dc systems, energy conversion & storage matchmaking event de... · efficient energy conversion...

DC Systems, Energy conversion & Storage

Matchmaking Event

30th April 2020

Efficient Energy Conversion Electromechanics and Electric Mobility

DC Grids and Storage for Smart Cities High Voltage DC Systems

High Voltage DC Diagnostics and Monitoring High Voltage DC Materials and Components

DC systems, Energy conversion & Storage

In the DCE&S MSc matchmaking event on April 30, you will meet the professors and PhD students of the DCE&S

section and hear about their areas of interest and research.

Event Location

The online event will take place on the Zoom Meeting App starting at 12.30 in general room ( Link to Enter

General Room).

After the general introduction at 12.40 you have to select one of the rooms according the research area. The

platform will have one meeting room (separate zoom address) per research area. Click on the link below to enter

the chosen room.

Topic Virtual Room (Zoom App) Moderator

Energy Efficient Conversion Link to Enter Blue Room Zian Qin

Electromechanics and Electric Mobility Link to Enter Purple Room Jianning Dong

DC Grids and Storage for Smart Cities Link to Enter Red Room

Laura Ramirez

Elizondo

HVDC Diagnostics and Monitoring

Link to Enter Green Room

Armando

Rodrigo Mor HVDC Materials and Components

Procedure

1) The MSc Students (you) must go through the Matchmaking booklet (will be shared soon) and select from the

proposed topics of interest.

2) The virtual rooms (Blue, Purple, Red and Green) will run parallel sessions so the interested students must make

a clear choice.

3) The project proposers will give a 3-minute pitch in a pre-decided sequence for the respective category's virtual

room. The sequence of the pitches is in the booklet.

4) During the pitch, the students may enter their specific questions on the room chatbox. Based on these

comments, the room moderator will ask the project proposer to make relevent clarifications immediately after

each pitch or after all pitches are done.

5) Each project proposer will take 5 minutes in total (3 minutes Pitch+ 2 minutes Clarification) . The schedule is

in the booklet.

4) After the pitches, the interested students can contact the project proposer via email or skype call. Contact

details of the project are in the Matchmaking booklet.

https://tudelft.zoom.us/j/97662677927







Hope to virtually see many of you on April 30. Invent the future with us!

If you have any questions about this event, you can email Aditya Shekhar ([email protected])

Schedule

Time Topic Speaker

12:30 pm General Room Welcome and Introductory Remarks Prof. Dr. Pavol Bauer

12:40 pm

Link to Enter Blue Room

Integrating Offshore Wind Energy In The Grid Lucia Beloqui

Larumbe

12:45 pm Low-Profile Pcb For An 11kw Wireless Charging

Converter Francesca Grazian

12:50 pm Wifi Communication For Ev Wireless Charging Francesca Grazian

12:55 pm Co2 Electrolysis: Modeling, Simulation And

Emulation Cristian Pașcalău

13:00 pm Impact Of Electrolyser Architecture On Fuel

Production Cristian Pașcalău

13:05 pm Learning With The Lab-Scale Modular Multilevel

Converter Aditya Shekhar

13:10 pm Develop A Novel Dynamic Voltage Dc Link

Operation Aditya Shekhar

13:15 pm E-Refinery: Efficient Sustainable Fuel Production Nils H. van der Blij

13:20 pm Investigation Of Pulse Charging On A Battery Pack

Level Wiljan Vermeer

13:25 pm Developing An Active/Reactive Power – Voltage

Control Technique For A 3-Phase Inverter Wiljan Vermeer

13:30 pm Study And Development Of Discontinuous Pwm

Methods For T-Type Three-Level Converter Yang Wu

13:35 pm Two-Interleaved Grid-Tied Converter For Dc Fast

Charging Station Yang Wu

12:40 pm

Link to Enter Purple Room

Smart Grid Technologies At Trolleygrid Substations Ibrahim Diab

12:45 pm Case Studies Of The Active Trolleygrid For More

Universal Recommendations Ibrahim Diab

12:50 pm Comparison Of Charging Infrastructures For

Electrified Buses Ibrahim Diab

12:55 pm Design Of Induction Heating System For Asphalt

Processing Jianning Dong

13:00 pm Multi-Objective Electrical Machine Optimization

Design Framework Based On Open Source Platforms

Jianning Dong

13:05 pm Online Parameter Identification Of Permanent

Magnet Synchronous Machines Jianning Dong

mailto:[email protected]







13:10 pm Virtual Machine – Power Hardware-In-Loop

Emulation Of Electrical Machines Jianning Dong

13:15 pm Wireless Powered Ultra-High Speed Vactrain Jianning Dong

13:20 pm Design A Resonant Dc-Dc Converter For Ev

Charging (Conductive) Dingsihao Lyu

13:25 pm Analysis Of The Imperfect Coupling Of Dynamic

Wireless Charging Systems Wenli Shi

13:30 pm Foreign Conductive Objects Detection For Dynamic

Wireless Charging Systems Wenli Shi

13:35 pm A Smart Charging Algorithm Development Considering Uncertainties In The System

Yunhe Yu

13:40 pm Hil Simulation Of Smart Charging Algorithm In

Distribution Grid Yunhe Yu

12:40 pm

Link to Enter Red Room

Charging Of Electric Vehicles Using Dc Trolley-Bus Grids

Aditya Shekhar

12:45 pm Optimization Of Battery Energy Storage System

Operation In Distribution Grids Marco Stecca

12:50 pm Power Electronics Control For Seamless Islanding

Transition Marco Stecca

12:55 pm Modelling, Stability, Control And Protection Of Dc

Grids Nils H. van der Blij

13:00 pm Experimental Design And Validation Of Dc Grids Nils H. van der Blij

13:05 pm Investigation Of Second Life Battery Degradation Wiljan Vermeer

12:40 pm

Link to Enter Green Room

Effect Of Staircase-Based Sinusoidal Waveform On Breakdown Strength Of Material Sample

Dhanashree Ganeshpure

12:45 pm Simulation Study Of Electric Field Distribution With

Staircasebased Sinusoidal Waveform Dhanashree Ganeshpure

12:50 pm Development Of A Pd Recognition System For Hvdc

Gis Based On Magnetic Antennas Fabio Muñoz

12:55 pm Design Of Cascaded H Bridge (Chb) Topology And

Its Size Estimation To Use As A Hv Test Source Dhanashree Ganeshpure

13:00 pm Feasibility Study About Generating Lightning Impulse Using Multilevl Converter Topologies

Dhanashree Ganeshpure

13:05 pm Design Of High Voltage Superconducting

Transformer Babak Gholizad

13:10 pm Replacement Strategy For Gas-Pressurized

Underground Cable Systems Babak Gholizad

13:15 pm Losses Model Of High Power High Frequency

Transformer Tianming Luo

13:20 pm Partial Discharge And Life Behavior Of Epoxy Under

High Dv/Dt Tianming Luo






13:25 pm High Temperature Superconductivity For

Degaussing Djurre Wikkerink,

13:30 pm Vote Based On Topics From Pages 39-46 In The

Matchmaking Booklet Mohamad Ghaffarian

Niasar 13:35 pm

13:40 pm

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D C E & S

DC Systems, Energy Conversion & Storage

Master’s Thesis Proposal

Efficient Energy Conversion DC systems, Energy conversion & Storage

INTEGRATING OFFSHORE WIND ENERGY IN THE GRID

Type of project: MSc thesis

Problem definition:

The converters in the wind turbines create some harmonic distortion that gets amplified through the network. Especially in the case of offshore wind farms, by the time this distortion reaches the PCC with the grid, it has been significantly amplified and there is a high risk of violating the grid code. Real wind farms have seen themselves forced to install very expensive – and inflexible – passive filters.

The scientific community has the challenge to try to devise new mitigation measures to reduce this amplification. However, this is not possible yet because nowadays we cannot even properly estimate the expected distortion at the PCC. Basically, nowadays the harmonic distortion at the PCC is estimated by using one technique called “Summation Law” but there is extensive proof in the literature (based on measurements on actual wind farms) that this summation law is not accurate.

The objective of this Master Thesis would be to check if another method (based on probability theory) delivers more accurate results than the Summation Law.

Methodology:

- Model a wind farm in the software PowerFactory. - Automate the simulation of the wind farm with different harmonic profiles injected by the

wind turbine converters based on a probabilistic profile. - Extract conclusions at the PCC. - Compare with Summation Law results.

This Thesis involves extensive simulations but no laboratory work. Possibility of writing a conference paper (depending on the student ambitions).

Skills the student will learn with this MSc Thesis:

• Application of statistics to a practical problem in Industry

• Using a very common software used in industry (PowerFactory)

• Knowledge on a topic that is – and will be for the years to come – fundamental for the development of renewable sources: integration in the grid.

Contact details:

• PhD: Lucia Beloqui Larumbe, [email protected] (SkypeID: luciablq)

• Supervisor: Dr. Zian Qin, [email protected]

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D C E & S




LOW-PROFILE PCB FOR AN 11KW WIRELESS CHARGING CONVERTER


Scope: Design a low-profile PCB for an 11kW wireless charging converter, such that it uses as heatsink the aluminum shield of the receiver coil.

Problem definition: An important constraint in wireless charging for electric vehicles is the physical. The receiver coil needs to be within the dimensions of the vehicle's chassis, and the power electronics onboard has also a limited space in which it can be placed. As a consequence, the power density is a challenge, especially because the automotive manufacturers are not willing to give up on much space. This problem can be mitigated by placing the power electronics in an at arrangement on the backside of the coil, such that the magnetic field shielding aluminum plate can also be used for heat-spreading.

Methodology: First, a literature research must be executed on the general characteristics of EVs wireless charging. After this, the focus is on power electronics used and their implementation. Since the final objective is to design a PCB with a high power density and high efficiency, a detailed thermal analysis needs to be carried out by simulations. In this way, the dimensions of the PCB can be found. As an example, important results are the thickness of both the thermal pad (X1) and aluminum shield (X2), and the minimum distance between the components (d). Finally, to verify these results, the designed PCB is going to be prototyped, and its heat-spreading capability is going to be tested.

Research Objectives:

• Understand and identify the challenges of a low-profile PCB for a wireless charging converter with high power density.

• Find out the minimum dimensions of the system, based on detailed thermal analysis.

Contact details:

• PhD student: Francesca Grazian ([email protected]). Skype: grazianfrancesca1

• Supervisor: Dr. Thiago Batista Soeiro ([email protected]) Prof. Pavol Bauer ([email protected])

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D C E & SDC Systems, Energy

Conversion & Storage



WIFI COMMUNICATION FOR EV WIRELESS CHARGING Type of project: Extra Project/ SIP 2

Scope:

To evaluate the feasibility of the Wi-Fi as a communication method for EV wireless charging in terms of communication speed, energy consumption, accuracy and interaction with multiple devices.

Problem definition:

The communication between transmitter and receiver in EVs wireless charging can allow different features such as supporting to the user in the coils’ alignment, the compatibility check of the systems, and requesting either the start, stop or pause of the charging process. Moreover, through the communication, the receiver can ask the transmitter for specific voltage levels while the charging process is running. In this project, the use of Wi-Fi (Sub-1 GHz) is evaluated for EVs wireless charging.

Methodology:

The (short) first phase is understanding the different wireless communication protocols (Bluetooth, Wi-Fi, ZigBee etc.). Then, the project is dedicated to familiarizing with TI Launchpad development Kits and programming them such that they can communicate through Wi-Fi (Sub-1 GHz). Therefore, the project is mainly taking place in the laboratory.


• Understanding the operation of TI Launchpad development Kits for Wi-Fi communication. • Characterize this communication in terms of speed, energy consumption, accuracy and space

range. • Evaluate the scenario in which multiple devices are interacting together. What would happen

to the charging process?

Contact details:

• PhD student: Francesca Grazian ([email protected]) Skype: grazianfrancesca1 • Supervisor: Dr. Thiago Batista Soeiro ([email protected])

Prof. Pavol Bauer ([email protected])

D C E & SDC Systems, Energy

Conversion & Storage



CO2 ELECTROLYSIS: MODELING, SIMULATION AND EMULATION Type of project: MSc thesis

Scope:

To develop an accurate electrical model and an emulator for H2O and CO2 electrolysis which enables the development of “power-to-fuel” technologies, accelerating the shift of the fossil-based liquid fuel industry towards renewable sources.

Problem definition:

Research into medium-to-large scale CO2 electrolysers is scarce and TU Delft’s e-refinery project aims at developing 100kW range prototypes in the next years. In order to develop the necessary power electronics converters for CO2 electrolysis, an accurate model which mimics the particularities of the process is needed. Due to the high cost and very low availability of CO2 electrolysers, the developed model will also serve as foundation for a hardware-in-the-loop emulator.

Methodology:

After initial literature review into electrolysis models and CO2 electrolysers in particular, electric models of electrolysis will be constructed, simulated and benchmarked for fitness to data available from the e-refinery institute. Last step is to assemble and validate a hardware-in-the-loop emulator.


• Understand the operation of a H2O and CO2 electrolyser • Construct electrical models of H2O and CO2 electrolysis • Benchmark the constructed model(s) against models from literature • Construct and test a HIL emulator

Contact details:

• PhD student: Cristian Pașcalău ( [email protected], Cristian Pascalau) • Supervisor: Dr. Thiago Batista Soeiro ([email protected])

Prof. Pavol Bauer ([email protected]) Nils H. van der Blij ([email protected])

Power supply Electronic load

Digital simulator

D C E & S




IMPACT OF ELECTROLYSER ARCHITECTURE ON FUEL PRODUCTION


Scope:

To create an optimization method for CO2 electrolysis stacks at different power levels and operating conditions.

Problem definition:

The impact of electrolyser architecture on the system efficiency is an under-researched topic and almost no research is available in the case of CO2 electrolysis. The main variables to consider when designing an electrolysis stack are: power supply limitations and efficiency, efficiency of the electrolysis process, nominal power of the stack and nominal power of individual cells and the usual operating power profile, cell variability, cost and availability. A systematic approach for is needed to obtain an optimum.

Methodology:

After initial literature review into both water and CO2 electrolyser stacks, various architectures will be simulated and benchmarked. The insights gained should allow for the development of an optimization algorithm. Most of the work will involve simulations and programming, as real hardware is not available.


Understand the operation of a H2O and CO2 electrolyser

Construction and evaluation of H2O and CO2 electrolysis stack models

Optimization algorithm

Contact details:

PhD student: Cristian Pașcalău ( [email protected], Cristian Pascalau)

Supervisor: Dr. Thiago Batista Soeiro ([email protected]) Prof. Pavol Bauer ([email protected]) Nils H. van der Blij ([email protected])

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D C E & S




Title: <Learning with the Lab-scale Modular Multilevel Converter>

Type of project: Extra Project

Scope: The available lab scaled modular multilevel converter (MMC) can be used to gain knowledge on real time digital simulator (OPAL-RT) and other hardware operation.

Problem definition: Experiment with the available lab-scaled MMC to understand the operation principles. Its operation will then be tested by applying different control strategies.

Methodology: Laboratory work is expected.


• Learn and test different PWM techniques and generate the required carrier wave to switch

the submodules.

• Apply simple control schemes, for instance capacitor balancing to test the proper operation

of the available lab-scale MMC.

Collaboration with Industry: <No>

Contact details:

• Postdoc: <A. Shekhar, [email protected]>

• Supervisor: < Prof. Dr. Pavol Bauer; Dr. Ir. Thiago Batista Soeiro>

1.

2

D C E & S




Title: Develop a Novel Dynamic Voltage DC Link Operation


Scope: It is possible to increase the dc link voltage without increasing the voltage ‘seen’ by the converter switches in a MMC. This improves the efficiency of the system without investing in higher rated components.

Problem definition: Develop a control strategy for operating the dc link with dynamic voltage while keeping the MMC energy within the rated limits to obtain efficiency and capacity improvement.

Methodology: The student is expected to prove this idea through simulations and implement it experimentally in the available lab scale converter. The fundamental equations1 will be given to the student for the implementation of this concept, for which familiarity with MATLAB is important.


• Show through simulations that the energy in the MMC can be controlled such that the dc link

voltage can be dynamically raised without increasing the voltage seen by the submodule

capacitors and switches.

• Define boundaries within which this concept can be applied.

• Determine the achievable efficiency/capacity gains of operating the MMC with dynamic dc

link voltage.

• Implement the concept in the available lab-scale MMC prototype to justify the claimed gains.

Contact details:

• Postdoc: <A. Shekhar, [email protected] >

• Supervisor: < Prof. Dr. Pavol Bauer; Dr. Ir. Thiago Batista Soeiro >

1 Refer conference paper: “Modular Multilevel Converter Performance with Dynamic MVDC Distribution Link Voltage Rating” in 18TH International Conference on Power Electronics and Motion Control At: Budapest, Bulgaria

<Photograph>

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D C E & S




E-REFINERY: EFFICIENT SUSTAINABLE FUEL PRODUCTION


Scope: To accelerate the energy transition towards sustainable energy via the integration of renewable energy resources, storage devices, and electrochemical conversion technologies Problem definition: Sustainable fuels can be produced from solar, wind, geothermal, ocean, biomass and hydro energy. Figure 1 shows that different electrochemical, thermochemical, biochemical or chemical processes are available to convert solar energy into sustainable fuels. Since the electrochemical route is expected to be one of the most efficient/cost effective it is the main subject of research for the e-Refinery project. However, more research is required to ensure the most efficient and cost effective conversion from these renewable sources to renewable fuels. Methodology: These topics mainly involve literature research and simulations, but design and experimental topics are also available. Examples of available topics are:

• Review of the different production routes for sustainable fuels

• Economic assessment of seasonal energy storage in hydrogen

• Optimization of the energy system aboard a hybrid ship

• Design of a novel power electronic converter for the production of sustainable fuels

• Ancillary services by storage systems

Contact details:

• Supervisor: Nils H. van der Blij ([email protected]) Prof. Dr. Eng. Pavol Bauer ([email protected])

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1

D C E & S




INVESTIGATION OF PULSE CHARGING ON A BATTERY PACK LEVEL


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Fig 1: Different cell balancing techniques: (a): passive balancing, (b): active balancing

Scope: Quantify the benefits of pulse charging on a pack level

Problem definition:

In literature the effects of pulse charging on a single cell have been studied. If operated under the right conditions (duty cycle and frequency), it has shown to have various benefits for batteries such as improved efficiency, reduced charging time and increased lifetime. However, on a module/pack level components such as the BMS (cell balancing) and protection circuitry affect the possible benefits of pulse charging. Furthermore, these effects have not been investigated yet in literature. Therefore, the goal of this thesis is to quantify to effects of pulse charging on a module/pack level. To do this, the effect of pulse charging of all relative components inside the pack will be analysed.

Methodology:

• Perform a literature study on pulse charging and battery packs

• Simulate the effect of pulsed charging on all relative components

• Perform lab tests to verify the results


• Literature review

• Develop simulations of batteries cells and BMS circuitry.

• Develop a testing setup

Contact details:

• PhD students: Wiljan Vermeer, [email protected]

• Supervisors: Dr. Ir. Gautham Ram Chandra Mouli [email protected]

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D C E & S




DEVELOPING AN ACTIVE/REACTIVE POWER – VOLTAGE CONTROL TECHNIQUE FOR A 3-PHASE INVERTER

Type of project: Extra project / MSc thesis

Fig 1: (a) Voltage droop control (b) 3-phase inverter

Scope: Develop a reactive power control loop for voltage droop control

Problem definition: Increasing rate of renewables can cause local voltage instability. Depending on the impedance of the grid active and/or reactive power support can help in preventing under/over-voltages. The goal of this extra project is to develop an active/reactive power control loop, which can perform voltage droop control.

Methodology: The methodology used in this thesis:

• Investigate current and future solar inverter grid codes/requirements

• Simulate the proposed control

• Implement the proposed control on an existing 3-phase inverter

Research Objectives: The pertinent research objectives are highlighted below:

• Perform a literature review of all relevant aspects.

• Show operation in simulation.

• Implement on hardware.

Contact details:

• PhD students: o Wiljan Vermeer, [email protected]

• Supervisor: o Gautham Ram Chandra Mouli [email protected]

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D C E & S




STUDY AND DEVELOPMENT OF DISCONTINUOUS PWM METHODS FOR T-TYPE THREE-LEVEL CONVERTER

Type of project: Extra Project / SIP2

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Scope:

Study the three-phase T-type three-level converter and develop related discontinuous PWM strategy.

Problem definition:

T-type 3L-NPC circuit is an alternative solution for the diode-clamped 3L-NPC inverter. This can be advantageous for moderated switching frequencies. Additionally, it displays the beneficial features of three-level voltage source converters such as lower harmonics and consequent smaller filter size, it can attain good power efficiency, and higher power density. When compared to the conventional 3L-NPC, the main advantages of the T-type structure are: 1) it requires two fewer power diodes;2) it can provide lower conduction losses (but higher switching losses). The implementation of the discontinuous PWM methods in T-type 3L-NPC circuit can reduce the switching losses, however, this is only effective at limited power factor range.

Methodology:

To study different discontinuous PWM methods for T-type three-level converter. Propose a interesting discontinuous PWM strategy to minimise the switching losses. Simulate the proposed method in Simulink/PLECS. The proposed modulation strategy will be finally tested in the laboratory prototype.


• Literature review in operation and PMW methods for T-type three-level converter

• Propose an optimized discontinuous PWM strategy and simulate it in Simulink/PLECS

• Test the proposed method in the prototype

Contact details:

• PhD student: Yang Wu: <[email protected]> (Email & Skype ID)

• Supervisor: Prof. Dr. Pavol Bauer; Dr. Ir. Thiago Batista Soeiro

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D C E & S




TWO-INTERLEAVED GRID-TIED CONVERTER FOR DC FAST CHARGING STATION


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Scope:

Design a 50 kW two-interleaved grid-connected converter system based on three phase 2-level VSC.

Problem definition:

The conventional three phase 2-level VSC has higher efficiency with low switching frequency at medium power (e.g, 100 kW), compared with other topologies such as 3-level NPC or T-type. However, the two-level output characteristic requires a bulky LCL filter to improve the THD performance of the output current, which sacrifice system power density. Interleaved converter system with two 2-level VSCs offers improved output harmonics spectrum with specific PWM strategies, which implies a reduced filter size and improved power density. The inherent problem of circulating current in the parallel-interleaved system occurs, however this can be supressed by installing intercell (highly-coupled) transformers (ICT), , but at the cost of increased total filter size. A clear trade-off lies in the design of the system with high power density.

Methodology:

To study the operation, modelling and control of 2-level VSC. Investigate the state-of -the-art PWM strategies for harmonics cancellation, and active solutions for suppressing the circulating current. Design the LCL filter system with optimized Intercell transformer.


• Literature review in modelling, PWM strategies and control of 2-level VSC and interleaved two-level converter.

• Design the LCL filter with ICT to optimize the system power density

• Simulate in Simulink/PLECS and test the prototype

Contact details:

• PhD student: Yang Wu: <[email protected]> (Email & Skype ID)


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D C E & S



Electromechanics and Electric Mobility DC systems, Energy conversion & Storage

SMART GRID TECHNOLOGIES AT TROLLEYGRID SUBSTATIONS

Type of project: <MSc thesis>

Scope:

Trolleybuses are powered by connecting to the overhead wires, in the same way a tram operates. The trolleygrid network is typically divided into sections, fed from substations. These substations are typically unidirectional, and are galvanically isolated from other sections fed by other substations. Some grids have bilateral connections, which is a controlled isolation between the sections, which allows for power sharing when the line voltage is, for example, too low or too high.

Problem definition:

Bidirectional substations and bilateral connections will alter the power flow in the trolleygrid as we know it. As other technologies get introduced into the trolleygrid (e.g., PV systems, storage, EV charging, etc.) it is interesting to investigate the constructive or destructive effect of implementing more than one solution together.


Estimate the energy and power consumption of a fleet of electric buses in the presence of bidirectional substations or bilateral connections. Also, investigate the effect of adding more than one smart grid technology into the system.

Methodology:

• Estimate the energy and power consumption of busses in a conventional grid

• Study the effect of bilateral connections on a grid with in-motion-charging busses

• Study the effect of bidirectional substations on a grid with PV systems

• Study the effect of bidirectional and bilateral on a grid with PV and IMC busses

• Motivated students can go further by looking into EV charging and/or Storage

Contact details:

• PhD student: <Ibrahim Diab, [email protected] >

• Supervisor: <Dr. Gautham Ram Chandra Mouli; Prof. P Bauer>

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D C E & S




CASE STUDIES OF THE ACTIVE TROLLEYGRID FOR MORE UNIVERSAL RECOMMENDATIONS


Scope:

A trolleybus is an electric bus that draws power from overhead wires, in the way a tram does. Today’s DC trolley grids only serve the purpose of powering these buses, although they have the potential to be a more active grid with integrated storage and distributed generation.

Problem definition:

Trolley grids are DC grids with indirect CO2 emissions (depending on the electricity source). Stationary storage is already implemented in some grids to recuperate the braking energy of the buses and help the voltage profile as well as reducing the energy demand, and thereby the CO2 footprint. PV is a good way to reduce this footprint, especially that both PV and the grid are DC, and that the storage is already available. The trolleygrid energy consumption, is a function of the local factors: how hilly the city is, traffic situation, heating/cooling requirements, type of busses used, etc. Evidently, recommendations for one city cannot be directly translated for another city.


Investigate the pros and cons of adding PV and storage (or other technologies) into the grid for a few cities (e.g., Arnhem, Szeged, Gdynia, Solingen, etc.). Then, compare the cities and draw recommendations, based on their local profiles, for other cities with the same (or combined) profile (for example the traffic of Gdynia but the topology of Solingen)

Methodology:

• Estimate the energy and power consumption of busses in a conventional grid

• Study the effect of PV and storage on the grid power and energy demand.

• Repeat the study for a few cities (data is available for some European cities) and conclude on the effect of different city parameters on the viability of PV and storage

• Motivated students can also look into the difference between cities for other smart grid technologies such as EV charging or bilateral connections

Contact details:



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D C E & S




COMPARISON OF CHARGING INFRASTRUCTURES FOR ELECTRIFIED BUSES


Scope:

A main objective of current Electric Mobility research is to achieve reliable transportation while minimizing both the catenary-dependent operation and the costs. Buses can receive the needed electrical energy in a variety of ways. One method is from overhead trolley lines or In-Motion-Charging. Another possibility is “opportunity charging” of the on-board batteries at the bus stops or at the end-of-the-line. Finally, there is the “overnight charging” at the dedicated depots.

Problem definition:

Trolley buses and IMC require relatively smaller battery designs, but with a need for overhead lines. Opportunity charging takes away from the route and timetable flexibility and can incur serious schedule delays. Overnight charging methods work only with significantly large storage.


Estimate the energy consumption of a fleet of electric buses in presence of different charging infrastructures, locations, and bus types and determine the proper capacity of the five proposed infrastructures. Then, quantifying operational and installation costs and its trade-offs with the driving range extension.

Methodology:

• Compare the technical implications of different methods such as overnight charging, opportunity charging, in-motion charging and trolley systems.

• Model the driving range of an electric bus based on the specification, velocity profile, on-board storage and charging infrastructure.

• Minimize the storage requirement using different charging solutions while maximizing the driving range of the bus.

• Determine the economic viability of the chosen charging scheme for a case-study with a fleet of electric buses in a city route (for example: Arnhem, Gdynia, or Szeged)

Contact details:



D C E & S




DESIGN OF INDUCTION HEATING SYSTEM FOR ASPHALT PROCESSING


Scope: This project aims at preliminary study on the design of an induction heating system for asphalt processing.

Problem definition: Drying of asphalt requires huge amount of heat. The state of the art technology is to heat up the asphalt by burning natural gas, which is one of the biggest CO2 source. The electrification of the drying process using renewable energy is needed to reduce the CO2 footprint of the asphalt industry. Induction heating is one of the promising solutions to the asphalt process electrification. A rotating drum and corresponding coils should be designed based on the heating power and discharge rate requirements. Power electronics converters and corresponding compensation network should be designed to keep the induction heating drum working close to the resonant operation point.

Methodology: The working profile of the induction heating system is first identified from the system requirements. Power and energy required of the system will be calculated based on analytical models. Induction coils and the rotating drum will be designed based on both analytical equations and finite element analysis (FEA). Cooling of the coils will be designed and evaluated based on thermal circuit or FEA. Power electronics components and compensation circuits will be chosen based on circuit simulation.


• Preliminary mechanical, electromagnetics and cooling design of the induction heating

system.

• Preliminary design of the power electronics converters for the induction heating system.

Contact details:

• Daily Supervisor: Dr. Jianning Dong ([email protected])

Dr. Thiago Batista Soeiro ([email protected])

• Supervisor: Prof. Pavol Bauer ([email protected])

D C E & S




MULTI-OBJECTIVE ELECTRICAL MACHINE OPTIMIZATION DESIGN FRAMEWORK BASED ON OPEN SOURCE PLATFORMS


Photo courtesy: pyleecan project (http://www.pyleecan.org/)

Scope: This project aims at developing an electrical machine design and optimization framework based on open source platforms.

Problem definition: Emerging applications including transportation electrification, robotics and renewable electricity generation require customized design of electrical machines, so that the designed machines meet multi-physical constraints and have the most optimal performance. Therefore the design process should be a multi-physical approach and requires effective optimization methods. There are numerous open source packages available to model different aspects of electrical machines and optimize the design. However, in order to use them for the electrical machine design, they should be synthesized to work effectively.

Methodology: Electrical machine design methodology and criteria should be studied first. Then suited open source software packages will be reviewed and chosen based on the design methods and criteria. Interface codes will be developed and tested. Developed codes will be made open source to the community after the project finishes.


• Review of available open source packages can be used for electrical machine design.

• Development of interfaces and glue code to deliver a complete electrical machine design

framework.

• Use the developed framework to optimize electrical machines for transportation

electrification applications.

Contact details:



D C E & S




ONLINE PARAMETER IDENTIFICATION OF PERMANENT MAGNET SYNCHRONOUS MACHINES


Scope: Identify the inductance, flux linkage and resistance of permanent magnet synchronous machines for faster and more accurate control.

Problem definition: Permanent magnet synchronous machines are used extensively in renewable energy, transportation and industry process. The performance of the permanent magnet machine based drive system is highly dependent on how accurate the machine parameters are, because not only maximum torque per ampere (MPTA) control , flux weakening control, but also the position sensor-less control are dependent on those parameters. However, these parameters are heavily dependent on the temperature and saturation of the machine. In order to achieve highly dynamic performance, online parameter identifications should be implemented.

Methodology: The research will start with a literature study on all available online parameters identifications. The most suitable method for the machine in the lab will be proposed based on the investigation. Then simulation models will be used to develop and compare the identification methods. In the end, the simulated methods should be implemented in hardware and tested in the lab setup.


• A review of all available parameter identification methods.

• Implementation and comparison of different methods in simulation.

• Development and deployment the parameter identification methods in hardware.

Collaboration with Industry: No

Contact details:


Dr. Thiago Batista Soeiro ([email protected])


D C E & S




VIRTUAL MACHINE – POWER HARDWARE-IN-LOOP EMULATION OF ELECTRICAL MACHINES


Scope: This project aims at development of a power hardware-in-loop (HIL) emulation system of electrical machines.

Problem definition: Power-HIL simulations are essential for cost-effect and time-effective developments of modern powertrains in electric vehicles and electric aircrafts. Control algorithms can be tested through mathematical dynamic models of electrical machines without building real prototypes. To fully represent the dynamic performance of the electrical machine, magnetic saturation, losses and temperature rise of motors should be considered in the model. Comprehensive models should be built and integrated in the real time simulation platform. A power converter will be used to mimic the dynamic behaviour of the emulated electrical machine. High bandwidth current controller and filters should be designed to ensure fast and precise response of phase currents.

Methodology: HIL simulation platform has been developed in MATLAB/Simulink and OPAL-RT. Filtering and sensing circuits, and current controllers should be designed to achieve fast and accurate response so that the currents of the virtual machine follows the predicted values from the HIL models.


• Design and implementation of filtering and sensing circuits

• Design and implementation of a high bandwidth, high precision current control loop

• Power HIL emulation of a permanent magnet synchronous machine

Contact details:



D C E & S




WIRELESS POWERED ULTRA-HIGH SPEED VACTRAIN


ACDC

StationStation Station

3ph Charging rail Cruising rail

Battery Train

Scope: This project aims at feasibility study and preliminary design of a wireless powered ultra-high speed train using evacuated tubes (vactrain).

Problem definition: Research on vactrain has been focused on propulsion or magnetic levitation of the train. The power supply of the train, although is equally or even more important from the system point of view, is often neglected. At such high speeds, it is not possible to use the conventional pantograph-based system to power the train because of friction and arcing. This project proposes to apply dynamic wireless charging technology in vactrains, and integrate the wireless power transfer system with the propulsion system, based on the principle of doubly fed induction machine. The charging rail is laid close to and at the stations, which is equipped with coils. When the train stops at, approaches or leaves the stations, the train side coils and the charging rail from a doubly fed induction machine, which is used for both propulsion/braking and battery charging. During cruising, the train side coils can form an induction machine or a reluctance machine together with low-cost passive rails to provide minimal power required for cruising and after failure restart.

Methodology: A mission profile of the vactrain is first defined. Power and energy required of the system will be calculated based on analytical models. Size and weight of key components will be calculated based on both analytical results and simulations. Finite element method may be needed to validate the design.


• Feasibility study of wireless powered vactrain, with integrated propulsion system.

• Preliminary design of the wireless charging system.

• Analytical design and numerical validation of the integrated propulsion charging system.

Contact details:



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D C E & S




DESIGN A RESONANT DC-DC CONVERTER FOR EV CHARGING (CONDUCTIVE)


Scope:

Design a 10kW resonant DC-DC converter for EV charging applications, aiming for the best trade-off among price, efficiency and power density.

Problem definition:

Resonant DC-DC converter is one of the most popular DC-DC converters in data center and consumer electronics. While having advantages such as high peak efficiency and low EMI, etc., the resonant converters also have drawbacks such as limited operation range. In EV charging applications where the range of the output voltage and power is wide, how would the resonant converter perform compared to other topologies, in terms of price, overall efficiency and power density? What if a non-isolated DC-DC converter, such as a buck-boost converter, is added to the primary or secondary side of the transformer to improve the performance of the system in wide voltage ranges?

In this project, a multi-objective (price, efficiency, and power density) design of a resonant converter (with or without a non-isolated DC-DC converter) is to be conducted. The design will be benchmarked with a phase-shift full-bridge and a dual-active bridge DC-DC converter.

Methodology:

• Literature review of resonant DC-DC converters in EV charging application.

• Choose 2~3 most suitable topologies for further investigation.

• Build analytical models (MATLAB, MATHCAD…) for the topologies chosen, verify the models using simulation tool (PLECS, LTspice, SIMULINK…).

• Design a 10kW resonant DC-DC converter with the optimal trade-off among cost, efficiency, and power density, using the analytical and simulation models built.



• Analytical and simulation models for resonant converters

• Multi-objective design of resonant converter for EV charging application

Contact details:

• PhD student: Dingsihao Lyu ([email protected], same for skype ID)


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ANALYSIS OF THE IMPERFECT COUPLING OF DYNAMIC WIRELESS CHARGING SYSTEMS


DCAC

DCAC

DC Power

Road

Receiver

Transmitter Transmitter

Road

Transmitter

Scope: As an approach to mitigate the range anxiety and bulky battery packages of EVs, dynamic inductive power transfer (DIPT) for EVs charging attracts lots of attention. Compared with stationary charging, DIPT systems are faced with more critical operation conditions because of the displacement between the transmitter and the receiver.

Problem definition: In DIPT systems, transmitters are discretely deployed in a string along the lane. If transmitters are placed too close, cross coupling of transmits can be introduced to the system and leads to extra reactive power. Besides, one receiver can be coupled with multiple transmitters, which complicates the design of DIPT system.

Methodology:

• Study of the basic principles of inductive power transfer technology

• Modeling and analysis of the primary cross coupling

• Modeling and analysis of the one-receiver-multiple-transmitters coupling


• Modeling approach of the imperfact coupling of DIPT systems

• Guidelines to mitigate the adverse effect of the imperfect coupling

Contact details:

• PhD student: Wenli Shi [email protected], LB 03.850

• Supervisor: Dr. Jianning Dong [email protected], LB 03.630 Prof. Pavol Bauer [email protected] , LB 03.600

1

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FOREIGN CONDUCTIVE OBJECTS DETECTION FOR DYNAMIC WIRELESS CHARGING SYSTEMS


Scope: As an approach to mitigate the range anxiety and bulky battery packages of EVs, dynamic inductive power transfer (DIPT) for EVs charging attracts lots of attention. Conductive objects like coins and cans may exist on the road, and performances of dynamic IPT system can be affected if these objects are placed on top of transmitters under roads.

Problem definition: When conductive objects are placed near or in the magnetic field produced by DIPT systems, eddy current will be generated. This eddy current could lead to power loss, change in magnetic field and electrical waveforms. Foreign object detection methods should be proposed to solve this problem.

Methodology:

• Study of the basic principles of inductive power transfer technology

• Literature review of the foreign conductive objects analysis detection methods

• Simulation of the influence of foreign objects on DIPT systems

• Analysis of a kind a foreign object detection method


• Modeling method of the foreign conductive objects effect on DIPT systems

• Design methodology of a kind of foreign object detection method

Contact details:

• PhD student: Wenli Shi [email protected], LB 03.850

• Supervisor: Dr. Jianning Dong [email protected], LB 03.630 Prof. Pavol Bauer [email protected] , LB 03.600

1

D C E & S




A SMART CHARGING ALGORITHM DEVELOPMENT CONSIDERING UNCERTAINTIES IN THE SYSTEM


source: Elaad

Scope:

Smart charging is a series of intelligent functionalities to control the EV charging power in order to create a flexible, sustainable, low cost, and efficient charging environment. This project aims at developing a smart charging algorithm that considering the uncertainty of the system, including the base load variation, the PV generation fluctuation and the EV user behaviour changes.

Problem definition:

When we develop a smart charging algorithm, there are many uncertainties in the system that need to be taken into consideration. For example, the EV arrival/departure time, the EV requested charging energy, the PV generation, the grid baseload variation, etc. Apart from the regular system fluctuation, there are also unpredicted interruptions happen from time to time, for instance a PV system failure, a sudden extreme high power demand from the local load. These uncertainties strongly influence the system parameters which impact the results, or even lead to infeasible results if we only have a deterministic algorithm.

Therefore, it is vital to include the uncertainties in the system to ensure a stable and accurate performance of the smart charging algorithm.

Methodology:

The student is expected to study the state of the art of the smart charging algorithms including the system uncertainties and to find the challenges. Then the work will focus on developing the algorithm which takes the aforementioned problems into consideration. Finally, the student is expected to do the simulations to compare the developed algorithm with the uncontrolled EV charging. The platform will be applied are ( but not limited to): Matlab, Simulink, Python, PowerFactory.


• Literature study of the state of the art of the smart charging algorithm considering system uncertainties

• Develop the smart charging algorithm

• Operate the simulations to compare the developed algorithm with the uncontrolled EV charging

Contact details:

• PhD student: Yunhe Yu, [email protected]

• Supervisor: Prof. Dr. ir. Pavol Bauer, [email protected] Dr. Gautham Ram [email protected]

1

D C E & S




HIL SIMULATION OF SMART CHARGING ALGORITHM IN DISTRIBUTION GRID


Scope:

This project aims at first model a real distribution grid and a smart charging algorithm in a hardware-in-loop (HIL) simulation system, then run the simulation to compare the system performance with and without the smart charging algorithm.

Problem definition:

A developed smart charging algorithm may behave differently in real applications because lots of practical factors were simplified or not considered. It is then very important to verify the algorithm in a real environment. However, it is not always feasible to test the algorithm in a real distribution grid.

HIL is a cost-effective and time-efficient method to implement large-scale grid experiments. In this system, a power amplifier, an AC or DC charger and a EV emulator will be connected to the simulator to model the real charging environment. OPAL-RT will be employed as the HIL simulator. With this system, a close to the real-life environment can be established and the algorithm can be tested with less time and low cost yet still have promising outcomes.

Methodology:

The student should first do a literature study on the topic of HIL simulation and EV smart charging algorithm. After the literature study, the student is expected to rebuild the given grid model in the HIL system and implement the given smart charging algorithm in the system. Then operate the EV charging simulations with/without smart charging algorithm and compare the results.


• Build the given grid model in the HIL system

• Implement the given smart charging algorithm in the HIL system

• Real-time simulation and compare the controlled/controlled EV charging in the distribution grid

Contact details:

• PhD student: Yunhe Yu, [email protected]

• Post Doc: Aditya Shekhar, [email protected]

• Supervisor: Prof. Dr. ir. Pavol Bauer, [email protected] Dr. Gautham Ram [email protected]

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DC Grids and Storage for Smart Cities DC systems, Energy conversion & Storage

Title: Charging of Electric Vehicles using DC Trolley-Bus Grids


Scope: DC traction networks that supply power to trolley-buses, tramcars and trains can be simultaneously used to integrate fast-charging stations for Electric Vehicles (EVs). This strategy improves the traction grid utilization of urban transportation systems. In addition, it offers a potential solution to the increasing requirement of charging infrastructure due to proliferation of plug-in EVs and the associated impact on the existing distribution network.

Problem definition: Determine the best integration strategy for EV charging using the dc trolleygrid infrastructure.

Methodology: Modelling different trolley grid structures and EV integration strategies to simulate the impact in terms of energy efficiency and capacity footprint.


• Explore different converter topologies that can be used to integrate EV charging

infrastructure to the existing dc trolley-grid network.

• Evaluate the impact of chosen integration methods on the network infrastructure to suggest

preferred solution.

• Recommend the EV integration strategy for different overhead network sections using a

case-study based on the data available for Arnhem city Trolley-bus grid.

• We can discuss to add some lab related study if an interested student so requests.

Contact details:

• Post-doc: <A. Shekhar, [email protected] >

• Supervisor: <Gautham Ram Chandra Mouli, [email protected]>

<Photograph>

1

D C E & S




OPTIMIZATION OF BATTERY ENERGY STORAGE SYSTEM OPERATION IN DISTRIBUTION GRIDS


Scope:

Optimization of BESS schedule considering technical and commercial services to enhance distribution grid performances and BESS revenues.

Problem definition:

Battery Energy Storage Systems (BESS) are a promising asset in future distribution grids. They can be deployed for a several purposes, from enhancing the grid capacity in hosting renewable generators, to stabilize the grid frequency. Despite their flexibility of operation, one of the main drawback of such systems is the high initial investment they require, and the uncertain revenue stream.

This master thesis aims at addressing this issue. Optimizing the BESS operation can lead to higher revenues and better utilization of the system’s capabilities.

Methodology:

The research consists on first studying the functionalities of BESS in distribution systems, both in terms of technical requirements and of remuneration. Secondly the student will define the optimization problem and apply it on a case study.


Identify the set of functionalities to be performed by the BESS.

Define and set the optimization problem.

Verify the technical and economical feasibility of the solution obtained in a case study.

Contact details:

PhD student: Marco Stecca <[email protected]> Skype ID: mstecca94

Supervisors: Dr. Ir. Laura Ramirez Elizondo <[email protected]> Prof. Dr. Ir. Pavol Bauer <[email protected]>

1

D C E & S




POWER ELECTRONICS CONTROL FOR SEAMLESS ISLANDING TRANSITION


Scope:

Develop and test control strategies for power electronic converters to allow a seamless transition of distribution grids during unintentional islanding.

Problem definition:

Islanding operation is a situation in which a portion of electric grids continues to operate even if disconnected from the main network. Islanding can be intentional or unintentional, the second condition it is not yet allowed due to difficulties of grid operators in ensuring an acceptable level of security and power quality to the customers.

However with an increasing penetration of distribution generators (DG) and storage systems (ESS) it might be possible to operate distribution grids in islanding operation safely. The main challenges are first in detecting the fault, then in controlling the transient that arises accordingly and, if these two steps are completed successfully, in keeping the system stable balancing loads and generation.

Methodology:

The research consists on first studying the islanding operation of distribution grids, the load/generation requirements and the role of storage in this. Second the student will develop a control strategy for the power electronic converters in order to manage the transient during the island formation.


Study the grid requirements for sustaining islanding operation.

Evaluate the role of the power electronics device in the dynamic behaviour of the grid during the transition.

Design a control strategy for achieving a seamless transition after the disconnection from the main grid.

Contact details:

PhD student: Marco Stecca <[email protected]> Skype ID: mstecca94

Supervisors: Dr. Ir. Thiago Batista Soeiro <[email protected]> Dr. Ir. Laura Ramirez Elizondo <[email protected]> Prof. Dr. Ir. Pavol Bauer <[email protected]>

1

D C E & S




MODELLING, STABILITY, CONTROL AND PROTECTION OF DC GRIDS


Fuse

~

Macrogrid Zone 1

Zone 0

Zone 3

Zone 2

Zone 3

Circuit Breaker

Scope: To aid the broad adoption of DC distribution grids more research is required on the modelling, stability, control and protection of dc distribution grids. Many topics within these categories are available for master students. Problem definition: Distribution grids are subjected to changes such as the increasing participation of distributed energy resources (DER), segmentation of the grid (for example into microgrids), and increasing participation of prosumers. This poses significant challenges with respect to stability, control and protection. DC distribution grids are foreseen to have several advantages over ac in terms of efficiency, distribution lines, and converters. Furthermore, they do not require the synchronization or reactive power governance. Therefore, the interconnection of dc (micro)grids is significantly simpler. Methodology: These topics mainly involve literature research, analytical derivations, simulations and/or programming. However, design/experimental topics are also available. Examples of available topics are:

• Power flow control in DC distribution grids

• Transient analysis of DC distribution grids

• Small-signal stability of DC distribution grids

• Centralized/decentralized/distributed control of DC distribution grids

• Optimal sizing and allocation of storage in DC distribution grids

• Protection of DC distribution grids

Contact details:


1

D C E & S




EXPERIMENTAL DESIGN AND VALIDATION OF DC GRIDS


Scope: It is essential for the broad adoption of DC grids to design an experimental set-up and verify the research done on the modelling, stability, control and protection of these grids. Different projects are available to design converters, protection devices or perform experiments. Problem definition: DC grids are foreseen to have several advantages over ac in terms of efficiency, distribution lines, and converters. However, more theoretical and experimental work is required to aid the broad adaptation and exploit these advantages. A dc microgrid set-up is available in the lab to do the verification and validation of dc distribution system research. However, new or improved components for this microgrid need to be designed and built for future research. Methodology: These topics either mainly involve the design of converters, solid-state protection devices and/or the execution of experiments. Moreover these projects might entail literature research, simulations and microcontroller programming. Examples of Research Objectives:

• Design of an isolated DC/DC converter

• Design of a solid-state circuit breaker

• Design and implementation of the communication between power electronic converters

• Conduct experiments regarding the control of DC distribution grids

• Conduct experiments with respect to the protection of DC distribution grids

Contact details:


1

D C E & S




INVESTIGATION OF SECOND LIFE BATTERY DEGRADATION


(a) (b)

Fig 1: (a): EV battery life cycle incl. second life. (b): Tesla Model S milage vs. remaining battery capacity

Scope: Investigate critical degradation factors and develop a second life degradation model

Problem definition: In the future, second life EV batteries are expected to play a large role in stationary applications such as building energy storage or grid support applications. From Fig. (1)-b it is clear that EV batteries still have a 70-80% remaining capacity at the end of their first life. The goal of this thesis is to investigate critical degradation factors for second life batteries and develop a second life degradation model based on cycle and calendar life aging tests.

Methodology:

• Perform a literature study on (second life) battery degradation.

• Perform calendar and cycle life tests.

• Develop an empirical second life degradation model.



• Quantification of most significant aging factors

• Develop a testing setup

• Develop an empirical model

Contact details:

• PhD students: Wiljan Vermeer, [email protected]

• Supervisors: Dr. Ir. Gautham Ram Chandra Mouli [email protected]

1

D C E & S



High Voltage DC Diagnostics and Monitoring DC systems, Energy conversion & Storage

[1] ] J. Wu, “Effects of Transients on High Voltage Cable Insulation”, Delft University of Technology, 2020

TITLE: EFFECT OF STAIRCASE-BASED SINUSOIDAL WAVEFORM ON BREAKDOWN STRENGTH OF MATERIAL SAMPLE


(a) (b) (c) Figure: (a) Staircase waveform (b) Schematic of setup (c) Sample test cell [1]

Scope: The goal is to study the effect of the staircase-based sinusoidal waveform on the breakdown strength of different material samples.

Problem definition: TU Delft and KEMA laboratories are collaborating to create a universal High Voltage (HV) test source capable of generating arbitrary waveforms using multilevel converter topologies. Such a Power Electronics (PE) based HV test source generates HV test waveforms in the form of a staircase waveform when the nearest level control methodology is used. The goal of the project is to compare the breakdown strength of different material samples when subjected to a staircase waveform-based sinusoidal and a pure 50 Hz sinusoidal waveform. The mentioned waveforms are shown in figure (a).

Methodology: Since the PE-based test source is not ready in our lab, arbitrary waveform generator and HV amplifier are used to generate the staircase waveforms with the different number of levels. Material samples of XLPE and epoxy resin will be prepared with a small thickness. First, the dielectric strength of prepared samples will be calculated statistically for pure sinusoidal waveform. Later, various staircase-based waveforms will be applied and dielectric strength will be calculated and compared with pure sinusoidal one.


• Literature review about the testing methodology for breakdown strength measurement

• Preparation of different sample materials

• Preparation of test setup

• Perform different tests with pure sinusoidal and staircase-based waveform

• Analyse the obtained results statistically

Contact details:

• PhD student: <Dhanashree Ganeshpure, [email protected] >

• Supervisors: <Mohamad Ghaffarian Niasar, [email protected]> <Thiago Batista Soeiro, [email protected]>

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High Voltage DC Diagnostics and Monitoring


TITLE: SIMULATION STUDY OF ELECTRIC FIELD DISTRIBUTION WITH STAIRCASE-BASED SINUSOIDAL WAVEFORM

Type of project: <Extra project>

(a) (b) (c) Figure: (a) Staircase waveform (b) Air Corona (c) Coil

Scope: The goal is to study the effect of the staircase-based sinusoidal waveform on the electric field distribution for an air corona setup and a coil.

Problem definition: TU Delft and KEMA laboratories are collaborating to create a universal High Voltage (HV) test source capable of generating arbitrary waveforms using multilevel converter topologies. Such a Power Electronics (PE) based HV test source generates HV test waveforms in the form of a staircase waveform when the nearest level control methodology is used. The goal of the project is to compare the electric field distribution with a staircase waveform-based sinusoidal and a pure 50 Hz sinusoidal waveform to an air corona setup and a coil. The mentioned waveforms are shown in figure (a).

Methodology: The project will start with a brief literature review about the electric field distribution of an air corona setup and a coil when subject to a pure sinusoidal waveform. The next step will be to estimate the electric field distribution in those setups with a staircase-based sinusoidal waveform. The theoretical estimation will be verified with simulations from COMSOL multiphysics software.


• Literature review about electric field distribution about air corona setup and coil with a pure sinusoidal waveform

• Estimation of electric field distribution with a staircase-based sinusoidal waveform

• Time dependant simulation in COMSOL multiphysics software

Contact details:



1

D C E & S





TITLE: AC LOSS MODELLING IN SUPERCONDUCTING TAPES AND CABLE

Type of project: < Extra Project>

Scope:

< The scope of this project is to develop a finite element model for calculating AC losses in the superconducting

tape with different tape size and cable design.>

Problem definition:

< Superconductors are materials that can conduct a stationary electrical current without resistance. Alternating

magnetic fields and transport currents cause dissipation of energy in superconductors. The energy dissipation is called AC loss. The magnetic field penetrates the material in the form of flux lines. The magnetic-field variation inside the material induces an electric field E according to Faraday’s law. The electric field drives “screening currents” in the material. The screening currents determine the magnetic-field distribution in the superconductor according to Ampere’s law. The screening currents dissipate energy given by E.J. The energy is delivered by the external magnetic field and is supplied by the power source which generates the magnetic field. The energy is required for depinning and moving the flux lines, which is a dissipative process. The energy is converted into heat that must be removed by the high cost and low efficiency cooling system. AC loss is therefore an undesirable phenomenon.>

Methodology:

< The research is included the modelling of the cable in COMSOL Multiphysics® software and calculating the AC

loss (the energy which is required for depinning and moving the flux lines). >


• <literature review, getting use to the existing model (how is it made, boundary conditions, functionality and limitations) Model the superconducting cable in COMSOL Multiphysics® software. >

• < Calculating the AC loss and validating with the available publications>

• < Reducing the AC loss by changing the configuration of the superconducting tapes. >

Contact details:

• Supervisor: < Mohamad Ghaffarian Niasar, [email protected]

Babak Gholizad, [email protected], Rob Ross, [email protected]

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D C E & S





TITLE: AGING MECHANISM OF CABLE INSULATION AT HIGH FREQUENCY HARMONICS

Type of project: < MSc thesis>

Scope:

< The scope of this project is to evaluate lifetime curve of common cable insulation material at variable frequency

.>

Problem definition:

Due to the increasing reliance on renewable energy sources (RES), the power system now includes a number of power electronic converters. Other components which the network comprises of, face a major challenge due to voltage and current harmonics these converters induce. Presence of harmonics lead to higher losses, uneven concentration of electric stress, and a rise in temperature. These occurrences induce an uncertainty in the performance of the insulation material of a cable. This project will focus on designing a circuit which generates harmonics which are similar to those in the above mentioned circumstances. The selected insulation material will undergo these harmonics from which we can conclude the effect of harmonics on insulation material.

Methodology:

< Design a resonance circuit capable of generating high voltage high frequency signals. Perform ageing

experiments on common cable insulation material and obtain the lifetime curves at different frequencies.>


• Perform a literature review for the thesis to gain more insight on the topic

• Design and simulate a circuit to generate high frequency signals at high voltage levels.

• Perform aging tests and find out the influence of frequency on lifetime and analyse the results..

• Write the thesis report

Contact details:


Peter Vaessen [email protected]

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TITLE: CONTROL SYSTEM FOR ELECTROSTATIC VOLTMETER


Scope:

<The goal is to construct a control unit for electrostatic voltmeter to measure potential distribution along a surface. The device will then be used to measure surface charge decay over commonly used dielectrics.>

Problem definition:

< Surface charges may accumulate on the surface of DC insulator and alter electric field distribution. In gas insulated substations due to field emission from the enclosure, electric charges are injected to SF6 and deposits on the surface of the spacer. In outdoor polymeric insulator surface charges are formed on the insulator due to corona activity. The presence of surface charges may decrease the breakdown strength of the insulator, leading to failure of HVDC component (in the event of lightning impulses) and hence interrupting power transmission. Therefore understanding how surface charges form and decay on the surface of insulator is very important for HVDC insulation design. HV laboratory has recently bought an electrostatic voltmeter. The voltage probe must be mounted a 2 axis CNC unit to scan the surface potential at a fix distance between the probe and the plate. Proper rails, bearing and stepper motors, type of microcontroller, together with flexible control algorithm (speed of scan, initial point setting) must be purchased, programmed and constructed. The final product will be used to measure surface charge decay over commonly used dielectric materials.>

Methodology:

<Proper components for a 2 axis CNC control unit must be chosen and purchased. A code must be written to control the stepper motors with the required flexibility. Final product should be assembled and used to measure charge decay over known dielectric sample. The results of the measurement must be compared with literature.>


• <Purchasing the proper components for 2 axis CNC unit and development of the control code>

• <Assembling of the product and testing its performance by means of surface charge decay over known dielectric material and comparison with literature.>

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• <Writing the final report and user manual for the developed device.>

Contact details:

• Supervisor: <Mohamad Ghaffarian Niasar, [email protected]>

• Rob Ross, [email protected], Peter Vaessen [email protected]

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TITLE: DESIGN AND PROTOTYPING A SOLID STATE MARX IMPULSE GENERATOR

Type of project: Master thesis

Traditional Marx generator Solid state monopolar pulse generator

J. Rao, et. al, “All Solid-State Rectangular Sub-Microsecond Pulse Generator for Water Treatment Application”, IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 46, NO. 10, OCTOBER 2018

Scope:

To design, model and prototype a 10 kV solid state Marx impulse generator.

Problem definition:

TU Delft and KEMA laboratories are collaborating to create a universal high voltage test source capable of generating arbitrary waveforms including lightning impulses. The high current passed through the switches and the electromagnetic disturbances created during the lightning impulse impose limitation on switch sizing and required shielding of the communication and control system of the test generator. To identify challenges related to actual design of the high voltage arbitrary waveform generator, in this project a solid state 10 kV impulse generator will be designed, modelled and prototyped.

Methodology:

Accurate Spice/ Simulink model of the impulse generator including the important parasitic components will be made. This is check influence of different design parameters and to avoid overstress of switches during operation. Based on the simulation result, 3 stages of the pulse generator will be made and tested. At this stage isolation is created by means of 20 kV fast opt-coupler. Upon successful achievement in the first part, synchronization method will be replaced by fibre optics or laser pulses and the full scale test generator will be developed.


• Literature review of different topology used in solid state pulse generators

• Simulation of the Marx pulse generator considering parasitic parameters. Calculate voltage distribution along the stages of the generator.

• Prototyping and testing the developed solid state impulse generator

Contact details:

• Supervisor: Mohamad Ghaffarian Niasar, [email protected]

• Tiago Batista Soeiro, [email protected]

• Peter Vaessen, [email protected]

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TITLE: LIGHNING IMPULSE VOLTGAE DISTRIBUTION IN DISK TYPE WINDING


Scope:

< Study on the lightning voltage distribution in the next generation of transformers and reactors.

Problem definition:

<Part of the factory acceptance test for extra high voltage transformers and reactors is Lightning Impulse (LI) testing. During such test, the voltage distribution along the winding depends on electrical parameters of the winding (capacitance, inductance and resistance). The later, in turn, are related to the physical dimensions of the winding and the ratings of the transformer. It is widely known that the lightning impulse voltage does not distribute linearly along the winding. The challenge lies in understanding the details of voltage distribution across the winding during the lightning impulse. As an example, a 230 kV reactor can contain up to 2000 meters of copper wire per winding. Such length in combination with very short rise-time of a lightning impulse might additionally introduce the travelling wave effect and oscillations within the winding.

Methodology:

Major steps are:

• Literature study on the transient behaviour within transformer windings.

• Inventory of parameters governing the voltage distribution along the winding during LI test.

• Winding model development and simulation of the LI voltage distribution.

• Measurement of LI voltage distribution on a real winding and model verification.


<Develop a tool/model which will help to determine the LI voltage distribution along the winding of

when considering dimensions and number of turns differ.>

Contact details:


Peter Vaessen, [email protected]

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TITLE: PD MEASUREMNET ON MECHANICALLY AGED DIELCTRIC ELASTORMERS


Scope:

< The scope of the project is to assess which is the influence of repetitive mechanical stretching on ageing of

silicon elastomer material that is typically used in artificial muscles or energy wave harvesting.>

Problem definition:

< Dielectric electroactive polymers (DEAP) are a class of smart insulating material used in actuators or energy

harvesting devices. When a DEAP is exposed to high electric fields, it deforms due to Coulomb forces created on its surface. This translates in transforming energy from an electrical domain to a mechanical one. And vice versa, since reversibility of the process.

During its operational lifetime, such material must undergo a huge number of deformation cycles. Therefore it is important to know which is the impact of pure repetitive mechanical stress on mechanical and dielectric properties of the material.>

Methodology:

<The project is divided into two phases: first, is to work with mechanical stretcher device and learn how to

prepare dielectric elastomer samples. Second application of repetitive stretching cycles to actual silicone specimens and observation of possible changes in permittivity, tangent delta, partial discharges used as ageing indicator.>


• Finding a relation between mechanical cycle stress and dielectric changes.

• Understanding how rapid is the mechanical degradation for such system.

Contact details:


Rob Ross, [email protected]

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TITLE: STUDY OF TRICHEL PULSES IN AIR

Type of project: < Extra Project>

Scope:

<To numerically model negative corona (Trichel pulses) in air using COMSOL Multiphysics software and Matlab. The aim is to control solver’s step size during the whole simulation to minimize the simulation time.>

Problem definition:

<High electric field around sharp points can cause local breakdown of air known as corona discharge. If the polarity of applied voltage is negative and the dielectric medium has electronegative gas (such as oxygen) repetitive pulses of the same magnitude is usually observed during corona discharge. The goal of this project is to solve hydrodynamic equations of charged particles coupled with Poisson’s equation, to model the so called Trichel pulses in 2D-axis symmetric domain. Proper meshing, type of solver and step size taken by the solver are important parameters. In this extra project it is expected that the model is controlled from Matlab and proper algorithm is developed to control step size during the whole simulation in order to lower the simulation time.

Methodology:

<The work is simulation based and can be performed on the high end computer available in HV laboratory. Experimental verification has to be done when a functional model is developed>


• <literature review, getting use to the existing model (how is it made, boundary conditions, functionality and limitations)>

• <Implementing and controlling the existing COMSOL model by Matlab. Identifying the most suitable meshing strategy and controlling solver’s step size to obtain shorter simulation time

Contact details:

• Supervisor: < Mohamad Ghaffarian Niasar, [email protected]>

Rob Ross, [email protected], Peter Vaessen [email protected]

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High voltage DC Diagnostics and Monitoring DC systems, Energy conversion & Storage

DEVELOPMENT OF A PD RECOGNITION SYSTEM FOR HVDC GIS BASED ON MAGNETIC ANTENNAS


Scope:

To develop a recognition system for partial discharges (PD) occurring in High Voltage DC (HVDC) gas insulated system (GIS) based on a new magnetic antenna.

Problem definition:

PD measurement plays an important role in the monitoring and diagnostic of HVDC GIS due to its high capabilities to detect in-service failures related to defects in the insulation system. PD in a GIS produce electromagnetic waves, which are commonly measured by electric antennas installed in the GIS enclosures. At the High Voltage Lab, a new concept of PD measurements has been developed based on magnetic antennas, having some advantages as PD polarity detection. This new magnetic antenna measures the PD signals in the range of tens of MHz but -unfortunately- is also able to pick up the noise and the electromagnetic disturbances that are traveling across the GIS enclosure. Therefore, it is important to develop a recognition system capable of discriminate noise, external disturbances and partial discharges in an HVDC GIS.

Methodology:

A profound study of the clustering, denoising and discrimination techniques available for transient pulses. Then, the techniques should be implemented and tested using computer algorithms and real measurements in the GIS available at the High Voltage Lab.


• To conduct a literature review.

• To implement clustering, denoising and discrimination techniques by computer algorithms.

• To check the recognition techniques by experimental tests.

Contact details:

• Postdoc researcher: Fabio Muñoz, [email protected]

• Supervisor: Armando Rodrigo Mor, [email protected]

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High Voltage DC Materials and Components


[1] D.A. Ganeshpure, “Modular Multilevel Converter (MMC) based High Voltage Test Source”, Master thesis in Electrical Engineering, Delft University of Technology, 2018

[2] G.P. Lourduraj, “Feasibility study of oil immersed power electronics based high voltage test source for onsite testing purpose”, Master thesis in Electrical Engineering, Delft University of Technology, 2019

TITLE: DESIGN OF CASCADED H BRIDGE (CHB) TOPOLOGY AND ITS SIZE ESTIMATION TO USE AS A HV TEST SOURCE


(a)

(b)

Cascaded H bridge topology Different ways to implement a DC source in CHB topology

Scope: The goal is to design CHB topology to generate arbitrary wave shapes for HV testing and estimate the size of the converter.

Problem definition: TU Delft and KEMA laboratories are collaborating to create a universal high voltage test source capable of generating arbitrary waveforms using multilevel converter topologies. Design of Modular Multilevel Converter (MMC) and its size estimation are performed with two MSc theses [1] [2]. To make a choice of suitable converter topology, the design requirement and size of both converter topologies need to be compared.

Methodology: The main focus of this master’s thesis is to compare different types of DC source implementation. Some of these implementations are shown in figure (a) and (b). This will have a huge impact with respect to the size, complexity, and scalability of the HV test source. Other aspects of design will be similar to the design of MMC.


• Literature review on various options for DC source implementation in CHB

• Size estimation with various chosen options

• Complete design guidelines of CHB topology

Contact details:



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TITLE: FEASIBILITY STUDY ABOUT GENERATING LIGHTNING IMPULSE USING MULTILEVL CONVERTER TOPOLOGIES


Current pulse required for lightning impulse

Scope: The goal is to check if it is possible to generate lightning impulse using multiple converter topologies

Problem definition: TU Delft and KEMA laboratories are collaborating to create a universal high voltage test source capable of generating arbitrary waveforms using multilevel converter topologies including lightning impulse. The lightning impulse wave shape and required current rating with 10 nF capacitive load is shown in figure. To achieve this using multi converter topologies, there are two major unknown problems which are current rating of switches and operating all switches together within 1 µs. First aim of this project is to investigate if it is possible to use lower current rated switches for short current pulse. Second aim is to check if it is possible to fire all switches together to get desired dv/dt across the capacitive load.

Methodology: From a previous work, it has understood that the NPT type of 50 A rated IGBTs saturates at 150 A and therefore they cannot be used for lightning impulse. Hence, the first part of the project will include testing different types of IGBTs on an already developed prototype. Then, the two cells of MMC will be stacked, and gate driver will be tuned to achieve the required dv/dt across a capacitive load.


• Literature review on types of IGBTs and their dynamic behaviour

• Pspice simulation of setup for generating short current pulse

• Build 2 MMC cells and operate it with a capacitive load

• Tune the gate driver circuitry to obtain desired dv/dt across the load

Contact details:



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High Voltage DC Materials and Components DC systems, Energy conversion & Storage

DESIGN OF HIGH VOLTAGE SUPERCONDUCTING TRANSFORMER

Type of project: Extra Project/ MSc Thesis

Superconducting transformer (left) and copper transformer (right) with comparable nominal power (medium voltage traction transformer)

Source: M. Noe, EUCAS Short Course: Superconducting transformer

Scope:

The scope of this project is to develop a finite element (FEM) model and design a high voltage superconducting transformer.

Problem definition:

Superconductors are materials that can conduct a stationary electrical current without resistance. Higher current carrying capability of the superconductors provide a great opportunity to reduce the size of the power

components. The size and weight of the component become an important factor in dense areas. Physics and working temperature of the superconducting materials are different. Modelling the physics and behaviour of the material require good understanding. Several numerical approaches to model the superconducting material has been developed. Applying those numerical approaches to design a component is the goal of this project.

Methodology:

The work is mostly focused on modelling and preliminary design of high voltage superconducting transformers. Analytical design and FEM design of the transformer to predict the losses and size of the transformer is expected.



• To be able to couple different physics in COMSOL Multiphysics software and build a physics of superconductor

• Development of a FEM model that can accurately predict the electrical parameter of the transformer

• Comparison between FEM and analytical design of the transformer

Contact details:

• Babak Gholizad, [email protected]

• Rob Ross, [email protected]

D C E & S

DC Systems, Energy Conversion & Storage 1



REPLACEMENT STRATEGY FOR GAS-PRESSURIZED UNDERGROUND CABLE SYSTEMS

Type of project: MSc Thesis

Scope:

The scope of this project is to understand the effect of thermal aging of insulation on the lifetime of electrical insulation systems in the power system grid.

Problem definition:

The electrical insulation system ages because of different stresses. Electrical, mechanical, chemical, and thermal stresses are the main causes of aging. The loading profile of the power component changes the operating temperature of the insulation system. 10°C increase in working temperature of insulation reduces the thermal lifetime of the insulation by half. Dynamic loading of the cables and excess of energy demands requires higher loading of the power component which translates the higher working temperature of the insulation material.

The relation between thermal aging and the lifetime of the power components is not well-known. This project

aims to understand this relation. The results of the project will use to build a replacement strategy for gas-pressurized cables in the TenneT grid.

Methodology:

The work is consist of experimental and modeling task to understand the impact of thermal aging on the lifetime of the power system components.



• Modeling of thermal profile of the power component

• Preparing experimental set-up

• Studying the relationship between thermal aging and lifetime of the insulation using an experimental set-up

Contact details:

• Babak Gholizad, [email protected]

• Rob Ross, [email protected]

Gas Pressurised Cable

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LOSSES MODEL OF HIGH POWER HIGH FREQUENCY TRANSFORMER


Scope:

The goal is to develop a loss model that can estimate copper/core/dielectric losses, of high power high frequency transformer.

Problem definition:

High frequency transformer is vital part of isolated power converters. As the development of semiconductor devices, power converters’ rates become larger, correspondingly high frequency transformer become several hundred kilowatts. Due to the high frequency operating waveform, the magnetic part of transformers can scale down hugely, which obviously make the transformer much smaller and lighter. However, small size always means poor dissipation rate, plus the power rates don’t change, heat in transformer would accumulate and cause severe consequences. So accurate loss evaluation is necessary in design process.

Methodology:

The project needs to simulate copper/core/dielectric losses of high frequency transformers under typical working condition through MATLAB and FEM software like COMSOL. And verify the model through experiment in HV lab.


• Literature review of the existing loss model under high frequency.

• Develop analytical and FEM models for estimating different losses of high frequency transformer.

• Verify the loss model through experiment.

Contact details:

• PhD student: Tianming Luo, [email protected]， Skype ID: live:2622634035

• Supervisor: Mohamad G Niasar, [email protected]

Peter Vaessen [email protected]

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PARTIAL DISCHARGE AND LIFE BEHAVIOR OF EPOXY UNDER HIGH DV/DT


Scope:

The goal is to access the lifetime curves and PD performances of epoxy insulation under different dV/dt conditions through experiments.

Problem definition:

Due to higher block voltage and switching frequency of semiconductor devices, like SiC MOSFET, the insulation material would suffer higher voltage ramp rate (dV/dt). According to existing experience, high voltage ramp rate threatens reliability of insulation materials. In order to evaluate the impacts, the lifetimes and partial discharge performances under different ramp rates will be tested and analysed.

Methodology:

The project needs to establish a platform for testing lifetime and PD. This platform should be able to modulate the voltage ramp rate and other related parameters. After that, epoxy resin sample will be tested and analysed. The experiment will be done in the HV lab.


• Literature review of lifetime and PD under different voltage stress.

• Establish the experimental setup.

• Study the relationship between lifetime, PD and voltage ramp rate.

Contact details:

• PhD student: Tianming Luo, [email protected]， Skype ID: live:2622634035

• Supervisor: Mohamad G Niasar, [email protected] Peter Vaessen [email protected]

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TITLE: DESIGN OF LOW VOLTAGE MULTI-LEVEL CASCADED H-BRIDGE, CONTROLLED AND PROGRAMMED OVER WI-FI

Type of project: Extra project/Master thesis

H-Bridge and gate driver

DC/DC

AC/DC MC


DC/DC

AC/DC MC


DC/DC

AC/DC MC

25 kHz high current H-bridge

DC Source

3 level cascaded H-bridge converter

Scope:

To design and prototype a low voltage multilevel cascaded H-bridge converter with separate microcontroller on each stage controlled and programmed over Wi-Fi and synchronized by a master microcontroller.

Problem definition:

TU Delft and KEMA laboratories are collaborating to create a universal high voltage test source capable of generating arbitrary waveforms. Multilevel cascaded H-Bridge topology is one of the candidate for the final topology of this test generator. Since the final test generator has many stages, it is convenient to avoid lots of fiber optic connections for the communication system. Low cost low voltage motor driver, Wi Fi Arduino, isolating transformers and DC/DC converters will be used to develop the sub-module. Each sub-module will be made with its own Wi Fi equipped microcontroller. The goal is to code the microcontroller over Wi Fi and to generate the desired output waveform. Synchronization of the microcontrollers is done using a master microcontroller.

Methodology:

To construct low voltage sub-module of a multilevel cascaded H-bridge using low cost components. To develop control and communication system with Wi-Fi equipped microcontroller.


• To construct sub-module of multilevel cascaded H-bridge converter

• To programme the microcontroller over Wi-Fi

• To control and synchronize three stages of the test generator using a master microcontroller

Contact details:

• Supervisor: Mohamad Ghaffarian Niasar, [email protected]

• Tiago Batista [email protected]

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TITLE: THERMAL MODELLING OF OIL IMMERSED POWER CONVERTERS


Scope:

<The goal of this project is to identify possible degradation and failure mechanisms of power switches induced by long term oil exposure>

Problem definition:

<DNVGL in cooperation with DCE&S group aims to build a power electronic based high voltage arbitrary waveform test generator. The ultimate goal is to immerse this test generator under oil in order to reduce the size of the device. This is important since the test generator can be used for mobile testing purposes. To long term ensure reliable operation of the test generator, it is necessary to identify any possible degradation mechanism of power switched due to long term oil exposure. Initial study was performed by previous master student and interesting observation has been made. In this work we want to expand the previous research.

Methodology:

<different power switches will be aged thermally and electrically under oil and in air. Various of characterization methods will be used before and after each aging test. The difference of characterization between oil-immersed switches and air exposed switches will be used to identify possible degradation mechanism induced by oil>


• <Literature review of power switches internal structure and failure mechanisms>

• <Expanding the existing setup for aging of oil-immersed power switches>

• <Interpretation of the results and writing final report>

•

Contact details:

• Supervisor: <Mohamad Ghaffarian Niasar, [email protected]>

• Peter Vaessen [email protected]

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HIGH TEMPERATURE SUPERCONDUCTIVITY FOR DEGAUSSING


Scope:

Due to their permeability, naval ships distort Earth’s magnetic field. These anomalies in the magnetic field can be detected by sensors attached to airplanes or, even worse, magnetic mines. Luckily, there are methods to prevent detection by making ships “magnetically invisible”. One of these methods is to install a degaussing system, a set of coils designed to induce a magnetic field which compensates for the distortion.

Problem definition:

Nowadays, degaussing coils are made out of copper. Due to energy losses and weight issues, however, it might be better to use a superconductive material. Moreover, the developments in high temperature superconductivity (HTS), makes the use of superconductors a serious option.

In superconductive coils, the current density can be much higher than in copper coils. Therefore, a superconductive degaussing coil can have a higher amount of Ampere turns and a lower amount of turns than a copper degaussing coils. This will cause an increase in the power supply, however. The aim of this thesis is to find a suitable power electronic topology to supply the higher degaussing current without too much losses.

Methodology:

In this project a model should be built to simulate the differences of superconductive coils and degaussing coils. A test setup can be built to test the power supply topology.


• To conduct a literature review

• To obtain a model of superconductive coils and a power system

• To define and test an experimental test set-up

Contact details:

• PhD student: Djurre Wikkerink, [email protected]

• Supervisors: Prof. Rob Ross, [email protected] Dr. Armando Rodrigo Mor, [email protected]

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