Power ElectronicsPower Electronics

Chapter 1

Introduction

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OutlineOutline

I.I. What is power electronics?What is power electronics?

II.II. The historyThe history

III.III. ApplicationsApplications

IV.IV. A simple exampleA simple example

V.V. About this courseAbout this course

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I.I. What is power electronics?What is power electronics?

1)1) DefinitionDefinition

2)2) Relation with information electronicsRelation with information electronics

3)3) The interdisciplinary natureThe interdisciplinary nature

4)4) Position and significance in the human societyPosition and significance in the human society

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Power ElectronicsPower Electronics::

A more exact explanationA more exact explanation::

is the electronics applied to conversion and control of

electric power.

Range of power scale :Range of power scale :

milliwatts(mW) megawatts(MW) gigawatts(GW)

1)1) DefinitionDefinition

The primary task of power electronics is to process and

control the flow of electric energy by supplying voltages

and currents in a form that is optimally suited for user

loads.

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Conversion of electric powerConversion of electric power

Other names for electricOther names for electric power converter:power converter: -Power converter -Converter -Switching converter -Power electronic circuit -Power electronic converter

Electric

Power

Converter

PowerPoweroutputoutput

PowerPower inputinput

Control Control inputinput

Frequency, magnitude,Frequency, magnitude,

number of phasesnumber of phasesAC (Alternating Current)AC (Alternating Current)

MagnitudeMagnitudeDC(Direct Current)DC(Direct Current)

Changeable properties in Changeable properties in conversion conversion Two types of electric powerTwo types of electric power

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Classification of power convertersClassification of power converters

DCDC ACAC

AC AC to DC converter (Rectifier)

AC to AC converter

( Fixed frequency : AC controller

Variable frequency: Cycloconverter or frequency converter)

DC DC to DC converter (Chopper)

DC to AC converter

(Inverter)

Power outputPower output

Power inputPower input

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Power electronic systemPower electronic system

Generic structure of a power electronic systemGeneric structure of a power electronic system

Power

Converter

Power output

Power input

ControllerFeedforward/Feedback Feedback/Feedforward

Reference

(commanding)

( ( measurements of output measurements of output signals )signals ) ( measurements of input

signals )

Control is invariably required. Power converter along with its controller including the

corresponding measurement and interface circuits, is

also called power electronic system.

Control input

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Typical power sources and loads Typical power sources and loads for a power electronic systemfor a power electronic system

The task of power electronics has been recently extended to also ensuring the currents and power consumed by power converters and loads to meet the requirement of electric energy sources.

-Electric Motor

-light

-heating-power converter -other electric or electronic equipment

PowerPower ConverterConverter

SourceSourcePower inputPower input Power outputPower output

LoadLoad

ControllerControllerReferenceReference

-Electric utility-battery-other electric energy source -power converter

Vi i i i o Vo

Feedback/Feedback/

Feed forwardFeed forward

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A Classification of electronics by processing objectA Classification of electronics by processing object

2)2) Relation with information electronicsRelation with information electronics

ElectronicsElectronicsInformation electronics: to process information Information electronics: to process information

Power electronics: to process electric powerPower electronics: to process electric power

Other classifications of electronicsOther classifications of electronics

ElectronicsElectronics

Vacuum electronics: using vacuum devices,Vacuum electronics: using vacuum devices, e.g, vacuum tubes devicese.g, vacuum tubes devices

Solid (Solid state) electronics: using solid state devices,Solid (Solid state) electronics: using solid state devices, e.g, semiconductor devicese.g, semiconductor devices

ElectronicsElectronics

Applied electronics: application of electronicApplied electronics: application of electronic devices to various areas devices to various areas

Physical electronics: physics,material,fabrication, Physical electronics: physics,material,fabrication, and manufacturing of electronicand manufacturing of electronic devicesdevices

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3)3) The interdisciplinary natureThe interdisciplinary nature

William E. Newell’s descriptionWilliam E. Newell’s description

Electronics

Dev

ices

,circ

uits Power

Static &

rotating

power equipm

entPower

Electronics

Continuous, Continuous,

discretediscrete Control

Power electronics is the interface betweenPower electronics is the interface between

electronics and power.electronics and power.

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Relation with multiple disciplines Relation with multiple disciplines

Power electronics is currently the most active Power electronics is currently the most active discipline in electric power engineering worldwidediscipline in electric power engineering worldwide. .

PowerPowerelectronicselectronics

Systems & Systems & Control theoryControl theory

Circuit Circuit theorytheory

Signal Signal processing processing

Simulation & Simulation & computingcomputing

ElectronicsElectronics

Solid state Solid state physicsphysics

ElectromagneticsElectromagnetics

Power Power systemssystems

Electric Electric machinesmachines

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4)4) Position and significance Position and significance in the human society in the human society

Electric power is used in almost every aspect and Electric power is used in almost every aspect and everywhere of modern human society.everywhere of modern human society.

Electric power is the major form of energy source used in Electric power is the major form of energy source used in modern human society.modern human society.

The objective of power electronics is exactly about how to The objective of power electronics is exactly about how to use electric power, and how to use it effectively and use electric power, and how to use it effectively and efficiently, and how to improve the quality and utilization efficiently, and how to improve the quality and utilization of electric power.of electric power.

Power electronics and information electronics make two Power electronics and information electronics make two poles of modern technology and human society—— poles of modern technology and human society—— information electronics is the brain,and power electronics information electronics is the brain,and power electronics is the muscle.is the muscle.

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II.II. The historyThe history

The thread of the power electronics history precisely follows and The thread of the power electronics history precisely follows and matches the break-through and evolution of power electronic devicesmatches the break-through and evolution of power electronic devices

late 1980slate 1980smid 1970smid 1970s1957195719001900

Mercury arc rectifier Mercury arc rectifier Vacuum-tube rectifier Vacuum-tube rectifier

Thyratron Thyratron

Invention of Invention of Thyristor

Power diode Power diode ThyristorThyristor

ApplicaApplication of ion of fast-switching fast-switching fully-controlled fully-controlled semiconductor semiconductor devicesdevices GTOGTO

GTRGTRPower MOSFET Power MOSFET

ThyristorThyristor(microprocessor)(microprocessor)

IGBTIGBTPower MOSFETPower MOSFET

ThyristorThyristor(DSP)(DSP)

Pre-historyPre-history 1st phase1st phase 2nd phase2nd phase 33rd phaserd phase

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III.III. ApplicationsApplications

IndustrialIndustrial

TransportationTransportation

Utility systemsUtility systems

Power supplies for all kinds of electronic equipmentPower supplies for all kinds of electronic equipment

Residential and home appliancesResidential and home appliances

Space technologySpace technology

Other applicationsOther applications

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Industrial applicationsIndustrial applications

Motor drivesMotor drives

ElectrolysisElectrolysis

ElectroplatingElectroplating

Induction heatingInduction heating

WeldingWelding

Arc furnaces and ovensArc furnaces and ovens

LightingLighting

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Transportation applicationsTransportation applications

Trains & locomotivesTrains & locomotives

SubwaysSubways

Trolley busesTrolley buses

Magnetic levitationMagnetic levitation

Electric vehiclesElectric vehicles

Automotive electronicsAutomotive electronics

Ship power systemsShip power systems

Aircraft power systemsAircraft power systems

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Utility systems applicationsUtility systems applications

High-voltage dc High-voltage dc transmission(HVDC)transmission(HVDC)

Flexible ac transmission(FACTS)Flexible ac transmission(FACTS)

Static var compensation & Static var compensation & harmonics suppression: TCR, TSC, harmonics suppression: TCR, TSC, SVG, APFSVG, APF

Custom power & power quality Custom power & power quality controlcontrol

Supplemental energy sources :Supplemental energy sources :

wind, photovoltaic, fuel cellswind, photovoltaic, fuel cells

Energy storage systemsEnergy storage systems

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Power supplies for electronic equipmentPower supplies for electronic equipment

TelecommunicationsTelecommunications

ComputersComputers

Office equipmentOffice equipment

Electronic instrumentsElectronic instruments

Portable or mobile Portable or mobile electronicselectronics

serverservercomputercomputer

TelecommunicationTelecommunication

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Residential and home appliancesResidential and home appliances

LightingLighting

HeatingHeating

Air conditioningAir conditioning

Refrigeration & freezersRefrigeration & freezers

CookingCooking

CleaningCleaning

EntertainingEntertaining

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Applications in space technologyApplications in space technology

Spaceship power systemsSpaceship power systems

Satellite power systemsSatellite power systems

Space vehicle power Space vehicle power systemssystems

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Other applicationsOther applications

Nuclear reactor controlNuclear reactor control

Power systems for Power systems for particle acceleratorsparticle accelerators

Environmental Environmental engineeringengineering

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TrendsTrends

It is estimated that in developed countries now 60% of the electric energy goes through some kind of power electronics converters before it is finally used.

reduction of energy consumption leads to less pollution

reduction of pollution produced by power converters

direct applications to environment protection technology

Power electronics has been making major

contributions to: --better performance of power supplies and better control of electric equipment

--energy saving

--environment protection

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IV.IV. A simple exampleA simple example

A simple dc-dc converter exampleA simple dc-dc converter example

Input source:100VInput source:100V

Output load:50V, 10A, 500WOutput load:50V, 10A, 500W

How can this converter be realized?How can this converter be realized?

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Dissipative realizationDissipative realization

Resistive voltage dividerResistive voltage divider

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Dissipative realizationDissipative realization

Series pass regulator:Series pass regulator:

transistor operates in active regiontransistor operates in active region

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Use of a SPDT switchUse of a SPDT switch

SPDT: Single pole double throwSPDT: Single pole double throw

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The switch changes the dc voltage levelThe switch changes the dc voltage level

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Addition of low pass filterAddition of low pass filter

Addition of (ideally lossless) L-C low-pass filter, for Addition of (ideally lossless) L-C low-pass filter, for removal of switching harmonics:removal of switching harmonics:

Choose filter cutoff frequency Choose filter cutoff frequency ff0 0 much smaller than much smaller than switching frequency switching frequency ffss

This circuit is known as the “buck converter”This circuit is known as the “buck converter”

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Addition of control system for Addition of control system for regulation of output voltageregulation of output voltage

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Major issues in power electronicsMajor issues in power electronics

How to meet the requirement of the load or gain better How to meet the requirement of the load or gain better control of the loadcontrol of the load

How to improve the efficiency How to improve the efficiency --for reliable operation of power semiconductor --for reliable operation of power semiconductor

devices devices --for energy saving--for energy saving

How to realize power conversion with less volume, less How to realize power conversion with less volume, less weight, and less costweight, and less cost

How to reduce negative influence to other equipment in How to reduce negative influence to other equipment in the electric power system and to the electromagnetic the electric power system and to the electromagnetic environmentenvironment

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V.V. About this courseAbout this course

Relation with other coursesRelation with other courses

PowerPowerelectronicselectronics

FundamentalsFundamentals of analog / digitalof analog / digital

electronicselectronics

Pre-requisite coursePre-requisite course

Control systemsControl systemsfor electric for electric

drivesdrives

Continuing courseContinuing course

Four parts of the contentFour parts of the content

Power electronic devices: Power electronic devices: Chapter 2 and 9Chapter 2 and 9

Power electronic circuits: Power electronic circuits: Chapter 3, 4, 5 and 6Chapter 3, 4, 5 and 6

Control techniques: Control techniques: Chapter 7 and 8Chapter 7 and 8

Applications: Applications: Chapter 10 Chapter 10

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ArrangementArrangement

Text booksText books - - 王兆安，刘进军。《电力电子技术》。北京：机械工业出版社，王兆安，刘进军。《电力电子技术》。北京：机械工业出版社，

20020099 - - N. Mohan, T. M. Undeland, W. P. Robbins. Power edectronics: N. Mohan, T. M. Undeland, W. P. Robbins. Power edectronics:

converter, applications, and Design, 3rd edition, John Wiley converter, applications, and Design, 3rd edition, John Wiley & & Sons, New York, 2003, Higher Education Press, Beijing, Sons, New York, 2003, Higher Education Press, Beijing, China, China, 20042004

LecturesLectures - 48 hours , all in English- 48 hours , all in English - After-class reading in Chinese and English will be assigned.- After-class reading in Chinese and English will be assigned.

Labs Labs - 8 hours, 5 projects- 8 hours, 5 projects