04/11/2023 ICAER 2013

Performance Analysis of Single Phase Photovoltaic Inverter Topologies and

Implementation of Piccolo Series Controller TMS320C28027 based

Pulse Width Modulated Signal for Single Phase Bidirectional High Frequency Link Inverter

Prashant V. Thakre, Associate Prof. SSBT College of Engg. & Technology, Jalgaon, Maharashtra

Dr. Saroj Rangnekar, Prof. & Head,Energy Dept., MANIT, Bhopal

1

04/11/2023 ICAER 2013 2

INDEX• Introduction• Problem Formulation• Methodology Adopted• Literature Review• Overview of Thermal & Solar Photovoltaic System• Solar Tracking System• Types of Solar Photovoltaic System• Inverter Topologies• Modeling of Closed Loop System• Simulink Models• Experimental Setup• Conclusion• References

04/11/2023 ICAER 2013 3

IntroductionWith the growing energy demand, increasing global environmental issues, and depleting energy resources such as coal, oil and gas, the need to develop and utilize new sources of energy seems inevitable. Therefore renewable energy resources such as solar, wind, biomass, hydro and geothermal etc appear as important alternative energy options. Solar energy is one of the few clean and abundant renewable energy resource which is being use extensively in recent years.

04/11/2023 ICAER 2013 4

Energy demand projection in India [www.mnre.gov.in]

04/11/2023 ICAER 2013 5

Introduction

• Worldwide lot of work on solar technology is going on even in the countries where there is limited sunshine over the year. India is blessed with a bright sunshine round the year. With the advancement in control techniques, solar energy is becoming one of the alternate renewable energy sources for generation of power.

04/11/2023 ICAER 2013 6

Introduction

• Today, with the explosive growth and expanding efficiency of digital technology, digital inverter system is having edge over analog systems. Microprocessors, Microcontrollers and Digital Signal Processors (DSP) have been used for Pulse Width Modulation (PWM) pulse generation and real-time controller of inverter systems

04/11/2023 ICAER 2013 7

Aims and Objectives

• Study and implementation of maximum peak power tracking system

• Study of various control techniques for PWM inverters• MATLAB/Simulink model of closed loop boost converter• Selecting appropriate control technique for the BHFL solar

photovoltaic inverter• Analytical modeling of the BHFL solar photovoltaic inverter

and controller design• System Testing• Hardware implementation• Test and results

04/11/2023 ICAER 2013 8

Problem formulation

• Identifying the solar tracking methods for maximum power output.• Mathematical modeling of selected tracking system for maximum power point

tracking• Development of MATLAB/Simulink models for solar photovoltaic system.• Design and developing inverter models & PWM generations using

MATLAB/Simulink • Testing the developed models with different test conditions. • Selecting the suitable model based on amount of total harmonic distortion,

voltage and current waveforms and switching frequencies, for implementing hardware circuit for inverter.

• Designing and development of hardware circuit for selected solar photovoltaic inverter model.

• Development of algorithm for generating PWM signals in real time.• Interfacing of digital controller to PC for uploading the software for generating

the PWM signals.• Testing the digital controller based solar photovoltaic system in real time mode.

04/11/2023 ICAER 2013 9

Methodology Adopted

• Development of mathematical models for solar photo voltaic system.

• Development of inverter models & PWM generations using MATLAB/Simulink.

• Testing of models with different switching frequencies.• Development of algorithm for generating PWM signals in

case of real time analysis.• Interfacing of DSP kit to PC for uploading the software

project for generating the PWM signals. • Development of hardware model for BHFL solar photovoltaic

inverter with appropriate driver circuit.• Interfacing BHFL inverter to solar panel.• Implementation of maximum peak power tracking system

04/11/2023 ICAER 2013 10

Solar Tracking System (P&O Method)

Where Iph is the current generated from photon as a function of temperature and solar irradiation,Isat is the saturated reverse current, q is the charge on electron, A is the ideality factor, K is the Boltzmann’s Constant, T is the temperature, rs is the series resistance

The voltage corresponding to the maximum power given to the panel is dependent on solar irradiation and on temperature

04/11/2023 ICAER 2013 11

Solar Tracking System

The light generated current and the saturated reverse current is expressed as

Where Tr is the reference temperatureEg is the energy band gapIscr is the short circuit current at reference temperatureKI is the current temperature coefficientS is per unit irradiationIrr is the reverse current at reference temperature

04/11/2023 ICAER 2013 12

Solar Tracking SystemMaximum peak power is found by solving the following equation

The optimal voltage Vm is used to consider the voltage perturbation given by equation

04/11/2023 ICAER 2013 13

Types of Solar Photovoltaic Systems

Solar photovoltaic system is classified as :

a) Grid-connected solar PV systems

b) Stand Alone System

04/11/2023 ICAER 2013 14

Transformer isolated high-frequency link inverter

04/11/2023 ICAER 2013 15

Modeling of closed loop BHFL Inverter

04/11/2023 ICAER 2013 16

Equivalent circuit of the BHFL inverter

04/11/2023 ICAER 2013 17

Modeling of closed loop BHFL Inverter

04/11/2023 ICAER 2013 18

Modeling of closed loop BHFL Inverter

04/11/2023 ICAER 2013 19

Modeling of closed loop BHFL Inverter

Also equation are expressed as

the values of rl & rc are assumed to be very small & are neglected .Thus

equation becomes

04/11/2023 ICAER 2013 20

Modeling of closed loop BHFL Inverter

Based on the equations a dynamic model of the system is represented by block diagram as shown

04/11/2023 ICAER 2013 21

Modeling of closed loop BHFL Inverter

Since the controller is to be implemented using a digital processor ,the continuous time space equations are converted into discrete form .The discrete time state space equations with sampling period of Ts are represented as

04/11/2023 ICAER 2013 22

Modeling of closed loop BHFL InverterWhere

04/11/2023 ICAER 2013 23

Modeling of closed loop BHFL Inverter

The discrete time equation are rewritten as:

From equations, it is observed that additional disturbance terms appear due to discretisation of modal. As compared with continuous time modal shown , there exist two disturbances instead of one, acting on inductor current and output voltage.

04/11/2023 ICAER 2013 24

Modeling of closed loop BHFL InverterThe current & voltage disturbances are represented by the equation,

04/11/2023 ICAER 2013 25

Modeling of closed loop BHFL InverterBased on the above equations the digital model are represented by a block diagram as shown where Z-1 is unit delay.

04/11/2023 ICAER 2013 26

Modeling of Solar Photovoltaic Cell(MATLAB/Simulink model of PV cell)

04/11/2023 ICAER 2013 27

Simulink Model of Solar Photovoltaic System

04/11/2023 ICAER 2013 28

MATLAB/Simulink model of closed loop boost converter

04/11/2023 ICAER 2013 29

Solar PV Inverter model with pulse generator using MATLAB/Simulink

04/11/2023 ICAER 2013 30

Solar PV Inverter model with PWM generation

04/11/2023 ICAER 2013 31

Solar PV Inverter model with bipolar scheme

04/11/2023 ICAER 2013 32

Solar PV Inverter model with unipolar switching scheme

04/11/2023 ICAER 2013 33

Solar PV Inverter model with 1800 mode

04/11/2023 ICAER 2013 34

Model of single phase BHFL solar PV inverter

04/11/2023 ICAER 2013 35

Model of solar photovoltaic system

04/11/2023 ICAER 2013 36

Stand alone solar photovoltaic system

04/11/2023 ICAER 2013 37

Results and discussion

The simulation and experimental results for a photovoltaic system was carried out. The performance of different types of inverter systems were studied with respect to the photovoltaic input using simulink models. A prototype photovoltaic system for 500VA was also developed and its result were studied and verified. For studying and verifying the prototype hardware model, an advanced digital controller TMS320C28027 of Texas Instruments was considered.

04/11/2023 ICAER 2013 38

Results and discussionInitially the performance of solar cell was studied by using a simulink model. After that the characteristics of solar panel, considering arrays of panel was also tested with the help of MATLAB/simulink model by considering parameters such as insolations, short circuit current and short circuit voltage. The characteristics of solar panel were obtained with the help of algorithm and programming.

04/11/2023 ICAER 2013 39

Output power with different values of insolations

Sr. No. Insolation (w/m2) Iout Vout Output Power(watts)

1) 925 3.914 3.914 15.32

2) 950 9.769 9.769 95.43

3) 975 10.57 10.57 111.8

4) 1000 10.93 10.93 119.4

5) 1025 11.15 11.15 124.4

6) 1050 11.32 11.32 128.2

7) 1075 11.45 11.45 131.2

8) 1100 11.56 11.56 133.2

9) 1125 11.65 11.65 135.8

10) 1150 11.74 11.74 137.7

11) 1175 11.81 11.81 139.4

12) 1200 11.87 11.87 140.9

13) 1340 12.16 12.16 147.9

04/11/2023 ICAER 2013 40

Output power based on rated values of standard panels

Sr. No. Model No. Isc(Amp)

Voc(volts)

Imax(Amp)

Vmax(volts)

Pmax(Watts)

Ipv(Amp)

Vpv(volts)

Output Power(W)

1) BP3230T 8.4 36.7 7.9 29.1 230 18.85 18.85 355.5

2) BP3225T 8.3 36.6 7.7 29.1 225 18.85 18.85 355.5

3) BP3170T 5.2 43.6 4.8 35.6 170 23.18 23.18 537.5

4) BP3215T 8.1 36.5 7.4 29.1 215 18.85 18.85 355.5

04/11/2023 ICAER 2013 41

Output characteristics of boost converter (X axis – Time, Y axis – DC Voltage, Duty ratio, Efficiency)

04/11/2023 ICAER 2013 42

Output of Solar Photovoltaic Inverter System (X axis – Time, Y axis - AC voltage, AC current, input current, duty

ratio, input and output power)

04/11/2023 ICAER 2013 43

Parameters for single phase bidirectional high frequency link inverter

Sr. No. Parameters Values1) DC input voltage Vdc = 230 volts

2) Inductance L1 = 0.166 mH

3) Capacitance C1 = 1 µf

4) Inductance L2 = .5 H

5) Carrier frequency (Stage 1) Fs = 15 KHz

6) Modulation Index (Stage 1) 0.8

7) Carrier frequency (Stage 2) Fs = 1KHz

8) Modulation Index (Stage 2) 0.8

04/11/2023 ICAER 2013 44

Voltage waveform at output of transformer( X axis – Time, Y axis – Voltage)

04/11/2023 ICAER 2013 45

Output voltage waveform of BHFL inverter ( X axis – Time, Y axis – Voltage)

04/11/2023 ICAER 2013 46

THD for single phase full bridge bidirectional high frequency link inverter

04/11/2023 ICAER 2013 47

Output signal with fs = 1.5 KHz

04/11/2023 ICAER 2013 48

Output signal with fs = 2.5 KHz

04/11/2023 ICAER 2013 49

Output signal with fs = 10 KHz

04/11/2023 ICAER 2013 50

Parameters considered for standalone PV system

S.No. Notations Components Value

1) Vdc DC voltage 12 volts

2) C1 Capacitor 110µf

3) L1 Inductor 2.5mH

4) R1 Resistor 0.01ohms

5) C2 Capacitor 4700µf

6) L2 Inductor 5mH

7) R2 Resistor 3 ohms

8) C3 Capacitor 1 µf

9) R3 Resistor .01 ohms

10) C3 Capacitor 1 µf

11) C4 Capacitor 3 µf

12) C5 Capacitor 3 µf

13) R4 Resistor 1 ohm

14) fs Switching frequency 1.5KHz

15) MI Modulation Index 0.8

04/11/2023 ICAER 2013 51

Output current and voltage of standalone PV system(X axis – Time, Y axis – Current and Voltage)

04/11/2023 ICAER 2013 52

Battery Voltage for standalone system

04/11/2023 ICAER 2013 53

THD for standalone PV system

04/11/2023 ICAER 2013 54

% THD Values

S. No. Inverter Topology Fundamental Component(50Hz)

% THD

1) Single Phase PV Inverter with pulse generator

64.25 16.70%

2) Single Phase PV Inverter with bipolar switching

90.99 5.84%

3) Single Phase PV Inverter with unipolar switching

219 5.65%

4) Single Phase BHFL PV Inverter with unipolar switching

179.9 4.95%

04/11/2023 ICAER 2013 55

Hardware specification of the circuitPV Module SpecificationModel No. SLP5 - 12

Rated Power = 5 wattRated Voltage = 17.5 voltsRated Current = 0.3 AmpVoc = 21.6 voltsIsc = 0.34 AmpInsolation = 1000 watt/m2

Battery SpecificationMicrotek DC voltage rating = 12 volts

Rated Current = 7.2 AhInverter Circuit SpecificationIGBT driver (TLP250)IGBT (G4PC60U)

Vcc = 10 – 35 voltsMax. threshold Current (If) = 5 mAMax. output current (Iout) = 1.5 AmpVmax = 600 volts, Imax = 23 AmpOperating Temp. = -55 deg. To +150 deg.

Filter Circuit Specification InductorResistorCapacitor

10 mH22 ohms22 µf

Digital ControllerTMS320C28027 (Texas Instruments) 32 bit CPU, 60 MHz device

On chip flash, SARAMOTP memory, 3.3 volt supply

04/11/2023 ICAER 2013 56

Experimental setup for generating PWM signal

04/11/2023 ICAER 2013 57

PWM signal generated from TMS320C28027

04/11/2023 ICAER 2013 58

Hardware implementation of BHFL inverter

04/11/2023 ICAER 2013 59

Connecting BHFL inverter to TMS320C28027

04/11/2023 ICAER 2013 60

Observed AC Signal

04/11/2023 ICAER 2013 61

Experimental setup of single phase prototype model of BHFL inverter

04/11/2023 ICAER 2013 62

Conclusion

•Based on the output generated by the closed loop boost converter, a MATLAB/Simulink model of BHFL photovoltaic inverter was developed and its output was studied by considering different switching frequencies. It was observed that by increasing the switching frequencies there is an improvement in output signal. The amount of THD for single phase BHFL photovoltaic inverter was found to be 4.95%

04/11/2023 ICAER 2013 63

Conclusion

Hardware ImplementationAfter simulating, testing and observing the output signals of various simulink models a hardware prototype model of photovoltaic bidirectional high frequency link inverter was developed for 500 VA rating. The pwm signals for IGBT’s were generated by using piccolo series dsp processor TMS320C28027. The generated pwm signals from GPIO pins of processor were observed on oscilloscope first and then with proper driver circuit consisting of TLP250, given to IGBT’s. The generated ac output signal was also observed on DSO and then applied to the load.

04/11/2023 ICAER 2013 64

References[1] Texas Instruments, www.ti.com[2] Annual report of Geological Survey of India, 2010-2011, Vol.145, part 9[3] www.portal.gsi.gov.in[4] www.mnre.gov.in[5] www.ogi.com/article/2012/04/ongcreport[6] www.visualdictionary.com[7] www.coalindia.in [8] Akshay Urja, Magazine, Vol No. 6, Issue2, Oct 2012[9] Akshay Urja, Magazine, Vol No. 6, Issue1, July-August 2012[10] Akshay Urja, Magazine, Vol No. 4, Issue6, June 2011[11] Wang Parrbao, Wang Wei Xu, DDian- guo, Li Ming, Takashashi Toshio, “Application of IR digital controller IRMCF143 in photovoltaic inverter system” , Proceedings of 2012 IEEE International C Conference on Power Electronics and Motion Control-ECCE Asia, June 2-5, 2012, China, pp 2042-2046[12] Mazen Abdel- Salam, Adel Ahmed, Ahmed EL-Kousy, Khairy Sayeed, “Design and implementation of standalone residential PV system” , IEEE Jordan Conference on Applied Electrical Engineering and Computing Technologies (AEECT), Jordan, pp 476-482, 2011.

04/11/2023 ICAER 2013 65

References[13] Sameer Khader, “ Modeling and simulation of various inverter circuits for photovoltaic applications” , International Journal of Electrical and Power Engineering, Vol 5, No.2, pp 74-83, 2011[14] Souvik Dasgupta, Sanjib Kumar sahoo, Sanjib kumar Panda, “Single phase inverter control techniques for interfacing renewable energy sources with microgrid” , IEEE transaction on Power Electronics, Vol 26, No. 3, pp 717-731, March 2011. [15] Samuel Vasconcelos, Peter Zacharias, Regine Mallwitz, “Highly efficient single phase transformerless inverters for grid connected photovoltaic system” , IEEE transaction on Industrial Electronics, Vol 57, No. 9, pp 3118-3128, 2011[16] H.Nian, R.Zeng, “Improved Control Stategy for standalone distributed generation system under unbalanced and non-linear loads” , IET Renewable Power Generation, Vol 5, No. 5, pp 323-331, 2011[17] A. Yafaoui., B. Wu and R. Cheung, “Implementation of Maximum Power Point Tracking Algorithm For Residential Photovoltaic Systems”, 2nd Canadian Solar Buildings Conference Calgary, June 10 – 14, 2010.[18] Giuseppe Fedele,Domenico Franscino, “Spectral analysis of a class of DC-AC PWM inverters by Kepteyn Series” IEEE Transaction on power electronics,vol. 25,No. 4, pg.839-849, April 2010 .

04/11/2023 ICAER 2013 66

References[19] E.Karatepe, Sayfaruddin, T. Hiyama, “Simple and high efficiency photovoltaic system under non-uniform operating conditions”, IET Renewable Power Generation Journal, Vol 4, No. 4, pp 354-368, 2010[20] L.Piegari, R.Rizzo, “Adaptive perturb and observe algorithm for photovoltaic maximum power point tracking” , IET Renewable Power Generation Journal, IEEE, Vol 4, No. 4, pp 317-328, 2010[21] L. Bowtell, A.Ahfock, “Direct current offset controller for transformerless single phase photovoltaic grid inverters” , IET Renewable Power Generation Journal, Vol. 4, No. 5, pp 428-437, 2010 [22] Hao Zhou,Chawan Tong,Meiqin Mao,Chan Gao, “Development of single phase photovoltaic grid connected inverter based on DSP control” 2nd International Symposium on power electronics for distributed generation system, pg.no.650-653, 2010. [23] Bo Yang,Wuhua Li,Yi Zao,Xiangning He, “Design & analysis of grid connected photovoltaic system” IEEE transaction on power electronics,vol.25,no.4, pg.992-1000 April 2010. [24] Zhilei Yao,Lan Xio,Yanggang Yan, “Seamless Transfer of single phase grid interactive inverters between grid connected & stand alone modes” IEEE transaction on power electronics,vol. 25,No. 6, pg.1597-1603, June2010 . [25] Wang Song, Zhong Xiaoli, Yang Dongxuon, Lian Xiaoqin, Hao Ahihong, “Design of photovoltaic inverter system based on TMS320F28027” International Conference on computer application and system modeling, ICCASM 2010, V2-43 – V2-47, , Nov’2010 .

04/11/2023 ICAER 2013 67

References[26] J.Guerrero Perez, A. Molina Garcia, J.A.Villarejo,J.A.Feuntas, F.Ruz, “ Behavioral modeling and simulation of single phase grid connected photovoltaic inverters” IEEE conference on power and energy conference,pp 2351-2356,Nov 2010.[27] K.T.Tan, P.L.So, Y.C.Chu, K.H.Kwan, “Modeling, control and simulation of a photovoltaic power system for grid connected and standalone applications” , IEEE conference, IPEC 2010, pp 608-613, 2010.[28] M.Chael,E.Ropp & Sigifredo Gonzalez “Development of a MATLAB/simlink model of a single phase grid connected photovoltaic system” IEEE transaction on Energy conversion, vol 3, pp 344-349, 2009.[29] G. Carannante, Ciro Fraddanno, Mario Pagano, and Luigi Piegari, “Experimental Performance of MPPT Algorithm for Photovoltaic Sources Subject to Inhomogeneous Insolation” , IEEE Transaction on Industrial Electronics, Vol 56, No. 11, Nov’2009[30] Hiren Patel,Vivek Agarwal, “A single stage single phase transformerless doubly gronded grid connected PV interface”,IEEE transaction on Energy Conversion.Volume-24,no.1,March 2009.

04/11/2023 ICAER 2013 68

References• [31] Wang nianchun, Xu qingshan, Shibin, Kazato Yukita, “Research of single phase inverter for PV

modules with MPPT.” IEEE conference on power and energy conversion, pp 265-271, Nov 2009.• [32] G.Carannarte, Ciro Fraddanno, Mario Pagano, Luigi Peigari, “ Experimental Performance of

MPPT algorithm for photovoltaic sources subject to inhomogeneous insolations” , IEEE transaction on Industrial Electronics, Vol 56, No. 11, pp 4374-4380, Nov 2009.

•  [33] Julien Hobraiche, Jean-Paul Vilain, Patrice Macret, “ A new PWM strategy to reduce the inverter input current ripples” , IEEE transaction on Power Electronics, Vol 24, No. 1, pp 172-180, Jan 2009.

•  [34] Huan-Liang Tsei,Ci-Siang Tu,Yi-Jiesu, “Development of generalized photovoltaic model using MATLAB/simulink”,proceedings of the world congress on engineering & computer science,2008,WCECS, san Francisco,USA, Oct2008.

•  [35] D.Amorndecaphon & S.Prenurudeeppreechacharn, “An improved single phase inverter for small PV system using soft switching technique” , proceeding of ECTI-CON, 2008.

•  [36] Roberto Ganzalez, Jesus Lopez, Pablo Sanchis, Luis Marroyo, “ Transformerless inverter for single phase photovoltaic system” , IEEE transaction on Power Electronics, Vol 22, No. 2, 693-697, March 2007.

•  [37] Dezso Sera, Remus Teodorescu, Tamas Kerekes “Teaching Maximum Power Point Trackers Using a Photovoltaic Array Model with Graphical User Interface” Proceedings of International workshop, IWTPV2006, Czech Republic, March 2006

04/11/2023 ICAER 2013 69

References• [38] Tamás Kerekes, Dezső Séra, Remus Teodorescu “PV inverter control using a TMS320F2812 DSP”,

Proceedings of EDERS 2006, Munich, Germany, April 2006. • [39] Zainal Salam, Tohleong Soon, Mohd. Zulkifli Ramli, “ Hardware Implementation of high frequency

link inverter using dSPACE DS1104 digital signal processing board’ , First IEEE International Conference on Power and Energy Conference PECon, Malaysia, 348-352, Nov 2006.

•  [40] B.Ismail, S.Taib, A.R.Mohd Sood, M.Isa, C.M.Hadzer, “ Development of a single phase SPWM microcontroller based inverter” First IEEE conference on Power and Energy PECon, Malaysia Proceedings, pp 437-440, Nov 2006.

•  [41] Feel-Soon Kang,Sung-Jun Park,Chel-U Kim, “Multilevel PWM inverters suitable for the use of standalone photovoltaic power system” ,IEEE transaction on energy conversion,vol.20.no. 4,pg 906-915, Dec2005.

•  [42] Zhao Qinglin, Xu Yunhua, Jin Xiaoyi, Wu Weiyang, “DSP based closed loop control of bidirectional high frequency link inverter with active clamp”, IAS2005, IEEE proceedings, pp 928-933, 2005.

•  [43] Soeren Baekhoej Kjaer, John. K. Padersen, Frede Bloabjerg, “ A review of single phase grid – connected inverters for photovoltaic modules” , IEEE Transaction on Industry Application, Vol 41, NNo. 5, pp 1292-1306, Sept 2005.

•  [44] M. F. N. Tajuddin, N. H. Ghazali, I. Daut and B. Ismail, “using DSP technology for true sine PWM inverters”,27th International Spring Seminar on Electronics Echnology, IEEE, pg 141-146, 2004 .

•  [45] S.Yuvaranjan, Dachuan Yu, Shanguang Xu, “A novel power converter for photovoltaic application”, Journal for power sources, Elsevier, doi: 10.1016 / J. Jpowersou.2004.03.066, pp327-331, 2004.

04/11/2023 ICAER 2013 70

Thank You