Photovoltaic Grid-connected Power System with Common Mode Leakage Current Elimination using an Improvised Transformer less Inverter

Authors

  • Mohammed Safique  Department of Electrical Engineering, Anjuman College of Engineering and Technology, Sadar, Nagpur, Maharashtra, India
  • Dr. Harikumar Naidu  Department of Electrical Engineering, T.G.P. College of Engineering & Technology, Nagpur Maharashtra, India

Keywords:

Common-Mode Leakage Current, Junction Capacitance, Phase Shift, Photovoltaic (PV) System, Sinusoidal Pulse Width Modulation (SPWM) Strategy, Transformer Less Inverter.

Abstract

To remove the common-mode leakage current in the transformer less photovoltaic grid-connected system, an improved single-phase inverter topology is presented. The improved transformer less inverter can use the same low input voltage as the full-bridge inverter and guarantee to completely meet the condition of eliminating common-mode leakage current. Both the unipolar sinusoidal pulse width modulation (SPWM) along with the double frequency SPWM control strategy can be used to implement the three-level output in the presented scheme. The high efficiency and convenient thermal design are achieved due to the decoupling of two extra switches connected to the dc side. Moreover, the higher frequency and lower current ripples are achieved by using the double-frequency SPWM, and thus the total harmonic distortion of the grid-connected current are minimised. Furthermore, the effect of the phase shift between the output voltage and current, and the influence of the junction capacitances of the power switches are studied in detail. Simulation for unipolar and bipolar SPWM are being carried out to validate the result.

References

  1. B. Kjaer, J. K. Pedersen, and F. Blaabjerg, "A review of single-phase grid-connected inverters for photovoltaic modules," IEEE Trans. Ind. Appl., vol. 41, no. 5, pp. 1292–1306, Sep./Oct. 2005.
  2. Li and P.Wolfs, "A review of the single phase photovoltaic module integrated converter topologies with three different DC link configurations," IEEE Trans. Power Electron., vol. 23, no. 3, pp. 1320–1333, May 2008.
  3. Calais, J.Myrzik, T. Spooner, and V. G. Agelidis, "Inverters for singlephase grid connected photovoltaic systems: An overview," in Proc. IEEE 33rd Annu. Power Electron. Spec. Conf., 2002, vol. 4, pp. 1995–2000.
  4. Yao, L. Xiao, and Y. Yan, "Seamless transfer of single-phase gridinteractive inverters between grid-connected and stand-alone modes," IEEE Trans. Power Electron., vol. 25, no. 6, pp. 1597–1603, Jun. 2010.
  5. Yang, W. Li, Y. Zhao, and X. He, "Design and analysis of a gridconnected photovoltaic power system," IEEE Trans. Power Electron., vol. 25, no. 4, pp. 992–1000, Apr. 2010.
  6. M. A. Myrzik and M. Calais, "String and module integrated inverters for single-phase grid connected photovoltaic systems: A review," in IEEE Bologna Power Tech. Conf. Proc., Jun. 2003, vol. 2, p. 8.
  7. Kerekes, R. Teodorescu, and U. Borup, "Transformerless photovoltaic inverters connected to thegrid," in Proc. IEEE 22nd Annu. Appl. Power Electron. Conf., 2007, pp. 1733–1737.
  8. Lopez, R. Teodorescu, and J. Doval-Gandoy, "Multilevel transformerless topologies for single-phase grid-connected converters," in Proc. 32nd Annu. Conf. IEEE Ind. Electron. Soc., Nov. 2006, pp. 5191–5196.
  9. Gonzalez, E. Gubia, J. Lopez, and L.Marroyo, "Transformerless singlephase multilevel-based photovoltaic inverter," IEEE Trans. Ind. Electron., vol. 55, no. 7, pp. 2694–2702, Jul. 2008.
  10. Lopez, F. D. Freijedo, A. G. Yepes, P. Fernandez-Comesaa, J. Malvar, R. Teodorescu, and J. Doval-Gandoy, "Eliminating ground current in a transformerless photovoltaic application," IEEE Trans. Energy Convers., vol. 25, no. 1, pp. 140–147, Mar. 2010.
  11. M. Hava and E. Un, "Performance analysis of reduced common-mode voltage PWM methods and comparison with standard PWM methods for three-phase voltage-source inverters," IEEE Trans. Power Electron., vol. 24, no. 1, pp. 241–252, Jan. 2009.
  12. Xiao and S. Xie, "Leakage current analytical model and application in single-phase transformerless photovoltaic grid-connected inverter," IEEE Trans. Electromagn. Compat., vol. 52, no. 4, pp. 902–913, Nov. 2010.
  13. Kerekes, M. Liserre, R. Teodorescu, C. Klumpner, and M. Sumner, "Evaluation of three-phase transformerless photovoltaic inverter topologies," IEEE Trans. Power Electron., vol. 24, no. 9, pp. 2202–2211, Sep. 2009.
  14. Kerekes, R. Teodorescu, and M. Liserre, "Common mode voltage in case of transformerless PV inverters connected to the grid," in Proc. IEEE Int. Symp. Ind. Electron., Jun./Jul. 2008, pp. 2390–2395.
  15. Vazquez, T. Kerekes, A. Rolan, D. Aguilar, A. Luna, and G. Azevedo, "Losses and CMV evaluation in transformerless grid-connected PV topologies," in Proc. IEEE Int. Symp. Ind. Electron., Jul. 2009, pp. 544– 548.
  16. C. Cavalcanti, K. C. de Oliveira, A. M. de Farias, F. A. S. Neves, G. M. S. Azevedo, and F. C. Camboim, "Modulation techniques to eliminate leakage currents in transformerless three-phase photovoltaic systems," IEEE Trans. Ind. Electron., vol. 57, no. 4, pp. 1360–1368, Apr.2010.
  17. Victor, F. Greizer, S. Bremicker, and U. Hubler, "Method of converting a direct current voltage from a source of direct current voltage, more specifically from a photovoltaic couse of direct current voltage, into a alternating current voltage," DE Patent DE102004030912 (B3), Jan. 1,2006.
  18. Schmidt, S. Christoph, and J. Ketterer, "Current inverter for direct/ alternating currents, has direct and alternating connections with an intermediate power store, a bridge circuit, rectifier diodes and a inductive choke," DE Patent DE10221592 (A1), Dec. 04, 2003.
  19. Gonzalez, J. Lopez, P. Sanchis, and L. Marroyo, "Transformerless inverter for single-phase photovoltaic systems," IEEE Trans. Power Electron., vol. 22, no. 2, pp. 693–697, Mar. 2007.
  20. Yu, Jih-Sheng Lai, H. Qian, C. Hutchens, J. Zhang, G. Lisi, A. Djabbari, G. Smith, and T. Hegarty, "High-efficiency inverter with H6-type configuration for photovoltaic non-isolated AC module applications," in Proc. IEEE 25th Annu. Appl. Power Electron. Conf. Expo., Feb. 2010, pp. 1056–1061.
  21. Kasa, T. Iida, and H. Iwamoto, "An inverter using buck-boost type chopper circuits for popular small-scale photovoltaic power system," in Proc. 25th Annu. Conf. IEEE Ind. Electron. Soc., 1999, vol. 1, pp. 185– 190.
  22. Karschny, "Wechselrichter," Patent DE19642522 (C1), Apr. 23, 1998.
  23. V. Araujo, P. Zacharias, and R. Mallwitz, "Highly efficient single-phase transformerless inverters for grid-connected photovoltaic systems," IEEE Trans. Ind. Electron., vol. 57, no. 9, pp. 3118–3128, Sep. 2010.
  24. Gonzalez, J. Lopez, P. Sanchis, E. Gubia, A. Ursua, and L. Marroyo, "High-efficiency transformerless single-phase photovoltaic inverter," in Proc. 12th Int. Power Electron. Motion Control Conf., Aug./Sep. 2006, pp. 1895–1900.
  25. Burger and D. Kranzer, "Extreme high efficiency PV-power converters," in Proc. 13th Eur. Conf. Power Electron. Appl., Sep. 2009, pp. 1–13.

International Journal of Scientific Research in Science and Technology

Downloads

Published

2016-12-30

Issue

Volume 2, Issue 6 , November-December-2016

Section

Research Articles

License

Copyright (c) IJSRST

Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 International License.

How to Cite

[1]
Mohammed Safique, Dr. Harikumar Naidu, " Photovoltaic Grid-connected Power System with Common Mode Leakage Current Elimination using an Improvised Transformer less Inverter, International Journal of Scientific Research in Science and Technology(IJSRST), Online ISSN : 2395-602X, Print ISSN : 2395-6011, Volume 2, Issue 6 , pp.332-339, November-December-2016.