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A New Photovoltaic System Architecture of Module-Integrated Converter with a Single-sourced Asymmetric Multilevel Inverter Using a Cost-effective Single-ended Pre-regulator

  • Received : 2016.05.13
  • Accepted : 2016.09.20
  • Published : 2017.01.20

Abstract

In this paper, a new architecture for a cost-effective power conditioning systems (PCS) using a single-sourced asymmetric cascaded H-bridge multilevel inverter (MLI) for photovoltaic (PV) applications is proposed. The asymmetric MLI topology has a reduced number of parts compared to the symmetrical type for the same number of voltage level. However, the modulation index threshold related to the drop in the number of levels of the inverter output is higher than that of the symmetrical MLI. This problem results in a modulation index limitation which is relatively higher than that of the symmetrical MLI. Hence, an extra voltage pre-regulator becomes a necessary component in the PCS under a wide operating bias variation. In addition to pre-stage voltage regulation for the constant MLI dc-links, another auxiliary pre-regulator should provide isolation and voltage balance among the multiple H-bridge cells in the asymmetrical MLI as well as the symmetrical ones. The proposed PCS uses a single-ended DC-DC converter topology with a coupled inductor and charge-pump circuit to satisfy all of the aforementioned requirements. Since the proposed integrated-type voltage pre-regulator circuit uses only a single MOSFET switch and a single magnetic component, the size and cost of the PCS is an optimal trade-off. In addition, the voltage balance between the separate H-bridge cells is automatically maintained by the number of turns in the coupled inductor transformer regardless of the duty cycle, which eliminates the need for an extra voltage regulator for the auxiliary H-bridge in MLIs. The voltage balance is also maintained under the discontinuous conduction mode (DCM). Thus, the PCS is also operational during light load conditions. The proposed architecture can apply the module-integrated converter (MIC) concept to perform distributed MPPT. The proposed architecture is analyzed and verified for a 7-level asymmetric MLI, using simulation results and a hardware implementation.

Acknowledgement

Supported by : KETEP

References

  1. S. Kouro, M. Malinowski, K. Gopakumar, J. Pou, L. G. Franquelo, B. Wu, J. Rodriguez, M. A. Perez, and J. I. Leon, "Recent advances and industrial applications of multilevel converters," IEEE. Trans. Ind. Electron., Vol. 57, No. 8, pp. 2553-2580, Aug. 2010. https://doi.org/10.1109/TIE.2010.2049719
  2. B. Xiao, L. Hang, J. Mei, C. Riley, L. M. Tolbert, and B. Ozpineci, "Modular cascaded H-bridge multilevel PV inverter with distributed MPPT for grid-connected applications," IEEE. Trans. Ind. Appl., Vol. 51, No. 2, pp. 1722-1731, Mar./Apr. 2015. https://doi.org/10.1109/TIA.2014.2354396
  3. H. R. Teymour, D. Sutanto, K. M. Muttaqi, and P. Ciufo, "Solar PV and battery storage integration using a new configuration of a three-level NPC inverter with advanced control strategy," IEEE. Trans. Energy Convers., Vol. 29, No. 2, pp. 354-365, Jun. 2014. https://doi.org/10.1109/TEC.2014.2309698
  4. M. Hamzeh, A. Ghazanfari, H. Mokhtari, and H. Karimi, "Integrating hybrid power source into an islanded MVMicrogrid using CHB multilevel inverter under unbalanced and nonlinear load conditions," IEEE Trans. Energy Convers., Vol. 28, No. 3, pp. 643-651, Sep. 2013. https://doi.org/10.1109/TEC.2013.2267171
  5. F.-S. Kang, S.-J. Park, S E. Cho, C. U. Kim, and T. Ise, "Multilevel PWM inverters suitable for the use of standalone photovoltaic power systems," IEEE Trans. Energy Convers., Vol. 20, No. 4, pp. 906-915, Dec. 2005. https://doi.org/10.1109/TEC.2005.847956
  6. S. Daher, J. Schmid, and F. L. M. Antunes, "Multilevel inverter topologies for stand-alone PV systems," IEEE Trans. Ind. Electron., Vol. 55, No. 7, pp. 2703-2712, Jul. 2008. https://doi.org/10.1109/TIE.2008.922601
  7. Y.-H. Liao and C.-M. Lai, "Newly-constructed simplified single-phase multistring multilevel inverter topology for distributed energy resources," IEEE. Trans. Power Electron., Vol. 26, No. 9, pp. 2386-2392, Sep. 2011. https://doi.org/10.1109/TPEL.2011.2157526
  8. M. Hamzeh, A. Ghazanfari, H. Mokhtari, and H. Karimi, "Integrating hybrid power source into an islanded MVMicrogrid using CHB multilevel inverter under unbalanced and nonlinear load conditions," IEEE Trans. Energy Convers., Vol. 28, No. 3, pp. 643-651, Sep. 2013. https://doi.org/10.1109/TEC.2013.2267171
  9. B. Xiao, L. Hang, J. Mei, C. Riley, L. M. Tolbert, and B. Ozpineci, "Modular cascaded H-bridge multilevel PV inverter with distributed MPPT for grid-connected applications," IEEE. Trans. Ind. Appl., Vol. 51, No. 2, pp. 1722-1731, Mar./Apr. 2015. https://doi.org/10.1109/TIA.2014.2354396
  10. E. Villanueva, P. Correa, J. Rodriguez, and M. Pacas, "Control of a single-phase cascaded H-bridge multilevel inverter for grid-connected photovoltaic systems," IEEE Trans. Ind. Electron., Vol. 56. No. 11. Pp. 4399-4406, Nov. 2009. https://doi.org/10.1109/TIE.2009.2029579
  11. S. K. Chattopadhay, C. Chakraborty, A. K. Sinha, and B. C. Pal, "Asymmetric multilevel inverter with quasi-linear power distribution ratio for grid connected photovoltaic converters," in IEEE International Symposium on Industrial Electronics (ISIE), pp. 1-6, May 2013.
  12. P. Barriuso, J. Dixon, P. Flores, and L. Moran, "Faulttolerant reconfiguration system for asymmetric multilevel converters using bidirectional power switches," IEEE Trans. Ind. Electron., Vol. 56, No. 4, pp. 1300-1306, Apr. 2009. https://doi.org/10.1109/TIE.2008.2005680
  13. S. G. Song, F. S. Kang, and S.-J. Park, "Cascaded multilevel inverter-employing three-phase transformers and single DC input," IEEE Trans. Ind. Electron., Vol. 56, No. 6, pp. 2005-2014, Jun. 2009. https://doi.org/10.1109/TIE.2009.2013846
  14. P. Flores, J. Dixon, M. Ortuzar, R. Carmi, P. Barriuso, and L. Moran, "Static var compensator and active power filter with power injection capability, using 27-level inverters and photovoltaic cells," IEEE Trans. Ind. Electron., Vol. 56, No. 1, pp. 130-138, Jan. 2009. https://doi.org/10.1109/TIE.2008.927229
  15. J. Dixon, J. Pereda, C. Castillo, and S. Bosch, "Asymmetrical multilevel inverter for traction drives using only one DC supply," IEEE Trans. Veh. Technol., Vol. 59. No. 8. Pp. 3736-3743, Oct. 2010. https://doi.org/10.1109/TVT.2010.2057268
  16. W.-Y. Choi and J.-Y. Choi, "High-efficiency power conditioning system for grid-connected photovoltaic modules," Journal of Power Electronics, Vol. 11, No. 4, pp. 561-567, Jul. 2011. https://doi.org/10.6113/JPE.2011.11.4.561
  17. J.-H. Park and B.-H. Cho, "Nonisolation soft-switching buck converter with tapped-inductor for wide-input extreme step-down applications," IEEE Trans. Circuits Syst. I, Reg. Papers, Vol. 54, No. 8, pp. 1809-1818, Aug. 2007, https://doi.org/10.1109/TCSI.2007.902482
  18. Y.-P. Hsieh, J.-F. Chen, T.-J. P. Liang, and L. S. Yang, "Novel high step-up DC-DC converter with coupledinductor and switched-capacitor techniques for a sustainable energy system," IEEE Trans. Power Electron., Vol. 26, No. 12, pp. 3481-3490, Dec. 2011. https://doi.org/10.1109/TPEL.2011.2160876
  19. K. C. Tseng, C. C. Huang, and W. Y. Shih, "A high step-up converter with a voltage multiplier module for a photovoltaic system," IEEE Trans. Power Electron., Vol. 28, No. 6, pp. 3047-3057, Jun. 2013. https://doi.org/10.1109/TPEL.2012.2217157
  20. B. Gu, J. Dominic, J.-S. Lai, Z. Zhao, and C. Liu, "High boost ratio hybrid transformer DC-DC converter for photovoltaic module applications," IEEE Trans. Power Electron., Vol. 28, No. 4, pp. 2048 -2058, Apr. 2013. https://doi.org/10.1109/TPEL.2012.2198834
  21. J.-H. Lee, J.-H. Park, and J. H. Jeon, "Series-connected forward-flyback converter for high step-up power conversion," IEEE Trans. Power Electron., Vol. 26, No. 12, pp. 3629-3641, Dec. 2011. https://doi.org/10.1109/TPEL.2011.2162747
  22. D.-H. Kim and J.-H. Park, "High efficiency step-down flyback converter using coaxial cable coupled-inductor," Journal of Power Electronics, Vol. 13, No. 2. pp. 214-222, Mar. 2013. https://doi.org/10.6113/JPE.2013.13.2.214
  23. S.-J. Park, J.-H. Shin, J.-H. Park, and H.-J. Jeon, "Dynamic analysis and controller design for standalone operation of photovoltaic power conditioners with energy storage," Journal of Electrical Engineering & Technology, Vol. 9, No. 6, pp. 2004-2012, Nov. 2014. https://doi.org/10.5370/JEET.2014.9.6.2004
  24. M. S. Manoharan, A. Ahmed, C.-G. Lee, and J.-H. Park, "Low cost single-sourced asymmetrical cascaded H-bridge multilevel inverter," in KIPE Power Electronics Annual Conference, pp. 323-324, Jul. 2015.
  25. D.-H. Kim, J.-H. Jang, J.-W. Kim, and J.-H. Park, "Singleended high-efficiency step-up converter using the isolated switched-capacitor cell," Journal of Power Electronics, Vol. 13, No. 5, pp. 766-778, Sep. 2013. https://doi.org/10.6113/JPE.2013.13.5.766
  26. B. P. McGrath, D. G. Holmes, M. Manjrekar, and T. A. Lipo, "An improved modulation strategy for a hybrid multilevel inverter," in IEEE Industry Applications Conference, pp. 2086-2093, Oct. 2000.
  27. M. A. Khlifi, "Study and control of photovoltaic water pumping system," Journal of Electrical Engineering & Technology, Vol. 11, No. 1, pp. 117-124, Jan. 2016. https://doi.org/10.5370/JEET.2016.11.1.117
  28. M. S. Manoharan, A. Ahmed, and J.-H. Park, "Peak-valley current mode controlled H-bridge inverter with digital slope compensation for cycle-by-cycle current regulation," Journal of Electrical Engineering & Technology, Vol. 10, No. 5, pp. 709-718, Oct. 2015. https://doi.org/10.5370/JEET.2015.10.3.709
  29. M. S. Manoharan, A. Ahmed, H. W. Kim, and J.-H. Park, "A single-source photovoltaic power conditioning system using asymmetric cascaded multilevel inverter," in 9th International Conference on Power Electronics and ECCE Asia (ICPE-ECCE Asia), Jun. 2015.
  30. N. A. Rahim and J. Selvaraj, "Multistring five-level inverter with novel PWM control scheme for PV application," IEEE Trans. Ind. Electron., Vol. 57, No. 6, pp. 2111-2123, Jun. 2010. https://doi.org/10.1109/TIE.2009.2034683

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