Journal of Power Electronics

The Korean Institute of Power Electronics (전력전자학회)
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A simple closed-loop interphase power controller for cascaded H-bridge converter-based DG units in islanded microgrids with imbalanced loads

  • Baoxian Li (Department of Electrical Engineering, Tianjin University) ;
  • Yuanhui Chen (Department of Electrical Engineering, Tianjin University) ;
  • Jinwei He (Department of Electrical Engineering, Tianjin University)
  • Received : 2022.08.02
  • Accepted : 2023.05.30
  • Published : 2023.10.20
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Abstract

Cascaded H-bridge (CHB) converters have been used to integrate multiple DC sources into grids with only a single-stage power conversion. However, power sharing among parallel DG units and power sharing among power cells of a CHB converter must be satisfied when they are used in an islanded microgrid system. This work presents a comprehensive power sharing scheme. First, the power sharing between parallel DG units is realized using the well-understood droop control. Power allocation among the CHB converter three-phase legs is also obtained with injection of zero-sequence voltage. In contrast with the conventional open-loop zero-sequence voltage injection approaches, where the reference zero-sequence voltage is obtained via an open-loop interphase power adjustment manner that is typically calculated based on the assumption of a well-balanced three-phase converter current, the proposed approach obtains zero steady-state interphase power control errors via a simple closed-loop interphase power controller. This approach can be used in the case of a CHB system with significant imbalanced current presented. Finally, a power sharing approach among the series-connected H-bridge modules within a converter leg is also developed via the re-distribution of series-connected module voltages. Each power cell can actively participate in the power sharing according to the back-stage battery state of charges using the aforementioned approach, but without any interference from the abovementioned triple-layer power control architecture.

Keywords

Acknowledgement

This work was supported by Shenzhen Municipal Key Technical Research Project (No: JSGG20200914113601004).

References

  1. Townsend C D, Summers T J, Betz R E: Control and modulation scheme for a Cascaded H-Bridge multi-level converter in large scale photovoltaic systems. IEEE Energy Conversion Congress & Exposition, (2012)
  2. Cuzmar, R.H.: Pereda, J and Aguilera, RP Phase-shifted model predictive control to achieve power balance of CHB converters for large-scale photovoltaic integration. IEEE Trans. Indus. Electron. 68(10), 9619-9629 (2020) https://doi.org/10.1109/TIE.2020.3026299
  3. Sharma, R., Das, A.: Extended reactive power exchange with faulty cells in grid-tied cascaded H-bridge converter for solar photovoltaic application. IEEE Trans. Power Electron. 35(6), 5683-5691 (2019) https://doi.org/10.1109/TPEL.2019.2950336
  4. Sonti, V., Dhara, S., Kukade, P., Jain, S., Agarwal, V.: Analysis for the minimization of leakage and common mode currents in cascaded half-bridge PV fed multilevel inverter. IEEE J. Emerg. Sel. Top. Power Electron. 7(4), 2443-2452 (2018)
  5. Zhang, Q., Sun, K.: A flexible power control for PV-battery hybrid system using cascaded H-bridge converters. IEEE J. Emerg. Sel. Top. Power Electron. 7(4), 2184-2195 (2018) https://doi.org/10.1109/JESTPE.2018.2887002
  6. Mhiesan, H., Wei, Y., Siwakoti, Y.P., Mantooth, H.A.: A fault-tolerant hybrid cascaded H-bridge multilevel inverter. IEEE Trans. Power Electron. 35(12), 12702-12715 (2020) https://doi.org/10.1109/TPEL.2020.2996097
  7. Du, L., He, J.: A simple autonomous phase-shifting PWM approach for series-connected multi-converter harmonic mitigation. IEEE Trans. Power Electron. 34(12), 11516-11520 (2019) https://doi.org/10.1109/TPEL.2019.2919386
  8. Liu, C., Gao, N., Cai, X., Li, R.: Differentiation power control of modules in second-life battery energy storage system based on cascaded H-bridge converter. IEEE Trans. Power Electron. 35(6), 6609-6624 (2019) https://doi.org/10.1109/TPEL.2019.2954577
  9. Xu, B., Tu, H., Du, Y., Yu, H., Liang, H., Lukic, S.: A distributed control architecture for cascaded H-bridge converter with integrated battery energy storage. IEEE Trans. Indus. Appl. 57(1), 845-856 (2020) https://doi.org/10.1109/TIA.2020.3039430
  10. Liu, C., Cai, X., Chen, Q.: Self-adaptation control of second-life battery energy storage system based on cascaded H-bridge converter. IEEE J. Emerg. Sel. Top. Power Electron. 8(2), 1428-1441 (2018) https://doi.org/10.1109/JESTPE.2018.2886965
  11. Aguilera, R.P., Acuna, P., Yu, Y., Konstantinou, G., Townsend, C.D.: Predictive control of cascaded H-bridge converters under unbalanced power generation. IEEE Trans. Indus. Electron. 64(1), 4-13 (2016) https://doi.org/10.1109/TIE.2016.2605618
  12. Zhang, Q.: Control of PV battery hybrid system using Cascaded H Bridge converter. IEEE 3rd International Future Energy Electronics Conference and ECCE Asia, 2008-2012 (2017)
  13. Ota, J.I.Y., Shibano, Y., Akagi, H.: A phase-shifted PWM D-STATCOM using a modular multilevel cascade converter (SSBC)-Part II: Zero-voltage-ride-through capability. IEEE Trans. Ind. Appl. 51(1), 289-296 (2014)
  14. Yu, Y., Konstantinou, G., Hredzak, B. and Agelidis, V.G.: On extending the energy balancing limit of multilevel cascaded H-bridge converters for large-scale photovoltaic farms. Australasian Universities Power Engineering Conference, 1-6 (2013)
  15. Xiao, B., Hang, L., Mei, J., Riley, C., Tolbert, L.M., Ozpineci, B.: Modular cascaded H-bridge multilevel PV inverter with distributed MPPT for grid-connected applications. IEEE Trans. Ind. Appl. 51(2), 1722-1731 (2014)
  16. Yu, Y., Konstantinou, G., Townsend, C.D., Agelidis, V.G.: Comparison of zero-sequence injection methods in cascaded H-bridge multilevel converters for large-scale photovoltaic integration. IET Renew. Power Gener. 11(5), 603-613 (2017) https://doi.org/10.1049/iet-rpg.2016.0621
  17. Yu, Y., Konstantinou, G., Hredzak, B., Agelidis, V.G.: Power balance of cascaded H-bridge multilevel converters for large-scale photovoltaic integration. IEEE Trans. Power Electron. 31(1), 292-303 (2015) https://doi.org/10.1109/TPEL.2015.2406315
  18. Lu, D., Sha, C., Yu, Y., Li, X., Hu, H., Xing, Y.: Flexible nonsinusoidal zero-sequence voltage injection method to extend negative sequence current compensation range for star-connected CHB STATCOM. IEEE Trans. Power Electron. 36(10), 11357-11371 (2021) https://doi.org/10.1109/TPEL.2021.3071458
  19. Lu, D., Zhu, J., Wang, J., Yao, J., Wang, S., Hu, H.: A simple zero-sequence-voltage-based cluster voltage balancing control and the negative sequence current compensation region identification for star-connected cascaded H-bridge STATCOM. IEEE Trans. Power Electron. 33(10), 8376-8387 (2017)
  20. Mao, W., Zhang, X., Zhao, T., Hu, Y., Wang, F., Dai, Z., Cao, R.: Research on power equalization of three-phase cascaded h-bridge photovoltaic inverter based on the combination of hybrid modulation strategy and zero-sequence injection methods. IEEE Trans. Industr. Electron. 67(11), 9337-9347 (2019)
  21. Byrne, R.H., Nguyen, T.A., Copp, D.A., Chalamala, B.R., Gyuk, I.: Energy management and optimization methods for grid energy storage systems. IEEE Access 6(12), 13231-13260 (2018) https://doi.org/10.1109/ACCESS.2017.2741578
  22. Oriti, G., Julian, A.L., Peck, N.J.: Power-electronics-based energy management system with storage. IEEE Trans. Power Electron. 31(1), 452-460 (2016) https://doi.org/10.1109/TPEL.2015.2407693
  23. Maharjan, L., Yamagishi, T., Akagi, H.: Active-power control of individual converter cells for a battery energy storage system based on a multilevel cascade PWM converter. IEEE Trans. Power Electron. 27(3), 1099-1107 (2010)