A Low Leakage Current Quasi-Z-Source Photovoltaic Inverter for New Energy Mountain Agricultural Machinery
DOI:
https://doi.org/10.54097/anxd1w30Keywords:
Photovoltaic Power Generation, Grid-connected, Inverter, Leakage Current, Quasi-Z-source;, Mountain Agricultural Machinery, Dead-time-freeAbstract
The quasi-Z-source photovoltaic inverter offers advantages such as eliminating the need for dead-time, effectively suppressing high-frequency common-mode leakage current, eliminating the need for a bulky isolation transformer, and improving DC voltage utilization by inserting shoot-through vectors to boost the DC bus voltage. In contrast, traditional bridge-type grid-connected inverters suffer from drawbacks including the need for dead-time, large high-frequency common-mode leakage current, the requirement for a bulky isolation transformer, and low DC voltage utilization. To address these deficiencies, this paper first proposes a low-leakage-current quasi-Z-source photovoltaic inverter structure suitable for new energy agricultural machinery in mountainous areas. Next, the circuit topology and modulation strategy are presented, and the operating modes as well as the common-mode leakage current are analyzed. The research then shows that the proposed inverter not only eliminates the need for dead-time and effectively suppresses high-frequency common-mode leakage current, but also avoids the use of a bulky isolation transformer while effectively boosting the DC bus voltage and improving the DC voltage utilization of the grid-connected inverter. Finally, circuit simulation experiments verify the correctness of the inverter design and theoretical analysis.
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[1] Xiao, H. F., Wang, X. B., Zhang, X., et al. (2020). State-of-the-art and future trend of transformerless photovoltaic grid-connected inverters. Proceedings of the CSEE, 40(4), 1038–1054, 1397.
[2] Xiao, H. F., Xie, S. J., Chen, W. M., et al. (2010). Study on leakage current model for transformerless photovoltaic grid-connected inverter. Proceedings of the CSEE, 30(18), 9–14.
[3] Wu, W. Y., & Guo, X. Q. (2012). A review of novel leakage current suppression techniques for transformerless photovoltaic inverters. Proceedings of the CSEE, 32(18), 1–8, 170.
[4] Guo, X. Q., & Jia, X. Y. (2018). Analysis of common mode leakage current for transformerless cascaded H5 PV inverter. Transactions of China Electrotechnical Society, 33(2), 361–369.
[5] Wang, B. C., Guo, X. Q., Yang, Y., et al. (2018). Common mode behavior for Z-source four-leg inverter. Transactions of China Electrotechnical Society, 33(24), 5848–5855.
[6] Li, Y., & Peng, F. Z. (2011). Constant capacitor voltage control strategy for Z-source/quasi-Z-source inverter in grid-connected photovoltaic systems. Transactions of China Electrotechnical Society, 26(5), 62–69.
[7] Qu, A. W., Chen, D. L., & Su, Q. (2017). Novel single-stage three-phase voltage-fed quasi-z-source photovoltaic grid-connected inverter. Proceedings of the CSEE, 37(7), 2091–2101.
[8] Chen, Y., Huang, K., & Cao, Z. H. (2023). Third harmonic compensation strategy of quasi-Z-source cascaded multilevel photovoltaic grid-connected inverter. Power System Protection and Control, 51(9), 147–155.
[9] Zhang, Z. B., Zhang, X., Cao, R. X., et al. (2012). A new family of buck-boost grid-connected inverters. Proceedings of the CSEE, 32(27), 8–15, 185.
[10] Liu, F., Duan, S. X., Liu, B. Y., et al. (2007). A variable step size INC MPPT method for PV systems. Proceedings of the CSEE, 27(12), 50–55.
[11] Wang, B. C., Guo, X. Q., Yang, Y., et al. (2019). Common-mode voltage suppression strategy for Z-source four-leg inverter. Transactions of China Electrotechnical Society, 34(6), 1241–1249.
[12] Cheng, Q. M., Jiang, C., Shen, L., et al. (2020). Passivity-based control strategy of quasi Z-source three-level grid-connected inverter. Transactions of China Electrotechnical Society, 35(20), 4361–4372.
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