COMMON-GROUND FIVE-LEVEL PHOTOVOLTAIC INVERTER BASED ON SWITCHED-CAPACITOR

Wang Junpeng; Wang Xiaolin; Ye Yuanmao

doi:10.19912/j.0254-0096.tynxb.2022-0225

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Acta Energiae Solaris Sinica ›› 2023, Vol. 44 ›› Issue (6) : 234-241. DOI: 10.19912/j.0254-0096.tynxb.2022-0225

COMMON-GROUND FIVE-LEVEL PHOTOVOLTAIC INVERTER BASED ON SWITCHED-CAPACITOR

Wang Junpeng, Wang Xiaolin, Ye Yuanmao

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Abstract

In order to meet the requirements of voltage boosting and leakage current elimination in grid-connected photovoltaic inverters, a common-ground five-level inverter based on switched-capacitor （SC） is proposed in this paper. The proposed topology possesses the advantages of self-boosting voltage, less components, capacitor voltage self-balance and scalability etc. Meanwhile, the leakage current caused by the common mode voltage （CMV） is eliminated by the common-ground structure, thereby reducing the electromagnetic interference and power loss of the inverter, and improving the safety of the system. Then, a hybrid modulation strategy with phase-shifted carriers is adopted to prevent the switched-capacitor from continuously discharging, which not only reduces the voltage ripple of the switched-capacitor, but also improves the quality of SPWM output voltage waveform. Furthermore, the advantages of the proposed topology have been demonstrated by comparing with other five-level topologies in terms of the circuit structure, voltage-boosting capability and reducing capacitor voltage. Finally, the feasibility of the proposed inrerter and the effectiveness of the hybrid modulation strategy are verified experimentally. The results show that the proposed inverter has better static and dynamic characteristics as well as higher conversion efficiency.

Key words

photovoltaic / inverter / switched-capacitor / multilevel / common-ground

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Wang Junpeng, Wang Xiaolin, Ye Yuanmao. COMMON-GROUND FIVE-LEVEL PHOTOVOLTAIC INVERTER BASED ON SWITCHED-CAPACITOR[J]. Acta Energiae Solaris Sinica. 2023, 44(6): 234-241 https://doi.org/10.19912/j.0254-0096.tynxb.2022-0225

References

[1] 郭苏, 何意, 蒋川, 等. 风电-光伏-储热联合发电系统的多目标容量优化[J]. 太阳能学报, 2020, 41(11): 359-368.
GUO S, HE Y, JIANG C, et al.Capacity optimization of wind-photovoltaic-thermal energy storage-electric heater hybrid power system[J]. Acta energiae solaris sinica, 2020, 41(11): 359-368.
[2] 李君, 朱家玲, 崔志伟, 等. 太阳能与地热能耦合发电系统性能研究[J]. 太阳能学报, 2018, 39(11): 2997-3004.
LI J, ZHU J J, CUI Z W, et al.Themodynamics analysis of a hybrid solar-geothermal power generation system[J]. Acta energiae solaris sinica, 2018, 39(11): 2997-3004.
[3] 卢斯煜, 周保荣, 饶宏, 等. 高比例光伏发电并网条件下中国远景电源结构探讨[J]. 中国电机工程学报, 2018,38(S1): 39-44.
LU S Y, ZHOU B R, RAO H, et al.Research of the prospect of China power generation structure with high proportion of photovoltaic generation[J]. Proceedings of the CSEE, 2018, 38(S1): 39-44.
[4] CHEN M J, AFRIDI K K, PERREAULT D J.A multilevel energy buffer and voltage modulator for grid-interfaced microinverters[J]. IEEE transactions on power electronics, 2015, 30(3): 1203-1219.
[5] LORENZANI E, CONCARI C, BARATER D, et al.Recent advances in single-phase transformerless photovoltaic inverters[J]. IET renewable power generation, 2016, 10(2): 260-273.
[6] 肖华锋, 王晓标, 张兴, 等. 非隔离光伏并网逆变技术的现状与展望[J]. 中国电机工程学报, 2020, 40(4):1038-1054, 1397.
XIAO H F, WANG X B, ZHANG X, et al.State-of-the-art and future trend of transformerless photovoltaic grid-connected inverters[J]. Proceedings of the CSEE, 2020, 40(4): 1038-1054,1397.
[7] 张兴, 孙龙林, 许颇, 等. 单相非隔离型光伏并网系统中共模电流抑制的研究[J]. 太阳能学报, 2009, 30(9):1202-1208.
ZHANG X, SUN L L, XU P, et al.Research on common-mode current reduction of nonisolated single-phase grid-connected photovoltaic systems[J]. Acta energiae solaris sinica, 2009, 30(9): 1202-1208.
[8] LOPEZ O, TEODORESCU R, FREIJEDO F, et al.Eliminating ground current in a transformerless photo-voltaic application[C]//IEEE Power Engineering Society General Meeting, Tampa, FL, USA, 2007.
[9] GONZALEZ R, LOPEZ J, SANCHIS P, et al.Transformerless inverter for single-phase photovoltaic systems[J]. IEEE transactions on power electronics, 2007, 22(2): 693-697.
[10] LI W H, GU Y J, LUO H Z, et al.Topology review and derivation methodology of single-phase transformerless photovoltaic inverters for leakage current suppression[J]. IEEE transactions on industrial electronics, 2015, 62(7): 4537-4551.
[11] XIAO H F, XIE S J.Leakage current analytical model and application in single-phase transformerless photovoltaic grid-connected inverter[J]. IEEE transactions on electromagnetic compatibility, 2010, 52(4): 902-913.
[12] VICTOR M, GREIZER F, BREMICKER S, et al. Method of converting a direct current voltage from a source of direct current voltage, more specifically from a photo-voltaic source of direct current voltage, into an alternating current voltage: US7411802[P].2008-8-12.
[13] ZHANG L, SUN K, XING Y, et al.H6 transformerless full-bridge PV grid-tied inverters[J]. IEEE transactions on power electronics, 2014, 29(3): 1229-1238.
[14] YANG B, LI W H, GU Y J, et al.Improved transformerless inverter with common-mode leakage current elimination for a photovoltaic grid-connected power system[J]. IEEE transactions on power electronics, 2012, 27(2): 752-762.
[15] GU B, DOMINIC J, LAI J S, et al.High reliability and efficiency single-phase transformerless inverter for grid-connected photovoltaic systems[J]. IEEE transactions on power electronics, 2013, 28(5): 2235-2245.
[16] GONZALEZ R, GUBIA E, LOPEZ J, et al.Transformerless single-phase multilevel-based photo-voltaic inverter[J]. IEEE transactions on industrial electronics, 2008, 55(7): 2694-2702.
[17] XIAO H F, XIE S J.Transformerless split-inductor neutral point clamped three-level PV grid-connected inverter[J]. IEEE transactions on power electronics, 2012, 27(4): 1799-1808.
[18] VAZQUEZ N, ROSAS M, HERNANDEZ C, et al.A new common-mode transformerless photovoltaic inverter[J]. IEEE transactions on industrial electronics, 2015, 62(10): 6381-6391.
[19] 王众, 姚志垒, 王勤, 等. 宽电压输入双接地单相非隔离光伏并网逆变器[J]. 中国电机工程学报, 2020, 40(3): 911-920.
WANG Z, YAO Z L, WANG Q, et al.Single-phase double-grounded transformerless PV grid-connected inverter with wide input voltage range[J]. Proceedings of the CSEE, 2020, 40(3): 911-920.
[20] 曾正, 赵荣祥, 汤胜清, 等. 可再生能源分散接入用先进并网逆变器研究综述[J]. 中国电机工程学报, 2013,33(24): 1-12,21.
ZENG Z, ZHAO R X, TANG S Q, et al.An overview on advanced grid-connected inverters used for decentralized renewable energy resources[J]. Proceedings of the CSEE,2013, 33(24): 1-12,21.
[21] WANG H L, KOU L, LI Y F, et al.A new six-switch five-level active neutral point clamped inverter for PV applications[J]. IEEE transactions on power electronics, 2017, 32(9): 6700-6715.
[22] SIWAKOTI Y P, PALANISAMY A, MAHAJAN A, et al.Analysis and design of a novel six-switch five-level active boost neutral point clamped inverter[J]. IEEE transactions on industrial electronics, 2020, 67(12): 10485-10496.
[23] SHAFFER B, HASSAN H A, SCOTT M J, et al.A common-ground single-phase five-level transformerless boost inverter for photovoltaic applications[C]//IEEE Applied Power Electronics Conference and Exposition, San Antonio, TX, USA, 2018.
[24] 廖志凌, 张豪, 陈兆岭. 共地型五电平单相非隔离光伏并网逆变器[J]. 中国电机工程学报, 2021, 41(14): 4984-4993.
LIAO Z L, ZHANG H, CHEN Z L.Common-ground-type five-level single-phase transformerless PV grid-connected inverters[J]. Proceedings of the CSEE, 2021, 41(14): 4984-4993.
[25] GRIGOLETTO F B.Multilevel common-ground transformerless inverter for photovoltaic applications[J]. IEEE journal of emerging and selected topics in power electronics, 2021, 9(1): 831-842.