非隔离型低压柔性潮流转供装置共模电流直接闭环抑制策略

doi:10.19595/j.cnki.1000-6753.tces.231988

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Abstract With the continuous improvement of the penetration rate of distributed new energy power generation in distribution grids, there are a series of problems such as disordered distribution of current, reverse heavy overload of lines, and increased voltage fluctuations, which seriously affect the stability and safety of distributed new energy power generation and distribution grids. The flexible power flow controller has the excellent characteristics of two-way controllable energy and continuous current adjustment. In addition, it also has auxiliary functions such as direct access to distributed energy storage and active power quality adjustment.
Since the pulse width modulation (PWM) technology used in the converter will cause common-mode voltage (CMV). The CMVwill cause adversely affect to the system innon-isolation transformer. The common-mode current (CMC) will produce in the common-mode loop which make the harmonic distortion rate on the AC side increase and protection act incorrectly, and affect the normal operation of the system.
In order to solve this problem, a closed-loop suppression strategy for specified harmonics of CMC based on direct modulation of average common-mode voltage (AVE CMV) was proposed. An accurate common-mode circuit modelof non-isolated low-voltage flexible power flow controller was established to analyze the impedance characteristics and the dominant characteristics of CMC. The mathematical relationship between the AVE CMV and the CMC in a switching cycle was constructed and the correlation between the AVE CMV and the CMC during a switching cycle was revealed. Then, the precise adjustment of AVE CMV was realized through the coordinated distribution of the two-sided converter's zero vector, and then an efficient decoupling method of direct regulation of the AVE CMV and space vector pulse width modulation was proposed, which realized the closed-loop suppression of the specified CMC without affecting the dynamic regulation of the differential-mode current. Finally, the feasibility and effectiveness of this method were verified through experiments.
The following conclusions can be draw from the analysis: (1) The connection between the AVE CMV of a switching cycle and the CMC is revealed, and the limitations of the traditional common-mode voltage peak suppression method on the CMC suppression are pointed out. (2) It is clarified that the third and ninth harmonic components of the AVE CMV are the main cause of CMC.ACMC efficient suppression strategy based on closed-loop regulation of the third and ninth CMC is proposed.It is pointed out that the adjustment of the AVE CMV in a switching cycle can be achieved by adjusting the action time of the zero vector, and then the suppression of the overall CMC can be achieved by coordinated control of the action time of the different zero vectors of the two converters. (3) The proposed CMC suppression strategy and the highly decoupled characteristics of differential-mode current and power regulation in the system are analyzed and verified.The transient CMC suppression in the dynamic adjustment process of power and AC and DC voltage is realized.The method proposed can be applied to not only a two-port non-isolated flexible power flow controller, but also a multi-port flexible power flowcontroller through the AVE CMV synergy of the switching cycle between the ports.

Key words： Average common-mode voltage (AVE CMV) common mode current (CMC) suppression common mode loop third harmonic zero vector

Received: 27 November 2023

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	Cao Xiaojun
	He Jinwei
	Qiao Xuebo
	Han Junfei
	Wang Chengshan

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Cao Xiaojun,He Jinwei,Qiao Xuebo等. Direct Common-Mode Current Closed-Loop Suppression Strategy for Non-Isolated Low-Voltage Flexible Power Flow Controller[J]. Transactions of China Electrotechnical Society, 2025, 40(1): 152-163.

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[1] 张尧翔, 刘文颖, 庞清仑, 等. 高比例风电接入系统光热发电-火电旋转备用优化方法[J]. 电工技术学报, 2022, 37(21): 5478-5489.
Zhang Yaoxiang, Liu Wenying, Pang Qinglun, et al.Optimal power spinning reserve method of concentrating solar power and thermal power for high-proportion wind power system[J]. Transactions of China Electrotechnical Society, 2022, 37(21): 5478-5489.
[2] 颜湘武, 郭燕, 彭维锋, 等. 基于旋转移相变压器的电压源型无功补偿器及其控制策略[J]. 电工技术学报, 2023, 38(16): 4448-4464.
Yan Xiangwu, Guo Yan, Peng Weifeng, et al.Voltage source var compensator based on rotary phase shifting transformer and its control strategy[J]. Transactions of China Electrotechnical Society, 2023, 38(16): 4448-4464.
[3] 王成山, 季节, 冀浩然, 等. 配电系统智能软开关技术及应用[J]. 电力系统自动化, 2022, 46(4): 1-14.
Wang Chengshan, Ji Jie, Ji Haoran, et al.Technologies and application of soft open points in distribution networks[J]. Automation of Electric Power Systems, 2022, 46(4): 1-14.
[4] 徐玉韬, 冯起辉, 谈竹奎, 等. 考虑转供与重构协同的多端柔性互联配电网供电恢复策略[J]. 电工技术学报, 2024, 39(9): 2696-2709.
Xu Yutao, Feng Qihui, Tan Zhukui, et al.Optimal power restoration strategy for multi-terminal flexible interconnected distribution networks based on flexible interconnection device and network reconfiguration[J]. Transactions of China Electrotechnical Society, 2024, 39(9): 2696-2709.
[5] 周剑桥, 张建文, 席东民, 等. 基于SOP有功-无功协同的低压配电网末端电压越限治理[J]. 电力系统自动化, 2023, 47(6): 110-122.
Zhou Jianqiao, Zhang Jianwen, Xi Dongmin, et al.Terminal voltage overlimit mitigation for low-voltage distribution network based on coordinated active and reactive power control of soft open point[J]. Automation of Electric Power Systems, 2023, 47(6): 110-122.
[6] 沙广林, 刘斌, 邬玮晗, 等. 多端柔性互联的交直流配电系统分层控制策略[J]. 高电压技术, 2020, 46(10): 3509-3520.
Sha Guanglin, Liu Bin, Wu Weihan, et al.Hierarchical control strategy for multi-terminal flexible inter-connected AC/DC power distribution systems[J]. High Voltage Engineering, 2020, 46(10): 3509-3520.
[7] 王成山, 宋关羽, 李鹏, 等. 基于智能软开关的智能配电网柔性互联技术及展望[J]. 电力系统自动化, 2016, 40(22): 168-175.
Wang Chengshan, Song Guanyu, Li Peng, et al.Research and prospect for soft open point based flexible interconnection technology for smart distribution network[J]. Automation of Electric Power Systems, 2016, 40(22): 168-175.
[8] 杨欢, 蔡云旖, 屈子森, 等. 配电网柔性开关设备关键技术及其发展趋势[J]. 电力系统自动化, 2018, 42(7): 153-165.
Yang Huan, Cai Yunyi, Qu Zisen, et al.Key techniques and development trend of soft open point for distribution network[J]. Automation of Electric Power Systems, 2018, 42(7): 153-165.
[9] 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.
Xiao Huafeng, Wang Xiaobiao, Zhang Xing, 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.
[10] Orfanoudakis G I, Koutroulis E, Sharkh S M, et al.An extended boost three-phase transformerless PV inverter for common-mode leakage current reduction[J]. IEEE Transactions on Industry Applications, 2024, 60(1): 838-850.
[11] 胡存刚, 胡军, 陈权, 等. 基于特定谐波消除PWM的三电平有源中点钳位逆变器共模电压抑制方法[J]. 电工技术学报, 2016, 31(16): 93-102.
Hu Cungang, Hu Jun, Chen Quan, et al.Suppression method of common-mode voltage for three-level active neutral-point-clamped inverter based on selective harmonics elimination PWM[J]. Transactions of China Electrotechnical Society, 2016, 31(16): 93-102.
[12] 郭磊磊, 金楠, 李琰琰, 等. 电压源逆变器虚拟矢量模型预测共模电压抑制方法[J]. 电工技术学报, 2020, 35(4): 839-849.
Guo Leilei, Jin Nan, Li Yanyan, et al.Virtual vector based model predictive common-mode voltage reduction method for voltage source inverters[J]. Transactions of China Electrotechnical Society, 2020, 35(4): 839-849.
[13] Jayaraman K, Kumar M.Design of passive common-mode attenuation methods for inverter-fed induction motor drive with reduced common-mode voltage PWM technique[J]. IEEE Transactions on Power Electronics, 2020, 35(3): 2861-2870.
[14] Son Y C, Sul S K.A new active common-mode EMI filter for PWM inverter[J]. IEEE Transactions on Power Electronics, 2003, 18(6): 1309-1314.
[15] Hava A M, Ün E.Performance analysis of reduced common-mode voltage PWM methods and comparison with standard PWM methods for three-phase voltage-source inverters[J]. IEEE Transactions on Power Electronics, 2009, 24(1): 241-252.
[16] 徐晓娜, 王奎, 李永东. 基于调制波分解的背靠背三电平变换器共模电压消除方法[J]. 中国电机工程学报, 2022, 42(8): 2957-2968.
Xu Xiaona, Wang Kui, Li Yongdong.A common-mode voltage elimination method based on modulation signal decomposition for the back-to-back three-level converter[J]. Proceedings of the CSEE, 2022, 42(8): 2957-2968.
[17] Jayaraman K, Kumar M.Design of passive common-mode attenuation methods for inverter-fed induction motor drive with reduced common-mode voltage PWM technique[J]. IEEE Transactions on Power Electronics, 2020, 35(3): 2861-2870.
[18] 蒋栋. 电力电子变换器的先进脉宽调制技术[M]. 北京: 机械工业出版社, 2018.
[19] Lian Yujuan, Zhang Ye, Yun Wei li, et al. Common-mode resonance suppression in transformerless PWM current-source drive[J]. IEEE Transactions on Power Electronics, 2016, 31(8): 5721-5731.
[20] 薛永端, 郭丽伟, 张林利, 等. 有源配电网中性点接地方式的选择问题[J]. 电力系统自动化, 2015, 39(13): 129-136.
Xue Yongduan, Guo Liwei, Zhang Linli, et al.Selection problems of neutral grounding mode in active distribution networks[J]. Automation of Electric Power Systems, 2015, 39(13): 129-136.
[21] 郭小强, 朱铁影, 魏宝泽, 等. 飞跨电容多电平光伏逆变器共模电流抑制技术[J]. 中国电机工程学报, 2016, 36(18): 4962-4969.
Guo Xiaoqiang, Zhu Tieying, Wei Baoze, et al.Common mode current suppression technique for flying capacitor multilevel PV inverter[J]. Proceedings of the CSEE, 2016, 36(18): 4962-4969.
[22] 杨贵杰, 孙力, 崔乃政, 等. 空间矢量脉宽调制方法的研究[J]. 中国电机工程学报, 2001, 21(5): 79-83.
Yang Guijie, Sun Li, Cui Naizheng, et al.Study on method of the space vector pwm[J]. Proceedings of the CSEE, 2001, 21(5): 79-83.
[23] Bowes S R, Lai Y S.The relationship between space-vector modulation and regular-sampled PWM[J]. IEEE Transactions on Industrial Electronics, 1997, 44(5): 670-679.