| 引用本文: | 陈 果,龚春阳,朱丽华,等.基于I-DPWM的三电平中点钳位光伏逆变器漏电流抑制方法[J].电力系统保护与控制,2023,51(11):119-130. |
| CHEN Guo,GONG Chunyang,ZHU Lihua,et al.Leakage current suppression method of a three-level neutral point clampphotovoltaic inverter based on I-DPWM[J].Power System Protection and Control,2023,51(11):119-130 |
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| 摘要: |
| 对于三电平中点钳位光伏逆变器，基于断续脉宽调制(discontinuous pulse width modulation, DPWM)并通过选择特定矢量进行钳位控制的方法，存在矢量分解计算时间长、注入共模电压分量和漏电流过大等不足。对此，提出了一种基于I-DPWM的三电平中点钳位光伏逆变器漏电流抑制方法。通过计算各类DPWM等效调制波来解析注入的低频共模电压分量。针对低频共模电压分量最小的DPWM1，在低频共模电压不连续点注入新的零序分量，通过减小低频共模电压来抑制漏电流幅值。同时，采用载波实现DPWM，免去了复杂的矢量运算。最后，在Matlab/Simulink平台建立了20 kW三电平中点钳位光伏逆变器的仿真模型，同时结合所设计的125 W实验样机验证了所提方法的有效性。 |
| 关键词: 三电平中点钳位型逆变器 漏电流抑制 I-DPWM 载波调制 |
| DOI：10.19783/j.cnki.pspc.221140 |
| 分类号: |
| 基金项目:国家重点研发计划项目资助(2018YFB1503001)；上海市科委科技计划项目资助(21DZ1207300)；上海市经信委工业强基计划项目资助(GYQJ-2022-1-14) |
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| Leakage current suppression method of a three-level neutral point clampphotovoltaic inverter based on I-DPWM |
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CHEN Guo1, GONG Chunyang2, ZHU Lihua3, BAO Jun4, CHEN Hui2, WANG Zhixin1
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1. School of Electronic Information and Electrical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China;
2. Shanghai University of Electric Power, Shanghai 200090, China; 3. Shanghai Chint Power System Co., Ltd.,
Shanghai 200210, China; 4. Shanghai Xilong Technology Co., Ltd., Shanghai 201517, China
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| Abstract: |
| For three-level neutral point clamped photovoltaic inverters, a suppression method based on discontinuous pulse width modulation (DPWM) and with the selection of a specific vector for control, has shortcomings such as long calculation time of vector decomposition, large injection common-mode voltage component and large leakage current. In this paper, a leakage current suppression method based on I-DPWM for a three-level neutral point clamped photovoltaic inverter is proposed. The injected low-frequency common-mode voltage component is analyzed by calculating various DPWM equivalent modulation waves. Aiming at DPWM1, which has the lowest low-frequency common-mode voltage component, a new zero-sequence component is injected at the low-frequency common-mode voltage discontinuity point, and the leakage current amplitude is suppressed by reducing the low-frequency common-mode voltage. At the same time, a carrier is adopted to realize the DPWM, without complex vector operation. Finally, a simulation model of a 20 kW three-level neutral point clamp photovoltaic inverter is established on the Matlab/Simulink platform, and the effectiveness of the proposed method is verified by combining with the designed 125 W experimental prototype. |
| Key words: three-level NPC inverter leakage current suppression I- DPWM carrier modulation |
