陆翌,华文,金玉琪,董玮,倪晓军,邹强,吴小丹
LU Yi,HUA Wen,JIN Yuqi,DONG Wei,NI Xiaojun,ZOU Qiang,WU Xiaodan

• 1:国网浙江省电力有限公司电力科学研究院
• 2:国网浙江省电力有限公司
• 3:南京南瑞继保电气有限公司

摘要(Abstract)：

针对基于M3C（模块化多电平矩阵式变换器）的柔性低频输电系统的两相运行方式，建立了低频系统复合序网，对常规控制策略下低频输电线路和M3C的稳态运行特性进行分析。分析表明，线路中将出现与正序电流等幅反相的零序电流，同时也会出现零序电压和负序电压；采用低频侧定功率控制和负序电流抑制策略的M3C子换流器间电容电压不均衡，M3C电容电压平均值存在2倍频振荡分量。在PSCAD/EMTDC中搭建双端型柔性低频输电系统仿真模型，验证了所得结论的正确性。
The two-phase operation mode of a flexible low-frequency transmission system is based on the M3C(modular multilevel matrix converter). This paper establishes a complex sequence network for the low-frequency system to analyze the steady-state operation characteristics of low-frequency transmission lines and M3C under the conventional control strategy. The analysis shows that: 1) There appears zero-sequence current that shares equal amplitude and opposite phase of the positive-sequence current in transmission lines; 2) The zero-sequence voltage and negative-sequence voltage can also appear in the transmission lines; 3) There is an unbalanced capacitor voltage between M3C sub-converters with fixed power control on the low-frequency side and negative sequence current suppression strategy; 4) There is a double frequency oscillation component in the M3C average capacitor voltage. A simulation model of the dual-terminal flexible low-frequency transmission system is built in PSCAD/EMTDC, and the correctness of the obtained conclusions is verified.

关键词(KeyWords)： 柔性低频输电;两相运行;复合序网
flexible low-frequency transmission;two-phase operation;complex sequence network

Abstract:

Keywords:

基金项目(Foundation): 国网浙江省电力有限公司科技项目（2021ZK06）

作者(Author): 陆翌,华文,金玉琪,董玮,倪晓军,邹强,吴小丹
LU Yi,HUA Wen,JIN Yuqi,DONG Wei,NI Xiaojun,ZOU Qiang,WU Xiaodan

DOI: 10.19585/j.zjdl.202212012

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