| 引用本文: | 蔡宜君,文明浩,陈玉,等.LCC-MMC混合直流输电系统整流侧故障穿越控制策略[J].电力系统保护与控制,2018,46(14):1-8.[点击复制] |
| CAI Yijun,WEN Minghao,CHEN Yu,et al.Control strategy of LCC-MMC hybrid HVDC system under rectifier side fault[J].Power System Protection and Control,2018,46(14):1-8[点击复制] |
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| 摘要: |
| 整流侧采用电网换相换流器(Line Commutated Converter, LCC)，逆变侧采用模块化多电平换流器(Modular Multilevel Converter, MMC)构成的混合直流输电系统，结合了LCC、MMC的优点；同时，当MMC为半桥子模块和全桥子模块各占50%的混合型MMC时，系统具有较强的交直流故障穿越能力。针对整流侧交流系统严重故障下半桥子模块和全桥子模块电容电压不平衡的问题，提出一种改进的环流控制策略。改进的环流控制策略通过检测MMC的运行工况，调整环流控制器的参考值，从而使桥臂电流具有正负交替的特性。其次，提出基于虚拟电阻和电流指令限值的故障暂态电流抑制策略，能够抑制故障穿越期间交直流电流的振荡，确保系统安全稳定运行。基于PSCAD/EMTDC仿真平台，搭建LCC-MMC混合直流输电系统，仿真验证了所提控制方法的有效性。 |
| 关键词: 混合直流输电系统 混合型模块化多电平换流器 电容电压平衡 环流 故障穿越 |
| DOI：10.7667/PSPC171006 |
| 投稿时间：2017-07-07修订日期：2017-09-27 |
| 基金项目:国家重点研发计划项目(2016YFB0900600);国家自然科学基金项目(51477061) |
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| Control strategy of LCC-MMC hybrid HVDC system under rectifier side fault |
| CAI Yijun,WEN Minghao,CHEN Yu,SHI Yaguang,QIN Yu |
| (State Key Laboratory of Advanced Electromagnetic Engineering and Technology, Huazhong University of Science and Technology, Wuhan 430074, China) |
| Abstract: |
| The hybrid High Voltage Direct Current (HVDC) transmission system that the rectifier adopts Line Commutated Converter (LCC) and the inverter adopts Modular Multilevel Converter (MMC), combines the advantages of LCC and MMC. And when the MMC is composed of fifty percent Half Bridge Sub-Modules (HBSMs) and fifty Percent Full Bridge Sub-Modules (FBSMs), the system has a strong capability to deal with AC and DC faults. In view of the problem that the HBSMs’ and FBSMs’ capacitor voltages can not be balanced under the serious rectifier AC fault, an improved circulation control strategy is proposed. It can adjust the reference value of the circulation component by detecting the running condition of MMC so that the arm current has positive and negative segments in each cycle. Then, a control strategy based on virtual resistance and current reference limitation is proposed to suppress the oscillation of the system and ensure the system to run safely and stably during the fault ride-through period. Finally, a LCC-MMC hybrid HVDC transmission system is built in PSCAD/EMTDC and the simulation results verify the effectiveness of the proposed method. This work is supported by National Key Research and Development Program of China (No. 2016YFB0900600) and National Natural Science Foundation of China (No. 51477061). |
| Key words: hybrid HVDC system hybrid MMC capacitor voltage balancing circulating current fault ride-through |
