To reduce the probability of commutation failure (CF) of a line commutated converter based high-voltage direct current (LCC-HVDC) transmission, a DC chopper topology composed of power consumption sub-modules based on thyristor full-bridge module (TFB-PCSM) is proposed. Firstly, the mechanism of the proposed topology to mitigate CF is analyzed, and the working modes of TFB-PCSM in different operation states are introduced. Secondly, the coordinated control strategy between the proposed DC chopper and LCC-HVDC is designed, and the voltage-current stresses of the TFB-PCSMs are investigated. Finally, the ability to mitigate the CF issues and the fault recovery performance of LCC-HVDC system are studied in PSCAD/EMTDC. The results show that the probability of CF of LCC-HVDC is significantly reduced, and the performances of fault recovery are effectively improved by the proposed DC chopper.

中文翻译：

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基于直流斩波器的线路换向变流器高压直流输电换向故障的缓解

为了降低基于线路换向转换器的高压直流（LCC-HVDC）传输的换向失败（CF）的可能性，直流斩波器拓扑由基于晶闸管全桥模块（TFB-PCSM）的功耗子模块组成）。首先，分析了所提出的拓扑结构减轻CF的机理，并介绍了TFB-PCSM在不同工作状态下的工作模式。其次，设计了所建议的直流斩波器与LCC-HVDC之间的协调控制策略，并研究了TFB-PCSM的电压-电流应力。最后，在PSCAD / EMTDC中研究了减轻CF问题的能力和LCC-HVDC系统的故障恢复性能。结果表明，LCC-HVDC CF的概率大大降低，