Probabilistic analysis of commutation failure in LCC-HVDC system considering the CFPREV and the initial fault voltage angle
Probabilistic analysis of commutation failure in LCC-HVDC system considering the CFPREV and the initial fault voltage angle
复制标题
考虑CFPREV和初始故障电压角的LCC-HVDC系统换相失败概率分析
DOI：
10.1109/tpwrd.2019.2925399
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发表时间：
--
影响因子：
4.4
通讯作者：
Cheng Shijie
中科院分区：
文献类型：
--
作者：
Yao Wei;Liu Chang;Fang Jiakun;Ai Xiaomeng;Wen Jinyu;Cheng Shijie
深入研究了基于线路换相换流器的高压直流（LCC-HVDC）系统换相失败机理。分析中从电压-时间域的角度考虑了换相失败预防控制和初始故障电压角。结果表明，当逆变器母线电压降较小时，IFVA是导致换相失败的主要因素之一，CFPREV进一步加剧了IFVA对换相失败的影响，而当逆变器母线电压降较大时，直流电流的波动在换相失败中起主导作用。提出了一种定量划分交流故障严重程度的方法，以确定换相失败的主导因素。建立了换相失败概率与IFVA之间的关系，提出了换相失败概率的计算方法。研究了CFPREV输出的动态特性对研究结果的影响。利用PSCAD/EMTDC软件对一个典型的直流输电系统进行了仿真计算，验证了理论分析的正确性和所提出的计算方法的有效性。
This paper investigates the in-depth mechanism of commutation failure for a line-commuted converter-based high-voltage direct current (LCC-HVDC) system. The commutation failure prevention control (CFPREV) and the initial fault voltage angle (IFVA) are considered from the view of the voltage-time area (VTA) in the analysis. It is revealed that the IFVA is among the dominant factors for commutation failures when the voltage drop of the inverter bus is relatively small, and CFPREV further intensifies the impact of the IFVA on commutation failures, while the fluctuation of the direct current plays a dominant role in commutation failures under a greater voltage reduction at the inverter bus. A quantitative division of the severity of AC faults is proposed to determine dominant factors for commutation failures. The relationship between the chance of commutation failures to occur and the IFVA is built, and the method used for computing probability of commutation failures is proposed. The influence of the dynamic of CFPREV output on our research is studied. Simulations based on a typical monopole LCC-HVDC system using PSCAD/EMTDC software are conducted to verify the correctness of the theoretic analysis and the effectiveness of the proposed computing methods.