Commutation failure is one of the common faults in the line commutated converter high voltage direct current (LCC-HVDC) transmission system, which will lead to a transient voltage disturbance with the characteristic of “decrease first and then increase” at the feed end. Such a transient voltage may cause severe dynamic responses on the wind generator adjacent to the converter station, resulting in the tripping of large-scale wind turbines and even cascading failure. By analyzing the principle of the transient voltage, this paper investigates the response mechanism of doubly-fed induction generator (DFIG), involving the variation of electrical parameters and fault ride through (FRT) ability. Further verifications through simulations and experiments prove that under the disturbance of commutation failure, DFIG may suffer greater transient shocks compared to a single sag or swell disturbance event. Finally, some suggestions are put forward to mitigate the transient voltage and improve the transient response of DFIG.

中文翻译：

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LCC-HVDC系统换相失败时DFIG对暂态电压扰动的响应机制

换相失败是线路换流器高压直流（LCC-HVDC）输电系统中的常见故障之一，会导致馈端出现具有“先降后升”特征的瞬态电压扰动。这种瞬态电压可能会对换流站附近的风力发电机造成剧烈的动态响应，导致大型风力发电机跳闸，甚至发生级联故障。本文通过分析瞬态电压的原理，研究了双馈感应发电机（DFIG）的响应机制，涉及电气参数的变化和故障穿越（FRT）能力。通过仿真和实验进一步验证证明，在换相失败的干扰下，与单个下垂或膨胀扰动事件相比，DFIG 可能会遭受更大的瞬态冲击。最后，提出了一些建议，以减轻瞬态电压和改善双馈电机的瞬态响应。