多馈入直流输电系统中换相失败问题研究综述

换相失败是直流输电系统最常见的故障之一。对于多馈入直流输电系统而言,交直流系统之间的相互作用更为复杂,单个逆变站的换相失败可能引发几个逆变站相继发生换相失败,甚至导致直流功率传输的中断,影响整个交直流系统的稳定运行。文章详细分析了目前国内外多馈入直流输电系统换相失败问题的研究现状,从换相失败的机理、影响因素和判断依据出发,对近年来针对换相失败提出的预防措施和控制策略及其应用情况进行探讨,并指出准确反映换相过程的交直流系统模型的建立、多馈入直流输电系统换相失败的机理分析及其有效的控制措施和恢复策略的制定、以及换相失败的谐波影响等是今后研究的主要问题。

A Survey on Commutation Failures in Multi-infeed HVDC Transmission Systems

Commutation failures are very frequent dynamic events in high voltage DC (HVDC) transmission systems. As for multi-infeed HVDC systems, the interactions between AC and DC systems become more complicated. A failure of one inverter station may affect the operation of other adjacent inverter stations, even the power transmission of HVDC links might be consequently blocked, thus the stable operation of whole AC/DC transmission system might be affected. The authors analyze the present situation of the research on commutation failures in multi-infeed HVDC system home and abroad in detail. According to the mechanism of commutation failure, influencing factors and judgment basis, the authors research the prevention measures and control strategies proposed in recent years and their applications, and point out that following issues should be researched henceforward such as the establishment of AC/DC system model which can exactly reflect the commutation process, the analysis on commutation failures in multi-infeed HVDC transmission system, the drafting of effective control measures and recovery strategies as well as the impact of harmonics caused by commutation failures and so on.