基于电流积分的HVDC系统阀短路故障分类与定位方法

为实现高压直流输电(HVDC)系统阀短路故障的快速有效处理,提出了一种基于电流积分的阀短路故障分类与定位方法。定义六脉动换流器电流路径中的"交流截面""上桥臂截面"和"下桥臂截面",计算出采样窗内流过各截面的电流积分,以其大小关系为判据,区分交流侧相间短路、桥臂短路和直流出线短路3种典型阀短路故障类型;针对桥臂短路故障,进一步计算出采样窗内各交流支路和其对应桥臂支路的电流积分差值,定位故障桥臂。基于CIGRE模型的仿真结果表明,该方法能快速分类与定位阀短路故障,且不受故障时刻、噪声和采样窗长的影响。

Current Integral Based Method for Valve Short-circuit Fault Classification and Location in HVDC System

In order to complete fast and effective valve short-circuit fault clearance in the high voltage direct current(HVDC)system, a current integral based method for valve short-circuit fault classification and location is proposed. The AC section, upper bridge arm section and lower bridge arm section in current paths of six-pulse rectifier is defined. By comparing the integral value of the current flowing through each section in the sampling window, the typical valve short-circuit fault including AC short-circuit fault, DC short-circuit fault and bridge arm short-circuit fault can be classified. In the event the bridge arm short-circuit fault occurs, by calculating the current integral value difference between AC branch and the corresponding bridge arm branch in the sampling window, the fault bridge arm can be located. The simulation results based on CIGRE model show that the proposed method is able to classify and locate the valve short-circuit fault rapidly and reliably, its performance unaffected by the fault time, noise and the length of the sampling window.