基于主动探测式的混合MMC直流输电系统单端量故障定位

In order to further improve the performance of traditional fault location methods and ensure the reliability of DC line fault recovery, an active detection signal injection strategy is proposed based on the high controllability of hybrid MMC converter considering the influence of fault impedance, frequency-dependent parameters effect, numerical differential error and distributed capacity of transmission line. Based on the fault current limiting strategy and the idea of parameter identification, the compensation strategy of distributed parameter model is introduced to construct the parameter identification fault location equation with fault distance and transition resistance parameters to realize fault location. The simulation results show that the proposed fault location schemes can accurately identify the fault area, and are applicable for long DC lines and less affected by fault impedance and sampling rate.