利用全桥MMC注入特征信号的直流自适应重合闸方法

Electrical coupling between transmission lines is the premise of single-/three-phase adaptive reclosing. Considering the relationship between DC transmission lines in steady state, this paper presents a method injecting characteristic signal to a faulty DC line to identify fault property, making full use of the control characteristics of full bridge based converter without circuit breaker. The problem of non-selective restart of current HVDC transmission is solved. In this paper, the selection principle of characteristic signals, and the principle and regulation of the characteristic signal are analyzed in detail. Then, a characteristic signal is injected into the DC faulty line according to additional control strategy and the fault property is discriminated based on the propagation characteristics of the faulty line and the healthy line. Simulation results verify validity of the method distinguishing the fault properties by injecting characteristic signal using full bridge based converter.