一种基于短路电抗器的直流配网故障保护方法研究

Study on Fault Protection of DC Distribution System Based on Short-Circuit Reactor

摘要: 本文在分析多端直流配电系统故障过程的情况下，得出多端直流配电系统故障时的等效电路，并在此基础上计算多端直流配电系统的故障电流，分析该系统的故障特性，并通过仿真发现该系统发生故障时，依据短路电流特性很难区分母线故障还是馈线故障。因此，本文提出在馈线出口处加装串联短路电抗器，使得母线故障短路电流和馈线故障短路电流在幅值特征和波形特征能够较好区分，为多端直流配电系统的保护提供了判据。

Abstract: This paper analyzes the fault process of a multi-terminal DC power distribution system to obtain the equivalent circuit when the multi-terminal DC power distribution system fails, and then calculates the fault current of the multi-terminal DC power distribution system and analyzes the fault characteristics of the system. Through simulation, it is found that when the system fails, it is difficult to distinguish between bus faults and feeder faults based on the short-circuit current charac-teristics. Therefore, this article proposes to install a series reactor at the outlet of the feeder so that the short-circuit current of the bus fault and the short-circuit current of the feeder fault can be distinguished well in the amplitude characteristics and waveform characteristics, thus providing a criterion for the protection of the multi-terminal DC power distribution system.