Direct-current power distribution network single-pole grounding fault section positioning method and system

The invention discloses a method and a system for positioning a single-pole grounding fault section of a direct-current power distribution network, and the method comprises the steps: cooperatively inputting a resonant branch to inject a current detection signal through an MMC additional control strategy, then setting an action sequence of a load switch/circuit breaker based on a delay level difference principle, and completing the positioning and isolation of a fault section based on single-end information. The section positioning method avoids the installation of additional devices, and has the characteristics of high sensitivity and no need of double-end communication. 本发明公开了一种直流配电网单极接地故障区段定位方法及系统，通过MMC附加控制策略协同投入谐振支路注入电流探测信号，然后，基于延时级差原则设置负荷开关/断路器的动作顺序，基于单端信息完成故障区段的定位和隔离。区段定位方法避免了安装附加装置，具有灵敏度高、无需双端通信的特点。