关键词: 配电系统, 分布式电源, 继电保护

Abstract:

With the interconnection of distributed generations (DGs),the network structure and fault current ofpower distribution system are changed,which leads to the mis- operation,malfunction and sensitivity degradation ofprotective relays.In order to quickly clear the fault region and well play a supporting role of DGs for the system,anew protection scheme is introduced based on the traditional relay protection scheme of power distribution system.In the proposed scheme,the directional pilot protection is adopted and a acceleration module,a direction module,a voltage detection module and an inverse time over- current protection module are employed to avoid the fault currentthat cannot be eliminated due to the protection and the breaker malfunction.Simulated results of PSCAD/EMTDCon a 10kV power distribution system with DGs verify the effectiveness of the proposed scheme.

Key words: power distribution system, distributed generation, relay protection