A cost-effective fault management system for distribution systems with distributed generators

Fault Management System (FMS) is one of the main functions in Distribution Automation System (DAS); however, the conventional FMS cannot be used in distribution systems with Distributed Generators (DGs) due to the lack of directional function. The directional fault detection device is expensive due to the expensive directional module used. In a wide-ranging distribution system, the investment cost will be very high if the fault detecting devices are expensive. Therefore, the design and implementation of a cost-effective FMS for distribution system with DGs is necessary. A Multi-Level Fault-Current Indicator (MLFCI) having a plurality of reed switches used to detect different current levels is proposed in this paper. The hardware prototype is designed and implemented. An algorithm used to locate fault based on the different fault current levels is derived. A MLFCI-based FMS for distribution systems with DGs is then realized. Experimental results demonstrate the feasibility of the proposed MLFCI. Simulation results are then used to demonstrate the validity of the proposed MLFCI-based FMS for distribution systems with DGs.