Research on Optimization Method of Fault Ranging Scheme for Medium Voltage Distribution Grid Based on Combined Assignment

Aiming at the problem that it is not easy to trade-off the ranging accuracy and economy when different ranging methods are applied in distribution networks, this paper proposes a fault ranging scheme optimization method based on the combination assignment for medium voltage distribution networks. First, an evaluation system for fault ranging schemes is established from six perspectives: increased reliability of power supply, increased rate of IDG consumption, social (economic) benefits, benefits for power supply companies, communications dependency and time dependency. Then, the combined assignment method and solution method based on FAHP method and CRITIC method are proposed; Finally, the proposed method is verified to be concise, clear and feasible by taking an example of a 10KV distribution network and three typical ranging schemes in a certain area.