Control Strategy for Line Overload and Short Circuit Current of Networked Distribution Systems

Abstract

The expected increase in renewable energy sources (RESs) and electric vehicles (EVs) connected to distribution systems will result in many technical constraints. A meshed network is a promising solution; however, some remarkable challenges must be overcome. Among these, this paper mainly focuses on the line overload and short circuit current of a networked distribution system (NDS) in Korea, an advanced form of meshed network. An NDS refers to a system in which there exists permanent linkages between four feeders and N x N communication-based protection. We propose a method, which employs the tap changing control algorithm of the series reactor to control line overload and short circuit current. MATLAB/Simulink was used to evaluate the proposed method. Three different types of distribution system were employed. First, the utilization rate and feeder imbalance were analyzed in steady-state condition. Subsequently, the short circuit current was analyzed in short circuit condition. The results revealed that the proposed method can effectively prevent line overload in up to 82.7% of cases, enhance the utilization rate by up to 79.9%, and relieve the short circuit current; that is, it can contribute to system stability and the economic operation of an NDS.