Research on the relay protection system of micro-grid

Abstract

In this paper, the necessity of the protective relay of the micro-grid is described as the anti-islanding protection and Low Voltage Ride Through (LVRT), and the fault characteristics of the renewable energy sources are analysed. The applicability of over-current protection, distance protection, differential protection, pilot protection, voltage protection and frequency protection is also analysed. Three novel solutions of protection have been proposed and discussed in this paper. After the stability of MG with external faults and internal faults is analysed, the protection configuration principle of micro-grid is proposed.