Short-circuit calculation method for islanded micro-grid based on master-slave control

The quick response of inverter integrated distribution generation (HDG) source under fault makes the equivalent circuit of sequence network different from traditional power system. Based on the control strategy and the equivalent model of inverter integrated distributed generation (IIDG) under fault, IIDG source can be taken as voltage source or current source in sequence-network. With the analysis of sequence network for micro-grid with multi-DG integrated, this paper presents a novel short-circuit calculation method for islanded micro-grid based on master-slave control. The proposed short-circuit calculation method is based on the equivalent model of HDG considering unbalanced control and, consequently, is applicable to unbalanced systems. PSCAD/EMTDC simulation studies have demonstrated the proposed scheme can accurately figure out the fault current.