Optimal Placement of Energy Storage Devices in Microgrids Via Struture Preserving Energy Function

Abstract

As system transient stability is one of the most important criterions of microgrid (MG) security operation, and the performance of an MG strongly depends on the placement of its energy storage devices (ESDs), optimal placement of ESDs for improving system transient stability is required for MGs. An MG structure preserving energy function is firstly developed for voltage source inverter based MGs since the existing energy functions, based on synchronous generators and the conventional power system, are not applicable for MGs. The concept of internal potential energy of distributed energy resource is presented instead of the kinetic energy term in traditional energy function. And then, a novel approach for the optimal placement of ESDs is proposed based on MG structure preserving energy function for improving MG transient stability. Simulation and experimental results show that the proposed method can be used to find the optimal placement of ESDs, and to improve the system stability effectively.