Steady-State Models of AC Microgrid for Load Flow Solutions

Microgrid (MG) is a confined area of a power distribution network that combines Distributed Generators (conventional as well as renewable power sources) and energy storage system. Due to the integration of renewable generation sources, microgrid become more unpredictable. MG can operate in two different modes namely, 1) Grid-connected 2) Islanded mode. Due to uncertain behaviour of renewable sources, MG may possess various issues of voltage variations, frequency deviations, harmonics unbalances etc. To study the impact of these issues, it is necessary to analyze the behaviour of the MG system under normal and abnormal operating conditions, for the analysis of microgrid under normal and abnormal conditions power flow analysis tool is used. Power flow analysis is used to determine the voltages, currents, real and reactive power flows in the MG system under normal operating conditions. In this paper, the steady-state models of various components of microgrid for load flow solution have been discussed. Along with this a review of various power flow analysis techniques for AC MG system under isolated mode is also done.