A simple network reduction technique for large autonomous microgrids incorporating an efficient reactive power sharing

Reactive power sharing continues to be a challenge for an autonomous Microgrid (MG) since reactive power sharing is largely affected by the mismatch in line impedance and the asymmetry of local loads. Several reactive power sharing methods have been proposed in an autonomous MG but their effectiveness on large MG systems has not been explored much. This paper considers a standard IEEE 38 bus autonomous MG to study the effectiveness of proportionate power sharing. A simple network reduction technique has been proposed to obtain an equivalent reduced MG for which a reactive power sharing technique is applied. The most feasible method has been analyzed and the communication based reactive power sharing along with droop controller is proved to be the popular and most generalized strategy for effective power sharing. MATLAB-Simulink tool is used to validate the power sharing with equal and unequal DG ratings in a standard IEEE 38 bus autonomous MG system with network reduction.