Analysis of Parallel Photovoltaic Inverters with Improved Droop Control Method

Abstract

In this paper, an improved droop control strategy is presented to restrict the maximum power of inverters and to enhance the accuracy of reactive power sharing for parallel inverters in low voltage microgrid. The improved method can decouple active and reactive power through rotating orthogonal transformation, and extend traditional droop control to low voltage microgrid. The presented sine virtual active power-frequency droop control can restrict the maximum power of inverters without adding droop controlling unit of amplitude limits, and can enhance the accuracy of reactive power sharing. A microgrid simulation model is built in Matlab/Simulink simulation platform, and simulation analyses verify the validity and feasibility of the proposed strategy.