Investigation of The Circulating Current Based on The Power Sharing with The Droop Control Method in The Parallel-Connected Inverters

This paper focuses on investigating circulating currents arising from unequal power distribution within a parallel-connected inverter system. Circulating currents emerge when there are disparities in the output voltages of inverters linked in parallel. Unequal power sharing situations can also trigger these circulating currents. Multiple control strategies exist to attain balanced power sharing in parallel systems. This study achieves power sharing equilibrium through the implementation of a droop control approach. The experimental setup includes two parallel-connected inverters, modeled using MATLAB/Simulink. Circulating currents are simulated across different loading rates, ranging from 10% to 50%, between these inverters. The simulation results demonstrate that circulating currents are effectively eliminated when power is evenly shared among the inverters. Conversely, an increase in circulating current is observed with an increasing imbalance in power distribution ratios among the inverters.