Research on Improving the Power Distribution of Parallel System and Enhancing the Voltage Drop at the PCC Based on Adaptive Virtual Impedance Droop Control

This paper addresses power distribution imbalances and insufficient voltage support at the Point of Common Coupling (PCC) in parallel inverter systems. Traditional droop control enables communication-free autonomous power distribution but suffers from circulating currents (caused by parameter/impedance mismatches) and degraded PCC voltage stability under heavy loads. To overcome these limitations, we propose an improved control strategy featuring: An adaptive virtual impedance loop based on a consensus algorithm, dynamically reconfiguring equivalent output impedance to suppress circulating currents; A secondary voltage compensation term that mitigates PCC voltage drops through reactive power normalization. Simulation results demonstrate over 40% reduction in voltage fluctuations and precise power sharing in a dual-inverter parallel system. The proposed approach enhances system stability while maintaining the plug-and-play advantages of conventional droop control.