Accurate reactive power sharing and voltage-frequency recovery strategy for multiple grid-forming converters based on consensus algorithms

In isolated AC microgrids, parallel multi-inverter systems face challenges in precisely distributing reactive power output from distributed generation (DG) units due to varying DG parameters and mismatched line impedances. To address this, this paper adopts an adaptive virtual impedance control method based on the consensus algorithm to achieve proportional power allocation among DGs according to their rated capacities, thereby suppressing circulating currents between inverters. Additionally, voltage restoration control based on the consensus algorithms compensates for voltage sags caused by line impedance and virtual impedance control, restoring the common bus voltage to its rated value. Subsequently, a frequency restoration control based on the consensus algorithms compensates for frequency deviations caused by the failure to balance the active reference value with the active load in real time, restoring the common bus frequency to its rated value. Finally, a hardware-in-the-loop test platform based on a two-converter parallel system was established to validate the effectiveness of the proposed control strategy. Compared to existing consensus control strategies, the proposed coordinated control structure is more concise and simultaneously achieves the triple objectives of reactive power sharing, voltage restoration, and frequency restoration. • Proposes a consensus-algorithm-based coordinated control for multiple grid-forming converters. • Achieves accurate reactive power sharing via adaptive virtual impedance, improving the ratio from 1.3:1–1:1. • Simultaneously restores common bus voltage and frequency to their rated values. • Suppresses circulating currents and reduces output current THD from 6.48 % to 0.5 %.