Abstract：An improved virtual impedance strategy with adaptive reactive power equalisation and bus voltage

compensation functions was proposed to address the reactive power equalisation and bus voltage drop issues in

parallel inverters in island microgrids. By introducing an enhanced power decoupling strategy based on a secondorder generalized integrator（SOGI），the harmonic virtual voltage drop problem under nonlinear loads was solved，and the tracking performance of the PI controller was improved. Then，an adaptive virtual voltage drop correction term was introduced to eliminate the influence of line impedance，and a method for selecting the virtual voltage drop correction coefficient was proposed. Finally，the effectiveness of the proposed strategy was verified through simulations，demonstrating improved reactive power equalisation precision and bus voltage compensation in complex operating conditions.

      Key words：shunt inverter；virtual impedance；reactive power equalisation；voltage compensation