Application of a novel virtual synchronous generator technology in islanded microgrid

A novel virtual synchronous generator (VSG) control strategy is proposed by adding the “swing equation” of the rotor and the “virtual swing equation” of the voltage control to the active loop and reactive loop based on the droop control in this paper. The islanded microgrid with this VSG method not only has damping and inertia in active loop and reactive loop as the traditional synchronous generator, but also can compensate the voltage drop caused by droop control and the line impedance. Most importantly, the VSG method proposed in this paper can share the load accurately in proportion to the power ratings of different islanded microgrids without meeting the impedance matching conditions. This paper introduces the principle of the novel VSG control strategy, establishes the mathematical model of this VSG method and analyzes the requirements of different islanded microgrids with this VSG control method running in parallel operation to achieve accurate proportional load sharing in detail. MATLAB/Simulink simulation results of an islanded microgrid running independently and two islanded microgrids running in parallel operation based on this VSG method are given. The simulation results show the effectiveness of the proposed control strategy.