The technology of virtual synchronous generator(VSG)enables the inverter to simulate the operation mechanism of synchronous generators connected to the grid

which is beneficial to improve the stability of the power system. In order to truly simulate the working characteristics of synchronous generators

it is required that the VSG must have low voltage fault crossing capability. When an asymmetrical fault occurs

there are a large number of negative sequence components in the voltage and current

which seriously affect the quality of output voltage and current. In order to solve the problem mentioned above

firstly

based on the mathematical model of the control system

the voltage feedforward nature of the three-phase voltage source inverter is analyzed in the conventional d-q rotating coordinate system

and the voltage feedforward strategy based on the α-β coordinate system is proposed. Then

the voltage phase compensation technique is adopted to suppress the negative sequence current. Finally

through real time digital simulator model of the 5 MW energy storage VSG

single-phase and phase-to-ground fault is simulated

which verifies the correctness and effectiveness of the control algorithm.