According to the need for single-phase voltage inverter parallel operation

a new control scheme is introduced. In the scheme a proportional controller is used in current-inner-loop and a proportional resonant controller is adopted in voltage-outer-loop. By achieving control block diagram of the control system

the transfer function of single-phase voltage inverter power is deduced and the design process of the control parameters is demonstrated based on the transfer function. Then this paper explores inverter power parallel system of different loads with equal and unequal capacities. Its simulation results show that the suggested controller is of favorable applicability and significance.