Simple control method for parallel connected three-phase PWM converters

This paper presents a current-controlled parallel connected three phase converters scheme. Two voltage source inverters with a front end diode rectifier are directly paralleled without intermodule reactors. The proposed method divides the switching cycle evenly between the equally rated converters, and each converter employs just one PI regulator to get good current characteristics, both in steady states and transient states. Unlike in most previous studies, the converters utilize local feedback information to obtain equal current sharing without using any circulating current control scheme. Using MATLAB/Simulink, simulation results are given to verify the control proposed.