Detection of three-phase currents in space-vector PWM inverters with only one DC link current sensor

Abstract

A method for detecting the three-phase currents of a voltage-fed pulsewidth modulated (PWM) inverter is proposed by utilizing only one current sensor placed on the DC-link. The estimation scheme is employed to reduce the detection errors and a recursive least square method (RLSM) is applied to identify the system parameters for compensating the parameter mismatching problem. The proposed method is simple and reduces the cost. It also has the small detection errors and provides the information on system parameters.