CIRCUIT FOR CONTROLLING CURRENTS OF A PWM INVERTER CAPABLE OF MEASURING AN OFFSET CURRENT WHEN A PWM INVERTER IS DRIVEN TO COMPENSATE FOR A CURRENT VALUE AND A METHOD FOR DETECTING AND COMPENSATING FOR AN OFFSET CURRENT USING THE SAME

摘要

PURPOSE: A circuit for controlling currents of a PWM inverter and a method for detecting and compensating for an offset current using the same are provided to detect an offset current in real time which is generated due to phase unbalance to compensate for the offset current in a current controller, thereby precisely controlling a PWM(Pulse Width Modulation) inverter. ;CONSTITUTION: A d axis proportional integration controller(10) mixes a d axis current command value with a d axis current value in which an offset current is compensated for and proportionally integrates the mixed values. A q axis proportional integration controller mixes a q axis current command value with a q axis current value in which an offset current is compensated for and proportionally integrates the mixed values. A PWM inverter unit(30) converts operation results of the d and q axis proportional integration controllers. A current sensor(40) detects a first phase current and a second phase current which are outputted from the PWM inverter unit. An offset current detecting/compensating unit(50) compensates a three-phase current after an offset current of a three-phase current is detected.;COPYRIGHT KIPO 2011