METHOD FOR COMPENSATING OUTPUT VOLTAGE OF PWM INVERTER

摘要

PROBLEM TO BE SOLVED: To suppress distortion of the output voltage waveform from a PWM inverter and to compensate the dead time and the forward voltage drop of an element. SOLUTION: In order to compensate for the error voltage of an inverter output voltage caused by a dead time held between the PWM pulse of a PWM inverter and the drive pulse of the semiconductor switching element in each phase arm, a PWM command pulse is corrected using the value of pulse accumulated between edge variation of the PWM command pulse and edge variation of an ON detection pulse of the semiconductor switching element as an error amount. In such a method for compensating the output voltage of the PWM inverter, a compensation amount is operated based on the forward voltage drop of the semiconductor element constituting the PWM inverter depending on the phase current polarity thereof and superposed on a voltage signal corresponding to the error amount thus correcting the PWM command pulse.