METHOD AND DEVICE FOR MODIFIED SPACE VECTOR PULSE WIDTH MODULATION REDUCING DC BUS RIPPLE EFFECT IN POWER SUPPLY INVERTER

摘要

PURPOSE: A method and a device are provided for controlling a motor drive inverter in which output is controlled by modified space vector pulse width modulation, and also to reduce the size of a high-capacity capacitor. CONSTITUTION: A digital signal processor (710) calculates a required instantaneous duty ratio of an inverter output waveform such that the effect of ripple component of a line voltage is cancelled by an input ripple signal extracted from the line voltage and a speed/position feedback signal (702) related to the inverter output for driving a motor (705). An inverter PWM drive controlled by the instantaneous duty ratio is applied to the gates of N channel MOSFET transistors (100-102 and 110-112) forming the inverter and the inverter output is controlled by modified space vector pulse width modulation.