Power converter with dead time variation for spreading a distortion

摘要

A power converter receives a DC supply voltage on a phase leg. The phase leg includes an upper switching device and a lower switching device coupled across the DC link, wherein a node between the upper and lower switching devices is configured to be coupled to a load. A gate driver is coupled to the phase leg, activating the corresponding upper switching device in accordance with an upper gate signal, and activating the corresponding lower switching device in accordance with a lower gate signal in response to a pulse width modulation (PWM) control signal having a PWM frequency. The gate driver converts among several alternating paired sets of dead-time inserted signals. Each paired set of dead time-inserted signals corresponds to a different distortion of a current flowing in the load, so that an overall distortion is dispersed.