Control methods for the synchronisation and phase shift of the pulse width modulation (PWM) strategy of power converters

摘要

A method and apparatus for controlling a plurality of power converters that can be used to interface to a supply network is described. The power converters include a network bridge operating in accordance with a pulse width modulation (PWM) strategy which has same switching period, causing an unwanted harmonic in the supply network voltage. The method provides the switching period of the PWM strategy of each network bridge with a different time offset relative to a time datum such that the at least one unwanted harmonic in the supply network voltage is at least partially cancelled.