Determination of Phase Offsets in a Power Supply System Having Multiple Switching Converters

摘要

A controller (500) for determining a distribution of switching phases among switching elements of a power supply system The power supply system has a plurality of voltage converters, each comprising a switching element and being arranged to convert an input voltage supplied to the voltage converters to a respective output voltage by switching the switching element at a predetermined frequency. The controller (500) comprises a receiver (510) for receiving one or more signals indicative of a respective contribution from each of the voltage converters to a ripple current component of an input current of the voltage converters, and a rank determining module (520) configured to rank the voltage converters in order of decreasing contribution to the ripple current. The controller (500) further comprises a switching phase offset calculator (530) configured to calculate a respective switching phase offset that is to be applied for the switching element in each of the voltage converters by: (i) calculating respective phase offsets of the two highest ranked voltage converters that would minimise an input current ripple caused only by said two highest ranked voltage converters; (ii) calculating a phase offset of the next-highest ranked voltage converter that would minimise an input current ripple caused only by said next-highest ranked voltage converter and the voltage converters ranked higher than said next-highest voltage converter; and (iii) repeating step (ii) for each subsequent voltage converter in the ranking. The controller (500) also includes an output signal generator (540) configured to generate one or more output signals defining the calculated switching phase offsets to be applied to the switching of the respective switching elements.