Methods and apparatus for controlling power switches via a digital communication bus

Abstract

Methods and apparatus are provided that can be used to control a set of power switches operating as a power converter. The method comprises providing a set of power switches and at least one switch driver, each power switch being operable to connect and disconnect one of a set of input power line to an output power line, each switch driver setting the state(s) of an associated power switch or switches; generating by a controller a set of switch commands, each command indicating a desired state of a respective one of said power switches at a moment in time; sending each switch command from the controller to a driver module containing the switch driver associated with the respective power switch; receiving at each driver module switch commands for its associated power switch(es) and causing each switch driver to set the state(s) of the appropriate power switch(es) accordingly; wherein the step of sending said switch commands comprises multiplexing commands for at least a subset of said switches into a series of multi-bit command frames and transmitting said command frames on a serial communication channel, and wherein the step of receiving said switch commands comprises receiving said multi-bit command frames from said communication channel and extracting individual switch commands therefrom. The method and apparatus can be used for example in a UPS system.