A CURRENT SOURCEINVERTER FORUPS

In thispaper,anuninterruptible powersupply (UPS)systemusinga currentsourceinverteris proposed.A singlephaseanda threephaseloadcommutatedcurrentsourceinvertersuitableforthis UPSsystemispresented.Theloadcommutation is achievedby selecting theoutputfiltertomaintain a netleadingpowerfactorat theinverteroutput overtheoperatingloadrange.A steadystateanalysisof theinverterpowercircuitsis given.The analysisisbasedon usingtheharmonicseriesof theinverteroutputcurrenttoobtainthecircuit voltagesandcurrents.Thetheoretical resultspresentedin thispaperareverifiedon experimental modelsforboththesinglephaseandthethreephase inverters.