Analysis ofDouble Loops Discrete Single InputP1 Fuzzy forSinglephaseInverter

This paperpresents ananalysis ofdouble loop PI-Fuzzy controller forasingle phaseinverter. Thescheme comprises two feedback control loopsarranged ina cascaded manner.Thecurrent inthefilter inductor and voltage across thefilter capacitor aresensed andfedbackto thesystemtoformtheinnerloopandtheouterloop, respectively. Bothloops arecontrolled byadiscrete single inputPI-Fuzzy controller. Itisderived usingthe"sign- distance" method, whichsimplifies fuzzy setintoasingle input single output system. Theworkanalyses theeffect of fuzzycontrol surface forbothloopsinimproving large- signal performance ofthecontroller. Basedontheanalysis, thereplacement ofsingle input PIFuzzyforvoltage loop withasimple discrete linear PIcontroller will bejustified. IndexTerms--PI Fuzzy,UPS inverter, Doubleloops controller