An Efficient Power Flow Improvement in Transmission Line using UPFC

Abstract

A new reactive powercoordination controller has been designed to limitexcessive voltage excursions during reactive powertransfers. The shunt converter of the UPFC controls theUPFC bus voltage/shunt reactive power and the dc linkcapacitor voltage. The series converter of the UPFCprovides simultaneous control of real and reactive powerflow in the transmission line the shunt converter has beenmodeled as a 4-module converter. The series converterconsists of two sets of converters. One set of converter isused for the real power flow control and the other set ofconverter is used for the reactive power flow control.Recent advances in high voltage IGCT technology allowfor higher switching frequencies with lower losses. Thisallows for practical implementation of PWM control. Theswitching frequency for the converters has been chosen tobe nine times the fundamental. Here we use matlab/simulink for the simulation purpose and outputs areverified in the scope.