Power quality enhancement with PAC-SRF based single phase UPQC under non-ideal source voltage

This paper presents a new PAC-SRF based approach for UPQC to be used in single phase distribution systems. A necessary phase angle shift of load voltage is introduced with respect to the source voltage using the power angle control concept in order to integrate a reactive power sharing feature for series inverter part of UPQC. Synchronous reference frame (SRF) based controller is adapted for both shunt and series inverter parts of UPQC to mitigate distortion in load voltage and source current. Various power quality disturbing elements are addressed with this approach such as current and voltage harmonics, voltage sag and load reactive power demand. An SRF based approach is more helpful for power calculations under distorted conditions as compared to other control techniques. The entire system is validated by extensive simulation using MATLAB/SIMULINK and real time digital simulator (RTDS).