LAUSR

Unified power quality conditioner (UPQC) has been used to stabilize the voltage profile with reduced harmonics. Thus, it is important to do the impact study of UPQC over distribution system. But iterative load flow method sometime fails to converge with rise in system complexity. Thus, recursive holomorphic embedding load flow is best suited over here. This article proposes a recursive mathematical modeling of UPQC using holomorphic embedding method. This holomorphic embedded model of UPQC is based on series and shunt converters operation determined by phasor diagram. Different operating modes of UPQC are also modeled and tested. The proposed models have been tested over IEEE 13, 123 bus distribution test systems and a 19 bus practical Indian distribution grid. A rigorous comparative study with existing iterative load flow methods has been done. On analyzing the results, it shows great efficacy and reliability in terms of voltage sag mitigation and total harmonic distortion compared to conventional methods.