Voltage Sag, Swell and Harmonics Mitigation by Solar Photovoltaic fed ZSI based UPQC

Abstract

This paper presents a solar photovoltaic (SPV) fed impedance or Z-source inverter (ZSI) based Unified Power Quality Conditioner (UPQC) for the alleviation of power quality events such as voltage sag, swell and harmonics with sudden addition or removal of a nonlinear load. The unit vector template (UVT) control technique is used to produce the reference voltage and current signals to control the operation of SPV fed ZSI-UPQC. A novel hybrid technique is also proposed for optimum maximum power point tracking (MPPT) with the combination of perturbation and observation (P&O) technique and incremental conductance (Inc) technique. The response of SPV fed ZSI-UPQC for mitigation of supply voltage sag, swell and harmonics are investigated and compared with SPV fed voltage source inverter (VSI) based UPQC (VSI-UPQC) and SPV fed current source inverter (CSI) based UPQC (CSI-UPQC).