SRF-based control of unified power quality conditioner for power quality enhancement

Power quality has turned into a vital component in power systems, for consumer and household applications with wide usage of different electric and electronic equipments. The primary causes of a poor power quality are harmonic currents, supply-voltage variations and so forth. UPQC is a unique device which compensates harmonic currents and mitigates voltage variations at load side. This paper presents Synchronous Reference Frame control technique for UPQC to compensate power quality problems. Hysteresis Current Controller is used for generation of switching pulses to series and shunt APF´s. Simulations are carried out in Matlab/Simulink for a three phase three wire system under distorted supply voltage and non-linear unbalanced load conditions. Simulation results prove that under unbalanced and nonlinear load conditions, UPQC eliminates the effect of supply voltage variations and harmonic currents on the power line.