Simulation and RTDS Hardware implementation of 3ph 4wire SHAF for mitigation of Current harmonics Using id-iq Control strategy with PI Controller

Abstract

This paper presents a control strategy for a three phase four-wire shunt active filter. The shunt active filter is a custom-power device capable to compensate, in real time, harmonics and unbalances in an electrical system. The main objective of this paper is to analyse the performance of instantaneous real active and reactive current (id-iq) control strategy for extracting reference currents of shunt active filters under balanced, un-balanced and balanced non-sinusoidal conditions with PI controller in MATLAB/Simulink environment and also with Real Time Digital Simulator (RTDS Hardware). When the supply voltages are balanced and sinusoidal, the all control strategies are converge to the same compensation characteristics; However, the supply voltages are distorted and/or un-balanced sinusoidal, these control strategies result in different degrees of compensation in harmonics. The compensation capabilities are not equivalent, with p-q control strategy unable to yield an adequate solution when source voltages are not ideal. Extensive simulations are carried out with PI controller for Id-Iq control strategy under different main voltages. The 3-ph 4-wire SHAF system is also implemented on RTDS Hardware to further verify its effectiveness. The detailed simulation and RTDS Hardware results are included.