When using conventional source current, the harmonic diminution methods failed miserably under a variety of load scenarios. Many dependability problems in harmonics mitigation are caused by nonlinear loads. Filters diminish harmonics and problems with power quality. These filters are expensive because they provide a dynamic response under various load conditions. More effective voltage stability is offered by the new Unified Power Quality Controller (UPQC) with its series and shunt compensator in addition to more secure power systems throughout a range of load situations. The Modified Synchronous Reference Frame Theory (SRF) theory is utilised to create the reference current from the AC source current. Counter to the load harmonics, SRF theory generates sinusoidal harmonics. In the PCC, this UPQC has the ability to inject or absorb reactive power. The DC connection capacitor receives voltage from a tuned PI controller that is based on the GWO Optimisation approach. The shunt and series compensator receive PWM pulses from the hysteresis current controller and D-Q theory. Lastly, use the MATLAB 2021a/Simulink programme to do a number of numerical simulations in order to validate the suggested controls. The THD output of the proposed UPQC parameter was found to be 1.49%.