Instantaneous active and reactive power (p–q) and current (Id–Iq) control strategies for extracting the three-phase reference currents for shunt active power filters are compared, evaluating their performance under different source voltage conditions with PI and fuzzy logic controllers in MATLAB/Simulink environment and also implemented using Real-Time Digital Simulator Hardware (RTDS Hardware). When the supply voltages are balanced and sinusoidal, then all control strategies with both controllers converge to the same compensation characteristics. However, when the supply voltages are distorted and/or un-balanced sinusoidal, these control strategies result in different degrees of compensation in harmonics. The p–q control strategy unable to yield an adequate solution when source voltages are not ideal. Extensive simulations are carried out with PI as well as fuzzy logic controller for both p–q and Id–Iq control strategies by considering different voltage conditions and adequate results were presented. On owing Id–Iq method with fuzzy logic controller gives away an out-standing performance under balanced, un-balanced and non-sinusoidal supply conditions. The detailed simulation and RTDS Hardware results are included.