Comparative evaluation of current reference extraction methods for single-phase shunt active power filters

In this paper, two current reference extraction methods for harmonic compensation in single-phase active power filters are presented and evaluated. The first method known as the ip-iq technique is based on the fundamental extraction from the load current, whereas the second strategy which is the Direct Control for Active Power (DCAP) method employs power calculation leading to a new definition for active current in case of perturbed source voltages. The comparison is carried on in terms of DC voltage regulation in case of disturbed source voltage. First, both control schemes are analyzed based on the obtained reference currents using simulation results. It is shown that the DCAP is more accurate on the reference current extraction than the ip-iq method. Next, the performance of the DCAP method in terms of current distortion and power factor in presence of a highly perturbed source voltage is demonstrated.