Harmonic compensation for nonlinear loads by active power

This paper studies a single phase shunt active power filter (APF) using a bi-directional full-bridge converter with capacitive energy storage to compensate for the harmonics generated by nonlinear loads. The usage of a capacitor as a reactive power source for the APF simplifies the circuitry. The harmonic current reference is obtained by feeding the load current signal into a 50 Hz notch filter. The simple and fast hysteresis control strategy involving only a few analog and logic components makes it attractive for the low power domestic application. The usefulness of the proposed control algorithm is confirmed by simulation as well as by experimental results.