New single-phase active power filter

A new algorithm for a single-phase active power filter, based on calculation of the real part of the fundamental load current, is proposed in the paper. The algorithm proposed can maintain the input power factor of the mains close to unity and force the mains current to be a sinewave under distorted or nondistorted mains voltage. A prototype is developed and tested to verify its performance. The experimental results show that the algorithm proposed can compensate for the reactive power and suppress the harmonics of the nonlinear load effectively.