A quasi-instantaneous reactive power compensator for unbalanced and non-sinusoidal three-phase systems

This paper discusses the merits and demerits of the instantaneous reactive power compensator, and proposes a new quasi-instantaneous reactive power compensator which is suitable for unbalanced and nonsinusoidal three-phase power systems. It compensates individual-phase reactive currents quasi-instantaneously, being different from the instantaneous reactive power compensator or a conventional reactive power compensator based on the average value concept. The basic principle of the proposed quasi-instantaneous reactive power compensator is discussed in detail. Simulation results demonstrate the novelty of the proposed reactive power compensator where the power factor of each phase becomes unity on the source side, but the source currents remain unbalanced.