An active power quality conditioner for reactive power and harmonics compensation

This paper presents a new three-phase active power quality conditioner (APQC) for compensating reactive power and harmonics in distribution systems. The scheme employs a multi-step inverter for reactive power compensation and PWM inverters for harmonic compensation. The inverters are decoupled in such a manner that the high-frequency harmonic compensation module uses inverters of low power rating, while the low-frequency reactive compensation module supports most of the stresses. This decoupled topology is expected to result in a significant reduction in cost and losses associated with active compensators for high-power applications. The principle of operation and the control strategy are described. Simulation results are presented to demonstrate the performance of the proposed system.