A Simplified Control Algorithm for Series Hybrid Active Power Filter

Abstract: Series Hybrid Active Power Filters (SHAPF) have been the main topic of interest for researchers working in the area of power quality, as it combines best features of active power filters (APF) and passive filters. Moreover it is proved to be a cost-effective solution as compared to standalone active and passive filters. Control strategy is a key part of any APF system which decides the compensating characteristics of the filter. For SHAPF many control algorithms have been proposed, they are mainly based on either detecting source current harmonics or load voltage harmonics. Both these methods require decomposition of voltage or current vectors in active and reactive components corresponding to these harmonics. This paper proposes a simplified method of calculating reference for SHAPF. In proposed method the component of voltage vectors corresponding to different parts of active power are only used for deriving reference voltage. This helps avoiding the reactive power calculation and simplifies the control system to a greater extent. Simulation study of SHAPF is done with proposed method and performance of filter is tested in terms of its current harmonic compensation characteristics.

Keywords: active power filters, hybrid active power filter, passive filter, THD.