CONTROL STRATEGY OF ACTIVE FILTER USINGCOORDINATION BETWEEN PROPORTIONAL-INTEGRALMULTI-RESONANT-TYPE REPETITIVE CONTROLAND COMPOSITE OBSERVER

Abstract

This paper presents a control strategy to enhance the operation of an active filter (AF). First,
the high-order harmonic components of the current are accurately extracted using a composite
observer. Then, a proportional-integral multi-resonant-type repetitive control (PIMR-RC) is
applied to control the current harmonics generated by the active filter to follow the current
harmonics caused by the nonlinear loads. Simulation using PSIM software for the active filter was
performed to verify the feasibility of the proposed control strategy.