A Three-Phase Shunt Active Power Filter for Damping of Harmonic Propagation in Power Distribution Systems

In recent years, harmonic resonance or harmonic propagation between line inductances and shunt capacitors installed for power factor correction, and so on has multiplied voltage and current harmonics in industrial power plants and utility power distribution systems. This paper presents a shunt active power filter to attenuate harmonic propagation resulting from series/parallel resonance between capacitors for power factor correction and line inductors in a power distribution line. The active power filter based on voltage detection is controlled in such a way as to present infinite impedance to the external circuit for the fundamental frequency, and as to exhibit low resistance for harmonic frequencies. When the active filter is installed on the end bus of the feeder, it successfully performs harmonic damping throughout the distribution line. Simulation results clarify that installation of the active filter acting as a harmonic terminator on the end bus of the feeder can damp out harmonic propagation throughout the feeder.