The state-of-the-art of active filters for power conditioning

Unlike traditional passive filters, active filters for power conditioning have multiple functions such as harmonic filtering/damping/isolation/termination, load balancing, reactive-power control for power factor correction and voltage regulation, voltage-flicker reduction, or their combinations. Significant cost reductions in both power semiconductor devices and signal-processing devices have inspired many manufactures in Japan, Europe and the United States to put active filters on the market. This paper deals with active filters for power conditioning, and specifically hybrid active filters for harmonic filtering of three-phase diode rectifiers