The SFR-APF series Active Harmonic Filter is a new type of power quality improvement products for the harmonic distortion in the circuit. With the advantage of the Fast Fourier Transform(FFT) and 3-Level technology, the SFR-APF Active Harmonic Filter has the 97% efficiency for harmonic filtering and dynamic reative power compensation. The Rack-mounted module is widely used in power quality cabinets with variety outter sizes. The SFR-APF has complied with the IEEE-519 standard and CE certificates, adapt to the global market.