A Novel Shunt Single-Phase Active Power Filter for High Voltage Application

In this paper, a novel shunt single-phase active power filter is proposed for high voltage application, which is based on the harmonic impedance control of a special linear transformer with multiple secondary windings. The transformer's primary winding is shunted with harmonic-producing loads, while its multiple secondary windings are connected with inverters. The transformer's secondary currents that produced by the inverters are proportional to its primary harmonic current. When the harmonic current compensation condition is satisfied, the transformer can really exhibit nearly zero impedance to harmonic current and primary self-impedance to fundamental current. Thus, the harmonic currents in high voltage power distribution systems can be led to flow into the transformer branch. The validity of the novel principle and excellent filtering characteristics are verified by the experimental results