Study on a Novel Hybrid Active Power Filter Applied to a High-Voltage Grid

A novel hybrid active power filter (HAPF) applied to a high-voltage grid is proposed. The passive filter of this topology can be used for reactive power compensation as well as for harmonic mitigation caused by the nonlinear load. The active power filter, which is shunted to a fundamental resonance circuit, is connected in series with a matching transformer, thus forming the injection-type hybrid active power filter. Because of this advantage, it is effective to be used in the high-voltage distribution grid. The basic principle of this topology is introduced particularly. Then, the steady compensation characteristic and the resonance-damping characteristic of this system are analyzed in detail. The principle about the designing method of HAPF is proposed. A HAPF prototype with the proposed designing method was built, and installed in a copper plan in Southern China. Experimental and application results prove that the proposed HAPF is good in harmonics elimination, reactive power compensation, and reliability.