A New Control Method for Harmonic Compensating and Resonance Damping in Hybrid Filter

Transformerless Shunt Hybrid Active Power Filter (TLS - HAPF), benefiting from its active part undertake almost no fundamental voltage, can be used in medium-voltage power distribution system for harmonic and reactive power compensation. Besides, the TLS-HAPF can also damp out the series/parallel resonance between the existing passive reactive compensation device and line inductance in the power grid. Based on the grid-side harmonic detection and the capacitve current feedback, this paper proposes a novel control strategy for TLS - HAPF to compensate harmonics from nonlinear loads and damp resonance between shunt power-factor-correction capacitors and line inductance simultaneously. Simulation results have confirmed that the filtering performance can be improved by the proposed control strategy.