Stability analysis of active filter using series-resonant high-frequency AC-linked DC-AC converter

This paper deals with stability analysis of an active filter using a series-resonant high-frequency AC-linked DC-AC converter, which compensates reactive current and harmonic current in the utility line generated from the electric and electronic apparatus of home appliances. First, an equivalent circuit which describes the macroscopic behavior of this converter is derived. Then, a method for the real-time output current control of the converter to compensate the reactive power is realized based on the equivalent circuit of converter. The stability of the active filter is analysed by Nyquist loci. The usefulness of the proposed control algorithm is confirmed by analytical and experimental results.