Power electronics active filter with controlled dynamics

Abstract

Present tendencies of evaluation current distortion compensation methods aim to work out such compensator (serial or parallel active filter), which would be able to realize real time compensation. The assumed aim of parallel active filter work is dynamic compensation of differential current which is the difference between load current and reference current. Unfortunately dynamics of every real power electronics current source, being essential part of parallel filter, is limited. Responsible for this is finite inductance of coil at the output of inverter, being part of current source. Proposed idea of increasing dynamics of active filter depends on temporarily changing inductance of this coil. It can be done with using two windings coil, similar to transformer, which second winding is temporarily short-circuited, resulting in decreasing inductance of equivalent circuit of coil so dynamics of current source is higher.