PHASE SHIFTING TRANSFORMER WITH LOW ZERO PHASE SEQUENCE IMPEDANCE

摘要

A phase shifting transformer or autotransformer for a three phase power distribution network has a secondary winding comprising a plurality of windings distributed amongst the three core legs such that on each core leg the number of turns of windings generating a flux in the positive direction is substantially e qual to the number of turns of windings generating a flux in the negative direction. Thus, according to the invention, the transformer may be provided with any necessary phase shifting angles between different harmonic sources, with outputs each having a very low zero phase sequence impedance to reduce voltage distortion created by zero phase sequence harmonics.