Modified Two-core Phase-shifting Transformer Based on the Classical «Delta Connection» Scheme

Abstract

Nowadays, in joined power systems increases the role and significance of phaseshifting devices, which are used in the quality of FACTS-controllers (Flexible Alternative Current Transmission System), allowing solving various problems of modes management in a complex-closed inhomogeneous network. A modified version of the two-transformer circuit phase-adjusting device, built based on the classical single-transformer scheme «Delta Connection» has been studied in the paper. The proposed device’s topology differs from the classical of single-transformer one so that the control coil is supplied by a lower voltage than phase level, which in turn makes it possible to use it in high rated voltage networks. A mathematical model of the device, which describes the change of parameters of operation mode of phase-shifting transformer under the adjusting of the phase-shifting angle, has been provided. The achieved results can be used for comparative analysis when determining the technical and economic efficiency in the deal of further development of phase rotating devices of transformer type.