Study of Power Transfer in Variable Frequency Transformer

EasyChair Preprint 2564

Abstract

Variable frequency transformer (VFT) integrate the basic principles of rotary transformer and phase shifting transformer to control active power transfer between the two electric network. The active power transfer control concepts, design, and transient staging of the VFT have been deliberate in brief and are reported in the literature. However, reactive power flow through the VFT has not been knowing so far. In the live installations, in order to meet the VFT internal reactive current needed (magnetizing), switched capacitor banks are being used on the two sides of the VFT. These switched capacitor banks are outside to deal with uncontrolled reactive power interchange that can happen between the two networks through the VFT. This may attain desired power factor operation, but cannot avert the undesired reactive power exchange. These paper represent the detailed study on reactive flow through the VFT. The paper also proposes a new VFT configuration (with integrated partially-rated series voltage compensation strategy) to achieve a total control over reactive power flow. Thereby, the proposed design can achieve the bidirectional and decoupled active and reactive power flow through VFT.

Keyphrases: Asynchronous grid interconnections, Variable Frequency Transformer (VFT), decoupled active-reactive powers transfer, reactive power exchange

@booklet{EasyChair:2564,
  author    = {Veena Singh},
  title     = {Study of  Power Transfer in Variable Frequency Transformer},
  howpublished = {EasyChair Preprint 2564},
  year      = {EasyChair, 2020}}