A voltage regulator/conditioner based on a hybrid transformer with matrix converter

Abstract

This paper deals with a voltage regulator based on a hybrid transformer with matrix converter realizing an electrical coupling in the hybrid transformer unit. The parameters of electrical energy such as voltage amplitude are very important, particularly from the viewpoint of the final consumer and sensitive loads connected to the grid. Furthermore, a hybrid transformer using matrix converter can be used for power flow control and for transient stability improvement in AC transmission systems. Active power flow and voltage magnitude in transmission lines can be varied using a conventional or thyristor controlled regulators. However, the control parameters can be executed only in steps depending on the taps available in the transformer. An approach for obtaining continuous control of the voltage magnitude and phase shift using a conventional transformer with two windings and a pulse width modulated matrix converter is presented in this paper. The operating principles and steady state properties are discussed. Detailed computer simulation results are presented in the paper. Furthermore, experimental test results obtained from a three-phase 3 kVA laboratory model with passive load are also presented.