Space Vector Transients of Three-phase Transformers

Abstract

This paper is devoted to the transient analysis of three-phase transformers by means of the space vector tool. Space vector definition is based on the Clarke transformation, operating in the time domain. Thus, the space vector is better suited to transient analysis when compared with approximate approaches based on the phasor symmetrical-component transformation. Space-vector equivalent circuits are derived for three-phase transformers with Wye and Delta connections. A case study, consisting in the transient due to a capacitor bank insertion, shows that the proposed space-vector approach can clearly evidence the asymmetrical transient behavior of the phase variables in terms of different peak levels and oscillations amplitude.