Modeling and simulation of capacitor voltage transformer transients using PSCAD/EMTDC

This paper describes the modelling of capacitor voltage transformer and simulation of its behaviour during transients using PSCAD/EMTDC. To damp out ferroresonance in CVT few ferroresonance methods have been proposed and used. In this paper, some of the suppressing circuits, series resonance type, parallel resonance type, and electronic type are reviewed. Specifications of these circuits and effects of various parameters on their performances are discussed. During line faults, when the primary voltage collapses, the CVT generates transients due to its energy storage elements. The effect of ferroresonance suppression circuits on the transient response of CVT is also studied and the proposed electronic type ferroresonance circuit is best suited to suppress low voltage transients and high voltage ferroresonance oscillations.