State space simulation and accurate determination of fundamental impedance characteristics of a TCSC

A new method of derivation of the fundamental impedance characteristics of a thyristor controlled series compensator (TCSC) is discussed in this paper. This derivation uses the state space model of a fixed capacitor-thyristor controlled reactor (FC-TCR) circuit. It is assumed that the FC-TCR circuit is supplied by a constant AC current source. The fundamental TCSC characteristics are then derived by the step-by-step solution of state equation. In this derivation we present two methods-one assuming that the TCR reactor has infinite Q-factor and the other assuming that it has finite Q-factor. The derived fundamental characteristics are verified through digital computer simulation studies and some experimental results are also presented.