A novel modeling approach of SVC for three-phase transient stability simulator

Transient stability analysis requires appropriate models of FACTS devices. This paper describes a new Static VAR Compensator (SVC) model for transient stability simulations. The main attention is paid to the model of thyristorcontrolled reactor (TCR) as part of SVC. In the standard model, the influence of PLL is neglected for transient stability analysis. It is shown that the value of the TCR phase-to-phase susceptance differs from that given by the control system for unbalanced disturbances. These effects are associated with a firing pulses error that is due to the PLL response to the phase-to-phase voltage change. The proposed model allows to take into account these effects. In addition, it is shown that these phenomena can be reproduced only in a three-phase model for transient stability simulations. Validation of the model was done by comparing simulated results with an accurate electromagnetic transients program (EMTP) model.