SVC model with representation of MV Bus and associated protections

This paper describes an SVC model including representation of the MV Bus and associated step-up transformer. In addition to providing insight on the inner workings of an SVC, such modeling allows representation of protective functions such as MV bus voltage limiter and TCR current limiter. The model is appropriate for simulations ranging from the short-term electromechanical dynamics to the extended-term dynamics of voltage instability, and from the severe undervoltages in voltage collapse simulations to the overvoltages in rejection studies. Utilizing a recent installation of two +300/-265 Mvar SVCs in the Oncor system as an example, guidance is provided for the selection of appropriate model parameters, including adjustments to be made when modeling two identical SVCs at the same station. Finally, with aid from time simulation results, the model response is illustrated, and agreement with calculations made during parameter derivation is confirmed.