SSR analysis with a new analytical model of Thyristor Controlled Series capacitor

This paper presents the use of new model of a Thyristor Controlled Series Capacitor (TCSC) in studies of subsynchronous resonance (SSR). The new analytical model is developed by using frequency response of the non-linear TCSC segment to derive a simplified non-linear state space model, where the frequency of the dominant TCSC complex poles shows linear dependence on the firing angle. The non-linear TCSC model is linearised and linked with the generatorshaft system model and the controller model that also includes a Phase Locked Loop model. The test system selected for the study is the IEEE first benchmark model for SSR studies. The SSR analysis is studied through eigenvalues analysis using MATLAB and the results are validated through PSCAD/EMTDC simulation studies.