Time-domain comparisons of two linear models of a thyristor-controlled series capacitor

Abstract

This paper describes a method to construct a linear model of a Thyristor-Controlled Series Capacitor (TCSC) by analyzing its frequency response obtained from time-domain simulations of a detailed model of the device. Such linear model represents the low frequency behavior of the device as needed in power system stability studies. The linear model is validated comparing the time-domain simulations obtained using the original detailed TCSC-model, the developed linear model and a previously obtained linear model. The latter one has been built by disturbing the TCSC with two events and identified with Matlab's System Identification ToolBox from time-domain simulations. By using a linear model, the computing time can be reduced significantly compared to simulations with a detailed TCSC-model, maintaining dominant behavior of the TCSC. All simulations are done with the power system simulation software Simpow.