This paper presents the development of a discrete Thyristor Controlled Series Capacitor, TCSC, model using the software DIgSILENT PF. The discrete model is based on switchable inductances. The model was inserted in a practical large network of the Electrical Transmission System in Colombia (ETSC) for automation and planning purposes, as much in steady as transient analysis. The results of the studies with the discrete model were very satisfying and allowed to propose further automated solutions to the needs of expanding the ETSC. .