Time-Domain Current Information Based Faulty Phase Detection in Thyristor Controlled Series Compensated Transmission System

Identification of fault in Thyristor Controlled Series Compensated (TCSC) compensated transmission system is challenging due to the nonlinear operation of the bidirectional thyristor, and Metal Oxide Varistor (MOV). Protection algorithms which use the current signature based on time or frequency domain analysis malfunction to propagate accurate information about fault condition. It can also happen that nonfaulty phases may detected as a faulty fault due to the replicated unbalance condition in the healthy phases. But such an issue can be resolved by extracting the fault generated components from three phases. In this way identification of accurate faulty phase will be easier. The frequency information in time domain revealed the presence of fault generated components. The same procedure is applied in this work to perform the fault identification task in TCSC line. The Empirical Mode Decomposition (EMD) incorporated with Teager Energy Operator (TEO) is used to extract and estimate the energy index of the most significant mode. Using the energy index fault identification process is accomplished in TCSC line. Results for different cases are provided which are obtained from the simulation of single and double circuit TCSC line. Both the lines are simulated using EMTDC/PSCAD software.