Performance evaluation of thyristor based static transfer switch

Industrial customers are becoming more sensitive to variations of utility supply systems due to the growing demand for process controls in automated plants. One option to increase reliability and quality of AC power is to provide sensitive customers with access to two independent power sources. In this paper, a fast thyristor based static transfer switch (STS) is proposed which employs fast voltage-detection and thyristor gating strategies to connect the customer to either of the two sources. Performance of the designed STS system is evaluated using the Electromagnetic Transients for DC (EMTDC). Simulation results are verified by comparing them with experimental results.