On using the solid state breaker in distribution systems

The paper demonstrates, through the use of electromagnetic transient simulations, the key issues in the application of solid state devices for fault control and protection in the distribution systems. Three types of topologies have been considered, viz. a bus tie breaker, a transfer switch, a fault current limiter, but only two have been discussed in detail; the bus tie breaker is taken to be a special case of the fault current limiter. The control scheme for each topology has been designed and studied, with emphasis on the detection schemes and the responses to various system and load parameters. All simulations have been carried out using the PSCAD/EMTDC program.