Overvoltages caused by the interruption of small inductive transformer currents

The interruption of small inductive currents can cause high overvoltages, which may overstress the dielectric strength of the equipment. Based on detailed dynamic models for the circuit breaker and the transformer, a variety of parameters which influence these overvoltages is systematically investigated by digital simulation. Such parameters are the circuit breaker properties, the breaking current, the network configuration, and the surge arresters. Furthermore, it is shown that ideal switch models for circuit breakers with preset chopping currents generally will not yield realistic results in multiphase power systems