Zero-crossing measurements as a tool in the development of high-voltage circuit breakers

High-voltage circuit breakers must be capable of withstanding short-circuit currents determined by the power-supply network in which they are installed. Detailed measurements performed around the zero crossing of the short-circuit current during short-line fault tests allow characteristic variables and curves to be defined, which can then be used to evaluate the breaking capacity of the circuit breaker. The paper describes these characteristic variables, which can be used in conjunction with mechanical design parameters to design circuit breakers for high breaking capacity operation