Method for estimating an electrical operating time of a circuit breaker using current feedback

摘要

In aspects, the present invention discloses a method of determining an electrical operating time of a circuit breaker (140) in a multiphase electrical system having a subsystem (160) connectable to a power source (110) through a circuit breaker (140) operated by a controller (130). The controller is connected to a current transformer (120, 150) for measuring current of the subsystem in a one phase. The method comprises monitoring the current of the subsystem in the one phase, determining a first rate of change from the monitored current in the one phase, detecting an instance of switching in an another phase based on the first rate of change, and determining an electrical operating time of the circuit breaker in the another phase based on the detected instance of switching and an instance at which a command for switching in the another phase was provided to the circuit breaker.