Patent ID: 8970071
Filing Date: 2015-03-03
Classification: H02H,H02J

Abstract:
1. A method for disconnecting a generator from a power system when the generator and the power system connected thereto are non-synchronized, the method comprises the steps of: measuring an electrical parameter of a stator of the generator with a voltage and current measuring device; transmitting an output signal from the voltage and current measuring device to a processing unit, the processing unit: determining a loss of synchronization between the generator and the power system by detecting an amplitude variation of the electrical parameter measured from the generator, wherein a frequency of the amplitude variation is proportional to a rotor angle variation of the generator, the rotor angle variation arising due to the loss of synchronization between the generator and the power system; determining a slope or a frequency of the amplitude variation to determine when a minimum amplitude of the electrical parameter will occur; transmitting a command signal to at least one circuit breaker electrically connected between the generator and the power system for disconnecting the generator from the power system, wherein the command signal is provided to the at least one circuit breaker prior to the minimum amplitude of the electrical parameter being attained; and the at least one circuit breaker disconnecting the generator from the power system when the minimum amplitude of the electrical parameter occurs.