Abstract:
A method of determining a fault parameter of a fault on an AC transmission line 10 of a power distribution system 1 relative to a measurement location 12 of the transmission line 10 comprising: measuring a time-dependent current of the transmission line 10 at the measurement location 12; transmitting a current signal indicative of the measured current to a decision logic section 36, the current signal comprising a plurality of pre-fault current values and a plurality of post-fault current values; determining, by the decision logic section 36, a plurality of phase difference values indicative of respective phase differences between respective pre-fault current values and respective post-fault current values; accumulating the plurality of phase difference values into an accumulated phase difference parameter; obtaining the fault parameter by comparing the accumulated phase difference parameter to a threshold value; and outputting the determined fault parameter.
Abstract:
A power line protection system and method are described with a current meter for monitoring the current in the protected power line and a circuit breaker, with the current meter including a sensor, particularly a fiber optic current sensor, for monitoring a direct current component in the current transmitted and an analyzer for testing the direct current component and for generating a fault signal for the circuit breaker.
Abstract:
A method of determining a fault direction parameter of a fault on an AC transmission line of a power distribution system relative to a measurement location of the transmission line. The method includes measuring a time-dependent AC current of the transmission line at the measurement location to obtain time-domain current data indicative of the measured current, obtaining a time of the fault on the transmission line, identifying first and second times by identifying a periodically re-occurring feature of the current data, such that the fault time is between the first and second times, extracting, from the current data, an offset indicative parameter indicative of a time offset of the current at the fault time and between the first and second times, calculating an offset direction parameter by comparing the offset indicative parameter to a non-offset indicative parameter, and establishing the fault direction parameter based on the offset direction parameter.
Abstract:
A power line protection system and method are described with a current meter for monitoring the current in the protected power line and a circuit breaker, with the current meter including a sensor, particularly a fiber optic current sensor, for monitoring a direct current component in the current transmitted and an analyser for testing the direct current component and for generating a fault signal for the circuit breaker.