On-load tap changer digital non-electrical quantity protection method and device

Abstract

The application provides a kind of digital non-electric quantity protection method and device of on-load tap changer, and belongs to the field of transformer protection.The method comprises: obtaining the current oil flow rate instantaneous value of the detection point in the oil reservoir connecting pipe connected with the on-load tap changer to be measured;If the current oil flow rate instantaneous value is greater than the first preset protection action threshold value, a trip signal is sent to the protection relay, so that the protection relay disconnects the circuit breaker;If the current oil flow rate instantaneous value is not greater than the first preset protection action threshold value, the oil flow rate instantaneous value at the next time is obtained, and the oil reservoir connecting pipe unit mass transformer oil kinetic energy change rate is determined based on the current oil flow rate instantaneous value and the oil flow rate instantaneous value at the next time;If the kinetic energy change rate is greater than the second preset protection action threshold value, a trip signal is sent to the protection relay, so that the protection relay disconnects the circuit breaker.The application can improve the reliability of the protection device, and can avoid misoperation, solve the problem of low reliability and misoperation of mechanical gas protection at present.

Images