Detection of partial discharges in enclosed HV switchgear - requires vibration sensor with signal frequency analysed and inspected for discharge patterns when voltage is above threshold

摘要

In a procedure for detecting discharges within enclosed switchgear, a vibration sensor is used to monitor mechanical movement of components, the sensor signal being frequency analysed and then inspected for signs of a discharge having occurred. An indication is only given if the value of the voltage at the switchgear exceeds a certain threshold. Therefore the vibration sensor signal is only used when the voltage is above this threshold. Alternatively, the sensor is used continuously as input to the frequency analyser, but a blocking element only allows comparison of the result with known discharge patterns for voltages above the threshold. ADVANTAGE- High reliability; system only active for relevant switchgear voltages.