Comparision of Partial Discharge signal in a Three phase Transformer by UHF, TEV and HFCT sensors

Abstract

Externally produced PD signal is electromagnetically linked with a 3-phase transformer to understand its propagation nature within the transformer windings. Transformer with and without load coupled with this externally generated PD is monitored by Ultra High Frequency (UHF), Transient Earth Voltage (TEV) and High Frequency Current Transformer (HFCT) sensors to compare their performance. PRPD method has also been used to differentiate the discharge magnitude with respect to their phasor positions. Not all the sensors are found to be equally good to identifying the PD pulse magnitude and their phasor positions from their respective principle and geometric locations.