PARTIAL DISCHARGE DETECTION DEVICE FOR ELECTRIC APPLIANCE

PURPOSE:To surely and speedily detect partial discharge generated in a coil without being influenced by noise, with a relatively simple constitution. CONSTITUTION:A current detecting means 4 is provided corresponding to each phase of coil 1 of a transformer, and the detection signal is outputted to a phase adjusting circuit 5. In the circuit 5 paired detection signals are integrated so that they are adjusted to have a same phase to cancel the signal components. The signal components as well as noise signal components are to be eliminated almost so that in the case where a signal by partial discharge is included only the signal remains. In a processing display circuit 6, the output signal level from the circuit 5 is compared with a reference level and thereby generation of partial discharge can be detected.