Combination of frequency spectrum analysis and partial discharge pattern recording

The phase resolved partial discharge detection technique (or 'pd pattern recording technique') is applicable to field measurements, particularly if combined with disturbance rejection techniques and non-conventional pick-up circuits. Electromagnetic disturbances can be eliminated by filtering in the time domain (impulse noise gating) and/or in the frequency domain (down-mixing). The pd patterns not only help to identify the defect type but also serve to evaluate the efficiency of the disturbance rejection procedure.< >