Digital measurement system for generator on-line PD monitoring system

Partial discharge (PD) testing is an effective means to find the internal insulation faults of generators and the acquired signal is the basis for further signal processing and insulation diagnosis. This paper presents the basic scheme of generator PD on-line detection and processing principle of data acquisition flow. A computer based system for digital acquisition, storage of the PD signal is described, the FFT analysis, FIR filter and other processing methods are illustrated. The methods of assessment for the digital measurement system are also illustrated.