Measuring system for partial discharge

Measuring of the partial discharge (PD) parameters of the insulating systems is very important. The prompt insulating system estimation and its remaining life time give the great savings. The new, complex PD measuring methods are now developed in the world because conventional methods do not give valid information of the insulating system conditions. The goal of this paper is to show one of the new approaches in the data acquisition about PD and the measuring system performance. The measuring system consist of a few blocks: measuring bridge, multichannel analyzer (ND60), oscilloscope and personal computer (PC). The components of the measuring bridge are corresponding filters and charge calibrators. For the signal analyzer of PD we apply the ND60 (made by Nuclear Data Inc. USA). The ND60 is a multichannel pulse analyzer, including built-in charge preamplifier, amplifier, 50MHZ analog to digital converter (ADC), monitor, 2048 channel memory and serial and parallel I/O interface. ND60 realize two data acquisition modes: pulse height analysis (amplitude analysis) and multichannel scaling (time analysis). The voltage impulse of PD represents the input in the charge amplifier (the impulse integrator-signal output is proportional to the charge transfer). Analysis of signal on a time basis enables the acquisition of data (input signal) vs. arrival time. With an ability of a usage the external sweep trigger it is possible to analyze the PD as a function of phase of input voltage (power source). The PC enables the measuring system management, data acquisition from the memory of the ND60 and its processing according to the certain algorithms.