Development of a programmable partial discharge generator for the evaluation of partial discharge measuring devices

Partial discharges (PD) measurement provide valuable information for assessing the condition of the insulation elements in high voltage (HV) electrical grids. During the last three decades, several instruments integrated with specific technical functionalities have been developed in order to perform accurate diagnostics when temporary or monitoring measurements are carried out on-site and on-line. Some electrical utilities, maintenance companies and large electricity consumers have defined technical specifications trying to select the most appropriate PD measuring systems, but in general, no tests are performed to check their capability to perform appropriate and accurate diagnostics. Furthermore, no standard exists to define what type of evaluation should be required to assess the efficacy of this type of instrumentation. In this paper, a reference PD generator developed for the evaluation of the functional features of PD measuring and diagnostic instruments is presented. This PD generator enables the characterization of the technical functionalities of commercial PD instruments in a controlled and homogenous way and without the requirement of apply HV in a test facility. Reference analogue PD time series with superimposed electrical noise time sequences are generated simulating real acquisitions of on-line PD measurements.