GPS Based Synchronous Data Acquisition for Double-ended Partial Discharge Measurement

Abstract

The subject of partial discharge detection and localisation has been of considerable interest to electric power utility engineers and researchers for many years. Partial discharge activities damage the insulations of cables and will produce unexpected power outages, asset damages, and even injury or death. Research on the double-ended measurement of partial discharge is presented. The proposed method features highly accurate time tagging, high speed data acquisition, low cost and is based on the studies of the characteristics of partial discharge The proposed measurement system has two separate testing ends sharing the same architecture. Each end consists of a GPS module, from where an accurate 1 PPS and the UTC information are provided, an ADC circuit, which digitises analogue PD signals and an FPGA based CPU, where the GPS time information and ADC data are collected and processed to obtain the time stamps of PD signal. The developed double-ended measurement system has been tested by utilising digital and analogue inputs during emulation. The digital emulation aims to check the performance of the configuration of the FPGA based CPU and the analogue emulation tests the comprehensive behaviours of the overall measurement system. The developed system performs well for the accurate time tagging and fast data acquisition. The factors, which might account for timing and digitising error in the current system, have been discussed and the appropriate solutions have been provided.