A possible application of the non-uniform electric field measurement using Pockels effect in GIS (gas insulated switchgear)

Summary form only given, as follows. In this paper, a novel optical measuring system for the measuring of non-uniform electric field was proposed. The first feasibility investigation on the probe sensor, based on the Pockels cell, has been performed to measure the variation of the electric field due to the corona discharges. The aim of this work is to develop a chip type electric field sensor which would be applicable to the EHV power apparatus in the future. For this purpose, optical measurement system was constructed and test cells and probe sensor were designed and fabricated. The electric field distorted by the discharge was detected through proposed optical measuring system based on the Pockels effect at GIS. In order to produce distorted electric field, corona discharge was generated from needle-plane electrode on the conductor at GIS in air and detected by optical measuring system. This optical system is constructed by He-Ne laser, single mode optical fiber, 2/spl times/2 50/50 beam splitter, LiNbO/sub 3/, Pockels cell, photodetector and PC. In this system, output signals of Pockels sensor is measured by the digital oscilloscope and transferred to the PC for recording and statistical processing. Through this paper, promising possibilities of proto-type optical measuring system were evinced.