Spatially resolved measurements of electric field distributions in gas-insulated high voltage components using a CO(2) laser probe beam.

A new optical method for spatially resolved measurements of high electric field strengths in gas-insulated high voltage components is presented. The method utilizes the parity mixing phenomenon and the Stark effect in a trace gas (NH(3)) added to the insulating gas (SF(6)). The change in the optical properties of the trace gas when exposed to the electric field is probed using a CO(2) laser. Measurements on different electric field distributions have been made and compared to theoretical calculations using the finite element method. The use of the Stark effect is briefly reviewed, and methods for extending the range of measurements and further increasing the resolution are discussed.