Space Charge Measurement Techniques for Practical Insulation Systems

This article reviews space charge measurements in practical insulation systems, with a focus on ultra-high voltage cable insulation. It describes the history of the author’s involvement in space-charge measurement using the pulsed electroacoustic (PEA) method and deals with the problems assumed in practical insulation systems, such as insufficient measurement sensitivity and acoustic mismatch. Their solutions are also discussed. Examples of measurements on a very thick insulation system, an extra-high voltage cable and joint, and three-dimensional space charge measurements are presented.