Insights on the Breakdown Characteristics of PPLP Under Different Test Protocols and Temperatures

The electrical breakdown strength of insulation material is very important for the design of a high-temperature superconducting (HTS) cable. This article investigates the breakdown characteristics of polypropylene laminated paper (PPLP) film samples, which are widely used in an HTS cable. Various test conditions, such as different modes of increasing voltage, voltage types, and ambient temperatures, are used. It is found that the breakdown strength of the PPLP film samples varies greatly with the aforementioned experimental conditions. Based on the existing research, the key reasons for the experimental phenomenon are analyzed. The experimental results provide the reference experimental data for the insulation design of the HTS cable.