Discharge and Breakdown Characteristics of Water Ingress Defects of Cold Shrink and Heat Shrink Joints of 10kV Power Cable

The connector of 10kv power cable mainly includes two kinds of cold shrinking and heat shrinking. The requirements for the manufacturing process of the cold shrink joint are low, but the price is high, and the price of the heat shrink joint is cheap but the manufacturing process is high. In Tianjin Electric Power Company, both cold shrink and heat shrink joints are widely used. Due to the harsh operating environment, water ingress is a major problem for cable connectors. To compare the performance of these two joints under water ingress conditions, their partial discharge and breakdown characteristics were compared. Cold-shrink and heat-shrink joints with water-intake defects were prepared. The water-intake defects were simulated with a cotton thread that absorbed moisture. The partial discharge initiation voltage, partial discharge statistical spectrum, breakdown voltage and withstand time of the two defective joints were measured respectively. The research results show that the cold shrink joint shows better performance under the condition that the joint enters water.