Partial Discharge In Cable Heads: Causes And Preventive Measures For A Gas Insulation Ring-Network Cabinet

Because of their compact structure, gas insulation ring-network cabinets are commonly used worldwide. However, recently, nearly 100 incidents of burning cable-joints occurred at different locations throughout China. Thanks to the analysis of the failing cable-heads and modern online monitoring technology of partial discharge, which is based on capacitance coupling, important information, which is analyzed in detail in this paper, could be obtained. The evidence, presented in this paper, suggests that during the installation and operation of cable joints, the matching body of cable-boot sleeve and fuse-well pile head needs to be well sealed and grounded to avoid the localization and concentration of the electric field. Furthermore, the information about the partial discharge can be obtained by checking the phase holes of the live display of the ring network cabinet. This way it is possible to enable online monitoring of partial discharge in a ring-network cabinet, which enables early warning and increases the safety of the power system.