Partial discharge is an important cause of insulation failure of electrical equipment. A long time partialdischarge will reduce the insulation performance of the equipment. Considering the occurrence of the electricalequipment’s partial discharge fault is closely related to the electric field distribution of the dielectric. In order tosolve the problem that partial discharge is easy to occur during the test process of the parts of the 12kV ring networkcabinet

the Ansys software is used to simulate the electrostatic field of the original model of the fuse tube

and theproblem area of the large and uneven distribution of the electric field-the epoxy resin shell between the right side ofthe end cover and the metal side plate is extracted. Partial discharge is very likely in this area. By using the theory ofelectrostatic field

the optimization of local spraying of zinc from the surface of the epoxy shell to a local zinc ground-ing and convex platform is proposed on the premise of small changes in the shell of epoxy resin in the fuse cartridge.Through the simulation of the electrostatic field

the maximum electric field intensity of the problem area before andafter the optimization is reduced from 26.9kV/mm to 14kV/mm and finally to 2.7kV/mm. The correctness of the fi-nal local spray zinc grounding and convex platform scheme is theoretically verified. Finally

the partial discharge testof the fuse tube samples of different schemes is carried out. The results show that the area of the actual partial dis-charge fault in the fuse tube is consistent with the problem area of the simulation of the electrostatic field

and the ra-tionality of the simulation analysis of the partial discharge using the electrostatic field is verified

and the partial dis-charge of the fuse tube after the optimization is finally optimized. The feasibility of the optimized scheme has alsobeen verified in engineering practice.