Experimental Research On Corrosion And Protection Of Some Key Components Of High-Voltage Isolation Switch

High-voltage isolating switch is one of the most widely used high voltage electrical equipment in power system.However,in recent years,faults and accidents,especially in corrosion,occurred frequently.According to the demand to optimize cost from the source and strengthen the supervision of metal,this paper was written based on "Research of Open High-voltage Isolating Switch" project of State Grid.Some experimental investigations on corrosion and protection of key parts of high voltage isolating switch,such as transmission rods,joint bearings,bearing blocks,conductive contacts,have been carried out,in order to provide necessary technical support for manufacturing,protection design,inspection,installation and maintenance of outdoor isolating switch.The research contents of this paper are as follows:(1)Described the background and significance of the research,analyzed the outdoor high-voltage isolating switch and its common faults,especially the corrosion problems,described the theory and experimental research methods of atmospheric corrosion of metals and their protection,and reviewed the research status of corrosion and protection of isolating switch.(2)Carried out neutral salt spray test and acid salt spray test of key parts of a certain type of high-voltage isolating switch,in order to exposure and find problems of in corrosion of high-voltage isolating switch,and provide a reference basis for subsequent experiments.In addition,analyzed these problems and put forward improvement measures in the end.(3)Aimed at the damage of the galvanized layer of the joint bearings of outdoor isolating switch caused by atmospheric corrosion and scratch during transportation and installation,put forward different rehabilitation measures.Then compared these measures through the salt spray/dry/wet alternate test,and analyzed results of the test.In the end drew a conclusion of that which one is the feasible and reliable and simple rehabilitation measure on site.(4)Aimed at the material selection and anti-corrosion measure of transmission rods of isolating switch,put forward Q235 and Q235NH as material used in isolating switch and a variety of anti-corrosion measures,then tested and verified these ideas through experiments.(5)Aimed at the abnormal heating problems of electric contact in high-voltage isolation switch,put forward a method of "online" salt spray test on the electric contact,and designed a set of "online" salt spray test device,and then studied the change trend of the loop resistance with the opening and closing times when isolating switch "offline" and the change trend of the loop resistance with the time of salt spray when isolating switch "online".(6)Summarized the current work and results,and prospected for the future work.