The Investigation Of The Effects Of Electrical Joint Compound On The Performance Of Power Connectors Under Atmospheric Environment

As an important part of power system,power connector plays a vital role.However,with the application environment of power connectors is becoming worse and worse,the environmental impact on the power connectors is gradually serious.The safety operation of power connector is worried.Electrical joint compound is a product that can protect power connector from terrible conditions and stabilize the contact resistance.There are many kinds of electrical joint compound in the market,but neither their protective mechanism nor the protection ability is clear.In this paper,a bolt type power connector was selected as test sample.The performance and protective mechanism of some types of electrical joint compounds in protecting power connectors from atmospheric environment were studied.A method for establishing the model of the accelerated life of the connector was discussed,and the accelerated life was compared.Since power connectors have high reliability and long life,a proper accelerated test method must be adopted.According to the failure characteristics of bolt type connectors,in this paper,we carried on the experiments from two aspects:One is to reduce the bolt torque,so that the connector is more sensitive to environmental factors;the other is to change the environmental stress levels,speeding up the influence rate of environmental factors on the connectors.This thesis mainly focuses on three environmental factors,temperature,humidity and salt spray and studied protection mechanism and performance of electrical joint compound.On the basis of reducing the torque of the bolts,the accelerated experimental method was designed for these three kinds of environments.And according to the experimental results of the temperature environment,the contact resistance curve was fitted as time.After selecting the failure threshold,the accelerated life model of the connector is established according to the life data obtained from contact resistance fitting curves.High temperature will increase the oxidation rate of the contacts,so as to accelerate the contact failure;High humidity will make water film to adsorb on the contact surface,it is easy to form the galvanic corrosion on contacts;Chlorine ion contained in the.salt-fog will destroy the metal oxide film,so that the metal is directly exposed to the outside world and is corroded and destroyed.Experimental results showed that electrical joint compound can supply a good protective function on the contact surface of the power connectors.But different compounds showed different performances.The accelerated experiment by reducing the torque of the bolt and increasing the environmental stress is feasible.And the accelerated life of the connector can be predicted quantitatively by setting different stress.