Reliability Experiment Of Contact Welding Of Electromagnetic Relay And Life Prediction Method Research

Electromagnetic relays are the main electrical components in various types of system control parts,and their contacts are the direct part to execute system commands.Contacts operating under inductive loads are more susceptible to failure by fusion welding.Analyzing the degradation mode and failure mechanism of contacts under inductive load conditions,and improving the using life of relays under inductive load has become a research focus.This study presents a simulation system,which is utilized to investigate the electrical performance of electromagnetic relay contacts.Through conducting simulation experiments under inductive loads,this study analyzes the degradation modes and failure mechanisms of the contacts,utilizes experimental data as a dataset to predict the service life of the relays.Firstly,in order to obtain the electrical performance parameters of the electromagnetic relay during its movement,an experimental system was designed to simulate a pushrod relay.The system simulates the closing and breaking movement of contacts by driving the push rod repeatedly with an electromagnet;The function of adjusting contact opening distance and overtravel parameters is realized through the mechanical adjustment module;With the designed hardware circuit module,the functions of real-time measurement of electrical performance parameters such as static pressure,contact resistance,rebound energy,and arcing energy are realized;The designed software operation module realizes the functions of collecting,operating,and storing the above electrical performance parameters.Secondly,Multiple sets of controlled experiments were designed to investigate the opening and closing process and failure mechanism of electromagnetic relay contacts under inductive load.Based on the voltage and current waveforms during the opening and closing process of electromagnetic relay contacts under inductive load,combined with the inductive load experimental circuit diagram,a transient mathematical model under inductive load was established to study the physical process of electromagnetic relay opening and closing inductive load;The effects of different inductance values,capacitance values,and mechanical parameters on the contact opening and closing process were analyzed.Subsequently,an electrical life experiment simulating contact fusion welding was designed to analyze the degradation law and mode of electrical performance parameters of the relay during the entire life cycle.The effects of different load types and different opening distance conditions on contact fusion welding were studied.Combined with the microscopic morphology of the contact surface,the failure mechanism of electromagnetic relays under inductive loads was analyzed.Finally,in order to predict the degradation stage of electromagnetic relays,an improved one-dimensional convolutional neural network based on gated recurrent unit is proposed to predict the lifetime of electromagnetic relays.The electrical performance parameters of the electromagnetic relay obtained from the above experiments are taken as a data set,which is randomly divided into a training set,a verification set,and a test set after noise reduction and disruption;An improved one-dimensional convolutional neural network model based on gated recurrent units was constructed and trained on the training set.Through parameter optimization,the learning rate and iteration number conducive to model prediction were obtained.The test set results showed that the model could accurately predict the remaining life of relays.This study can provide a reliable method for testing and evaluating the electrical performance of electromagnetic relay contacts,provide a platform basis for the process improvement and failure mechanism research of contacts,and also provide reference value for the life prediction of relays.