Research On Optimization Design And Statistical Analysis Of Cyclic Stress Accelerated Degradation Test For Electrical Connector

As a basic component for realizing the transmission and control of electrical signals and the electrical connection between devices,electrical connectors have been widely used in aerospace,electronic communications and automotive fields.There are a large number of different types of electrical connectors in a complex equipment system.If one electrical connector fails,the entire system may fail.It can be seen that the reliability of the electrical connector directly affects the reliability level of the equipment system.Therefore,accurately assessing the reliability level of electrical connectors is of great value to the reliability research and design of model equipment.At present,constant stress accelerated degradation test methods are often used for reliability assessment of basic components such as electrical connectors.However,due to the limitations of test equipment,the actual test profile of electrical connectors is cyclic stress instead of constant stress.Therefore,the existing theoretical method of constant stress accelerated degradation test cannot effectively evaluate the reliability of the electrical connector under the actual test profile.In view of this problem,this paper studies the cyclic stress accelerated degradation test method.The research object is Y1 IP-1419 type electrical connector.In the first chapter,the background of this research are discussed detailedly.It summarizes and summarizes the research status of cyclic stress accelerated degradation test from the aspects of accelerated degradation test technology,optimized design and statistical analysis methods.Based on the analysis of the current research deficiencies,the research content of this paper is given.The second chapter first analyzes the failure mechanism of the electrical connector in the storage environment,discusses the response of the electrical connector's contact performance to cyclic stress,and reveals the effects of various parameters of the temperature cyclic stress on the contact performance of the electrical connector.A model of electrical connector performance degradation considering the temperature rise and fall rate,cycle period,and number of cycles was established.Finally,based on the analysis of the structural characteristics of the electrical connector,a life distribution model of electrical connector contact degradation failure was constructed.The third chapter studies the optimization design method of the cyclic stress accelerated degradation test scheme of the electrical connector.Based on the accelerated degradation model,a mathematical model for the optimized design of the electrical connector temperature cyclic stress accelerated degradation test is established.The temperature cycling stress accelerated degradation test scheme for electrical connectors is optimized.The optimization criterion is that the asymptotic variance of the reliability estimate at the normal stress level is the smallest,and the optimization variables are the minimum stress level,the temperature rise and fall rate and the number of cycles.Finally,a cyclic stress accelerated degradation adjustment test plan was developed based on the actual engineering.The fourth chapter proposes a simulation evaluation method of cyclic stress accelerated degradation test scheme for electrical connectors based on Monte Carlo simulation.The cyclic stress accelerated degradation test scheme is simulated and evaluated.The evaluation results verify the cyclic stress accelerated degradation from the aspects of accuracy and robustness.The correctness of the test plan optimization design method and the feasibility of adjusting the test plan.The fifth chapter carried out the cyclic stress accelerated degradation test.According to the accelerated degradation test data of the electrical connector,the maximum likelihood estimation method was used to calculate the estimated values of the cyclic stress accelerated degradation model parameters of the electrical connector.Reliability levels were evaluated at normal stress levels.Finally,it summarizes the work of the whole paper and prospects and suggestions for the next research of the subject are put forward.