The electrical connectors are a significant component of the system and system performance is directly influenced by the ability of electrical connectors to conduct required signals and current throughout the designed life. The overall performance of an electrical connector can be gauged with respect to its structural, thermal and electrical performances which in turn are interrelated. Therefore, designing an electrical connector for a given application is a challenging task and the need for its miniaturization in order to be accommodated in the system further increases this challenge. Also, the procedure required for connectors’ design and development and their testing in order to determine the reliability before installing in an application is time consuming and labor intensive process. In this work, a systematic approach to the parametric modelling and design optimization of electrical connectors using structural and coupled structuralthermal-electric finite element method (FEM) along with the methodology using data driven statistical process for prognosis of the state of health (SoH) and lifetime of connectors using the data of contact resistance development in short term tests is introduced. In this way, the time required from design conception of electrical connectors to their installation in a system after confirming the reliability is significantly scaled down.

For design optimization, a 13.6 mm silver coated round connector with brass as base material is used as a reference connector and multiple CAD models are generated using parametric modelling method through variation of dimensions of reference connector within prescribed limits. The structural analysis of various models is conducted using structural FEM simulation and contact force and contact area between receptacle and pin are determined. The connector model having maximum contact area and contact force within acceptable limits is identified as structurally optimal and is further analyzed for thermal-electrical performance using coupled structural-thermal-electric FEM simulation. The electrical resistance and joule heating of the optimized connector model is compared with the reference connector. In order to validate the simulation model, the simulated electrical resistance and joule heating in reference connector is compared with experimental results. For confirming the conclusions derived from the proposed approach and it’s applicability to different connectors, a smaller connector of 2.5 mm size is analyzed using the similar procedure and the simulation results are compared with experimental results. The tribological performance of connector is investigated by simulating the rough surface deformation using FEM with a view to determine the real contact area for given contacting conditions. The surface roughness is modelled in the form of triangular ribs using core roughness RK obtained from bearing area curve and the average groove width RSM. The simulation results are indirectly verified using measured electrical contact resistance and the correlation between contact resistance, contact force and the effective electrical contact area is established.

In accelerated life testing (ALT) of connectors subjected to thermal cycling, irrespective of their design, a strong correlation between the contact resistance development from initial period and number of failures in later stages of tests is observed. This correlation is exploited and a statistical procedure utilizing the contact resistance data from initial short term test for prognosis of connector reliability is introduced. Through this method, the data of 10 to 50 days of test can be applied to predict the results up to 2 years with a good precision. In this way, the proposed work introduces an adequately reliable and promising approach to significantly shorten the time required for designing and testing of electrical connectors.