Based on the dynamic properties of electrical connector intermittent failure, the model and methods for residual life prediction for electrical connectors are studied in this paper. Firstly, the mechanism of electrical connector intermittent failure is analyzed, and the area enclosed by the contact resistance curve and the fault threshold is defined as the generalized severity of intermittent failure to describe how severe the electrical connector’s intermittent failure is. Then, the Hidden Semi-Markov Model (HSMM) is introduced to build the residual life prediction model of the electrical connector. Further, the evaluation method of using the state and prediction method for residual life are studied. Finally, by carrying out the residual life prediction test, the effectiveness of the residual life prediction method for electrical connectors based on intermittent failure and HSMM is verified.

The intermittent failure re-presentation is the basis of intermittent failure detection and diagnosis of electrical connectors. Recently, the method for intermittent failure re-presentation is applying the whole working stress to the electrical connector. To further shorten the re-present cycle, the research on intermittent failure re-presentation of electrical connector based on accelerated test is carried out in this article. First, the model of electric contact and the intermittent failure mechanism of electrical connector is analyzed, and the frequency of intermittent failure is selected as a signature of intermittent failure re-presentation. Then, the accelerated intermittent failure re-presentation model is constructed based on the reaction theory, and the intermittent failure acceleration factor is given. Subsequently, the distribution of intermittent failure frequency is determined using the method of Anderson–Darling goodness-of-fit test. Finally, taking the rectangular electrical connector as the example, the intermittent failure re-presentation based on accelerated test is implemented, and the intermittent failure frequency is obtained. By comparing the estimated value and the measured value, the validity and applicability of the intermittent failure re-presentation method based on accelerated test is verified.

The intermittent fault of an electrical connector is a latent threat to the reliability of an electromechanical system. For electrical connector intermittent fault diagnosis, an intermittent fault must be reproduced. Reproducing an intermittent fault by a traditional test has a low efficiency and adds some damage to the product, which is not conducive to intermittent fault diagnosis. To further improve the reproduction efficiency of an intermittent fault and reduce the damage, optimal design of a step-stress-accelerated intermittent fault reproduction test is carried out. First, the number of intermittent faults and the degree of damage in the reproduction test are estimated, and reproduction and damage models of an intermittent fault during the step-stress reproduction test are constructed. Then, based on the intermittent fault and damage models, an optimized method based on a genetic algorithm is established. Finally, the validity and applicability of the theoretical model and the optimized method of the step-stress-accelerated test based on a genetic algorithm are verified by comparing data from a contrast test.

The optimization of wind turbine layout is an important step during the design phase of wind farms, which directly influences the overall power performance and the profitability of the wind plants. The spacing distance between the wind turbines, which is often inconsistent in the prevailing wind direction and other directions, is the critical factor of wind turbine array layout optimization. With the considerations of the wind turbines’ safety in operation and the maximum utilization of wind energy resources comprehensively, an elliptic-constrained wind turbine layout optimization model is proposed in this paper. The stochastic optimal algorithm including the constraint checking and random searching processes is established to conduct the iterative calculation. It is proved that the annual energy production of the elliptic-constrained model with non-uniform spacing has increased in comparison with the conventional method. The proposed approach provides an effective engineering solution for improving the space utilization and the power output estimation of the wind farm.