Robust Design Of Life Cycle For High-voltage Power Modules Based On Isight

As a power supply used in spacecrafts, the quality and the reliability of power modules face enormous challenges. Robust design method is one of effective way to improve its quality. In the present, most of the robust design was conducted only for the initial quality. However, reliability of an electronic system will be affected by performance of components its used, environment conditions it works inside, working hours and other factors. Therefore reliability index is dynamic and time-varying. Based on considerable research of reliability analysis and robust design in engineering application at home and abroad, the total lifecycle robust design method of high-voltage power modules is studied. The main contents are as follows:Firstly, the critical quality characteristics are identified via the analysis of failure mode and effects and power supply technical index. Then, the thermoelectrical model of the power supply is established through Isight. Sensitivity analysis based on the orthogonal experiment is completed using the above model. The key component causing the quality fluctuation is determined. After that, degradation models of the key components is provided through analyzing the literatures.Secondly, approximate modeling method for the power supply based on Isight is executed. Among them, the design variables are the key components’ parameters and the objective function are the critical quality characteristics. Then, the approximate model having appropriate precision is chose through the error analysis. Thus the efficiency of the simulation calculation is improved. After that, the time-variant reliability of power supply is analyzed through the degradation models of the key components and Monte Carlo simulation technique. The foundation for life-cycle optimization is provided.Finally, the cost-tolerance model and the cost-quality model of high-voltage power modules were derived. Then the multi-objective optimization mode of total lifecycle is established by the theory of reliability analysis and robust design. And the Pareto solution of parameter and tolerance is acquired base on the above model. The comparison between Pareto solution and initial design is completed by simulation and the validity of the method is verified.