Electro-thermal Coupling Simulation And Virtual Reliability Evaluation For Aerospace High-voltage Power Modules

The function and composition of modern electronic equipment is morecomplex, at the same time reliability promotes quickly. In order to improve thereliability of electronic equipment, a lot of time and money were used to test, te st,data collection and product changes, however the result is not satisfactory. Virtualreliability evaluation technology is in the simulation software environment, andthrough digital prototype and physical model, the product is expected to withstandthe working environment of stress associated with the process of fault occurrence,development, and quantitative calculation of product all kinds of potential failuretime, pointed out weak links, in order to take corresponding measures to improvethe reliability of the design level.Due to that the price is expensive, working environment is very difficult toexperiment, design margin is big and service life is long, the reliability of thetraditional design method is not applicable. However virtual reliability evaluationtechnology makes up for the insufficient. Therefore, research on virtual reliabilityevaluation technology of space power module is very urgent.With the density of energy conversion of power module is getting larger, theimpact between thermal and electrical physical phenomenon in power module is sohuge that the data accuracy which is calculated independently in used circuitanalysis or thermal analysis method can’t meet the design requirements. Consideringthe worse temperature environment in the space, the research of the electro-thermalcoupling simulation method in power module is very necessary.This paper uses the method based on manual for power module reliabilityanalyzing and estimating, including reliability prediction, and the failure mode andeffect analysis, fault tree analysis and so on. Macroscopic angle is given onreliability of the components and products.Then this paper compares two common ways used in electro-thermal couplingsimulation modeling, and builds the model of the power module by Saber softwarewhich is verified by experiments. The next step is building the thermal model byANSYS, and confirming the results by thermal imager. Finally, the ISight softwareallies the thermal and elctrical models, and establishes the coupled electro-thermalmodel of the power module, which is verified by experiments and analyzed themodeling error.Finally, this paper uses a method based on the physics of failure to analysis andpredict the reliability of power module. Both the failure mechanism and thereliability are analysed and predicted for the electric-heat stress of typicalcomponents, the thermal stress of typical joints and plated through hole, analyzingand explaining their typical failure physical model.