航天继电器失效机理与寿命预测方法的分析word格式论文.docxVIP

优秀毕业论文 精品参考文献资料 Abstract In recent years, with the increasing demands on the reliability of aerospace systems, as one of the components which have the highest failure rate, the life and reliability of the aerospace relay needs to be urgently improved. Therefore, research on failure mechanism and life prediction method for aerospace relays has significant theoretical and practical value. From the angle of arc erosion and material transformation, the surface morphology of delay contact is observed in the essay. And with the degradation trend of sensitive parameters monitored in the life test, the failure mechanism and failure mode of aerospace relay are analyzed. Through the life test for aerospace relay with resistance, capacitive and inductive load, the failure mechanism and failure mode are analyzed respectively, and the effects of different load conditions are compared. Based on the data of sensitive parameters, the failure mechanism of aerospace relay is discriminated by principal component analysis and Mahalanobis distance discrimination method respectively. In this essay, the predictive variable and failure threshold under different failure modes are determined by observing the failure mechanism analysis and the degradation trends of sensitive parameters. The testing data based on sensitive parameters in put forward and degradation model of aerospace relay is established. In order to improve the accuracy of degradation models, the methods of outliers eliminating, smoothing process and wavelet transformation are used for denoising of the sensitive data. The actual life and predictive life in the degradation model of failure relay are compared to validate the accuracy of the degradation models. In this essay, the reliability and life test system of aerospace relay is designed and developed. The whole system consists of hardware system, lower computer software system and upper computer system. The real-time acquisition of contact voltage, contact current, coil c