A Health Evaluation Method of Complex Systems Based on Evidential Reasoning Rule Considering Perturbations

The complex system has been widely applied in aerospace, chemical industry, manufacturing, military equipment and other fields. To ensure its safe and reliable operation, it is necessary for technicians to grasp the health state of the system effectively. However, if there are perturbations in the observation data, the evaluation result may be inaccurate. Besides, the effectiveness of evaluation result can be affected by perturbation, which means that the threshold of perturbation intensity should be determined. To solve these problems, in this paper, a new health evaluation method of complex systems is proposed based on the evidential reasoning (ER) rule by considering perturbations. First, the structure of the evaluation model is constructed. Second, an ER rule-based health evaluation model is proposed, and the idea of perturbation analysis is introduced for the robustness analysis of the model. Third, a parameter optimization model is established, and the upper bound of perturbation intensity is estimated accurately. The threshold can measure the effectiveness of the evaluation result and the anti-perturbation ability of the system in engineering practice. Finally, a case study of the WD615 model diesel engine is conducted to validate the effectiveness of the proposed method.