Reliability Modeling and Analysis of the Pemanent Magnet Synchronous Motor Considering Ambient Pressure

Permanent magnet synchronous motors (PMSMs) are a cornerstone in the field of advanced engineering, renowned for their exceptional efficiency and power-toweight ratio. Despite their ubiquity, traditional reliability modeling and analysis methods - including Fault Tree Analysis (FTA), Reliability Block Diagram (RBD), Failure Mode and Effects Analysis (FMEA), and Markov chains - often fall short in harmonizing performance with reliability. This discrepancy is starkly apparent in demanding scenarios, such as in aerial electric vehicles at high altitudes, where the thin atmosphere significantly influences PMSM reliability.To surmount this challenge, the paper introduces a belief reliability model. The approach starts by pinpointing torque ripple and torque to current ratio as the key performance metric, followed by the establishment of a Model Predictive Torque Control (MPTC) model. A subsequent thermal model accounts for variations in ambient pressure and environmental temperature. Furthermore, a performance degradation model that captures the impact of ambient conditions on flux deterioration is presented. Culminating in the analysis of uncertainties, a reliability measurement framework for the motor system is constructed. This work offers an strategy for the reliability modeling of permanent magnet synchronous motors, with particular consideration of ambient pressure factors, and demonstrates the model's efficacy through a case study focused on reliability analysis.