Sensitivity Analysis and Uncertainty Quantification of Thermal Behavior for Permanent Magnet Synchronous Machines

Uncertainty is a key issue in thermal analysis and management for permanent magnet (PM) synchronous machines (PMSMs) and always occurs in both conduction and convection heat transfers. However, this issue has not been evaluated thoroughly. Therefore, this paper presents a comprehensive sensitivity analysis with uncertainty quantification, and the influences of more than 20 uncertain factors on temperature rises of winding and PM are evaluated. The investigated uncertainties include the convection coefficients under different cooling methods, the main machine losses, the interface gaps, and the materials' thermal conductivities, where a 3-kW outer rotor PMSM is taken as an example for illustration. Furthermore, the most critical uncertain factors are determined based on a well-calibrated finite element analysis (FEA) model. Finally, the employed FEA model is validated experimentally under different cooling conditions.