Quantification and Propagation of Uncertainty in the Magnetic Characteristic of Steel and Permanent Magnets of a Synchronous Machine Drive

The numerical calculation of the electromagnetic fields within a permanent magnet synchronous machine (PMSM) is sensitive to the magnetic characteristic of steel and permanent magnets. The objective of this work is to quantify the impact of magnetization curve uncertainties on the performance of a PMSM and its drive system. Our approach is as follows. First, we construct stochastic models that reflect the uncertainties in B–H curves and PM remanent flux density. Second, to overcome the computational limitations of finite element analysis, we replace it with surrogate models based on Gaussian process regression. Third, we perform uncertainty propagation studies to assess the combined effect of steel and PM uncertainties on the maximum average torque vs. speed characteristics and the minimum dc-link voltage.