Parameter Determination of PMSM Using Coupled Electromagnetic and Thermal Model Incorporating Current Harmonics

• Published in: IEEE transactions on magnetics 2018-11, Vol.54 (11), p.1-5
• Main Authors: Mukundan, Shruthi, Dhulipati, Himavarsha, Tjong, Jimi, Kar, Narayan C.
• Format: Article
• Language: English
• Subjects: Circuits; Computational modeling; Decision analysis; Design optimization; Design parameters; Electromagnetic modeling; Equivalent circuits; Finite element method; finite-element analysis (FEA); Harmonic analysis; Harmonics; inductance; magnetic circuits; Magnetic saturation; Magnetism; Mathematical models; parameter determination; permanent magnet machines; Permanent magnets; Saturation magnetization; Stators; Synchronous machines; Temperature; Temperature effects; Thermal analysis; Windings
• ISSN: 0018-9464; 1941-0069
• DOI: 10.1109/TMAG.2018.2837087

With advent in permanent magnet synchronous machine (PMSM) structure and inverter topologies, accurate parameter determination is of significance for high-performance control, analysis, and making critical decisions on inter-dependent design parameter variations for machine optimization. However, the machine parameters, including permanent magnet (PM) flux linkage and dq -axis inductances, vary during operation with machine nonlinearities such as magnetic saturation, temperature rise, and the introduction of spatial- and time-harmonic contents contributing toward inaccuracies during machine parameter determination. While classical dq -axis modeling fails to accommodate non-sinusoidal winding distributions and the effects of temperature rise, finite-element analysis (FEA) is computationally expensive and coupling of electromagnetic and thermal analysis including current harmonics becomes complex. Therefore, in this paper, a novel magnetic equivalent circuit model incorporating the effects of temperature rise and current harmonics has been developed for parameter determination of PMSMs. A lumped thermal model is implemented to determine the temperatures at each point of the machine. The proposed coupled electromagnetic and thermal model has been validated for various operating conditions of a fractional-slot distributed wound laboratory PMSM with FEA and experimental investigations.