Efficient Iron Loss Estimation of Interior PMSMs in Electric Vehicles: Analytical Modelling and Experimental Validation

The loss performance of interior permanent magnet synchronous motors (IPMSMs), commonly employed in electric drive systems of electric vehicles (EVs), is notably influenced by temperature fluctuations and harmonics in the supply current, because the magnetic properties of silicon steel sheets are easily vulnerable to these factors. Therefore, in this paper, an advanced experimental setup is utilized to quantify the AC loss of silicon steel samples under rotating magnetic fields. Then, an enhanced analytical estimation model of the iron loss in IPMSMs is formulated by incorporating experimentally-fitted coefficients for hysteresis and eddy current losses, allowing for a comprehensive consideration of temperature variations and harmonics. Given that several calculation methods demonstrated satisfactory accuracy, when relying solely on the no-load iron loss, the efficacy of the proposed model is validated through loaded experiments. Moreover, comparative results verify the improved accuracy and computational simplicity of the presented model, even under the dynamic drive cycle conditions of EVs. The proposed tester and approaches can also be applied to the design optimization of electric motors with high-temperature superconducting (HTS) materials.