Design and analysis of high power density direct drive interior permanent magnet synchronous motor for electric vehicles

Advances in electric vehicle technology are critical to reducing the negative impact of fossil fuels on transportation and industry. In this context, a permanent magnet synchronous motor (PMSM) with a power of 1.4 kW and a speed of 1100 rpm has been designed and analyzed. PMSMs offer a suitable performance for electric vehicle applications with high power factor, power density and torque capabilities. Using an internal rotor structure and permanent magnets in the rotor increases the mechanical strength of the motor, providing stability and performance at high speeds. The effect of different slot-pole configurations and aspect ratios on motor performance is investigated. In addition, the effect of slot-pole configurations on the knocking torque is analyzed. Since there are many dependent and independent variables in motor sizing, in the first step, the effect of the number of conductors per slot, stator tooth thickness and stator yoke on the efficiency is investigated by parametric optimization. The parameter values determined in the first step were kept constant in the second step. Optimization was performed using the multi-objective genetic algorithm (MOGA) method for the other variables and the efficiency was obtained at 94% and above. As a result of the optimization studies, different motor designs were compared, and the 39-slot, 10-pole motor model was determined to be the most suitable design. In this design process, critical factors such as efficiency, power density, torque capabilities, dimensions and cooling requirements, and motor dimensions that best meet the requirements of electric vehicles were determined. The initial design and the finite element analysis optimization models of the 39-slot, 10-pole motor were investigated using finite element analysis. This analysis was performed by two-dimensional modeling method and the results are presented comparatively. Improvements from the initial design through the MOGA optimization process are observed. The engine configuration determined after the SEA showed a performance close to the desired values.