Conventional motor constants used for evaluating motor performance and efficiency often overlook the impact of iron loss and current angle. This thesis introduces a novel motor constant definition that incorporates both iron loss, copper loss, and current angle, providing a comprehensive indicator for assessing motor efficiency and performance. To enhance the efficiency and performance of permanent magnet synchronous machines, a holistic consideration of various motor design factors is necessary. However, the utilization of multi-objective optimization methods to maximize motor efficiency presents challenges due to their complex algorithms and extensive computational requirements when combined with finite element analysis. By leveraging the proposed motor constant, including the current angle, the multi-objective optimization problem can be simplified into a single objective optimization, streamlining the optimization process.
In this research, a Genetic Algorithm (GA) optimization method utilizing the new motor constant, considering the current angle, as the fitness function is employed to identify optimal parameters for the motor stator, thereby maximizing the high-efficiency operating range and high-speed region. The research findings demonstrate the accurate correlation between the new motor constant and motor efficiency, including the effect of the current angle. Furthermore, the Genetic Algorithm optimization method, based on this motor constant, yields optimal motor designs with broader high-efficiency operating ranges. The electromagnetic characteristics of the designed motors are thoroughly investigated and validated through finite element analysis using JMAG software.
Finally, a 300W spoke type and An IPM 10kW motor, specifically tailored to meet the requirements of EV applications, is fabricated, and tested to assess its performance and validate the accuracy of simulation analysis.
This study presents a novel motor constant definition that incorporates iron loss, current angle, and copper loss, enabling a comprehensive assessment of motor performance and efficiency. The application of the proposed motor constant, considering the current angle, in the optimization process simplifies the multi-objective optimization problem and leads to enhanced motor designs with broader high-efficiency operating ranges. The research outcomes contribute to the advancement of motor design and optimization techniques, providing valuable insights for the development of high-performance electric motors for various applications.

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