In order to save resources and prevent global warming, it has been urgently needed to reduce CO2 emissions and decrease automobile fuel consumption in recent years. The trend in automotive applications are being studied to improve fuel efficiency and to reduce volume and weight. For these reasons, the mechanical parts of the automobile are being replaced by electric components.
This paper deals with the optimum design process for a small Brushless DC (BLDC) motor used in Electric-Continuous Variable Valve Timing (E-CVVT) system in automobiles with internal combustion engines. It is also proposed to improve the rated efficiency and the maximum torque and reduce the cogging torque to improve the characteristics of the BLDC motor. To maximize the maximum torque as well as to maintain the rated efficiency, the radial basis function based on latin hypercube sampling and genetic algorithm are utilized. The design variables, objective functions, and constraints are selected for the optimum design of the BLDC motor, which is divided into three steps. Step I and step II are calculated to improve the rated efficiency and the maximum torque respectively, while step III utilizes to reduce cogging torque. To verify the proposed optimum design process, the improvement of characteristic is suggested with FE-analysis.