Design and optimization of permanent magnet dc motor for electric bicycles

Electric bicycle technology is rapidly developing and becoming widespread. In this way, cycling gains a more effective position in transportation. The most important part in determining the performance of the electric bicycle system is the electric motor. Motor specifications must be within legal limits. An efficient system should be established in terms of electrical and user comfort. In this study, brushless direct current motor design is used for electric bicycles. Preliminary design characteristics were determined taking into account the legal limitations that define electric bicycles. After the dimensions were found to be suitable for the desired power and moment, the winding structure was decided. In the selection of the number of slot/pole, 7 models selected in the winding factor were compared with 2-dimensional analysis by finite element method and 36/38 slot/pole number were selected. After selecting the materials to be used in the design, the optimization process of the selected 36/38 slot/pole model was started. In ANSYS RMxprt program, the dimensions and properties of which are affected by the motor performance have been parameterized and analyzed. Accordingly, the best design that meets the desired characteristics has been determined. The selected design was examined by finite element method in ANSYS Maxwell program in 2 and 3 dimensions. As a result of this study, it has been stated that the optimized design meets the machine design criteria and is usable in electric bicycles.