Development of dual air gap printed coil BLDC motor

Small effective air gap is one of the major design considerations to improve performance in brushless DC motors. In axial gap motors, however, it is limited by thickness of armature coil as well as the friction loss in a bearing due to the axial magnetic force. This paper investigated the magnetic field, force, torque and loss in an axial gap motor using finite element method (FEM) and Maxwell stress tensor, and developed a novel shape of dual air gap printed coil motor which increases the performance as well as the manufacturing flexibility.