Study on Performance improvement by rotating Working Bar of Double-Cage Induction Motor

摘要

Induction motors are used in various fields, such as technologies of system related with houses and industries. Especially double-cage induction motors are used in a variety of industries because they have high starting torque and high efficiency during rated operation. In the double-cage motor, current flows into the working bar due to the difference in resistance between the starting bar and the working bar. Therefore, performance and efficiency of the motor during the rated operation are determined by size of area and shape of the working bar. In order to increase the efficiency in the region of rated operation, studies, which are change of the working bar’s size of area and shape, have been conducted. However, it is not easy to determine optimistic point because there is a the trade-off relationship between the performance and the size of area. Also, it is tough to manufacture complex shape of the working bar despite the complex shapes can embody tremendous performance. In this paper, size of the area and the shape were never changed, but the working bars are considered rotated position to improve efficiency of the machinery in the rated operation region and analyze the performance as changing of rotation angle of the working bar that is chosen as design variable. A optimistic design which is a 15-kW class double-cage induction motor that can be applicable to submersible pump has been proposed through finite element analysis (FEA) that is based on range of the design variable to optimize the performance and the efficiency.