| Abstract: | Aimed at providing small high‐power motors with excellent efficiency, a motor stator with rectangular‐wire lap windings and an automatic process for its production were developed. The structure of the windings, namely, two continuous “α‐shaped” coils, and the coil‐production method (involving simultaneous coil forming and coil insertion) enable mass production of this stator. The slot‐fill rate for a prototype stator was 80.5%, and the total height of the coil ends was 60 mm to 72 mm. On the basis of the ratio of the sectional areas of two types of the motors, its efficiency was estimated to be 3.7% higher than the efficiencies of motor stators with round‐wire concentric windings (at a rotation speed of 1000/min). In addition, the number of coil parts and the number of welding points were greatly reduced compared to those of a stator with segmented‐coil wave windings. |
