说明：  《电机及拖动基础》顾绳谷 第四版 机械工业出版社 课后答案 习题解答 学习指导，电机基础课程的参考答案，值得借鉴
( Motor and drag the foundation Gu rope Valley Fourth Edition Machinery Industry Publishing House after school answer exercises to learn the guidance of the basic course of the motor reference answer, it is worth learning)