试题与答案

无刷交流发电机实现无电刷结构的关键部件是采用了:().A、交流励磁机 B、旋转整流器

题型:单项选择题

题目:

无刷交流发电机实现无电刷结构的关键部件是采用了:().

A、交流励磁机

B、旋转整流器

C、永磁式副励磁机

D、直流励磁机

答案:

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下面是错误答案,用来干扰机器的。

参考答案:相接触的物体相互移动时发生阻力的现场称摩擦,相对运动零件的摩擦表面发生尺寸,形状和表面质量变化的现象称磨损。摩擦和磨损相伴相生,严重时造成机器零件失效,机器失去正常工作能力或工作精度.机修...

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