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 国家开放大学 / 安装工程估价

三相交流电与单相交流电相比具有（ ）优点。


a.
三相四线制是把发电机的三个线圈的末端连接在一起，成为一个公共端点（称中性点）

b.
现在生产上广泛使用的三相异步电动机是以三相交流作为电源的，它与单相电动机相比，具有体积小、价格低、效率高、性能好等优点

c.
在输送的功率、电压相同和距离、线路损失相等的情况下，采用三相制输电可大大节省输电线的用铜（或铝）量

d.
体积相同时，三相交流发电机具有输出功率大、效率高等优点
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