某小型水电站的电能输送示意图如下，发电机的输出电压为200 V，输电线总电阻为r

发布时间：2017-07-02 18:20 │ 来源：www.tikuol.com

题型：不定项选择

问题：

某小型水电站的电能输送示意图如下，发电机的输出电压为200 V，输电线总电阻为r，升压变压器原副线圈匝数分别为n₁、n₂，降压变压器原副线圈匝数分别为n₃、n₄（变压器均为理想变压器）。要使额定电压为220 V的用电器正常工作，则

[ ]

A．

B．

C．升压变压器的输出电压等于降压变压器的输入电压

D．升压变压器的输出功率大于降压变压器的输入功率

考点：远距离输电的相关计算

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