题目内容

矩阵式变频电路优点

A. 输出电压可控制为正弦波，频率不受电网频率的限制。
B. 输入电流也可控制为正弦波且和电压同相，功率因数为1，也可控制为需要的功率因数。
C. 能量可双向流动，适用于交流电动机的四象限运行。
D. 不通过中间直流环节而直接实现变频，效率较高。

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A. 涵洞
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