三相全控桥式整流电路带大电感负载时,在负载二端续流二极管。
A. 必须要接
B. 不可接 D.必须串联连接
C. 可接可不接
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三相半控桥式整流电路带电阻负载时,其输出直流电压的波形在的范围内是连续的。
A. a<60°
B. a<30°
C. 30° D. a>30°
Carly was named“The Most Powerful Woman in Business“byBusiness Week in1999.
A. 对
B. 错
Carly started her business career from Assistant’s desk to CEO due to her own efforts.
A. 对
B. 错
HP’s big success has much to do with Carly’s leadership and devotion.
A. 对
B. 错
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