单选题Which of the following statements is true concerning all three-phase alternators?（）AEach has three separate but identical armature windings acted on by one system of rotating magnetsBEach has one armature winding acted on by three identical but separate systems of rotating magnetsCAll three-phase alternators are designed to operate with a O8 leading power factorDThe three phases always provide power to the load through three sets of slip rings and brushes
单选题
Which of the following statements is true concerning all three-phase alternators?（）
A
Each has three separate but identical armature windings acted on by one system of rotating magnets
B
Each has one armature winding acted on by three identical but separate systems of rotating magnets
C
All three-phase alternators are designed to operate with a O8 leading power factor
D
The three phases always provide power to the load through three sets of slip rings and brushes
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