单选题In a modern three-phase A-Csynchronous brushless generator, the excitation winding is on the rotorThat means （）.AThe generator needs not excitationBThe winding on the rotor is for inputting excitation currentCThere are three phase windings on the rotorDThe generator has brushes
单选题
In a modern three-phase A-Csynchronous brushless generator, the excitation winding is on the rotorThat means （）.
A
The generator needs not excitation
B
The winding on the rotor is for inputting excitation current
C
There are three phase windings on the rotor
D
The generator has brushes
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