If an AC servomotor has one of its winding excited by AC, then voltage measured at the other winding with rotor running will be
A. zero.
B. proportional to rotor speed.
C. proportional to square of rotor speed.
D. constant independent of speed.
Answer: B
Share your understanding of this question with the correct explanation.
If an AC servomotor has one of its windings excited by AC, the voltage measured at the other winding with the rotor running will be proportional to the rotor speed.
In an AC servomotor, one winding is used as the input or control winding, and the other winding is used as the output or feedback winding. The input winding is typically excited by an AC signal to generate a rotating magnetic field, while the output winding produces a voltage proportional to the speed of the rotor.
As the rotor of the motor rotates, it cuts through the magnetic field created by the input winding. This motion induces a voltage in the output winding, which is proportional to the rate of change of magnetic flux and therefore proportional to the rotor speed. This voltage can be measured and used as feedback to control the motor’s speed or position.
Therefore, option B, “proportional to rotor speed,” is the correct answer.