How does a VFD control the speed of an AC motor?
A. By varying the frequency of the voltage supplied to the motor
B. By varying the voltage supplied to the motor
C. By varying the current supplied to the motor
D. By varying the torque supplied to the motor
Answer:A
How does a VFD control the speed of an AC motor?
A. By varying the frequency of the voltage supplied to the motor B. By varying the voltage supplied to the motor C. By varying the current supplied to the motor D. By varying the torque supplied to the motor
Explanation: A VFD controls the speed of an AC motor by varying the frequency of the voltage supplied to the motor. This is known as frequency control or VFD. By varying the frequency of the voltage, the VFD can change the speed of the motor. The motor’s speed is directly proportional to the frequency of the voltage supplied to it. So, if the frequency is increased, the speed of the motor will also increase, and if the frequency is decreased, the speed of the motor will also decrease.