Consider the following statements about torque in synchronous motors. I. The torque in a synchronous motor is produced only when the rotor is locked into synchronism. II. The torque is directly proportional to the sine of the load angle (δ). III. Synchronous motor develops starting torque proportional to the power input. IV. Maximum torque occurs at δ = 180°. Which of the above statements are correct?
Statements I & II only
To determine the correct statements about torque in synchronous motors, let's evaluate each statement step by step:
- Statement I: The torque in a synchronous motor is produced only when the rotor is locked into synchronism.
- Statement II: The torque is directly proportional to the sine of the load angle (δ).
- Statement III: Synchronous motor develops starting torque proportional to the power input.
- Statement IV: Maximum torque occurs at δ = 180°.
Based on the above evaluations, the correct statements are Statement I and Statement II only.
Similar Questions
Which of the following is a key maintenance practice for reliable operation of a 3-phase induction motor?
If the frequency of an AC source is doubled, the impedance of a pure resistor ____________.
Which of the following sets of statements about the causes of errors in current transformers is correct?
i) Leakage reactance in secondary winding contributes to ratio error
ii) High magnetizing current increases phase angle error
iii) Burden with low power factor increases phase angle error
iv) Core saturation reduces both ratio and phase angle errors
A single-phase preventer continuously monitors and protects preferably which motor against phase failure?
Important Questions from Three Phase Induction Motor
The stator of a 3-phase induction motor has 4 slots per pole phase. If the supply frequency is 50 Hz, calculate the number of stator poles produced and the total number of slots on the stator, respectively.
In an induction motor for a value slip(s) = 0, the torque (T) is
The stator of a 3-phase induction motor has 2 slots per pole per phase. If supply frequency is 50 Hz, then calculate the number of stator poles and total number of slots on the stator.
If all the stator coils of a motor are connected for the same magnetic polarity, there will be formed an equal number of ________.
The shaft of an induction motor is made of
