Electrical Engineering (EE) Exam > Electrical Engineering (EE) Questions > If the stator voltage and frequency of an ind...
Start Learning for Free
If the stator voltage and frequency of an induction motor are reduced proportionately,its
- a)locked rotor current is reduced
- b)torque developed is increased
- c)magnetising current is decreased
- d)both (a) & (b)
Correct answer is option 'D'. Can you explain this answer?
| FREE This question is part of | Download PDF Attempt this Test |
Most Upvoted Answer
If the stator voltage and frequency of an induction motor are reduced ...
**Explanation:**
When the stator voltage and frequency of an induction motor are reduced proportionately, the following changes occur:
**1. Locked Rotor Current is Reduced:**
- When the stator voltage and frequency are reduced proportionately, the reactance of the motor increases.
- As a result, the impedance of the motor increases and limits the flow of current through the motor.
- This reduction in current flow leads to a decrease in the locked rotor current of the motor.
- Therefore, option (a) is correct.
**2. Torque Developed is Increased:**
- The torque developed by an induction motor is directly proportional to the square of the stator voltage and inversely proportional to the stator frequency.
- When both the stator voltage and frequency are reduced proportionately, the torque developed by the motor increases.
- This is because the reduction in voltage is compensated by the reduction in frequency, resulting in a higher torque output.
- Therefore, option (b) is correct.
**3. Magnetising Current is Decreased:**
- The magnetising current of an induction motor is primarily dependent on the stator voltage.
- When the stator voltage is reduced proportionately, the magnetising current also decreases.
- This is because the reduced voltage results in a lower magnetic flux in the motor, leading to a decrease in the magnetising current.
- Therefore, option (c) is correct.
Hence, when the stator voltage and frequency of an induction motor are reduced proportionately, the locked rotor current is reduced, the torque developed is increased, and the magnetising current is decreased. Therefore, the correct answer is option (d) - both (a) and (b).
When the stator voltage and frequency of an induction motor are reduced proportionately, the following changes occur:
**1. Locked Rotor Current is Reduced:**
- When the stator voltage and frequency are reduced proportionately, the reactance of the motor increases.
- As a result, the impedance of the motor increases and limits the flow of current through the motor.
- This reduction in current flow leads to a decrease in the locked rotor current of the motor.
- Therefore, option (a) is correct.
**2. Torque Developed is Increased:**
- The torque developed by an induction motor is directly proportional to the square of the stator voltage and inversely proportional to the stator frequency.
- When both the stator voltage and frequency are reduced proportionately, the torque developed by the motor increases.
- This is because the reduction in voltage is compensated by the reduction in frequency, resulting in a higher torque output.
- Therefore, option (b) is correct.
**3. Magnetising Current is Decreased:**
- The magnetising current of an induction motor is primarily dependent on the stator voltage.
- When the stator voltage is reduced proportionately, the magnetising current also decreases.
- This is because the reduced voltage results in a lower magnetic flux in the motor, leading to a decrease in the magnetising current.
- Therefore, option (c) is correct.
Hence, when the stator voltage and frequency of an induction motor are reduced proportionately, the locked rotor current is reduced, the torque developed is increased, and the magnetising current is decreased. Therefore, the correct answer is option (d) - both (a) and (b).
Attention Electrical Engineering (EE) Students!
To make sure you are not studying endlessly, EduRev has designed Electrical Engineering (EE) study material, with Structured Courses, Videos, & Test Series. Plus get personalized analysis, doubt solving and improvement plans to achieve a great score in Electrical Engineering (EE).
|
Explore Courses for Electrical Engineering (EE) exam
|
|
Similar Electrical Engineering (EE) Doubts
Top Courses for Electrical Engineering (EE)View all
If the stator voltage and frequency of an induction motor are reduced proportionately,itsa)locked rotor current is reducedb)torque developed is increasedc)magnetising current is decreasedd)both (a) (b)Correct answer is option 'D'. Can you explain this answer?
Question Description
If the stator voltage and frequency of an induction motor are reduced proportionately,itsa)locked rotor current is reducedb)torque developed is increasedc)magnetising current is decreasedd)both (a) (b)Correct answer is option 'D'. Can you explain this answer? for Electrical Engineering (EE) 2024 is part of Electrical Engineering (EE) preparation. The Question and answers have been prepared according to the Electrical Engineering (EE) exam syllabus. Information about If the stator voltage and frequency of an induction motor are reduced proportionately,itsa)locked rotor current is reducedb)torque developed is increasedc)magnetising current is decreasedd)both (a) (b)Correct answer is option 'D'. Can you explain this answer? covers all topics & solutions for Electrical Engineering (EE) 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for If the stator voltage and frequency of an induction motor are reduced proportionately,itsa)locked rotor current is reducedb)torque developed is increasedc)magnetising current is decreasedd)both (a) (b)Correct answer is option 'D'. Can you explain this answer?.
If the stator voltage and frequency of an induction motor are reduced proportionately,itsa)locked rotor current is reducedb)torque developed is increasedc)magnetising current is decreasedd)both (a) (b)Correct answer is option 'D'. Can you explain this answer? for Electrical Engineering (EE) 2024 is part of Electrical Engineering (EE) preparation. The Question and answers have been prepared according to the Electrical Engineering (EE) exam syllabus. Information about If the stator voltage and frequency of an induction motor are reduced proportionately,itsa)locked rotor current is reducedb)torque developed is increasedc)magnetising current is decreasedd)both (a) (b)Correct answer is option 'D'. Can you explain this answer? covers all topics & solutions for Electrical Engineering (EE) 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for If the stator voltage and frequency of an induction motor are reduced proportionately,itsa)locked rotor current is reducedb)torque developed is increasedc)magnetising current is decreasedd)both (a) (b)Correct answer is option 'D'. Can you explain this answer?.
Solutions for If the stator voltage and frequency of an induction motor are reduced proportionately,itsa)locked rotor current is reducedb)torque developed is increasedc)magnetising current is decreasedd)both (a) (b)Correct answer is option 'D'. Can you explain this answer? in English & in Hindi are available as part of our courses for Electrical Engineering (EE).
Download more important topics, notes, lectures and mock test series for Electrical Engineering (EE) Exam by signing up for free.
Here you can find the meaning of If the stator voltage and frequency of an induction motor are reduced proportionately,itsa)locked rotor current is reducedb)torque developed is increasedc)magnetising current is decreasedd)both (a) (b)Correct answer is option 'D'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of
If the stator voltage and frequency of an induction motor are reduced proportionately,itsa)locked rotor current is reducedb)torque developed is increasedc)magnetising current is decreasedd)both (a) (b)Correct answer is option 'D'. Can you explain this answer?, a detailed solution for If the stator voltage and frequency of an induction motor are reduced proportionately,itsa)locked rotor current is reducedb)torque developed is increasedc)magnetising current is decreasedd)both (a) (b)Correct answer is option 'D'. Can you explain this answer? has been provided alongside types of If the stator voltage and frequency of an induction motor are reduced proportionately,itsa)locked rotor current is reducedb)torque developed is increasedc)magnetising current is decreasedd)both (a) (b)Correct answer is option 'D'. Can you explain this answer? theory, EduRev gives you an
ample number of questions to practice If the stator voltage and frequency of an induction motor are reduced proportionately,itsa)locked rotor current is reducedb)torque developed is increasedc)magnetising current is decreasedd)both (a) (b)Correct answer is option 'D'. Can you explain this answer? tests, examples and also practice Electrical Engineering (EE) tests.
|
|
Explore Courses for Electrical Engineering (EE) exam
|
|
Suggested Free Tests
Signup for Free!
Signup to see your scores go up within 7 days! Learn & Practice with 1000+ FREE Notes, Videos & Tests.
|
© EduRev
|
Education Revolution
|
Follow Us
|
Signup to see your scores
go up within 7 days!
Access 1000+ FREE Docs, Videos and Tests
Takes less than 10 seconds to signup