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Low frequency operation of a.c. series motor in traction application:
- a)Improves its commutation but starting current increases.
- b)Improves its commutation property but pf and n reduces.
- c)Improves its commutation, pf and efficiency.
- d)Adversely affects commutation but pf and n improve.
Correct answer is option 'C'. Can you explain this answer?
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Verified Answer
Low frequency operation of a.c. series motor in traction application:a...
Motor that can be used with a single-phase ac source as well as a dc source of supply voltages are called universal motor. However, a series motor which is specifically designed for dc operation suffers from the following drawbacks when it is used on single-phase ac supply:
Due to the high inductance of the field and the armature circuit, the power factor would become very low.
The main advantages of hybrid stepper motors compared with variable reluctance stepper motors are as follows:
1. Small step length.
2. Greater torque per unit volume.
3. Provides detent torque with windings de-energized.
4. Less tendency to resonate.
5. High efficiency at lower speed and lower stepping rates.
Disadvantages of hybrid stepper motors
1. High inertia and weight due to presence of rotor magnet.
2. Performance affected by change in magnetic strength.
3. More costly than variable reluctance stepper moto.
Due to the high inductance of the field and the armature circuit, the power factor would become very low.
The main advantages of hybrid stepper motors compared with variable reluctance stepper motors are as follows:
1. Small step length.
2. Greater torque per unit volume.
3. Provides detent torque with windings de-energized.
4. Less tendency to resonate.
5. High efficiency at lower speed and lower stepping rates.
Disadvantages of hybrid stepper motors
1. High inertia and weight due to presence of rotor magnet.
2. Performance affected by change in magnetic strength.
3. More costly than variable reluctance stepper moto.
Most Upvoted Answer
Low frequency operation of a.c. series motor in traction application:a...
Explanation:
In a traction application, the low frequency operation of an AC series motor has a positive impact on its performance. Let's understand the reasons behind this:
Improvement in Commutation:
- Commutation refers to the process by which the direction of current in the armature coil segments gets reversed at the appropriate time.
- In an AC series motor, commutation is crucial for the smooth operation of the motor.
- At low frequencies, the time available for the reversal of current direction increases, leading to improved commutation.
- This results in reduced sparking and better performance of the motor.
Improvement in Power Factor (PF):
- Power factor is a measure of how effectively the motor converts electrical power into mechanical power.
- At low frequencies, the power factor of an AC series motor improves because the reactive power component decreases.
- This leads to a more efficient utilization of electrical power and improved overall performance.
Improvement in Efficiency:
- Efficiency is the ratio of output power to input power.
- When an AC series motor operates at a low frequency, there is a decrease in the heat loss associated with the core and windings.
- This reduction in heat loss contributes to an increase in the overall efficiency of the motor.
Reduction in Speed (n):
- The operating speed of the motor decreases at low frequencies due to the reduced supply frequency.
- This reduction in speed can be advantageous in certain traction applications where low speed is desired, such as in locomotives or heavy machinery.
Therefore, the correct option is 'C' – the low frequency operation of an AC series motor in traction applications leads to improved commutation, power factor, and efficiency, while the speed decreases.
In a traction application, the low frequency operation of an AC series motor has a positive impact on its performance. Let's understand the reasons behind this:
Improvement in Commutation:
- Commutation refers to the process by which the direction of current in the armature coil segments gets reversed at the appropriate time.
- In an AC series motor, commutation is crucial for the smooth operation of the motor.
- At low frequencies, the time available for the reversal of current direction increases, leading to improved commutation.
- This results in reduced sparking and better performance of the motor.
Improvement in Power Factor (PF):
- Power factor is a measure of how effectively the motor converts electrical power into mechanical power.
- At low frequencies, the power factor of an AC series motor improves because the reactive power component decreases.
- This leads to a more efficient utilization of electrical power and improved overall performance.
Improvement in Efficiency:
- Efficiency is the ratio of output power to input power.
- When an AC series motor operates at a low frequency, there is a decrease in the heat loss associated with the core and windings.
- This reduction in heat loss contributes to an increase in the overall efficiency of the motor.
Reduction in Speed (n):
- The operating speed of the motor decreases at low frequencies due to the reduced supply frequency.
- This reduction in speed can be advantageous in certain traction applications where low speed is desired, such as in locomotives or heavy machinery.
Therefore, the correct option is 'C' – the low frequency operation of an AC series motor in traction applications leads to improved commutation, power factor, and efficiency, while the speed decreases.
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Low frequency operation of a.c. series motor in traction application:a)Improves its commutation but starting current increases.b)Improves its commutation property but pf and n reduces.c)Improves its commutation, pf and efficiency.d)Adversely affects commutation but pf and n improve.Correct answer is option 'C'. Can you explain this answer?
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Low frequency operation of a.c. series motor in traction application:a)Improves its commutation but starting current increases.b)Improves its commutation property but pf and n reduces.c)Improves its commutation, pf and efficiency.d)Adversely affects commutation but pf and n improve.Correct answer is option 'C'. Can you explain this answer? for SSC 2024 is part of SSC preparation. The Question and answers have been prepared according to the SSC exam syllabus. Information about Low frequency operation of a.c. series motor in traction application:a)Improves its commutation but starting current increases.b)Improves its commutation property but pf and n reduces.c)Improves its commutation, pf and efficiency.d)Adversely affects commutation but pf and n improve.Correct answer is option 'C'. Can you explain this answer? covers all topics & solutions for SSC 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Low frequency operation of a.c. series motor in traction application:a)Improves its commutation but starting current increases.b)Improves its commutation property but pf and n reduces.c)Improves its commutation, pf and efficiency.d)Adversely affects commutation but pf and n improve.Correct answer is option 'C'. Can you explain this answer?.
Low frequency operation of a.c. series motor in traction application:a)Improves its commutation but starting current increases.b)Improves its commutation property but pf and n reduces.c)Improves its commutation, pf and efficiency.d)Adversely affects commutation but pf and n improve.Correct answer is option 'C'. Can you explain this answer? for SSC 2024 is part of SSC preparation. The Question and answers have been prepared according to the SSC exam syllabus. Information about Low frequency operation of a.c. series motor in traction application:a)Improves its commutation but starting current increases.b)Improves its commutation property but pf and n reduces.c)Improves its commutation, pf and efficiency.d)Adversely affects commutation but pf and n improve.Correct answer is option 'C'. Can you explain this answer? covers all topics & solutions for SSC 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Low frequency operation of a.c. series motor in traction application:a)Improves its commutation but starting current increases.b)Improves its commutation property but pf and n reduces.c)Improves its commutation, pf and efficiency.d)Adversely affects commutation but pf and n improve.Correct answer is option 'C'. Can you explain this answer?.
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Low frequency operation of a.c. series motor in traction application:a)Improves its commutation but starting current increases.b)Improves its commutation property but pf and n reduces.c)Improves its commutation, pf and efficiency.d)Adversely affects commutation but pf and n improve.Correct answer is option 'C'. Can you explain this answer?, a detailed solution for Low frequency operation of a.c. series motor in traction application:a)Improves its commutation but starting current increases.b)Improves its commutation property but pf and n reduces.c)Improves its commutation, pf and efficiency.d)Adversely affects commutation but pf and n improve.Correct answer is option 'C'. Can you explain this answer? has been provided alongside types of Low frequency operation of a.c. series motor in traction application:a)Improves its commutation but starting current increases.b)Improves its commutation property but pf and n reduces.c)Improves its commutation, pf and efficiency.d)Adversely affects commutation but pf and n improve.Correct answer is option 'C'. Can you explain this answer? theory, EduRev gives you an
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