KONGUNADU COLLEGE OF ENGINEERING AND TECHNOLOGY
(AUTOMONOUS)
NAMAKKAL - TRICHY MAIN ROAD, THOTTIAM, TRICHY
DEPARTMENT OF MECHANICAL ENGINEERING
YEAR - II
SEM - III
DEPT : MECH
ACADEMIC YEAR: 2022-2023
20EE306-ELECTRICAL DRIVES AND CONTROLS
GIVEN DATE: 13.09.2022
S.No
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2.
3.
Register No
621321114001
621321114002
621321114003
Student Name
AAKASH K
ABINOW PANDIAN K
AJITH B
TARGET DATE: 17.09.2022
ASSIGNMENT – I
Assignment Topics
Discuss about the choice of selection of the motor for different loads
The enclosure of a 25 kW motor is equivalent to a cylinder of a 80 cm diameter
and 95 cm length. The motor weighs 575 kg. Assuming the specific heat is
780J/kg / °C and that the peripheral surface of the enclosure of the motor alone is
capable of heat dissipation of 14.5 W/sq-m/ °C, calculate the heating time
constant of the motor and its final temperature rise. Efficiency of the motor is 75
%.
Analyze the DC shunt and series motors with voltage equations.
Derive the torque equation and power equation of DC motor.
Analyze selection of power rating for drive motors with regard to thermal over
loading.
Compare Electric drive and mechanical drive.
Analyze the DC shunt motor characteristics with different V, Rsh, Ra
A 4 pole d.c motor has lap connected armature winding. The flux per pole is
30mWb. The number of armature conductors is 250. When connected to 230V.
Supply it draws an armature current of 40A. Calculate the back emf and the
speed of with which motor is running. Assume armature resistance is 0.6 Ω.
Analyze the factors governing the selection of electric drives for any
particular applications
The temperature rise of motor after operating for 30 minutes on full load
is 200°C and after another 30 minutes it becomes 30°C on the same load.
Find the final temperature rise and time constant
Apply the induction principle and explain the working of 3 phase induction
Blooms
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621321114004
621321114005
621321114006
AJITH J
ANANDHARAJ S
ANTONY JERISH M
motor with effect of slip.
A 4 pole dc motor takes a 50 A armature current. The armature has lap
connected 480 conductors. The flux per pole is 20 mWb. Calculate the gross
torque developed by the armature of the motor.
A 220V, d.c motor has an armature resistance of 0.75Ω. It is during an armature
current of 30A, driving a certain load. Calculate the induced emf in the motor
under this condition.
The temperature rise of motor after operating for 30 minutes on full load is200C
and after another 30 minutes it becomes 30°C on the same load. Find the final
temperature rise and time constant.
The heating and cooling time constants of an electric motor are 100 and 150
minutes respectively. The rating of the motor is 125 kW. If it is working on duty
cycle of 15 minutes on load and 30 minutes on no load, determine the
permissible overloading of the motor. Assume the losses are given by the
expression .
Analyze the DC series motor characteristics with different V, Rsh, Ra
A 4 pole, 3 phase, 50 Hz star connected induction motor has a full load slip of
4%. Calculate full load speed of the motor.
A three phase induction motor is wound for 4 poles and is supplied from 50Hz
system. Calculate a) the synchronous speed. b) The speed of the motor when
slip is 4.1.
Compare group drive ,individual drive and multimotor drive list their advantages
and disadvantages.
At full load of 5 H.P., temperature rise of a motor is 15°C after one hour and
30°C after two hours. Find i) The final temperature rise on full load ii) Heating
time constant of motor.
Discuss the constructional difference of 3 phase squirrel cage and slip ring
induction motor
A 35kW, 440V dc shunt motor is braked by the plugging. Armature resistance is
0.1 ohm. Full load armature current is 100A and full load speed is 600rpm.
Calculate the value of the resistance to be placed in series with the armature
circuit to limit the corresponding braking torque.
Drive the expression for the final temperature rise in a motor
In a certain electric drive, the temperature rise is 25°C afterone hour
and37.5°C after two hours, starting from cold conditions. The ambient
temperature is 30°C.
1. Find steady temperature and the heating time constant.
2. When disconnected, the temperature falls from the final steady value
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to 40°C in 1.5 hours, calculate the cooling time constant.
7.
8.
9.
621321114007
621321114008
621321114009
ANTONY RABIN S
ARUN S B
ARUNKUMAR A
Evaluate the effect of slip in rotor emf, reactance , and impedance.
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2
Calculate the emf of a 6 pole DC motor having 480 conductors and driven
at a speed of 1200 rpm. The flux per pole is 0.012 Wb. Assume the
generator to the (a) lap wound, (b) wave wound.
A wave connected armature winding has 19 slots with 54 conductors per
slot. If the flux per pole is 0.025 Wb and number of pole is 8, find the
speed at which the motor should be run to give 513 V. Also find the
speed if the armature is lap connected.
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Analyze the basic drive system with its diagram.
The temperature rise of motor after operating for 20 minutes on full load is 10°C
and after another 20 minutes it becomes 20°C on the same load. Find the final
temperature rise and time constant.
A 6 pole d.c motor has lap connected armature winding. The flux per pole is
30mWb. The number of armature conductors is 200. When connected to 230V.
Supply it draws an armature current of 40A. Calculate the back emf and the
speed of with which motor is running. Assume armature resistance is 0.6 Ω.
Analyze the DC compound motor characteristics with different V, Rsh, Ra
Classify the drives based on source and industrial applications
A motor has a thermal heating time constant of 45 minutes. When the motor runs
continuously on full load, its final temperature rises to 80 degree Celsius.
i)What would be the temperature rise after 1 hour, if the motor runs continuously
on full load?
ii)If the temperature rises on 1 hour rating is allowed to be 75 degree Celsius,
find what would be the new steady state temperature at this rating.
Derive the Torque equation of DC motor.
Apply the induction principle and explain the working of 3 phase induction
motor with effect of slip.
The 10 minutes rating of a motor used in domestic mixer is 200 watts. The
heating time constant is 40 minutes and the maximum efficiency occurs at full
load (continuous). Determine the continuous rating.
A motor is required to deliver a load which follows the following cycle: 50 kW
for 10 minutes; no load for 4 minutes; 25 kW for 10 minutes; no load for 6
minutes. The cycle is repeated indefinitely. Find the suitable capacity of a
continuously rated motor for the purpose.
In a certain electric drive, the temperature rise is 30°C afterone hour and
35.5°C after two hours, starting from cold conditions. The ambient
temperature is 30°C.
1. Find steady temperature and the heating time constant.
2. When disconnected, the temperature falls from the final steady value
to 40°C in 1.5 hours, calculate the cooling time constant.
10.
11.
12.
621321114010
621321114011
621321114012
ASHOK M
ASHOK P
BALA GURU M
A 6 pole dc motor takes a 40 A armature current. The armature has lap
connected 480 conductors. The flux per pole is 20 mWb. Calculate the gross
torque developed by the armature of the motor.
A 220V, d.c motor has an armature resistance of 0.60Ω. It is during an armature
current of 20A, driving a certain load. Calculate the induced emf in the motor
under this condition.
Apply various slips to torque equation and explain the characteristics of
induction motor
Discuss about the elements of drive system with its diagram.
A motor has a thermal heating time constant of 35 minutes. When the motor runs
continuously on full load, its final temperature rises to 85 degree Celsius.
i)What would be the temperature rise after 1 hour, if the motor runs continuously
on full load?
ii)If the temperature rises on 1 hour rating is allowed to be 75 degree Celsius,
find what would be the new steady state temperature at this rating.
Apply the induction principle and explain the working of 3 phase induction
motor with effect of slip.
A 2 pole d.c motor has lap connected armature winding. The flux per pole is
20mWb. The number of armature conductors is 100. When connected to 230V.
Supply it draws an armature current of 20A. Calculate the back emf and the
speed of with which motor is running. Assume armature resistance is 0.6 Ω.
Compare the drives based on source and industrial applications
At full load of 10 H.P., temperature rise of a motor is 30°C after one hour and
40°C after two hours. Find i) The final temperature rise on full load ii) Heating
time constant of motor.
Analyze the DC series motors and compound with voltage equations.
A 4 pole d.c motor has lap connected armature winding. The flux per pole is
10mWb. The number of armature conductors is 100. When connected to 230V.
Supply it draws an armature current of 20A. Calculate the back emf and the
speed of with which motor is running. Assume armature resistance is 0.6 Ω.
The 15 minutes rating of a motor used in domestic mixer is 200 watts. The
heating time constant is 40 minutes and the maximum efficiency occurs at full
load (continuous). Determine the continuous rating.
A motor is required to deliver a load which follows the following cycle: 40 kW
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for 10 minutes; no load for 4 minutes; 25 kW for 10 minutes; no load for 6
minutes. The cycle is repeated indefinitely. Find the suitable capacity of a
continuously rated motor for the purpose.
The temperature rise of motor after operating for 30 minutes on full load is 20°C
and after another 40 minutes it becomes 40°C on the same load. Find the final
temperature rise and time constant.
A 45kW, 400V dc shunt motor is braked by the plugging. Armature resistance is
0.1 ohm. Full load armature current is 100A and full load speed is 600rpm.
Calculate the value of the resistance to be placed in series with the armature
circuit to limit the corresponding braking torque.
Analyze the different regions of T-S characteristics of induction motor.
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Apply the conditions and derive the Tst and Tmax of induction motor.
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Calculate the emf of a 4 pole DC motor having 400 conductors and driven
at a speed of 1200 rpm. The flux per pole is 0.012 Wb. Assume the
generator to the (a) lap wound, (b) wave wound.
A wave connected armature winding has 20 slots with 56 conductors per
slot. If the flux per pole is 0.025 Wb and number of pole is 8, find the
speed at which the motor should be run to give 500 V. Also find the
speed if the armature is lap connected.
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Drive the expression for the final temperature rise in a motor.
In a certain electric drive, the temperature rise is 35°C afterone hour
and36.5°C after two hours, starting from cold conditions. The ambient
temperature is 20°C.
1. Find steady temperature and the heating time constant.
2. When disconnected, the temperature falls from the final steady value
to 40°C in 1.5 hours, calculate the cooling time constant.
13.
14.
15.
621321114013
621321114014
621321114015
BALAMURUGAN K
BALASINGAM M
BAVANANDHAN S
Discuss about the elements of closed loop drive system with its diagram.
A motor has a thermal heating time constant of 40 minutes. When the motor runs
continuously on full load, its final temperature rises to 80 degree Celsius.
i)What would be the temperature rise after 1 hour, if the motor runs continuously
on full load?
ii)If the temperature rises on 1 hour rating is allowed to be 70 degree Celsius,
find what would be the new steady state temperature at this rating.
Analyze the T-N, T-Ia, N-Ia characteristics of DC shunt motors.
Apply the induction principle and explain the working of 3 phase induction
motor with effect of slip.
Differentiate the various electrical drives.
At full load of 5 H.P., temperature rise of a motor is 30°C after one hour and
40°C after two hours. Find i) The final temperature rise on full load ii) Heating
time constant of motor.
Draw and explain the characteristics of 3 phase induction motor.
Apply double field revolving theory and explain the working of single
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In a certain electric drive, the temperature rise is 25°C afterone hour and
35°C after two hours, starting from cold conditions. The ambient
temperature is 20°C.
1. Find steady temperature and the heating time constant.
2. When disconnected, the temperature falls from the final steady value
to 40°C in 1.5 hours, calculate the cooling time constant.
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Derive the torque equation and relate torque and speed equation of DC motor.
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2
Calculate the emf of a 4 pole DC motor having 480 conductors and driven
at a speed of 1000 rpm. The flux per pole is 0.012 Wb. Assume the
generator to the (a) lap wound, (b) wave wound.
A wave connected armature winding has 18 slots with 54 conductors per
slot. If the flux per pole is 0.025 Wb and number of pole is 8, find the
speed at which the motor should be run to give 513 V. Also find the
speed if the armature is lap connected.
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Analyze the various drives based on source and industrial applications
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phase induction motor.
Drive the expression for the final temperature reduction in a motor.
16.
17.
18.
621321114016
621321114017
621321114018
BHARATH KUMAR M
BHARATHI P
BOOMINATHAN J
The 10 minutes rating of a motor used in domestic mixer is 100 watts. The
heating time constant is 40 minutes and the maximum efficiency occurs at full
load (continuous). Determine the continuous rating.
A motor is required to deliver a load which follows the following cycle: 50 kW
for 20 minutes; no load for 4 minutes; 35 kW for 10 minutes; no load for 6
minutes. The cycle is repeated indefinitely. Find the suitable capacity of a
continuously rated motor for the purpose.
Discuss the stator and rotor constructional difference of single phase induction
motor.
A 55kW, 440V dc shunt motor is braked by the plugging. Armature resistance is
0.2 ohm. Full load armature current is 150A and full load speed is 600rpm.
Calculate the value of the resistance to be placed in series with the armature
circuit to limit the corresponding braking torque.
Analyze the motor at running condition and drive the heating time constant and
final steady state temperature
The temperature rise of motor after operating for 30 minutes on full load is 25°C
and after another 40 minutes it becomes 350°C on the same load. Find the final
temperature rise and time constant.
Apply double field revolving theory and explain the working of single
phase induction motor.
19.
20.
621321114019
621321114020
CHANDRU G
CHANDRU S
A 6 pole dc motor takes a 30 A armature current. The armature has lap
connected 480 conductors. The flux per pole is 10 mWb. Calculate the gross
torque developed by the armature of the motor.
A 220V, d.c motor has an armature resistance of 0.80Ω. It is during an armature
current of 20A, driving a certain load. Calculate the induced emf in the motor
under this condition.
Discuss about the elements of closed loop drive system with its diagram.
A motor has a thermal heating time constant of 45 minutes. When the motor runs
continuously on full load, its final temperature rises to 90 degree Celsius.
i)What would be the temperature rise after 1 hour, if the motor runs continuously
on full load?
ii)If the temperature rises on 1 hour rating is allowed to be 75 degree Celsius,
find what would be the new steady state temperature at this rating.
Analyze the different types of single phase induction motor.
Apply the induction principle and explain the working of 3 phase induction
motor with effect of slip.
The 15 minutes rating of a motor used in domestic mixer is 250 watts. The
heating time constant is 40 minutes and the maximum efficiency occurs at full
load (continuous). Determine the continuous rating.
A motor is required to deliver a load which follows the following cycle: 60 kW
for 10 minutes; no load for 4 minutes; 20 kW for 10 minutes; no load for 6
minutes. The cycle is repeated indefinitely. Find the suitable capacity of a
continuously rated motor for the purpose.
At full load of 10 H.P., temperature rise of a motor is 20°C after one hour and
40°C after two hours. Find i) The final temperature rise on full load ii) Heating
time constant of motor.
Analyze the T-N, T-Ia, N-Ia characteristics of DC compound motors.
Calculate the emf of a 8 pole DC motor having 500 conductors and driven
at a speed of 1400 rpm. The flux per pole is 0.012 Wb. Assume the
generator to the (a) lap wound, (b) wave wound.
A wave connected armature winding has 18 slots with 54 conductors per
slot. If the flux per pole is 0.045 Wb and number of pole is 8, find the
speed at which the motor should be run to give 500 V. Also find the
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speed if the armature is lap connected.
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621321114021
621321114022
DEEPAK M
DHANABALAN S
Analyze the motor at running condition and drive the heating time constant and
final steady state temperature
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In a certain electric drive, the temperature rise is 25°C after one hour
and34.5°C after two hours, starting from cold conditions. The ambient
temperature is 35°C.
1. Find steady temperature and the heating time constant.
2. When disconnected, the temperature falls from the final steady value
to 40°C in 1.5 hours, calculate the cooling time constant.
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Apply the conditions and derive the starting and maximum torque of induction
motor.
A 4 pole d.c motor has lap connected armature winding. The flux per pole is
30mWb. The number of armature conductors is 200. When connected to 230V.
Supply it draws an armature current of 10A. Calculate the back emf and the
speed of with which motor is running. Assume armature resistance is 0.5 Ω.
Analyze the motor at rest condition and drive the heating time constant and final
steady state temperature
A motor has a thermal heating time constant of 40 minutes. When the motor runs
continuously on full load, its final temperature rises to 90 degree Celsius.
i)What would be the temperature rise after 1 hour, if the motor runs continuously
on full load?
ii)If the temperature rises on 1 hour rating is allowed to be 75 degree Celsius,
find what would be the new steady state temperature at this rating.
Compare the constructional difference of 3 phase squirrel cage and slip ring
induction motor
Apply double field revolving theory and explain the working of single
phase induction motor.
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621321114023
DHANUSH R
The 15 minutes rating of a motor used in domestic mixer is 200 watts. The
heating time constant is 40 minutes and the maximum efficiency occurs at full
load (continuous). Determine the continuous rating.
A motor is required to deliver a load which follows the following cycle: 50 kW
for 5 minutes; no load for 4 minutes; 35 kW for 10 minutes; no load for 6
minutes. The cycle is repeated indefinitely. Find the suitable capacity of a
continuously rated motor for the purpose.
The temperature rise of motor after operating for 30 minutes on full load is 15°C
and after another 40 minutes it becomes 20°C on the same load. Find the final
temperature rise and time constant.
Derive the braking toque of DC shunt motors with its diagrams.
A 45kW, 440V dc shunt motor is braked by the plugging. Armature resistance is
0.3 ohm. Full load armature current is 200A and full load speed is 600rpm.
Calculate the value of the resistance to be placed in series with the armature
circuit to limit the corresponding braking torque.
Analyze the motor at running condition and drive the 𝜏 and 𝜃𝑓 state temperature
At full load of 10 H.P., temperature rise of a motor is 20°C after one hour and
30°C after two hours. Find i) The final temperature rise on full load ii) Heating
time constant of motor.
Investigate the DC and AC dynamic braking of three phase induction motor.
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26.
621321114024
621321114025
621321114026
DHANUSHKUMAR E
DHANUSHKUMAR R
DHARANIKUMAR S
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A
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A
2
Calculate the emf of a 4 pole DC motor having 460 conductors and driven
at a speed of 1500 rpm. The flux per pole is 0.015 Wb. Assume the
generator to the (a) lap wound, (b) wave wound.
A wave connected armature winding has 21 slots with 54 conductors per
slot. If the flux per pole is 0.045 Wb and number of pole is 6, find the
speed at which the motor should be run to give 500 V. Also find the
speed if the armature is lap connected.
A
2
Analyze the motor at rest condition and drive the 𝜏 and 𝜃𝑓 state temperature
A
1
In a certain electric drive, the temperature rise is 20°C afterone hour
and35.5°C after two hours, starting from cold conditions. The ambient
temperature is 35°C.
1. Find steady temperature and the heating time constant.
2. When disconnected, the temperature falls from the final steady value
to 45°C in 1.5 hours, calculate the cooling time constant.
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1
A
2
E
2
E
1
Analyze the T-N, T-Ia, N-Ia characteristics of DC shunt motors.
A 4 pole dc motor takes a 25 A armature current. The armature has lap
connected 480 conductors. The flux per pole is 10 mWb. Calculate the gross
torque developed by the armature of the motor.
A 220V, d.c motor has an armature resistance of 0.70Ω. It is during an armature
current of 20A, driving a certain load. Calculate the induced emf in the motor
under this condition.
The 5 minutes rating of a motor used in domestic mixer is 100 watts. The heating
time constant is 40 minutes and the maximum efficiency occurs at full load
(continuous). Determine the continuous rating.
A motor is required to deliver a load which follows the following cycle: 50 kW
for 5 minutes; no load for 4 minutes; 25 kW for 5 minutes; no load for 5 minutes.
The cycle is repeated indefinitely. Find the suitable capacity of a continuously
rated motor for the purpose.
A motor has a thermal heating time constant of 35 minutes. When the motor runs
continuously on full load, its final temperature rises to 95 degree Celsius.
i)What would be the temperature rise after 1 hour, if the motor runs continuously
on full load?
ii)If the temperature rises on 1 hour rating is allowed to be 70 degree Celsius,
find what would be the new steady state temperature at this rating.
Analyze the three regions of 3 phase induction motor T.N characteristics.
Apply double field revolving theory and explain the working of single
phase induction motor.
27.
28.
29.
621321114027
621321114028
621321114029
DHARANIYARASAN R
DHINESH R
DINESH V
Analyze the various drives based on source and industrial applications
At full load of 5 H.P., temperature rise of a motor is 20°C after one hour and
40°C after two hours. Find i) The final temperature rise on full load ii) Heating
time constant of motor.
Derive the braking toque of DC series motors with its diagrams.
A 4 pole d.c motor has lap connected armature winding. The flux per pole is
30mWb. The number of armature conductors is 250. When connected to 230V.
Supply it draws an armature current of 25A. Calculate the back emf and the
speed of with which motor is running. Assume armature resistance is 0.6 Ω.
Classify the different classes of duty with various loads
The enclosure of a 35 kW motor is equivalent to a cylinder of a 70 cm diameter
and 95 cm length. The motor weighs 575 kg. Assuming the specific heat is
780J/kg / °C and that the peripheral surface of the enclosure of the motor alone is
capable of heat dissipation of 14.5 W/sq-m/ °C, calculate the heating time
constant of the motor and its final temperature rise. Efficiency of the motor is 75
%.
Discuss about the DC shunt motor characteristics with different V, Rsh, Ra
Analyze the DC and AC dynamic braking of three phase induction motor.
Discuss about the selection of power rating of dc drives
The 5 minutes rating of a motor used in domestic mixer is 200 watts. The heating
time constant is 40 minutes and the maximum efficiency occurs at full load
(continuous). Determine the continuous rating.
A motor is required to deliver a load which follows the following cycle: 40 kW
for 5 minutes; no load for 4 minutes; 25 kW for 6 minutes; no load for 6 minutes.
The cycle is repeated indefinitely. Find the suitable capacity of a continuously
rated motor for the purpose.
Analyze the plugging, dynamic braking methods of DC series motors.
Calculate the emf of a 6 pole DC motor having 500 conductors and driven
at a speed of 1300 rpm. The flux per pole is 0.012 Wb. Assume the
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generator to the (a) lap wound, (b) wave wound.
A wave connected armature winding has 18 slots with 54 conductors per
slot. If the flux per pole is 0.025 Wb and number of pole is 8, find the
speed at which the motor should be run to give 500 V. Also find the
speed if the armature is lap connected.
30.
31.
32.
621321114030
621321114031
621321114032
DIVAKAR S
ELANCHURIYAN N
GIFTSON VIJAYAKUMAR
J
Discuss about the short time, continuous, intermittent duty with various loads
A motor has a thermal heating time constant of 45 minutes. When the motor runs
continuously on full load, its final temperature rises to 75 degree Celsius.
i)What would be the temperature rise after 1 hour, if the motor runs continuously
on full load?
ii)If the temperature rises on 1 hour rating is allowed to be 70 degree Celsius,
find what would be the new steady state temperature at this rating.
Compare the DC and AC dynamic braking of three phase induction motor.
A 55kW, 440V dc shunt motor is braked by the plugging. Armature resistance is
0.4ohm. Full load armature current is 150A and full load speed is 600rpm.
Calculate the value of the resistance to be placed in series with the armature
circuit to limit the corresponding braking torque.
Discuss about the 12 factors of selection of electrical drives
In a certain electric drive, the temperature rise is 20°C after one hour
and35.5°C after two hours, starting from cold conditions. The ambient
temperature is 35°C.
1. Find steady temperature and the heating time constant.
2. When disconnected, the temperature falls from the final steady value
to 45°C in 2 hours, calculate the cooling time constant.
Analyze the DC shunt and compound motors with voltage equations.
A 2 pole dc motor takes a 25 A armature current. The armature has lap
connected 480 conductors. The flux per pole is 10 mWb. Calculate the gross
torque developed by the armature of the motor.
A 220V, d.c motor has an armature resistance of 0.70Ω. It is during an armature
current of 20A, driving a certain load. Calculate the induced emf in the motor
under this condition.
Based on the rms torque, estimate the kW rating of a 750 r.p.m motor used for
driving equipment having the following load torque curve.
1) For the first 10 seconds, the torque is constant at 40 kg-m.
2) For the next 30 seconds, the torque varies linearly with time from 35 kgm to 15 kg-m.
3) For the last 50 seconds, the torque is constant and equal to 10 kg-m.
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33.
34.
35.
621321114033
621321114035
621321114037
GOKUL A
GOWTHAM B
GURUMOORTHI S
At full load of 5 H.P., temperature rise of a motor is 30°C after one hour and
40°C after two hours. Find i) The final temperature rise on full load ii) Heating
time constant of motor.
Analyze the different types of single phase induction motor.
Analyze the DC and AC dynamic braking of three phase induction motor.
Analyze the short time, continuous, intermittent duty with starting and braking.
The 5 minutes rating of a motor used in domestic mixer is 200 watts. The heating
time constant is 40 minutes and the maximum efficiency occurs at full load
(continuous). Determine the continuous rating.
A motor is required to deliver a load which follows the following cycle: 40 kW
for 5 minutes; no load for 5 minutes; 35 kW for 6 minutes; no load for 6 minutes.
The cycle is repeated indefinitely. Find the suitable capacity of a continuously
rated motor for the purpose.
Derive the torque equation with starting and maximum torque.
A 6 pole, 3 phase, 50 Hz star connected induction motor has a full load slip of
4.5%. Calculate full load speed of the motor.
A three phase induction motor is wound for 6 poles and is supplied from 50Hz
system. Calculate a) the synchronous speed. b) The speed of the motor when
slip is 5.1.
Analyze the short time, continuous, intermittent duty with various loads
A motor has a thermal heating time constant of 35 minutes. When the motor runs
continuously on full load, its final temperature rises to 80 degree Celsius.
i)What would be the temperature rise after 1 hour, if the motor runs continuously
on full load?
ii)If the temperature rises on 1 hour rating is allowed to be 70 degree Celsius,
find what would be the new steady state temperature at this rating.
Apply the induction principle and explain the working of 3 phase induction
motor with effect of slip.
A 50 kW, 440V dc shunt motor is braked by the plugging. Armature resistance is
0.4ohm. Full load armature current is 700A and full load speed is 600rpm.
Calculate the value of the resistance to be placed in series with the armature
circuit to limit the corresponding braking torque.
Based on the rms torque, estimate the kW rating of a 700 r.p.m motor used for
driving equipment having the following load torque curve.
1) For the first 20 seconds, the torque is constant at 40 kg-m.
2) For the next 40 seconds, the torque varies linearly with time from 35 kgm to 15 kg-m.
3) For the last 50 seconds, the torque is constant and equal to 10 kg-m.
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The 15 minutes rating of a motor used in domestic mixer is 200 watts. The
heating time constant is 30 minutes and the maximum efficiency occurs at full
load (continuous). Determine the continuous rating.
A motor is required to deliver a load which follows the following cycle: 40 kW
for 5 minutes; no load for 4 minutes; 20 kW for 6 minutes; no load for 6 minutes.
The cycle is repeated indefinitely. Find the suitable capacity of a continuously
rated motor for the purpose.
Apply two field revolving theory and explain the working of single phase
induction motor.
36.
37.
621321114038
621321114039
HARIHARAN K
(16.05.2004)
HARIHARAN
K(20.06.2004)
A 6 pole d.c motor has lap connected armature winding. The flux per pole is
25mWb. The number of armature conductors is 250. When connected to 230V.
Supply it draws an armature current of 25A. Calculate the back emf and the
speed of with which motor is running. Assume armature resistance is 0.6 Ω.
Analyze the short time, continuous, intermittent duty with starting and braking.
At full load of 10 H.P., temperature rise of a motor is 25°C after one hour and
30°C after two hours. Find i) The final temperature rise on full load ii) Heating
time constant of motor.
Derive the torque equation and relate torque and speed equation of DC motor.
A 4 pole dc motor takes a 35 A armature current. The armature has lap
connected 480 conductors. The flux per pole is 20 mWb. Calculate the gross
torque developed by the armature of the motor.
A 220V, d.c motor has an armature resistance of 0.50Ω. It is during an armature
current of 10A, driving a certain load. Calculate the induced emf in the motor
under this condition.
Based on the rms torque, estimate the kW rating of a 600 r.p.m motor used for
driving equipment having the following load torque curve.
1) For the first 10 seconds, the torque is constant at 40 kg-m.
2) For the next 20 seconds, the torque varies linearly with time from 35 kgm to 15 kg-m.
3) For the last 50 seconds, the torque is constant and equal to 20 kg-m.
The enclosure of a 35 kW motor is equivalent to a cylinder of a 70 cm diameter
and 95 cm length. The motor weighs 560 kg. Assuming the specific heat is
780J/kg / °C and that the peripheral surface of the enclosure of the motor alone is
capable of heat dissipation of 12.5 W/sq-m/ °C, calculate the heating time
constant of the motor and its final temperature rise. Efficiency of the motor is 75
%.
Investigate the stable and unstable regions of T-S characteristics of induction
motor.
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38.
39.
621321114040
621321114041
621321114042
40.
HARISH KUMAR R
HARISH T R
HARISHWAR R
Calculate the emf of a 4 pole DC motor having 500 conductors and driven
at a speed of 1500 rpm. The flux per pole is 0.012 Wb. Assume the
generator to the (a) lap wound, (b) wave wound.
A wave connected armature winding has 18 slots with 60 conductors per
slot. If the flux per pole is 0.025 Wb and number of pole is 86, find the
speed at which the motor should be run to give 500 V. Also find the
speed if the armature is lap connected.
A
2
Analyze the short time, continuous, intermittent duty with starting and braking.
A
1
In a certain electric drive, the temperature rise is 20°C after one hour
and37.5°C after two hours, starting from cold conditions. The ambient
temperature is 35°C.
1. Find steady temperature and the heating time constant.
2. When disconnected, the temperature falls from the final steady value
to 40°C in 2 hours, calculate the cooling time constant.
E
1
A
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2
2
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1
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2
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2
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1
Analyze the three braking methods of DC shunt motors.
Derive the torque equation with starting and maximum torque.
Based on the rms torque, estimate the kW rating of a 600 r.p.m motor used for
driving equipment having the following load torque curve.
4) For the first 10 seconds, the torque is constant at 40 kg-m.
5) For the next 20 seconds, the torque varies linearly with time from 35 kgm to 15 kg-m.
6) For the last 50 seconds, the torque is constant and equal to 20 kg-m.
A motor has a thermal heating time constant of 40 minutes. When the motor runs
continuously on full load, its final temperature rises to 80 degree Celsius.
i)What would be the temperature rise after 1 hour, if the motor runs continuously
on full load?
ii)If the temperature rises on 1 hour rating is allowed to be 70 degree Celsius,
find what would be the new steady state temperature at this rating.
Differentiate the constructional difference of 3 phase squirrel cage and slip ring
induction motor
Analyze the DC and AC dynamic braking of three phase induction motor.
Analyze the various drives based on source and industrial applications
In a certain electric drive, the temperature rise is 20°C afterone hour
and30.5°C after two hours, starting from cold conditions. The ambient
temperature is 35°C.
1. Find steady temperature and the heating time constant.
2. When disconnected, the temperature falls from the final steady value
to 45°C in 1.5 hours, calculate the cooling time constant.
621321114043
INDHIRAN R
41.
621321114044
JAGADESHWARAN M
42.
621321114045
43.
JAHAN M M
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At full load of a 10 H.P the temperature rise of a motor is 25 C after one
hour and 40 C after two hours. Find (1) The final temperature rise on full
load (2) Heating time constant of motor (3) Half hour rating if iron losses
which remain constant are 80% of copper losses at full load.
E
1
Draw and explain counter current and regenerative braking of 3 phase induction
motor.
A
2
Calculate the emf of a 6 pole DC motor having 400 conductors and
driven at a speed of 1500 rpm. The flux per pole is 0.012 Wb. Assume
the generator to the (a) lap wound, (b) wave wound.
A wave connected armature winding has 18 slots with 60 conductors per
slot. If the flux per pole is 0.035 Wb and number of pole is 6, find the
speed at which the motor should be run to give 500 V. Also find the
speed if the armature is lap connected.
A
2
A
1
E
1
Analyze the dynamic braking and plugging of 3 phase induction motor
A 6 pole dc motor takes a 35 A armature current. The armature has lap
connected 480 conductors. The flux per pole is 20 mWb. Calculate the gross
torque developed by the armature of the motor.
A 220V, d.c motor has an armature resistance of 0.50Ω. It is during an armature
current of 30A, driving a certain load. Calculate the induced emf in the motor
under this condition.
Discuss about the four quadrant operation of electrical drives
At full load of 11 H.P., temperature rise of a motor is 25°C after one hour and
35°C after two hours. Find i) The final temperature rise on full load ii) Heating
time constant of motor.
Write the voltage and current equations of DC motors
A 4 pole, 3 phase, 50 Hz star connected induction motor has a full load slip of
3.5%. Calculate full load speed of the motor.
A three phase induction motor is wound for 6 poles and is supplied from 50Hz
system. Calculate a) the synchronous speed. b) The speed of the motor when
slip is 3.5.
Analyze the multi quadrant hoist load with various load conditions
Discuss the short time, continuous, intermittent duty with starting and braking.
The enclosure of a 45 kW motor is equivalent to a cylinder of a 70 cm diameter
and 95 cm length. The motor weighs 560 kg. Assuming the specific heat is
700J/kg / °C and that the peripheral surface of the enclosure of the motor alone is
capable of heat dissipation of 12.5 W/sq-m/ °C, calculate the heating time
621321114046
JAISURYA P
44.
621321114047
KALAIYARASAN E
In a certain electric drive, the temperature rise is 20°C after one hour
and35.5°C after two hours, starting from cold conditions. The ambient
temperature is 35°C.
1. Find steady temperature and the heating time constant.
2. When disconnected, the temperature falls from the final steady value
to 40°C in 1.5 hours, calculate the cooling time constant.
45.
46.
constant of the motor and its final temperature rise. Efficiency of the motor is 75
%.
Discuss about the DC compound motor characteristics with different V, Rsh, Ra
A 40kW, 440V dc shunt motor is braked by the plugging. Armature resistance is
0.4ohm. Full load armature current is 150A and full load speed is 600rpm.
Calculate the value of the resistance to be placed in series with the armature
circuit to limit the corresponding braking torque.
Analyze the four quadrant operation of electrical drives
A motor has a thermal heating time constant of 35 minutes. When the motor runs
continuously on full load, its final temperature rises to 70 degree Celsius.
i)What would be the temperature rise after 1 hour, if the motor runs continuously
on full load?
ii)If the temperature rises on 1 hour rating is allowed to be 70 degree Celsius,
find what would be the new steady state temperature at this rating.
Analyze the stator and rotor constructional difference of single phase induction
motor.
Analyze the dynamic braking and plugging of 3 phase induction motor
The 20 minutes rating of a motor used in domestic mixer is 300 watts. The
heating time constant is 40 minutes and the maximum efficiency occurs at full
load (continuous). Determine the continuous rating.
A motor is required to deliver a load which follows the following cycle: 40 kW
for 5 minutes; no load for 4 minutes; 25 kW for 6 minutes; no load for 6 minutes.
The cycle is repeated indefinitely. Find the suitable capacity of a continuously
rated motor for the purpose.
621321114048
KARAN S
Evaluate the effect of slip reactance , impedance and P.F.
A 6 pole, 3 phase, 50 Hz star connected induction motor has a full load slip of
3.5%. Calculate full load speed of the motor.
A three phase induction motor is wound for 4 poles and is supplied from 50Hz
system. Calculate a) the synchronous speed. b) The speed of the motor when
slip is 3.5.
A motor has a thermal heating time constant of 45 minutes. When the motor runs
continuously on full load, its final temperature rises to 80 degree Celsius.
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621321114049
KARTHICK K
47.
621321114050
48.
KARTHICK S
i)What would be the temperature rise after 1 hour, if the motor runs continuously
on full load?
ii)If the temperature rises on 1 hour rating is allowed to be 75 degree Celsius,
find what would be the new steady state temperature at this rating.
Discuss about the Hoist load 4 types of operation of electrical drives
Investigate the different starters of single phase induction motor.
A 4 pole d.c motor has lap connected armature winding. The flux per pole is
20mWb. The number of armature conductors is 250. When connected to 230V.
Supply it draws an armature current of 20A. Calculate the back emf and the
speed of with which motor is running. Assume armature resistance is 0.6 Ω.
Classify the different load torques with its diagram.
A
A
1
2
E
2
A
1
At full load of a 5 H.P the temperature rise of a motor is 25 C after one
hour and 40 C after two hours. Find (1) The final temperature rise on full
load (2) Heating time constant of motor (3) Half hour rating if iron losses
which remain constant are 80% of copper losses at full load.
E
1
Compare the DC shunt motor characteristics with different V, Rsh, Ra
A
2
Calculate the emf of a 8 pole DC motor having 400 conductors and
driven at a speed of 1500 rpm. The flux per pole is 0.012 Wb. Assume
the generator to the (a) lap wound, (b) wave wound.
A wave connected armature winding has 18 slots with 60 conductors per
slot. If the flux per pole is 0.035 Wb and number of pole is 4, find the
speed at which the motor should be run to give 500 V. Also find the
speed if the armature is lap connected.
A
2
A
1
E
1
A
2
E
2
Analyze the multi quadrant hoist load with various load conditions
The 10 minutes rating of a motor used in domestic mixer is 200 watts. The
heating time constant is 40 minutes and the maximum efficiency occurs at full
load (continuous). Determine the continuous rating.
A motor is required to deliver a load which follows the following cycle: 40 kW
for 5 minutes; no load for 4 minutes; 25 kW for 6 minutes; no load for 6 minutes.
The cycle is repeated indefinitely. Find the suitable capacity of a continuously
rated motor for the purpose.
Analyze the plugging, dynamic braking methods of DC shunt motors.
A 2 pole dc motor takes a 35 A armature current. The armature has lap
connected 480 conductors. The flux per pole is 20 mWb. Calculate the gross
torque developed by the armature of the motor.
A 220V, d.c motor has an armature resistance of 0.50Ω. It is during an armature
current of 30A, driving a certain load. Calculate the induced emf in the motor
621321114051
KARTHIKEYAN D
under this condition.
Analyze the N-T characteristics for different loads with its diagrams.
At full load of a 5 H.P the temperature rise of a motor is 25 C after one
hour and 30 C after two hours. Find (1) The final temperature rise on full
load (2) Heating time constant of motor (3) Half hour rating if iron losses
which remain constant are 80% of copper losses at full load.
49.
621321114052
KATHIRAVAN A
50.
Analyze the DC series motor characteristics with different V, Rsh, Ra
A 30kW, 440V dc shunt motor is braked by the plugging. Armature resistance is
0.4ohm. Full load armature current is 80A and full load speed is 600rpm.
Calculate the value of the resistance to be placed in series with the armature
circuit to limit the corresponding braking torque.
Compare the different load torques with its diagram.
The enclosure of a 45 kW motor is equivalent to a cylinder of a 60 cm diameter
and 95 cm length. The motor weighs 500 kg. Assuming the specific heat is
700J/kg / °C and that the peripheral surface of the enclosure of the motor alone is
capable of heat dissipation of 12.5 W/sq-m/ °C, calculate the heating time
constant of the motor and its final temperature rise. Efficiency of the motor is 80
%.
Compare the capacitor start, capacitor run, and shaded pole methods.
Calculate the emf of a 6 pole DC motor having 450 conductors and driven
at a speed of 1500 rpm. The flux per pole is 0.012 Wb. Assume the
generator to the (a) lap wound, (b) wave wound.
A wave connected armature winding has 22 slots with 70 conductors per
slot. If the flux per pole is 0.045 Wb and number of pole is 86, find the
speed at which the motor should be run to give 550 V. Also find the
speed if the armature is lap connected.
621321114053
KAVINDHAYANITHI K
51.
621321114055
52.
KAVIYARASU M
Draw the curve for temperature reduction and drive its final temperature
Classify the load torques with various load applications.
A 4 pole d.c motor has lap connected armature winding. The flux per pole is
40mWb. The number of armature conductors is 100. When connected to 230V.
Supply it draws an armature current of 15A. Calculate the back emf and the
speed of with which motor is running. Assume armature resistance is 0.6 Ω.
Analyze the different types of DC motors with diagrams.
Classify the different load torques with its diagram.
At full load of a 5 H.P the temperature rise of a motor is 30 C after one
hour and 40 C after two hours. Find (1) The final temperature rise on full
load (2) Heating time constant of motor (3) Half hour rating if iron losses
A
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which remain constant are 80% of copper losses at full load.
621321114056
KIRUTHICROSHAN S
53.
621321114057
KISHORE R
54.
55.
621321114058
KISHORE.S
Investigate the low and high slip regions of T-S characteristics of induction
motor.
A 4 pole, 3 phase, 50 Hz star connected induction motor has a full load slip of
4.5%. Calculate full load speed of the motor.
A three phase induction motor is wound for 6 poles and is supplied from 50Hz
system. Calculate a) the synchronous speed. b) The speed of the motor when
slip is 5.
The 5 minutes rating of a motor used in domestic mixer is 200 watts. The heating
time constant is 40 minutes and the maximum efficiency occurs at full load
(continuous). Determine the continuous rating.
A motor is required to deliver a load which follows the following cycle: 40 kW
for 5 minutes; no load for 4 minutes; 40 kW for 6 minutes; no load for 6 minutes.
The cycle is repeated indefinitely. Find the suitable capacity of a continuously
rated motor for the purpose.
The enclosure of a 45 kW motor is equivalent to a cylinder of a 60 cm diameter
and 100 cm length. The motor weighs 700 kg. Assuming the specific heat is
700J/kg / °C and that the peripheral surface of the enclosure of the motor alone is
capable of heat dissipation of 12.5 W/sq-m/ °C, calculate the heating time
constant of the motor and its final temperature rise. Efficiency of the motor is
90%.
Compare the types starting methods of single phase induction motor.
A
2
A
2
E
1
E
1
A
2
Calculate the emf of a 8 pole DC motor having 450 conductors and driven
at a speed of 1400 rpm. The flux per pole is 0.012 Wb. Assume the
generator to the (a) lap wound, (b) wave wound.
A wave connected armature winding has 22 slots with 70 conductors per
slot. If the flux per pole is 0.035 Wb and number of pole is 86, find the
speed at which the motor should be run to give 550 V. Also find the
speed if the armature is lap connected.
A
2
Draw the curve for temperature reduction and drive its final temperature
A
1
At full load of a 10 H.P the temperature rise of a motor is 30 C after one
hour and 40 C after two hours. Find (1) The final temperature rise on full
load (2) Heating time constant of motor (3) Half hour rating if iron losses
which remain constant are 80% of copper losses at full load.
E
1
Evaluate the effect of slip rotor current and P.F.
Analyze the DC and AC dynamic braking of three phase induction motor.
Analyze the N-T characteristics for different loads with its diagrams.
E
A
A
2
2
1
621321114059
KUMARAGURU R
At full load of a 10 H.P the temperature rise of a motor is 30 C after one
hour and 40 C after two hours. Find (1) The final temperature rise on full
load (2) Heating time constant of motor (3) Half hour rating if iron losses
which remain constant are 80% of copper losses at full load.
56.
621321114060
KUMARAN T
57.
621321114061
58.
Analyze the multi quadrant hoist load with various load conditions
Draw the characteristics of induction motor and compare motoring, generating,
braking regions.
Analyze the DC series motor characteristics with different V, Rsh, Ra
The 10 minutes rating of a motor used in domestic mixer is 200 watts. The
heating time constant is 40 minutes and the maximum efficiency occurs at full
load (continuous). Determine the continuous rating.
A motor is required to deliver a load which follows the following cycle: 40 kW
for 5 minutes; no load for 5 minutes; 30 kW for 6 minutes; no load for 6 minutes.
The cycle is repeated indefinitely. Find the suitable capacity of a continuously
rated motor for the purpose.
LOGESHWARAN V
Compare dynamic braking and plugging of DC shunt motor.
A 2 pole, 3 phase, 50 Hz star connected induction motor has a full load slip of
4.5%. Calculate full load speed of the motor.
A three phase induction motor is wound for 4 poles and is supplied from 50Hz
system. Calculate a) the synchronous speed. b) The speed of the motor when
slip is 5.
Analyze the N-T characteristics for different loads with its diagrams.
Analyze the running condition motor and derive the heat rise
Derive the torque equation and relate torque and speed equation of DC motor.
A 35kW, 440V dc shunt motor is braked by the plugging. Armature resistance is
0.5ohm. Full load armature current is 80A and full load speed is 600rpm.
Calculate the value of the resistance to be placed in series with the armature
circuit to limit the corresponding braking torque.
Analyze the rest condition motor and derive the heat reduction
The enclosure of a 50 kW motor is equivalent to a cylinder of a 60 cm diameter
and 100 cm length. The motor weighs 700 kg. Assuming the specific heat is
600J/kg / °C and that the peripheral surface of the enclosure of the motor alone is
capable of heat dissipation of 12.5 W/sq-m/ °C, calculate the heating time
constant of the motor and its final temperature rise. Efficiency of the motor is
95%.
Discuss the T-N, T-Ia, N-Ia characteristics of DC shunt motors.
Analyze the different starters of single phase induction motor.
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621321114062
LOKESH KUMAR K
Analyze the speed torque characteristics for different loads with its diagrams.
Draw the curve for temperature reduction and drive its final temperature
Compare the stator and rotor constructional difference of single phase induction
motor.
Calculate the emf of a 4 pole DC motor having 450 conductors and driven
at a speed of 1300 rpm. The flux per pole is 0.012 Wb. Assume the
generator to the (a) lap wound, (b) wave wound.
A wave connected armature winding has 22 slots with 70 conductors per
slot. If the flux per pole is 0.025 Wb and number of pole is 86, find the
speed at which the motor should be run to give 550 V. Also find the
speed if the armature is lap connected.
59.
621321114063
MADHAN KUMAR V
Analyze the heating and cooling curves with tis diagrams
The heating and cooling time constants of an electric motor are 100 and 150
minutes respectively. The rating of the motor is 125 kW. If it is working on duty
cycle of 15 minutes on load and 30 minutes on no load, determine the
permissible overloading of the motor. Assume the losses are given by the
𝑃
expression 𝑃𝐶 + 𝑥 2 𝑃𝑐𝑢 𝑎𝑛𝑑 𝑐 = 𝛼 = 0.4.
𝑃𝑐𝑢
1
1
A
2
A
2
A
1
E
1
A
2
E
2
A
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Ap
2
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A constant speed drive operating at a speed of 500 r.p.m has a cyclic loading as
given below: 200 Nm for 10 minutes, 300 Nm for 20 minutes, 150 Nm for 20
minutes and No load for 10 minutes. Estimate power rating of the rotor.
60.
2022LME01
BALAJI S
Discuss the T-N, T-Ia, N-Ia characteristics of DC series motors.
A 4 pole d.c motor has lap connected armature winding. The flux per pole is
20mWb. The number of armature conductors is 100. When connected to 230V.
Supply it draws an armature current of 10A. Calculate the back emf and the
speed of with which motor is running. Assume armature resistance is 0.5 Ω.
Discuss about the speed torque characteristics for different loads with its
diagrams.
At full load of a 10 H.P the temperature rise of a motor is 20 C after one
hour and 30 C after two hours. Find (1) The final temperature rise on full
load (2) Heating time constant of motor (3) Half hour rating if iron losses
which remain constant are 85% of copper losses at full load.
Apply capacitors and switches and design two types of single phase
induction motor starters.
61.
62.
A
A
2022LME02
DEV ARUN A V G
Compare dynamic braking and plugging of DC shunt motor.
Analyze the heating and cooling curves with tis diagrams
The heating and cooling time constants of an electric motor are 200 and 250
minutes respectively. The rating of the motor is 125 kW. If it is working on duty
cycle of 15 minutes on load and 30 minutes on no load, determine the
permissible overloading of the motor. Assume the losses are given by the
𝑃
expression 𝑃𝐶 + 𝑥 2 𝑃𝑐𝑢 𝑎𝑛𝑑 𝑃 𝑐 = 𝛼 = 0.4.
𝑐𝑢
E
1
A
2
A
2
E
1
A
A
1
2
A
2
A
1
E
1
A
2
A constant speed drive operating at a speed of 400 r.p.m has a cyclic loading as
given below: 200 Nm for 10 minutes, 300 Nm for 20 minutes, 150 Nm for 20
minutes and No load for 10 minutes. Estimate power rating of the rotor.
2022LME03
HARIHARAN G
Analyze the capacitor -start capacitor-run starter of induction motor
Calculate the emf of a 6 pole DC motor having 400 conductors and driven
at a speed of 1600 rpm. The flux per pole is 0.014 Wb. Assume the
generator to the (a) lap wound, (b) wave wound.
A wave connected armature winding has 22 slots with 80 conductors per
slot. If the flux per pole is 0.025 Wb and number of pole is 86, find the
speed at which the motor should be run to give 450 V. Also find the
speed if the armature is lap connected.
63.
2022LME04
64.
Compare dynamic braking and plugging of DC series motor.
A 2 pole, 3 phase, 50 Hz star connected induction motor has a full load slip of
3%. Calculate full load speed of the motor.
A three phase induction motor is wound for 6 poles and is supplied from 50Hz
system. Calculate a) the synchronous speed. b) The speed of the motor when
slip is 4.1.
The enclosure of a 55 kW motor is equivalent to a cylinder of a 60 cm diameter
and 90 cm length. The motor weighs 700 kg. Assuming the specific heat is
700J/kg / °C and that the peripheral surface of the enclosure of the motor alone is
capable of heat dissipation of 12.5 W/sq-m/ °C, calculate the heating time
constant of the motor and its final temperature rise. Efficiency of the motor is
90%.
Analyze the heating and cooling curves with tis diagrams
ASWINKUMAR P
Discuss about the speed torque characteristics for different loads with its
diagrams.
At full load of a 5 H.P the temperature rise of a motor is 20 C after one
hour and 30 C after two hours. Find (1) The final temperature rise on full
load (2) Heating time constant of motor (3) Half hour rating if iron losses
which remain constant are 90% of copper losses at full load.
Compare the different rotors of 3 phase induction motor.
2022LME05
BARATHKUMAR K
65.
A 6 pole d.c motor has lap connected armature winding. The flux per pole is
20mWb. The number of armature conductors is 200. When connected to 230V.
Supply it draws an armature current of 30A. Calculate the back emf and the
speed of with which motor is running. Assume armature resistance is 0.5 Ω.
Analyze the various drives based on source and industrial applications
The enclosure of a 45 kW motor is equivalent to a cylinder of a 60 cm diameter
and 100 cm length. The motor weighs 700 kg. Assuming the specific heat is
600J/kg / °C and that the peripheral surface of the enclosure of the motor alone is
capable of heat dissipation of 12.5 W/sq-m/ °C, calculate the heating time
constant of the motor and its final temperature rise. Efficiency of the motor is
90%.
A 55kW, 440V dc shunt motor is braked by the plugging. Armature resistance is
0.6ohm. Full load armature current is 90A and full load speed is 600rpm.
Calculate the value of the resistance to be placed in series with the armature
circuit to limit the corresponding braking torque.
Compare the starting characteristics of single phase induction motor.
Analyze the various drives based on source and industrial applications
Draw and compare counter current and regenerative braking of 3 phase induction
motor.
A 6 pole, 3 phase, 50 Hz star connected induction motor has a full load slip of
5%. Calculate full load speed of the motor.
A three phase induction motor is wound for 6 poles and is supplied from 50Hz
system. Calculate a) the synchronous speed. b) The speed of the motor when
slip is 4.1.
Faculty In-charge
Co-ordinator
HOD
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