Speed control of D.C Motors (Shunt type)
D.C shunt motor speed can be controlled by the following methods:
i. Flux control method.
ii. Armature control method.
iii. Voltage control method.
N a 1/F ; By decreasing flux, speed can be increased and vice – versa. The
flux of DC motor can be changed by changing the field current with the help
of shunt field rheostat.
N a (V-Ia Ra), The speed / armature current characteristics show that greater
the resistance in armature circuit , greater fall in speed.
Shunt field of motor is connected permanently to a fixed exciting voltage, but
armature is supplied with different voltages by connecting it across one of the
several different voltage by means of suitable switchgear.
gregorymasila answered the question on February 20, 2018 at 16:26
-
Where are synchronous motors used?
(Solved)
Where are synchronous motors used?
Date posted:
February 20, 2018
.
Answers (1)
-
What are the essential differences between H.V. and L.V. switchgears?
(Solved)
What are the essential differences between H.V. and L.V. switchgears?
Date posted:
February 20, 2018
.
Answers (1)
-
Why are different levels of voltages used for generation, transmission and
distribution of electric power?
(Solved)
Why are different levels of voltages used for generation, transmission and
distribution of electric power?
Date posted:
February 20, 2018
.
Answers (1)
-
Explain principle of carrier current protection and communication.
(Solved)
Explain principle of carrier current protection and communication.
Date posted:
February 20, 2018
.
Answers (1)
-
Discuss the criteria for choice of voltage for transmission and distribution.
(Solved)
Discuss the criteria for choice of voltage for transmission and distribution.
Date posted:
February 20, 2018
.
Answers (1)
-
Write short notes on Induction heating:
(Solved)
Write short notes on Induction heating:
Date posted:
February 20, 2018
.
Answers (1)
-
Discuss methods of laying underground cables.
(Solved)
Discuss methods of laying underground cables.
Date posted:
February 20, 2018
.
Answers (1)
-
Explain the working of nickel cadmium cells with its merits and demerits over lead acid cell
(Solved)
Explain the working of nickel cadmium cells with its merits and demerits over lead acid cell
Date posted:
February 20, 2018
.
Answers (1)
-
What are the advantages of high voltage transmission? Give its limitations also.
(Solved)
What are the advantages of high voltage transmission? Give its limitations also.
Date posted:
February 20, 2018
.
Answers (1)
-
List the advantages of nuclear power plants over conventional thermal power plants.
(Solved)
List the advantages of nuclear power plants over conventional thermal power plants.
Date posted:
February 20, 2018
.
Answers (1)
-
What is the fundamental difference between thermal and nuclear power plants?
(Solved)
What is the fundamental difference between thermal and nuclear power plants?
Date posted:
February 20, 2018
.
Answers (1)
-
What are different welding controls used in resistance welding?
(Solved)
What are different welding controls used in resistance welding?
Date posted:
February 20, 2018
.
Answers (1)
-
With the aid of sketches explain the operation of a four stroke engine
(Solved)
With the aid of sketches explain the operation of a four stroke engine.
Date posted:
February 16, 2018
.
Answers (1)
-
Name 3 drawing instruments commonly used in technical drawing and define the use of each tool
(Solved)
Name 3 drawing instruments commonly used in technical drawing and define the use of each tool
Date posted:
January 26, 2018
.
Answers (1)
-
Highlight different methods of water treatment.
(Solved)
Highlight different methods of water treatment.
Date posted:
January 15, 2018
.
Answers (1)
-
Name any five factors which determine choice of roof structure
(Solved)
Name any five factors which determine choice of roof structure.
Date posted:
January 1, 2018
.
Answers (1)
-
Give five functional requirements of foundations
(Solved)
Give five functional requirements of foundations.
Date posted:
January 1, 2018
.
Answers (1)
-
Explain how to test for silt content in sand.
(Solved)
Explain how to test for silt content in sand.
Date posted:
January 1, 2018
.
Answers (1)
-
List five causes of unsealing of traps
(Solved)
List five causes of unsealing of traps.
Date posted:
January 1, 2018
.
Answers (1)
-
State 5 principles of a good drainage system.
(Solved)
State 5 principles of a good drainage system.
Date posted:
January 1, 2018
.
Answers (1)