0
Deduce an expression for the torque develop by the armature of a dc motor?
Wiki User
∙ 14y ago
he magnitude of torque depends on three quantities: First, the force applied; second, the length of the lever arm[4] connecting the axis to the point of force application; and third, the angle between the two. In symbols:
whereτ is the torque vector and τ is the magnitude of the torque,r is the displacement vector (a vector from the point from which torque is measured to the point where force is applied), and r is the length (or magnitude) of the lever arm vector,F is the force vector, and F is the magnitude of the force,× denotes the cross product,θ is the angle between the force vector and the lever arm vector.
Wiki User
∙ 14y ago
Add your answer:
Earn +20 pts
What is base speed?
The base speed of a DC motor is the speed at which it operates while delivering rated torque with rated armature voltage and field current applied.
What is the standard torque of a car?
Torque (Nm)
What is breakaway torque?
The torque required to start a machine
Full load torque of induction motor?
full load torque is the torque which produces rated power at full speed
What human body part may produce torque?
Any time there is a force, there can be torque.
How is torque produced in a dc motor?
torque = force x Radius of the armature
What is the effect of field current on dc motor?
The field current of a dc motor provides the magnetic field that allows the motor to develop a torque when current flows through the armature..
Why DC suuply used in Excitation of Alternator?
for torque improvement in armature and create n-pole or s-pole in armature a dc source is used in alternator armature.
Operation of DC generator?
1) PRINCIPLE:Whenever a conductor cuts magnetic flux, dynamically induced emf is produced in it. ( Faraday's Laws of Electromagnetic Induction ). This emf causes a current to flow if the conductor circuit is closed.2 ) OPERATION:Field winding produces magnetic field in D.C. generator. Armature is coupled to the prime mover. Prime mover produces torque so the armature rotates. The armature cuts the magnetic field so the emf is induced in the armature. When load is connected to the armature, electric current flows from the armature conductors, through load and back to the armature conductors. Now, as current flows through the armature and it is in the magnetic field, torque is produced due to it. (This torque is called back torque). If the load on the generator is increased, the back torque increases so the torque of the prime mover also increases and the input power to the prime mover increases. In this way, the generator converts mechanical energy into electrical energy.It should be observed that the emf induced in D.C. generator, is A.C. ( so the emf induced in the armature is alternating in nature. ). Then with the help of commutator, it is converted into D.C. Rings and brushes are used to take the emf outside.
Why the induction motor does not have armature reaction?
Because the armature (or rotor) has no external connection. The currents that produce torque from the rotor are induced by the magnetic field in the machine, so there is no commutator, no brushes and no armature reaction.
How will the armature current and the output power of a dc shunt motors change with increasing load?
With increasing torque load the armature tends to slow down; the motor draws more current to compensate, and if there is armature resistance the back emf generated by the armature falls to allow the increased current to flow, which causes the motor to settle at a lower speed. The mechanical output power is the speed times the torque, and increasing the torque increases the power output provided the speed does not drop much.
Would a DC motor turn if only the armature were supplied DC voltage?
if there are magnets on the stator and the commutator is phased properly this is known as a permanent magnet dc motor the starting torque is dependent on armature current and the strength of the magnet the speed is directly proportional to the armature voltage a shunt motor needs the field energized for starting. more field more starting torque
What role does the armature do in a DC motor?
One of the role of the armature in the DC motor is to carry the current that is crossing the field. By carrying the current crossing the field, it creates the shaft torque in the rotating machine.
How can i control the torque of the wiper motor?
there three connections of armature circuit possible in wiper motors. by changing these arrangments, we can control the speed as well as the torque of any wiper motor.
What is the maximum torque than an induction motor can develop known as?
Gross Torque
What is shunt and series motor?
A series motor is one in which the field windings are in series with the armature windings. So the torque is proportional to the square of the supply current.'Shunt' is an archaic term for 'parallel'. So a shunt motor is one in which the field winding is in parallel with the armature windings. So the torque is proportional to the supply current.
Why it is an advantage for armature to rotate in radial magnetic field rather than uniform?
1.maximum torque is experienced 2.torque is uniform for all positions of coil
