Without a mechanical load the motor accelerates until the back-emf generated by the armature nearly equals the supply voltage. On load, the speed drops and the current rises until the power taken from the supply balances the mechanical power supplied to the load.
If the armature has low resistance, the speed drop under load is not very much, so speed regulation is better if the armature resistance is lower.
as a motor armature speed increases,the net current in the motor windings decreases due to MAGNETIC DRAG. which is a common phenomenon in the ac machines.
Armature current is the current flowing in a motor's armature. The "armature" is another name for the coil (or coils) of wire which are on the motor's "rotor", which is the part that rotates inside its stator. (The "stator" is the fixed, non-rotating part of the motor.)
since torque is proportional to flux and armature current . Flux for dc shunt is constant . torque is proportional to armature current only. And initially armature current is very low hence it cannot be started at load .
when a dc motor armature current is fluctuated in a range then it is call hunting in a d.c motor.
Armature reaction is the interaction between the magnetic flux produced by armature current and that of the main magnetic field in an electric motor or generator.
as a motor armature speed increases,the net current in the motor windings decreases due to MAGNETIC DRAG. which is a common phenomenon in the ac machines.
Increasing flux, torque of the dc motor will be increased and speed of the dc motor will be decreased as speed of the dc motor is inversely proportional to that of the flux and the torque of the dc motor is directly proportional to the flux.
Armature current is the current flowing in a motor's armature. The "armature" is another name for the coil (or coils) of wire which are on the motor's "rotor", which is the part that rotates inside its stator. (The "stator" is the fixed, non-rotating part of the motor.)
In v curves armature current decreases in under excitation and increase in overexcitation as fielcurrent increases and armature current is maximum at unity power factor.The power is maximum when load angle is equal to impedance angle.A linear motor is a essentially a multi phase
commutator, armature
since torque is proportional to flux and armature current . Flux for dc shunt is constant . torque is proportional to armature current only. And initially armature current is very low hence it cannot be started at load .
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.
To deliver the current to the rotating armature
when a dc motor armature current is fluctuated in a range then it is call hunting in a d.c 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..
Armature reaction is the interaction between the magnetic flux produced by armature current and that of the main magnetic field in an electric motor or generator.
The terms 'shunt' and 'armature' apply to a particular type of d.c. motor, in which the field windings are connected in parallel with the armature windings. 'Shunt' is an archaic term for 'parallel', so the term 'shunt', in this context, means that the field winding is connected in parallel with the armature winding. The terms 'shunt current' and 'armature current', then describe the currents flowing in the shunt winding and armature winding, respectively.