Difference between AC and DC Motors


There are two main types of electric motors. There are direct current or DC and alternating current or AC motors. The reference of DC or AC refers to how the electrical current is transferred through and from the motor.Difference between AC and DC Motors somewhat lies in the name as their name reflect their working style.
Electric Motor:-
It is an electrical device which convert the electrical energy into the mechanical energy. It may be broadly classified into the two types AC motor and the DC motor depending on the type of input used.

DC Motors:-

 A direct current or DC motor, converts electrical energy into mechanical energy and works on Direct current(DC).Among DC motors, there are shunt-wound, series-wound,compound-wound and permanent magnet motors.DC motors come in two general types. They can have brushes or be brushless.

AC Motors:-

 A current or AC motor, converts electrical energy into mechanical energy and works on alternate current(AC).AC also comes in two type. They can be two phase or three phase.

Types of AC and DC Motors:-The two main kind of DC motors are:-

DC motors with brushes: This particular motor is capable of generating a swinging current in the armature or the wound rotor using a split ring commutator ore a magnet stator. 
DC motors without brushes: In this motor there is a mechanical rotating switch or external electronic switch placed just in the motor’s place.
The two main kind of AC motors are:-
 The synchronous AC motors: It starts rotating just when a sub-multiple of the supply frequency or the supply frequency hits. The rotor magnetic field is the result of slip ring current or some permanent magnet.
The induction AC motors: This one turns a little slower than the standard supply frequency. The magnetic field on the rotor in this case works with the help of induced current.
DC motors are self starting and require no external help whereas AC motors effective starting equipment to start operation.Direct current or DC electric motors work for situations where speed needs to be controlled. DC motors have a stable and continuous current. DC motors were the first and earliest motors used. They were found, however, to not be as good at producing power over long lengths DC motors are single phase motors whereas AC motors are both 1 and 3 phase.Though both DC and AC motors work on the same principle of armature winding and magnetic field yet in the former the armature rotates while the magnetic field remains stationary, whereas in AC motors the armature remains stationary and the magnetic field keeps rotating.DC motors generally are more complex than AC motors. This is due to the fact that they need coils and brushes to keep the current constant. DC electric motors are an important part of everyday life, from batteries to DVD players, people use them everyday.

Difference between AC and DC Motors

While the A.C. and D.C. they fulfill the same function of converting electrical energy into mechanical energy, they are fed, constructed and controlled in a different way. The most basic difference is the power source. A.C. engines they are powered by alternating current (A.C.) while the D.C. They receive direct current (D.C.), such as batteries, power supplies D.C. or a AC-DC power converter. The D.C field motors are built with brushes and a commutator, which add to the maintenance, limit the speed and generally reduce the life expectancy of the D.C. brushed. A.C. the induction motors do not use brushes; They are very resistant and have a long life expectancy. The final basic difference is speed control. The speed of a motor D.C. it is controlled by varying the winding current of the armature, while the speed of an A.C. it is controlled by varying the frequency, which is commonly done with an adjustable frequency control control.
1.DC motors are direct current motors while ac motors are alternating current motors.
2.DC motors generally characterize a continual and standard current flow while AC motors are used in variant situations irrespective of the quality of the current flow.
3. DC motors are single phase motors whereas AC motors are both 1 and 3 phase.
4.DC motors are self starting whereas AC motors require effective starting equipment.
5.Direct current or DC electric motors work for situations where speed needs to be controlled.
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