Sunday, 18 January 2015

basis of DC MOTOR

today I am going to discuss on the basic structure and the principle of DC motor,
what is a motor - actually motor is a electrical device that converts electricity into mechanical power,
A DC motor runs only on DC current, if we put a DC motor to AC power supply it starts to vibrate with the frequency of the supply.
basic parts of a DC motor - it has mainly a stator coil, a rotor coil wounded on the motor shaft, and the frame of the motor called yoke,
in household purpose this type of motor is not used, but in large industrial purpose it is till used,  you may see a little model of DC motor in toys (made in China). one interesting thing about this small motor is that you can listen music using this motor as a speaker,  you don't believe it?  just put the wires to the CD DVD OR AMPLIFIER,  and listen the music with a special bass tune  ,
let's discuss on "how it works "
we all aware about the electromagnetic induction, (if a wire is wounded on a magnetic core,when the current passes through the wire, it behaves like a permanent magnet,).  in a DC motor there is a stator winding inside the yoke,  in some special cases a permanent magnet is placed instead of stator windings. a DC power supply is applied on the stator winding that makes it a magnet, and also a power supply is given to the rotor that makes it a magnet,  as we all know that the same pole of two magnet deflects each other,  as the polarity of the stator is static constant, for keeping the balance the rotor moves slightly ,  as the power supply is given to the rotor by a brush contact do the deflection action happens continually and the rotor rotates  ,