Electric DC Motor (NCC For Matric A1)

INTRODUCTION:

An Electric motor is a device which produces Mechanical output onthe cost of Electrical input in the form of DC.

CONSTRUCTION:

v  STATOR

Source magnet (Natural/ Electromagnet)

v  ROTOR

Ø  Armature:

Laminated Iron protection to reduce magnetization losses

              i.        Rectangular Coil:

Experiences Torque under DC supply

            ii.        Commutator:

Inverts the direction of current in order to continue unidirectional rotation.

·         (C shaped ) Split rings:

Provide blockage way to reverse current’s direction in the coil.

·         Carbon brushes:

Conducts Electricity b/w circuit and Split rings.

           iii.        Shaft:

Produce mechanical output..

Ø  DC Voltage supply:

Input Source for Electrical energy in DC mode.

WORKING:

                      i.        Play the clip above….

                    ii.        See in the clip, Eek rectangular coil ABCD ko hum ne DC Source se jorra hai, current will follows from A to B , B to C , then C to D and D to A, and then to the battery…

                   iii.        Rod AB and CD force experiences karenge jub woh Source magnet ki magnetic field me hon (practically an Electromagnet).

                   iv.        AB pe downward (Current into the page) aur CD pe upwad (Current out of the page)force lage gi.

                    v.        Ye forces equal and opposite hongi ,but they will not cancel each other according to Newton’s Law, because they have different line of actions (bole to… donu not acting on a same point).

                   vi.        In forces ki wajah se, the coil will rotate, let’s say clockwise (I assumed it to make you understand).

                  vii.        Jub coil straight perpendicular to the magnetic field hojae gi, then, Slip rings circuit ko open kar dengi, yaani koi current flow nahi kare ga…..

                viii.        Coil is situation me inertia ki wajah se rotate hogi in the same direction which I had recently assumed (yani clockwise).

                   ix.        Par jese hi ye coil puri tarhan se rotate ho jae gi, to AB ki jagah CD aur CD ki jagah AB aa jae ga then note karo:

Current will flow from D to C , then C to B , then B to A and to the battery….rite???

                    x.        Sawal???? Is se kia faida???

                   xi.        Socho agar current ka direction wohi rehta , yani A se B se C se D, then forces uss k rotation ko anticlockwise kar deti……(use a diagram, paper lo, AB me out of the page current k lye force nikalo aur CD k lye into the page, dekho kese rotate hui??)

                  xii.        Iss wajah se , yani coil ko ek hi direction me ghumane k le hum current ko ulta flow kara dete hain (D se C se B se A) by using a Commutator.

                xiii.        Iss se forces ki direction bhi ulti hojati hain….

                xiv.        Jahan , pehle who forces coil ko clockwise ghumne se rok rahi theen, ab wohi foces use mazeed clock wise ghumaengi….

                  xv.        Iss tarhan se Current ki direction ko adjust karna k who ek hi direction me coil ko ghummae, COMMUTATION kehlata hai….

                xvi.        Now , in this manner coil sirf clock wise move kare gi.

               xvii.         hum kisi mechanical device ko output shaft se jor denge…. (for example, fan or blades)

              xviii.        So simply we converted DC electrical energy into Mechanical energy…jo k function hai Motor ka….

                xix.        SUBHANALLAH !!!