A c generators : A c generators ORIGINS : ORIGINS Designed by a Yugoslav scientist—
Nikola Tesla ELECTRICAL MACHINES : ELECTRICAL MACHINES MACHINEdevice that uses energy to perform some work : MACHINEdevice that uses energy to perform some work ELECTRICAL MACHINE A C GENERATOR : A C GENERATOR Also called dynamo or ALTERNATOR
It converts one form of energy into another that is Mechanical to Electrical
It operates through the interaction between a Magnetic field & a coil
Its an application of the phenomenon of :
ELECTROMAGNETIC INDUCTION CONSTRUCTION : CONSTRUCTION PARTS : PARTS ARMATURE
It consists of a large number of turns of insulated copper wire wound over a laminated soft Iron Core MAGNETS : MAGNETS N & S are the pole pieces of a strong electromagnet in which the armature coil is rotated.
There are two Hollow Metallic rings. To them are connected the 2 ends of armature coil.
These rings rotate with the rotation of the coil. Slide 9: BRUSHES
There are two flexible metal plates or carbon rods.
They are fixed and are kept in light contact with the slip rings.
They are used to pass on current from the armature coil. PRINCIPLE : PRINCIPLE Its working principle is :
It is the phenomena of generating current/e.m.f
by changing the number of Magnetic lines of force associated with a conductor. Magnetic flux(ø) ø=B.A =B.A Cos O : Magnetic flux(ø) ø=B.A =B.A Cos O SI UNIT:Weber
Change in Magnetic lines of force= Change in magnetic flux= An e.m.f is induced=a current is induced FARADAY’S LAWS OF E.M.I : FARADAY’S LAWS OF E.M.I Ist LAW
Whenever the amount of magnetic flux linked with a circuit changes, an e.m.f is induced in the circuit. 2nd LAW : 2nd LAW The magnitude of e.m.f induced in a circuit is directly proportional to the rate of change of magnetic flux linked with the circuit
e =-dø/dt A GENERATOR : A GENERATOR A