how alternator works ?

Answer 1

there are two stator coil one stator has a rectifying ckt thru which the out put voltage is rectified and used to excite the other stator
when the rotor is rotated using prime mover voltage is induced across the stator terminals

Answer 2

Alternators generate electricity by the same principle as DC generators, namely, when the magnetic field around a conductor changes, a current is induced in the conductor. Typically a rotating magnet called the rotor turns within a stationary set of conductors wound in coils on an iron core, called the stator. The field cuts across the conductors, generating an electrical current, as the mechanical input causes the rotor to turn.

The rotor magnetic field may be produced by induction (in a "brushless" alternator), by permanent magnets (in very small machines), or by a rotor winding energized with direct current through slip rings and brushes. The rotor magnetic field may even be provided by stationary field winding, with moving poles in the rotor. Automotive alternators invariably use a rotor winding, which allows control of the alternator generated voltage by varying the current in the rotor field winding. Permanent magnet machines avoid the loss due to magnetizing current in the rotor, but are restricted in size, owing to the cost of the magnet material. Since the permanent magnet field is constant, the terminal voltage varies directly with the speed of the generator. Brushless AC generators are usually larger machines than those used in automotive applications.

A rotating magnetic field is a magnetic field which periodically changes direction. Up until the identification of this concept, generators, such as the homopolar generator and Gramme dynamo, operated by continually passing a conductor through a stationary magnetic field. The key principles of the rotating magnetic field to the operation of alternating-current motor allowed the magnetic field to rotate. In 1882, Nikola Tesla identified the concept of the rotating magnetic field. Tesla had earlier suggested that the commutators from the generator could be removed and the machine could operate on a rotary field of force.

Answer 3

An alternator is an electromechanical device that converts mechanical energy to alternating current electrical energy. Most alternators use a rotating magnetic field but linear alternator are occasionally used. In principle, any AC generator can be called an alternator, but usually the word refers to small rotating machines driven by automotive and other internal combustion engines.

Theory of operation

Alternators generate electricity by the same principle as DC generators, namely, when the magnetic field around a conductor changes, a current is induced in the conductor. Typically a rotating magnet called the rotor turns within a stationary set of conductors wound in coils on an iron core, called the stator. The field cuts across the conductors, generating an electrical current, as the mechanical input causes the rotor to turn.

The rotor magnetic field may be produced by induction (in a "brushless" alternator), by permanent magnets (in very small machines), or by a rotor winding energized with direct current through slip rings and brushes. The rotor magnetic field may even be provided by stationary field winding, with moving poles in the rotor. Automotive alternators invariably use a rotor winding, which allows control of the alternator generated voltage by varying the current in the rotor field winding. Permanent magnet machines avoid the loss due to magnetizing current in the rotor, but are restricted in size, owing to the cost of the magnet material. Since the permanent magnet field is constant, the terminal voltage varies directly with the speed of the generator. Brushless AC generators are usually larger machines than those used in automotive applications.

A rotating magnetic field is a magnetic field which periodically changes direction. Up until the identification of this concept, generators, such as the homopolar generator and Gramme dynamo, operated by continually passing a conductor through a stationary magnetic field. The key principles of the rotating magnetic field to the operation of alternating-current motor allowed the magnetic field to rotate. In 1882, Nikola Tesla identified the concept of the rotating magnetic field. Tesla had earlier suggested that the commutators from the generator could be removed and the machine could operate on a rotary field of force.

Answer 4

According to Faraday's law of electromagnetic induction when a conductor cuts magnetic field, e.m.f is induced in the conductor. Alternator works on same princple. When mechanical energy is given to the alternator, the rotor of the alternator cuts the magnetic field produced due to current flowing in the stator winding.

Answer 5

Alternator works on electromagnetic theory.In this theory,when a conductor moves in magnetic field , a emf gen rate in the conductor . An alternator have a stater and a rotter ,stater are made with copper coils and iron blades which are punched ech other and these blades provide slot for Cu coil.Rotter is a rotating part it is made with Alnico and wrapped with coil in this coil DC current flows thus Rotter is works as magnet.

Answer 6

Read it here

http://en.wikipedia.org/wiki/Alternator