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AC and DC Generator

In this article, we study about ac and dc generator, ac and dc generator diagram, ac and dc generator applications and more.

AC Generator

Generators that convert mechanical energy to electrical energy are known as AC generators. An alternating current generator produces alternating current. Alternating currents change the direction of flow at a regular interval.

Mechanical energy can be obtained from a variety of sources.            

After that, the mechanical energy is transformed into electrical energy. Wind turbines, steam turbines, water turbines, and gas turbines are all common mechanical energy sources. The energy source should be huge enough to provide energy to thousands of people.

An electric motor is the polar opposite of an electric generator. Water pumps, electric saws, and other such items are examples.

AC Generator Diagram

Components of AC Generator

The following are the parts of an AC generator:

  • Armature: The component of the generator that produces current is the armature. The armature must be large enough to handle the large current generated by the generator. It is made up of coils of conducting material in most cases.

  • The component that causes the conductor to revolve inside the magnetic field is known as the prime mover. Instead of rotating the conductor, some generators rotate the magnetic field. The result is identical. Any desirable energy source, such as a steam turbine or a wind turbine, can power the prime mover.

  • The stator is the generator’s stationary component. The stator does not move as a result of this. The stator is in charge of providing the conductor with a magnetic field. It’s usually made of an electromagnet that’s powered by a diesel or other comparable motor. It also has the appearance of a winding coil.

  • The components that transport electrical energy to and from the generator are known as slip rings. They are protected from the shaft by insulation.

  • Brushes connect the slip rings to the outer circuits. They are found on the slip rings’ outer surface.


The rotating of a conductor in a magnetic field is how an AC generator operates. As the conductor spins, the magnetic flux associated with it changes over time due to the changing area. An induced current to flows through the conductor as a result of this. With the use of slip rings, this current is then directed outwards.

Applications of AC Generator

  • An alternating current generator (AC generator) is a type of electric generator that converts mechanical energy into alternating current electrical energy. The operation of an AC generator is governed by the “Electromagnetic Induction” idea.

  • Other applications include outdoor events, lighting flood lights during sporting events, camping, and catering in distant areas.

DC Generator

A DC generator is an electrical machine that converts mechanical energy into electrical energy. When a conductor slices magnetic flux, an emf is created according to Faraday’s Laws’ electromagnetic induction concept. This electromotive force can induce current to flow while the conductor circuit is closed.

DC Generator Diagram

Components of DC Generator

  • The stator’s principal job is to create magnetic fields in which the coil may spin. A stator is made up of two magnets with opposite polarity facing each other. These magnets are positioned throughout the rotor’s circumference.

  • In a DC machine, a rotor is made up of slotted iron laminations that are stacked to form a cylindrical armature core. The goal of the lamination is to minimize the loss caused by eddy current.

  • Armature Windings: Armature windings are connected in series to parallel to increase the sum of produced current in a closed circuit.

  • Yoke is the name given to the DC generator’s exterior construction. It provides the mechanical energy needed to transport the magnetic flux created by the poles.

  • Poles: The field windings are held in place by poles. The armature windings connect these windings in series or parallel, and they are coiled on poles.

  • Pole Shoe: The pole shoe is used to disperse the magnetic flux and keep the field coil from dropping.

  • Within the armature winding, a commutator acts as a rectifier, converting AC electricity to DC voltage. It has a copper section with mica sheets between each copper segment to insulate it from the others. i

  • Brushes: Brushes are used to ensure that the electrical connections between the commutator and the outside load circuit are maintained.


When a current-carrying conductor is put in a fluctuating magnetic field, an emf is induced in the conductor, according to Faraday’s law of electromagnetic induction. The direction of the induced current changes as the direction of motion of the conductor changes, according to Fleming’s right-hand rule. The direction of the conductor’s travel will be reversed downward after the armature completes a half rotation. As a result, the current in each armature will alternate in direction. When a current reversal happens in a split ring commutator, however, the connections of the armature conductors are reversed. As a result, the terminals receive unidirectional current.

Applications of DC Generators

  • DC generators have a number of uses, including:

  • DC generators that are individually stimulated are utilized for power and lighting.

  • Arc lamps, stable current generators, and boosters all employ the series DC generator.

  • To compensate for the voltage loss within Feeders, DC generators are utilized.

  • DC generators are used to power hostels, lodges, offices, and other buildings.


An alternating current generator (AC generator) is an electric generator that converts mechanical energy into electrical energy in the form of alternating current. The “Electromagnetic Induction” concept governs the operation of an AC generator.

During power outages, these generators provide backup power to businesses and homes. Generators do not produce electrical energy; instead, they convert mechanical or chemical energy into it. Generators are divided into two types based on their output: AC generators and DC generators. To learn more about the operating principle, construction, and other aspects of the AC generator, see our article.


Frequently asked questions

Get answers to the most common queries related to the IIT JEE Examination Preparation.

What exactly is the difference between an AC and a DC generator?

Ans: The electrical current in an AC generator alternates its direction on a regular basis, resulting in alternating...Read full

What are the benefits of using alternating current rather than direct current?

Ans: The following are some of the advantages of AC over DC: ...Read full

What is the definition of a commutator?

Ans: It’s a device that connects the armature of a DC generator to the external circuit and helps keep the cur...Read full

What is electromagnetic induction, and how does it work?

Ans: Electromagnetic induction is a phenomenon that occurs when current is created in a circuit by changing the magn...Read full