Difference Between AC and DC Generator

An electrical machine that converts mechanical energy input into electrical energy output is called a generator or electrical generator. There are two types of generators, AC Generators and DC Generator. An AC generator has an electromagnet while a DC generator has a permanent magnet. AC generators have commutators while DC generators have slip rings.

In this article, we will learn what is AC and DC Generators and the Difference Between AC and DC Generator. There are some important differences between AC and DC Generator which we will understand below through the difference table but before that let us understand better what is AC and DC Generator.

What is AC Generator?

A generator that converts mechanical energy into electrical energy in the form of alternating current is called an AC generator. The principle on which an AC generator works is electromagnetic induction.

A machine that converts mechanical energy into electrical energy is called an AC generator or alternator.

The electrical energy generated is in the form of an alternating current sinusoidal output wave. Steam turbines, gas turbines, and combustion engines commonly supply mechanical energy.

Field, armature, prime mover, rotor, stator, and slip ring are the various components of AC generator.

The principle on which an AC generator works is Faraday’s law of electromagnetic induction, which states that an electromotive force EMF or voltage- is produced in a current carrying conductor that intersects a uniform magnetic field in either a Can be obtained by rotating a conducting coil in constant.

AC Generator Working

When the armature rotates between the poles of the magnet on an axis perpendicular to the magnetic field, the flux attaching to the armature is continuously changing.

Due to this emf is induced in the armature. It generates electric current through galvanometer and slip rings and brushes.

The galvanometer oscillates between positive and negative values. This indicates that an alternating current is flowing through the galvanometer.

What is DC Generator?

A machine that converts mechanical energy into DC (direct current) electricity is a DC generator. The DC generator uses the principle of energetically induced electromotive force.

When the conductor reduces the magnetic flux, an EMF will be generated based on the electromagnetic induction principle of Faraday’s laws. The electromotive force produced when a conductor circuit is closed can cause the flow of current.

DC Generator Working

DC generator works on Faraday’s principle of electromagnetic induction which tells us that if an index conductor is rotated in a magnetic flux, then E.M.F (Electromotive force) is generated on that conductor and lasts as long as the conductor continues to rotate.

According to this theory, field, conductor, and motion are all three required to generate voltage. Prime mover is used to rotate the armature.

Prime movers can be diesel engines, water powered machines, wind mills etc. It is run by AC motor.

Difference Between AC and DC Generator

Till now we have learned above what is called Ac and Dc Generator. If you have read all the things given above carefully, then you must have understood well about the difference between AC and DC Generator.

If you still have any confusion in understanding what is AC and DC Generator and what is the difference between them, then now we are going to tell you some important differences between them below.

Parameters	AC Generator	DC Generator
Output Power	It generates AC electrical power.	It produces DC electrical power
Rings	AC generators have close slip-rings.	Dc generators have split-ring commutators.
Current induction	Its output current can be induced in the rotor or stator	Its output current is induced in the rotor only
Direction of Current	The electric current reverses direction from time to time.	Electric current flows in only one direction.
Commutators	AC generators do not have commutators.	DC generators have commutators due to which current flows in only one direction.
Distribution and Transmission	Distribution of output in AC generator is easy.	It is difficult to distribute output in a DC generator.
Efficiency	AC generators are very efficient because energy losses are low.	DC generators are less efficient due to sparking and other losses such as copper, eddy current, mechanical and hysteresis losses.
Maintenance	Requires very less.	Requires very less Requires very less
Types	Rotating armature, Rotating field Single-phase, Three-phase	Permanent magnet, Separately excited, Self-excited
Voltage Distribution	Transformers are used to distribute AC voltage.	Transformers are not used to distribute DC voltage.
Voltage Level	AC generators are useful for generating very high voltages	Dc generator is used to generate low voltage

Difference between AC and DC Generator – FAQs

On What Factors does the Emf Produced in a Generator depend?

The emf produced depends on the number of armature coil turns, the strength of the magnetic field and the speed of the rotating field.

How can you convert an AC Generator to a DC Generator?

To convert an AC generator to DC, add a split ring commutator. This switches current direction, making it behave like a DC generator. Alternatively, replace the coil with an armature for the same effect.

Where are AC and DC Generators Used?

AC generators are used in our household electrical appliances and small motors like vacuum cleaners, juicers and food mixers. Whereas, direct current generators are used in large power electric motors such as those used in subway systems, steam turbines, etc.

Is Battery AC or DC?

Batteries and electronic devices such as televisions, computers and DVD players operate on DC electricity – once AC current enters a device, it is converted to direct current. A typical battery supplies about 1.5 volts direct current.

Which is better AC or DC Generator?

AC generators are more efficient than DC because the energy loss in alternating current is much less. DCs are less efficient due to sparking and other losses in copper, eddy current, mechanical and hysteresis.

What are the Similarities between AC and DC Generator?

The basic similarities between AC and DC Generator is that both works on the principle of electromagnetic induction i.e. when coil is rotated in the presence of magnetic field then electric current is produced.