Electric generators are very common mechanical devices. There are mainly two electric generators: AC and DC generators. The primary role of a DC generator is to supply electricity by converting mechanical energy into an electric one. DC generators are constructed by following Faraday’s law of electromagnetic induction. They have applications in heavy industries and machinery. The following article explains the working and advantages and disadvantages of DC generators.

Electric Generators

Electric generators are devices used to convert mechanical energy into electrical energy. These generators are used to supply power to various machines and appliances. Electric generators have various applications in industries and factories to operate heavy machines. Small generators can also be used for supplying electricity to regular appliances. 

Principle

The electric generator works on the principle of Faraday’s law, which states that a conductor will experience an electric current once placed in an unstable environment of a strong magnetic field. Both AC and DC generators are constructed following Faraday’s law.

Applications of an Electric Generator

The applications of electric generators are mentioned below:

  • Electric generators are used where a power supply is needed, such as in industries, areas with a power outage, and others
  • They are majorly used as a backup to power shortages
  • They are actively used in remote areas, construction sites, and heavy industrial machines

There are two types of electric generators:

  • AC Generators
  • DC Generators

Let us now understand how a DC generator works.

DC Generators

A DC generator or direct current generator is a type of electric generator; its primary function is to convert a mechanical input into a direct current electricity output. There are many advantages of DC generators.

The Working Principle

A DC generator works based on Faraday’s law of electromagnetic induction. When a conductor is placed in a system of unstable or rapidly changing magnetic fields, an electromotive force is generated in the conductor; this electromagnetic force causes an electric current to flow in the system. 

Making a DC Generator

A general DC conductor consists of the followings:

  1. A rectangular coil (ABCD)
  2. A powerful magnet (horseshoe magnet); if two magnets are being used, it is essential to face opposite sides of the magnets to each other.
  3. The coil (ABCD) is placed perpendicular to the magnet.
  4. The ends of the rectangular coil (ABCD) are connected to a commutator (in this case, a split ring, let us say P and Q).
  5. Two stationary brushes, X and Y, are connected with these commutators (P, Q).
  6. The inner sides of the commutators are then connected with a spindle.
  7. The spindle is mechanically rotated to rotate the coil (ABCD).
  8. The brushes X and Y are connected with a mechanical Galvanometer to record current flow through the DC generator.

Advantages of DC Generators

Let us understand the importance of DC generators.

  • The design and construction of a DC generator are simple
  • They are used to operate big machines
  • These generators are useful in supplying electricity to large motors
  • Heavy electric devices are supplied electricity by using DC generators
  • A DC generator significantly reduces the electric fluctuations in the armature and gives a continuous supply

Disadvantages of DC Generators

DC generators have several disadvantages: 

  • A major disadvantage of a DC generator is that it can not be used with a transformer
  • The efficiency of a DC generator is very low
  • The current flowing in the generator experiences various losses such as Eddy current losses, copper losses, mechanical losses, and others
  • DC generators placed at a long distance may experience major voltage drops

Conclusion

A DC generator is a mechanical device that converts a mechanical input into an electric output, and this device is used to generate electricity. The DC generator has multiple applications in general usage, supply appliances, and operating heavy machines in factories. The DC generator follows Faraday’s law as its working principle. There are many advantages of DC generators; for instance, these machines have less fluctuations in their outputs and are suitable for big machines. However, DC generators have some disadvantages: they can not be used with a transformer and may experience voltage drops.