Unveiling the Types of Electric Generators: How They Work

From the conventional fossil fuel powered generators to the new age renewable energy generators, the dynamic world of electric generators has come a long way. These indispensable devices have been quite helpful in various industries and even in residential and commercial buildings. Still, not everyone knows about these machines in detail. It is what this blog aims to change. Our comprehensive post contains all the information you must have about electric generators. Before delving deep into the specifics, it will introduce you to what an electric generator is in detail.

What is an Electric Generator?

The electric machines that transform mechanical energy into electrical energy are known as electric generators or Dynamos. Now, where does the mechanical energy come from in these generators? Well, mechanical energy in these machines is usually provided by gas turbines, wind turbines and steam turbines. 

Earlier, when the relationship between magnetism and electricity was not discovered, electrostatic generators were used. These generators used electrostatic principles to generate electricity. However, these generators were not used for commercial purposes as they were not able to generate high amounts of electric power. This led to the need for developing electric generators that are capable of generating varying amounts of electric power. 

Components of an Electric Generator

The most significant components of an electric generator are as follows:

• Frame
• Alternator
• Engine
• Voltage Regulator
• Charger
• Exhaust System
• Cooling System
• Lubrication System
• Main Control
• Fuel System

Application of Generator

• Electric generators are widely used to supply power to most of the power networks across different cities. 
• They are used in transportation
• Laboratories have electric generators to fulfill their need for a range of voltage. 
• These are used to drive electric motors.
• Small businesses and households use small-scale electric generators for power backup requirements. 
• Electric generators are used in construction fields for power supply. 

How does a Generator work?

The working principle of the generator mainly involves moving a coil through electromagnetic induction. Generators represent a marvel of engineering, comprising coils of electric conductors, often copper wire, meticulously wound around a metal core. These coils are strategically positioned to rotate within an assembly of powerful magnets. As the electric conductor traverses through the magnetic field, a remarkable phenomenon occurs: magnetism interacts with the electrons within the conductor, catalyzing the generation of electrical current. This transformative process elucidates the fundamental principle underlying generators: the conversion of mechanical energy into electrical power. Through this intricate interplay of magnetic fields and conductors, generators stand as the cornerstone of modern electricity generation, driving innovation and powering the world.

The conductor coil, along with its core, is called an armature. The armature is connected to the mechanical power source. This connection rotates the copper coil at a great speed over the magnetic field. When it first starts to rotate, a weak magnetic field is generated in the iron pole edges. With an increase in its speed, a rise in voltage is observed that builds up the winding current. The increased current production results in enhancing the strength of the magnetic field. The expansion of the magnetic field produces more voltage in the armature, which results in more current. 

How do Electrical Generators Create Energy?

Creating energy is not possible, only its forms are interchanged. Therefore, electrical generators do not generate or create electrical energy. Instead, they transform mechanical or chemical energy into electrical energy. The modern electrical generators work on the principle of Faraday's law of electromagnetic induction. This principle explains that an electromagnetic conductor rotates in the presence of a magnetic field and this rotation creates electrical charges to generate current flow. 

Energy Transformations in Electric Generators

When understanding the workings of an electric generator, it is essential to understand the following energy transformations that take place in it. 

• Mechanical Energy- Generators start with a mechanical energy source. This source can be a steam turbine, water turbine or wind turbine. Hence, the initial form of energy in these machines is the mechanical energy. 
• Kinetic Energy- The initial mechanical energy is converted into kinetic energy with the rotation of the turbine, which provides the mechanical force for driving the generator. 
• Electrical Energy- The kinetic energy is converted into electrical energy through electromagnetic induction. As the armature in the generator rotates due to the magnetic field, induction of electric current is observed in the wire which represents the generation of electrical energy. 
• Electrical Energy Transfer- After electrical energy is generated in the generator the connection points like brushes and slip rings transfer it to the external circuit.
• Useful Energy- Now electrical energy can be used for driving various appliances, providing power to lights, motors and charge batteries.

Types of Generators

Generators are of two types-

AC Generators

Also known as alternators, AC Generators are the most significant machines to produce electrical power where alternating current is used. This generator works on the principle of electromagnetic induction. AC generators can be further classified into two types- Induction generators and Synchronous generators. 

The induction generators use no DC excitation, governor, frequency controls or regulator controls. They work when the conductor coil rotates in the presence of a magnetic field to increase current and voltage. 

Synchronous generators are huge in size. These are usually used in power plants. They can be of rotating armature type or rotating field type. The first one involves the rotation of the armature at the rotor and the field at the stator. The current produced here is transferred through slip rings and brushes. Usually, rotating armature-type generators are used for low-power output applications. On the other hand, rotating field types are used for high power output and they do not contain brushed or slip rings. 

An AC generator can be of two or three-phase generators. A two-phase AC generator produces two separate voltages where each voltage can be considered as single-phase voltage as they both are generated completely independent of each other. The AC generators are packaged with a turbine or an engine that is used as a motor generator set for gas and oil extraction, wind power plants, mining machinery and naval. 

DC Generators

Another type of generator is the DC generators, that are usually found in off-grid applications. These generators offer a seamless power supply to electric storage devices. They store power that is carried to the load by AC-DC converters. These generators are classified into- permanent-magnet DC generators, separately-excited DC generators and self-excited DC generators.

The permanent magnet DC generators are used for low-power applications. They do not need an external field excitation as they have permanent magnets for flux production. On the other hand, separately excited DC generators need an external field excitation for flux production. These generators are commonly used for electrorefining and electroplating purposes. Self-excited DC generators have magnetism present in the poles of their stator. Therefore, they produce their magnetic field after they start. They are simple to use and are commonly used for welding, battery charging, and ordinary lighting. 

Inverter vs Generator 

A generator doesn't store electricity but rather creates it when power is supplied to it. Naturally, there exists a temporal gap between its activation and the restoration of power in the event of a utility supply failure. Understanding this inherent characteristic of generators is vital for effectively managing power outages and ensuring seamless transitions to backup power sources. 

On the other hand, a power inverter setup serves as a vital component for storing energy in batteries, utilizing direct current (DC) for this purpose. In its operation, it efficiently transforms alternating current (AC) from the mains into DC during the charging phase, seamlessly storing this energy. Subsequently, it swiftly converts the stored DC back into AC to power your appliances without any noticeable delay or manual intervention required. 

Read Also - YOU SHOULD KNOW WHAT YOU NEED: A UPS OR INVERTER

Bottom Line

Generators are an important innovation. However, it is essential to understand their work and types to decide the best one for a particular purpose. Our blog above must have helped you with this information. Also, if you are looking for an electric generator, you can shop from Schneider Electric's online store- https://eshop.se.com/in/. We offer easy deliveries and installation to make the entire purchase journey convenient. 

Frequently Asked Questions

Q1. What is an Electric Generator?

Ans: An electric generator is a machine that converts mechanical energy into electrical energy for supplying power to various machines and appliances.

Q2. What are the applications of Electric Generators?

Ans: Electric generators are used in various places like for transportation. These machines are installed on construction fields before the power supply is set up. 

Q3. Do Electric Generators generate electricity?

Ans:  No, electricity is not generated by electric generators. Electrical energy is formed in these machines by converting mechanical energy into electrical energy.