ELECTRIC GENERATORS
Electric Generators: How Do They Work?
Electric generators are devices that transform mechanical energy obtained from an external source into electrical energy.
It is important to understand that electric generators do not "create" electrical energy, but they do use mechanical energy, which produces force through the movement of electrical loads that are in an external electrical circuit.
At the moment, electric generators work on the principle of electromagnetic induction discovered by Michael Faraday in 1831-32. Faraday found out that above flux of electrical loads could be induced by moving an electrical conductor, as well as a wire with electrical loads in it. located in a magnetic field. This movement creates a difference of voltage between the two ends of the wire or the electrical conductor which in turn causes the flux of electrical loads to generate electric current.
Electric generators, main components:
- Engine
- Alternator
- Fuel system
- Voltage regulator
- Cooling and exhaust system
- Lubrication system
- Battery charger
- Control panel
Description of the main components of electric generators:
- Engine:
The engine is the source of mechanical energy. The size of the engine is proportional to the maximum power of the electric generator. There are several factors that have to be taken into account when the engine is evaluated. To know exactly how the engine and the maintenance programmes operate, ask the manufacturer.
Electric generators operate on various types of fuel. For instance, diesel, gasoline, propane (liquid or gaseous) or natural gas. The smallest engines are often powered by gasoline, whereas the biggest ones are usually powered by diesel, propane (liquid or gaseous) or natural gas. Some engines can also be powered by a double diesel/gas fuel system so-called bi-fuel.
Overhead valve (OHV) engines vary from the other, because engine intake and exhaust valves are mounted in the top part of the cylinder instead of in the engine cylinder block.
Unlike other types of engines, OHV engines have a wide range of advantages, such as:
- Compact design
- Simple mechanism operation
- Durability
- Easy to use
- Low noise level
- Ecologically friendly
However, OHV engines are more expensive than other types of engines.
Cast iron sleeve (CIS) in engine cylinder is not an expensive component, but it plays an important role in the durability of the engine, specially if the electric generator is needed very frequently or during prolonged periods of time.
- Alternator
- Stator: It is a stanby component and contains a set of electrical conductors.
- Rotor: It is a moving part and produces a magnetic field in any of the following ways:
- Induction
- Through standby magnets
- Through a small source of continuous current
- Fuel system
It transforms electrical power into mechanical energy supplied by the engine. It contains a set of standby and portable parts in an on-board box. Components work together in order to cause the movement of the magnetic and electrical fields, which in turn generate electricity.
Generally, the fuel tank has space enough to keep the generator operating during 6-8 hours.
