We rely on generators to power up our appliances, tools, computers, lights, and more, when we need power the most – but how does it work? Here, we take a look at what really happens inside a generator.
Simply put, a generator is an electric generator is a device that converts mechanical energy to electrical energy. Generators are built on the phenomena of electromagnetism.
This mans a generator does not actually ‘create’ energy. Instead, it uses the mechanical energy supplied to it to force the movement of electric charges present in the wire of its windings through an external electric circuit. This flow of electric charges provides the output electric current supplied by the generator. Think of it like a water pump; a water pump causes the flow of water but does not actually ‘create’ the water flowing through it.
The generator is built on the principle of electromagnetic induction discovered by Michael Faraday the 1830s, and aptly named “Faraday’s law”. Faraday discovered that moving an electrical conductor, like a wire containing electric charges, in a magnetic field could induce the flow of electric charges. This movement creates a voltage difference between the two ends of the wire or electrical conductor, which in turn causes the electric charges to flow, thus generating electric current.
Modern day generators comprise many components housed in a frame or casing, including an engine, alternator, fuel system, voltage regulator, cooling and exhaust systems, lubrication system, battery charger, and control panel.
The engine provides the mechanical energy to the generator. It follows, then, that the size of the engine is directly proportional to the maximum power output the generator can supply. The alternator produces the electrical output from the mechanical input supplied by the engine. It contains an assembly of stationary and moving parts encased in a housing, such as brushes and sliprings. The components work together to cause relative movement between the magnetic and electric fields, which in turn generates electricity.
The generator’s voltage output is regulated by a voltage regulator. When you add a load – an appliance – to a generator, its output voltage dips a little. This prompts the voltage regulator into action. The regulator takes a very small portion of the generators output, and converts that AC voltage into a DC current that is inversely proportional to the generator’s output voltage (once it reaches full voltage). In other words, the more voltage output of the generator, the less DC current the voltage regulator produces.
Depending on how you will use your generator and the power required, there are different types and sizes to meet your needs. Read our generator buyer's guide here to find out more.