Transformers range significantly in size with minuscule transformers of volume less than a cubic centimetre used with some basic circuits, whilst the largest transformers can weigh hundreds of tonnes and support a full national power grid to supply electricity to a country. The cores inside of the transformers can be constructed of various materials to affect how the electrical current will pass through the device; these include:
Silicon steel cores
Powered iron cores
Metal alloy cores.
Dependent on the application of the circuit for which a transformer is being used in conjunction with, a transformer may be wound in a number of ways to ensure that it is best suited to fulfil its requirements. This can include things such as a stranded conductor (the winding of wire) to make it more flexible and easier to manufacture, splitting the structure into sections of coils to minimise the leakage during the induction of the electrical energy or including taps within the transformer for voltage adjustment.
To raise or lower the level of voltage or current
To prevent direct current (DC) from passing from one circuit to another
Isolate circuits electrically
To distribute electrical energy throughout a power supply network such as a commercial or industrial area
Power collection (e.g. wind farm)
Used in small appliances and circuits to prevent short-circuiting