What is the main function of a transformer?

The primary function of a transformer is to change AC voltage levels. Transformers work on the principle of electromagnetic induction, allowing them to either increase (step-up) or decrease (step-down) the voltage of alternating current while keeping the frequency constant. This capability is crucial in power distribution systems, where electrical power generated at high voltages needs to be transmitted over long distances efficiently and then reduced to lower voltages suitable for commercial or residential use.

Transformers achieve this by using two or more coils of wire (windings) that are magnetically linked. When AC voltage is applied to one winding (the primary winding), it creates a magnetic field that induces a voltage in the other winding (the secondary winding). The ratio of the number of turns in the primary to the secondary winding determines the voltage change. This function is essential in ensuring safe and efficient distribution of electrical power, making transformers integral to the electrical grid.