What is the primary function of a transformer?

The primary function of a transformer is to change the voltage level of electricity. Transformers operate on the principle of electromagnetic induction to either step up (increase) or step down (decrease) voltage levels in an electrical system. This voltage adjustment is crucial for efficient power distribution and transmission, as it allows electricity to travel long distances with minimal loss. For instance, high voltages are typically used for long-distance transmission to reduce energy losses, and transformers can then step down the voltage to safer, usable levels for consumers.

While there are other devices that can convert DC to AC, store electrical energy, or isolate circuits, those functions do not relate to the core purpose of transformers. Transforming voltage is the key role of a transformer within electrical systems.