How a Transformer Works

Explanation by engineer, power transmission pioneer Lionel Barthold. Basic description with diagrams showing the behavior of electric power in a transformer.
A transformer transfers power between two or more separate circuits using induction. The Electromagnetic Field (EMF) transforms power across a medium from one wire to another. The ratio of windings in the primary vs the secondary winding will determine the change in voltage in an AC system. Induction was discovered in Michael Faraday and Joseph Henry in the 1820s. The Ganz Company in Budapest was the first to use transformers in a complete AC power system (1870s). "Transformers are the heart of the alternating current system" - William Stanley (1886) Transformers, generators, and transmission wires are the three most basic components of any utility power system.