Who Invented the Transformer?

The transformer is one of the key inventions fundamental to creating the electrified world. The very concept of AC electricity does not work without them, so in a world without transformers, many of our common devices would not be recognizable. However, this is one of those devices that was not really invented by any single person. Instead, many scientists and inventors contributed pieces to the puzzle.

Identification

A transformer is a device for changing the voltage of electricity. In popular use, it refers to the type of transformer that steps high voltage electricity down to the level necessary for domestic use. If you have electrical feed wires on telephone poles in your neighborhood, look around. In America, transformers often appear as large cylinders perched atop a telephone pole, with three or four feed cables running into nearby houses. All voltage converters used by travelers are also transformers.

Function

A transformer changes voltage by means of mutual electromagnetic induction. The electrical current running through the primary coil/circuit is used to create a magnetic field. Changes in the current result in changes in the magnetic field, which in turn alters the voltage of the secondary coil/circuit.

History

The science behind transformers was demonstrated in principle by Michael Faraday in 1831. The first widely used transformer-type device, however, had nothing to do with AC power. It was instead the induction coil, invented by Irishman Nicholas Callan in 1836. Callan was looking for a way of making batteries more efficient, and while this was done using DC technology, it was an important contribution to the future.
The next step was the lighting system developed by Russian Pavel Yoblochkov in 1876, using induction coils and AC power to run several "electric candles."
Having acquired a transformer device design from a Frenchman, Lucien Gaulard, in the middle 1880s, the Westinghouse Company began experimenting with it. Westinghouse engineer William Stanley developed the first commercial transformer by 1886. Improvements to this design were made by Mikhail Dolivo-Dobrovolsky and the famed genius Nikola Tesla. Tesla's contribution, the Tesla Coil, made possible the transmission of very high voltage electricity at a high frequency, thus opening the way for the modern system of electric distribution we have today.

Types

Four common uses for transformers exist today. Two are to step up voltage for high voltage power transmission and then step it down for distribution and consumption. This is done between power plants and consumers.
A third is in the voltage converter available for people traveling between North America and other continents. North American electricity is distributed for consumption at 110 volts, while internationally it is more common to see it used at 220 volts. Thus, American computers and other appliances that are taken abroad need transformers to be safely used.
Finally, transformers are found in every AC adapter.

Considerations

One of the amazing things about transformers is that they are extremely energy efficient. Most designs suffer very little power loss in changing voltages. The least efficient designs are actually those found in the common power adapters, such as the one attached to laptop computers. However, even these transformers are more than twice as energy efficient as an internal combustion engine, for example.