I always have Exaggerated and aversive claims of impending scientific and technical breakthroughs, such as inexpensive merger, supersonic travel, and rehabilitating other planets. But I’m fond of simple devices that do a lot of the basic work of modern civilization, especially those that do so modestly – or even invisibly.
There is no better device than this description than an adapter. Non-engineers may be vaguely aware that such devices exist, but they have no idea how they work and how they are completely indispensable for everyday life. (A transformer is a device that transfers electricity between two circuits during a voltage change, that is, to “compress” the power of an electric current.)
The theoretical basis was laid in the early 1830s, with the independent discovery of electromagnetic induction by Michael Faraday and Joseph Henry. They showed that a changing magnetic field can induce a current of a higher voltage (known as a “step up”) or a lower current (a “step down”). But it took another half a century before Lucien Gollard, John Dickson Gibbs, Charles Burch, and Sebastian Ziani de Ferrante could design the first useful prototypes of the transformers. Then, three Hungarian engineers – Otto Plati, Mixa Dere, and Karoly Zbernowski – improved the design by constructing a toroidal transformer (shaped like a donut), which they demonstrated in 1885.
The following year, a better design was presented by three American engineers – William Stanley, Albert Schmid, and Oliver B. Schallenberger, who were working for George Westinghouse. The device quickly took the classic Stanley transformer shape that has been kept ever since: a central iron core made of thin silicon steel sheets, one part “E” and the other “I” shaped to make it easier to insert the copper coils in place.
In his speech to the American Institute of Electrical Engineers in 1912, Stanley rightly marveled at the way the device presented “such a complete and simple solution to a difficult problem. He thus ashamed all mechanical attempts to regulate. He deals with such ease and certainty and economy with the enormous amounts of energy that It is given or taken from it instantly. It is extremely reliable, strong and assured. In this copper alloyed metal, the extraordinary forces are so well balanced that they are almost unpredictable. “
The most recent incarnation of this durable design has made it possible to conduct electricity over great distances. In 2018, Siemens delivered the first of seven standard 1100 kV transformers, which will enable many Chinese provinces to supply electricity associated with a 3300 km high voltage DC line.
The sheer number of adapters has risen above anything Stanley could have imagined, thanks to the explosion of portable electronic devices that must be charged. In 2016, global smartphone production alone exceeded 1.8 billion units, each powered by a charger containing a miniature adapter. You don’t have to disconnect your phone charger to see the core of this little device; A complete disassembly of the iPhone charger is published online, with the adapter being one of its biggest components.
But many chargers have smaller adapters. These devices are not by Stanley (i.e. not wrapped with wire) that take advantage of the piezoelectric effect – the strained ability of the crystal to produce current, and the ability of the current to stress or distort the crystal. Sound waves hitting such a crystal can produce a current, and the current flowing through this crystal can produce a sound. One current can be used in this way to generate another current at completely different voltages.
And the latest innovation is electronic transformers. Their size and mass are greatly reduced compared to conventional units, and will become of particular interest for integrating intermittent sources of electricity – wind and solar energy – into the grid and enabling small DC networks. Without transformers, we wouldn’t have an age of electricity everywhere, and we’d be stuck in an era of oil lamps and the telegraph.
from The numbers don’t lie Written by Vaclav Smil, published by Penguin Books, an imprint of the Penguin Publishing Group, a division of Penguin Random House, LLC. Copyright © 2020 by Vaclav Smil.
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