Galileo Ferraris

Galileo Ferraris
Galileo Ferraris
Born	31 October 1847 Livorno Vercellese, Kingdom of Sardinia
Died	7 February 1897 (1897-02-08) (aged 49) Turin, Kingdom of Italy
Nationality	Italian
Fields	physics, engineering
Known for	Alternating current

Galileo Ferraris (31 October 1847 – 7 February 1897) was an Italian physicist and electrical engineer, one of the pioneers of AC power system and the inventor of induction motor. Many newspapers published that Ferraris's work on the induction motor and power transmission systems was one of the greatest inventions of any age. He published an extensive and complete monograph on the experimental results obtained with open-circuit transformers of the type designed by the power engineers Lucien Gaulard and John Dixon Gibbs.

Born at Livorno Vercellese (Kingdom of Sardinia), Ferraris gained a master's degree in engineering and became an assistant of technical physics near the Regal Italian Industrial Museum. Ferraris independently researched the rotary magnetic field in 1885. Ferraris experimented with different types of asynchronous electric motors. The research and his studies resulted in the development of an alternator, which may be thought of as an alternating-current motor operating in reverse, so as to convert mechanical (rotating) power into electric power (as alternating current).

On 11 March 1888, Ferraris published his research in a paper to the Royal Academy of Sciences in Turin (two months later Nikola Tesla gained U.S. Patent 381,968, application filed October 12, 1887. Serial Number 252,132). These alternators operated by creating systems of alternating currents displaced from one another in phase by definite amounts, and depended on rotating magnetic field for their operation. The resulting source of polyphase power soon found widespread acceptance. The invention of the polyphase alternator is key in the history of electrification, as is the power transformer. These inventions enabled power to be transmitted by wires economically over considerable distances. Polyphase power enabled the use of water-power (via hydroelectric generating plants in large dams) in remote places, thereby allowing the mechanical energy of the falling water to be converted to electricity, which then could be fed to an electric motor at any location where mechanical work needed to be done. This versatility sparked the growth of power-transmission network grids on continents around the globe.