Galileo Ferraris (31 October 1847 – 7 February 1897) was an Italian university professor,
physicist
A physicist is a scientist who specializes in the field of physics, which encompasses the interactions of matter and energy at all length and time scales in the physical universe. Physicists generally are interested in the root or ultimate cau ...
and
electrical engineer
Electrical engineering is an engineering discipline concerned with the study, design, and application of equipment, devices, and systems that use electricity, electronics, and electromagnetism. It emerged as an identifiable occupation in the l ...
, one of the pioneers of
AC power
In an electric circuit, instantaneous power is the time rate of flow of energy past a given point of the circuit. In alternating current circuits, energy storage elements such as inductors and capacitors may result in periodic reversals of the d ...
system and inventor of the
induction motor
An induction motor or asynchronous motor is an AC motor, AC electric motor in which the electric current in the rotor (electric), rotor that produces torque is obtained by electromagnetic induction from the magnetic field of the stator winding ...
although he never patented his work. Many newspapers touted that his work on the induction motor and power transmission systems were some of the greatest inventions of all ages. 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
Lucien Gaulard (16 July 1850 – 26 November 1888) was a French engineer who invented devices for the transmission of alternating current electrical energy.
Biography
Gaulard was born in Paris, France in 1850.
A power transformer developed by G ...
and
John Dixon Gibbs.
Biography

Born at
Livorno Vercellese
Livorno Ferraris is a ''comune'' (municipality) in the Province of Vercelli in the Italy, Italian region of Piedmont, located about northeast of Turin and about west of Vercelli.
Originally known as Livorno Vercellese or Livorno Piemonte, later ...
(
Kingdom of Sardinia
The Kingdom of Sardinia, also referred to as the Kingdom of Sardinia and Corsica among other names, was a State (polity), country in Southern Europe from the late 13th until the mid-19th century, and from 1297 to 1768 for the Corsican part of ...
), 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
An alternator (or synchronous generator) is an electrical generator that converts mechanical energy to electrical energy in the form of alternating current. For reasons of cost and simplicity, most alternators use a rotating magnetic field wit ...
, 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
Turin ( , ; ; , then ) is a city and an important business and cultural centre in northern Italy. It is the capital city of Piedmont and of the Metropolitan City of Turin, and was the first Italian capital from 1861 to 1865. The city is main ...
(two months later
Nikola Tesla
Nikola Tesla (;["Tesla"](_blank)
. ''Random House Webster's Unabridged Dictionary''. ; 10 July 1856 – 7 ...
gained , an application filed 12 October 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 a 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
In electrical engineering, a transformer is a passive component that transfers electrical energy from one electrical circuit to another circuit, or multiple Electrical network, circuits. A varying current in any coil of the transformer produces ...
. 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
An electric motor is a machine that converts electrical energy into mechanical energy. Most electric motors operate through the interaction between the motor's magnetic field and electric current in a electromagnetic coil, wire winding to gene ...
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.
In 1889, Ferraris worked at the Italian Industrial Institution, a school of electrical engineering (the first school of this kind in Italy, subsequently incorporated in the
Politecnico di Torino
The Polytechnic University of Turin (, abbreviated as PoliTO) is the oldest Italian public technical university. The university offers several courses in the fields of Engineering, Architecture, Urban Planning and Industrial Design, and is consi ...
). In 1896, Ferraris joined the
Italian Electrotechnical Association and became the first national president of the organization.
Galileo Ferraris did not confine his research interests to electricity. He also researched the fundamental properties of
dioptric instruments and made an elementary representation of the theory and its applications. His work contains a detailed description of the geometric dioptrics for uncentered systems. He provided a greater generality as previously found in the telescopic system treatments, with less emphasis on applications.
In the second main section, the results obtained are applied to optical instruments. The magnification, field of view, and the brightness of the instrument were dealt with in great detail. The field denned as the author of the cone opening angle, the tip of the first main points of the lens, and its base formed by the parts of the object in view, will possess the same brightness. The eye is not treated.
Memorials
A
Ferraris disk motor is named after its inventor.
The city of
Turin
Turin ( , ; ; , then ) is a city and an important business and cultural centre in northern Italy. It is the capital city of Piedmont and of the Metropolitan City of Turin, and was the first Italian capital from 1861 to 1865. The city is main ...
honoured the contributions that Ferraris made to science.
A general committee proposed an addition to the Royal Industrial Museum of Turin with a permanent monument commemorating his scientific and industrial achievements.
Additionally, an avenue was named in honour of Ferraris.
In January 2021 Ferraris was honoured by the
IEEE
The Institute of Electrical and Electronics Engineers (IEEE) is an American 501(c)(3) organization, 501(c)(3) public charity professional organization for electrical engineering, electronics engineering, and other related disciplines.
The IEEE ...
Milestones program for his contribution to "the technological innovation and excellence for the benefit of humanity", namely for his “Rotating Fields and Early Induction Motors, 1885-1888�
The according plaque carries the inscription:
''Galileo Ferraris, professor at the Italian Industrial Museum (now Polytechnic) of Turin, conceived and demonstrated the principle of the rotating magnetic field. Ferraris’ field, produced by two stationary coils with perpendicular axes, was driven by alternating currents phase-shifted by 90 degrees. Ferraris also constructed prototypes of two-phase AC motors. Rotating fields, polyphase currents, and their application to induction motors had a fundamental role in the electrification of the world.''
Publications
*
*
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Sulle differenze di fase delle correnti e sulla dissipazione di energia nei trasformatori by Prof. Galileo Ferraris (Turin, 1887).
*
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** Online texts
vol. 1vol. 2vol. 3
References
Further reading
External links
* B. Bowers
"Scanning our past from London: Galileo Ferraris and alternating current"in Proceedings of the IEEE, vol. 89, no. 5, pp. 790–792, May 2001, doi: 10.1109/5.929656.
*M. Mitolo and M. Tartaglia
"Galileo Farraris - A Life Dedicated to the Electric Sciences [History">istory">
"Galileo Farraris - A Life Dedicated to the Electric Sciences [History
in IEEE Industry Applications Magazine, vol. 22, no. 5, pp. 8–11, Sept.-Oct. 2016, doi: 10.1109/MIAS.2016.2574223.
*Raffaella Gobbo, ''L'archivio di Galileo Ferraris'', Roma, Amministrazione degli Archivi di Stato, 2005. Estratto da: ''Rassegna degli Archivi di Stato'', n. s., 1 (2005), n. 1-2, 9–169 p. Chronology of Galileo Ferarris, 24-33 p.
*
Museo Ferraris'
*
Opere di Galileo Ferraris Vol. 1.'
*
Opere di Galileo Ferraris Vol. 2.'
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* ''
ttp://ieeemilestones.ethw.org/images/0/0c/Tartaglia.pdf M. Mitolo, M.Tartaglia, Galileo Ferraris: A Life Dedicated to the Electrical Sciences, IEEE Industry Appl. Magazine, 2016, pp 8-11 ''
*
Power Electric Circuits: Pacinotti and Ferraris The pioneering age of power circuits, pp. 51-58 in A Short History of Circuits and Systems''
*
Silvanus Phillips Thompson: Polyphase electric currents and alternate current motors'
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Univ.Prof. Dr.Ing. Martin Doppelbauer: The invention of the electric motor, Karlsruhe Institute of Technology - KIT '
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Brian Bowers, Galileo Ferraris and Alternating Current, IEEE Proc, vol. 89, n.5, May 2001, pp. 790-792''
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Galileo Ferraris, Rotazioni elettrodinamiche prodotte per mezzo di correnti alternate (Electrodynamic rotations by means of alternating currents), memory read at Accademia delle Scienze, Torino, March 1888 in Opere di Galileo Ferraris, Hoepli, Milano, 1902 vol I pp 333-348 ''
*
WilliamStanley: Alternating-current development in America'
* Katz, Eugenii, "
'". Biosensors & Bioelectronics.
*
Istituto Elettrotecnico Nazionale Galileo Ferraris' (IEN) – Official web site (English)
Alternating Current Development in America by William StanleyGalileo Ferraris, Britannica
{{DEFAULTSORT:Ferraris, Galileo
1847 births
1897 deaths
Italian electrical engineers
19th-century Italian physicists
19th-century Italian inventors
People from the Province of Vercelli
19th-century Italian engineers