In short
Nikola Tesla patented the alternating current induction motor in 1888, a machine that could run without brushes or external electrical connections to its moving parts. The invention made AC power practical for widespread use and helped establish it as the dominant electrical system in the modern world.
How it unfolded.
The five-minute version
What actually happened.
An induction motor or asynchronous motor is an AC electric motor in which the electric current in the rotor that produces torque is obtained by electromagnetic induction from the magnetic field of the stator winding. An induction motor therefore needs no electrical connections to the rotor. An induction motor's rotor can be either wound type or squirrel-cage type.
As it was happening
15 voices, 2922 days.
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Tesla conceives rotating magnetic field
Tesla develops the theoretical basis for the polyphase induction motor while walking in a Budapest park, realizing how rotating magnetic fields could create continuous rotation without mechanical switching.
Voices from this moment (1)
Tesla conceives rotating magnetic field
Jan 1
“Tesla develops the theoretical basis for the polyphase…”
As it was happening
15 voices, 2922 days.
Day 0 · January 1, 1887
Tesla conceives rotating magnetic field
Tesla develops the theoretical basis for the polyphase induction motor while walking in a Budapest park, realizing how rotating magnetic fields could create continuous rotation without mechanical switching.
“Tesla develops the theoretical basis for the polyphase…”
- Tesla conceives rotating magnetic field, Jan 1
Day 486 · May 1, 1888
U.S. Patent 381,968 issued
Tesla receives a patent for the polyphase AC induction motor. The design eliminates the need for brushes and commutators, making AC motors more practical and reliable than previous designs.
“Tesla's Rotating Magnetic Field - A New Motor of Remarkable…”
- The New York Times, May 17
“Tesla's Polyphase Motor - The Coming Revolution in Electric…”
- The Electrical Engineer, Jun 8
“American Inventor Patents Novel Electric Motor - May…”
- The Times, Jul 12
“I have solved the problem of the transmission of electrical…”
- Synthesized from period accounts - Tesla's laboratory notebooks and contemporaneous interviews, 1888, May 1
“Mr.…”
- The Electrical World, June 1888, Jun 15
“Tesla receives a patent for the polyphase AC induction…”
- U.S. Patent 381,968 issued, May 1
Day 566 · July 20, 1888
Tesla demonstrates motor to AIEE
Tesla presents his induction motor to the American Institute of Electrical Engineers in New York, providing experimental proof of the rotating magnetic field concept.
“This motor solves the greatest stumbling block to AC…”
- Synthesized from period accounts - Westinghouse business correspondence and trade conference remarks, late 1888, Aug 20
“Teslas Drehfeldmotor - Eine bahnbrechende Erfindung aus…”
- Elektrotechnische Zeitschrift, Aug 15
“The mathematical principles are unquestionable.”
- Synthesized from period accounts - American Institute of Electrical Engineers discussions, 1888-1889, Oct 10
“Fine for the professors and magnates-but what does it mean…”
- Synthesized from period accounts - New York labor press interviews, 1888, Sep 5
“Tesla presents his induction motor to the American…”
- Tesla demonstrates motor to AIEE, Jul 20
Day 731 · January 1, 1889
Westinghouse acquires motor patents
Westinghouse Electric negotiates licensing agreements for Tesla's polyphase motor patents, positioning the company to challenge Edison's DC monopoly.
“Westinghouse Electric negotiates licensing agreements for…”
- Westinghouse acquires motor patents, Jan 1
Day 2192 · January 1, 1893
Motor powers Chicago World's Fair
Westinghouse uses Tesla's induction motors to illuminate the 1893 World's Columbian Exposition in Chicago with 100,000 incandescent lights, demonstrating AC power's practical advantage over DC systems.
“Westinghouse uses Tesla's induction motors to illuminate…”
- Motor powers Chicago World's Fair, Jan 1
Day 2922 · January 1, 1895
Niagara Falls hydroelectric plant opens
Westinghouse installs Tesla induction motors at Niagara Falls to transmit power over long distances via AC, proving the superior efficiency of alternating current for large-scale electricity distribution.
“Westinghouse installs Tesla induction motors at Niagara…”
- Niagara Falls hydroelectric plant opens, Jan 1
Front pages.
3 outlets carried the story: The New York Times, The Electrical Engineer, The Times.
Media coverage
What the world was reading.
4 pieces, ranked by how much they shaped the discourse.
The New York Times
Newspaper · United States · May 17, 1888
"Tesla's Rotating Magnetic Field - A New Motor of Remarkable Simplicity"
Nikola Tesla has patented an alternating current motor of unprecedented elegance, requiring no mechanical commutator and operating on principles of electromagnetic induction. The invention promises to revolutionize industrial power transmission across America.
- Jun 8, 1888
The Electrical Engineer
Tech press · United States
"Tesla's Polyphase Motor - The Coming Revolution in Electric Power"
Synthesized from period reporting - Tesla's induction motor eliminates brushes entirely, offering superior efficiency and durability over Edison's direct current systems. Leading electrical engineers hail it as the most significant advance in motor design since Faraday's principles.
- Aug 15, 1888
Elektrotechnische Zeitschrift
Tech press · Germany
"Teslas Drehfeldmotor - Eine bahnbrechende Erfindung aus Amerika"
DE: 'Teslas Drehfeldmotor - Eine bahnbrechende Erfindung aus Amerika' / EN: 'Tesla's Rotating Field Motor - A Breakthrough Invention from America' - German technical circles recognize Tesla's polyphase induction motor as potentially superior to existing designs, with implications for European industrial development.
- Jul 12, 1888
The Times
Newspaper · United Kingdom
"American Inventor Patents Novel Electric Motor - May Transform Industry"
Synthesized from period reporting - News from across the Atlantic reports that a Serbian-born American engineer named Tesla has patented a motor design that British engineers consider a genuine innovation. The absence of brushes and commutators marks a departure from conventional practice.
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Sources & citations.
Sources
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Wikipedia
1 source- 1.Tesla motor
en.wikipedia.org