AC and the induction motor

In late 1886 Tesla met Alfred S. Brown, a Western Union superintendent, and New York attorney Charles F. Peck. The two men were experienced in setting up companies and promoting inventions and patents for financial gain. Based on Tesla's patents and other ideas they agreed to back him financially and handle his patents. Together in April 1887 they formed the Tesla Electric Company with an agreement that profits from generated patents would go 1/3 to Tesla, 1/3 to Peck and Brown, and 1/3 to fund development. They set up a laboratory for Tesla at 89 Liberty Street in Manhattan where he worked on improving and developing new types of electric motors, generators and other devices.

One of the things Tesla developed at that laboratory in 1887 was an induction motor that ran on alternating current, a power system format that was starting to be built in Europe and the US because of its advantages in long distance high voltage transmission. The motor used polyphase current which generated a rotating magnetic field to turn the motor (a principle Tesla claimed to have conceived of in 1882). This innovative electric motor, patented in May 1888, was a simple self-starting design that did not need a commutator, thus avoiding sparking and the high maintenance of constantly servicing and replacing mechanical brushes.:161