On December 13, 1892. Nikola Tesla patented system of electrical transmission of power.
Critical Features: Alternating current generator consisting of independent armature-circuits formed by conductors alternately disposed; Currents developed differ in phase and the field magnet poles in excess of the number of armature-circuits; Multipolar alternating-current machine.
Publication number: US487796 A
Patent Title: Nikola tesla
Publication type: Grant
Publication date: 13 Dec 1892
Filing date: 15 May 1888
Inventors: Nikola Tesla
Original Assignee: The Tesla Electric company