https://en.wikipedia.org/wiki/Mikhail_Dolivo-Dobrovolsky
As one of the founders (the others were Nikola Tesla, Galileo Ferraris and Jonas Wenström) of polyphase electrical systems, he developed the three-phase electrical generator and a three-phase electrical motor (1888) and studied star and delta connections. The triumph of the three-phase system was displayed in Europe at the International Electro-Technical Exhibition of 1891, where Dolivo-Dobrovolsky used this system to transmit electric power at the distance of 176 km with 75% efficiency. In 1891 he also created a three-phase transformer and short-circuited (squirrel-cage) induction motor.[1][2] He designed the world's first three-phase hydroelectric power plant in 1891.