In order to solve a series of technical problems in electrical applications, such as transmission, DC to AC, high voltage to low voltage, etc. A group of engineers from Westinghouse Electric Company played an important role. For example, William Stanley improved the transformer, Auliffe Shallenberger invented the AC induction meter, Nikola Trass invented the induction motor (1889) and obtained many patents for the motor, L·B· Stilwell made the voltage regulator, Benjamin Lamben improved the squirrel-cage induction motor and the first practical tram motor, and changed the AC power into the DC rotary converter. 1892, Westinghouse installed a generator with a maximum power generation capacity of 1000 horsepower at the Chicago Expo. From 1894 to 1895, three hydro-generators were installed in Niagara Falls, each with a power generation capacity of 5000 HP. 1892, at the urging of Charles Coffin, Edison General Electric Company and Thomson Houston Company merged to form General Electric Company. Elihu Thomson invented the wattmeter and the resistance method of electric welding.

Mankind began to enter the electric power age.