The direction of DC voltage is unchanged, while the direction of AC voltage is constantly changing.
Alternating current (AC), also called alternating current (AC), refers to alternating current whose direction changes periodically at any time, and the most basic form is sinusoidal current.
The early alternator products were developed by Michael Faraday and Bo Park Jung Su Pixii. Among them, in 1832, Park Jung-su Pixi hippolyte Pixi manufactured the world's first AC motor according to the michael faraday principle.
1882, British electrician James Gordon built a large two-phase alternator. William thomson (1ST Baron Kelvin,1June 26, 824-1June 5438+February 02, 907 17) and Sebastian Ferranti developed an early alternator with a frequency of1. The earliest high-frequency AC motor was born in London in 1838.
189 1 year, nikola tesla of nikola tesla improved one of the "high frequency" (15000 Hz) alternators and obtained the patent number.