Alternating Current, abbreviations: AC refers to the size and direction of the current varies cyclically, running average over a cycle is zero. Unlike direct current does not change direction over time.
Generally sinusoidal waveform. AC can effectively transmit electricity. But in fact there are other applications of waveform, such as triangular wave, square wave. Mains life is having to use the AC sinusoidal waveform.
Once discovered electromagnetic induction, the method generates an alternating current was known. Early finished by the British Michael Faraday (Michael Faraday) developed with the French Hippolyte Pike Xi (Hippolyte Pixii) at all.
In 1882, the British electrician James Gordon built a large two-phase alternators. Lord Kelvin and Sebastian Fei Landi (Sebastian Ziani de Ferranti) developed early alternators, frequency between 100 Hz to 300 Hz.
In 1891, Nikola Tesla made "high frequency" (15,000 Hz) of the alternator patents.
In 1891, the multi-phase AC generator is used to supply current, alternating current frequency thereafter alternator usually designed Hz to 100 Hz in 16 rooms, with an arc lamp, incandescent lamp or electric motor use.
According to the law of electromagnetic induction, when the magnetic field around the conductor changes, the induced current in the conductor. Normally, rotating magnet called the rotor conductor wound on the core of the coil fixed group, called the stator, a magnetic field when it is over, they generate electricity. It called basic machine to generate AC alternator.
