The alternating current arose in 1832, when the Frenchman Hippolyte Pixxii made use of the principle of electromagnetic induction of Michael Faraday. Nikola Tesla and other scholars, years after the invention of alternating current, improved the AC distribution system as well as some innovations that made its application more practical.
In this way, the polyphase system came to dominate, thanks to the advantages of reduced cost, practicality and efficiency in relation to the direct current. The alternating current or alternating current consists of an electric current, in which its direction can vary in time, unlike the direct current, that its sense is constant in the course of all the time. H18005
The usual waveform in an alternating current power circuit is sinusoidal in the form of power transmission being considered more effective. However, in some specific applications, different waveforms are used, for example, triangular or square waves. While the source of direct current is made by the positive and negative poles, the alternating current is composed of phases, and in most cases, by the neutral wire.