Based on the flow of charge, the electric current is classified into two types, i.e. alternating current (AC) and direct current (DC)
AC Current
The flow of electric charge in a periodically reverse direction is known as alternating current (AC). AC is also referred to as “AC Current”. Although this is technically saying the same thing twice “AC Current”.
An alternating current changes its a direction at a periodic interval of time. The alternating current starts from zero, rises to maximum, decreases to zero, then reverses and reaches a maximum in the opposite direction, then again returns to the original value and repeats this cycle infinitely.
The type of alternating currentwaveform may be sinusoidal, triangular, square, or sawtooth, etc. In most electrical circuits, the typical waveform of alternating current is a sine wave. A typical sine waveform that you might see as an alternating current is shown in the image below.
An alternator can generate an alternating current. The alternator is a special type of electrical generator designed to generate alternating current.
AC electric power is widely used in industrial and residential applications.
DC Current
The flow of electric charge in only one direction is known as direct current (DC). DC is also referred to as “DC Current”. Although this is technically saying the same thing twice “Direct Current ”.
As DC flows only in one direction; hence it is also referred to as unidirectional current. A waveform of a direct current is shown in the image below.
DC can be generated by batteries, fuel cell, thermocouples, solar cells, commutator type electrical generators, etc. An alternating currentcan be converted to direct current by using a rectifier.
DC electric power is generally used in low-voltage applications. Most electronic circuits need a DC power supply for its operations