What is AC/DC Power and Why is it Necessary?

There are two types of electrical current that we use – AC and DC – but only one type comes through the plug sockets in our homes. Because of this, nearly all mains-powered electronic devices include a key component in their design: the AC/DC power supply. In this blog, we will be answering the question ‘what is AC/DC power?’ and exploring why it is required.

What is AC Power?

AC power, also known as alternating current, is a type of electricity where the electric charge periodically changes direction, which also results in the voltage periodically reversing.

AC power is the standard type of electricity that is supplied by the electrical grid and powers our homes and businesses. The voltage and frequency of AC power differ between regions.

The reason AC power is used by the grid is that AC power moves in waves and, as such, can travel much further than DC power. AC power is also easier to generate and cheaper to operate.

Some electrical devices use AC power, but others need the voltage consistency provided by DC power to prevent potential damage to the device.

What is DC Power?

DC power is also known as direct current and gets its name because the electric charge only flows in one direction.

DC power can deliver consistent voltage, which makes it more appropriate for the majority of electrical devices. DC power can only travel short distances, however, which is why it cannot be used by the electrical grid.

DC power doesn’t come from the mains, but it does come from sources such as batteries, solar cells, and fuel cells, as well as AC to DC rectifiers.

Why is it necessary to convert from AC to DC?

As mentioned above, different devices have different power requirements. Many devices need DC power because it delivers a more consistent voltage which is safer for the circuitry. As all power that comes from the electrical grid is AC, devices that require DC power (and are not battery-powered) have to have this mains power converted by an AC/DC converter or rectifier.

An AC/DC power supply or adapter is an electrical device that converts the AC power from the mains into DC power and alters the frequency and voltage to the required levels for the electrical component that needs to be powered.

The current conversion is achieved by a device called a rectifier and the voltage levels are altered by a transformer, which transfers electricity from one circuit to another. An AC/DC power supply can contain multiple rectifiers and transformers.

On any given day, most of us will use both devices that use AC power and devices that use DC power, but as all our mains power is AC, an AC/DC converter is necessary.

What are the applications of AC/DC power?

AC/DC converters are used in a huge range of devices, such as computers, televisions, kitchen appliances and other consumer electronic devices. They are also used in telecommunications, military, and medical equipment, as well as industrial machinery.

One of the main applications of AC/DC power is to charge devices that run on battery power. Common devices such as smartphones and laptops (and pretty much any device with a rechargeable battery) need to store DC power for reliable, consistent voltage. These batteries are charged from the mains supply, where a built-in rectifier converts the AC power into DC.

Hopefully, now you are better informed as to what AC/DC power is, and why AC/DC converters are necessary for the devices that we use every day. You can also view our range of AC/DC power supplies.