Why do we use AC or DC power

Why_Do_We_Use_AC_or_DC_Power.pdf

Better understand why we use AC and DC power in various applications

AC Power

• When power is generated, it is almost always created in the form of AC Power
• AC power is cheaper to generate and send through high voltage power lines
• Converted AC power up or down is much easier with the help of a transformer
• AC power can flow both from positive to negative

Transcript:

[0m:4s] Hi I’m Josh Bloom, welcome to another video in the RSP Supply education series. If you find that you like these videos, it certainly helps us out if you could give us a big thumbs up and subscribe to our channel.
[0m:13s] In today's, video we're going to discuss the two different types of power that we use every day in all sorts of electrical applications: AC power and DC power. More specifically, we want to talk about why we use AC or DC power in various different types of applications. In many cases, you may know that you need DC power for your specific scenario, or maybe a transformer to change voltage needed for a specific situation. But why are these changes necessary? Our hope is that by the end of this video you will have a better understanding of why we use components such as transformers or power supplies and power converters in so many different electrical systems that we find today.
[0m:55s] Let's first discuss the basic differences between AC power and DC power.
[1m:0s] Electrical current is the flow of charged particles or specifically, in a case of AC and DC, the flow of electrons. The main difference between AC and DC power is the actual direction of the electron flow.
[1m:14s] DC power sees current moving in one direction and is constant to better illustrate the constant nature of DC power, you can look at a graph. DC power will look like a straight line moving from left to right as you can see here.
[1m:30s] AC power, on the other hand, changes constantly over time. In this case, current can flow in both a positive and negative direction. On a graph, this current flow looks like a sine wave going up and down alternating between positive and negative flow, hence the alternating current
[1m:48s] as you can see here.
[1m:50s] So, let's talk more about AC power and why it is used where it is.

[1m:54s] When power is generated, in almost all cases, it is generated in the form of AC power,
[2m:1s] which is one of the many reasons why it has become the more predominant form of power that is used today.
[2m:6s] We have the ability to transmit AC power at very high voltages and lower current levels over long distances.
[2m:14s] This makes it easy to take power that is being generated and send it to locations all over the world.
[2m:21s] The voltage levels generated with AC power can be easily changed up or down with the help of a transformer, which is a relatively inexpensive and mechanically simple device.
[2m:33s] With the ability to change voltage levels, we can easily scale the amount of power that is needed in different applications. For example,
[2m:42s] the power that is provided to our homes comes in the form of AC power,
[2m:47s] typically between 120 and 240 volts. Devices that can be used with AC power are not affected by the alternating characteristics of this form of power. Some common examples are light bulbs, many of the heating elements, AC Motors, et cetera. However, some electrical devices are affected by the alternating current, in which case, a different type of power is needed:
[3m:11s] DC power.
[3m:12s] Because DC power is more difficult to generate and because it is more difficult and expensive to convert AC power to DC power, it is not commonly used as the main power source for most applications. However, it is widely used in many different scenarios and is converted one necessary.
[3m:32s] It is common to see DC power being used in more complex electrical circuits. More specifically,
[3m:39s] DC power will be used when electrical components require some type of microchip or processor. The nature of these microchips do not allow them to function with current that alternates back and forth from positive to negative. They need a constant steady voltage source that DC power can provide. This is why the more intelligent electrical equipment that you have is typically being supplied DC power.
[4m:4s] Even in devices such as computers and televisions that are being supplied AC power, they actually are using DC power. These devices convert the AC power to DC for the components in that device that cannot operate with AC power.
[4m:20s] DC power is also used in many other applications, such as charging batteries, which supply DC power, many low voltage applications, and DC motors. So while more difficult to generate DC power is widely used, especially in more complex electrical circuitry where it is an absolute necessity. As you will commonly see, both forms of power will be used simultaneously in many different applications.
[4m:46s] For example, in an industrial control cabinet, you will typically see AC power being supplied which will power some of the components within the panel. Specifically, components that are not affected by the alternated characteristics of AC power.
[5m:0s] You will then see AC power being converted to DC power for devices that are more complex and have some type of microchip or processor that require DC power to function properly. So to briefly summarize, AC power is a much more common type of power that we use today. However, it is often converted to DC power for more complex electrical components that require DC power. For a full line of electrical components and thousands of other products, please go to our website. For more information or other educational videos, go to RSPSupply.com, the Internet's top source for industrial hardware. Also, don't forget: like and subscribe.