AC vs. DC Motor: What’s the Difference Between Them?

Are you looking for a new motor for an application or piece of construction equipment? Before making any purchases, you must know whether you need to buy an AC motor or a DC motor.

Both types of motors have practical uses in many industries. However, they differ in cost, efficiency, reliability, and performance. By assessing your project requirements, you will know the best motor for you using this guide.

Keep reading to learn about the differences between an AC and a DC motor. 

AC Motor

AC means alternating current. An AC motor uses AC power which reverses the current direction, alternating between positive and negative. 

There are two major types of AC motors — synchronous and induction. 

The synchronous motor rotates at the same rate as the frequency of the supply current. 

The induction motor is the most common type of AC motor. The output rotation is proportional to the applied frequency of the alternate current. Electromagnetic induction creates the electric current that turns the rotor. 

AC motors are robust, durable, and affordable. In addition, they have a longer lifespan and lower repair costs than DC motors.

AC motors are used in large-scale, continuous-speed applications where the motor speed is slow to medium. This is because they are resistant and slow to respond to changes in speed when the load changes. 

AC motors are best for applications that need high speed and variable torque. They tend to lose torque at higher speeds.

DC Motor

On the other hand, a DC motor uses DC power. DC means direct current. The power flows in one direction, like in a battery. As a result, DC motors are usually more efficient than AC motors.

Additionally, they are also more expensive and have high repair costs.

There are also two major types of DC motors — brushed and brushless. 

Brushed motors use a carbon brush to conduct electricity through an internal commutator.

Brushless motors are similar to brushed motors, minus the brushes. Additionally, they have a specialized circuit to control power speed and direction. Furthermore, the motor uses magnets mounted around the rotor to improve efficiency. 

Brushed motors have a shorter life span than brushless motors because of the wear and tear of the brush. But, they have a more straightforward design, so they aren’t as expensive as a brushless motor.

DC motors are quick to respond to a change in the power load. Therefore, they are best for applications that need high torque and variable speed. 

Domestic applications and robotics most often use DC motors because they need fine speed control. 

Get Your Motor Today

With this guide, you can decide if you need an AC motor or a DC motor for your application. If you still aren’t sure, you can also ask a professional for help.

Contact us at KOR-PAK corporation today for more information on the different motors, and receive a free quote! Our experts are here to help you at any time.

Posted in Motors.