AC vs DC Motor: Difference and Comparison

Electric motors are used to convert electrical energy to mechanical energy. The AC and DC motors are two types of electric motors.

Key Takeaways

  1. AC motors run on alternating current, while DC motors use direct current.
  2. AC motors are more energy-efficient and require less maintenance, while DC motors offer greater speed control and a simpler design.
  3. AC motors dominate industrial applications, while DC motors are common in small appliances and electronic devices.

AC vs DC Motor

The difference between AC and DC motors is that they use different types of current. The AC motor uses an alternative current and turns it into energy by the electric motor.

AC vs DC Motor

Science Quiz

Test your knowledge about topics related to science

1 / 10

A passenger in a moving bus is thrown forward when the bus suddenly stops. This is explained

2 / 10

Quartz crystals normally used in quartz clocks etc. is chemically

3 / 10

What is laughing gas?

4 / 10

Balloons are filled with

5 / 10

What is the scientific name of frog?

6 / 10

Name the metal which is most ductile?

7 / 10

Non-stick cooking utensils are coated with

8 / 10

Name the fabric which is used in making bulletproof jackets?

9 / 10

What is the scientific name of humans?

10 / 10

Acid turns blue litmus paper into which color?

Your score is


AC motor is a powerful motor and is always preferred over DC motor because of their efficiency and easy availability. The power for the AC motor is supplied from the AC.

The DC motor is an electric machine or motor that uses direct current and converts electrical energy to mechanical energy. Various projects and experiments use DC motors as the source.

Comparison Table

Parameters of ComparisonAC MotorDC Motor
Power sourceThe AC motors use alternating current only and do not work with anything else. The alternative current goes through the electric motor’s input and is converted as mechanical energy.The DC motors derive their current from direct current. Some of the power sources of direct current are the DC power supply and batteries. The AC to DC converter is occasionally used.
UsageThe AC motors are specifically utilized in circumstances where powerful performance is required. Also, it is used for longer periods.The DC motors come in handy in circumstances that require more motor speed. The motor speed can be limited externally.
Life expectancyThe AC motors have a longer life span. As the AC motors do not possess commutators and brushes, they have a longer life expectancy period.The DC motors have a short and limited life span. As the DC motors possess commutators and brushes, the life expectancy is limited.
Speed controlThe AC motor’s speed can be controlled by changing the frequency. This is performed by using an adjustable frequency drive control.The DC motor’s speed can be controlled by changing the armature winding’s current. By varying the armature winding’s current, DC motors can be kept in control.
EfficiencyThe AC motors are less efficient than DC motors. As AC motors have induction current loss and possess a motor slip, the efficiency is reduced.The DC motors are more efficient than AC motors. As DC motors do not have any induction current loss or a motor slip, the efficiency of DC motors is high.

What is AC Motor?

AC motor means Alternating current motor. AC motors get supplied with power from the Alternative current.

To start the operation, the AC motor requires equipment like a capacitor. AC motor’s speed can be controlled by differing the current flow’s frequency with the help of variable frequency drive.

AC motors have two types. They are Synchronous motors and Asynchronous motors.

On the other hand, Asynchronous motor drives at a speed less than that of a synchronous motor. It is also known as an induction motor. Asynchronous motor is used frequently due to its reliability and usefulness.

ac motor

What is DC Motor?

The DC motor is a rotary electric motor used for the conversion of energy. The DC motor is also known as the direct current motor.

The DC motors are the product of the early 19th century. When it was invented in the 1840s, dc motors were unsuccessful. The heavy battery usage required to run these dc motors was expensive and was of low quality. With the advent of rechargeable batteries, DC motors were used extensively.

An interaction occurs between an electric field and a magnetic field. A new mechanical force is produced out of the interaction between those two fields.

Fleming’s left-hand rule explains the direction of the motor’s rotation. According to the rule, the middle, index and thumb fingers are extended mutually perpendicular.

dc motor

Main Differences Between AC and DC Motor

  1. The AC motors use alternating current, which is used to turn into mechanical current. The DC motors use direct current, which is converted into mechanical current.
  2. The AC motors have three different input terminals, as RYB are present within them. The DC motors have two different input terminals, as positive and negative are present within them.
  3. The AC motors are controllable by changing the frequency of the motor. The DC motors can be limited by changing the armature winding’s current.
  4. The AC motors are very slow in responding to the change in load. The DC motors are very quick in responding to the change in load.
  5. The AC motors are less efficient because of the induction current loss and motor slip. The DC motors are more efficient because there is no induction current loss and motor slip.
Difference Between AC and DC Motor

Last Updated : 30 July, 2023

dot 1
One request?

I’ve put so much effort writing this blog post to provide value to you. It’ll be very helpful for me, if you consider sharing it on social media or with your friends/family. SHARING IS ♥️

Leave a Comment

Your email address will not be published. Required fields are marked *

Want to save this article for later? Click the heart in the bottom right corner to save to your own articles box!