Difference Between AC Motor and DC Motor (With Table)

Both AC and DC motors are utilised in various applications, but they are not the same. The torque produced by AC motors is alternating current, whereas the torque produced by DC motors is direct current. This distinction is critical in applications where you need to know whether a motor runs on alternating current or direct current.

AC Motor vs DC Motor

The main difference between an AC motor and a DC motor is the type of current that each motor converts into energy. AC motors convert alternating current, and DC motors convert direct current. AC motors are appreciated for their speed control and output range. In contrast, DC motors are noted for their enhanced power output and efficiency.

AC Motor vs DC Motor

Electrical power is converted into mechanical energy by an AC motor, which uses a commutator to generate the current and brushes to transform it into rotational motion. The rotating mass of the motor is connected to a shaft that turns a drive shaft, which transmits the rotational motion to a load.

A DC motor is an electric motor that uses a magnetic field to create motion in a rotating part of the device. It is often used in solenoids, variable speed fans, and flywheels. Direct current (DC) means electricity passes directly from the power source to the device, with minimal or no back-and-forth signal. Electricity flows in a straight line along its path.

Comparison Table Between AC Motor and DC Motor

Parameters of ComparisonAC MotorDC Motor
EfficiencyThe AC motor’s efficiency is reduced due to induction current loss.DC motor is more efficient than AC motor.
Phases of Input FlowSingle-phase and three-phase power can be used to power AC motors.A single-phase power source can only power DC motors.
TypesAC motors are divided into two types: Induction and Synchronous AC motors.DC motors are divided into two types: brushless and brushless.
Characteristics of the ArmatureThe armature of an AC motor remains motionless as the magnetic field spins.The armature moves in DC motors, but the magnetic field remains stationary.
BrushesThere are no brushes in AC motors,. In DC motors, you will find commutators.
CommutatorsCommutators are not present in AC motor.Commutators are present in DC motor.
Uses Large industries are the primary users of these machines.They are primarily found in household appliances.

What is AC Motor?

AC motors use alternating current from an electrical power generator to transform electrical current into mechanical rotational energy. The generator converts mechanical energy into electrical energy then applies it to the motor rotor, causing it to rotate. The rotation of the rotating magnetic field causes the rotor to spin and the shaft to turn.

AC motors are commonly used in industrial machinery, household appliances like fans, blenders, electric drills, and electric vehicles such as trains, buses, and electric trams.

However, if you are in a remote location or do not have the money to get an expensive commercial electrical system set up, using an alternative energy source like solar or wind power can help you maintain reliable electricity at a relatively low cost.

You can still use AC motors for various jobs without having to buy expensive commercial-grade equipment. Instead, you can use small portable devices that convert alternating current (AC) from an electrical power generator into mechanical rotational energy.

These devices include permanent-magnet alternators and conventional AC generators powered by car batteries or solar panels. Both of these are good options if you want to run custom irrigation systems with controllers or other small-scale AC products that require a reliable source of electricity.

What is DC Motor?

A DC motor is a rotary electrical motor that transforms direct current (DC) energy into mechanical energy. It is widely used as an electric motor for small to medium-sized applications.

A DC motor’s simplest form is a single-pole, double-throw (SPDT) type. A single magnetic field separates the two poles, and the armature consists of two circular permanent magnets. A basic DC motor model has four parts: stator, rotor, commutator, and brushes.

 The stator is a ring of steel or other metal forming the magnetic field; the rotor is a ring of metal (generally soft iron or steel) that rotates in the magnetic field; the commutator is a metal strip that connects the poles of the stator and rotor; and the brushes are contacts between the commutator, which generates an electrical current in one direction, and the rotor, which guides current flow and provides torque.

DC motors are often used in applications with little room for movement, like in simple appliances or toys. The rotatory electric motor is used in various applications, from toys to cars. DC motors can be found in many household appliances, such as fans and hair dryers. DC motors are inexpensive, lightweight and easy to produce in large quantities.

DC motors are often used to power small machines because they have a powerful output at low speeds and have a wide range of speeds. However, they do not tolerate high speeds very well, so they are not widely used for industrial equipment.

Main Differences Between AC Motor and DC Motor 

  1. AC motors are split into brushless and brushless, whereas DC motors are separated into two types: brushless and brushless.
  2. An AC motor’s armature remains static as the magnetic field spins. DC motors, on the other hand, have a rotating armature but a stationary magnetic field.
  3. There are no Brushes present in AC motors, but Brushes are present in DC motors.
  4. 4. Single-phase or three-phase electricity can be used to power AC motors. However, DC motors can only be supplied by a single-phase power source.
  5. AC motors are typically used in large enterprises, whereas DC motors are primarily used in domestic products.
  6. There are no commutators present in AC motors, but commutators are present in DC motors.

Conclusion

Although DC motors use more electricity, AC motors are more efficient and provide more torque. As a result, they are more typically seen in electric vehicles like cars and scooters than their DC counterparts. 

Other devices, such as computers and printers, can include AC motors (and motor controllers). However, DC motors are not commonly employed in these applications. The torque produced by AC motors is alternating current, whereas the torque produced by DC motors is direct current.

References 

  1. https://arc.aiaa.org/doi/pdf/10.2514/6.2018-4584
  2. https://www.jstage.jst.go.jp/article/ieejjia/2/1/2_79/_article/-char/ja/