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AC and DC motors

In this article we will learn about motors and its type, AC and DC motor, types of it. Here we also discuss some important questions.

A device that converts electrical energy into mechanical energy is known as an electrical motor. It operates on the idea that when a current conductor is placed in a magnetic field, the motor’s engine converts into an electrochemical system, converting electrical energy to mechanical energy. We’ll look at many sorts of motors in this post, including AC motors, DC motors, and others.


A motor is a machine that converts electrical energy into mechanical energy. When the current and magnetic field in the motor interact, a force is generated in the perpendicular direction to the current and magnetic field. A motor is a rotating device that produces force.

Motors type:

AC and DC motors are the two types of motors that are commonly used. On the one hand, when AC motors require little power at first and are flexible in terms of speed control, DC motors, on the other hand, are simple to install and have cheap initial power unit costs, making them popular. AC and DC motors are further divided into the following categories:

AC motors

Motors that are synchronized

Asynchronous Motors are a type of motor that runs in a (Induction)

  1. Single Phase

  2. Three Phase

DC motors

Brushless \Brushed

  1. Compound Wound

  2. Permanent Magnet

  3. Series Wound

  4. Shunt Wound

AC motors

When compared to DC Motors, AC Motors offer more flexibility and have a bigger installed base. The following are some of their characteristics:

🡪When starting an AC motor, it is necessary to use a little amount of electricity.

🡪In AC motors, the beginning current can be regulated.

🡪They also have a lot of speed control flexibility.

🡪They have torque restrictions that can be adjusted.

🡪AC motors can have their operating speeds changed.

🡪While working, they have a controlled rate of acceleration.

🡪They have the ability to minimize power line disruptions.

Ac motors type


The rotor rotation is synced with the frequency of the supply current, and the speed of synchronous AC motors remains constant even with variable current demands. Because of this benefit, this sort of motor is suitable for moving pieces of equipment at a consistent speed and is used in high-precision positioning devices such as machines, instruments, robotics, and so on.                 

Asynchronicity (Induction)

The AC induction motor’s engine operates on the principle of electromagnetic induction. These motors are the most common type of AC motor due to its load capability. The magnetic field of the stator generates induction, which results in the production of an electric current and torque. They are further divided into two categories:

🡪Motors that are only in one phase (single phase)

They’re commonly seen in domestic appliances that require lesser loads.

🡪Motors with three phases (triple-phase)

They’re employed in a variety of industries for things like lifting gears and conveyor belts.

Dc motors

When compared to AC motors, DC motors were the first type of motor to be widely employed due to its inexpensive initial prices, which included drives and motors. However, in high-power scenarios, the system’s total maintenance expenses increased. DC motors have the following characteristics:

🡪The voltage supplied can be changed to alter the speed of the DC motor.

🡪They are simple to set up.

🡪Their torque-speed curve is linear.

🡪They have the ability to be quickly started, halted, reversed, or accelerated.

🡪DC motors have a wide range of speed control.

🡪They have a lot of torque when they first start up.

Dc motors type

There are two types of DC motor: –

Motors with no brushes (means brushless motors)

Brushless DC Motors offer a longer life cycle and a more straightforward design. They are low-maintenance and extremely efficient. They’re found in appliances that require position and speed control, such as fans, pumps, and compressors. Brushless motors are used in stepper motors.

Motors that have been brushed (means brushed motors)

Traditionally, brushed motors have been utilized for a range of fundamental applications. They’re found in appliances that have a simple control system. They’re employed in both fundamental industrial and consumer applications. These are further divided into four categories:

Wound in a Series

The field and series windings are connected in series in series wound DC motors. The voltage supplied can be changed to alter the motor’s speed. The motor, on the other hand, has poor speed control, and the speed can decline as the torque increases. Because of their large beginning torque, these motors are commonly employed in lifts and cranes, automobiles, and hoists, among other applications. Series Wound

Shunt Broken ribs

The field and series windings of shunt wound DC motors are connected parallel to each other. It has a single supply voltage and can give high torque without reducing engine speed by raising engine current. It’s employed in vacuum cleaners, grinders, conveyors, and other machines because of its medium starting torque when compared to continuous speed.          

                                               Shunt Wound  

Compound Broken ribs

A compound wound DC motor combines the advantages of both series and shunt wound motors. The polarity of shunt winding is also added to the polarity of the series field. Even when the system’s load varies, it functions smoothly. It is utilized in circular saws, rotary presses, centrifugal pumps, elevators, and other machines that require a high starting torque.         Compound Wound

Magnetism that is permanent

Permanent magnets are utilized in servo systems, robotics, and other applications where precision control and low torque are required.


A motor is a machine that converts electrical energy into mechanical energy. A device that converts electrical energy into mechanical energy is known as an electrical motor. AC and DC motors are the two types of motors that are commonly used.


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