About Permanent Magnet Synchronous Motor (PMSM) | New Topic [2024]

In this note, we will learn about Permanent Magnet Synchronous Motor or PMSM, Construction of Permanent Magnet Synchronous Motor, Working Principle of Permanent Magnet Synchronous Motor, and Characteristics as well. Welcome to Poly Notes Hub, a leading website for Engineering Notes.

Author Name: Arun Paul.

What is Permanent Magnet Synchronous Motor?

A Permanent Magnet Synchronous Motor (PMSM) is an electric motor with permanent magnets incorporated or attached to the rotor to generate a magnetic field. This magnetic field interacts with the magnetic field generated by the stator (the motor’s stationary component) to produce rotational motion. PMSMs are noted for their high efficiency, precise control, and small design, making them ideal for a variety of applications such as industrial machinery, electric vehicles, robotics, and HVAC systems. They are popular in modern electrical systems due to their high power density, low maintenance requirements, smooth operation, and accurate speed control capabilities.

Construction of PMSM

• A PMSM has two primary components: the stator and the rotor.
• The stator is composed of a stationary exterior casing consisting of laminated steel sheets. Inside the stator, wire coils are placed in certain configurations to generate a magnetic field when an electric current flows through them.
• The rotor, or rotating part of the motor, comprises permanent magnets that are either integrated in its structure or attached to its surface. Magnets are often made of materials such as neodymium-iron-boron (NdFeB) or samarium-cobalt (SmCo), which create powerful magnetic fields.

Working Principle of PMSM

• When an electric current is passed through the stator windings, it produces a rotating magnetic field.
• The permanent magnets on the rotor are drawn to the magnetic field generated by the stator, causing the rotor to rotate in lockstep with the rotating field.
• The rotor creates mechanical power, which can be utilized to drive a variety of mechanical loads.
• The frequency of the electric current provided to the stator windings determines the motor’s speed, as does the number of pole pairs.

Characteristics of PMSM

1. High Efficiency: These motors are noted for their great efficiency, which frequently exceeds 90%, due to reduced energy losses caused by the absence of rotor copper losses (as in induction motors) and low friction losses.
2. High Power Density: It is offer a high power-to-weight ratio, which makes them ideal for situations where space and weight are limited.
3. Speed Control: It is provide precise speed control and strong dynamic response, making them perfect for applications that require precision speed and position control.
4. Low Maintenance: It’s require less maintenance than brushed DC motors since they lack brushes and commutators.
5. High Torque Density: It is may generate strong torque at low speeds, making them ideal for applications that require high starting torque.

Advantages of PMSM

Below, we listed some advantages of Permanent Magnet Synchronous Motor –

1. It offers high efficiency.
2. These motors are small in size.
3. These motors are offer smooth operation.
4. Low maintenance cost as well.

Disadvantages of PMSM

Below, we listed some disadvantages of Permanent Magnet Synchronous Motor –

1. Very Expensive.
2. Difficult to start.

Applications of PMSM

Below, we listed some applications of Permanent Magnet Synchronous Motor –

1. Used in Air Conditioner.
2. Used in Washing Machines
3. Used in Servo drives.
4. Used in Automotive.
5. Used in Machine tools. etc.