Brushless motors are a type of motor commonly used in many applications, and magnets are one of their key components. The choice of magnets has a significant impact on the performance, efficiency and stability of the motor. Here are some factors to consider when selecting magnets for use in brushless motors.

1. Magnet material type

Brushless motors usually use permanent magnet materials as magnets, and common permanent magnet materials include neodymium iron boron and samarium cobalt. These materials are suitable for use in motors because of their high magnetic properties and stability.

2. Magnet shape

The shape of the magnet affects the structure and performance of the motor. For example, different shapes of magnets such as round, curved, block, etc. can be used in different types of brushless motors, such as planar internal and external rotor motors and external rotor motors.

The following figure shows the more commonly used brushless motor magnet - neodymium arc segment magnets

3. Performance grades of magnets:

Neodymium powerful magnets usually have different grades of magnetic energy area, which indicate their magnetic properties. Higher grade magnets usually have a higher magnetic energy product and can provide a larger magnetic field in a smaller size. Choosing the right grade of magnet can achieve higher output power in a limited space.

4. Operating temperature:

Brushless motors generate heat during operation, so the magnet's operating temperature stability is important. Ensure that the selected magnet can maintain stable performance when the motor is running, and will not lose its magnetic properties due to the increase in temperature.

5. Magnetic field direction:

The polarity and direction of the magnet have an important impact on the design and performance of the motor, and the magnetic field direction of the motor should be matched with the coil arrangement and control strategy to achieve the desired movement.

6. Corrosion resistance:

If the brushless motor will be used in a humid or corrosive environment, it is important to select a magnet material or surface coating with good corrosion resistance to prevent damage to the magnet.

7. Cost and availability

Different materials and grades of magnets have different prices and availability, and the selection of appropriate magnets should take into account the budget as well as the reliability of the magnet supply.

Taking the above factors into consideration, you should choose the appropriate magnet material, shape and grade according to your brushless motor design needs. If you are not sure how to choose, it is recommended to consult a motor design expert or magnet supplier for more specific advice.

More brushless motor magnet professional introduction;

Temperature requirements for brushless motor magnets

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