Detection of brushless motor rotation

A brushless motor, the mainstream at present, has achieved downsizing and loss reduction by incorporating Hall effect ICs, providing the highly accurate rotation control.This is the most popular method for small-sized motors. We introduce the most typical hall motor applications here.

 

Detection of motor rotation with Hall effect IC

Advantages of using Hall effect IC
High durability due to non-contact detection
Highly resistant to contamination such as dust, dirt, or oil, because of detection of magnetism
Downsizing, weight reduction, and loss reduction are possible.

 

Principle

A Hall effect IC can obtain the ON/OFF digital output corresponding to the strength of the magnetic field and uses these characteristics to detect the rotor position.If one or multiple Hall effect ICs are allocated in parallel on the stator side opposite to the magnet pole of the motor rotor, the rotor position can be detected from the magnet allocation, enabling the detection of the rotation.

 

Configuration examples

Here, the typical example in which three Hall effect ICs are placed at locations offset by 60 degrees each other on a 4-pole rotor and the index detection example.

Configuration 1
A 4-pole rotor and three Hall effect ICs are used to detect the rotation.

   Special features
A maintenance-free motor can be implemented.
Application-specific design is possible.
Stable activation and low vibration allow a quiet operation.  

 

 

 

 

 

                                                             

  

 

 

 

 

 

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