SLYT867 June   2025 LDC5072-Q1 , MSPM0G1106 , MSPM0G1107 , MSPM0G1506 , MSPM0G1507 , MSPM0G1518 , MSPM0G1519 , MSPM0G3106 , MSPM0G3106-Q1 , MSPM0G3107 , MSPM0G3107-Q1 , MSPM0G3506 , MSPM0G3506-Q1 , MSPM0G3507 , MSPM0G3507-Q1 , MSPM0G3518 , MSPM0G3518-Q1 , MSPM0G3519 , MSPM0G3519-Q1 , TMAG5170 , TMAG6180-Q1

 

  1.   1
  2. 1 Introduction
  3. 2 Using a position sensor with brushless motor control
  4. 3 Incremental and absolute encoders
  5. 4 FOC motor-control techniques and requirements for encoders
  6. 5 Position sensor technologies
  7. 6 Magnetic position sensors
  8. 7 Linear position example with a 3D Hall-effect linear sensor
  9. 8 Rotary angle example with an AMR sensor
  10. 9 Inductive position sensing
  11. 10Conclusion
  12. 11Additional resources

1 Introduction

Are there still position sensors in motors, since the trend is to go “sensorless”? The full answer to this question is rather convoluted, but basically, position sensors are here to stay. There are applications such as power tools where a sensorless design with a brushless-DC motor block commutation or a field-oriented-control (FOC) brushless-AC motor works without any rotary angle sensor. But the reality is that end equipment such as industrial and humanoid robots, autonomous mobile robots, and linear motor transport systems absolutely need rotary angle or linear position sensors.