Design of Fault-Tolerant Inductive Position Sensor

고장 허용 유도형 위치 센서 설계

  • 백승국 (충남대학교 BK21 메카트로닉스사업단) ;
  • 박병철 (한국전력 연구원) ;
  • 노명규 (충남대학교 메카트로닉스공학)
  • Published : 2008.03.01


The position sensors used in a magnetic bearing system are desirable to provide some degree of fault-tolerance as the rotor position is necessary for the feedback control to overcome the open-loop instability. In this paper, we propose an inductive position sensor that can cope with a partial fault in the sensor. The sensor has multiple poles which can be combined to sense the in-plane motion of the rotor. When a high-frequency voltage signal drives each pole of the sensor, the resulting current in the sensor coil contains information regarding the rotor position. The signal processing circuit of the sensor extracts this position information. In this paper, we used the magnetic circuit model of the sensor that shows the analytical relationship between the sensor output and the rotor motion. The multi-polar structure of the sensor makes it possible to introduce redundancy which can be exploited for fault-tolerant operation. The proposed sensor is applied to a magnetically levitated turbo-molecular vacuum pump. Experimental results validate the fault-tolerance algorithm.


Fault-Tolerance;Inductive Position Sensor


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