Self-compensating magnetoelastic torque sensor system

摘要

A magnetic torque transducer arrangement for self-compensating effects of external magnetic sources and temperature offset includes a shaft with at least one magnetized zone, at least one active magnetic field sensor and at least one passive magnetic field sensor disposed in such a way that the active field sensor is always in a position with higher magnetic field strength arising from applied torque than that of the passive sensor. Passive field sensors may also be placed on both sides of the active field sensor, or on only one side of the active field sensor. The transducer output is obtained by subtracting the output of the passive field sensors from that of the active field sensor, thus canceling out the effect of the interfering magnetic field flux and temperature offset on the torque transducer, and partially filtering out the temperature sensitivity drift and rotational dependant signal.