Research on Non-contact Torque Sensing Method by Magnetoelastic Effect

Torque measurement is widely used in the field of modern machinery industry, and plays an important role in the vehicle, tunnage, energy regeneration, petroleum and other fields. However, the existing torque measurement methods have some limitations in the face of complex conditions. Therefore, a new means based on self-inductance coils has a high research significance. This study investigated the sensing principle of self-inductance coil and the torque and deduced the relationship between the permeability u of soft magnetic material and self-inductance coefficient L. And the theoretical model of torque measurement based on self-inductance coefficient is established by using L as the new parameter to characterize the torque. We obtained experimental data through building experimental platform and conducting torque tests. The result shows the maximum non-linear error is 2.83%, the sensitivity is 0.107 uH/Nm, and the maximum repeatability error is 2.68% FS. This method of measuring the torque of the shaft by measuring the self-inductance coefficient is a new exploration and breakthrough of the problem of magnetoelastic torque measurement.