典型平面涡流应力传感器检测特性的仿真分析

In measuring stress using eddy current, characteristics of eddy current sensors are very important in selecting the appropriate sensor. The characteristics of six planar eddy current stress sensors (circular, elliptical, rectangular, Archimedes spiral, rectangular spiral, and meandering winding magnetometer, MWM) were compared through simulation. An aluminum 6063-T83 plate was used as a sample. Taking the change of electrical conductivity as the simulation parameter of the stress change, taking the induced voltage of the detecting coil as the analysis object, the simulation comparison of the sensor characteristics was carried out from two aspects, the stress measurement sensitivity and the stress direction sensitivity. Results show that, the sensitivities of the six sensors vary with exciting frequency and space between sensor and sample, possessing nearly the same patterns. When there is only single exciting unit in the sensors, the rectangular sensor is the best of all sensors in induced voltage, sensitivity, and ability to distinguish the direction of stress. When there are multiple exciting units, the MWM sensor is the best of those, and the circular sensor and Archimedes spiral sensor nearly could not distinguish the direction of stress. Finally, the abilities to distinguish the stress direction of rectangular and MWM sensors were verified experimentally.