典型平面涡流应力传感器检测特性的仿真分析

Simulation Analysis on Testing Characteristics of Typical Planar Eddy Current Stress Sensors

为了在涡流应力检测中正确选择传感器的类型,对6种典型的平面涡流传感器(圆形、椭圆形、矩形、阿基米德螺线、矩形螺线和蜿蜒式)的应力检测特性进行了仿真对比.以铝板为试件,用试件电导率的变化来模拟应力变化;以检测线圈的感应电压为分析对象,从不同激励频率与提离对应力检测灵敏度的影响和传感器对应力方向的敏感性两个方面对各传感器的性能进行了对比.结果表明:随着激励频率和传感器与试件间距的变化,6种传感器的灵敏度有相同的变化规律;在只有单个激励单元的传感器中,矩形传感器的感应电压、灵敏度和对应力方向的敏感性均最好;在具有多个激励单元的传感器中,蜿蜒式传感器的总体性能最好,圆形和阿基米德螺线型传感器对应力的方向不敏感.对矩形和蜿蜒式两种传感器的应力方向敏感性进行了实验验证,结果与仿真分析结果一致.

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.