高温磁悬浮轴承用位移传感器的研究

针对差动变压器式位移传感器的性能及其在高温磁悬浮轴承中的应用，对环境温度升高影响差动变压器式位移传感器（DTDS）性能的机理和特征以及所采用的温度补偿技术进行了研究。采用比值方式的处理电路以及加入补偿电阻的方法改善了温度升高所带来位移传感器灵敏度升高、温度漂移和时间漂移的问题。对不同温度下的差动变压器式位移传感器进行标定得到了位移传感器的动静态性能，并将其应用到单自由度高温磁悬浮轴承（HTAMB）试验台上进行静态和模拟动态悬浮。研究结果表明，环境温度为550 ℃，被测物体移动范围在-0.35~+0.35 mm时，位移传感器的灵敏度在19.62 mV/μm，线性度为±0.74%，迟滞性为±0.40%，重复性为±0.97%，传感器截止频率在800 Hz左右；在单自由度高温磁悬浮轴承试验台上使用所研制的高温位移传感器，能实现被悬浮物体的稳定悬浮。

Research on Displacement Sensor of High Temperature Active Magnetic Bearing

The influence of high operating temperature on the differential transformer displacement sensor (DTDS) mechanism and characteristics and the following temperature compensation technology are mainly analyzed in view of the performance of DTDS and its application in high temperature active magnetic bearing (HTAMB). The technical problems of sensor sensitivity increase, temperature and time drift caused by the temperature rise are improved through the processing circuit of ratio mode and compensation resistance. The DTDS at high temperature is statically and dynamically calibrated and applied to a single degree-of-freedom (DOF) HTAMB system for static and dynamic simulation suspension. When the measurement range is -0.35-+0.35 mm with the working temperature 550 ℃, the DTDS has the following characteristics: sensitivity is 19.62 mV/μm, linearity is ±0.74%, hysteresis is ±0.40%, repeatability is ±0.97% and the cutoff frequency reaches 800 Hz. Finally, this DTDS is successfully used in a DOF HTAMB test bed. The results provide promotion for the HTAMB application in more-electric gas turbine engines system.