高精度电容式位移传感器关键技术的研究

Research of Key Technology for High Precision Capacitive Displacement Sensor

研制了一种高精度电容式位移传感器，详细介绍了该传感器的基本工作原理和提高传感器精度的关键技术，对电容传感器的具体电路进行模块化设计；分析影响传感器精度与稳定性的因素，采用完全等电位屏蔽技术，对正弦激励电路、参考电容、传感器测头、电源进行技术改进，最后对电容传感器进行系统标定。实验证明：该传感器测量范围为±5-±40μm，测量分辨率〈10nm，测量精度〈20nm．

High precision capacitive displacement sensor was designed. The fundamental principle and key technologies to improve the precision of sensor were introduced particularly. Following the design of modularized circuitry was conduced. Analyzing the elements that contribute to precision and stability of the sensor, complete equipotenfial screening technology was applied, and improved technologies applying on sine excitation circuitry, reference capacitance, polar plate and power supply were proposed. Finally, system calibration to capacitive sensor were conduced. Experimental results show that measurement range from ± 5 -±40μm,reselution better than 10 nm,precision better than 20 nm can be achieved.