可溯源至质量的静电力复现与测量技术

Electrostatic force reproducing and measurement technology traceable to mass

为实现10-5N以下微小力值的测量及溯源,提出了一种高精度、可溯源至质量的微小力值测量系统,采用受控静电力发生装置复现微小力值,其基本工作原理是基于一种精密设计的圆柱形电容器,电容器内外电极同轴,外电极固定不动作为参考电极,内电极由弹性机构支撑和导向,通过改变内外电极间的电压产生静电力,从而将力学量追溯至电容及电压等电学量,利用砝码质量与静电力平衡的原理,可以实现微小力值的溯源。实验结果表明：电容变化梯度为0.82 pF/mm,完全可以复现10-6~10-9N范围内的静电力。

To realize the measurement and traceability of micro force value below 10-5 N,a micro force measuring system traceable to mass standard with high precision is proposed.A controlled electrostatic force generator is adopted to reproduce micro force.The basic working principle is based on a precisely designed cylindrical capacitor with the outer electrode serving as the reference and the inner electrode suspended and guided by a rectilinear flexure mechanism.An electrostatic force is generated by the voltage between the electrodes so that mechanical quantity is linked to electrical capacity.The capacitor can be used in a null-displacement mode to compare the electrostatic force with the force generated by the calibrated deadweight of a nominal mass.Experiments show that the capacitance change gradient is 0.82 pF/mm so that the electrostatic force in the range of 10-6～10-9 N can be reproduced completely.