传感技术学报
傳感技術學報
전감기술학보
Journal of Transduction Technology
2010年
3期
341-346
,共6页
微电容检测%频分复用%检测灵敏度%零位稳定性%静电悬浮
微電容檢測%頻分複用%檢測靈敏度%零位穩定性%靜電懸浮
미전용검측%빈분복용%검측령민도%령위은정성%정전현부
capacitance detection%frequency multiplexing%detecting sensitivity%zero stability%electrostatic levitation
为使静电悬浮微电机的环形转子稳定悬浮在定子电极腔体的几何中心,需要采用差动电容式传感器检测转子沿五个自由度的运动,然后通过静电悬浮控制系统实现有源静电支承.根据频分复用原理,设计了一套可检测悬浮式转子五个自由度运动的微电容检测电路.采用多路高频正弦信号作为载波加载至与各自由度对应的控制/检测电极上,通过公共电极输出反映转子沿各自由度位移变化的调幅信号,然后经过交流放大、相敏解调、低通滤波后得到各自由度位移检测信号.文中介绍了微电容检测电路的组成及原理,分析了电路特性,给出了x轴检测电路的测试结果.实验表明,检测电路的灵敏度为23.3 V/pF,通频带为10.58 kHz,零位稳定性优于0.1 mV.
為使靜電懸浮微電機的環形轉子穩定懸浮在定子電極腔體的幾何中心,需要採用差動電容式傳感器檢測轉子沿五箇自由度的運動,然後通過靜電懸浮控製繫統實現有源靜電支承.根據頻分複用原理,設計瞭一套可檢測懸浮式轉子五箇自由度運動的微電容檢測電路.採用多路高頻正絃信號作為載波加載至與各自由度對應的控製/檢測電極上,通過公共電極輸齣反映轉子沿各自由度位移變化的調幅信號,然後經過交流放大、相敏解調、低通濾波後得到各自由度位移檢測信號.文中介紹瞭微電容檢測電路的組成及原理,分析瞭電路特性,給齣瞭x軸檢測電路的測試結果.實驗錶明,檢測電路的靈敏度為23.3 V/pF,通頻帶為10.58 kHz,零位穩定性優于0.1 mV.
위사정전현부미전궤적배형전자은정현부재정자전겁강체적궤하중심,수요채용차동전용식전감기검측전자연오개자유도적운동,연후통과정전현부공제계통실현유원정전지승.근거빈분복용원리,설계료일투가검측현부식전자오개자유도운동적미전용검측전로.채용다로고빈정현신호작위재파가재지여각자유도대응적공제/검측전겁상,통과공공전겁수출반영전자연각자유도위이변화적조폭신호,연후경과교류방대、상민해조、저통려파후득도각자유도위이검측신호.문중개소료미전용검측전로적조성급원리,분석료전로특성,급출료x축검측전로적측시결과.실험표명,검측전로적령민도위23.3 V/pF,통빈대위10.58 kHz,령위은정성우우0.1 mV.
To maintain the ring shaped microrotor electrostatically suspended in the geometric center of the cavity shaped by the stator electrodes, a set of differential capacitance-based position sensors is used to sense the rotor's mo-tion in five degrees of freedom (DOFs) and utilized to realize active electrostatic suspension. Based on frequency multiplexing method, a set of micro capacitance detecting circuits is presented with an aim to sense the motion of the motor in five DOFs. By applying high-frequency sinusoidal carrier to associated control/sensing electrodes, an ampli-tude-modulated signal which indicates the rotor's position in each DOF is formed from the common electrodes. The amplitude-modulated signals are then amplified, demodulated and low-pass filtered sequentially in order to obtain a readout voltage of the rotor position. The paper describes the operating principle, the design and the performance e-valuation in both simulation and experiment. The experimental results show that the sensitivity is 23.3 V/pF, the bandwidth is 10.58 kHz and the zero stability is less than 0.1 mV.