电容过程成像中电容测量方法的比较研究

电容过程成像系统所测量的电容变化量非常微弱，极难检测，且总的杂散电容值又远大于待测电容， 本文分析了ECT系统中四种微小电容检测电路--带反馈补偿的交流测量电路，自平衡电容测量等电路，并比较了它们的优缺点．

COMPARISON OF CAPACITANCE MEASUREMENT FOR CAPACITANCE TOMOGRAPHY

The capacitance changes is very small and difficult to measure for electrical capacitance tomography (ECT) ,and the total stray capacitance is much larger than the measured capacitance. In this paper three types of low value capacitance measuring circuits, which are most suitable for the use in ECT system, four kinds of circuits such as the AC based circuit with feedback compensation, and the self balancing capacitance measuring circuit are described. The stray immune problem of capacitance measurement is discussed. Their advantages and disadvantages are also compared.