ECT System With LSI Capacitance-to-Voltage Converter

The multiphase flow is an exploration research field, which is waited to develop urgently. Process Tomography (PT) technique, which is has been developed rapidly in recent ten years, has great developmental potential and wide industrial application prospect. Electrical Capacitance Tomography (ECT) has many distinct advantages such as low cost, wide application field, simple structure, non-invasive measurement and better safety, ECT has being the most popular research direction and the main development in process tomography technique. There is still a lot of work to be done before practical use of the technique.The paper introduces the basic principles of tomography, the system constitution, the basic features and developing status. It also analyzes the principle and proposes the mathematical model of sensitivity field, discusses the peculiar advantages and research status of the technique, and then make the object of this dissertation is on the research of 16-electrode Electrical Capacitance Tomography system. The system includes a MCU based data acquiring system, which can communicate with upper computer expediently and fleetly in real time, also advance the speed of data acquisition and processing. At the same time, the corresponding software and hardware design and the debugging has been completed, provides the high quality data for the image reconstruction. To solve the nodes of tiny capacitance measurement in ECT system design, this text gives a general description of LSI Capacitance-to-Digital Converter, and the bring forward the method of capacitance measurement with LSI CDC in Electrical Capacitance Tomography System, sequentially predigest electro circuit of capacitor measurement, and enhance precision.It is an important field to research an appropriate image reconstruction algorithm for ECT technology to actualize a high quality reconstructed image in on-line Electrical Capacitance Tomography System. Based on the widely study of many kinds of image reconstruction algorithm in linear back-projection (LBP) algorithm and iterative algorithm ,the paper researched the Regularization algorithm, gives a reformative Regularization algorithm ,which reduces the calculation to one step, and then partition reconstructed imagine with the Maximal Variance Threshold. At the end the design uses reformative Regularization algorithm in the researched 16-electrode Electrical Capacitance Tomography system.