一种电容层析成像系统电极组合激励测量方法

针对电容层析成像图像重建具有非线性不适定性的问题,提出了8组24电极旋转激励测量方案,并与传统12电极电容层析成像传感器进行了对比分析,包括电容值大小及其动态范围、敏感场分布均匀性以及重建图像质量。应用COMSOL软件及Matlab软件对两种传感器激励模式进行仿真,结果表明:所提出的8组电极旋转激励测量模式,其电容独立测量数与传统12电极传感器相近,可较好地保证实时成像速度,测量电容值较大且动态范围较小,降低了信号检测电路设计难度,测量区域灵敏场均匀性有所改善,对中心物体的成像质量明显提高。

An Exciting-measuring Mode for Electrical CapacitanceTomography System

In order to reduce the nonlinear and ill-posed inverse problem of electrical capacitance tomography (ECT), one kind of exciting-measuring mode is presented for ECT sensor consisting of 24 segments linked in 8 groups, treated as single, extremely broad electrodes forming 8-electrode sensor.The values and the dynamic range of measured capacitance data, the uniformity of sensitivity distribution and the reconstructed images of different flow regimes were compared with conventional exciting-measuring mode 12-electrode sensor.Two kinds of sensors were simulated by utilizing COMSOL and Matlab software.The simulation results showed that for the presented exciting-measuring mode, the number of independent measurements close to that of 12-electrode sensor, which will not cause the decrease of real-time reconstruction speed.However, the measured capacitance valves are larger and its dynamic range is smaller, which can reduce the difficulty of measurement circuit.Meanwhile, the sensitivity distribution is more uniform and the quality of reconstructed images for the objects in the central locations is improved obviously.