The Improvement of Dual-Plane ERT System by Parallel Data Acquisition Method

C. Tan, F. Dong, B. Wang

School of Electrical Engineering and Automation, Tianjin University, Tianjin, China Tianjin Key Laboratory of Process Measurement and Control, Tianjin, China

Tel: 86-22-27890276, Fax: 86-22-27892055, Email: fdong@tju.edu.cn

ABSTRACT

Electrical resistance tomography (ERT) is a kind of Process Tomography (PT) which is based on the theory of electromagnetic fields and the principle of electrical sensitivity. It has an extensive application prospect in industrial processes. However, it is restricted by the precision, speed and computational capability of existing systems.

According to the operating principle of ERT system, the measurement precision and error closely relate to the systems real-time performance and the performance is mainly restricted by the DAS module. In order to improve the operational speed, the scheme of a parallel dual-plane ERT system is brought out. This new system is based on parallel data-acquisition and processing, it measures the boundary voltages of 16 electrodes synchronously. The digital I/O card and high speed A/D transition card are implemented in this system to reduce the switch time of the measuring signal and to improve system performance. In adjacent exciting strategies and alternate electrode plane selection, this system can theoretically acquire at least 300 frames of cross-section per second.

Keywords Dual-plane, electrical resistance tomography, parallel data acquisition, two-phase flow measurement