Design Of Electrical Resistance Tomography System With Remote High-speed Transmission

Electrical Resistance Tomography(ERT)is a type of process parameter measuring technique,it has the characteristic of simple structure and working principle,low cost,no radiation,rapid response and ability of visualization.It is suitable for the process parameter monitoring of closed pipes and vessels in the industrial production process.However,the existing ERT systems are mainly used the design scheme of laboratory instrumentation,and the data acquisition and processing unit uses only the local integration mode.It doesn't have long-distance data transmission function,are unable to connect with industrial control systems,and limits its application in actual industrial process.In order to solve the above problems,a design scheme of ERT system with remote high-speed transmission is put forward,and Field Programmable Gate Array(FPGA)is used as main control chip to achieve the system scheme.The thesis includes four parts:(1)Aiming at the remote visualization measurement of multiphase flow,to make the ERT system more suitable in industrial application,an ERT system whose field unit and main control unit are connected in different location is designed.The scheme of field unit,main control unit and transmission is respectively established.(2)Aiming at the remote high-speed transmission requirement of the system,the fiber optic transmission circuit is designed based on the high-speed serial transceiver integrated in FPGA.Through designing the high-speed transmission protocol logic based on AXI4-stream Aurora,remote and high-speed data interconnection of the system is realized.(3)The Exciting-Acquisition circuit of field unit and the CPCI interface circuit of main control unit is designed on the basis of the system scheme,combining the fiber optic transmission circuit,the hardware structure of field unit and main control unit module is finished.Through the logic modules as chip control,digital signal processing,asynchronous cache and CPCI control are designed in FPGA of the field and main control unit,the function of the system is realized.(4)Set up an experimental test platform based on field unit and main control unit module,after the verification of high-speed remote communication function of the system,calibration experiment is carried on and the system performance parameters are analyzed.Through the image reconstruction test experiment by placing simulator object in testing sensor,the feasibility of the system is verified.