Design Of Logging Data Acquisition And Transmission System Based On CAN Bus

At present, the comprehensive logging instruments are playing more and more important roles in oil industry. The instruments being used in oilfield are low-precision, and not able to monitor the drilling parameters accurately. Data acquisition signals are communicated with RS485 bus point to point. As a result, installation and disassembly of instruments become heavy loads, and instruments may be damaged easily. To overcome these disadvantages, this thesis develops comprehensive logging instruments and applies CAN bus technology into instruments. CAN bus has excellent real time capability and stability. The instruments have such function as data acquisition, real-time data transmission and monitoring real-time data.Micro Controller Unit technology and CAN bus communication technology are applied into the design of comprehensive logging instruments, PCI1680 CAN bus communication card brings the Control Area Network to upper computer,to meet the needs of logging data acquisition and transmission. The software and hardware of data acquisition modules and CAN bus communication module are developed. The CAN bus communication control procedures of upper computer is completed. Anti-jamming measures are designed. Finally the function of integrative logging instruments is realized.The instruments have been tested in lab, and field experiments have been carried out. The experiments results show that this design is able to implement analog signals data acquisition at high accuracy, measuring periods of pump stroke signal and realizing winch signal processing. Meanwhile the CAN bus communication module is put into instruments, which improves data transmission communication rate and overcome such disadvantages as heavier loads of installation and inconvenience of operation. The instruments have a broad application prospect.