过套管电阻率测井方法应用研究-控制理论与控制工程专业论文.docxVIP

Subject : Research on the application of through casing resistivity logging Specialty : Control Theory and Control Engineering Name : Ma Hui （Signature） Instructor: Huang Xiangdong （Signature） ABSTRACT The domestic through casing resistivity logging instruments are mostly imported from abroad. Besides the higher price, the maintenance and alteration of instruments and the management of accessories are controlled by human. It is imperative to have our own technology in today that science and technology is productivity. Firstly, the basic principle of through casing resistivity logging is introduced and analysed in the thesis. Based on the understanding of each part of the structure, the mathematical model of the through casing resistivity logging system is established combining with the design experience of logging instrument which is more mature, and the measurement formula of resistivity in the steel casing is calculated by the node voltage method. Secondly, aiming at the complex principle of through casing resistivity logging, and base on the analysis of the model of through casing resistivity logging system, the design proposal of system is proposed. Each weak signal of voltage acquired by this logging system, as wells each collected voltage and current are calculated in the measurement formula of resistivity logging system through the steel casing wells. The experimental results show that this method has a high accuracy of measuring data and reaches the detection requirements of the weak signal of resistivity. After the characteristic analysis of transmission mode of CAN bus, CAN bus transmission mode is applied in the system, and the speed of data transmission is improved. With the technology of over-sampling, noise-shaping and digital filtering, ??? ADC can efficiently reduce the quantization noise from output signal band, thus improve the SNR (signal to noise ratio). The modulation process and demodulation process of ?????is simul