【作者】 张健；

【导师】 娄晖；

【作者基本信息】 中国石油大学（华东） ， 机械工程， 2013， 硕士

【摘要】 井下温度、压力等参数信息的实时监测对认识油气储层特性、了解油藏的开发动态、分析地层的油气储藏量和分布、评价生产状况和油气井的寿命具有极其重要的意义。而实现井下温度、压力参数实时监测的关键在于实现井下与地面之间信息的可靠传输。本文所研究的无线电磁短传系统将信号的井下短距离无线传输技术与电缆地面直读技术结合起来，能够实现生产井关井状态下关井工具下部井筒温度压力信息的实时监测，可以有效提高测量精度和信号传输稳定性，技术与经济意义显著。本文首先利用有限元分析软件Ansys分析传输距离、油套管管径、环空间隙、壁厚及环空液体矿化度对系统传输特性的影响规律，根据分析结果确定了无线电磁短传装置机械结构参数的选择依据。其次在地面模拟实验平台基础上，完成信号传输幅频特性实验，找出了信号传输稳定、衰减程度较小的频率范围，并确定了信号衰减倍数，为电路系统的设计提供数据支持。基于地面实验结果，分别设计信号发射器、信号接收器和电缆直读系统。信号发射器作用为对温度压力等信息进行采集并转换为不同频率正弦波的输出，正弦波信号经放大之后驱动发射线圈，本文分别基于ICL8038和单片机实现了信号发射器的设计；信号接收器作用为将接收线圈检测到的小信号进行放大并转换为方波，通过单片机脉冲计数功能获得信号的频率信息；电缆直读系统是通过CAN通信实现两个微控制器之间的远程通信，用以模拟信号从井下到地面的远程电缆传输过程。在完成电路系统设计的基础上，根据电路设计方案绘制出PCB板；完成井下供电电源和传感器的选型；结合有限元分析所得规律设计出承载磁芯线圈、电路板、供电电源和传感器的发射短节、接收短节，最终实现了无线电磁短传系统的整体方案设计。更多还原

【Abstract】 The real-time monitoring of down-hole temperature and pressure parameters is of greatsignificance to realize the reservoir characteristics and understand the reservoir developmentperformance. It is also of great importance to analyze the oil and gas reserves and theirdistribution, to evaluate the production statement and oil well age-size. The key to achieve thereal-time monitoring of down-hole temperature and pressure lies in the reliable informationtransmission between bottom hole and ground surface. The down-hole data wirelesselectromagnetic transmission system studied in this thesis is a combination of down-hole datashort distance wireless transmission technology and electric cable based surface read-outtechnology. With the help of this system, we are able to monitor the temperature and pressureinformation of the lower part of down-hole shut-in tool under well shut-in condition. And thissystem will improve the measurement accuracy and signal transmission stability evidently,which is of remarkable technical and economic significance.In this thesis, we firstly analyze the system transmission characteristics under differenttransmission distance, different tubing and casing diameters, different annular clearance,different wall thickness and different annular medium electric resistivity with the help ofAnsys. According to the analysis results, we determine the parameter range of the down-holedevice mechanical structure.Then on the basis of ground simulation experiment platform, the voltage-frequencycharacteristic experiment is finished and the frequency band under which the signal willtransmit stably with less attenuation is found. The attenuation multiple is also known. Theexperiment results will provide data support for the design of the circuitry system.The signal generator, signal receiver and electric cable based surface read-out system are designed according to the ground experiment results. The signal generator will collect thetemperature and pressure information and transform them into sine wave with differentfrequencies. The sine wave will drive the transmitting coil after amplification. We designsignal generators separately on the basis of ICL8038and MCU. The signal receiver willamplify the small-signal detected by receiving coil and then transform the sine wave intosquare wave. The MCU will measure the frequency value of the square wave through lowpower timer function. The electric cable based read-out system will achievetelecommunication between two microcontrollers through CAN communication protocol. Theelectric cable based read-out system is used to monitor the electric cable communicationbetween bottom hole and ground surface.On the basis of circuitry system, we draw out the PCB boards according to the circuitdesign scheme. The down-hole power supply source and temperature sensor are chosen. Andcombine with the Ansys analysis results we work out the transmitting mechanical joint andreceiving mechanical joint. Their function is supporting the magnetic core coils, the circuitwafers, the down-hole power supply source and the sensor. Finally, the overall design schemeof wireless electromagnetic short transmission system was achieved.更多还原