Design Of Main Control System For Circumferential Borehole Ultrasonic Imaging Tool

Since mankind entered the industrial society,petroleum has played an irreplaceable role in social development and has become the "blood" of the industrial society.Petroleum is generally deep in the stratum,thus various technologies are needed to detect and excavate it.Improving the accuracy and efficiency of petroleum exploration and developing high-level logging tool are of great significance for exploring new oilfields,increasing the amount of petroleum extracted,and even ensuring the development of the country.In the field of petroleum logging,CBIL(circumferential borehole imaging logging)is an important branch.CBIL can intuitively reflect the situation of petroleum wells with well wall images,and can clearly see the development of cracks and holes on the well wall.It is an important method for petroleum well evaluation.The well logging methods mainly used in the field of CBIL include ultrasonic imaging and micro-resistivity scanning.Ultrasonic imaging method has the advantages of high resolution and intuitive imaging,it can also carry more information.In this thesis,the hardware circuit design and software program design of the main control system for CBUIT(circumferential borehole ultrasonic imaging tool)is mainly discussed.First of all,the development and research status of the field of CBIL at home and abroad are summarized,and the structure of the tool is analyzed to clarify the working principle of the tool.Secondly,from the functional requirements of the tool,the overall structure design of the main control system of the CBUIT is described and the working process of the tool is analyzed in the thesis.Then from the view of hardware and software design of the tool’s main control system,the specific design scheme is described and the working principle and function of each module are clarified.According to the functional requirements of the main control system of the CBUIT,the core of the hardware design is PIC(Peripheral Interface Controller)and FPGA(Field Programmable Gate Array).PIC is responsible for decoding various commands of ground system,collecting auxiliary information,synchronous control of collecting.FPGA is responsible for specific process control of fire and collecting,storage,processing and upload of collected data.The hardware circuit of the tool also includes power module,auxiliary information measurement module,EDIB communication module and acquisition synchronous signal shaping module.In the software module,the communication program design of the main control system,the synchronous program design of the fire acquisition process,the program design of storage and processing of collected data,the algorithm design of amplitude and arrival time extraction,and the program design of auxiliary information measurement are described.In the end of this thesis,each functional module of the main control system is tested separately,and the experimental environment,process and results are described in detail.The experiment results are analyzed and they show that the main control system of well circumferential ultrasonic imager meets the design requirements and lays a certain foundation for the development of CBUIT whole equipment.