视频成像测井光缆传输系统井下电路设计

Design of Downhole Circuit for Well Logging System of Video Imaging Fiber-optic Cable Transmission

成像测井技术中比较有代表性的两种技术是超声成像测井技术和视频成像测井技术,其中视频成像测井技术因其图像直观、清晰、容易理解等特点,在套管井等领域有所应用。研究基于曼彻斯特编码数据传输机制,采用FPGA为主控单元和信号处理单元,利用光模块完成信号的电光转换,设计并实现了一种视频成像测井光缆传输系统井下电路。该电路结构简单、易于维护、可靠性较高,可满足井下环境的要求,与井上电路配合使用,可实现井下视频信号的实时、无压缩可靠传输。另外,该研究还为解决组合化测井带来的大数据量传输问题提供了参考。

Ultrasonic imaging logging and video imaging logging were two kinds of typical imaging logging technologies, of which video imaging logging was used for casings logging because its characters of direct, clear imaging and easy understanding, a down-hole circuit of video imaging fiber-optic cable transmission well logging system was designed and implemented. The circuit was based on the mechanism of Manchester Code Transmission Transceiver, FPGA was employed as main control and signal process unit and optical module as conversion element between electrical signal and optical signal. The circuit is simple, easy maintained with high reliability and can meet the requirement of downhole environment, it can realize video signal transmission in real-time and uncompressed transmission. Besides, it also provides a reference for huge data stream transmission of modularized logging.