The Research On The Ground System Of Natural Gamma-ray Spectrometry Logging Tool

At present, there are too many types of the oil well logging instrument at home andabroad, and also different communication modes between ground system and eachmeasurement module. At the same time, foreign logging instrument is updated quickly, andmany down hole instruments are equipped with independent ground control systemrespectively, this phenomenon of weak compatibility is so common. In addition, the traditionalnatural gamma-ray spectrometry logging tool has low rate in bus transfer and it is also haslarge power consumption, and so forth. In order to meet so much request, we put forward ahigh-speed cable telemetry system between the ground system and all kinds of down holeinstrument to realizes the function of large amounts of data transmit real-time and accurately.And make a further research in high efficiency and high reliability bus technology. Therefore,to develop a new stale and strong expansibility of the natural gamma-ray spectrometry loggingtool ground system is particularly important.At first, this article is start from the background of the oil well logging instrument,introduces the working principle of gamma-ray logging tool briefly, the concept of naturalgamma ray spectrum logging ground system and the development of ground system at homeand abroad at present. Combined with DSP control technology and multiple bus interfaces, Itis applied to the ground system study, so as to put forward the research direction in this paper.At second, the paper introduced the development of DSP technology, the chip’s basicstructure and it is summarized the characteristics of the chip TMS230LF2407. In order tocontrol the ground system, the research focus on the TMS320LF2407chip which has manybus interfaces module init. At the same time, this paper also expound that the controllerfeatures, internal function and features of the related peripheral circuit on chipTMS320LF2407.At third, we put forward the design scheme of the ground system hardware circuit. Wedesign the hardware circuit through DSP microcontroller, which is including the telemetrysystem module, the signal processing system module and the depth system of modular. At thesame time, the design involve the design of the hard core control which is based on DSP and CPLD technology, the front signal processing system and the bus interface driver circuit,etc.The result of preliminary debugging experiments showed that the natural gamma loggingground system can realize communication with down whole instrument, through variety of bustransmitted data with PC, connected the data collection and transmission nodes to the groundCAN network, which is complete the command of sending and data upload by groundpretreatment equipment.