Study On Reliability Of Distributed Temperature Sensing System

Distributed temperature sensing (DTS) system, integrated with sensing measurement technology, optical communication and fire alarming technology, is a new kind of temperature sensor with advanced measurement technology. Due to its advantages of distributed real-time measurement, precise location, high sensitivity, wide dynamic range, and immunity to electronic magnetic interfere in tremendous applications, it was widely used in the field of power industry, petroleum chemical industry, and metallurgical industry etc. As a result, it attracts more and more attention both at home and abroad.Nowadays, compare with the similar foregin products, the domestic DTS system have a close function but a much lower reliability. Therefore, the foreign DTS products could cost up to 1.5-2 times as much as the similar domestic products. Manufacturers such as Seimens and Angilent take up the higher-end market of China, while our national manufactures stay in the lower-end market. How to improve the reliability of the domestic DTS system became an urgent problem for national manufactures to solve. In this paper, the reliability of DTS system has been investigated. The thesis mainly includes the following contents:1. The background and the significance of the topicThe advantages and applications of DTS system were briefly introduced. The current situation as well as the history of DTS system's reliability was presented. On the basis, the methods of how to study the reliabity of DTS were proposed.2. Establish the work flow of DTS system reliabilityAccording to the theory related with reliability and the characteristics of DTS system, combining the reliability requirements of DTS system, work flow of DTS system reliability was established in order to guide the research.3. Summarize the effect of performance improvement on the reliability of DTS systemThe reliability design of DTS system was analyzed, and the relationship between the key technical indexes was presented. Based on this, the effect of performance improvement on the reliability of DTS system was summarized.4. Propose a new method of threshold variation to improve the reliabilityThe applications of wavelet transform in signal denoising were briefly discussed according to wavelet theory. The disadvantage of traditional DJ threshold method was pointed out. Based on the temperature inversional curve of the DTS system, the noise model was refined, thus, a new method of threshold variation was proposed to improve the reliability.5. Independent design of the key optical components testing equipment and finish the experimentTake the design of DTS system as an example, based on the requirements of DTS reliability, the key optical components testing equipments were independently designed under the guidline of the research work flow. Referred to the series of General Requirement standards and the related national standards, system tests were carried on, included optical module testing, the system testing, reliability experiments and Beta testing. The defects of the system were located according to the testing results, then the reasons were analyzed and measures were taken to revise the defects. As a result, both the peformance and the relialbity of the products were improved.