Study On Key Technology Of Distributed Fiber Optical Temperature Sensor System

Since the invention of distributed fiber optic temperature sensor based on Raman in the 1970s, It developed and diffused in a egregious speed .Its excellent capability, mightiness function and tremendous application foreground attracted a great number of experts to work over it, promote this technique to its ripeness. Raman dispersion theory, the foundation of distributed fiber optic temperature sensor is a ripe theory. It is not difficult to research the principle of sensor system, it only took the research group led by the author 1 year to develop the principium showpiece in the early 1990s. But elementary overcoming the problem of stability of the system took the research group 3 years, It is more hard to study its practical usage. This paper is a summary of the author's longtime research of the distributed fiber optic temperature sensor system. In the paper, the author introduced the background knowledge and principal of distributed fiber optic temperature sensor technique. The author found out the relation of two-way Raman signal voltage and temperature, corrected a conception error of the craft brother. The result is similar to the formula of GESO Corp German, but more exactness, especially its evident advantage in the precision of the fiber on the other side which has a important supervising meaning in the correct use of distributed fiber optic temperature sensor technique. Starting from the Physics Optics, based on the formula of interference filter in declining state, the author brought out the method of matching filtering which can greatly improve the effect of filter. It took on important worth of application. This paper particularly analyzed the factors which affect the stability of the system , especially the temperature shift of APD. The paper brought forward and excogitate a technique of dynamic compensating with which can greatly enhance the adaptive capability of temperature of the APD. In the research of usage, with the help of Ningbo Zhengdong photoelectricity CO. LTD., the author carried out a research of the usage in the cosmically dam leakage supervising ,brought forward mode of active exciting and successfully used in leakage supervising of a water electricity station stand in Guangdong province. Using the method, the author tested out the leakage area of the new-built dam and approximately the quantity of leakage .The result has afforded useful information of the water electricity station's running and maintenance. In the field of pipeline leakage supervising, the paper first brought out a leakage supervising method based on joule-Thomson effect and then analyzed the relation of leakage matter ,leakage part and the way optical fiber was laid. In the paper the author amply introduced the arts and crafts of optical cable construction. In the field of cable temperature supervising, the paper introduced the application sample of Qingshan nuclear power station. In this application, the author checked out one of the three tie-in used in cooling water power cable's quality problem. This offered efficacious supervising means to insure the nuclear reactor to run steady...