The Development Of LNG Detector With Self-Calibration Function

Rapid development of LNG (liquefied natural gas) in recent years, its proportion of energy consuming structure is increasing. Safety is very important in LNG transport and storage. As combustible gas, LNG will cause heavy accidents when its concentration is over explosion limit, if it leaks. The LNG detector of this subject can detect LNG leakage in its transport and storage to prevent such accident.There are many methods applied to detect combustible gas, and all kinds of detecting instrument emerge in endlessly. But the traditional instruments of this kind always have some shortcomings, such as low measuring precision, poor stability, short service life etc. To solve such problems, the following studies on LNG detecting have been carried out in this subject.First, self-calibration technology has been researched to solve the problems, such as nonlinearity output, zero drift, and sensitivity attenuation of this sensor. Second, the hardware circuit has been designed. The constant temperature-controlled circuit makes catalytic combustible gas sensor work in constant temperature state. This method not only prolongs the sensor's life, but also is the basis of self-calibration technology.Third, the embedded software based on the MSP430 MCU has been designed to the implement the function of different parts.Last, function and system debugging has been taken. Experimental data were recorded for providing evidence of improved design, and the verification on the feasibility of the design.Based on research contents, this paper presents a new method for LNG detecting using catalytic combustible gas sensor. This method has been used to development a new style LNG detector with self-calibration technology. The detector has lots of advantages such as easy operation, high precision, and long life etc, so it is worth of popularization.