Technology temperature compensation technology of the methane sensor with tunable semiconductor laser spectrum absorption

With the development of gas detection technology with tunable semiconductor laser absorption spectrum, the sensor based on this technology is the current focusing area for coal mine methane monitor study. Now the sensor has already used in coal mine, but the influence of ambient temperature to measurement accuracy is large. To overcome this problem, an adaptive iterative compensation algorithm was proposed which is a piecewise interpolation fused with the Lagrange barycentric interpolation. Firstly, the influence rate of measurement temperature was calculated based on the sensor calibration value. Secondly, the barycentric interpolation function was calculated under different temperatures. Then the new influence rate of measurement temperature was calculated to measure the methane concentration values. The authors got the compensation methane value by this new rate of temperature affect, according to the implementation of adaptive iteration. A lot of tests show that the measurement error is reduced to 1% in the high concentration gas conditions, the measurement error is reduced to 0.01% in the low concentration gas conditions. The engineering applications show that the measurement error decreases significantly. This method provides a reliable guarantee for the laser sensor used in coal mine. ©, 2015, China Coal Society. All right reserved.