SF_6局部放电分解组分光声光谱检测的温度特性

Temperature Property of Photoacoustic Spectroscopy Detection for SF_6 Decomposition Components Under Partial Discharge

光声光谱检测法在SF6局部放电分解特征气体组分的检测中有较好的效果,但检测温度对其检测的准确度有较大影响。为此,利用构建的光声检测实验平台,获取了SO2、CO2和CF4这3种单一特征气体组分的光声信号温度特性和混合特征气体组分的红外交叉响应特性,对温度影响气体光声信号检测准确度的原理进行了理论分析。研究发现,在30～50°C温度范围内,SO2(波长为7.35μm)、CO2(波长为4.26μm)和CF4(波长为7.78μm)的光声信号值具有负温度特性,混合特征气体组分的交叉响应比例具有正温度特性。同时,提出了一种光声检测微量气体的温度线性校正模型。对该模型进行了校正检验,校正结果与参考温度下的标准光声信号误差<4%。该模型为SF6局部放电分解特征气体组分的光声光谱检测和相应在线监测装置的研制奠定了可行的温度校正基础。

Photoacoustic（PA）spectroscopy performs well in the detection of SF6decomposition components under partial discharge（PD）,but the testing temperature has a major influence to its accuracy.To investigate how temperature affects the accuracy of the PA signal gas detection,we got the PA signal temperature properties of SO2,CO2,and CF4separately and the cross response properties of the gases＇mixture after constructing a PA experimental platform.Based on the experimental results,the effect of temperature on the detection was theoretically analyzed.The experiments show that the PA signal of SO2,CO2,and CF4have a negative temperature property but the cross response ratios of mixed gas has a positive temperature property in range of 30～50°C.Moreover,we put forward a temperature linear correction model which can be used in PA detection of trace gases.The model was regulated,and the corrected result has error less than 4%to the standard PA signal under reference temperature.The model could be used as a feasible temperature correction foundation for PA detection of SF6 decomposition components under partial discharge and corresponding on-line monitoring devices.