联合NDIR技术与灰色系统OBGM(1,N)模型的高压组合电器SF6分解产物时间序列测量与预测

Time Series Measurement and Prediction of SF6 Decomposition Products of High Voltage Switch-gear Combined NDIR Technology and Grey System OBGM (1, N) Model

SOF2、SO2、H2S和CF4等分解气体是高压组合电器设备中SF6气体在故障或过热条件下的重要分解产物,其含量及时间序列变化规律可表征绝缘材料表面放电情况,且对基于气体组分分析的高压组合电器设备潜在缺陷诊断具有较好参考价值。基于此,应用非分散红外技术(non-dispersive infrared,NDIR)研制了SF6气体分解产物光学传感器检测系统,该系统采用单光源、双波长结构,有效消除不稳定因素,具有较高测量精度。在高低量程范围内分别通过线性及一阶指数分段函数拟合对该系统进行校准标定,拟合系数R2分别为0.985和0.994,一致性良好。实验结果显示:在测量浓度范围内,最大示值误差为-4.25%,随着气体浓度的增大而增大;最大相对标准偏差小于3%,表现出良好的稳定性。基于NDIR原理测量技术获取SF6分解产物体积分数时间序列,并应用灰色系统OBGM(1,N)模型对其进行拟合、预测,实现了气体体积分数高精度拟合以及广域时间域内的气体浓度预测分析。该方法为气体绝缘封闭开关设备中SF6分解气体的快速测量及预测分析提供了一种较为新颖的思路。

SOF2、SO2、H2S and CF4 gases are the important decomposition products of SF6 in the high voltage combined electrical equipment.Its content can not only characterize the surface discharge of the insulating materials,but also have great significance for the research of the potential defect diagnosis technology of high voltage combined electrical equipment based on the gas analysis.The gas sensing and detecting system of the SF6 decomposition products is developed based on the non-dispersive infrared(NDIR)technology.The system adopts the single-light source and the dual-wavelength structure,effectively eliminates the unstable factors and has the high measurement accuracy.The system was calibrated by linear and first-order exponential function fitting in the range of high and low ranges,and the fitting coefficients R2 were 0.985 and 0.994 respectively,showing good consistency.Combining NDIR principle measurement technology with grey system OBGM(1,N)model fitting and predicting technology,the gas volume fraction single-point high-precision measurement and the wide-area time interval gas concentration fitting and predicting operation can be realized.The experimental results show that the maximum error is-4.25%within the measured concentration range,which increases with gas concentration.The maximum relative standard deviation is less than 3%,showing the good stability.This system can provide the novel method for the rapid detection of SF6 decomposition products in GIS.