基于红外测温的柜内元件热故障的反问题识别

结合红外辐射理论分别建立了控制柜内部单个和多个元件同时过热时对壳体内表面的红外辐射模型,得到了壳体内表面总的热流密度分布,并针对受热壳体建立二维热传导模型。基于对壳体表面红外成像测温,运用L-M算法进行了导热反问题模拟研究,对控制柜内部单个和多个元件的发热温度和方位进行了识别,最后分析了测量误差对计算结果的影响。结果发现运用L-M算法对单个和多个故障元件的发热温度和方位进行分开反演求解和同时进行反演计算时,都取得了较好效果,求解精度较高。测量误差对发热温度的反演计算结果影响更大。

Inverse heat conduction problem identification of fault components in the electrical cabinet based on infrared temperature measurement

According to the infrared radiation theory,thermal radiation model of the inner surface of the cabinet is established.The radiation results from the overheating of single or multiple components in the control cabinet.And total heat flux distribution of the inner surface of the casing is obtained.Then,a two-dimension heat transfer model of the heated casing is developed.An inverse heat conduction problem is studied by the Levenberg-Marquardt method based on the infrared imaging temperature measurement on the surface of the casing.And the temperature and the position of the overheating components in the control cabinet are identified together.Finally,the effects of measurement errors on computational results are analyzed.The results show that the L-M method is very suitable to estimate the temperature and the horizontal distance of single overheating component.And it is also very suitable to estimate the temperature and the position of two overheating components together.The effect of measurement errors on the temperature estimating of the overheating component is large.