基于温度滞后相位的输电线路覆冰监测方法

为了获得在更加符合实际情况的环境温度下的光纤复合相线温度变化特征和覆冰与否的判据及覆冰厚度预测方法,本文建立了环境温度呈正弦函数变化情况下的光纤复合相线覆冰的温度场三维模型,并采用了有限元方法进行求解。文中分析了导线覆冰段与未覆冰段温度变化的幅值和滞后相位特征；研究了滞后相位与环境温度波动幅值、滞后相位与覆冰厚度的关系,指出环境温度波动幅值对滞后相位的影响可以忽略,获得了滞后相位与覆冰厚度的关系；提出了基于滞后相位特征的线路覆冰判据,并给出了基于滞后相位的覆冰厚度预测公式。最后建模分析获得了4种非正弦函数形式的环境温度变化下光纤温度的变化情况,基于此分析了覆冰厚度的预测公式误差,结果验证所提出基于滞后相位的覆冰判据和覆冰厚度预测公式的有效性。关键词：输电线路；覆冰厚度预测；光纤传感；温度场；正弦时变温度；滞后相位中图分类号：TM755

Icing monitoring method of transmission lines based on temperature lagging phase

In order to obtain temperature variation characteristics of the optical phase conductor under the more realistic ambient temperature, the criteria of whether the transmission line is ice covered or not and ice thickness prediction method, a 3D model of the optical phase conductor ice cover temperature field under the condition of ambient temperature into sine function change is established, and the finite elements method is used to solve it. In this paper, the variation and lagging phase characteristics of the temperature of the ice cover part and the uncoated part of the transmission line are analyzed, the relationship between the lagging phase and the fluctuating ambient temperature amplitude, the lagging phase and the ice cover thickness are studied, the effect of the fluctuating ambient temperature amplitude on the lagging phase can be ignored, the relationship between the lagging phase and the ice cover thickness is obtained, the ice cover determination of the transmission line based on the lagging phase feature is proposed, and the prediction formula of the ice cover thickness based on the lagging phase is given. Finally, four kinds of variations of fiber temperature under the change of ambient temperature in 4 non-sine function forms were analyzed and obtained by modeling, and the error of the prediction formula of ice thickness is analyzed based on this. The results verify the validity of the proposed icing criterion and the predic-tion formula of ice thickness based on lagging phase. Keywords: Transmission lines; prediction of ice thickness; fiber sensing; temperature field; the time changing temperature in the sine form; lagging phase