Icing Thickness Measurement Of Overhead Conductors Based On Computer Vision

Icing on overhead transmission lines is one of the key factors affecting the safe and stable operation of power grid.Icing on the line will increase the load of the line,which will lead to tripping of the line,damage of fittings,even disconnection and tower collapse.Therefore,with the development of China's power grid construction,the requirements for building a strong smart grid are gradually increasing.Studying the method of monitoring icing thickness of overhead transmission lines is of great significance to realize on-line monitoring and prevention of icing in transmission overhead transmission lines,to control ice damage and to improve the reliability of grid operation.According to the relationship of overhead transmission line equivalent icing thickness and sag,establishing the mechanical calculation of overhead transmission line icing model,through the central span sag of the computer vision measurement calculation of ice thickness.The main research work has been done:(1)Based on the overhead conductor state equation of the parabola model,the mechanical model of the equivalent ice thickness is established by iterative method of continuous gear and isolated span.According to the central span of iced conductor sag,the ice thickness is calculated by iterative central span sag,the difference between calculated and actual central span sag by computer vision measuring sag as the objective function calculation of ice thickness.For the above algorithm,the MATLAB iterative method is developed to calculate the ice thickness of continuous gear,and compared with the actual data,it is proved that the iterative algorithm has good convergence.(2)Monocular computer vision measuring principle the central span of overhead conductor sag are analyzed based on monocular computer vision principle,in order to make the sag measurement more accurate at the same time,the nonlinear distortion of non wide-angle lens is calculated and analyzed under laboratory conditions,the experimental results show that non wide-angle lens have small nonlinear distortion of camera,and can be ignored in this measurement.Then,the matching accuracy and speed of different image matching algorithms are analyzed and compared.Finally,the normalized matching algorithm is used to identify the target to measure the sag of overhead wires.(3)According to the principle of equivalent ice icing,set up a centralized mass model for simulated continuous overhead conductor icing in the outdoor,and the ice thickness is calculated by using the ice thickness calculation model established in this paper.Finally,the model established in this paper carries on error analysis by comparing with the real equivalent ice thickness.