Research On Process And Prediction Model Of Icing On Transmission Lines

A large number of facts and records indicate that ice on overhead transmission lines seriously jeopardizes the safety of power grid operation.All kinds of electrical and mechanical accidents caused by ice coating not only affect the normal operation of the power grid and the user's electricity consumpcovered mechanism and prediction model of transmission lines can make important contributions tion,but also bring huge economic losses and safety hazards.The research on the ice-to the design of transmission lines,forecasting and warning of ice coating,and timely measures to prevent freezing and deicing.However,the current research on the formation process of ice-covered lines and the establishment of prediction models is not perfect,and the calculation accuracy of prediction models needs to be improved.These are the problems that need to be solved urgently.This paper aims to systematically study the ice-covered process and prediction model of transmission lines in view of the key problems existing in the research of ice-crack prediction in existing transmission lines.The main work and achievements of the thesis are:(1)Based on fluid mechanics,the governing equations of air and supercooled water droplets are established.The calculation method of collision coefficient is proposed.The influence of gravity on the collision coefficient is studied.The influence of gravity on the calculation of collision coefficient is determined.conditions of;(2)Based on the heat transfer theory,the existing ice surface heat balance equation of the wire surface is improved.By considering the effects of current Joule heat,wire surface temperature and collision coefficient on the freezing coefficient,an improved calculation method of the freezing coefficient is proposed.The improved calculation results are compared with the original calculations;(3)Based on the above calculations,the prediction model of transmission line ice coating is established.The correctness of the model calculation is verified by experimental results,and the ice quality and shape are analyzed separately.