Numerical Simulation Analysis On Operating Temperature And Current Carrying Capacity Of Overhead Conductor

In recent years,in order to meet the increasing demand for electricity,dynamic increasing capacity technology has also been more and more extensive research and application,However,the long-term high temperature working conditions of the wire are gradually becoming a factor that can't be neglected in the safety and reliability of the line operation.At present,the existing dynamic increasing capacity technology,mainly focused on wireless communication technology in the real-time monitoring applications of conductor surface temperature,the research which the the reason and distribution of the working temperature field of the conductor itself and the influencing factors(wind speed,wind direction,ambient temperature,sunshine intensity,etc.)is relatively inadequate.And these have an important effect on the accurately determining the temperature and the current carrying capacity of the conductor,so it is worthy of further study.Based on this,in this paper,LGJ300 / 50,for example,to study its wind speed,wind direction,ambient temperature,sunshine intensity under the influence of the temperature distribution law,so as to provide the theoretical support for the dynamic increasing capacity technology of the transmission line and also provide reference for the material and fatigue analysis of the conductor under working conditions later.The main contents and conclusions of this paper are as follows:(1)Taking the IEEE standard as an example,the heat balance equation of the conductor and the calculation method of convective heat dissipation,radiation heat dissipation,sunshine heat generation and resistance are introduced in detail,which provides a reliable basis for the finite element numerical simulation;(2)Homogeneous conductor model which not considering the air clearance is established by using ANSYS software,verify the accuracy of ANSYS simulation method and definite the wind speed,wind direction,environment temperature,sunshine intensity and so on the influence law of temperature change for conductor as a whole,provide reliable support for the subsequent analysis;(3)Fine line model which considered the influence of the air gap on the heat conduction and the actual contact between the conductors is established by use of ANSYS software,the accuracy of the radial temperature distribution of the conductor is verified;The results show that the radial temperature difference of the conductor varies from 4? to 10 ? with the change of wind speed,wind angle,ambient temperature and sunshine intensity within the scope of the carrying capacity in 410 A ~ 860 A,the influence of the temperature difference on the current carrying capacity is 70 A ~ 80A;The existing temperature monitoring device,the measured wire temperature is the surface temperature of the wire,in order to adjust the transmission capacity of the line is biased unsafe,combined with the existing real-time capacity increasing technology,the temperature field of the wire under the corresponding environmental conditions can be analyzed by ANSYS;Based on the temperature distribution of the points in the conductor,the allowable current carrying capacity of the most unfavorable position is calculated and improving the line transmission capacity on the basis of ensuring the safe operation of the line;(4)Combined with the results of analysis of temperature field and the IEEE standard,the capacity of overhead conductors were analyzed.The results show that the influence of wind speed,wind direction angle,ambient temperature and sunshine intensity on the current carrying capacity of the conductor is from large to small.Finally,the influence of the radial temperature difference of the wire on the stress analysis of the wire and the influence of the temperature heat affected zone on the temperature field analysis of the multi-split wire are put forward,and the prospect of the follow-up work is put forward.