Research On The Characteristics Of Double Capacity Conductor And Engineering Application Of New Lines

With the great increase of power load and decreased power transmission corridors,there are more and more pressing demands for improving the transmission power of corridor.Under the background,domestic and foreign companies have developed s series of double capacity conductors.Based on learning about the development history,production process and electronic and mechanical speciality of double capacity conductors,the paper has studied arc sag,carrying capacity,width of corridor and other technical problems specially and applied them to engineering with the major contributions as follows:(1)This paper proposed a calculation method of arc sag of double capacity conductor and verified it.When the tension of wire at migration point completely migrates to core of wire,wire is equivalent to a wire completely consisting of core of wire and migration point and other stress methods are applied to the calculation of arc sag of double capacity conductor.Based on the above principle,the paper deformed,innovated and recycled catenary equation of line strung to make it suitable for the calculation of arc sag of double capacity conductor.The methods in the paper are applied to the design of newly-built power transmission line.After being put into operation,on-site measurement of relaxation degree of arc sag verifies the correctness of these methods.(2)High-voltage power corridor is an important factor influencing the construction of transmission line.The paper explored the applicability of double capacity conductor in urban regions or dense regions through calculation and combining the occupation of electric power corridor by double capacity conductor.The conclusion is: when double capacity conductor and normal conductor with same sectional area have the same working current,carbon fiber occupies the least corridor followed by ACCR,and the other two double capacity conductors occupy the basically same corridor as normal conductors.When the working current of double capacity conductor is twice that of normal conductors,carbon fiber occupies the least corridor and the other three double capacity conductor occupies more power corridors than normal conductors,which is different from the existing research results.The final suggestion is to adopt carbon fiber conductor in urban areas or dense regions.(3)The paper applied of double capacity conductor in a newly-built transmission line project.It is concluded by comprehensively comparing the technical economy of four kinds of double capacity conductors and traditional aluminum cable steel reinforced that when the control tension is same,ACCC has the longest electrical distance to ground and spanned electrical distance and best sag characteristic followed by ACCR.ACCR has the most total investment of project followed by normal conductors and GTACSR and;after being put into operation;normal conductor has the highest rate of return on investment and best economy followed by GTACSR and double capacity conductor.In addition,the paper summarized the practical problems and their solutions in design and construction and obtained the applied range and notes for double capacity conductor in newly-built conductors.