云广±800kV直流输电重冰区导线选型

Conductor Select for Yun-Guang ±800kV DC Transmission Line in Heavy Ice Area

为了合理地选择云广±800kV直流输电工程重冰区的导线型号,采用CISPR的无线电干扰预估公式、美国BPA与EPRI的可听噪声预估公式预估了不同型号导线的电磁环境参数,分析极导线不同分裂根数时的无线电干扰、可听噪声、导线振荡、次档距振荡、覆冰跳跃以及覆冰舞动等后确定了极导线的分裂根数与分裂间距;计算、比较了不同型式导线的单丝性能、外层单丝应力、覆冰过载能力、弧垂特性等因素对杆塔荷载的影响;在采用年费用最小法比较不同导线组合,并评价整个工程供电安全性后推荐云广±800kV工程20mm重冰区采用普通钢芯铝绞线6×LGJ-630/45,30mm重冰区采用钢芯铝合金导线6×LJHA1/G3A-630-54/19。

The proportion of conductor cost for UHV transmission line project will be generally more than 30%, and the size of conductor affect highly the cost of tower and foundation. For heavy ice area, there are usually high altitude, tanglesome terrain, severe weather and bad traffic condition, the conductor choose should satisfy running safely and reliably, hence the choice of conductor type is one of very important topic for studying. The authors analyze the characteristics of multi-bundled polar conductor for ±800 kV UHV DC transmission line, including radio interference, TV interference, audible noise, total electric field, ion current density, magnetic field and static induction ete electromagnetic and environmental influence. As well as conductor oscillation, conductor jumping etc caused by heavy ice or ice dropping. Thereby, decide the sub-conductor numbers and sub-conductor spacing of polar conductor. And then through the comparison of different kinds of conductors characteristics such as the performanee of single thread of wire, stresses of outer single thread, ability of ice overload, sag property, different effect to tower load, the authors analyze and compare their security and economical factors. And finally, recommeng the ordinary aluminum conductor steel reinforced （ACSR） as the polar conductor in the 20 mm heavy ice area, and recommend the aluminum alloy conductor steel reinforced （AACSR） as the polar conductor in the 30 mm heavy ice area for the Project of Yun-Guang ±800 kV UHV DC transmission line.