摘要
重覆冰区线路覆冰后不均匀脱冰产生不平衡张力,严重时可发生倒塔事故,为此在设计中计算不平衡张力,合理确定重覆冰区杆塔荷载具有重要意义。以浙北—福州1 000 kV交流线路工程为依托,分析特高压线路不均匀脱冰过程,采用等线长法计算模型,引入"扫描二分法"改进迭代算法,开发设计软件以实现对不均匀脱冰产生不平衡张力的高效精确计算。通过计算,对影响不平衡张力的绝缘子串长、导线型式、档距配置、高差、脱冰率等因素进行敏感性分析,验证计算结果并发现抑制重覆冰区不均匀脱冰的方法,从而减小不平衡张力,合理设计线路在重覆冰区的杆塔荷载,增强线路抗冰能力。对于不均匀脱冰影响很大的孤立档,建议考虑不均匀脱冰模式下的不平衡张力,加强耐张塔设计。
In heavy icing areas, the unbalanced tension of uneven ice-shedding for transmission line may cause tower failures in serious conditions. Thus calculating unbalanced tension and determining tower loads appropriately in heavy icing areas are very important. Based on Zhebei-Fuzhou 1 000 kV AC transmission line, the process of uneven ice-shedding in UHV transmission line was analyzed; by using equal line length calculation model and ＇ scanning-dichotomy＇ improved iterative algorithm, the design software was developed to realize the effective and accurate calculation of unbalanced tension in uneven ice-shedding. The sensitivities of the influence factors including suspension strings length, conductor types, different multi-span configurations, elevation difference and ice-shedding percentage were analyzed by the calculation. The calculation results were tested, and the methods of restraining uneven ice-shedding in heavy icing areas were obtained to reduce unbalanced tension, appropriately determine tower loads, and enhance anti-icing ability. For isolated span affected greatly by uneven ice-shedding, unbalanced tension mode should be considered to strengthen tension tower design.
出处
《电力建设》
2014年第10期52-57,共6页
Electric Power Construction
关键词
重覆冰区
不均匀脱冰
不平衡张力
杆塔荷载
抗冰
heavy icing areas
uneven ice-shedding
unbalanced tension
tower load
anti-ice
