【摘要】 为了明确超/特高压同塔多回输电线路的覆冰动态特性,采用有限元方法分析了其脱冰跳跃动态响应。考虑几何非线性的影响,采用有限元理论建立了导/地线-绝缘子及铁塔-导/地线-绝缘子体系的脱冰跳跃精细化数值分析模型。以1 000 kV交流双回、500 kV交流双回同塔多回输电线路和±800 kV直流单回、500 kV交流双回同塔多回输电线路为例,考虑塔线耦合效应、脱冰位置、档距和高差等影响因素,完成了不同工况下系统的脱冰跳跃分析。结果表明:当铁塔较高时,塔线耦合作用对导线脱冰跳跃纵向不平衡张力的影响不大,对地线脱冰跳跃纵向不平衡张力的影响较大;边档脱冰产生的纵向不平衡张力明显大于中档脱冰。最后,对导/地线脱冰跳跃纵向不平衡张力百分比取值进行了如下建议:1 000 kV导线及±800 kV导线取10%;500 kV导线取20%;地线取100%。更多还原

【Abstract】 To make the dynamic characteristics of ice-covered EHV/UHV multi-circuit transmission lines on the same tower clear,the dynamic response of ice shedding-caused drastic conductor vibration was analyzed by finite element method(FEM).Correspondingly,considerting the influence of geometrical nonlinearity and taking the double circuit 1 000 kV transmission line and double circuit 500 kV transmission line on the same tower as well as single circuit ±800 kV DC transmission line and double circuit 500 kV transmission line on the same tower for examples,refined numerical analysis models of ice shedding-caused vibration for conductor(overhead groundwire)-insulator system and tower-conductor(overhead groundwire)-insulator system were built by FEM,in which the factors such as coupling effect of tower with lines,the position of ice-shedding,span and height diffferences were taking into account,and the analysis on the systems under various operating conditions were completed.Analysis results showed that when the tower height was higher,the longitudinal unbalanced tension of conductor vibration caused by ice-shedding was slightly influenced by the coupling effect of tower with lines,however,the longitudinal unbalanced tension of ice shedding-caused overhead groundwire vibration was influenced obviously;the ice shedding-caused longitudinal unbalanced tensions of the spans at both ends of transmission line were evidently higher than those of spans in the middel of transmisson line.Based on analysis results,it was suggested that the percentages of longitudinal unbalanced tension of ice shedding-caused vibration of conductor/overhead groundwire in different voltage classes should taken as following: for 1 000 kV and ±800 kV conductors,the percentage should be taken as 10%;for 500 kV transmission line,the percentage should be taken as 20%;and for overhead groundwire the percentage should be taken as 100%.更多还原