输电线断线振荡研究

针对采用拟静力法不能计算输电线路断线动态张力的缺点,利用显式动力有限元方法研究了输电系统线路断线的振荡响应。研究表明:在邻近断线档绝缘串下端的动、静位移以及不平衡力响应较大,远离断线档迅速衰减;线路的动态张力峰值是初张力的1.5倍―2.5倍,且离断线档越远,放大作用越大;线路的静态张力是初张力的0.26倍―0.95倍,且离断线档越远,卸载作用越小。该文还研究了初张力、档距和绝缘串长度对断线响应的影响。

STUDY ON WIRE BREAKING-INDUCED VIBRATIONS OF ELECTRIC TRANSMISSION LINE

The vibration caused by broken wire can be calculated with pseudo-static method, but dynamic longitudinal tension responses can not be calculated by this means. To avoid this disadvantage, explicit dynamic finite element method was presented. Results indicate that the displacement as well as non-balanced load responses from broken lines are larger at bottom of insulator string which approaches broken-line span, and responses weaken rapidly with the distance increasing from broken-point. The peak of dynamic tension response is 1.5―2.5 times of the initial tension and the amplified factor is growing with the distance increasing. The static tension response is 0.26―0.95 times of initial tension. The unloading function is dropping with the distance increasing from broken-point. In addition, the influence of some parameters on transmission line system responses, such as initial tension of wire, span between two neighbor towers, length of insulator string have also been investigated.