基于IHB法分裂导线次档距振荡的极限环特性
Limit Cycle Oscillation of Subspan Oscillation for Two Bundled-Conductors by Using Incremental Harmonic Balance Method

分裂导线中的背风子导线在尾流激振作用下会出现大幅的次档距振荡，是威胁高压输电线路安全运行的重要故障之一。针对此问题，首先，给出了背风子导线在尾流激振下，含气动非线性的两自由度次档距振荡动力学模型方程；其次，采用增量谐波平衡法推导了求解次档距振荡高阶极限环响应的方程，得到了次档距振荡极限环响应的前三次谐波响应，结果表明，导线次档距振荡只存在于一个风速区间范围内，随谐波次数的增加，高次谐波的影响明显减弱，其中一次谐波能够较好地吻合Runge-Kutta数值计算结果；最后，分析了档距和背风子导线的初始位置对次档距振荡的影响，为避免或抑制次档距振荡的发生提供技术支持。
Subspan oscillation on bundled conductors is one of the most important failures of overhead transmission lines, which is due to the leeward conductor lying in the wake of the windward conductor. In this paper, considering the aerodynamic nonlinearities, a 2-DOF subspan oscillation dynamic model of the leeward conductor lying in the wake of the windward conductor is given firstly. And then, the incremental harmonic balance method (IHB) is used to derive high-order limit cycle oscillation of subspan oscillation system, and the first to the third harmonic responses of the limit cycle oscillation are obtained. Results show that subspan oscillation only exists in a certain range of wind velocity. Moreover, the higher order of the harmonic the weaker impact it is, and the first harmonic response agree with numerical results of Runge-Kutta well. Lastly, the influence of span and original position of the leeward conductor on subspan oscillations has been analyzed, which can provide the technical support for suppression or prevention subspan oscillation.