提高输电线路输送容量DLR系统的相关理论研究

Theoretical Research on Dynamic Line Rating System for Improving Transmission Capacity of Overhead Line

采用动态提高输电线路输送容量技术能够极大地提升我国电网输送能力,起到少建或缓建输电线路的目的。文中在复杂的有风状态下,对导线进行受力分析,在风偏平面内建立导线的张力、弧垂的力学分析计算模型。利用温度和弧垂的关系,对架空线路状态方程进行修正,得出导线的最终温度。针对目前计算导线输送容量的几种数学模型的特点和存在的问题,采用了WM和TS模型相结合的热动力学数学模型来计算线路容量,使系统能够得到最优的动态容量曲线。初步的仿真试验结果证明了该模型的有效性和实用性。最后结合DLR技术的特点和目前我国电网存在的问题,阐述了我国电网采用DLR技术的必要性及意义。

The dynamic line rating technology can be used to substantially improve the transmission capacity of overhead lines, and decrease or delay re-building transmission lines. This paper analyzed the force balance of overhead line considering wind speed and direction in a deflection plane. On this basis, a mechanics analysis model of line＇s tension and sags was established. The state equation of over-head line was corrected using the relation of temperature and sags, and the ultimate temperature of over-line was deduced. The advantages and drawbacks of some mathematic models used to calculate transmission capacity were analyzed. In order that the DLR system obtains the optimum dynamic capacity curve, a model combining the weather model （WM） with temperature-sag （TS） model was adopted. Simulation test verified validity and practicability of this model. Finally, the necessity and significance to use DLR in Chinese power grid were presented.