基于暂态等效风速系数的高压架空线路载流量估计*

基于等效风速系数的架空线路载流量估计方法无需风速和风向参数,具有计算简单和精度高的优势;但由导线稳态热平衡方程推得,使用时要求线路温度和等效风速系数处于稳定状态,一定程度上限制了方法的精度。为此,提出一种基于暂态等效风速系数的线路载流量估计方法。首先利用导线非稳态热平衡方程计算暂态等效风速系数,再结合马尔科夫链方法模拟导线在不同电流下的温度变化,最后通过概率方式估计线路载流量。利用导线载流温升实验平台对所提方法进行了实验验证。结果表明,即便导线温度和风速系数处于波动状态,所提方法也可在不依赖风速和风向条件下,准确估计线路载流量。

Calculation for Overhead Line Ampacity Based on Transient and Equivalent Wind Coefficient

Without the parameters of wind speed and direction, method of equivalent wind coefficient for overhead line ampacity has an advantage of simple calculation and high accuracy. However, it is deduced from stable Heat balance equation and required that the line temperature and equivalent wind coefficient are in stable, which the accuracy is limited. So, a method of calculation for overhead line ampacity based on transient and equivalent was provided in this paper. The method used conductor transient Heat balance equation to calculate transient and equivalent wind coefficient first. Then, it was combined with Markov Chan to simulate temperature varieties of conductor in the different conditions of current. At last, it calculated the line ampacity by probability. It was tested by a conductor temperature experimental platform. The results show that the method provided can calculate line ampacity accurately independed on wind speed and direction, even if line temperature and equivalent wind coefficient are in fluctuating.