电气化铁道牵引变电站的谐波分布由系统背景谐波和牵引负荷谐波共同决定。牵引负荷具有明显的波动性和随机性,通常牵引变电站存在一定的空载概率。首先,结合牵引变电站高压侧母线谐波电压的概率分布特征,构建了含有多个参变量的概率密度函数,用于描述系统背景谐波和牵引负荷发射谐波的叠加结果。然后,提出了利用模拟退火算法进行曲线拟合从而辨识所建模型参数的方法和步骤,从而得到牵引负荷谐波的发射水平。通过实例计算,证明了所述方法的可行性和实用性。
The harmonic distribution of a traction substation is determined by the traction load harmonics and the system background harmonics.The traction load is essentially random and fluctuating,so there is generally a certain proportion of no-load for a traction substation.Considering the probabilistic characteristics of harmonic voltage on the high-voltage bus of substations,a multi-parameter probability distribution function is proposed to describe the distribution of the superposition of background harmonic voltages and traction load harmonic voltages.Using the simulated annealing algorithm,a curve fitting approach is put forward,which can be used to identify the parameters and then to confirm the harmonic emission levels of traction loads.Finally,the feasibility and practicability of the proposed method are validated by actual case calculations.