基于Monte Carlo的电铁电能质量预测方法

摘要

针对电气化铁路牵引负荷具有的非线性、单相独立性和随机波动性的特点,提出一种基于Monte Carlo抽样的电铁电能质量预测方法,从而分析新建电气化铁路对电网电能质量的影响.对于新建的电铁牵引变电所,该方法在适当的边界条件下选取匹配的牵引变电所实测数据作为基础样本,在容量等效后建立其负荷电流的基波及各次谐波的概率分布模型,然后生成一组随机数,以前面得到的概率分布模型为对象,采用Monte Carlo方法进行基波及谐波的抽样,从而得到预测的新建变电所负荷数据,并可结合谐波、负序潮流程序研究其对电力系统可能产生电能质量影响.实例表明该方法能够真实地模拟牵引实际物理过程,故解决问题与实际较符合,在工程上具有可行性和实用性.%According to the characteristics of the electrical traction load such as nonlinearity, single-phase independence and stochastic fluctuation, one prediction method based on Monte Carlo sampling is proposed to analyze the influence on power quality of power system caused by newly-built electrified railways. For newly-built traction substations, with this method, firstly, actual measured data of proper existing traction substation is selected as basic data; secondly, the probability distribution models of the fundamental and harmonic current are built after the capacity equalization and a group of random data should be generated; thirdly, the load current data of the newly-built traction substations could be gotten with the Monte Carlo model according to the probability distribution models set up before. Combined with the harmonics and negative-sequence power flow calculation program, the related power quality parameters can be gotten at last. The engineering example shows that the method can simulate the physical process of the electrical traction load objectively, so it is close to actual experiences and has feasibility and practicability in engineering.