额定功率下高速机车谐波特性的仿真分析

通过综合分析高速机车脉宽调制(PWM)整流器谐波电压产生的过程和牵引供电系统的谐波阻抗特性,对高速机车以额定功率运行时谐波的动态特性进行了计算和分析.采用双傅立叶级数和Bessel函数推导出PWM整流器谐波电压的计算式;基于分布参数模型导出了接触网谐波阻抗的表达式,进而对串联、并联谐振进行了分析.在此基础上,对机车在额定功率下的谐波电压和谐波电流进行了仿真计算和频谱分析.结果表明:谐波电压和谐波电流的频谱特性均与机车位置有关,尤其是谐波电流的变化更大;特定次谐波在特定线路位置发生串联谐振,且谐振位置随机车位置变化;谐波电流含量很小,主要集中在3～9次低次谐波和发生串联谐振的频带.

Simulation Analysis of Dynamic Characteristic of Harmonics for High-Speed Locomotive Running at Rated Power

An analytical method for calculating the dynamic characteristic of the harmonics of high-speed locomotives running at a rated power was presented by analyzing the generation process ofharmonic voltage and the characteristics of harmonic impedance of a traction power supply system.Based on the double Fourier series and the Bessel function,the expression of harmonic voltage of aPWM(pulse width modulation)rectifier was deduced.Based on the distributed parameter model theformula of calculating harmonic impedance for an overhead contact system was,derived,and from theformula,series resonances and parallel resonances were analyzed.Frequency spectrum characteristicsof harmonic voltage and harmonic current under the condition that a hJish-speed locomotive runs at arated power were simulated and analyzed.The research results indicate that the frequency spectrumcharacteristics of both harmonic current and harmonic voltage vary,especially the former;seriesresonances occur at some frequency and the resonance position depends on locomotive position alongthe line;harmonic current contents are small,and the main contents are the 3rd t0 9th and seriesresonance harmonies.