基于数据分析的MGP并网系统电气端口的谐波特性

Harmonic characteristics on both sides of motor-generator pair(MGP)for renewable energy based on data analysis

针对高度电力电子化电网的谐波污染和超高占比新能源电网中次/超同步间谐波引发的次/超同步振荡问题,本文基于同步电机理论提出了新能源通过驱动同步电动机和同步发电机发电的新型并网结构。通过分析这种新型并网方式的惯性特性和机械隔离作用进一步研究了其两侧端口的谐波和间谐波特性,阐述了傅里叶分解法的原理及分解过程,针对所提出的新型并网方式结合傅里叶分解的数据分析方法进行谐波/间谐波特性的仿真和实验分析。在仿真系统中对不同工况下新型并网系统两端的电压曲线进行傅里叶频谱分析,数据分析得到的傅里叶频谱图证明了新型并网方式对谐波和间谐波的隔离衰减作用,并搭建了5 kW的实验系统,通过对新型并网方式实验系统两端的电压波形进行傅里叶分析,验证了理论分析和仿真结果。

In order to solve the problem of sub/supersynchronous oscillation caused by sub/supersynchronous harmonics in the harmonic pollution of high power electronic power grid and ultra-high proportion of new energy grid,this paper proposes a new grid connected structure of new energy by driving synchronous motors and synchronous generators based on the theory of synchronous motors.Based on the analysis of the inertia characteristics and mechanical isolation effect of this new grid connection mode,the harmonic and interharmonic characteristics.of the two sides for the new grid connection mode are studied.The principle and decomposition process of Fourier decomposition method are described.The simulation and experimental analysis of harmonic/interharmonic characteristics for the new grid connection mode are carried out based on the data analysis method of Fourier decomposition.In the simulation system,the voltage curves at both sides of the new grid connected system under different conditions are analyzed by Fourier spectrum.The Fourier spectrum obtained from data analysis proves the isolation and attenuation effect of the new grid connection mode on harmonics and inter harmonics.In the 5 kW experimental system,the theory analysis and simulation results are verified by Fourier analysis of voltage waveforms at both sides of the new grid connected experimentalsystem.