双馈风力发电机电流谐波分析

由于变速恒频发电系统中交-交变频器输出电压中含有大量谐波,导致发电机输出电能质量无法满足实际需求.针对这一问题,在分析双馈发电机数学模型的基础上,对双馈发电机转子侧输入非标准正弦电压情况,以及定子侧电压出现三相不平衡情况时,电机定子及转子侧的电流进行傅里叶分解,分解为基波电流和一系列谐波电流,得到各次谐波幅值及其频率,从而进行谐波分析和仿真研究,验证分析方法的正确性.

Harmonic analysis of current in double-fed wind generator

The electro-power quality of double-fed wind generator(DFWG) with AC-to-AC cycloconverter cannot meet the need of power system because of a great number of harmonics takes place in the output voltage of the cycloconverter adopted.Aimed at this problem,based on the analysis of DFWG model,two cases were considered,namely:(1) non-sinusoidal rotor voltage injection and,(2) an unbalanced stator voltage.In both cases,Fourier analysis was conducted to decompose the non-sinusoidal currents into a fundamental component and a series of harmonic components.Therefore the amplitude and frequency of the the harmonics with all orders were obtained and the harmonic analysis and simulation investigation were carried out to verify the validity of the analysis method proposed.