基于双馈风力发电机变流器的谐波分析

摘要

由于引入了变流器等电力电子装置,变速恒频双馈风力发电系统输出的电流中含有大量谐波,分析双馈风力发电机的谐波特性并减少其谐波含量,对风电并网具有重要意义.介绍了双馈电机的基波和谐波等效电路,在此基础上提出了双馈风力发电机转子侧变流器谐波分析方法,并用一台i.5 MW双馈电机进行了仿真验证.对电压空间矢量脉宽调制( SVPWM)的三种调制方式进行了研究,在1.5 MW双馈风力发电机满载和半载两种工况的仿真下,分析比较了SVPWM三种调制方式下的谐波情况,仿真结果表明采用七段式调制方式合成SVPWM时,双馈电机谐波含量最小.%With the introduction of converters and other power electronic devices, variable speed constant frequency double-fed wind power generation system was rich in a large number of harmonics. The harmonic characteristic of double-fed induction generator (DFIC) was analyzed and reduce the harmonic was of great significance to grid synchronization of wind power. The fundamental and harmonic equivalent circuit of DFIG were introduced, based on which a harmonic analysis method of DFIG rotor side converter was proposed, which was verified by simulation of a 1.5 MW DFIG. Three type method of voltage space vector PWM (SVPWM) modulation were studied. According to the simulation of full load and half load in a 1.5 MW DFIG, the harmonic condition of the three SVPWM modulation method were analyzed and compared. The simulation results showed that the harmonic contents of DFIG was the smallest when seven-segment SVPWM was used.