介绍了双馈电机的数学模型,并在此基础上总结了双馈电机定子电流谐波的来源和基本特点;基于对一台30 kW和一台1.5 MW双馈电机的具体试验数据,结合理论分析得到了齿谐波、开关谐波、电网电压引入的谐波等各种电流谐波的频谱特征,总结了定、转子谐波电流之间的关系;根据各种谐波的特点提出了减小定子电流谐波的方法,并将这些方法应用在1.5 MW双馈风力发电样机系统中,给出了满容量发电时的电流谐波试验结果,验证了这些方法的实用性。
The mathematic model of DFIG is introduced,based on which the sources and basic characteristics of stator current harmonics are analyzed and summarized.Based on the experimental data of a 30 kW DFIG and a 1.5 MW DFIG and combined with the theoretic analysis,the spectrum characteristics of different harmonic types are presented,such as slot harmonics,switching harmonics,grid-voltage-induced harmonics.The relationship between stator and rotor harmonic currents is summarized.According to the characteristics of each harmonic type,the ways to reduce the stator harmonic current are given and applied to a prototype of 1.5 MW DFIG.Results of current harmonic experiment at rated capacity are given and their validity is verified.