无刷双馈电动机功率绕组功率因数分析与控制

Analysis and Control of Power Winding Power Factor for Brushless Doubly-Fed Machine

无刷双馈电动机定子具有两套极数和供电频率都不相同的功率绕组和控制绕组,通过特殊结构转子的磁场调制作用,这2套绕组在气隙中除了产生同频率的磁场外,还会产生大量的低频谐波磁场,使得无功功率较传统双馈电动机大,造成电动机的功率因数低。目前,国内针对该问题已有的研究成果中定性结论多,试验数据少,并且也没有实现理想的效果。为解决此问题,通过对功率绕组和控制绕组电流产生的磁场进行分析,并提出了一种基于功率绕组功率因数的矢量控制方法,达到了改善功率绕组功率因数的目的。最后,通过仿真和试验研究进行对比分析,试验结果与理论相一致,从而证明了该种控制方法的正确性和实用性。

The brushless doubly-fed motor stator has two sets of power windings and control windings with different pole numbers and different power supply frequencies.The magnetic windings of the special structure rotors,in addition to generating magnetic fields of the same frequency in the air gap,a large number of low-frequency harmonic magnetic fields are generated.It makes the reactive power larger than that of the conventional double-fed motor,resulting in a low power factor of the motor.At present,there are many qualitative conclusions in the domestic research results on this issue,the experimental data is small and the ideal effect is not achieved.In order to solve this problem,the magnetic field generated by the power winding and the control winding current is analyzed.A vector control method based on the power factor of the power winding is proposed to improve the power factor of the power winding.Finally,through simulation and experimental research,the experimental results are consistent with the theory,which prove the correctness and practicability of the control method.