永磁风力发电机无位置传感器PFC整流控制

针对采用永磁同步发电机(PMSG)的小型风力发电系统中因不控整流导致的发电机电流谐波大、整流电压不可控等问题,采用一种利用单相功率因数校正(PFC)电路对PMSG每相定子绕组分别整流的方法,提出了该PFC整流系统的无位置传感器控制算法。利用PMSG和PFC主电路的数学模型,估算出发电机感应电动势;设计一种等效积分器,用于电动势观测转子磁链;用锁相环(PLL)检测发电机磁链矢量相位,为PFC电流控制提供参考。仿真和实验结果表明,采用该控制算法的PFC电路能有效地抑制发电机电流谐波,稳定整流输出电压。

Sensorless Control of PFC Rectifiers for a PMSG Wind Generation System

In order to overcome the drawbacks such as high current harmonics and uncontrollable output voltage of the permanent magnetic synchronous generator(PMSG) with a diode rectifier in a small wind generation system,a controllable rectifying system is used which employs one-phase power factor correction(PFC) circuit for each phase of the PMSG.Its sensorless control strategy is advanced.The electromotive force(EMF) of the PMSG is reconstructed based on the models of the PMSG and the PFC circuits;the rotor flux linkage is observed by using an equivalent integrator which simply delays the EMF signal for 90°,and the phase angle for current control of the PFC circuit is derived from the rotor flux linkage by using a phase locked loop(PLL).Results of both simulation and experiments on a 2kW prototype platform verify that the PFC circuit adopting the control strategy can effectively suppress the harmonics in PMSG currents and keep the output DC voltage constant.