一种基于虚拟阻尼绕组的双馈电机灭磁方法

A flux damping mothod of doubly-fed induction generator

针对电网故障引发的双馈电机磁链阻尼振荡问题,提出一种基于虚拟阻尼绕组的灭磁控制方法。首先根据双馈电机的电磁关系分析了在电网故障下定子磁链的动态变化过程。在此基础上建立了双馈电机矢量控制的数学模型。通过MATLAB软件进行仿真实验,对比分析了改进与常规控制策略下,电压跌落和电压骤升后定子磁链d轴分量与定子磁链q轴分量的变化波形。改进的灭磁方法可有效对抗磁链的振荡冲击,提升了双馈风力发电机在电网故障下的运行性能。

This paper proposes a demagnetization control method based on virtual damping winding,when power grid faults cause magnetic damped oscillation about doubly-fed induction generator.Firstly,the dynamic change process of stator flux under power grid faults is analyzed,which is based on the electromagnetic relationship of doubly-fed motors.And then,a mathematical model of vector control for doubly-fed motor is established.Through simulation experiments using MATLAB software,comparative analysis about waveform on the d-axis and q-axis of the stator flux after voltage drop and voltage surge are conducted between the improved control strategy and the conventional control strategy.The improved demagnetization method can effectively counteract the oscillation shock of the magnetic flux linkage,and improve the operational performance of doubly-fed induction generator under grid faults.