磁饱和及参数变化对速度观测器精度的影响

Saturation and Parameter Variation Influence Precision of Observer

在矢量控制感应电动机系统中,当电机参数发生变化,或出现磁路饱和时,将会影响速度控制的准确性,使速度观测器精度受影响.通过MATLAB/SIMULINK仿真系统,建立静止坐标系下考虑磁饱和的感应电动机模型和矢量控制系统模型,并通过改变电机参数,比较分析参数变化及磁饱和效应对自适应状态观测器速度估计的影响.研究结果证明感应电机在参数变化时会给速度估计带来一定误差,特别是转子电阻发生变化时误差最大;工作在弱磁区时,磁饱和效应会明显影响速度观测器的精度,带来较大转速估计误差,应对观测器进行磁饱和补偿以提高矢量控制系统的调速性能.

The authors analyze the influence in vector controlled induction machine caused by parameter variation and main flux saturation affects speed estimation of adaptive state observer. According to simulation of the modified scheme with saturated induction motor model, it is proved that when the vector control scheme operates in field weakening region, the main flux saturation will obviously influence precision of speed observer and bring great error of speed estimation. Thereby, the main flux saturation should be compensated to improve performance of the vector control system.