基于速度关联函数的感应电机磁链观测研究

Research on Flux Observation of Induction Motors Based on Speed Dependent Function

针对电压模型磁链估算器仅适用于高速运行场合,而电流模型磁链估算器只在低速运行情况下才有效的问题,结合二者各自的优点,提出了一种新的在宽调速范围内适用的理想混合磁链观测器。首先论述了电压模型和电流模型的优缺点,引入了速度关联函数的概念,速度关联函数通过频率选择,使混合模型在低速时运行电流模型,而高速时运行电压模型,并使高低速在相互转换的过程中平滑过渡。所提出的混合转子磁链观测器的有效性通过Matlab/Simulink仿真研究进行了验证,仿真结果证明了基于速度关联函数的混合磁链观测器提高了磁链观测在全速范围的精度及有效性,并且结构简单,算法可靠,易于工程实现,同时对外部负载扰动具有较好的鲁棒性。

The voltage model flux estimator is suitable only for high speed operation whereas the current model flux estimation is valid only for low speed operation. In view of this, a new ideal hybrid flux estimator with advantages of the voltage model and the current model for wide speed range is proposed. Firstly, advantages and disadvantages of the voltage model and the current model are elaborated and the concept of the speed dependent function is introduced, by frequency selection, the speed dependent function let the hybrid model use the current model at low speed, while the voltage model at high speed, and transit smoothly in the process of converting to each other. The proposed method is validated under Matlab/Simulink and it is shown that the hybrid estimator using a speed dependent function improves the flux estimation accuracy, and is valid for all speed range. It has simple structure, reliable algorithms, better robustness to the external load disturbance, and is easy to realize.