基于改进型MRAS的异步电机无传感器矢量控制策略研究

On improved speed sensorless vector control strategy of asynchronous machine based on MRAS

针对传统异步电机电压模型磁链估计算法存在积分初值与直流漂移问题,采用一阶惯性滤波器代替纯积分器,并将实际磁链经低通滤波,后用以补偿低通滤波器所引入的幅值与相位误差。应用Matlab建立改进型基于模型参考自适应的无速度传感器矢量控制系统模型,且异步电机以三电平简化算法SVPWM逆变器驱动。结果表明,辨识转速和反馈转速在电机启动、升降速、加载过程中有良好的一致性,转速辨识精度较高且具有良好稳态特性和动态响应能力。在给定转速变化和负载扰动情况下,系统具有鲁棒性。

To solve problems about integral initial value and DC drift existed in voltage model flux linkage estimation algorithm of traditional asynchronous machine, a first - order inertial filter is used to replace pure integrator and ac- tual flux linkage is used to go through low - pass filtering in ways to compensate amplitude and phase error caused by introduction of the low - pass filter. An improved speed sensorless vector control system based on MRAS is es- tablished by using Matlab software, and the asynchronous machine is driven by simplified three -level SVPWM in- verter. The results show that the system features a better consistency, between the estimated speed and the feed- back speed during the process of motor starting, lifting speed and loading; speed estimation is of higher accuracy with a better steady - state characteristic and dynamic response ability; a stronger robustness is demonstrated under the given speed variation and load disturbance.