该文研究了一种感应电机无速度传感器模型参考自适应系统(model reference adaptive system,MRAS),提出一种新型的基于自适应磁链观测器的常数增益速度辨识方法。首先,运用李亚普诺夫(Lyapunov)稳定性理论设计出自适应磁链观测器及速度估算方法,通过MATLAB中的线性矩阵不等式(linear matrix inequality,LMI)工具箱求解线性矩阵不等式获得磁链观测器的增益矩阵,保证了此磁链观测器的稳定性,同时也克服了运用极点配置方法带来不稳定区域的问题。该文还研究了基于自适应观测器的电阻辨识问题。基于给出的自适应磁链估计方法,设计了感应电机无速度传感器直接转矩控制系统,并进行了MATLAB仿真和实验,结果表明,提出的无速度传感器速度方法在全速范围内具有很好的动态和静态性能。
This paper describes a model reference adaptive system(MRAS) for speed control of the induction motor drive(IM) without a speed sensor.In this scheme a new adaptive flux observer with a constant gain for speed estimation is presented.The theory of Lyapunov stability is used to design adaptive flux observers and speed estimators.The stability of flux observer is guaranteed by a linear matrix inequality(LMI),and the constant observer gain is obtained by solving the LMI with LMI toolbox in MATLAB.The problem of unstable region which arises from using pole-placement technique is overcome.Meanwhile,this paper also studies the resistance identification problem based on the adaptive observer.Based on the proposed approach of flux estimation,the sensorless direct torque control induction motor drive system is designed.The MATLAB simulation and experimental results show that the speed sensorless direct torque control IM drive system is capable of working from very low speed to high speed and shows good dynamic and steady-state performances.