小波变换和改进谐波法的感应电动机转速辨识

摘要

Aiming at the problem that the open-loop and closed-loop control of induction motor speed sensorless depends on the mathematical model, a digital low-pass filter composed of adaptive neural network and wavelet transform was built.The improved rotor slot harmonic speed identification method based on stator magnetic field orientation was proposed.The stator flux was identificated by the wavelet transform.The digital low-pass filter was used to eliminate the influences of such disturbance factors as the harmonic signal,white noise and frequency variation, and thus ensure the accurate extraction of rotor slot harmonic voltage.The simulation and experimental results show that the present method has strong robustness and the signals can be detected under strong noise.Thus, the speed identification accuracy is effectively enhanced, the speed can be adjusted in the wider range, and the dynamic performance and low speed performance get improved.%针对感应电动机无速度传感器开环、闭环控制依赖数学模型的问题,建立了由自适应神经网络与小波变换构成的数字低通滤波器,并给出定子磁场定向改进转子槽谐波辨识转速的方法.利用小波变换辨识定子磁链,数字低通滤波器消除谐波信号、白噪声、频率变化等干扰因素的影响,保证准确提取转子槽谐波电压.仿真实验结果表明,该算法具有较强的鲁捧性,可在强噪声下进行信号检测,有效提高转速的辨识精度,使转速可以在很宽的范围内进行调整,并可改善其动态性能和低速性能.