非整数阶系统的频率辨识

Identification of non-integer-order systems in frequency domain

使用频响数据对非整数阶系统作频域模拟和辨识.首先,定义了非整数阶微分器的频率特性,进而给出了非整数阶系统的奈奎斯特曲线的绘制方法.然后,运用方程式误差的辅助变量法,根据实部和虚部频率数据进行非整数阶系统的频率辨识.最后,通过两个数字仿真来验证这种辨识方法.

The modeling and identification of non-integer-order systems using frequency-response data are studied. The frequency characteristic of a non-integer-order differentiator is defined and a method to obtain the Nyquist plot of a non- integer-order system is given. Based on the least squares technique and an instrumental variable, the identification of the non-integer-order system is performed using the real and imaginary parts of the frequency response. Finally, two simulation examples illustrate this methodology.