MIMO 稳定图

打开实时脚本

计算由随机噪声激励的两输入/两输出系统的频率响应函数。

加载数据文件。使用包含 5000 个采样的汉宁窗和相邻数据段之间 50% 的重叠来计算频率响应函数。指定输出测量值为位移。

load modaldata
wl = 5000;

[frf,f] = modalfrf(Xrand,Yrand,fs,hann(wl),wl/2,Sensor="dis");

生成一个稳定图以标识最多 20 个物理模式。

modalsd(frf,f,fs,MaxModes=20)

Figure contains an axes object. The axes object with title Stabilization Diagram, xlabel Frequency (kHz), ylabel Model Order contains 4 objects of type line. One or more of the lines displays its values using only markers These objects represent Stable in frequency, Stable in frequency and damping, Not stable in frequency, Averaged response function.

重复该计算，但现在收紧稳定性标准。如果给定极点的固有频率随着模型阶数的增大而变化小于 0.01%，则将该极点归类为频率稳定的极点。如果随着模型阶数的增大，阻尼比估计值的变化小于 0.2%，则将给定极点归类为阻尼稳定的极点。

modalsd(frf,f,fs,MaxModes=20,SCriteria=[1e-4 0.002])

Figure contains an axes object. The axes object with title Stabilization Diagram, xlabel Frequency (kHz), ylabel Model Order contains 4 objects of type line. One or more of the lines displays its values using only markers These objects represent Stable in frequency, Stable in frequency and damping, Not stable in frequency, Averaged response function.

将频率范围限制在 0 到 500 Hz 之间。将频率的稳定性标准放宽至 0.5%，阻尼放宽至 10%。

modalsd(frf,f,fs,MaxModes=20,SCriteria=[5e-3 0.1],FreqRange=[0 500])

Figure contains an axes object. The axes object with title Stabilization Diagram, xlabel Frequency (Hz), ylabel Model Order contains 4 objects of type line. One or more of the lines displays its values using only markers These objects represent Stable in frequency, Stable in frequency and damping, Not stable in frequency, Averaged response function.

使用最小二乘有理函数算法重复该计算。将频率范围限制在 100 Hz 到 350 Hz 之间，并识别多达 10 个物理模式。

modalsd(frf,f,fs,MaxModes=10,FreqRange=[100 350],FitMethod="lsrf")

Figure contains an axes object. The axes object with title Stabilization Diagram, xlabel Frequency (Hz), ylabel Model Order contains 4 objects of type line. One or more of the lines displays its values using only markers These objects represent Stable in frequency, Stable in frequency and damping, Not stable in frequency, Averaged response function.

另请参阅

| |

主题