control.disk_margins
- control.disk_margins(L, omega, skew=0.0, returnall=False)[source]
Disk-based stability margins of loop transfer function.
- Parameters:
- L
StateSpaceorTransferFunction Linear SISO or MIMO loop transfer function.
- omegasequence of array_like
1D array of (non-negative) frequencies (rad/s) at which to evaluate the disk-based stability margins.
- skewfloat or array_like, optional
Skew parameter(s) for disk margin (default = 0.0):
skew = 0.0 “balanced” sensitivity function 0.5*(S - T)
skew = 1.0 sensitivity function S
skew = -1.0 complementary sensitivity function T
- returnallbool, optional
If True, return frequency-dependent margins. If False (default), return worst-case (minimum) margins.
- L
- Returns:
- DMfloat or array_like
Disk margin.
- DGMfloat or array_like
Disk-based gain margin.
- DPMfloat or array_like
Disk-based phase margin.
Examples
>> omega = np.logspace(-1, 3, 1001) >> P = control.ss([[0, 10], [-10, 0]], np.eye(2), [[1, 10], [-10, 1]], 0) >> K = control.ss([], [], [], [[1, -2], [0, 1]]) >> L = P * K >> DM, DGM, DPM = control.disk_margins(L, omega, skew=0.0)