Package: TuningGoal
Frequencyweighted gain constraint for control system tuning
Use the TuningGoal.WeightedGain
object to specify
a tuning requirement that limits the weighted gain from specified
inputs to outputs. The weighted gain is the maximum across frequency
of the gain from input to output, multiplied by weighting functions
that you specify. You can use the TuningGoal.WeightedGain
requirement
for control system tuning with tuning commands such as systune
or looptune
.
After you create a requirement object, you can further configure the tuning requirement by setting Properties of the object.
creates
a tuning requirement. This tuning requirement specifies that the closedloop
transfer function, H(s), from
the specified input to output meets the requirement:Req
=
TuningGoal.WeightedGain(inputname
,outputname
,WL,WR
)
W_{L}(s)H(s)W_{R}(s)_{∞} < 1.
The notation •_{∞} denotes the maximum gain across frequency (the H_{∞} norm).

Input signals for the requirement, specified as a string or as a cell array of strings, for multipleinput requirements. If you are using the requirement to tune a Simulink^{®} model
of a control system, then
If you are using the requirement to tune a generalized statespace
(
For example, if you are tuning a control system model, If
For more information about analysis points in control system models, see Marking Signals of Interest for Control System Analysis and Design. 

Output signals for the requirement, specified as a string or as a cell array of strings, for multipleoutput requirements. If you are using the requirement to tune a Simulink model
of a control system, then
If you are using the requirement to tune a generalized statespace
(
For example, if you are tuning a control system model, If
For more information about analysis points in control system models, see Marking Signals of Interest for Control System Analysis and Design. 

Frequencyweighting functions, specified as scalars or as SISO or MIMO numeric LTI models. The functions WL(s)H(s)WR(s)_{∞} < 1.
WL = tf(1,[1 0.01]); WR = 10; If you specify MIMO weighting functions, then A value of 

Frequencyweighting function for the output channels of the
transfer function H(s) to constrain,
specified as a scalar, or as a SISO or MIMO numeric LTI model. The
initial value of the 

Frequencyweighting function for the input channels of the transfer
function to constrain, specified as a scalar or as a SISO or MIMO
numeric LTI model. The initial value of the 

Frequency band in which tuning requirement is enforced, specified
as a row vector of the form Set the Req.Focus = [1,100]; Default: 

Stability requirement on closedloop dynamics, specified as
1 ( By default, Default: 1( 

Input signal names, specified as a cell array of strings. These
strings specify the names of the inputs of the transfer function that
the tuning requirement constrains. The initial value of the 

Output signal names, specified as a cell array of strings. These
strings specify the names of the outputs of the transfer function
that the tuning requirement constrains. The initial value of the 

Models to which the tuning requirement applies, specified as a vector of indices. Use the Req.Models = 2:4; When Default: 

Feedback loops to open when evaluating the requirement, specified as a cell array of strings that identify loopopening locations. The tuning requirement is evaluated against the openloop configuration created by opening feedback loops at the locations you identify. If you are using the requirement to tune a Simulink model
of a control system, then If you are using the requirement to tune a generalized statespace
( Default: 

Name of the requirement object, specified as a string. For example, if Req.Name = 'LoopReq'; Default: 
When you tune a control system using a TuningGoal
object
to specify a tuning requirement, the software converts the requirement
into a normalized scalar value f(x). x is
the vector of free (tunable) parameters in the control system. The
software then adjusts the parameter values to minimize f(x)
or to drive f(x) below 1 if
the tuning requirement is a hard constraint.
For the TuningGoal.WeightedGain
requirement, f(x)
is given by:
$$f\left(x\right)={\Vert {W}_{L}T\left(s,x\right){W}_{R}\Vert}_{\infty}.$$
T(s,x)
is the closedloop transfer function from Input
to Output
. $${\Vert \text{\hspace{0.17em}}\cdot \text{\hspace{0.17em}}\Vert}_{\infty}$$ denotes
the H_{∞} norm (see norm
).
evalSpec
 looptune
 looptune
(for slTuner)
 slTuner
 systune
 systune (for slTuner)
 viewSpec