Simulink Control Design™ - MathWorks

Tips

• To assert that the gain margin is satisfied, select both Include gain and phase
  margins in assertion on page 16-201 and Enable assertion on page 16-215.


• You can add or modify gain margins from the plot window:
  
  
  • To add new gain margin, right-click the plot, and select Bounds > New Bound.
    Select Gain margin in Design requirement type, and specify the margin in
    Gain margin.
  
  
  • To modify the gain margin, drag the segment. Alternatively, right-click the plot, and
    select Bounds > Edit Bound. Specify the new gain margin in Gain margin >.
  
  
  
  

You must click Update Block before simulating the model.

Command-Line Information
Parameter: GainMargin
Type: character vector
Value: [] | 20 | positive finite value. Must be specified inside single quotes ('').
Default: '[]' for Nichols Plot block, '20' for Check Nichols Characteristics block.

See Also

Plot Linear Characteristics of Simulink Models During Simulation on page 2-82

“Verify Model at Default Simulation Snapshot Time” on page 14-6

Phase margin (deg) >

Phase margin, in degrees.

By default, negative feedback, specified in Feedback sign on page 16-129, is used to
compute the phase margin.

Settings
[] for Nichols Plot block.
30 for Check Nichols Characteristics block.

• Positive finite number for one bound.


• Cell array of positive finite numbers for multiple bounds.

Nichols Plot