Robust Control Toolbox™

Coprime stability margin of plant-controller feedback loop

Syntax

• [MARG,FREQ] = cpmargin(P,C) 
  [MARG,FREQ] = cpmargin(P,C,TOL) 
  

Description

[MARG,FREQ] = cpmargin(P,C) calculates the normalized coprime factor/gap metric robust stability of the multivariable feedback loop consisting of C in negative feedback with P. C should only be the compensator in the feedback path, not any reference channels, if it is a two degree-of-freedom (2-DOF) architecture. The output MARG contains upper and lower bound for the normalized coprime factor/gap metric robust stability margin. FREQ is the frequency associated with the upper bound.

[MARG,FREQ] = cpmargin(P,C,TOL) specifies a relative accuracy TOL for calculating the normalized coprime factor/gap metric robust stability margin. (TOL=1e-3 by default).

See Also
loopmargin  Comprehensive analysis of feedback loops

gapmetric   Compute the gap and the Vinnicombe gap metric

wcmargin    Worst-case disk gain/phase margins for plant-controller feedback loop

Provide feedback about this page

cmsclsyn

dcgainmr

© 1984-2008- The MathWorks, Inc.    -   Site Help   -   Patents   -   Trademarks   -   Privacy Policy   -   Preventing Piracy   -   RSS