THE CALCULATION OF REAL-MU AND CONTROLLER-DESIGN

For a SISO, linear and time-invariant plant, with one real parameter u ncertainty and one complex fictitious perturbation representing perfor mance uncertainty, the structured singular value, mu(DELTA)(M), is cal culated. Then mu - K iteration can be used to design a mu-optimal cont roller. A simple design example is considered. The results are compare d with those obtained for the same system with the real parameter mode lled as a complex perturbation. This illustrates the conservatism that can be introduced by treating real uncertainty as complex uncertainty .