This paper deals with the robust control of time–
delay non–integer order plants by means of standard noninteger
order controllers. Precisely, a method for determining
the parameter regions where a PIλDμ controller ensures a
given modulus margin (inverse of the H1 norm of the sensitivity
function) is presented. This method, which is conceptually simple
and intuitive, extends to the aforementioned general classes of
controllers and plants the approach recently followed by the
present authors in the integer–order case. A Matlab R⃝ program
to plot the loci of constant modulus margin and those of constant
crossover frequency has been written and applied to some
numerical examples taken from the literature.
