On a new class of multistage fractional-order phase-lead compensators

Abstract

This paper proposes the transfer function forms for implementing a new class of fractional-order phase-lead compensators of analog type. A serial structure of frequency-scaled second-order compensators is defined to reduce the sensitivity to the tolerance of passive components in analog implementations. Compared to conventional multiple realizations, the new structure considerably increases the frequency range in which the phase plot of the compensator shows a flat behavior, and easily locates this range in the desired position. The new compensator gives new chances of flexible and robust control system design.