Proposal of perfect tracking and perfect disturbance rejectioncontrol by multirate sampling and applications to hard disk drivecontrol

摘要

Multirate two-degree-of-freedom controllers are proposed fordigital control systems, where there is a restriction that the speed ofthe A/D converters are slower than that of the D/A converters. Theproposed feedforward controller assures the perfect tracking at Minter-sampling points. Moreover, the proposed feedback controllerassures the perfect disturbance rejection at M inter-sample points inthe steady state. Illustrative examples of position control for harddisk drive are presented, and the advantages of this approach aredemonstrated