Relationship between availability of states and pole/zero cancellations in H/sub /spl infin//-control

This note compares servo systems designed with three methods of H/sub /spl infin//-control, that is, output feedback control, state feedback control and partial state feedback control. The three kinds of control use different information of the plant to generate the control input. We show that if more states are used, then the number of the pole/zero cancellations can be reduced.<
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