Generalized theory of synthesis of control systems of zero-order/instantaneous dynamics and infinite disturbance rejection ratio

A generalized theory for the synthesis of control systems of zero-order/instantaneous response and infinite disturbance rejection ratio is presented. This theory demonstrates the possibility of using feedforward algorithms to achieve the zero-order dynamics and infinite disturbance rejection ratio, while sensing/estimating some, rather than all, of the system state variables. This possibility is explored and used in an application of the generalized theory to synthesizing electric motor drive systems, effectively operating in an open-loop mode, to provide for the zero-order dynamics and infinite disturbance rejection ratio. A differentiation-free algorithm, whereby n local positive feedback state variable differentiators are replaced by direct sensing/estimating state variable derivatives and feeding them back in a positive feedback manner, is shown