Derivative and proportional state feedback for linear descriptor systems with variable coefficients (Q1361783)

This paper considers linear time-varying descriptor control systems in the form \(Ex'- Ax- Bu= 0\), \(y= Cx\). Thus \(E\), \(A\), \(B\), \(y\) all vary with time. Results are given which characterize when linear time-varying proportional and derivative output feedback controls, \(u= Fy+ Gy'+ v\), with \(G\), \(F\) time-varying, regularize the original system. That is, the feedback reduces the system's index to at most one.