Regularization of singular H2 and H∞ control problems

Presents a regularization method for treatment of the singular H _∞ control problem with dynamic measurement feedback in the case when the system output to be controlled depends only on the state variables and the transfer matrix from the input to the to-be-controlled output has a pole-zero excess of 1. The solution to the problem is based on its conversion into a standard H_∞ suboptimal control problem. The method is also developed for a singular H₂ control problem which is studied in parallel. A surprising fact is that, in contrast to the standard case, the singular H₂ optimal controller differs from the corresponding singular linear quadratic Gaussian regulator