  The design of ideal internal dynamics (IID) generators, namely solving IID,
is a fundamental problem, which is a key step to handle the nonminimum-phase
output tracking problem. In this paper, for a class of unstable matrix
differential equations, a new causal dynamic IID generator is proposed, whose
parameters are partly chosen via H_2/H_inf optimization. Compared with existing
similar generators, it is applicable to matrix differential equations with
singular system matrices and is easily extended to slowly time-varying matrix
differential equations without extra computation.
