抄録
When a given plant has poles on the jω axis in the two block mixed sensitivity problem setting, they become the zeros of G12 or G21 in the generalized plant, and the H∞ control problem becomes a nonstandard one. To circumvent this problem on zeros, the authors introduce a loop transforming technique and the extended H∞ control theory, previously proposed by authors, and derive an H∞ controller. The results include a design method of a servo system where the poles of the plant or/and the designed controller play a role of the internal model. This particularly is useful in designing motion control systems because one often models actuators to have single or double integlators when the damping coefficient and/or the spring coefficient are small but uncertain.
