Optimized Feedback Control or Dead-Time Plants by Complementary Feedback

This paper deals with feedback control of controlled systems with dominant dead time. It is shown in which way the special difficulties arising with the presence of dead time in a controlled system can be overcome by means of so-called ``complementary feedback,'' so that an optimal control performance will be achieved. In addition, both the influence of unavoidable errors in the technical realization of this principle and the question of the best-suited type of controller will be discussed. Finally, several ways of realization and their adjustment are discussed, and a concept is given for a self-adjusting control in case the dead time of the controlled system is variable.