STUDIES OF SECOND- AND THIRD-ORDER CONTACTOR CONTROL SYSTEMS

摘要

The majority of this paper is devoted to the study of the response of second- and third-order contactor systems with linear switching that is, switching according to the sign of a linear combination of the error and its derivatives. The example chosen for the third-order system is a simplified equation of the pitching motion of a missile whose control surface takes on only two positions, full up or full down. The performance of these systems during chatter operation and during their response to step inputs is studied in great detail.nThe results show that for certain rather wide ranges of combinations of natural damping of the controlled process and step input, amplitude, there is very little difference between optimum and linear switching response. In order to extend the range of step inputs for which nearly optimum response can be obtained without using a complicated optimum switching function, a quasi-optimum switching function is suggested which requires only a two-dimensional function generator. Experiments showed that the response with this switching function was very nearly optimum for a wide range of step inputs.