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Influence of control valve delay and dead zone on the stability of a simple hydraulic positioning system. (English) Zbl 1205.93047
Summary: This paper deals with the PI control of a highly simplified dynamic model of a hydraulic cylinder. It is assumed that the hydraulic fluid is incompressible and that the pump provides constant flow rates, which results in the possibility of velocity control. Two types of anomalies are taken into account: (a) the time delay due to the controller computations and the internal pressure dynamics and (b) the dead zone of the controller valve. This results in a nonlinear system described by a piecewise linear discontinuous map. The nonlinear behavior of the system is explored and the practically globally stable parameter domains are identified.
MSC:
93B51Design techniques in systems theory
93C95Applications of control theory
76B99Incompressible inviscid fluids, potential theory
93C10Nonlinear control systems