Controller design for a nozzle-flapper type servo valve with electric position sensor

Abstract

The control performance of hydraulic systems is basically influenced by the performance of the electro-hydraulic servo valve incorporated in a hydraulic control system. In this study, the authors propose a control design to improve the control performance of a servo valve with a non-contact eddy current type position sensor. A mathematical model for the valve is obtained through an experimental identification process. A PI-D control together with a feedforward (FF) control is applied to the valve. To further improve the dynamic response of the servo valve, an input shaping filter (ISF) is incorporated into the valve control system. Finally, the effectiveness of the proposed control system is verified experimentally.