DSP Control of Electro-Hydraulic Servo Actuators

Hydraulic actuators are characterized by their ability to impart large forces at high speeds and are used in many industrial motion systems. In applications where good dynamic performance is important it is common to contain the actuator in a servo loop comprising a feedback transducer and electronic controller. The majority of electronic servo-controllers used in these systems are analogue based implementations of the well-known PID type. However, the requirement to implement advanced control strategies has led to an increased interest in the use of digital signal processors (DSPs) in this field. One design approach which merits special consideration is the use of computer simulation software to model the hydraulic plant and electronic servo-controller, and to generate and test embedded code for the target DSP. This application report discusses some of the issues involved in controlling linear hydraulic actuators, and the suitability of the TMS320C28xTM DSP for such systems.