On Event-driven Control For Systems With Actuator Saturation

In the industrial control field, the updates of data acquisition and control signals are periodic, in other words, most of the control strategies in the industrial field are time-triggered. After years of developments, the time-triggered control strategy has had a set of complete theoretical system, however, its shortcomings of conservative control and large number of communication and control signal compute restrict its further development. Therefore we need to consider event-driven control strategy. Event-driven control strategy is different from the traditional time-triggered control strategy, its calculation of control signal is driven by the specific event rather than time. Event-driven control strategy has some advantages, such as:reducing the calculation of control signal and numbers of control information transmission and reducing the load of network, which make it become the hot topic.Systems with actuator saturation are common seen and very meaningful in the industrial field, and they have the typical nonlinear characteristics, which can affect the performance of the system, and even make the system unstable. In this paper, we applied event-driven control strategy for systems with actuator saturation, and we obtained some meaningful results under the s domain and time domain, respectively. Firstly, anti-windup event-driven PID control strategy was studied, aimed at unstable system with actuator saturation, we proposed an improved event-driven PID control strategy, which shown that the number of calculation and communication could be further reduced, and the better control performance was also guaranteed. Then, aimed at continuous system with actuator saturation which contained external model disturbance, an observer-based event-driven output feedback control scheme was proposed. We presented the observer design methods and event-driven control algorithm, obtained the ultimate bounded stability criterion. Finally, we were interested in event-driven dynamic output feedback control for systems with actuator saturation. The design method of dynamic output feedback controller was proposed. Stability criterion was given through stability analysis of event-driven dynamic output feedback control loop.This paper also introduced physical simulation object ball and beam system, including the features and components of ball and beam system and modeling of the system. We applied position control of the ball and beam system to verify the stabilization and effectiveness of the proposed event-driven control algorithm.