Active Disturbance Rejection Controller Design For A Class Of Distributed Parameter Systems

Active disturbance rejection controller (ADRC) as a new kind of control algorithm is developed in recent years, which can take the uncertainty and disturbance in the system as a whole interference. The whole disturbance named "total disturbance", is the core of ADRC, which is first put forward by Han Jingqing. In this way of design, one can solve the problem of immunity systems by synthetically considering the system internal uncertainty and extremal disturbance as a whole part and using observer and main controller to estimation and compensation. ADRC can be used out of an accurate model of system and can be applied to complex object. Thereafter Gao Zhiqiang put forward the idea of "bandwidth", then the classical ADRC is simplify in a linear way. The linear active disturbance rejection control (LADRC) is used in lots of areas because it is simple and practical, and many researchers take it into research and application. Distributed parameter systems (DPS) is a kind of systems that widely exist in each point of nature. It can be seen here and there, which is the reason why we take the subject of designing a related controller of DPS as a meaningful subject. However, DPS is more complicated the lumped parameter system, many uncertain factor existing, such as uncertain disturbance and parameter perturbation and so on. These unpredictable disturbance has great influence on the performance of the system, and using traditional control algorithm usually can't reach the ideal control effect. This article attempts to change the control problem of DPS into an immunity problem of system. The main research content of this article is as follows:1. In this paper, a class of linear PDF is studied, which can be described by first order partial differential equation (FOPDE). Taking the influence from the complexity, uncertainty and disturbance of input and output into consideration, this paper mainly research the dynamic control problem. This paper try to change the boundary control problem of the distributed parameter systems into an immunity problem, then design ADRC controller.2. This paper use the high order state observer to further approximate total disturbance, then based on the structure design higher order extended state observer (ESO). The purpose of this design is to achieve better estimation of the "total disturbance", and to overcome the effect of the system. The observer designed can get accuracy tracking result, make the state estimation more accurate, and retain the advantages that the controller structure is simple. The modified ADRC is applied on two simulation experiments, and compared with the classic PI controller designed by the former. What's more, the simulation shows that the improved ADRC can achieve good control effect.3. This paper suck up the predecessors'works, and get inspired from fact that immune PID can enhance the control effect of PID. The ideas that the immune PID can make parameter self-setting is used in the ADRC, that is to say an immune factor is added at nonlinear state error feedback (NLSEF) which is a mainly part of ADRC, and the immune mechanism is used to achieve ADRC mainly controller parameters self-tuning. The immune ADRC designed can make full use of the characteristics of immune, and can give full play to the effect of control and observation of ADRC. Simulation results show the interference resistance and adaptability of the immune ADRC.