Active disturbance rejection controller design for distributed parameter systems

A control problem of dynamic processes described by partial differential equations (PDE's) is proposed and studied in this paper. They are linear distributed parameter models. The inputs of the models discussed are position-independent. As is known to all, distributed parameter systems always demand high tracking precision and good stability. However, it is difficult for classical approaches to achieve a high performance in disturbance rejection. Active disturbance rejection controller (ADRC) has great ability of resisting disturbance and could meet the demand of fast-track. In order to ensure the system output converging to the reference value, ADRC controller is designed. Extended state observer (ESO) is a key part of ADRC and a reasonable designed ESO can improve the performance of ADRC. In this study, the Gaussian approximation is used to design a higher order ESO to eliminate the model uncertainty and total disturbance. Simulation results indicate that ADRC controller is superior to traditional PI controller both in terms of set-point tracking and disturbance rejection.