Application of Active Disturbance Rejection Control with Known Improved Bouc-Wen Modeling Items in Microflow Control

For micro-newton-scale thrust systems in drag-free satellite, cold gas thrust and field ionization thrust usually require fast and stable flow control. In order to achieve high precision, low noise and fast response thrust control, stable and continuous flow control is the premise. At present, piezoelectric proportional valve composed of piezoelectric actuator and needle valve is widely used in flow control. However, the nonlinear characteristics of piezoelectric proportional valve such as hysteresis and creep are the main factors of internal disturbance in flow control system. Therefore, an active disturbance rejection control algorithm based on the improved Bouc-Wen (B-W) model is proposed in this paper. Firstly, the theoretical model and the phenomenological B-W model are combined to establish the improved B-W model, and then the model is applied to the active disturbance rejection control (ADRC) algorithm with known modeling corrections. Finally, simulation experiments are carried out. The simulation results show that the proposed method can effectively compensate and suppress nonlinear disturbances such as hysteresis and creep of piezoelectric proportional valve, thus improving the accuracy of flow control.