Undisturbed switching control of fuel flow-rate for a high-speed heat-airflow wind tunnel

Abstract

According to the requirements of a high-speed heat-airflow wind tunnel experimental system, a fuel supply system based on variable frequency control technology and proportional throttle valve is designed. The mathematical model of the fuel supply system under the mode of the proportional throttle valve control and the variable frequency pump control is established. Because the fuel supply system has a pure time delay and the change of working conditions can cause the problem of time-variant parameters, a fuzzy proportion integration differentiation control strategy with Smith predictor is proposed. In addition, switching between the pump control mode and the valve control mode will bring disturbances, so two undisturbed switching methods are designed. The simulation and experimental results show that the proposed control strategy can overcome effects of the pure time delay and obtain a satisfactory control performance. The two undisturbed switching control methods designed in this paper can achieve the undisturbed switching of the fuel flow-rate control.