| Because of the solid rocket ramjets were more and more widely used in aircraft, the study of flow control technology in gas generator is prompted. And as for the requirement of the integral solid rocket ramjet is increasing, gas flow control technology and control methods is becoming the focus of the current national study. The gas flow control technology of integral solid rocket ramjet was investigated in this paper.Firstly, according to the index, two sets of different actuators were designed respectively: actuator of pneumatic needle-type gas control valve, and actuator of dynamoelectric gate-type gas control valve. The mathematical models of two actuators were established. And the actuators were tested in dynamic response and static track. Test results showed that the performance parameters of two sets of the actuator could meet the requirements basically.Secondly, the working characteristic of the gas generator was analyzed. Static model and dynamic model of the adjustment system were established. After the linearization, Model was a non-minimum phase system with anti-regulation characteristics. The reasons of anti-regulation phenomenon were analyzed in step adjustment status and dynamic adjustment status based on non-linear model. The results showed that the anti-regulation was a kind of inevitable phenomenon that was associated with the process of gas flow regulation. The effects of burning rate exponent, free volume of gas generator, gas generator throat area, and valve actuation speed on anti-regulation duration and anti-regulation extent were analyzed.Thirdly, three different kinds of control modes are discussed: throat area control system, pressure of gas generator control system, transition process design considering the phenomenon of inverse response. And the control methods of gas generator were researched and designed in these three aspects. The control method based on the limit of inverse response was researched for the throat control system. The speed of system response was improved based on limit of anti-regulation extent with this control method. In the view of the pressure control system characteristics, linear ADRC is designed. Pressure was rapid control without overshoot in long time work and different adjusting range with linear ADRC. On the basis of the pressure control system, the fuzzy differential tracker was used for the transition function of the system. The anti-regulation extent was reduced, and the effect to speed of response was small.The gas regulation system was been experiments in cold and hot state. In the cold experiment, feasibility of pressure control method was verified. And the effect of control signal rate on the phenomenon of inverse response was research. In the hot experiment, the stability of the actuator was been verified. The experiment results reflected the gas regulation system characteristics in a certain extent. The effect of mechanical dead zone for the pressure control system was analyzed.At last, variable flow ducted rocket in long time work was analyzed and its mathematical model was established. In the view of variable parameter and anti-regulation characteristics of system, the generalized predictive control algorithm was designed. The results of simulation showed that compared with the traditional controller, the generalized predictive control could effectively reduce the phenomenon of inverse response of the system. The overshoot of the system and unstable phenomenon were reduced, and control precision of system was improved with the control algorithm... |
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