Study On Control Techniques Of Pressure Field In The Multi-Parameter Combined Environment Testing Device

In this thesis, the author made research on the pressure control system in the multi-parameter combined environment testing device which was associating with the National High Technology Research and Development Program of China (" 863 Program), "Study on Multi-parameter-Integrated and Accelerated Reliability Testing Environment for the Components in the Airspace Craft".In chapter 1, the destination and significance of the thesis was presented. First, the definition and significance of environmental simulation test was introduced. Then, the domestic and foreign research status and developing trends on such research was presented. Again, the domestic and foreign research status and developing trends on the techniques of pressure control was introduced. At last, the main research content and aim of the dissertation was pointed out.In chapter 2, the coupling mechanism of pressure and other main parameters in multi-parameter combined environment testing device was studied. First, the coupling mechanism of pressure field and centrifugal force was researched and the distribution of pressure field under different centrifugal acceleration was simulated.Then, the coupling mechanism of pressure field and temperature field was studied and the distribution of pressure field under different temperature was simulated At last, the design of the control system was proposed according to the results of related simulation.In chapter 3, the general structure of the pressure control system in the multi-parameter combined environment testing device was presented. First, the function and qualification of the pressure control system was pointed out. Then, the gas circuit structure of the pressure control system was designed. At last, the electrical control scheme of the pressure control system was expounded.In chapter 4, the circuit design technique in the pressure control system was studied. First, the control circuit structure of the pressure control system was presented. Then, the key circuit module design technique in the pressure control system was analyzed. At last, the anti-disturbance measures which were used to improve reliability of the pressure control system were discussed.In chapter 5, the software design technique in the pressure control system was researched. First, the software requirement of the system was analyzed. Then, the control network design of the system software was discussed. Again, the pressure control algorithm based on PWM was introduced. At last, the software design technique of the pressure control system was analyzed.In chapter 6, some experiments were taken on the pressure control system which was successfully developed. First, some experiments were taken to detect the function and the main control indictors of the pressure control system. Then, other experiments were taken to detect the property of this system under the effect of multi-parameter combined environment, which included the centrifugal and the pressure combined environment, the temperature and the pressure combined environment, and five parameters combined environment. The experiment results indicate that the pressure control system can meet design requirements.In chapter 7, the achievement of the dissertation was briefly summarized and the further research work which needs to be done was expected.