| With the rapid development and wide application of large space building, some large space building fire issues, such as safety, fire control, fire fighting, have become more important cosmopolitan research topics in fire science and technology field for researchers. However, because of the poor equipment and conditions, the studies on the large space building fire technology mainly depend on the computer simulation rather than the entity fire model. As a crucial large space fire research instrument during the China's'Eleventh Five-Year Plan', a large space fire simulation&detection platform was developed to conduct large space building fire research based on entity fire model under the support of the National Science and Technology Support Program. The vertical-lifting platform is a large squared cone, double-layered grid structure with about75ton weight,33m length and33m width. The synchronous motion control and the precise positioning of the large platform in the vertical range from3to24m are key issues of the instrument. Considering some characteristics of the large space fire simulation&detection platform, such as large spatial span, heavy and unbalanced load, long stroke and large deformation, an electro-hydraulic synchronization driving system for the large space fire simulation&detection platform is designed and developed by integrating mechanical transmission, electro-hydraulic control, system simulation, intelligent control and other related theories and techniques in the dissertation. The driving principle, control method and some other related technical issues in the electro-hydraulic synchronization driving system are detailedly presented through both the theoretical analysis and the experimental studies. Results show that the high-precision synchronous lifting control for the platform in the large spatial span can be achieved successfully. The main contents of the dissertation are as follows:In the first chapter, starting with the large space building fire safety problems, the present automatic fire detection and alarm techniques for the large space building are discussed. The significance of the large space fire simulation and detection platform for fire research is demonstrated. Then the current application and research progress about some key technologies in the large vertical-lifting system such as electro-hydraulic synchronization motion control are described. Finally, the main research topics and the significance of this dissertation are summarized briefly.Chapter â…¡, considering the characteristics of the large space fire simulation&detection platform, such as large spatial span, heavy and unbalanced load, long stroke and large deformation, the numbers of the supporting point and the layout of the suspension system for the platform are optimized in ANSYS, and a new electro-hydraulic synchronization driving principle, namely, a driving principle with three machinery-counterweights and three plunger-cylinders, is brought forward. Meanwhile, the mechanical structures of the electro-hydraulic synchronization driving system are designed and studied detailedly, the platform's overall driving structure is proposed. Finally, the principle and integration design for three-cylinder electro-hydraulic synchronization driving system, the monitoring and the control system are presented.Chapter III, a nonlinear mathematical model of the three-plunger-cylinder electro-hydraulic synchronization driving system for the large space fire simulation&detection platform is established based on the mathematical model of the valve-controlled plunger-cylinder mechanism. Meanwhile, a simulation model of the two-plunger-cylinder electro-hydraulic synchronization control system is built in AMESim.Thenvarious parameters affecting synchronous control accuracy are analyzed in AMESim. The simulation results show that it is necessary to study the synchronization strategy for the three-plunger-cylinder electro-hydraulic synchronization driving system of the large space fire simulation&detection platform.In chapter IV, based on the studies on the model reference adaptive control theory and fuzzy logic control theory, an intelligent adaptive synchronization strategy for the electro-hydraulic driving system of the large space fire simulation&detection platform---fuzzy adaptive eletro-hydraulic synchronization strategy on the basis of ideal reference model is proposed to achieve the synchronous motion of the three cylinders. The adaptive controller is designed based on fuzzy control logic theory to make each cylinder track the high-precision real-time dynamic and steady-state output of the same reference model. Thereby, the synchronous motion control performance of the three cylinders is greatly improved. Then, with the AMESim/Simulink co-simulation, the comparison between fuzzy model reference adaptive synchronization control strategy and PID control strategy is implemented in the simulation. Simulation results verify that the proposed controller has a satisfactory static and dynamic performance and robustness.In Chapter V, the development for the PLC control system and the man-machine interface software based on WinCC for the electro-hydraulic synchronization driving system of the large space fire simulation&detection platform are introduced firstly. Then, the comparison between the conventional PID control strategy and model reference fuzzy adaptive electro-hydraulic synchronization control strategy are carried out based on the electro-hydraulic synchronization driving system in the experiment. The experimental results verify the rationality, reliability and practice of the driving principle and structure proposed in the dissertation. Meanwhile, the adaptability and robustness of the proposed control method are also verified. The preliminary application of this fire research platform is presented.Chapter â…¥, main research work and the innovation of the dissertation are summarized and future research work is prospected.
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