【作者】 陈莹；

【导师】 魏建华；

【作者基本信息】 浙江大学 ， 机械电子工程， 2013， 硕士

【摘要】 在许多热成型压机加工过程中,滑块平行度是决定加工成型质量的关键因素。如何在特大型热成型压机大台面尺寸,大质量负载条件下保持滑块的高平行精度是热成型压机制造中的一个难题。本文据此提出了一种多级复合--解耦的控制方法：首先,电液比例变量泵,比例调速阀和比例伺服阀三种控制执行器组成了容积--节流复合控制,各控制执行控制器增益和响应相配合,实现了速度的大范围初步调节、小范围精准调节；然后三种控制执行器将速度控制与平行控制解耦,简化了平行控制系统控制器。此外,鉴于特大型热成型压机工作缸和管道的行程长、容积大的特点,提出了油液弹性压缩量补偿的控制方法。经实践验证,该控制方法解决了特大型热成型压机滑块平行控制的难题。有关章节内容分述如下：第一章介绍了液压机滑块平行控制系统的研究现状,对本课题的研究背景、意义以及主要研究内容作了阐述。第二章综合分析了特大型热成型压机滑块平行的特性,并在此基础上设计了适合该系统的液压动力系统、电力动力控制系统以及电液控制系统。第三章建立了特大型热成型压机滑块平行控制系统的数学模型,先从工作缸和回程缸的数学模型入手,建立了各种阀控缸模型,然后建立了滑块运动的整体模型,并化简得到滑块运动状态微分方程的矩阵表达式。第四章针对特大型热成型压机滑块平行控制系统的特点,提出了合适的控制策略,在此基础上设计了相应的控制器,并对滑块平行控制系统进行了仿真研究,初步验证了所设计的方案。第五章主要对所设计滑块平行控制系统进行了实验验证和比较。第六章总结了本课题所做的一些工作以及不足,对特大型热成型压机滑块平行控制系统未来需要进行的研究进行了展望。更多还原

【Abstract】 In many thermoforming pressing processes, the slider’s parallelism of thermoforming press is the key factor of the shaping quality. And it shall be more critical to guarantee the slider’s parallelism during the oversized pressing process with large workbench and massive working load. In this paper, a multi-level compound-decoupling control method was introduced based on this topic:Firstly, the three controllers (electro-hydraulic proportional variable pump, proportional press reducing valve and proportional servo pump) combined together and worked with the volume-throttling compound control method, and the gains and responses of all three controllers were cooperating with each other in order to make the pressing speed having a wide range of preliminary adjustment and a small range of the precise adjustment. Then the speed control and the parallel control were decoupled by the three controllers, so that the controller of parallel control system could be simplified. In addition, a control method for compensating the fluid elastic compression was introduced due to the large volume of the hydraulic cylinder and long length of the pipes in super large thermoforming press. After being approved by practice, this control method can meet the requirements of controlling the slider’s parallelism for thermoforming pressing process.The summary of each chapter can be found as below:In chapter one, the current research status of the control system for the slider’s parallelism of oversized thermoforming press was introduced, and the background, meaning and main contents of this research as well.In chapter two, analyzed the characteristics of slider’s parallelism of the oversized thermoforming press. Based on this, hydraulic power system, electric power system and electro-hydraulic control system were designed specifically for this system.In chapter three, the mathematical models of the slider’s parallelism control system were established. First of all, the mathematical model of working cylinders and kicker cylinders were established, and the next were all kinds of valve controlling cylinders’ models, and then the overall model of the slider sliding movement. At the end, the overall model was simplified to get matrix expression of the state differential equations.In chapter four, an appropriate control strategy was applied specifically to match the control system’s characteristics of the slider’s parallelism for oversized thermoforming press. Based on it, the controller was designed and the system was simulated to validate the control strategy.In chapter five, the tests were carried out with comparable results, in order to validate this newly designed slider’s parallelism control system.In chapter six, summarized the conclusion of this paper especially the lack of this research, and prospected the development of the slider’s parallelism control system for oversized thermoforming press.更多还原