【作者】 何谦；

【导师】 刘忠；

【作者基本信息】 湖南师范大学 ， 电路与系统， 2008， 硕士

【摘要】 传统的液压同步系统无论是开环系统还是闭环系统均存在明显的不足:开环系统成本低但控制精度也不高;闭环系统由于是基于伺服阀或比例阀构建,成本高且难以实现直接数字化控制。以高速开关阀为代表的数字阀,以其方便与计算机直接接口、高可靠性、高性价比等突出优势,给电液控制技术的发展注入了新的活力。本文首先对比分析了不同类型的液压同步控制系统的优点和不足,并在此基础上提出了基于高速开关阀设计液压同步控制系统的必要性和可行性。然后结合高速开关阀自身的特点,提出了三类共5种同步控制回路的设计方案,并对它们各自的优缺点进行了比较和说明,最终选定两种最具可行性和性价比的方案展开研究。接着对高速开关阀直接控制及高速开关阀先导控制的两种液压同步控制回路建立了相应的数学模型,并选择直接控制的方案进行了动态仿真研究,进一步论证了该方案的可行性。最后,针对直接控制系统仿真过程中暴露的问题,引入模糊自适应PID的复合控制策略,设计了相应的同步控制器,综合改善了系统的可控性,为实现高精度的液压同步控制提供了理论支持和技术保证。更多还原

【Abstract】 The traditional hydraulic synchronous system, either the open-loop system or the close-loop system, there are some obvious disadvantages. The cost of the open-loop is low, but its control precision is also not high; the structure of the close-loop is based on servo valve or proportional valve, so not only the cost is high but also the digital control is hard to realize. The digital valve represented by high speed on-off valve, is very significant to the development of the electro-hydraulic control technology, because it possesses lots of prominent advantages such as interacting with computer conveniently and high reliability.Firstly, the thesis analyses the advantages and disadvantage of different types hydraulic synchronous control systems, then discusses the necessity and feasibility of designing the hydraulic synchronous control system based on high speed on-off valve. Secondly, the thesis puts forward five schemes of the synchronous control system, which is based on the characteristics of the high speed on-off valve. The advantages and disadvantages of different schemes are compared and illuminated. The most feasible two schemes are chosen to be studied at last. One of them is the high speed on-off valve works directly, and the other is that the high speed on-off valve works as a pilot valve. The corresponding mathematical models are established after researching on them. And the dynamic simulation of the scheme is chosen to be studied. It can prove the feasibility of this scheme is better. Lastly, in order to overcoming the problems of the system, the compound control strategy based on fuzzy self-adaptive PID is introduced. The synchronous controller is designed. It can improve the controllability of the system and offers the theoretical aegis and technological guarantee to the realization of high precision in the hydraulic synchronous control.更多还原