【作者】 黎职富；

【导师】 彭楚武；

【作者基本信息】 湖南大学 ， 控制理论与控制工程， 2008， 硕士

【摘要】 电液比例控制技术是工程机械的核心技术之一,经过六十多年的发展,它由一项单一的技术,形成了目前机电液一体化、智能化、信息化的综合自动化系统。在我国由于起步晚,技术水平低,汽车起重机生产企业往往需要从国外引进电液比例控制系统核心控制器,以提升自身产品的竞争力。但是进口的控制器产品一方面价格偏高,造成汽车起重机整车成本高昂;另一方面它是通用产品,难以适应国内的汽车起重机的某些特殊作业环境,以致故障不断。因此,自主研发设计汽车起重机电液比例控制系统及其核心控制器,已成为国内汽车起重机生产企业的当务之急。本文密切结合湖南省科技攻关重点项目进行研究,围绕“汽车起重机电液比例控制系统”的开发做了大量的工作。论文综述了电液比例控制技术的发展历程及发展方向。在分析汽车起重机液传动系统数学模型的基础上,针对该模型的非线性、大滞后及不确定性特点,本文构建了一种新型的控制器—模糊神经网络PID控制器,将模糊神经网络与常规PID控制器相结合,调整PID控制器的三个参数,实现了对液压马达转速的精确控制。另外,汽车起重机的机械结构决定了其电液比例控制系统只能采用主从式双CPU结构,在复杂的施工环境下,节点之间可靠通讯成了迫切需要解决的问题,针对这一问题,论文在对比各种工业控制组网方式的基础上,提出了利用CAN总线实现主从节点的通信方案。并在ARM硬件平台和μC/OS-Ⅱ微内核软件平台上实现了CAN总线应用层协议—CANopen协议。最后,本文针对无位置反馈的电磁比例阀,设计了高频PWM波驱动模块,使线圈平均电流和颤振信号独立可调,并实现了线圈电流的闭环控制,可以很大程度上解决没有位移反馈带来了定位精度不够、响应速度减慢的问题,更重要的是,该驱动模块能够有效降低摩擦,减少电磁铁的磁滞现象。核心控制器的实验表明,本文设计的汽车起重机电液比例控制系统已实现设计需求,具有稳定可靠、操作方便等优点,表明本文所研发成果的有效性和实用价值。更多还原

【Abstract】 Electro-hydraulic proportional control technology is critic to construction mechanism including auto crane. With rapid development of Chinese fundamental constructions, more and more auto cranes are needed. It provides a good opportunity of expanding this market and making fortune for both abroad and civil auto crane manufacturer. But there are some difficulties to compete with overseas counterparts for civil manufacturer. One reason is that poor of technical level, most civil manufacturers’products are based on the imported electro-hydraulic proportional controller which is act as the core, as a result, the cost become higher and lost the advantage of lower cost. The other lies in the imported electro-hydraulic controller itself. Being a general product, the imported control doesn’t work well in particular working conditions in China. Based on above two points, developing electro-hydraulic proportional controller of having independent intellectual property is now urgent to civil auto crane manufacturer.Combined with a significant project of Hunan province, the application and research of electro-hydraulic proportional control system base on engineering machinery has been put forward. Firstly the development history and trend of electro-hydraulic control systems are introduced. Based on the modeling of auto crane hydraulic system, to solve the non-linearity, hysteresis and time-variation of the system, a novel control algorithm-fuzzy neural network PID is put forward and the closed-loop control of hydraulic motor is implemented, the PID control parameters are adjusted by the fuzzy neural network. Secondly, kinds of field buses applied to industrial control network are studied, can bus is finally selected to guarantee the stable and real-time communication between master and slave nodes, furthermore, based on the ARM hardware platform andμC/OS-Ⅱmicro kernel platform, the CANopen protocol implemented. Lastly, the paper design a high frequency PWM driver for electro-hydraulic solenoid to implement the closed-loop control of coil current, the current of coil and the frequency of dither signal can be tuned separately, even more important, magnetic hysteresis problem is solved.The experiment of central controller states that embedded electro-hydraulic proportional control system described in the paper has reached the design demand with the advantage of stability, security and easy to handle. It also states the the research is of validity and practicability.更多还原