【作者】 李大川；

【导师】 潘峥嵘；

【作者基本信息】 兰州理工大学 ， 控制理论与控制工程， 2010， 硕士

【摘要】 我国的水资源比较匮乏,但由于长期以来供水系统的自动化程度一直落后于西方,再加上供水设备和管网比较陈旧,造成了大量的水资源浪费,因此提高供水系统的自动化程度,节约有限的水资源成为时代发展的重要课题。基于变频技术的恒压供水系统不仅能够更好的保持水压的恒定,而其还能节约能源。因此,对其研究具有极大的理论和现实意义。本文在分析港口恒压供水系统原理的基础上,对其控制系统的方案进行了设计。同时介绍了系统中的同步切换技术以及GPRS远程通信技术。由于供水系统的被控对象是一个高阶次、大滞后、参数时变的非线性系统,无法建立精确的数学模型,同时当需水量变化较大时,水泵电机由变频供电向工频供电切换过程中会产生过电压和过电流冲击,因此本文采用无模型自适应控制算法和锁相环同步切换技术相结合组成双闭环控制,来实现港口供水系统压力的稳定。为便于远程控制,利用GPRS通信技术代替传统的电缆及数传电台作为通信媒介,从而提高整个控制系统的自动化程度。理论分析和仿真验证了本控制策略的有效性。在理论分析的基础上,进行了港口恒压供水控制系统的软硬件设计。在硬件上分别进行了控制电路、信号采集电路、同步切换电路、GPRS通信模块电路等的设计,在软件上采用模块化的思想,分别给出了恒压供水、GPRS通信、上位机监控、同步切换等主要工作功能模块的详细流程图。更多还原

【Abstract】 China’s water resources are very scarce, because of the automation of water supply system has long been lagging behind the West,water supply equipment and pipelines are relatively obsolete, a lot of water is wasted. Thereby increasing the automation of water supply systems and saving limited water resources has become an important topic of the times. Water supply system with constant pressure based on conversion technology is not only better able to maintain a constant pressure, but it also can save energy. Therefore, the research has great theoretical and practical significance. This paper analyzes the principle of the port water supply system,and we design its control system. At the same time,we introduced the simultaneous switching technology and the GPRS remote communications technology in this system.As the controlled object of port water supply system is a high time, time delay, parameter time-varying nonlinear systems, we can not establish a precise mathematical model. At the same time when the water requirement is large, the process of the frequency power supply switch will produce over-voltage and over-current shocks,therefore,this paper adopts dual-close-loop control by combining the no model adaptive control algorithm and switching technique. We can achieve stability on port pressure water supply system. In order to facilitate remote control, we use GPRS communication technology instead of traditional cable and data radio as a medium of communication to enhance the automation of the whole control system. Theoretical analysis and simulation results show that this control strategy can not only improve the stability and reliability of the port pressure water supply system,but also can achieve frequency conversion. Based on theoretical analysis, we design the hardware and software of port water supply system with constant pressure. We design the control circuit, the signal acquisition circuit, synchronous switch circuit, GPRS communication module circuit in the hardware. In the software we adapt modular idea, and we give the main function modules of the detailed flow chart,including the part of constant pressure water supply, GPRS communications, supervisory control and synchronous switching.更多还原