【作者】 熊运塔；

【导师】 王划一；

【作者基本信息】 山东大学 ， 控制理论与控制工程， 2009， 硕士

【摘要】 社会的发展和人类生活水平的不断提高,使人类对居住环境的要求也越来越高,因此中央空调系统的应用也越来越广泛。中央空调系统改善了人们的居住环境,但同时也消耗了大量的能源。对于中央空调控制系统,目前的中央空调控制技术还以分散控制为主,每个控制器只能监控其所控制的中央空调机组的状态,这不仅不利于整个系统的智能管理,而且浪费能源。有少数中央空调控制器生产厂商进行了少量中央空调集中化,网络化控制的尝试,但采用的技术比较落后,大多数通信距离较短,所能集中监控的中央空调的数目也少。近几年网络技术越来越成熟,网络安全、实时性、可靠性进一步提高,这使我们已经逐渐能够将网络技术应用到控制领域;同时,单片机技术发展讯速,很多单片机已经具有多功能、高速度、低功耗、低价格、大存储容量和强I/O功能等特点,因此,我们完全可以设计出基于单片机的低成本远程控制系统,并把它应用于中央空调集中监控系统。本课题的主要任务是研制具有远程通讯功能的中央空调集中监控系统。它能通过Internet将数据转发给控制中心,使得控制中心能对楼宇内部甚至几栋楼宇的所有中央空调机组的运行状态进行监视与控制。通过这种新型的中央空调网络集中监控,能够提高中央空调机组的使用效率,使得楼宇内的所有中央空调,达到统一控制、统一管理、高效节能的目的。系统总体采用多级分布式控制结构,在与互联网连接的中间站中,基于ATmega128与Enc28j60设计了以太网传输方案,通过在ATmega128上移值TCP/IP协议,系统能够与远程电脑通讯,实现中央空调的远程实时监控;楼宇内扩展RS485总线,进行数据的传输,可以有效节约成本与减少设计难度。末端实现具体房间的空调机组的温度控制,并有RS485接口上传数据与接受上层传来的控制命令。远程电脑客户端利用可视化的编程工具Visual Basic及其Winsock控件开发网络应用程序,通过以太网实现了多栋楼宇的中央空调远程监控。文中概述了现阶段楼宇中央空调远程控制的情况,详细讨论了整个系统的设计方案选择与确定,介绍了其结构与功能,并分章节说明了各个部分的硬件设计方法与软件设计思路。硬件各部分分别以AVR高档MEGA系列单片机为核心,扩展以太网接口和RS485总线接口进行数据传输,配以部分按键显示模块及其它控制模块,实现适当的控制与显示。软件设计则重点介绍了在ATmega128上基于ENC28J60的Microchip TCP/IP协议栈移值实现方法、RS485通信程序设计及一部分键盘显示程序设计。论文中给出了大部分电路图与一些关键源程序或流程图,并对系统的可靠性与抗干扰性设计作了部分介绍。上位机部分详细说明了VB使用ADO对象访问ACCESS数据库的连接方法与应用,介绍了Winsock控件的各种重要属性与使用方法。系统完成后应用于实践工程,运行稳定可靠。该设计系统具有实现方法简单、成本较低、扩展性好等特点,具有一定的实用性和推广价值。文中最后对课题进行了总结,并指出了未来系统需要增强和改进的方向。更多还原

【Abstract】 With the development of national economy and constant improvement of people’s life, people’s demands on the environment become higher and higher, so the application of central air conditioner grows to be abroad. The central air conditioner system improves people’s living condition, but it also uses up a lot of energy sources. Actually, most of central air conditioners are controlled separately, each controller can only monitor and control one air conditioner’s status, that not only makes against the intellective management, but also wastes of much energy. A few of controller product manufacturers of central air control conditioner tried to use network to control the whole system concentratively, however, mostly, the technology they applied was behindhand, the communication length was not very long, and the number of terminals they controlled was limited.In recent years, the technology of network has become more mature, its security, and reliability have future improved, so we can apply network technology to the control field gradually. In addition, the single-chip technology also develops rapidly, many single chips have the characteristics of multifunction, high speed, low power, low price, big memory and strong I/O, all that make us be able to design low cost remote control system based on single chips, and then apply it to central air conditioner.The main task of this thesis is to develop a concentrative control system about central air conditioner with long-range communication function, which can communicate with control center via Internet, and then we can monitor and control all terminals’ status in one building or several buildings. The concentrative control and management can improve the efficiency of central air conditioner, and reduce energy consummation. The whole system uses multi-level distributed control architecture.In stage which connects to Internet, we develop an Ethernet transmit scheme based on ATmegal28 and Enc28j60. It transplants the Microchip TCP/IP protocol stack into ATmega128 to implement remote real time supervise and control by communicating with remote computer.The system expands RS485 bus for data transmission in building to save the cost and reduce the difficulty to design. The terminals aim to control the room’s temperature directly, they transmit status data to its upper layer and receive control command by RS485 interface. We make use of visualized programming tools Visual Basic and its Winsock control to develop network application program for the client in remote computer. The paper summarizes the situation of remote control system about central air conditioner in brief, introduces its architectures and functions, and discusses the choice of the whole system scheme in detail, including transmission bus in building, remote transmission method, remote communication mode. The thesis concretely describes the hardware design method and the soft design ideal of each part. Hardware parts design the circuit based on AVR top grade MEGA series single chip, then expand Ethernet interface and RS485 bus interface to transmit data, with some key-display module and other control modules. The soft sections emphasize the method of embedding the TCP/IP protocol stack into ATmega128, design of RS485 communication program, and some keyboard display program. The thesis offers a majority of circuit diagram and some key source program or flow chart, the reliability and the capability of anti-jamming are also described in simple. The client segment describes how to use ADO object to connect and access ACCESS database at length, it also introduces some important properties of Winsock and its technique, so as to develop network program.The application shows that this system runs stably and accurately. The technology and methods adopted in the system are practical and worthy of using abroad, with the characteristics of low cost, good expansibility. Finally, the subject is briefly summaried, and some remarks on further improvement to the system are also presented.更多还原