[通信电子设计-精品]基于CAN总线的楼宇温度控制系统设计-外文原文及翻译.doc

1、 密 级分类号编 号成 绩本科生毕业设计 (论文)外 文 翻 译原 文 标 题Distributed Building Temperature Control System Ba PLC OVER ETHERNET/IPBased on CAN Bus译 文 标 题基于CAN总线的楼宇温度控制系统设计作者所在系别电子工程系作者所在专业电子信息工程作者所在班级作 者 姓 名作 者 学 号指导教师姓名指导教师职称教授完 成 时 间2009年12月 译文标题基于CAN总线的楼宇温度控制系统设计原文标题Distributed Building Temperature Control System Ba

2、sed on CAN Bus作 者WAN ZHONG,etc译 名 国 籍中国原文出处Journal of Zhejiang Wanli University基于CAN总线的楼宇温度控制系统设计万忠，谢志波摘要文章提出了一种基于CAN总线的楼宇温度控制系统，并给出了系统硬件和软件的设计方案，分析了控制台和分布在楼宇中的控制节点之间的通信问题，从而实现对楼字温度实时检测，并对异常情况进行报警和控制，试验表明该系统可靠，能实现节能目的关键词：温度控制 CAN总线 节能1.引言随着人们生活水平的提高，电力工业每年都会面临用电最多的季节：电力迎峰度夏2003年以来，我国供电形势从缓和转为全面吃紧，建筑

3、节能成为热点问题，其中空调节能是最突出的公共建筑的空调是高能耗的源头之一以北京为例，公共建筑尽管只占全市民用建筑总面积的54，但公共建筑全年总耗电量却达到33亿千瓦，接近所有居民生活用电的一半1据初步了解，北京市的公共建筑普遍存在着30-50的节能空间2一种最重要的方法是通过对楼宇的内部温度进行实时检测从而控制楼宇空调。2.系统结构原理与硬件设计图1 系统硬件结构图不同的楼宇，其内部空间分布和结构是不同的为实现系统的构建，笔者提出一种基于SJAl000的CAN通信平台来实现各节点的可靠通信；在此基础上，由主控制器实现对各检测节点的温度设定，实时检测整幢楼宇温度，并由LCD显示结果，对异常情况进

4、行语音报警和控制，以实现节能目的系统的设计目的是为了测量和控制分布在一栋建筑物内各个房间的温度，而测温和控制节点是分散的，所以要通过CAN总线实现控制台和分布在建筑物的各个部分的控制节点相连，每个控制节点可以控制多个房间的温度系统结构如图l所示21 主控台和硬件设计图2 控制台硬件结构图控制台是AT89C52单片机，为主控制器，连接报警模块、存储模块、时钟日历电路和人机接口电路，其结构如图2所示控制节点也由单片机控制，连接温度检测模块和CAN总线接口模块。该系统采用AT89S52，这是一节低功耗芯片，该芯片是由ATMEL公司生产的，有4 KB的系统内可编程（ISP）的FLASH存储器。使用AT

5、89S52作为系统的主控制器，现场编程调试和系统的功能变化非常方便灵活。在系统正常工作时，控制台通过CAN总线发出一个明确的控制温度值分布在建筑中的指定节点。该节点接收控制台的命令，通过分布在每个房间1 - Wire总线读取温度探测器DS18B20的温度值，通过CAN总线传送每个房间的温度数据和房间号码到控制台。根据由主机控制在每个房间空调气门系统接收的一定的温度值。经过数据接收发送到节点，控制台通过CAN总线在接收到控制节点发来的数据后，通过12C总线读取实时时钟，13历芯图2控制台硬件结构图片PCF8563的时间，并作相应处理，当房间的温度超过设定值时，发出报警信号，同时将房间号、时间、报

6、警原因等信息传送至LCD进行显示每个房间报警温度值通过键盘输入模块确定，控制台在内存中输入和存储过程中相应的值。22 CAN总线接口设计CAN总线通信的波特率高达1Mbs，最远通信距离可达lOkm；CAN总线通信采用短帧结构，使得数据传输的时间短，受干扰的概率低，并且CAN总线协议有良好的检错措施，因此CAN总线通信的可靠性较高，可以应用于有较强干扰的环境CAN总线定义网络中的每一节点对应一地址，在实际应用中，CAN总线最多可挂110个节点基于CAN总线通信对于传送的信息帧可以设定不同的优先级，并通过总线仲裁机制使高优先级的信息能够被优先、及时地传送，保证了更重要的信息能及时地被传送，从而增加

7、了CAN总线通信的实时性CAN总线接口采用PHILIPS公司生产的CAN控制器SJAl000和CAN驱动器PCA82C250SJAl000是集成的独立CAN控制器(与PHILIPS早期的CAN控制器PCA82C200完全兼容)，负责完成CAN总线通信协议的物理层和数据链路层的功能阁SJAl000内置控制寄存器、命令寄存器、状态寄存器、中断寄存器和收、发寄存器等，单片机就是通过读写这些寄存器来实现对SJAl000的控制；芯片的TXO、RXO引脚用于与CAN总线收发驱动芯片相连PCA82C250是专门用于CAN总线收发驱动的8脚芯片，TXD、RXD引脚分别接收和发送CAN总线控制器的信号；双绞线(

8、同轴电缆)传输介质分别接至CANH、CANL引脚考虑到使用现场可能有各种各样的干扰，在CAN控制器和驱动器之间增加高速光耦隔离器件(6N137) 623节点硬件设计控制节点主要包括CAN总线接口、控制模块和温度传感器DSl8820，系统结构如图3所示图3 控制节点的硬件结构设计图Dallas半导体公司最新单线数字温度传感器DSl8820是一款体积更小、适用电压更宽、更经济的数字化温度传感器现场温度直接以“一线总线”的数字方式传输，大大提高了系统的抗干扰性，并且支持3-55V的电压范围，使系统设计更灵活、方便DSl8820内部ROM中的64位序列号是出厂前用激光光刻写好的，它可以看作是该DSl8

9、820的地址序列码64位光刻ROM的排列是：开始8位是产品类型标号，DSl8820的产品系列码固定为28H；接着的48位是该DSl8820自身的序列号，而这48位序列号为全球唯一的，最后8位是前面56位的循环冗余校验码利用DSl8820 ROM中的序列号作为1一Wire网络中的地址，唯一标识一个传感器，这样就可以实现一根总线上挂接多个DSl8820的目的根据Dallas公司提供的DSl8820资料，每根单线总线上最多可以挂248个lWire器件tTl但在试验中发现并非如此当一根单线总线上所挂的DSl8820超过8个时，就需要解决控制节点的单片机对单线总线的驱动问题，否则单片机就不能正确实现对D

10、Sl8820的读写同时，连接DSl8820的总线电缆也是有长度限制的，当采用普通信号电缆作为总线传输测温数据时，长度超过50m时，读取的测温数据就会发生错误当将总线电缆改为双绞线带屏蔽电缆时，正常通信距离可达150m因此该系统每个控制节点一根单线总线最多接8个DSl8820，这样设计的目的既能保证单片机对总线的驱动，同时也能满足通信距离不超过150m，从而实现系统的稳定运行3.系统软件设计系统构成包括控制台和控制节点两部分，因此软件设计主要包括控制台程序设计和节点程序设计两个部分，控制台程序结构如图4所示31控制台软件设计控制台程序从大模块上划分为初始化和主调度两块初始化部分仅在上电启动或复位

11、时运行一次；主调度主要包括CAN信息帧处理、键盘按键处理、显示处理和报警、数据和时间处理、中断控制等部分.图4 控制台程序结构图主调度主要负责协调和管理各个子任务的运行，主调度巡查各个子任务激活条件，当激活子任务的事件发生时，将激活该子任务运行，否则跳过这一子任务；如果有多个激活条件出现，主调度负责仲裁系统初始化的功能是建立系统使用环境，包括CAN总线接口初始化、时钟芯片初始化等CAN信息帧处理模块主要实现利用CAN总线实现控制台和各控制节点之间的通信键盘按键处理模块主要用来实现键盘的输入按键的识别及相关处理显示处理和报警模块则实现根据数据时间处理模块处理的结果传送至LCD显示，并控制报警系统

12、数据和时间处理模块主要是实现对从CAN总线接口接受来的数据进行处理并保存到AT24C128中，并根据系统时间和温度报警设定值做相应的处理最后的中断控制模块用实现CAN总线接以口实时通信和键盘按键实时响应32控制节点软件设计控制节点的主要功能是和控制台通信，检测分布在每个房问中的DSl8820的温度值，如果超过限定值，则向控制台报警并控制该房间的空调风门同时通过CAN总线向控制台报告房间号和温度值根据DSl8820的通信协议，节点单片机控制DSl8820完成温度转换必须经过三个步骤：每一次读写之前都要对DSl8820进行复位，复位成功后发送条ROM指令，最后发送RAM指令嘲，这样才能对DSl88

13、20进行预定的操作复位要求单片机将数据线下拉500s，然后释放，DSl8820收到信号后等待1660s左右，后发出60240s的存在低脉冲，单片机收到此信号表示复位成功当单片机执行传感器DS18B20测量温度程序的流程时，它会发出温度变换命令。单片机会等待传感器DS18B20变为低信号。一旦与传感器DS18B20连接的总线不好或者损坏，单片机将无法读取低信号，并进入无限循环等待。因此，我们通过单片机的定时器中断系统来解决这个的问题。4. 结论实地测试后，该系统可以有效的实现楼宇温度检测与控制.并且该系统可以应用到其他设备的检测和控制，以实现楼宇智能化管理。虽然CAN总线是一种用于分布式工业控制

14、的串行通信网络，但该系统还可以广泛应用于其他需要实时多点测量和控制的地区。指 导 教 师 评 语 外文翻译成绩：指导教师签字： 年 月 日注：1。 指导教师对译文进行评阅时应注意以下几个方面：翻译的外文文献与毕业设计（论文）的主题是否高度相关，并作为外文参考文献列入毕业设计（论文）的参考文献；翻译的外文文献字数是否达到规定数量（3 000字以上）；译文语言是否准确、通顺、具有参考价值。2。 外文原文应以附件的方式置于译文之后。Distributed Building Temperature Control System Based on CAN BusAbstractThis paper pr

15、oposed a kind of distributed buildingtemperature control system based on CAN Bus, and has produced the system of hardware structure design, the software design, can examine the building temperature and control the exceptional on the real-time, be indicated through experiment that system is reliable

16、and save energy. Key-Words:- temperature control；CAN Bus；energy saving 1 Introduction Gradually climbs along with the temperature, electric power industry welcomed has used electricity once a year most seasons: The electric power welcomes a peak summer. Since 2003, the power supplied has become more

17、 and more serious in china. And more and more people appeal for building energy conservation. Air conditionings energy conservation is one of the most important components of building energy conservation1. Many public buildings air conditioning is one of highest energy consumption sources in China.

18、Take Beijing as the example, in 2005, although the Beijing large-scale public building only accounts for the whole city civil construction total area 5.4%, but whole year the total power consumption actually achieved 3.3 billion kilowatts2, approach all inhabitants to live use electricity one half,

19、according to the preliminary understanding, Beijings public building generally can achieved to energy saving for 30% to 50%through technology transformation, One of most important method is through the real-time examination building interior temperature to control building in air conditioning. 2 The

20、 principle of system structure and hardware design Regarding the different building, its internal room distributes and constructs is different, in order to realize the system construct conveniently, the system uses the distributional structure, Based on the SJA1000 CAN communications platform in ord

21、er to realize various pitch points reliable communication; In this foundation, the console set each pitch point temperature value setting for every room, and realize the entire building temperature real-time examination, by the LCD demonstration examination result, the unusual situation is reported

22、by the warning through speech Property by the signal and controlled through the gate of air conditionings system , realization energy conservation goal. The system design goal is measure and control temperature in a building each room, because measured the temperate point and control point is disper

23、sion, therefore the system uses the distributional structure, The console is connected each part of control pitch point distributing in the building through the CAN Bus. System structure diagram like figure 1 shows2.1 The console hardware design The AT89C52 MCU is the primarily controller in console

24、, It connects with the warning module, the memory module, the clock/calendar electric circuit and the keyboard module. its structure drawing see Figure 2. The control pitch point also is controlled by the MCU, connected temperature examination module and the CAN Bus interface module. The system has

25、used the AT89S52, it is a section low power chip that is produced by ATMEL Corporation, has 4 KB in-system programmable (ISP) FLASH memory integrated. The scene programming debugging and the system function changing is much conveniently flexible, using AT89S52 to take the system the master controlle

26、r. When system normal work. The console send a definite control temperature value to a designate pitch point Distributed in the building through the CAN Bus. The pitch point receive the consoles orders and read the temperature detector DS18B20 temperature value distributed in each room through 1-Wir

27、e bus, transmits each room temperature data and the number of room to the console through the CAN Bus. According to the definite temperature value which receives from console control the air gate of air-conditioning system in each room. After receive the data a pitch point send to, the console reads

28、 the time from real-time clock/calendar chip PCF8563 through the I2C Bus, with the data which just received store to the memory AT24C128, then process each room temperature value. When the value achieve the data which is established from keyboard in advance, the console output warring to the alarm c

29、ircuit on reports the alarm. Meanwhile the room number, the time and the temperature value delivers the LED display circuit to display. Every room alarm temperature value is established through the keyboard input module, the console process value and stores in the memory corresponding the input. 2.2

30、 The CAN Bus interface design The CAN Bus corresponds high as 1 Mb/ s, the most long-distance range may reach 10 km; The CAN Bus corresponds using the short frame structure, spends the data transmission time shortly, so the probability which disturbed is low, and the CAN Bus has good error detecting

31、 measures, therefore its reliability is high. In the CAN Bus network each pitch point has an address, any pitch point theoretically can be increased, deleted in the network based on CAN Bus. In the practical application, the CAN Bus network most access 110 pitch points. The network communication met

32、hod may for the point-to-point way or for the broadcast way, May be the single host way or many hosts way. Therefore, the CAN Bus correspondence has the suitable flexibility. The transmission correspondence information frame can establish the different priority based on the CAN Bus and higher priori

33、ty information frame can be transmitted first and promptly through the Bus information arbitration mechanism. This increase more important information can promptly transmit, increase the CAN Bus correspondence timeliness. The CAN Bus network suits the commercial processing monitor equipments by its

34、remarkable characteristic, the inexpensive price, the extremely high reliability and the nimble structure. The pitch point core component is CAN controller SJA1000 which is PHILIPS Corporation produced and CAN driver PCA82C2503. SJA1000 is the integrated independent CAN controller (is completely com

35、patible with PHILIPS early CAN controller PCA82C200). It responsibly completes the CAN Bus correspondence protocol function of the physical layer and the data link layer. SJA1000 internal has the control register, orders the register, the condition register, the interrupt register and receives, send

36、s the register and so on, the MCU realizes SJA1000 control through read-write these registers. The Chip of SJA1000 pins TX0, TX1, RX0, RX1 use to connect with the CAN Bus. PCA82C250 is 8 feet chip specially uses to drive receiving and dispatching in the CAN Bus. The SJA1000 pins of TXD, RXD separate

37、ly receive and send signal after the drive; The twisted pair wire (coaxial cable) transmits the medium separately to meet to the chip of PCA82C250 pins CANH, CANL. Considered the scene has various disturbance, the high speed light isolation components (6N137) are added between the CAN controller SJA

38、1000 and the PCA82C2504. 2.3 The pitch point hardware design The pitch point mainly includes the CAN Bus interface, the control module of the air gate of air-conditioning system and temperature sensor DS18B20, the system structure like figure 3 shows. The DS18B20 is DALLAS Semiconductor Corporations

39、 newest 1-Wire Bus digital temperature sensor5. Its volume is smaller, suitable voltage is wider, and more economical. 1-Wire Bus is unique moreover the economical characteristic. The user can set up the sensor network with ease. The 1-Wire Bus directly transmits scene digital temperature and greatl

40、y enhanced the system anti-disturbance ability. It supports the voltage of 3V5.5V. So the system can be designed nimbly and conveniently. The ROM in the DS18B20 has stored 64 bits serial number .It was written with the laser before leaved the plants, it can be regarded as each DS18B20 address serial

41、 number. The 64 bits serial number arrangement is: the first 8 bits is the product type marking, the DS18B20 product series code is fixed is 28H; After that 48 bits are this DS18B20 own sequence numbers, and these 48 sequences number is only one in the whole world, finally 8 bits are the front 56 cy

42、clical redundancy check code. So use the 64 bits serial number we can divide each DS18B20,and we can meets many temperature sensors of DS18B20 on one1-Wire Bus. According to DALLAS Semiconductor Corporations material, on each 1-Wire Bus can connect mostly 248 1 - WIRE components 5. But we discovered

43、. It was not so in practical. When one 1-Wire Bus meets more than 8 DS18B20 sensors, the system must to solve the question that MCU drive 1-Wire Bus, otherwise the MCU cannot correctly read and write to DS18B20 through 1-Wire Bus. Simultaneously the fastest 1-Wire Bus length which connect DS18B20 se

44、nsor in system is also limited. In full-scale test, when uses the ordinary signal electric cable as the 1-Wire Bus to measure, the length surpasses 50m, it take mistake that the MCU reads DS18B20 sensor through the bus. When the bus is changed the twisted pair cable with belt shielded, the correctly

45、 communication distance can reach 150m. Therefore in this system, each pitch point we most meets 8 DS18B20 sensors in one 1-Wire bus, and the bus is no more than 150m with the twisted pair cable with belt shielded. The system design like this is make sure the MCU can drive the 1-Wire bus, and can be

46、 satisfy with the communication and stability. 3 The system software design In this system, the software design mainly includes two parts : The console software design and pitch point software designs. The figure 4 shows console software structure. 3.1 The console software design The console softwar

47、e divides for the initialization module and the host scheduling program module In general. The initialization module is executed only power on or reset. The host scheduling program module includes CAN information frame processing processor, key processing processor, the LCD processing and warring pr

48、ocessor, and so on data and time processing processor, interrupt control processor. The host scheduling program module is responsible to manage the processors running. When the event occurred, the processors do it will be activated and executed, otherwise the processor will be jumped. The system initialization module establishes the systems operating environment, including CAN interface initialization, clock chip initialization and so