【www.gbppp.com--新秀美文】
Design of PLC Timer System Based on FPGA
Li Kejian, Liu Tong, Cai Qizhong
School of Electronic Information and Control Eng
Guangxi University of Technology
Liuzhou Guangxi China
lijian6262@I26.com; srk04 I26@I26. com;
cqiqzh@163. com
Abstract-Aiming at the design of the small PLC timer system,based on the analysis of operational characteristics of PLC timer and the process of PLC user timer program and the data transmission requirements of PLC user program execution module and the timer, a method which applies the FPGA Parallel
algorithm to designing small PLC timer system , is presented. The timer system is composed of clock generator unit, timing unit, timing control unit and the chip select circuit. While the timer runs at the speed of lms timed pulse, the operation of timer is translated into the operation of RAM memory cell which is made up of FPGA. That makes user can operate on RAM memory cell instead of the timer, and it just take up a few execution time of PLC user program. This paper introduces the theory and structure of the FPGA timer system, the state
transition diagram of timer control module, the timing diagram of user program execution module operating on timer, finally take an experiment and gives analysis of the results.
Keywords-PLe timer system;FPGA;dynamic in/ormation code;paralle/ operation;state transition;
1. INTRODUCTION
Timer is an important soft-devices of Programmable Logic Controller (PLC)
[1 ][2], which is used as the time relay of relay control system. Timer is widely used in automatic control system, such as timing sampling, timing inspection, timing scanning, etc. The implementations of timing are non-programmable hardware timing, software timing and programmable hardware timing. PLC
provides hundreds to thousands of timers [3] [4], and their timing unit typically has three kinds like 1 ms, 10ms and lOOms. If the timer were implemented all by hardware design, it would be relatively simple but would take up a lot of
hardware resources. Therefore, it has great practical significance to
implemented this large number of timer functions reasonably. This paper
proposes a theory using the FPGA Parallel algorithm to design a small PLC timer system. This timer system is composed of clock generator unit, timing unit, timing control unit and the chip select circuit. Each timing unit is made up of 3 bit dynamic information data and 28 bit timing parameters data. Several
memory cells will constitute one timing unit. While operating at the speed of 1 ms timing pulse, timer control module judges the state of the 3 bit dynamic information code of timing unit and operates the timing process. At the same time, the timer control module will scan the status of user program execution module operating timer, that makes user program execution module operates on RAM memory cell instead of the timer itself and it just take up a little the
executive time of PLC user program. This paper introduces the theory and
structure of the FPGA timer system, the state transition diagram of timer control module, the timing diagram of user program execution module operating on timer, finally take an experiment and gives analysis of the results.
II. SYSTEM DESIGN
A. The operation on timer by PLC user program execution module
The numbers of different types PLC timer are different and neither the types of timers. The small PLC timer has three kinds of working state. The first state is when the input conditions are not satisfied, the soft component of timer coil is in power-down state and the corresponding contact is disconnected. The second state is when the input conditions are satisfied, timer works in a timing state and the corresponding contact is disconnected. The third state is when the timing is completed, the input conditions are still satisfied and the corresponding contact is closed. The PLC timer timing value T = timing resolution factor multiple timing constant K. In programming applications, once the timer is selected, the timing
resolution factor is subsequently identified as Ims, 10ms or lOOms. Figure 1 is a ladder program diagram of timer TO. Timer TO is one soft component which made up of coil and its status is "1" when power is on and "O"when power is off. When timing is completed, the soft component of timer TO is power on, its
contact closes and its status becomes "1 ", when timing is not completed, the soft component of timer TO is power off, its contact breaks and its status stays "0". If the timing resolution factor of TO is 1 OOms and K is 100 then the time value T = lOOms x 100 = lOs.
An example of the timing process is shown in Fig.1.
When the input signal XO is connected, the coil of timer TO is driven. The timer counts the lOOms pulses, at the same time, the counting value is continually
compared with the preset value. When these two values are equal, the contact of TO will be connected. The function is, once the timing coils is power on, its
contacts will be closed after lOs time-delay. When the input signal XO is
disconnected, the coil will be reset and power off, the counter value and the output of contact TO will both be reset immediately.
B. The data transmission of PLe user program execution module and timer In order to transfer one timer data between the PLC user program execution module and timer in one time, a 32-bit data line is adopted, shown in Figure 2. the operations of User program execution module on timer are OUT Txxx, Kxxx, and the corresponding state of timer's input conditions. Txxx is the address, Kxxx is the timing data. Then the information that PLC user program execution
module exports to the timer system mainly contain the timing data, the timing
address, the status of soft coil and the flag status of timer(being used or not). The
information that the timer system exports to PLC user program execution
module mainly contain the timing address, the completing status of the process of timing, the control information of message read or written, etc.
Timer unit is independently addressed through the address bus and chip
select signals, and processes the timing operation on selected unit address. By mapping the addresses, the timer number and the unit address are one-one correspondent. The directly mapped addresses while compiling the instructions are shown in Table I.
C. The design of timer control logic
According to the operational principle of timer, the timer system based on
FPGA is designed to consists of four modules, that are clock generator unit,
timing unit, timing control unit and chip select circuit [5]. The block diagram of
timer system is shown in Figure 2.【plc英文参考文献】
The clock generator unit generates required reference clock cycle Ims. elkin is the input signal from the main clock that generated by the 50MHz system
frequency; elk_lms is the 1 ms periodic signal output. At each rising edge, it will trigger one counting operation on timer unit by the timer control unit.
Timing control unit (Timer controller) is the core component of the whole
timer design. Its main function are detecting the usage status of timer i, and the operation status of timer i and the completing status of timing. If the timer i is in process and the timing hasn't completed, this timer will be minus by I.
When timing completed for the first time, the information that closing the
contact is sent to the soft component area of corresponding position. When timing completed for the 2nd and even the Nth time, the information won't be
sent to the soft component area of corresponding Bit processing storage unit. When timer is power off for the first time, the information that breaking the contact is sent to the soft component area of corresponding Bit processing
storage unit. When timer is power off for the 2nd and even the Nth time, the information won't be sent to the soft component area of corresponding position. Timing control unit does not involve the operation of instruction decoding.
The timer unit carries out the cycle counting in the Ims reference clock after the timer unit has been given an initial value. Timing control unit processes state
transitions in accordance with the elkin frequency. In other words, timing
自动化专业本科毕业设计英文翻译
学院(部)：
专业班级：
学生姓名：
指导教师：
年 月 日
Programmable Logic Controller
ONE：PLC overview
Programmable controller is the first in the late 1960s in the United States, then called PLC programmable logic controller (Programmable Logic Controller) is used to replace relays. For the implementation of the logical judgment, timing, sequence number, and other control functions. The concept is presented PLC General Motors Corporation. PLC and the basic design is the computer functional improvements, flexible, generic and other advantages and relay control system simple and easy to operate, such as the advantages of cheap prices combined controller hardware is standard and overall. According to the practical application of target software in order to control the content of the user procedures memory controller, the controller and connecting the accused convenient target.
In the mid-1970s, the PLC has been widely used as a central
processing unit microprocessor, import export module and the external circuits are used, large-scale integrated circuits even when the Plc is no longer the only logical (IC) judgment functions also have data processing, PID conditioning and data communications functions. International Electro technical Commission (IEC) standards promulgated
programmable controller for programmable controller draft made the following definition : programmable controller is a digital electronic computers operating system, specifically for applications in the industrial design environment. It used programmable memory, used to implement logic in their internal storage operations, sequence control, timing, counting and arithmetic operations, such as operating instructions, and through digital and analog input and output, the control of various types of machinery or production processes. Programmable controller and related peripherals, and industrial control systems easily linked to form a whole, to expand its functional design. Programmable controller for the user, is a non-contact equipment, the procedures can be changed to
change production processes. The programmable controller has become a powerful tool for factory automation, widely popular replication.
Programmable controller is user-oriented industries dedicated control computer, with many distinctive features.
First, high reliability, anti-interference capability;
Second，programming visual, simple;
Third, adaptability good;
Fourth functional improvements, strong functional interface.
TWO：History of PLC
Programmable Logic Controllers (PLC), a computing device【plc英文参考文献】
invented by Richard E. Morley in 1968, have been widely used in industry including manufacturing systems, transportation systems, chemical process facilities, and many others. At that time, the PLC replaced the hardwired logic with soft-wired logic or so-called relay ladder logic (RLL), a programming language visually resembling the hardwired logic, and reduced thereby the configuration time from 6 months down to 6 days [Moody and Morley, 1999].
Although PC based control has started to come into place, PLC based control will remain the technique to which the majority of
industrial applications will adhere due to its higher performance, lower price, and superior reliability in harsh environments. Moreover, according to a study on the PLC market of Frost and Sullivan [1995], an increase of the annual sales volume to 15 million PLC per year with the hardware value of more than 8 billion US dollars has been predicted, though the prices of computing hardware is steadily dropping. The inventor of the PLC, Richard E Morley, fairly considers the PLC market as a 5-billion industry at the present time.
Though PLCs are widely used in industrial practice, the
programming of PLC based control systems is still very much relying on trial-and-error. Alike software engineering, PLC software design is facing the software dilemma or crisis in a similar way. Morley himself emphasized this aspect most forcefully by indicating
If houses were built like software projects, a single woodpecker could destroy civilization.”
Particularly, practical problems in PLC programming are to
eliminate software bugs and to reduce the maintenance costs of old ladder
logic programs. Though the hardware costs of PLC are dropping
continuously, reducing the scan time of the ladder logic is still an issue in industry so that low-cost PLC can be used.
In general, the productivity in generating PLC is far behind
compared to other domains, for instance, VLSI design, where efficient computer aided design tools are in practice. Existent software engineering methodologies are not necessarily applicable to the PLC based software design because PLC-programming requires a simultaneous consideration of hardware and software. The software design becomes, thereby, more and more the major cost driver. In many industrial design projects, more than of the manpower allocated for the control system design and installation is scheduled for testing and debugging PLC programs.
In addition, current PLC based control systems are not properly designed to support the growing demand for flexibility and
reconfigurability of manufacturing systems. A further problem, impelling the need for a systematic design methodology, is the increasing software complexity in large-scale projects.
The objective of this thesis is to develop a systematic software design methodology for PLC operated automation systems. The design methodology involves high-level description based on state transition models that treat automation control systems as discrete event systems, a stepwise design process, and set of design rules providing guidance and measurements to achieve a successful design. The tangible outcome of this research is to find a way to reduce the uncertainty in managing the control software development process, that is, reducing programming and debugging time and their variation, increasing flexibility of the
automation systems, and enabling software reusability through modularity. The goal is to overcome shortcomings of current programming strategies that are based on the experience of the individual software developer. Three：now of PLC
From the structure is divided into fixed PLC and Module PLC, the two kinds of PLC including CPU board, I/O board, display panel, memory block, power, these elements into a do not remove overall. Module type PLC including CPU module, I/O modules, memory, the
power modules, bottom or a frame, these modules can be according to certain rules combination configuration.
In the user view, a detailed analysis of the CPU's internal
unnecessary, but working mechanism of every part of the circuit. The CPU control works, by it reads CPU instruction, interprets the instruction and executes instructions. But the pace of work by shock signal control.
Unit work under the controller command used in a digital or logic operations.In computing and storage register of computation result, it is also among the controller command and work. CPU speed and memory capacity is the important parameters fot PLC . its determines the PLC speed of work, IO PLC number and software capacity, so limits to control size.
Central Processing Unit (CPU) is the brain of a PLC controller. CPU itself is usually one of the microcontrollers. Aforetime these were 8-bit microcontrollers such as 8051, and now these are 16-and 32-bit
microcontrollers. Unspoken rule is that you’ll find mostly Hitachi and Fujicu microcontrollers in PLC controllers by Japanese makers, Siemens in European controllers, and Motorola microcontrollers in American ones. CPU also takes care of communication, interconnectedness among other parts of PLC controllers, program execution, memory operation, overseeing input and setting up of an output.
System memory (today mostly implemented in FLASH technology) is used by a PLC for a process control system. Aside form. this operating system it also contains a user program translated foram ladder diagram to a binary form. FLASH memory contents can be changed only in case where user program is being changed. PLC controllers were used earlier instead of PLASH memory and have had EPROM memory instead of FLASH memory which had to be erased with UV lamp and programmed on programmers. With the use of FLASH technology this process was greatly shortened. Reprogramming a program memory is done through a serial cable in a program for application development.
User memory is divided into blocks having special functions. Some parts of a memory are used for storing input and output status. The real status of an input is stored either as “1”or as “0”in a specific memory bit/
参考文献
[1]周万珍,高鸿斌(第一版).PLC分析与设计应用[M]. 北京:北京机械工业出版社,2004:32
[2]韩安荣.通用变频器及其应用(第二版)[M].北京:北京机械工业出版社,2000:36
[3]姚厚伟.变频器供水系统中的应用与节能[M]. 北京：航空航天大学出版社,2003:42
[4]厉无咎.变频调速恒压供水系统[M]. 北京：电子工业出版社,2005:28
[5]张燕宾.循环水系统的变频调速[M]. 北京:北京机械工业出版社,2002:45
[6]彭小红,刘国东.基于PLC的变频调速恒压供水系统的设计[M]. 北京：人民邮电出版 社,2004:56
[7]卢建勤.PLC及变频器在恒压变频供水系统中的应用[M].北京：电子工业出版社,2005:4
[8]许建平,焦建雷.PLC在变频调速恒压供水系统中的应用[J].西安科技学院学报,2004,(1):32-39
[9]贺玲芳.基于PLC控制的全自动变频恒压供水系统[J].西安科技学院学报.2007,(9):16-26
[10]马云峰,徐春岭.PLC的PID功能在恒压供水系统中的应用[J].西安交通大学报,2006,(6):36-38
[11]郑兆生,张伟,郑新志.PLC及变频器恒压供水控制系统设计[J],山东轻工业学院学报,2007,3:123-138
[12]邵裕森,戴先中.过程控制工程[M].北京:机械工业出版社,2007,3:166-169
[13]杨东平.变频调速恒压供水系统综述[J],南宁职业技术学院学报,2004,4:38-45
[14]俊赞,李雄松,尹元日.PLC在恒压供水控制系统中的应用[J],电机电器技术,1999,3:45-48
[15]崔金贵.变频调速恒压供水在建筑给水应用的理论探讨[J],兰州铁道学院学报,2000,1:84-88
1
PLC论文中英文对照资料外文翻译文献
外文资料:
PLC technique discussion and future development
Along with the development of the ages, the technique that is nowadays is also gradually perfect, the competition plays more more strong; the operation that list depends the artificial has already can't satisfied with the current manufacturing industry foreground, also can't guarantee the request of the higher quantity and high new the image of the technique business enterprise.
The people see in produce practice, automate brought the tremendous convenience and the product quantities for people up of assurance, also eased the personnel's labor strength, reduce the establishment on the personnel. The target control of the hard realization in many complicated production lines, whole and excellent turn, the best decision etc., well-trained operation work, technical personnel or expert, governor but can judge and operate easily, can acquire the satisfied result. The research target of the artificial intelligence makes use of the calculator exactly to carry out, imitate these intelligences behavior, moderating the work through person's brain and calculators, with the mode that person's machine combine, for resolve the very complicated problem to look for the best path
We come in sight of the control that links after the electric appliances in various situation, that is already the that time generation past, now of after use in the mold a perhaps simple equipments of grass-roots control that the electric appliances can do for the low level only;And the PLC emergence also became the epoch-making topic, adding the vivid software control through a very and stable hardware, making the automation head for the new high tide.
The PLC biggest characteristics lie in: The electrical engineering teacher already no longer electric hardware up too many calculationses of cost, as long as order the importation that the button switch or the importation of the sensors order to link the PLC up can solve problem, pass to output to order the conjunction contact machine or control the start equipments of the
big power after the electric appliances, but the exportation equipments direct conjunction of the small power can.
PLC internal containment have the CPU of the CPU, and take to have an I/ O for expand of exterior to connect a people's address and saving machine three big pieces to constitute, CPU core is from an or many is tired to add the machine to constitute, mathematics that they have the logic operation ability, and can read the procedure save the contents of the machine to drive the homologous saving machine and I/ Os to connect after pass the calculation; The I/ O add inner part is tired the input and output system of the machine and exterior link, and deposit the related data into the procedure saving machine or data saving machine; The saving machine can deposit the data that the I/ O input in the saving machine, and in work adjusting to become tired to add the machine and I/ Os to connect, saving machine separately saving machine RAM of the procedure saving machine ROM and datas, the ROM can can do deposit of the data permanence in the saving machine, but RAM only for the CPU computes the temporary calculation usage of hour of buffer space.
The PLC anti- interference is very and excellent, our root need not concern its service life and the work situation bad, these all problems have already no longer become the topic that we fail, but stay to our is a concern to come to internal resources of make use of the PLC to strengthen the control ability of the equipments for us, make our equipments more gentle. PLC language is not we imagine of edit collected materials the language or language of Cs to carry on weaving the distance, but the trapezoid diagram that the adoption is original after the electric appliances to control, make the electrical engineering teacher while weaving to write the procedure very easy comprehended the PLC language, and a lot of non- electricity professional also very quickly know and go deep into to the PLC.
Is PLC one of the advantage above and only, this is also one part that the people comprehend more and easily, in a lot of equipmentses, the people have already no longer hoped to see too many control buttons, they damage not only and easily and produce the artificial error easiest, small is not a main error perhaps you can still accept; But lead even is a fatal error greatly is what we can't is tolerant of. New technique always for bringing more safe and convenient operation for us, make we a lot of problems for face on sweep but light, do you understand the HMI? Says the HMI here you basically not clear what it is, also have no interest understanding, change one inside text explains it into the touch to hold or man-machine interface you knew, it combines with the PLC to our larger space.
HMI the control not only only is reduced the control press button, increase the vivid of the control, more main of it is can sequence of, and at can the change data input to output the
feedback with data, control in the temperature curve of imitate but also can keep the manifestation of view to come out. And can write the function help procedure through a plait to provide the help of various what lies in one's power, the one who make operate reduces the otiose error. Currently the HMI factory is also more and more, the function is also more and more strong, the price is also more and more low, the noodles of the usage are wide more and more. The HMI foreground can say that think ° to be good very.
At a lot of situations, the list is is a smooth movement that can't guarantee the equipments by the control of the single machine, but pass the information exchanges of the equipments and equipments to attain the result that we want. For example fore pack and the examination of the empress work preface, we will arrive wrapping information feedback to examine the place, and examine the information of the place to also want the feedback to packing. Pass the information share thus to make both the chain connect, becoming a total body, the match of your that thus make is more close, at each other attain to reflect the result that mutually flick. The PLC correspondence has already come more more body now its value, at the PLC and correspondence between PLCs, can pass the communication of the information and the share of the datas to guarantee that of the equipments moderates mutually, the result that arrive already to repair with each other. Data conversion the adoption RS232 between PLC connect to come to the transmission data, but the RS232 pick up a people and can guarantee 10 meters only of deliver the distance, if in the distance of 1000 meters we can pass the RS485 to carry on the correspondence, the longer distance can pass the MODEL only to carry on deliver. The PLC data transmission is just to be called a form to it in a piece of and continuous address that the data of the inner part delivers the other party, we, the PLC of the other party passes to read data in the watch to carry on the operation. If the data that data in the watch is a to establish generally, that is just the general data transmission, for example today of oil price rise, I want to deliver the price of the oil price to lose the oil ally on board, that is the share of the data; But take data in the watch for an instruction procedure that controls the PLC, that had the difficulty very much, for example you have to control one pedestal robot to press the action work that you imagine, you will draw up for it the form that a procedure combine with the data sends out to pass by.
The form that information transport contain single work, the half a work and the difference of a workses .The meaning of the single work also is to say both, a can send out only, but a can receive only, for example a spy he can receive the designation of the superior only, but can't give the superior reply; A work of half is also 2 and can can send out similar to accept the data, but can't send out and accept at the same time, for example when you make a phone【plc英文参考文献】
call is to can't answer the phone, the other party also; But whole pair works is both can send out and accept the data, and can send out and accept at the same time. Be like the Internet is a typical example.
The process that information transport also has synchronous and different step cent: The data line and the clock lines are synchronous when synchronous meaning lie in sending out the data, is also the data signal and the clock signals to be carry on by the CPU to send out at the same time, this needs to all want the specialized clock signal each other to carry on the transmission and connect to send, and is constrained, the characteristics of this kind of method lies in its speed very quick, but correspond work time of take up the CPU and also want to be long oppositely, at the same time the technique difficulty also very big. Its request lies in can'ting have an error margins in a datas deliver, otherwise the whole piece according to compare the occurrence mistake, this on the hardware is a bigger difficulty. Applied more and more extensive in some appropriative equipmentses, be like the appropriative medical treatment equipments, the numerical signal equipments...etc., in compare the one data deliver, its result is very good.
And the different step is an application the most extensive, this receive benefit in it of technique difficulty is opposite and want to be small, at the same time not need to prepare the specialized clock signal, its characteristics to lie in, its data is partition, the long-lost send out and accept, be the CPU is too busy of time can grind to a stop sex to work, also reduced the difficulty on the hardware, the data throw to lose at the same time opposite want to be little, we can pass the examination of the data to observe whether the data that we send out has the mistake or not, be like strange accidentally the method, tired addition and eight efficacies method etc., can use to helps whether the data that we examine to send out have or not the mistake occurrence, pass the feedback to carry on the discriminator.
A line of transmission of the information contain a string of and combine the cent of: The usual PLC is 8 machines, certainly also having 16 machines. We can be an at the time of sending out the data a send out to the other party, also can be 88 send out the data to the other party, an and 8 differentiationses are also the as that we say to send out the data and combine sends out the data. A speed is more and slowly, but as long as 2 or three lines can solve problem, and can use the telephone line to carry on the long range control. But combine the oscular transmission speed is very quick of, it is a string of oscular of 25600%, occupy the advantage in the short distance, the in view of the fact TTL electricity is even, being limited by the scope of one meter generally, it combine unwell used for the data transmission of the long pull, thus the cost is too expensive.
Under a lot of circumstances we are total to like to adopt the string to combine the conversion chip to carry on deliver, under this kind of circumstance not need us to carry on to depositted the machine to establish too and complicatedly, but carry on the data exchanges through the data transmission instruction directly, but is not a very viable way in the correspondence, because the PLC of the other party must has been wait for your data exportation at the time of sending out the data, it can't do other works.
When you are reading the book, you hear someone knock on door, you stop to start up of affair, open the door and combine to continue with the one who knock on door a dialogue, the telephone of this time rang, you signal hint to connect a telephone, after connecting the telephone through, return overdo come together knock on door to have a conversation, after dialogue complete, you continue again to see your book, this kind of circumstance we are called the interruption to it, it has the authority, also having sex of have the initiative, the PLC had such function .Its characteristics lie in us and may meet the urgently abrupt affairs in the operation process of the equipments, we want to stop to start immediately up of work, the whereabouts manages the more important affair, this kind of circumstance is we usually meet of, PLC while carry out urgent mission, total will keep the current appearance first, for example the address of the procedure, CPU of tired add the machine data etc., be like to to stick down which the book that we see is when we open the door the page or simply make a mark, because we treat and would still need to continue immediately after book of see the behind. The CPU always does the affair that should do according to our will, but your mistake of give it an affair, it also would be same to do, this we must notice.
The interruption is not only a, sometimes existing jointly with the hour several inside break, break off to have the preferred Class, they will carry out the interruption of the higher Class according to person's request. This kind of breaks off the medium interruption to also became to break off the set. The Class that certainly break off is relevant according to various resources of CPU with internal PLC, also following a heap of capacity size of also relevant fasten.
The contents that break off has a lot of kinds, for example the exterior break off, correspondence in of send out and accept the interruption and settle and the clock that count break off, still have the WDT to reset the interruption etc., they enriched the CPU to respond to the category while handle various business. Speak thus perhaps you can't comprehend the internal structure and operation orders of the interruption completely also, we do a very small example to explain.
2016自动化专业本科毕业设计开题报告(模板)
课题名称：基于gprs的远程监控系统
学生姓名：武广东
专业名称：机械及自动化
1、课题的目的及研究意义随着计算机技术的发展，尤其是internet技术广泛深入到人们生活的各个方面，使人们的生活发生了深刻的变化，从工控领域来讲，由于需要监控的区域广、监控的对象种类繁多，因而需要花费大量的人力、物力和财力进行设备的维护，而且存在许多条件恶劣、人们不易到达或不能时刻停留的地方偶尔采集1些现场数据，如果进行大量的布线工作则是不经济、不合理的，这就推动了无线通信的技术在远程监控领域的发展。
而随着plc应用的迅猛发展，各种高级空盒子策略不得不面对不同的对象在大跨距分散地点下的远程控制应用，如何实现大范围分布式应用中各种现场数据传输处理及远程控制，远程维护等就是很现实的问题，这其中的前提之1就是各中数据包de远程传输。
以前，有的plc应用系统中采用了无线数传电台通信来达到远程控制plc的目的，但是这种方案仍然存在1些缺陷，主要就是其分布范围仍然较为有限，而且随着通信距离的增加，其可靠性受到很大影响。目前最新应用趋势是将plc空盒子系统与现有gprs无线通信网络技术集成，通过gprs网络通信技术，可以实现全国，甚至全球范围内的数据超远程可靠传输，进而达到数据远程分析处理，远程控制的目的。
2、本课题的主要研究内容 (1)现场控制/采集点：现场监控点由plc实现自动控制，并采集相关信息，通过rs232或rs485接口与gprsdtu终端相连，plc采集到的设备信息通过gprsdtu终端对数据进行处理、协议封装后发送到gprs无限网络。
(2)监控中心：a)公网接入方案
服务器采用公网方式接入internet如adsl拨号/电信专线宽带上网等，申请公网固定ip地址;可以实现中小容量的系统应用。
b)专网接入方案
服务器采用省移动通信公司提供的ddn专线，申请配制固定ip地址，与gprs网络相连。由于ddn专线可提供较高的带宽，当现场plc数量增加，中心不用扩容既可满足需求，可实现大容量系统应用。监控中心radius服务器接受到gprs网络传来的数据后进行aaa认证，后传送到监控中心计算机主机，通过系统软件对数控进行还原显示，并进行数据处理，这样进1步增强了系统数据通信安全性能。
(3)gprs移动数据传输网络：
plc采集的数据经gprs网络空中接口功能模块同时对数据进行解码处理，转换成在公网数据传送的格式，通过中国移动的gprs无线数据网络进行传输，最终传送到监控中心ip地址。
3、进度计划xx年12月30前，毕业设计选题;
xx年1月7日学生提交毕业设计的开题报告;
xx年3月5日始，毕业生校外顶岗实习;期间每两周向指导教
师和辅导员分别汇报毕业设计和校外实习的情况;
xx年4月6日毕业生将毕业设计初稿交指导教师审阅;
xx年5月10日，毕业生将毕业设计第2稿交指导教师审阅
xx年6月4日，毕业生返校，带回毕业实习协议书、实习鉴定
(实习单位盖章)及实习总结报告，指导教师审阅论文
xx年6月23，24日毕业答辩。
4、参考资料[1]郑家莉、黄炜主编。片机及嵌入式系统应用。北京：中国轻工业出版社，2016
[2]胡大可主编。sp430系列超低功耗16位单片机原理与应用。北京：北京航空航天大学出版社，2000
[3]李华、李学云主编。代移动通信新技术gprs系统。广州：南理工大学出版社，2001
[4]张雷主编。gprs系列手册。上海，2016
[5]沈建华、杨艳琴、翟骁曙主编。msp430系列16位超低功耗单片机原理与应用。北京：2016
[6]梅丽凤、王艳秋、张军主编。单片机原理及接口-技术。北京：北京清华大学出版社，2016
[7]赵含颖主编。组无线业务(gprs)的技术实现和业务应用的研究。北京：信-息-产-业-部电信传输研究所，2016
[8]蔡悦丹、许少云、甘义成主编。gprs无线数据传输系统的设计与应用[j]。上海：上海交通大学出版社，2016
导师意见：导师签名：xx-xx年xx月xx日
教研室审批意见：
教研室主任签名：xx-xx年xx月xx日
系毕业设计(论文)工作指导委员会审批意见：
系主任签名：xx-xx年xx月xx日
2016毕业设计开题报告模板二 论文题目：新乡信息港
学生姓名：学号：
专业：
指导教师：
年月日开题报告填写要求1、开题报告作为毕业设计(论文)答辩委员会对学生答辩资格审查的依据材料之1、此报告应在指导教师指导下，由学生在毕业设计(论文)工作前期内完成，经指导教师签署意见审查后生效。
2、开题报告内容必须用黑墨水笔工整书写，或按系统1设计的电子文档标准格式打印(外语系网页)，禁止打印在其它纸上后剪贴，完成后应及时交给指导教师签署意见。
3、学生查阅资料的参考文献应在5篇及以上(不包括辞典，手册)，开题报告的字数要在1000字以上。
4、有关年月日等日期的填写，应当按照国标gb/t7408—94《数据元和交换格式，信息交换，日期和时间表示法》规定的要求，1律用阿拉伯数字书写。如"2016年9月26日"或"2016-09-26"。
1、本课题的研究意义 2、本课题的基本内容 3、本课题的重点和难点
4、论文提纲 5、参考文献 6、研究进度 毕业论文开题报告指导教师意见：(对本课题的深度，广度及工作量的意见)
指导教师：
xx-xx年xx月xx日系部审查意见：
系部负责人：xx-x
xx-xx年xx月xx日
2016自动化专业本科毕业设计开题报告(模板) [篇2]院（系） 专 业
设计（论文）题目XZ系列芯模振动制管机芯模制管机
PLC控制系统设计
学 生 姓 名 王碧波 学号 08009418 起 止 日 期设 计 地 点
指 导 教 师
顾 问 教 师
开题日期 2016年 2月25日 江苏华光双顺机械制造有限公司 王晓俊 周杏鹏
2016自动化专业本科毕业设计开题报告(模板) [篇3] 毕业设计题目：双容水箱液位控制系统设计 1.选题依据：1.1课程研究的背景和意义
随着水箱在生活的广泛应用，如居民房顶水箱供水，饮料加工厂的液体存储箱，化工工厂中燃料的调配等都涉及到水箱也为控制问题，如用人工控制，不仅效率低操作繁琐，且易造成空箱，溢水等现象。因此水箱控制越来越重要。
许多公司生产中都会用到水箱系统，它的性能和工作质量的优良不仅对生产有着巨大的影响，而且也关系着生产的安全，在过去，大量的对水箱操作是由人工或者机械系统进行操作的，这样的工作方式带来了很大的弊端，比如水位的控制，时刻监控水箱的环境，夜间的控制等等，操作员稍有疏忽，或者简易的监控器件损坏，将带来无法弥补的损失，更严重的会危及到生产人员的人身安全等，还有控制装置故障多，错误动作多，且只能单独控制，与计算机进行通信较难实现，所以，对水箱控制，如过能够使用精密的而且完全会严格按照生产规定运行的自动化系统，可以最大限度的避免事故的几率，同时也能节省资源并能邮箱提高生产的效率
那么我们再从其他方面考虑，中国是一个资源平穷国家，我国大部分能源需要从其他国家进口。尤其是水资源，中国人均水资源占有仅为世界平均水平的 28%.目前，全国年平均缺水约400亿立方米，2/3的城市不同程度缺水，地下水超采区面积达19万平方公里，水功能区达标率仅42%.水资源的保护已经刻不容缓了，而每年因为水箱的老旧或设备的非智能化，造成数以万吨的水资源浪费。那么就要提高生产技术，积极改革生产工艺，降低单位产品生产的水量，减少生产用水量和工业废水排放量。对于水箱水位的监控以及自动化的引入可以很好的改善补水过多和及时补水的情况，可以很好的节约资源有效的降低成本。
随之而来的是怎样实现水箱的自动化?答案很简单，一块小小的单片机就可以帮助我们解决问题，单片机，又称单片机微型计算机，是一种集成电路芯片。单片机采用超大规模集成电路技术构成一个小而完善的微型计算机系统，单片机以其强大的功能，简单的设计，制造的廉价，支持指令集多，所以应用到众多嵌入式系统开发中。
因此 ,基于单片机的双容水箱设计有很大的实际意义。对于我们的生活与实验研究有很大的促进作用。
1.2发展历史、现状及发展趋势
1.2.1国内外水箱控制的发展：
水箱系统是典型的过程控制实验设备之一，在国内外有很多大学和实验室都已得到广泛地运用。如英国牛津大学、剑桥大学、德国杜伊斯堡大学、韩国首尔大学、中国清华大学、浙江大学、哈尔滨工业大学等高校都引进了水箱控制系统实验装置。它不仅可以作为液位过程控制的实验装置，还可以应用到非线性控制和故障诊断的研究项目中。
在德国杜伊斯堡大学测量与控制系的研究者使用dts200模型成功的测量非线性解耦方法和基于模型的故障诊断方法[6].noura hassan用三容水箱液位控制系统作为实验模型对执行器容错控制的设计进行研究[7];又如r.sehab以双容水箱液位控制系统为研究对象提出来一种用于非线性系统的模糊pi监控器的设计报告[8].又如德州学院机电工程系的金秀慧做了基于mcgs的液位监控系统设计，它是一种基于at89c51单片机的远程液位数据采集监控系统，采用单片机作为控制核心，上位机采用mcgs编写的监控软件，整个系统可以完成液位信号的采集与转换、数据传送和显示、控制等功能[9].
在国内也有许多研究者研究水箱的控制问题，如北方工业大学理学院的安艳伟做了基于单片机的分布式液位控制系统设计，设计了一种基于51单片机为核心多机分布式液位控制系统，由数据采集模块，处理模块和多种通讯平台组成，既满足了测量精度的要求，同时具有较高的可靠性，成本低，控制灵活。又如南京邮电大学的牛标和张代远所做的可监控智能液位控制器系统设计中列举了液位控制系统可以采取的硬件方案以及他们各自的优缺点，采用fpga作为控制器可以实现各自复杂的逻辑功能，规模大，密度高，他将所有芯片集成在一块芯片上，减小了体积，提供稳定性，并且可应用eda软件仿真、调试，易于进行功能扩展[10].
1.2.2水箱控制得发展方向：
液位控制系统一般指工业过程中自动控制系统的被控变量为液位的变化[11].在生产过程中，对液位的相关参数进行控制，使其保持在一定值或一定规律范围内变化， 以保证质量和生产安全，师生产自动进行下去。在此基础上发展起来的单片机综合了计算。
2.研究方案：2.1设计目的
设计双容水箱的水路循环系统，采用simulink对所设计的系统进行仿真分析，确定最佳算法。采用单片机控制器对双容水箱液位进行控制。
2.2本课题主要解决的问题
1.运用单片机作为水箱的控制核心，完成水箱的水位控制、报警和自动切换
2.采用pid串级控制完成双容水箱的控制系统
3.采用汇编语言对系统进行编程
4.采用simulink对设计系统进行仿真
5.写出相应的使用说明、使用效果和改进意见
2.3本课题拟采用研究方法和途径
双容水箱液位控制系统主要由以下几个基本环节组成：控制对象(水箱)。液位测量变送装置、控制器(单片机)、执行器(电动调节阀)、水泵、储水箱。如图1所示。
lt表示液位变送器，水箱流入量和流出量分别为q1和q2,控制的主要目标是维持水箱的液位为其设定值h,即干扰出现时，控制器能迅速做出决策，并使被控量尽快到回到设定值。
3.参考文献：[1] 李峰，胡征，景苏等。 纳米粒子的控制生长和自组装研究进展[j]. 无机化学学报， 2001, 17(3)： 315~324
[2] j.y.li, x.l.chen,h.li. fabrication of zinc oxide nanorods[j]. journal of crystal growth, 2001,233:5~7
[3] 司宗国 谢去病 王群﹒重子湮没快度关联的研究﹒见赵维勤，高崇寿编﹒第五届高能粒子产生和重离子碰撞理论研讨会文集[c],北京：中国高等科学技术中心，1996:105
[4]韩其智 孙洪洲﹒群论[m]﹒北京：北京大学出版社，1987﹒101
学位论文 作者﹒论文题目[d]﹒学士(或硕士、博士)学位论文。 出版地：出版者，出版年份
[5] 陈异。纳米粒子形貌控制研究[d]. 硕士学位论文。 北京：中国科学院， 2002
专利 专利所有者。专利名称[p]. 专利国别：专利号，日期。
[6] 姜锡洲 . 一种温热外敷药制备方案[p]. 中国专利：881056073,1989-07-26.
报纸类 作者。篇名[n].报纸名，出版日期(版次)
2016自动化专业本科毕业设计开题报告(模板) [篇4] 1、本课题的目的及意义，国内外研究现状分析本课题的目的及意义
随着我国经济的快速发展和人民生活水平的不断提高，消费者的观念不断转变，食品健康受到越来越多的关注。在三聚氰胺奶粉事件以后，豆浆变得更受欢迎，成为现代人喜爱的饮品之一。
豆浆的营养价值极高，是一种非常理想的健康饮品。据专家介绍，在豆浆里含有多种优质蛋白、多种维生素、多种人体必须的氨基酸和多种微量元素等。只要坚持饮用，可以提高体质、预防和治疗病症。豆浆中，钙的含量尤其高，比其他任何乳类都丰富，是防治高血脂、高血压、动脉硬化等疾病的理想食品，多喝鲜豆浆可预防老年痴呆症，防治气喘病。豆浆对于贫血病人的调养，比牛奶作用要强，以喝热豆浆的方式补充植物蛋白，可以使人的抗病能力增强，调节中老年妇女内分泌系统，减轻并改善更年期症状，延缓衰老，减少青少年女性面部青春痘、暗疮的发生，使皮肤白皙润泽，还可以达到减肥的功效。春秋饮豆浆，滋阴润燥，调和阴阳;夏饮豆浆，消热防暑，生津解渴;冬饮豆浆，祛寒暖胃，滋养进补。
在高速发展的现代社会，豆浆机使用先进的科学技术做出了
本文来源：http://www.gbppp.com/yc/402403/
推荐访问:关于plc的英文文献 关于plc的参考文献