【正文】 采用進(jìn)口溫度控制儀表。目前，我國在這方面總體技術(shù)水平處于 20 世紀(jì) 80年代中后期水平，成熟產(chǎn)品主要以“點(diǎn)位”控制及常規(guī)的 PID 控制器為主，它只能適應(yīng)一般溫度系統(tǒng)控制，難于控制滯后、復(fù)雜、時(shí)變溫度系統(tǒng)控制。有的還具有自學(xué)習(xí)功能，它能夠根據(jù)歷史經(jīng)驗(yàn)及控制對(duì)象的變化情況，自動(dòng)調(diào)整相關(guān)控制參數(shù)，以保證控制效果的最優(yōu)化。（3）能夠適應(yīng)于受控系統(tǒng)過程復(fù)雜、參數(shù)時(shí)變的溫度控制系統(tǒng)的控制。采用單片機(jī)進(jìn)行溫度控制不僅具有控制方便、簡單和靈活性大等優(yōu)點(diǎn)，而且可以大幅度提高被控溫度的技術(shù)指標(biāo)。從工業(yè)爐溫、環(huán)境氣溫到人體溫度；從空間、海洋到家用電器，各個(gè)技術(shù)領(lǐng)域都離不開測溫和控溫。DS18B20。PID控制是由P, I, D三個(gè)環(huán)節(jié)的不同組合而成。一個(gè)控制系統(tǒng)包括控制器、傳感器、變送器、執(zhí)行機(jī)構(gòu)、輸入輸出接口。第三，系統(tǒng)軟件設(shè)計(jì)。本系統(tǒng)選擇的溫度傳感器就是DS18B20，系統(tǒng)開始工作時(shí)，DS18B20采集溫度信號(hào)并將信號(hào)送到單片機(jī)中，再將對(duì)應(yīng)的溫度送顯示并保存數(shù)據(jù)信息，同時(shí)單片機(jī)會(huì)根據(jù)初始化所設(shè)置的溫度進(jìn)行比較，將其差值送PID控制器，處理后輸出一定數(shù)值的控制量，根據(jù)控制量，控制晶閘管主回路的導(dǎo)通時(shí)間來調(diào)節(jié)輸入功率，從而控制電阻絲的發(fā)熱量，達(dá)到控制溫度的目的。目前常用的測溫傳感器分模擬和數(shù)字兩種方式：模擬方式如熱敏元件或熱電阻等；數(shù)字方式多采用智能芯片DS18B20。設(shè)計(jì)了硬件原理圖，并詳細(xì)論述了各個(gè)硬件組成部分的工作原理，以及各部分所使用的元器件?；贏VR單片機(jī)的爐溫監(jiān)測監(jiān)控系統(tǒng)設(shè)計(jì)總說明：溫度是工業(yè)對(duì)象中主要的被控參數(shù)之一，象冶金、機(jī)械、食品、化工各類工業(yè)中，廣泛使用的各種加熱爐、熱處理爐、反應(yīng)爐等，對(duì)工件的處理溫度要求嚴(yán)格控制。選擇DS18B20作為溫度傳感器，實(shí)時(shí)監(jiān)測低溫電阻爐溫度；基于交流觸發(fā)器和晶閘管觸發(fā)電路的混合控制，達(dá)到快速準(zhǔn)確調(diào)節(jié)溫度。首先是溫度傳感器的選擇。新代數(shù)字溫度傳感器DS18B20其優(yōu)點(diǎn)是：電壓適用范圍寬；單線接口數(shù)據(jù)傳輸方式；支持組網(wǎng)實(shí)現(xiàn)多點(diǎn)測溫；測溫范圍寬、精度高、體積小、外圍電路簡單等。根據(jù)單片機(jī)的I/O口設(shè)計(jì)硬件電路，合理分配I/O接口，電路設(shè)計(jì)簡潔、直觀，成本低廉，溫度測量準(zhǔn)確。第四，PID控制器的設(shè)計(jì)。PID控制器問世至今已有近70年歷史，它以其結(jié)構(gòu)簡單、穩(wěn)定性好、工作可靠、調(diào)整方便而成為工業(yè)控制的主要技術(shù)之一。關(guān)鍵詞：AVR單片機(jī)；DS18B20；PID控制；溫度檢測與控63 / 72The Furnace Temperature Monitoring System of AVR SCMGeneral introduction:Temperature is one of the main controlled parameters in industrial objects. All kinds of heating furnace, heat treatment furnace and radiators are widely used in the industry likes metallurgy, machinery, food and chemical industry, etc. It’s strictly controlled in the requirements of processing temperature. As the development of electronic technology and puter technology, puter measurement as well as the control technology obtains a rapid development and widespread application. Morever, the means of temperature control gets more and more superior. SCM gets a wide range of applications for the advantages of strong handling ability, fast running speed, low power consumption. Apart from this, the simple and convenient controlling, range measuring and high accuracy in temperature measurement and control makes it more and more popular.Using AVR SCM as the core, the article designs a furnace temperature monitoring system. It chooses DS18B20 as the temperature sensor to monitor the low temperature resistance furnace temperature. Based on the mix control of munication trigger and grain brake canal trigger circuit, it achieves the purpose of fast and accurate temperature adjustment. The article designs a hardware principle diagram to illustrate the working principle of all parts of the hardware and each branch of the ponents. Applying into the intelligent electric heating temperature control system, it meets the requirements of the temperature control stability, reduces the amounts of operators and human error, improves the product quality of heat treatment, eic.The overall design of AVR SCM Furnace temperature monitoring system includes the following three parts: the hardware circuit design of the temperature monitoring system, the design of the system software as well as the design of PID controller.First,the choice of temperature sensor. In nowadays, the mon temperature sensor has two ways, one is analog and the other is digital. For example, the emperature sensing elements and heat resistance belong to the analog way, and the digital one is mainly using intelligent chip DS18B20. Compared to the analog way, digital way has much more advantages, likes the Wide application scope of voltage, One interface data transmission, Multipoint, wide rage, high precision, small volume and simple peripheral circuit temperature measurement, etc. The temperature sensor chosen by the system is DS18B20. After the operating of the system, DSI8B20 collectes the temperature signal and sends it to the chip, after that, it displays the corresponding temperature and stores the data. At the same time, SCM will pare the real temperature with the initial set one and send the difference to the PID controller to get a output of a certain amount of control volume. And according to the control volume, it controls the thyristor circuit conduction time to adjust the input power and controls the calorific value of the resistance wire, aims to control the temperature.Second, the design of peripheral hardware circuit. Peripheral hardware circuit includes Temperature detection, Thyristor trigger circuit, Keyboard and LCD display circuit, Crystals circuit, Reset circuit, Alarm circuit, etc. The type of AVR SCM we choose is ATmega8. ATmega8 is aneightSCM based on AVR RISC structure, produced by a low power consumption CMOS. According to the I/O mouth SCM, we design the hardware circuit and distribute I/O interface resonably. The design is simple, intuitive, low cost and accuracy temperature measurement.Third, the design of System software. The designs of system software meets the requirements of system function. The software can be divided into two categories based on the system function. One is Implement software which can perform a variety of practical function, such as temperature measurement, calculation, display, output control, etc. The other one is Monitoring software which is dedicated to coordinate the various executive module and the operator, playing a role as a coordinater.Four, the design of PID controller. A control system includes the controller, sensors, transmitter, actuators and input/output output of the controller goes through the output interface and actuators and added to the controlled system. The quantity accused of the control system goes by the sensor, transmitter and sent to the controller through the input the engineering practice, the most widely used regulator control laws are Scale, Integral and Differential control, PID control for short. With the history of nearly seventy years, PID controller bees one of the main technologs in industrial control for the simple structure, good stability, convenient adjustment and reliable working. PID control is a bination of P, I, D.The basic principle of PID control is rather simple and its parameters of the physical meaning is rather clea