電阻爐的溫度控制系統(tǒng)設(shè)計(jì) 摘要
電阻爐在冶金工業(yè)中的運(yùn)用相當(dāng)廣泛,其溫度參數(shù)在生產(chǎn)過程中的自動(dòng)控制系統(tǒng)也隨著微機(jī)單片機(jī)可控硅技術(shù)在工業(yè)控制領(lǐng)域的推廣、應(yīng)用,正朝著高精度、高穩(wěn)定性、高智能化的方向發(fā)展。電阻加熱爐是典型的工業(yè)過程控制對(duì)象。其溫度控制具有升溫單向性、大慣性、大滯后、時(shí)變性等特點(diǎn)，且其升溫、保溫是依靠電阻絲加熱，降溫則是依靠環(huán)境自然冷卻。
溫度是工業(yè)對(duì)象中主要的被控參數(shù)之一。尤其是在冶金、化工、機(jī)械各類工業(yè)中，廣泛使用各種加熱爐、熱處理爐、反應(yīng)爐等。由于爐子的種類不同，所采用的加熱方法與燃料也不一樣，如煤氣、天然氣等。但就控制系統(tǒng)本身的動(dòng)態(tài)特性而言，均屬于一階純滯后環(huán)節(jié)，在控制算法上基本一樣，可采用PID控制或其他純滯后補(bǔ)償算法。但對(duì)于電阻加熱爐來說，當(dāng)其溫度一旦超調(diào)就無法用控制手段使其降溫，因而很難用數(shù)學(xué)方法建立精確模型和確定參數(shù)。而傳統(tǒng)PID控制是一種建立在經(jīng)典控制理論基礎(chǔ)上的控制策略，其設(shè)計(jì)依賴于被控對(duì)象的數(shù)學(xué)模型，因此對(duì)于加熱爐這類控制對(duì)象采用傳統(tǒng)PID的控制方案很難達(dá)到理想的控制效果。
為了保證生產(chǎn)過程正常安全地進(jìn)行，提高產(chǎn)品的質(zhì)量和數(shù)量，以與減輕工人的勞動(dòng)強(qiáng)度，節(jié)約能源，對(duì)加熱用的各種電爐要求在一定條件下保持恒溫，不能隨電源電壓波動(dòng)或爐物體而變化，或者有的電爐的爐溫根據(jù)工藝要求按照某個(gè)指定的升溫或保溫規(guī)律而變化，等等。
因此，在工農(nóng)業(yè)生產(chǎn)或科學(xué)實(shí)驗(yàn)中常常對(duì)溫度不僅要不斷地測(cè)量，而且要進(jìn)行控
制。在電阻爐溫度控制系統(tǒng)的設(shè)計(jì)中，應(yīng)盡量考慮到如何有效地避免各種干擾因素而采用一個(gè)較好的控制方案，選擇合適芯片與控制算法是非常有必要的本設(shè)計(jì)要用單片機(jī)設(shè)計(jì)一個(gè)電阻爐溫度控制系統(tǒng)。
關(guān)鍵詞：恒溫；熱處理；控溫系統(tǒng)
Design for Temperature Control System of Resistance Furnace
Abstract
The resistance furnace in metallurgical industry is widely application, its temperature para
meters in the production process of automatic control system with single-chip microcomputer control technology in the field of industrial silicon, the popularization and application in high precision, high stability, high intelligent direction. Resistance furnace is typical of industrial process control object. The temperature control with temperature mono-direction and large inertia, the lag and time-varying characteristics, such as temperature, heat prervation and heat resistance wire depend on environment, cooling is natural cooling.
Temperature is the main objects of accud of parameters. Especially in metallurgy, chemical, machinery, widely ud in various industries of heating furnace, heat treatment furnace, reactors. Becau of the different kinds of heating method is adopted, and the fuel is not identical also, such as coal gas, natural gas etc. But control system dynamic characteristics of itlf, all belong to a first-order lagging pure, in the same basic control algorithm, PID control or other pure lag compensation algorithm. But for resistance furnace, when the temperature once overshoot cannot u control means that the cooling, so it is difficult to u mathematical method to establish preci model and para
meters. While the traditional PID control is an established in classical control theory, the control strategy bad on its design depend on mathematical model of the controlled objects, so this kind of control for furnace adopts the traditional PID control object to achieve the ideal control scheme.
In order to guarantee the normal production process, improve product safely quantity and quality and to reduce the labor intensity, energy saving, with all kinds of electric heating requirements under certain conditions, not with remains constant voltage fluctuations or furnace changes, or some objects according to the technical requirement of electric furnace temperature or a designated in accordance with the law and heat changes, etc.
Therefore, in industrial and agricultural production and scientific experiments to constantly measuring temperature will not only, and to control System.In the resistance furnace temperature control system design, should try to consider how to effectively avoid distractions and USES a better control scheme, lect the appropriate chip and control algorithm is necessary to the design with a single-chip microcomputer temperature control system of resistance furnace.
