电阻炉的温度控制系统设计课程设计

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电阻炉的温度控制系统设计

摘要

电阻炉在冶金工业中的运用相当广泛,其温度参数在生产过程中的自动控制系统也随着微机单片机可控硅技术在工业控制领域的推广、应用,正朝着高精度、高稳定性、高智能化的方向发展。电阻加热炉是典型的工业过程控制对象。其温度控制具有升温单向性、大惯性、大滞后、时变性等特点，且其升温、保温是依靠电阻丝加热，降温则是依靠环境自然冷却。

温度是工业对象中主要的被控参数之一。尤其是在冶金、化工、机械各类工业中，广泛使用各种加热炉、热处理炉、反应炉等。由于炉子的种类不同，所采用的加热方法及燃料也不相同，如煤气、天然气等。但就控制系统本身的动态特性而言，均属于一阶纯滞后环节，在控制算法上基本相同，可采用PID控制或其他纯滞后补偿算法。但对于电阻加热炉来说，当其温度一旦超调就无法用控制手段使其降温，因而很难用数学方法建立精确模型和确定参数。而传统PID控制是一种建立在经典控制理论基础上的控制策略，其设计依赖于被控对象的数学模型，因此对于加热炉这类控制对象采用传统PID的控制方案很难达到理想的控制效果。

为了保证生产过程正常安全地进行，提高产品的质量和数量，以及减轻工人的劳动强度，节约能源，对加热用的各种电炉要求在一定条件下保持恒温，不能随电源电压波动或炉内物体而变化，或者有的电炉的炉温根据工艺要求按照某个指定的升温或保温规律而变化，等等。

因此，在工农业生产或科学实验中常常对温度不仅要不断地测量，而且要进行控制。在电阻炉温度控制系统的设计中，应尽量考虑到如何有效地避免各种干扰因素而采用一个较好的控制方案，选择合适芯片及控制算法是非常有必要的本设计要用单片机设计一个电阻炉温度控制系统。

关键词：恒温；热处理；控温系统

Design for T emperature Control System of Resistance Furnace

Abstract

The resistance furnace in metallurgical industry is widely application, its temperature parameters 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 preservation and heat resistance wire depend on environment, cooling is natural cooling.

T emperature is the main objects of accused of parameters. Especially in metallurgy, chemical, machinery, widely used in various industries of heating furnace, heat treatment furnace, reactors. Because 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 itself, 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 use control means that the cooling, so it is difficult to use mathematical method to establish precise model and parameters. While the traditional PID control is an established in classical control theory, the control strategy based 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, select the appropriate chip and control algorithm is necessary to the design with a single-chip microcomputer temperature control system of resistance furnace.

Keywords: temperature；Heat treatment；Temperature control system