【作者】 陈伟；

【导师】 毛志忠；

【作者基本信息】 东北大学 ， 控制工程（专业学位）， 2017， 硕士

【摘要】 电弧炉炼钢已有近百年的历史,近几十年来发展尤为迅速,在现代炼钢企业,电弧炉有着重要的地位。对于电弧炉来说,它在工作过程中,由于电弧弧长波动较大,导致电弧电流变化剧烈,从而导致对电网能量的冲击较大,影响严重,而对此解决的主要措施就是可以有一个精确实用的数学模型来描述电弧,从而方便对整个电极系统进行建模与控制研究。本文介绍了基于能量守恒定律,利用电弧弧长、电弧电流和电弧电导表示的新的电弧时变模型,该模型可以描述电弧外部特性与内部电热性质,是描述电弧比较精确的数学模型。对于该模型,本文主要讨论了模型参数的影响,并利用粒子群优化算法实现对模型参数的辨识。基于所建立的电弧模型,本文搭建了电弧炉电极调节系统,除了电弧模型,本文依据实际电弧炉工作环境,讨论了电弧炉的供电系统模型与传动机构液压系统模型。电极系统模型搭建完成后,可以实现针对电弧的特点来设计控制器解决电弧炉工作时可能出现的问题。对于电极控制策略的选择,本文讨论了恒电流控制策略、恒功率控制策略和恒阻抗控制策略,发现恒阻抗控制是更适合电极调节系统的控制策略。然后基于恒阻抗控制策略,本文利用PID控制器实现对于电极调节系统的控制仿真,从而证明了本文介绍的模型在对电弧炉的控制研究中是可行的。为了将所设计电极系统应用在实际的系统中,本文将所建立的电弧炉电极调节模型应用在仿真平台上,利用西门子的WinCC与STEP7软件在仿真平台上搭建了整个电极调节系统模型,并利用OPC技术实现Matlab与WinCC的数据互连来完成整个模型搭建,最后通过实验来探讨电弧的特性。仿真平台的功能实现可以更好的研究电弧炉其他的特性与控制方法。更多还原

【Abstract】 It has been nearly a century about steelmaking.Especially in recent decades its development is rapid.In the modern steel enterprise,electric arc furnace has a very important position.As for electric arc furnace,due to arc length is volatile in the working process which can cause dramatic arc current and leads to serious impact to the grid energy larger influences.And the main measure to solve the problem is to build an accurate and practical mathematical model to describe the arc which is convenient to control the whole electrode system so it can reduce the energy of the impact of power grids.In this thesis,we introduced a new arc model which is described by arc length,arc current and arc conductance based on the law of conservation of energy.The new arc model can describe the external features and internal electric properties of electric arc.As for this arc model,this thesis mainly studies the influence of model parameters,the identification method of the parameters and these can prove the correctness of the proposed model on describing the electric arc.In this thesis,we build the arc furnace electrode adjustment system based on the arc model.In addition to the arc model,based on the actual electric arc furnace working environment,we discuss the model of electric arc furnace power supply system and transmission mechanism hydraulic system model.By then the electric arc furnace electrode adjustment system model is completed.Since the model is completed,we can design controller to solve the problem of electric arc furnace.As for the choice of electrode control strategy,in this thesis we discuss the constant current control,constant power control and constant impedance control.And we find that the constant impedance control strategy is much more suitable for the electrode regulating system to build controller.Then based on the constant impedance control strategy,we use PID controller to realize the electrode control system simulation which is proved in this thesis that the model can be applied in the study of the control of the arc.In order to apply design of electrode system in the actual system,we design a simulation platform for the electric arc furnace on which we can use the established model.We use WinCC and the STEP7 software of Siemens on simulation platform to build the entire electrode regulating system and by using OPC technology to achieve data of matlab and WinCC interconnected to complete the entire system.At last,through experiments we investigate the properties of arc.The realization of the function of the simulation platform can make it easier for us to study arc control system in the next step.更多还原