火电厂DCS控制系统优化研究与应用
发布时间：2018-10-20 07:30
【摘要】：随着科技的快速发展和环境保护意识、可持续发展战略思想的增强,未来发展要求我们在有限的能源中发挥最大的能量。大型燃煤火电厂是我国的重要的能源行业和支柱产业,能源消耗方面具有重要地位。工业常规控制方案采用PID线性控制算法的反馈控制回路,但PID控制是简单的一自由度控制器,在要求系统同时具有快速设定值响应能力和对干扰的抑制能力两方面的情况下控制并不理想。DCS(Distributed Control System)集散式分布控制系统,目前因为控制范围广泛集中监控管理等优点被我国大多数火电厂所应用,本文结合DCS系统对PID控制器进行组态改进使输出更优控制过程。首先对火电厂锅炉发电过程及现场机组工作流程做简单解说,明确了控制过程的目的及要求。将锅炉控制系统主要工艺流程分为四大部分做以说明:汽包水位控制,最佳燃空比控制,锅炉蒸汽压力恒定控制,炉膛负压恒定控制。其次考虑各部分控制系统间的相互影响,对实际控制对象建模并设计选择不同的控制回路:(1)控制燃料量和空气量的配比来提高燃烧效率,使控制过程中不出现缺氧或过氧燃烧造成能源浪费。(2)蒸汽压力控制采用内外串级控制系统,在易受到燃料量突变时可使蒸汽压力快速稳定恢复恒定值。(3)炉膛负压恒定系统通过锅炉内引风机和送风机的共同协调控制,系统引风机为主控制回路送风机作为误差干扰信号,设计二自由度PID控制器削减干扰信号影响从而提高控制精度。通过使用Simulink仿真对以上三种不同控制系统中2-DOF-PID控制器参数整定,对比传统PID控制输出图可以得知二自由度PID控制器可以同时满足输出设定值特性和抗干扰特性两个方面。最后对实际DCS火电控制组态二自由度控制器提高系统稳定性和抗干扰性,采集数据绘制的趋势表明二自由度PID控制器对目前工业控制过程有改进。本文重点难点在不同控制系统结合实践经验设计二自由度PID控制器并总结参数整定过程及方法,使系统在快速稳定的控制基础上更具有强的抗干扰性。结构简单实用性强,成本低控制精度高,增强了系统的鲁棒性能,在DCS工业控制领域具有良好的发展前进。
[Abstract]:With the rapid development of science and technology and the awareness of environmental protection and the enhancement of the strategic thought of sustainable development, the future development requires us to exert the maximum energy in the limited energy resources. Large-scale coal-fired thermal power plant is an important energy industry and pillar industry in China, and energy consumption plays an important role. The conventional industrial control scheme adopts the feedback control loop of PID linear control algorithm, but the PID control is a simple one degree of freedom controller. Under the condition that the system is required to have both the ability of fast response and the ability to suppress interference, it is not ideal to control the distributed. DCS (Distributed Control System) distributed control system. At present, most thermal power plants in our country have applied the advantages of extensive centralized monitoring and management in the control range. This paper combines the DCS system to improve the configuration of the PID controller to make the output more optimal control process. Firstly, the paper gives a brief explanation of the power generation process and the work flow of the field unit in the thermal power plant, and clarifies the purpose and requirements of the control process. The main process flow of boiler control system is divided into four parts: drum water level control, optimal ratio of fuel to air control, boiler steam pressure constant control, furnace negative pressure constant control. Secondly, considering the mutual influence of each part of the control system, the actual control object is modeled and different control loops are designed and selected: (1) to improve combustion efficiency by controlling the ratio of fuel quantity and air quantity; During the control process, there is no oxygen or superoxide combustion resulting in energy waste. (2) the internal and external cascade control system is used for steam pressure control, and the internal and external cascade control system is used to control the steam pressure. The steam pressure can be quickly and stably restored to a constant value when the fuel quantity changes easily. (3) the furnace negative pressure constant system is controlled by the co-coordinated control of the induced fan and the supply fan in the boiler, and the main control loop fan of the system is used as the error disturbance signal. A two-degree of freedom PID controller is designed to reduce the influence of interference signal and improve the control accuracy. By using Simulink simulation to adjust the parameters of the 2-DOF-PID controller in the three different control systems mentioned above, compared with the traditional PID control output diagram, it can be known that the two-degree-of-freedom PID controller can satisfy both the output set value characteristic and the anti-interference characteristic simultaneously. Finally, the system stability and anti-interference are improved for the actual DCS thermal power control configuration two-degree-of-freedom controller. The trend of data acquisition shows that the two-degree-of-freedom PID controller has improved the current industrial control process. In this paper, a two-degree-of-freedom PID controller is designed based on different control systems and practical experience, and the process and method of parameter setting are summarized, so that the system has stronger anti-interference on the basis of fast and stable control. The structure is simple and practical, the cost is low, the control precision is high, the robust performance of the system is enhanced, and the system has a good development in the field of DCS industrial control.
【学位授予单位】：西安电子科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TP273;TM621
本文编号：2282471
[Abstract]:With the rapid development of science and technology and the awareness of environmental protection and the enhancement of the strategic thought of sustainable development, the future development requires us to exert the maximum energy in the limited energy resources. Large-scale coal-fired thermal power plant is an important energy industry and pillar industry in China, and energy consumption plays an important role. The conventional industrial control scheme adopts the feedback control loop of PID linear control algorithm, but the PID control is a simple one degree of freedom controller. Under the condition that the system is required to have both the ability of fast response and the ability to suppress interference, it is not ideal to control the distributed. DCS (Distributed Control System) distributed control system. At present, most thermal power plants in our country have applied the advantages of extensive centralized monitoring and management in the control range. This paper combines the DCS system to improve the configuration of the PID controller to make the output more optimal control process. Firstly, the paper gives a brief explanation of the power generation process and the work flow of the field unit in the thermal power plant, and clarifies the purpose and requirements of the control process. The main process flow of boiler control system is divided into four parts: drum water level control, optimal ratio of fuel to air control, boiler steam pressure constant control, furnace negative pressure constant control. Secondly, considering the mutual influence of each part of the control system, the actual control object is modeled and different control loops are designed and selected: (1) to improve combustion efficiency by controlling the ratio of fuel quantity and air quantity; During the control process, there is no oxygen or superoxide combustion resulting in energy waste. (2) the internal and external cascade control system is used for steam pressure control, and the internal and external cascade control system is used to control the steam pressure. The steam pressure can be quickly and stably restored to a constant value when the fuel quantity changes easily. (3) the furnace negative pressure constant system is controlled by the co-coordinated control of the induced fan and the supply fan in the boiler, and the main control loop fan of the system is used as the error disturbance signal. A two-degree of freedom PID controller is designed to reduce the influence of interference signal and improve the control accuracy. By using Simulink simulation to adjust the parameters of the 2-DOF-PID controller in the three different control systems mentioned above, compared with the traditional PID control output diagram, it can be known that the two-degree-of-freedom PID controller can satisfy both the output set value characteristic and the anti-interference characteristic simultaneously. Finally, the system stability and anti-interference are improved for the actual DCS thermal power control configuration two-degree-of-freedom controller. The trend of data acquisition shows that the two-degree-of-freedom PID controller has improved the current industrial control process. In this paper, a two-degree-of-freedom PID controller is designed based on different control systems and practical experience, and the process and method of parameter setting are summarized, so that the system has stronger anti-interference on the basis of fast and stable control. The structure is simple and practical, the cost is low, the control precision is high, the robust performance of the system is enhanced, and the system has a good development in the field of DCS industrial control.
【学位授予单位】：西安电子科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TP273;TM621
【参考文献】
相关期刊论文 前2条
1 陈永会;谭功全;谭飞;傅成华;;一阶时滞过程二自由度PID控制器优化法[J];昆明理工大学学报(自然科学版);2011年04期
2 杨延西;刘丁;;基于模糊遗传算法的二自由度PID控制器优化设计[J];仪器仪表学报;2006年08期
，本文编号：2282471
本文链接：https://www.wllwen.com/kejilunwen/dianlilw/2282471.html
