锅炉再热器温控制系统设计毕业论文.doc

锅炉再热器温度控制系统设计 摘要 PID控制器由于具有结构简单、实现容易，鲁棒性较强的优点，因此被广泛应用于锅炉再热器温度控制中。目前，热汽温控制中，热蒸汽出口温度控制要求高、可控性差，工艺上对热汽温控制的质量有非常严格的要求在安全性和经济性运行中有着重要的作用。由于热器具有大、非线性、时变、多变量和有自平衡能力等特点，如何提高热汽温的控制，是重要研究课题。 实现安全、经济、可靠、优化和环保的要求，具有广阔的应用前景。Boiler Reheater Temperature Control System Design Abstract Because the PID controller has the advantages of simple structure, easy realization, good robustness advantages, it is widely used in Boiler Reheater Temperature control. At present, the boiler reheat steam temperature control in reheat steam outlet temperature, high control requirements, poor controllability, technology of reheat steam temperature control quality has very strict requirements. The reheat steam temperature is relatively stable in boiler safety and economic operation has an important role in. As a result of reheater has great inertia, nonlinear, time-varying, multivariate and self balance ability and so on, how to use PID to improve the reheat steam temperature control effect, is the important research subject. In this paper, a more comprehensive parameters of PID controller tuning method based on the analysis of the current situation through the derivation of nonlinear robust controller with two degrees of freedom PI/PID controller equivalent form, put forward two degrees of freedom PI/PID parameter tuning rule - expected dynamic method ( DDE ); and the adoption of a power plant boiler reheater specific analysis and research, through the MATLAB simulation and traditional PID compared to illustrate this method is feasible, has to improve the boiler to realize safety, economy, reliability, optimization and environmental protection requirements, has a broad application prospect. Key words: PID，Boiler reheater，Two degree of freedom PID，MATLAB， Control effect。 引言 锅炉再热汽温系统是一个典型的非线性、时变、多变量系统,它的状态参数与运行工况密切相关。汽温控制的好坏直接影响其热效率的高低。然而,生产过程中往往存在较多的干扰因素,蒸汽负荷、烟气流量及温度、炉内燃烧工况、送引风情况、二次风和三次风的调整、给水流量压力及温度、受热面积灰及制粉系统启停等均对再热汽温有较大的影响。因此,迫切需要设计出具有较好鲁棒性的控制系统,并能够较快投入自动。 ；1955年，Cohen，Coon等人提出了Coh