内模控制在火电厂主汽温系统中的应用

发布时间：2018-03-12 06:19

本文选题：主蒸汽温度　切入点：串级PID控制　出处：《华北电力大学》2014年硕士论文　论文类型：学位论文

【摘要】：在火力发电厂中，主蒸汽温度具有大滞后，大惯性，时变和非线性动态特性，在工况条件变化大时传统的串级PID控制难以获得满意的控制性能。内模控制结构简单，结构设计直观，调节参数少，易于调整，尤其是对控制系统鲁棒性及抗干扰性的改善和大时滞系统的控制，效果较为明显。本文对主蒸汽温度的特性进行了研究，分析了影响主汽温的三种主要扰动，分析了主汽温控制的重要性和难点，确定了主汽温的控制手段，明确了主汽温内模控制系统的设计原则，并结合内模控制和串级控制的优点，设计了内模-PID串级控制系统。为了快速消除内扰，，使控制过程的持续时间较短，有效地补偿对象的大时滞特性，内回路采用了比例控制，外回路采用了内模控制。以某600MW超临界直流锅炉高温过热器主汽温的动态特性为参数，使用SIMULINK软件进行仿真研究，并与常规串级PID控制系统作了比较。仿真结果表明，本文所设计的内模-PID串级控制系统的位置跟随性能、抗干扰性能和鲁棒性较为优秀，其综合性能优于常规串级PID控制系统。
[Abstract]:In the thermal power plant, the main steam temperature has the characteristics of large lag, large inertia, time-varying and nonlinear dynamic characteristics. The traditional cascade PID control is difficult to obtain satisfactory control performance when the operating conditions change greatly. The internal model control structure is simple. The structure design is intuitionistic, the adjustment parameter is few, the adjustment is easy, especially the improvement of the robustness and anti-interference of the control system and the control of the large time-delay system, the effect is obvious. The main steam temperature characteristic is studied in this paper. Three main disturbances affecting the main steam temperature are analyzed, the importance and difficulty of the main steam temperature control are analyzed, the control method of the main steam temperature is determined, and the design principle of the main steam temperature internal model control system is defined. Combined with the advantages of internal model control and cascade control, the internal model-PID cascade control system is designed. In order to eliminate the internal disturbance quickly, make the duration of the control process shorter and compensate the large time-delay characteristic of the object effectively, the internal loop adopts proportional control. The internal model control is adopted in the outer loop. The dynamic characteristics of the main steam temperature of a 600MW supercritical once-through boiler's high temperature superheater are taken as the parameters, and the simulation is carried out with SIMULINK software, and compared with the conventional cascade PID control system. The simulation results show that, The position following performance, anti-interference performance and robustness of the internal model-PID cascade control system designed in this paper are excellent, and its comprehensive performance is superior to that of the conventional cascade PID control system.
【学位授予单位】：华北电力大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TP273;TM621

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