火电厂主汽温系统扰动消除设计方法

火电厂主汽温系统具有大惯性、大延迟和时变等特性,采用常规PID串级控制方法解决主汽温系统的扰动消除问题,结果不甚满意。基于自适应逆控制理论,研究了主汽温系统扰动消除方法,并对实际600MW锅炉高温过热器的动态特性进行了仿真分析。针对主汽温系统导前区和惰性区的内、外2个回路,单独设计相应的扰动消除滤波器,导前区内回路的扰动被从内反馈回路滤波得到的扰动参考信号消除;惰性区输出端扰动从外反馈回路滤波得到扰动参考信号,在对象输入端实现扰动消除。仿真结果表明,该方案可较好地解决主汽温系统存在的内、外扰动问题,对主汽温系统的扰动消除具有较强的鲁棒性和自适应能力。

Disturbance canceling design for the main steam temperature system of thermal power plant

As the main steam temperature system in power plant are characterized by large inertia,long time lag and time-variation,satisfying result can not be obtained with conventional PID cascade control method to eliminate the disturbances for this system.Based on the theory of adaptive inverse control,the disturbance canceling method for the main steam temperature system was studied,and the dynamic characteristic of high temperature superheaters for certain supercritical 600 MW boiler was simulated in this paper.As for the leading and inertial section,the responding disturbance canceling filters were designed respectively,as a result the output disturbance of leading section is canceled by the reference signal from the filter in inner feedback loop,and then the disturbance of inertial section output is canceled on the input of plant by the reference signal from the outer feedback loop.The simulation result shows that this method can solve the disturbance problems and has strong robustness and self-adaptability for disturbance canceling of the main steam temperature system.