基于模糊决策的主汽温多模型内模控制

Multi-Model Internal Model Control of Main Steam Temperature Based on Fuzzy Decision

电厂主汽温系统具有大惯性、大迟延特性,在变工况条件下模型呈现非线性特点。传统的PID控制策略存在调节缓慢、难以适应工况变化等缺点,造成了现场主汽温控制自动投入率低、热效率不高。采用基于模糊决策的多模型内模控制策略,通过机组典型负荷工况下辨识得到的模型求取系统内模控制器,采用模糊决策得到各内模控制器输出的加权值。将上述方法运用于主汽温控制。通过仿真,与传统控制策略相比,系统各项性能指标均有提升,给现场主汽温控制提供了新思路。

The main steam temperature system of the power plant has large inertia and large delay characteristics,and the model exhibits nonlinear characteristics under variable working conditions.The traditional PID control strategy has the disadvantages of slow regulation and difficulty in adapting to changes in working conditions,resulting in the disadvantages of low automatic input rate and low thermal efficiency of the main steam temperature control on site.This paper adopts multi-model internal model control strategy based on fuzzy decision.The internal model controller of the system was obtained based on the model identified under typical load conditions of the unit,and the weighted value of each internal model controller was obtained through fuzzy decision.This method was applied to the main steam temperature control.Through simulation,compared with the traditional control strategy,the performance indicators of the system have been improved,which provides a new idea for the on-site main steam temperature control.