摘要
发电厂脱硫供浆过程pH值调节存在强非线性和大滞后的问题,其实际控制系统设计及DCS实现存在一定难度。鉴于Smith预估器在大惯性和纯滞后系统控制中的应用效果,提出采用变参数自适应Smith控制系统对脱硫pH值进行调节。首先,基于实际控制对象特性分析,利用先验知识和最小二乘辨识理论对控制系统进行建模;然后,在此基础上进行了串级控制、Smith预估器以及变参数自适应Smith预估器的对比仿真研究,控制精度和稳定性结果表明变参数自适应Smith预估器具有明显控制优势。最后,对实际机组DCS进行变参数自适应Smith控制策略设计,成功地解决了机组脱硫供浆过程pH值控制的大惯性和纯滞后问题。多台其它机组的实际改造应用效果证明:该方法具有一定的推广应用前景。
Due to the strongly nonlinear and hysteresis problem in the power plant desulfurization slurry process, the actual pH adjustment control system and its implementation in DCS are extremely difficult. Considering the application of the Smith predictor in the strongly nonlinear and pure time delay control system, the parameter-variable adaptive Smith control system is proposed to adjust the pH value. First, analyze the characteristics of the actual control object and build the control system model using the prior knowledge and the least-squares identification theory. Then, on this basis, the comparison simulation study of cascade control, Smith estimator and parameter-variable adaptive Smith predictor is carried out. The results about accuracy and stability demonstrate that the parameter-variable adaptive Smith predictor has obvious advantages. Finally, this valuable method is designed and added in the DCS, which successfully solved the strongly nonlinear and hysteresis problems of the pH control. The practical application of multiple units proved this method has some prospects for promotion and application.
出处
《电站系统工程》
2019年第3期63-65,共3页
Power System Engineering
基金
国家重点研发计划项目(2017YFB0902101)资助
关键词
变参数自适应
SMITH预估器
脱硫pH值控制
惯性滞后
parameter-variable adaptive
Smith predictor
pH control in desulfurization
large inertia and pure lag
