1000MW直流炉机组非线性动态模型及闭环验证

Nonlinear Dynamic Model of a 1000 MW Once-through Boiler Unit and Its Closed Loop Validation

为获得适用于大范围变工况的超超临界机组机理模型,采用机理分析法建立了协调控制系统(包括制粉系统、锅炉系统和汽轮机系统)模型,输入量为燃料量指令、总给水量和汽轮机调门开度,输出量为汽水分离器蒸汽焓值、主蒸汽压力和机组功率.在参数辨识方面,静态参数采用机组稳态运行数据结合非线性回归分析获得;动态参数采用免疫遗传算法,结合大范围变工况运行数据求取,最后对所建立的机理模型进行静、动态模型验证.结果表明:此协调控制系统模型具有正确、简单的机理模型结构和较高的精度,可用于控制算法测试和协调控制系统设计.

The method of mechanism analysis was adopted to establish a mathematical model for the coordinated control system of an ultra-supercritical boiler unit over a wide operating range,including the coal pulverizing system,the boiler system and the turbine system,with coal quantity command,total feed water flow and opening degree of turbine valve as the inputs,and with steam enthalpy in separator,main steam pressure and unit power as the outputs.In term of parameter identification,the steady parameters were obtained by non-linear regression analysis combined with steady data;while the dynamic parameters were estimated by immune genetic algorithm（IGA）combined with operation data over a wide operating range.The mechanism model was then validated under both steady and dynamic conditions.Results show that the model owns proper and simple structure,with high accuracy,which therefore may serve as a reference for the testing of control algorithms and the design of CCS.