超临界600MW机组直流锅炉动态特性研究

STUDY ON DYNAMIC BEHAVIOR OF ONCE-THROUGH BOILER EUIPPED FOR SUPERCRITICAL 600 MW UNIT

建立了沁北电厂超临界600MW机组直流锅炉的动态特性数学模型,包括单相受热管集总参数模型、单相受热管压力-流量通道集总参数模型、两相受热管段集总参数模型、烟气侧放热模型、喷水减温器模型等,以及汽轮机模型。通过数字仿真对该锅炉的动态特性进行了研究,对如给水温度阶跃增加5%、给水流量阶跃增加5%、燃料量阶跃增加5%、过热器减温喷水量阶跃变化、再热器喷水量阶跃变化等各种扰动发生后锅炉动态响应的稳定性、响应幅度以及扰动对锅炉的影响进行了分析。

The mathematic model of dynamic behavior for once-through boiler of supercritical 600 MW unti in Qinbei Power Plant has been established,including the lumped parameter model of single-phase heating pipes,the lumped parameter model of pressure-flow rate passage for single-phase heating pipe,the lumped parameter model of two-phase heating pipe sections,the exothermic model of flue as side,the model of spray desuperheater,and the model of steam turbine etc..Through numerical emulation,the dynamic behavior of said boiler has been studied,the stability of dynamic response,the amplitude of said response after any disturbance,such as step increase of 5% in feed-water temperature,in feed-water flow rate,in fuel coal amount,in spray water flow for desuperheating in superheater and reheater etc.,as well as the influence of said disturbances upon dynamic behavior of the boiler,have been analysed,providing certain guiding effect for manufacture,operation,and control of supercritical once-through boiler.