Analysis And Optimization Design Of Boiler Side Modulating Control System For 600MW Unit

With the development of economy, power enterprises in China have began to face the issue of separation betweenpower plants and grid system, and there is anincreasing market competition on price bidding. Meanwhile, for power enterprises, they shouldon the one handface a further increase of production costs because of rising coal prices caused by energy shortages;on the other hand, these enterprises have to confront national restrictions onXNO emission. Therefore, all power enterprises urgently need to tap the potential and improve operational efficiency of generation units, so as to reduce production costs and make enterprises more competitive. Combustion optimization the boiler, which can effectively improve the operating efficiency of the unit, lower the cost of power generation, and reduceXNO emission, has receiveda lot of attention from the power plants.This paper relies on the project of #4 unit combustion optimization of a certain power plant in Guizhou, DaTang Corporation.In order to ensure the smooth progress of this project, we need to optimize the modulating control system(MCS) of one side of the boiler to improve the quality of MCS and meet the requirements of combustion optimization. Firstly, theoriginal control scheme and the field operation curve of the boiler side modulating control system(includs feed water control system; superheated temperature control system; secondary air damper control system; air flow and oxygen regulation system; cold air port and hot air port control system of coal pulverizer) are analyzed, and problems existing in the system are summarized. Secondly, the corresponding optimization scheme is put forward according to those problems and the control logic in the field is modified based on that scheme. Finally, do the site debugging onthe boiler side modulating control system, and debugs repeatedly to modified logic parameters until good control quality is obtained.In addition, we also analyze the original control logic of coordinated control system,and summarizethe problems existing in the system, in the meantime present the optimization scheme accordingly.