Simulation Of Cogeneration Units And Self-tuning Strategy Based On Operation Characteristics

With the development of national economy,the demand of heating for civil usage and industrial production is increasing rapidly.As a result,the heat and power cogeneration technology appeared,which could make use of exhaust steam or extraction steam for heating after driving steam turbine to generate electricity.Nevertheless,enslaved to the complex coupling relationship between thermal and electric load,the self-tuning strategy is not perfect enough in current industry.Weak algorithm will cause frequent action of hydraulic servo-motor,and further abrasion or leaking.So in some thermal power plants,operators would rather removing auto-control,and adjust thermal or electric load manually in depend of experience instead.Traditional self-tuning algorithms are lack of in-depth reflection on the thermal characteristics of the specific unit and the flow characteristics of specific regulating mechanism,which is the reason of weak adjusting ability.In this paper,a new kind of self-tuning strategy based on operational characteristics is put forward.In detail,firstly the flow rate of main steam regulating mechanism and cogeneration regulating mechanism could be calculated according to the operating condition diagram,then valve opening degree can be calculated according to flow curve.Meanwhile,the negative feedback regulation on electric power and the pressure of the heating steam outlet is supplemented to meet the demand of the thermal and electric load.The CC100-8.83/4.12/1.47 cogeneration unit made of Shanghai Turbine Works Company Limited is taken as the research object.According to its heat balance diagrams and other necessary design data,the dynamic numerical simulator can be established based on Lab VIEW software platform.Furthermore,the new self-tuning strategy described in this paper is applied on the simulator.After single stage extraction and double stage extraction off-design experiments,this strategy is proved to be able to control thermal and electric load at the same time nicely.