Characteristic Modeling And Operating Anaysis Of The Combined Cooling Heating And Power

The cogeneration system is an energy service system that is connected to a fuel supply pipeline such as a public power grid and natural gas to generate and deliver electricity,cold energy and heat energy to users in a certain area.The combined heat and power cogeneration system based on gas-steam combined cycle can be widely used because of its ability to use gas and steam combined cycle power generation.However,in the actual operation process of the cogeneration system,the cogeneration system is usually operated under poor operating conditions due to fluctuations in the load on the user side and the lack of operating strategy of the operating personnel.The energy saving potential of the electricity supply system is not fully exploited.Based on the equipment characteristics of the cogeneration system,this paper considers various indicators and analyzes the effects of different operation modes and different influencing factors on the system operation strategy under different load conditions.And determine its optimal operation strategy.The main research contents and innovations of this paper are as follows:(1)This paper selects the load of the office building group in the Tongzhou Canal Business District of Beijing as the energy-using side object.Its main energy consumption types include cooling load,heat load and electric load.The Dest building simulation software obtains the classification energy of the main energy-using units.Time distribution,and superposition to obtain the total energy curve.From the perspectives of the whole year,month and typical day,the load characteristics of the office buildings are analyzed,and the proportion of the hot and cold load,the peak value and the corresponding change trend are determined.(2)In this paper,for the gas-fired combined cycle system configuration in a given cogeneration system and the gas boiler and other equipment in the sub-supply system,combined with the design data and operational data,a combination of mechanism modeling and data driving is established.Cogeneration system and distribution system equipment characteristics model.In this paper,a characteristic modeling method based on the general characteristic curve of compressor is proposed.This method improves the applicability of the model by error function correction.(3)Aiming at the large capacity range of the gas-steam combined cycle cogeneration system and the complicated operation mode,this paper puts forward the energy saving rate under the premise of considering the parallel operation of the gas turbine and the steam turbine valve.(Primary Energy Saving,PES)Optimal operation mode and Operating Costing Saving(OCS)optimal operation mode.From the perspective of different time scales,this paper analyzes the controllable parameter changes of the cogeneration system under the traditional operation mode and the optimal operation mode,the balance of supply and demand and the change of indicators,and verifies the two operation modes proposed in this paper.Compared with the traditional operation mode,it has advantages in energy saving and economy.(4)In the actual operation process of the cogeneration system,the operation mode and indicators are often affected by many factors.This paper has carried out the cogeneration system from the perspectives of load fluctuation,natural gas price,net electricity price and electric cooling ratio.Sensitivity analysis.Through the analysis,the change trend of different optimization operation strategies and the change of indicators in different time periods of the co-supply system under different parameters are obtained,and the optimal operation strategy under different external conditions is proposed.The optimal electric cooling ratio of the co-supply system under PES optimal and OCS optimal operation is determined to be 0.5.The critical natural gas price and net electricity price under the OCS optimal operation mode are 4.4521 yuan/m3 and 0.4502 yuan/k Wh,respectively.Under the optimal operation mode,the critical natural gas price and the net electricity price are 4.2813 yuan/m3 and 0.4515 yuan/k Wh,respectively.