Study On Control Model Of District Heating System Based On Load Forecasting

With the continuous improvement of people's living standards,the demand for housing has also increased accordingly.Although it has contributed to the development of the urban heating industry,it has also directly increased energy consumption,especially the existence of excessive heating,which has led to a large amount of energy waste.With the development of automatic control technology in recent years,it is particularly necessary to establish a reliable simulation model of the entire district heating system to study its dynamic characteristics in order to conduct effective regulation and more accurately match the heat supply and the building's heat demand.Taking the central regulation of district heating system as the research object,this paper starts from the thermal balance of the system and divides the whole heating system into five parts: boiler,heating pipe network,building envelope,radiator and indoor temperature.Firstly,the dynamic mathematical model corresponding to each part is established by using the specific heat particle method,and then the simulation modules of several parts are built by MATLAB/Simulink software.The physical model is introduced to connect and set up the modules according to the specific conditions of the project.Then,based on the entire heating system simulation model,three different adjustment modules are added: the method of constant flow and constant water supply temperature regulation,the regulation of water supply temperature and flow according to outdoor temperature,and the regulation module based on load prediction.Finally the simulation model is used to study the fluctuation of indoor temperature and the energy consumption of boiler and water pump in three periods of winter design day,January and the whole heating season.By running the simulation model of the district heating system that introduces three different regulation schemes,it is found that the heating operation regulation method based on load prediction can reduce the indoor temperature fluctuation to a range of 20±1°C.Compared with the previous two regulation modes,the energy saving rate can reach 29.53% and 14.54% in the whole heating season respectively.So the control effect is relatively ideal.