Dynamic Performance Analysis And Intelligent Control For Thermal Conditions Of District Heating System

With the rapid city development in our country, the central heating system has become the main way. The energy source is relatively deficient in our country, and the energy efficiency is very low, only 32%, but 52% in the developed countries in the world. Obviously, there is a big difference with the developed countries. And the energy waste is serious in our country. To reasonably utilize the central heating source, reduce the production cost of heating source, keep a security of the city heating, a central heating system of Dafa heating company will be researched in this paper, the mathematical model of the heating system and dynamic process are studied, and a program of the operation adjustment is proposed. The main research contents is as follows:(1) To investigate the dynamic characteristics of the central heating system, based on the principle of heat transfer in the conservation of both mass and energy, the energy transmission and heat exchange relations of the heat source, the pipeline, and the heat consumer are analyzed. The mathematical models of each part are proposed.(2) Based on the mathematical model of the central heating system, the software package of the heating system dynamic characteristics is programmed using the Matlab /Simulink software, the operation characteristics of the heating system is analyzed.(3) With the variation of the outdoor temperature condition, the indoor temperature variation and the temperature of both the supply water and the return water of the primary network are simulated, which is regarded as a foundation for the regulation of the entire heating system.(4) The relation of between the boiler outlet temperature and outdoor temperature is further adjusted using expert control method, to achieve the intelligent control of the boiler outlet temperature laid the foundation.(5) On the basis of the boiler outlet temperature closed loop control, a fuzzy PID control scheme of both the heat user-primary network and the heat user-secondary network is further proposed with the intelligent control strategy. Meanwile, the simulation results show that the proposed method is better than the traditional PID control method. And the feasible guiding suggestion is provided for the Dafa company operation and production.