Characteristic Analysis Of Heat Pump Coupled Heat And Power Cogeneration Heating System

In the background of growing shortage of energy and low energy efficiency, this paper proposes a new heating mode, which is called heat pump coupled cogeneration heating system. This heating system not only can recover the waste heat of the circulating water in power plant, but also can improve the energy efficiency and heating capacity of the power plant. The heating system can effectively address the insufficient heating capacity of cogeneration units, the limited heating range, the low water temperature of heat pump, the variable load operation of heat pump and poor economy of heat pump and so on.The main content of this paper is the characteristic analysis of heat pump coupled cogeneration heating system, and the main research method is calculation method of variable conditions based on energy balance. Firstly, it introduces the basic operating principles and existing defects of several existing heating systems. Thereby the coupling heating system is proposed, and its working principle and structure are described in detail. It also explains the coupling heating system how to control to compliance with the design requirements. While for the heat pump coupled cogeneration heating system, the mathematical models of heating equipments and the entire coupling system under variant working conditions are established. The coupling heating system’s operating characteristics is analysed when the working conditions change, and thermal-electrical characteristic relationship of the entire coupling heating system is obtained. It can lay the theoretical foundation for the coupling heating system’s actual operation. This paper takes the mathematical models under variable conditions as research methods and compares the differences between coupling heating system and uncoupling heating system. The result indicates that the coupling heating system is superior to the uncoupling heating system in the thermal economy. Secondly, this paper also presents a techno-economic model. The coupled heating system and non-coupled heating system are carried on a comparative study analysis in this techno-economic model. The result shows coupled heating system can not only guarantee heat pump under constant load operation in the entire heating season, and its technical and economic is also higher than the uncoupled heating system. In addition, the FLUENT software is used to simulate the coupler, which is the core device of coupled heating system. Through the structural design and optimization, an ideal coupling model is obtained. Finally, the difference between the range of power load peaking of coupled heating system and the range of power load peaking of traditional cogeneration are analyzed. And the characteristics of power load peaking of coupled heating system is analyzed under different conditions. The results show the coupled heating system for improving the range of power load peaking also has certain advantages.