Research On The Application Of Phase Change Heat Storage Device In Centralized Heat-Supply System

China is a country with a large population.With the growth of the national economy and the improvement of people's living standards,their consumption of energy is increasing.Nowadays,China's total energy consumption has ranked first in the world.Among the energy consumption,the energy consumption of centralized heat-supply account for a large part of the north.However,in the north,there are still many largescale wind farms,and the large-scale “discarding the wind” situation has also received increasing attention from the state.Phase change thermal storag technology is a demandside management method to alleviate the increasing demand for heating while reducing the "abrogated wind" situation in a large area.The phase change heat storage technology shifts the peak heating load of the heat supply unit to increase the peak capacity of the cogeneration power plant,and at the same time,appropriately reduces the heat output of the cogeneration power plant,thus providing space for wind power consumption.This paper focuses on the application of phase change thermal storage device in a centralized heat-supply system.This paper first discussed the principle and classification of heat storage technology and phase change thermal storag technology.The layout,installation position and connection form of the phase change thermal storage device in the heat-supply network are discussed.By comparing and analyzing various characteristics of phase change heat storage and sensible heat storage,the optimal conditions and form of use of the phase change thermal storag technology device are sought.The analysis results show that the mode of heat storage of the phase change thermal storage device should adopt the distributed heat storage;the installation location should be located on the secondary circuit;the connection mode to the heat-supply network should be connected in parallel.Based on the use of phase change thermal storage devices,this paper establishes a technical and economic model for the total annual cost of heating systems with phase change heat storage at the planning level of the system.The model includes the system thermal model and the system economic model,and the particle swarm algorithm is used as the solution to the optimal solution of the model.Then taking Harbin as an example,the application of phase change thermal storage devices under the conditions of heatsupply in the city was analyzed.At the level of daily operation and scheduling of the system,a dynamic user system dynamic model and a daily operation optimization model were established.The former is based on the lumped parameter method,including the dynamic model of the envelope structure,the heat conduction model of the heating system and the dynamic heat balance model of the air in the building;the latter includes two supply models of uniform supply and non-uniform supply.Finally,taking a small commercial building as an example,the temperature and energy supply in the building under different supply models are analyzed to find the optimal daily operation strategy.