Dynamic Simulation and Thermodynamic Analysis of Energy Storage in Heat Supply Network
In order to improve the operational flexibility of cogeneration units,the dynamic model of 350 MW cogeneration unit and heat supply network system is established.The dynamic charac-teristics of heat supply network and heat user,the maximum heat storage capacity of heat supply network under different ambient temperature and heat user temperature boundary conditions,and the influence of heat storage and heat release capacity of heat supply network on the unit peak load capacity are studied.Results illustrate that the temperature of supply and return water and hot users are linearly related to the extraction flow rate.The maximum heat storage capacity decreases with the decrease of ambient temperature.When the ambient temperature decreased from 0℃ to-20℃,the maximum heat storage capacity decreased by 47.4%.When the ambient temperature de-creases from 0℃ to-20℃,the adjustment amount on the unit's peak regulation capacity increases from 6.9 MW to 9.6 MW.The thermal efficiency of the heat supply network is slightly increased with the increase of ambient temperature and extraction flow rate.But the exergy efficiency is low,it obviously increased with the increase of environmental temperature and extraction flow rate.
cogenerationheat storage of heat supply networkdynamic characteristics