Research On Simulation And Optimization Strategy Of Complex Distributed Energy System

A distributed energy system is an energy system that is small in scale and scattered at the energy end and can independently output electricity,heating and cooling energy.It has the advantage of renewable energy consumption and emission reduction.At present,there are still problems in the research and utilization of distributed energy,such as a single fixed operating strategy,low participation of renewable energy,a mismatch between supply and demand,which hinder the in-depth research and promotion of its development.To address the above issues,this paper investigates distributed energy systems in terms of equipment modelling integration,operational strategy optimization,multi-energy complementation,supply-demand synergy,etc.The main research content and innovation points of this paper are as follows.(1)Integration and simulation of complex energy systems in an industrial parkIn this paper,the variable working condition simulation models of the gas turbine,gas-fired internal combustion engine,steam turbine,waste heat boiler,single-effect lithium bromide refrigeration unit,electric refrigeration unit,gas boiler,etc.are established in Aspen Plus,and a general method of packaging each device into a user model is proposed,which improves the portability of each device model and the humanmachine interaction friendliness of the simulation process.Based on the load characteristics of the industrial park,different integration scenarios for the combined renewable energy and gas-steam combined system were simulated using the models of the built equipments.(2)Multi-energy complementation in supply sideIn this paper,a principle of complementarity among gas-steam combined cycle,solar energy and energy storage is proposed from the perspective of time around the energy demand of industrial parks,that is,according to the ratio of electricity and heat load and the time distribution characteristics of solar radiation intensity on the energy side,the operation strategy of gas-steam combined cycle system and energy storage system can be adjusted,which could effectively use solar energy and improve the comprehensive index of distributed energy system while meeting the demand of users.(3)Supply-demand coordinationIn this paper,a time-of-use heat price model based on the ratio of electricity and heat load and radiation intensity are proposed.When the time-of-use electricity price and heat price are used at the same time,they can effectively reduce the peak-to-valley ratio of heat and power load on the customer’s side.For the energy system without energy storage,the time-of-use hybrid price has a better-integrated performance than the existing peak-to-valley electricity model.A comparative analysis of energy systems with different supply-demand coordination models and with or without energy storage,shows that there is a complementary substitution between th load that is transferred by the user and the energy stored in the energy storage system when their types are the same.If their types are not identical,it would be more effective to achieve multiple energy complementarities and improve the integrated performance of the energy system.