| With the rapid development of China’s high-energy-consuming industries and the growing demand for high-quality energy from the people,as an important branch of the Energy Internet,the integrated energy system is a key way to fundamentally solve the problem of low comprehensive utilization of fossil energy and the elimination of renewable energy.The integrated energy system provides distributed and integrated cold/heat/electricity supply services based on energy conversion technology,renewable energy utilization technology,distributed energy technology,advanced information technology and the ideas of multi-energy complementation and energy cascade utilization.This article takes the integrated energy system as the research object,studies the characteristics of the core equipment and the renewable energy utilization process of the system,and establish two integrated energy system solutions which based on CCHP,and the CO2 working fluid cycle;Furthermore,a two-level optimization method for capacity allocation and operation strategy of conventional integrated energy systems is proposed to effectively improve the system’s economics and coordination capabilities.The two integrated energy systems and the sub-supply systems are compared in terms of economics and environmental protection.First,an integrated energy system based on combined cooling,heating,and power generation is proposed,which takes full account of the characteristics of renewable energy access,analyzes the energy coupling relationship and operating characteristics of various types of equipment,and integrates the modeling of the system;at the same time,the operating characteristics curves of the gas turbine are used for data fitting,and variable operating condition correction factors are set to improve the accuracy of the gas turbine energy conversion model;fully consider the access of multiple types of energy storage equipment,and increase the flexibility of the system under uncertain renewable energy input and electricity price changes.Secondly,determine the optimization of the capacity allocation and operation strategy as the system optimization direction,use the two-level optimization idea to design the optimization method;analyze the operating characteristics of the equipment,and build the optimization model constraints and optimization goals with investment and operation and maintenance,renewable energy consumption,resource consumption and other indicators;further use the combination of genetic algorithm and mixed integer linear programming solver to verify the economical efficiency and environmental protection of the integrated energy system considering energy storage and full consumption of renewable energy.Finally,the core of the integrated energy system is extended to the direction of using CO2 as a circulating working fluid.The building load simulation software and engineering equation solver are used to simulate the calculation of the integrated energy system based on CO2 cycle.The feasibility and particularity of the system are analyzed in terms of energy consumption performance and environmental impact. |
