Operation Optimization And Benefit Evaluation Of Regional Multi-energy Complementary System With Energy Storage

Energy is the driving force and foundation of social and economic development.With the rapid development of China’s economy,the energy consumption structure dominated by fossil energy makes the current situation of energy shortage and environmental pollution increasingly severe.Promoting the application of renewable energy resources,improving the utilization efficiency of all kinds of energy and reducing the consumption of traditional fossil energy have become the inevitable choice to solve the contradiction between social and economic development and energy shortage.The multi-energy complementary system takes the power system as the core,contains various renewable energy sources and energy storage units,and has the characteristics of economy,environmental protection,flexibility and high efficiency.With the development of distributed equipment and energy conversion technology,multienergy complementary systems have broad application prospects.As a key component of the multi-energy complementary system,energy storage can effectively alleviate the contradiction between supply and demand between energy production and consumption.Mining the benefits of energy storage can improve the competitiveness of the multi-energy complementary system.In view of this,it is of great importance for the development of multi-energy complementary systems to carry out operation optimization and benefit evaluation of multi-energy complementary systems,further excavate energy storage benefits,and analyze the impact of energy storage modes on the comprehensive benefits of multi-energy complementary systems.The main contents of this thesis are as follows:1)Modeling and solving of multi-energy complementary system is the foundation and premise to realize operation optimization and benefit evaluation.According to the typical multienergy complementary operation scenario of the park,considering the diversity of main equipment and the complexity of energy flow in the multi-energy complementary system,the operation characteristics and energy conversion relationship are analyzed,and the operation characteristic model of the multi-energy complementary system including energy production,energy conversion and energy storage equipment is established,which lays a foundation for the following work.2)In order to further tap the energy storage benefits and give full play to the role of storage batteries in the operation optimization of multi-energy complementary systems,based on the typical operation mode and operation characteristics of multi-energy complementary systems,taking into account the system energy balance constraints,equipment operation and coupling constraints,network constraints,etc.A dual-level optimization model of multi-energy complementary systems is established,which takes into account the market benefits of power storage auxiliary services.According to the changes of the real-time electricity price and the load shortage,the optimal scheduling strategy of the system and the optimal charging and discharging state of the battery are formulated.The influence of different battery control strategies on the system economy is compared and analyzed by an example.3)Aiming at the problem of comprehensive benefit evaluation of multi-energy complementary system,an evaluation index system of comprehensive benefit of multi-energy complementary system with energy storage is constructed from five angles of economic cost,energy storage benefit,environmental benefit,energy consumption level and system reliability.Fuzzy algorithm and interval analytic hierarchy process are used to normalize and calculate the weight of each index,and a comprehensive benefit evaluation method of multi-energy complementary system is proposed.4)Different energy storage modes will affect the comprehensive benefits of multi-energy complementary system operation.It is very important to realize the optimal operation of the system based on reasonable energy storage modes.Therefore,the energy storage modes of multi-energy complementary systems are analyzed,and the energy storage modes are divided into seven types according to the energy storage types.Considering the influence of energy transmission loss,system equipment and transmission capacity limitation,an optimal scheduling model for multi-energy complementary system is established.By comparing the comprehensive benefit evaluation values under different energy storage modes,the paper analyzes the effects of different energy storage modes on the system’s benefits at different levels and the interaction between energy storage devices,and discusses the effects of renewable energy permeability and energy storage capacity on the comprehensive benefits of multi-energy complementary systems.