Research On Expansion Planning Of Electric-Gas Integrated Energy System Based On Maximum Energy Supply Capacity

As people pay more attention to environmental issues and countries seek to develop clean and efficient energy systems,the "Energy Internet" comes into being.Among them,the new generation energy system with the power grid as the core is closely linked with the power network and the natural gas network through gas unit,power-to-gas and other coupling equipment,which is called the power-gas integrated energy system.In the power system,the maximum power supply capacity is an important indicator to show the reliability of the system,which can more accurately analyze the power supply level and load demand level of the equipment.However,most of the researches on the maximum energy supply capacity of the power-gas integrated energy system remain in the steady-state model of natural gas system,without considering the operation of the power-to-gas equipment.And how to apply the maximum energy supply capacity to the system planning problem also remains to be explored.In view of the above problems,this paper considers the dynamic storage of natural gas,the two-way coupling of gas turbine and power-to-gas,and studies the maximum energy supply capacity of the power-gas integrated energy system and the expansion planning of the power-gas integrated energy system.The main research contents are as follows:Firstly,the basic framework of the power-gas integrated energy system is described,and the model of the natural gas system,the model of the power-to-gas device and the model of the gas turbine considering the dynamic pipe storage are given.The solution method of the model is discussed,and the CPLEX solver and YALMIP modeling language used in MATLAB software are introduced,which lays a foundation for the following research.Secondly,a maximum energy supply capacity model considering the power to gas technology and the dynamic storage of natural gas is proposed.Firstly,considering the constraints of natural gas dynamic pipeline storage and power-to-gas conversion,a model with the maximum energy supply capacity of the power system in the state of N-1 as the objective function is established.The nonlinear part of the model is linearized by incremental linearization,and the model is transformed into a mixed integer linear programming form which is easy to solve.Use Yalmip language to program and call the CPLEX solver to solve.The feasibility and effectiveness of the proposed model are verified by the simulation analysis of a numerical example.Finally,an extended programming model considering the margin index of the energy storage device and the electric-gas integrated energy system is proposed.Firstly,the energy storage device model was established,and the maximum energy supply capacity margin index of the electric-gas integrated energy system was defined.Then,taking into account the output constraints of each device in the integrated energy system and satisfying the maximum energy supply capacity margin required by the system,an extended programming model with the minimum planning cost as the objective function is established.Finally,through a simulation example,it is divided into three scenarios,and the influence of energy storage device and maximum energy supply capacity margin index on the planning results is discussed,which verifies the rationality of the model.