Analysis Of Coupling Influence And Coordinated Operation Method In Regional Integrated Energy System

The regional integrated energy system containing natural gas,wind energy and other energy sources is an important way to realize the cascade utilization of energy and the coordinated and complementary application of multiple energy sources.However,the complex structure of the regional integrated energy system,the large time scale span,the close coupling relationship between multiple types of energy,the interaction between the components of the same energy subsystem and the interaction between different energy subsystems make it difficult to mathematically model the system dynamics accurately.It is difficult to balance the efficiency and accuracy of dynamic simulation.At the same time,in the actual operation of the system,the dynamic characteristics and coupling influence mechanism of different energy flows are not yet clear,which makes it difficult to ensure the coordinated operation ability and energy supply efficiency of the system.Therefore,the complementary cooperation and coordinated operation of multi-energy systems based on dynamic models are studied.It is of great significance to realize the optimal operation of multiple energy sources.This dissertation takes the electricity-gas-heat integrated energy system as the research object,and conducts in-depth research from the perspectives of the dynamic model and its reduced-order simplification method,the coupling analysis of disturbance effects,and the coordinated operation method of the whole system,so as to realize the optimization and efficiency of the integrated energy system.Firstly,a singular perturbation dynamic reduced order model of regional integrated energy system is proposed.On the basis of the complete full-order dynamic model of regional integrated energy system,a high-precision model reduced order method based on singular perturbation theory is given.Practical research requires that a reduced-order model suitable for the research perspective of short time scale and the perspective of long time scale research should be constructed respectively.Secondly,considering the problem of unclear influence of disturbance in natural gas system,based on the reduced-order model under long time scale,the propagation mechanism of disturbance in the whole system is revealed.Considering the problem that the influence of power system disturbance in the whole sy stem is not clear,the propagation mechanism of the disturbance is analyzed based on a reduced-order model under the short time scale.And the validity of the coupled influence analysis is verified by simulation.Finally,an optimal coordinated operation method of the regional integrated energy system considering the electric-heat coupling and demand response is proposed.From the operation control level,based on the reduced-order model,an optimal control strategy aiming at the lowest operating cost is established,and the electric-heat integrated demand response is introduced.In order to make full use of the control value of the demand side,and analyze the change of the output of each unit in the system due to the coupling effect in the case of insufficient gas supply.The order reduction and simplification method of regional integrated energy system based on singular perturbation theory proposed in this thesis can be used to accurately describe the dynamic change trajectory of system variables under various working conditions,and solve the problem caused by the high order and low simulation efficiency of regional integrated energy system dynamic model.On this basis,this thesis uses the established model to capture the dynamic characteristics of each link of the system,and realizes the quantitative analysis of the coupling effect on the entire system when the subsystem is disturbed.At the same time,this thesis applies the reduced-order model to the design of the coordinated operation scheme,making full use of the conversion and transmission characteristics between different energy sources to improve the flexibility of system operation,and promoting the efficient use of energy.It solves the difficulty of optimal control design caused by the large time scale span and complex coupling relationship of the integrated energy system.