Resilience Assessment Of Integrated Gas-electric System Under Extreme Event

Due to the increase of environmental pollution and the limitation of traditional power system in energy supply,people begin to pay attention to integrated energy system which can connect many kinds of energy sources.Because the power network and gas network are more mature in the power supply network and energy supply technology,it is of great significance to study the integrated gas-electric energy system formed by the power network and gas network.In addition,when extreme disasters such as earthquakes and typhoons occur,they can cause extensive damage not only to the power grid,but also to integrated gas-electric system.At present there are some researches on the elastic evaluation of distribution network but few researches on the elastic evaluation of the background of integrated energy system.Therefore,in this paper,the research object is the electro-gas integrated energy system,which includes P2 G technology to evaluate the elasticity of the integrated energy system under extreme disasters.The main research contents of this paper include:1)Modeling and simulation of integrated gas-electric system with more complex network coupling.Firstly,the mathematical model of gas pipeline network,distribution network and coupling device is established.Then,on the basis of the traditional constraints,considering that the coupling of networks is more complicated,the flow of mixed networks is calculated by using the maximum renewable energy utilization as the target function.Finally,Matlab is used to simulate and verify two kinds of integrated gas-electric system with different number of nodes.The simulation results show that the constraints of complex network coupling are better suited to the practical situation of P2 G integrated energy system.2)Fault propagation analysis of IGES based on SIR and SIS infectious disease models.Firstly,by analogy with infectious disease model,the intensity of network disturbance propagation is defined,and the infectious disease model conforming to grid and gas network is established.Then,the complex network theory is used to analyze the topology of the integrated energy system,and the stochastic matrix theory is used to analyze the correlation of the network data.Finally,based on the topology of energy network,a dynamic model of system disturbance propagation is established,and the propagation behavior of power grid and natural gas network disturbance is predicted.The simulation results prove the validity of the infectious disease model in disturbance propagation and provide theoretical basis for the disturbance propagation analysis of the integrated energy system.3)Resilience assessment of integrated gas-electric system considering the side of natural gas networks in extreme disasters.Firstly,based on the traditional elastic attack model,the scope and harmfulness of node attack are expanded,and the system failure scene is generated by the fault node propagation strategy.Then,the model of integrated gas-electric system in gas network disturbed by extreme events is established.The system uses gas turbine to supply load and calculates load deficit in isolated island according to the optimal tangent load model.Based on Monte Carlo simulation,the elasticity of distribution network with meter-gas interconnection is evaluated by using the missing area of distribution network load curve as elastic index.Finally,the simulation of IEEE 39 power network and gas network of 20 nodes is carried out,and the elastic evaluation results of the electro-gas integrated energy system are analyzed.