Research On Energy Coordination And Optimization Of Integrated Electricity-Gas System Based On Multi-Agent

As electricity-gas coupling technique continue developing,integrated electricity-gas system has been paid much attention by governments,academic institutions and enterprises,and it has gradually become the mainstream development form of multi-energy utilization system.Integrated electricity-gas system has many kinds of equipment,complex energy-flow coupling relationship and obvious distributed energy structure,when traditional methods are used to solve the task of energy coordination and optimization,there are many limitations in system modeling,distributed strategy execution,data and information interaction,etc.,so it is difficult to effectively realize the cascade complementarity and collaborative op timization of electricity and natural gas.In recent years,the continuous development of multi-agent technology provides a new idea for energy coordination optimization of integrated electricity-gas system,this paper took advantage of the central-distributed intelligence characteristics of multi-agent system and gave full play to the agent autonomy,social ability,reactivity and initiative characteristics to reconstruct the model of integrated electricity-gas system,and conducted research on its energy coordination optimization.Firstly,based on the typical architecture of integrated electricity-gas system,the energy circulation model of the system,which taken the basic unit of energy circulation and the energy transmission network as the main physical links,was built.Further,based on the economic characteristics of the capacity unit,the charge characteristics of the energy storage unit,the comprehensive demand response characteristics of the multi-energy users and the energy conversion characteristics of the coupling equipment,the mathematical models of all kinds of basic energy circulation units were built,based on the energy flow characteristics of power lines and natural gas pipeline network,a linearized power flow model of energy transmission network was constructed by piecewise linearization method.Secondly,the energy flow model of integrated electricity-gas system was reconstructed by using the multi-agent technology.A layered multi-agent system structural model,which was composed of unit-layer agent,node-layer agent and system-layer agent,was proposed,an interactive communication architecture model of multi-agent system based on contract network protocol was established,thus,the structure and communication foundation for the application of multi-agent technology in integrated electricity-gas system was laid.The specific operation logic and strategy of agents at each level are defined,and a central-distributed energy coordination optimization strategy is proposed,which combines the distributed local energy coordination optimization method of node layer agent and the global centralized energy coordination optimization method of system layer agentThirdly,the energy coordination optimization strategy of hierarchical multi-agent system was constructed.The communication contents and operation strategies of the agents at each level in the multi-agent system were defined,and a weighted adjustable energy coordination optimization strategy was proposed,which combines the distributed energy coordination optimization meth od of the node layer agent and the centralized energy coordination optimization method of the system layer agent.Finally,the JADE software platform was used to design the layered multi-agent system.An integrated electricity-gas system coupled by improved IEEE5-node power system and 7-node natural gas system was built as the simulation example to verify the proposed method,the results showed that the proposed method can operate stably in different simulation environments,and realized the energy optimization of integrated electricity-gas system.