Research On Planning And Operation Optimization Of Integrated Energy System Based On Alternating Direction Multiplier Method

With the continuous development of various energy conversion and coupling technologies,electricity-centric multi-energy systems have developed rapidly in recent years.At the same time,information and communication technology has continued to improve.Its combination with the energy system not only brings the advantages of convenience,but also increases the complexity of the joint system,and brings new challenges to the analysis of the cyber coupling energy system.Aiming at the integrated energy system with electric power and natural gas as the main body,this paper adopts the Alternative Direction Multiplier Method(ADMM)as the optimal solution method to study the problem of multi-scenario planning and optimal operation under cyber coupling.The main research content and contributions of this paper are as follows:(1)For the long-term multi-scenario planning optimization problem of the electric-gas hybrid system,a problem model considering the dynamic characteristics of natural gas,the uncertainty of renewable energy and the losses of energy storage life is constructed.Furthermore,a decoupling computing framework is proposed based on ADMM,the original problem is decomposed to planning and operation sub-problems in each scenario,and iteratively obtain the optimal solution.Case study shows that the framework effectively avoids the high complexity of the planning problem in centralized methods,and has good performance in scalability.In addition,this paper also considers the issue of distribution network operation flexibility during the planning process,and discusses the positive role of natural gas network in improving operation flexibility through sensitivity analysis.(2)Regarding the resilience of the electricity-gas hybrid system under cyber coupling,this paper firstly describes the relationship between the information system and the energy system in terms of control,energy supply,and network topology connections.Moreover,with the consideration of dynamic characteristic in natural gas network and the coupling relationship between physical layer and information layer,an optimization analysis model for the resilience of the cyber physical coupling system based on the directed multi-commodity flow is constructed.On this basis,a two-step optimization strategy for resilience and economy is proposed.Firstly,the reconfiguration is conducted with the goal of load losses,and then the improved ADMM is used for distributed solution based on the determined network.Finally,the effectiveness of the proposed model and method is verified by simulations.(3)For the cyber coupling energy system optimized by ADMM under harsh communication conditions,this paper studies the information interaction mode of Gauss-Seidel Alternative Direction Multiplier Method(GS-ADMM),Jacobian Alternative Direction Multiplier Method(J-ADMM)and Proximal Jacobian Alternative Direction Multiplier Method(PJ-ADMM).The differences are compared through case studies based on economic optimization of electric-gas hybrid system.At the same time,the ADMM optimization analysis under the harsh communication environment with high packet loss is carried out.Strategies such as skipping,previous value iteration,and predictive correction strategy are adopted to improve the optimization robustness of the algorithm in the packet loss environment,and the effectiveness of the proposed strategies is verified by simulations.