Research On Energy Management Strategies For The Microgrid In A Smart Grid

With the development of smart grid concept,environment friendliness,high energy-using efficiency,and sustainable development have become important targets for power network construction.Recently,microgrid has been an important symbol of smart grid realization and application.It can efficiently integrate resources on both supply and demand sides,especially the distributed renewable energy,improve energy utilization,and reduce the system operation cost.However,some scientific problems need to be solved in the energy management of a microgrid.Firstly,the intermittence of distributed renewable power supply and the uncertainty of the demand side,which are not friendly to the stable operation of a microgrid system.Secondly,owing to the interest interaction among microgrid,main grid,and users,energy management is a complex energy optimization scheduling problem with high dimension,multi-variables,and multiconstraints.Thirdly,the energy Internet enables all subjects with the characteristics of autonomy and self-discipline,but there is no guaranteed management strategy.In this context,this thesis focuses on the energy management strategy of the microgrid in a smart grid.The detailed research contents and contributions are as follows:(1)Research on the energy management strategy for the microgrid considering the uncertain environment:Taking the schedulability of the microgrid energy management system into consideration,and a cooperative frequency regulation management strategy with the model predictive control strategy and a dynamic energy interaction scheme is proposed.Then,the operation stability of the microgrid system in the uncertain environment is improved.(2)Research on the energy management strategy for the microgrid considering the demand side building user interaction:An optimal,reliable,and secure demand-side interaction model is constructed.By participating in the demand response,users actively schedule the shifting power load and reduce the cuttable thermal load according to the price information.Then,the purpose of the peak load shifting is achieved and the profitability of each user is also improved.All transactions are conducted anonymously guaranteed by blockchain technologies without privacy leakage.All information interaction is conducted and stored in a blockchain network.The data maintained by all users are transparency,traceability,and tamper-proof.(3)Research on the energy management strategy for the microgrid considering the interaction of the supply side and demand side:The information security,trust-building,and optimal energy scheduling management in the leader-follower structure are achieved.Stackelberg game is used to describe the dynamic process of the interaction between the supply side and demand side effectively.Blockchain technologies are utilized to protect the privacy and build trust between users in the leader-follower structure.The anonymous operation can avoid the privacy disclosure of each user.The smart contract applies iteration optimization solving to ensure trust and fairness without third-party authorities.The data verification is enabled to verify the execution of the optimal electricity schedule of all users without jeopardizing privacy.All data is the consensus of all users,which reduces external malicious attacks,such as spurious data injection.(4)Research on the energy management strategy for the microgrid considering multi-resources and multi-agents interaction:The communication resource and power resource sharing of multiple microgrids are both considered.Stackelberg game is used to describe the dynamic process of interaction between the communication operator and multiple microgrids effectively.The operator as the leader maximizes the profit by setting the price of communication services.Meanwhile,a cooperative alliance formed by the multiple microgrids is the follower,who actively regulates power-sharing strategy in response to the strategy set by the operator.Owing to the switching policy of each server,the upper programming problem is a complex mixed-integer nonlinear programming problem,which can not be well-solved by existing methods.Hence,the upper programming problem is decoupled into a mixed-integer quadratic programming subproblem and a nonlinear programming subproblem,and an iterative optimization algorithm is proposed to obtain the optimization energy management strategy.