Research On Energy Sharing Pattern Taking Into Account Mobile Energy Storage And Its Application In Island Microgrids

With the maturity of distributed new energy generation and energy storage technologies,many prosumers and mobile energy storage resources,such as electric vehicles(EV),are emerging on the user side.Various resources’ complementary advantages and synergistic benefits are expected to be exploited to achieve a multi-win solution if these resources from production,consumption,and energy storage can be effectively integrated to realize energy sharing.In particular,mobile energy storage resources with space-time transfer characteristics are promising to break through the inherent constraints of power lines,build energy collection-transportation-release links,and realize energy sharing among entities with weak or no electrical connections.However,research on energy sharing considering mobile energy storage is relatively rare,and many theoretical and technical problems on this topic need to be overcome.This thesis selects island microgrids as the research object and covers the following two types of typical application scenarios regarding energy-sharing: 1)Daily operation scenario:transmission congestion occurs within the island microgrid,and submarine cables cannot be laid to link the microgrids located on different distant islands;2)Emergency operation scenario: both intra-island and inter-island power lines may suffer physical damage,leading to isolated regions.To cope with the above problems regarding energy sharing,mobile energy storage such as EVs and electric passenger vessels(EPV)can be exploited to enhance the inter-temporal connection among the island microgrids,which is expected to realize daily and emergency energy sharing among multiple entities,and improve the operation economy and emergency response capability of such entities.To this end,this thesis first explores the typical application patterns of energy sharing considering mobile energy storage and then takes the island microgrids as the research object,focusing on daily energy sharing of multiple entities within the island microgrid considering the demand response characteristics of EVs,daily energy sharing of multi-island microgrids based on integrated battery swapping mode,emergency energy sharing within the island microgrid considering the space-time transfer characteristics of EVs,and emergency energy sharing of the multi-island microgrids based on dual mode switching of EPVs.The main contents are included as follows:In terms of the architecture and typical application patterns of energy sharing considering mobile energy storage,the concept of energy sharing considering mobile energy storage and its architecture is first defined,and two typical application patterns are proposed: the peer-to-peer interaction pattern and the integrated collaboration pattern.Subsequently,the refined models of mobile energy storage,microgrids,and new energy generations are established,and the optimization methods under different application patterns are analyzed.Then,case studies through arithmetic simulation are carried out,and it is verified that incorporating mobile energy storage can effectively improve the energy sharing efficiency of prosumers and safeguard the smooth operation of critical loads.Finally,the typical application scenarios of the energy sharing application patterns are initially explored.In terms of daily energy sharing of multiple entities within the island microgrid considering the demand response characteristics of EVs,aiming at addressing the problem of energy sharing being restricted due to transmission congestion,the concept of using EV fast-charging stations to adjust the load curve and thereby promote energy sharing among prosumers is proposed.Then,a master-slave game approach is used to simulate the demand response of EVs,and a fast charging station linear load model is constructed.On this basis,a distributed energy trading strategy for multiple entities within the island microgrid is proposed considering power flow constraints.Subsequently,a multi-entities benefit allocation mechanism is designed based on the asymmetric Nash bargaining theory,among which the bargaining power is reasonably evaluated according to the production and consumption of energy behaviors.The simulation results show that the proposed strategy can steer the EV charging load orderly,promote new energy consumption in the neighborhood,and realize the collective benefit of multiple entities.In terms of daily energy sharing of multi-island microgrids based on integrated battery swapping mode,aiming to deal with the problem of being unable to lay submarine cables between islands,a multi-island microgrids energy sharing architecture based on the integrated battery swapping mode is proposed at first.Secondly,the coupling properties of traffic flow and energy flow of battery swapping vessels and modular energy storage batteries are analyzed to construct a scheduling decision model for the battery-swapping system.Then,a robust energy-sharing model of multi-island microgrids is developed to minimize the operating cost by considering the uncertainty in the new energy power and using the information gap decision theory.Finally,the feasibility and economy of the proposed energy sharing strategy based on the battery-swapping mode are verified with extensive simulation tests.In terms of emergency energy sharing within the island microgrid considering the space-time transfer characteristics of EVs,a pattern of integrated emergency energy sharing within the island microgrid using EVs is first proposed.Secondly,an emergency incentive mechanism for EV that combines basic and performance benefits is designed to attract EV owners to participate in emergency scheduling.Then,the EV clustering scheduling model is constructed by discretizing battery energy and power,sacrificing model accuracy to some extent for sufficient solving speed.Moreover,the island microgrid’s emergency real-time energy sharing strategy with power flow constraints are proposed.Finally,by using an extensive arithmetic simulation test,the proposed strategy is verified to improve the efficiency of emergency energy sharing within the island microgrid and ensure the safe operation of critical loadsIn terms of emergency energy sharing of the multi-island microgrids based on dual mode switching of EPVs,a multi-island microgrids emergency energy sharing pattern with EPVs as a supplementary transmission mode is proposed to address the problem of inefficient inter-island energy transmission due to the damage of submarine cables.Secondly,the scheduling decision model of EPV is constructed by considering the dual modes of inter-island public transportation and energy transmission.Then,using EPV as the virtual agent,a bi-level distributed emergency energy sharing model of "multi-island microgrids-EPV company-EPV" is constructed and solved efficiently by the adaptive alternating direction multiplier method.Finally,the superiority of the proposed multi-island microgrids emergency energy sharing strategy is verified through the simulation of arithmetic cases.