Communication-dependent and software-based distributed energy resources(DERs)are extensively integrated into modern microgrids,providing extensive benefits such as increased distributed controllability,scalability,and...Communication-dependent and software-based distributed energy resources(DERs)are extensively integrated into modern microgrids,providing extensive benefits such as increased distributed controllability,scalability,and observability.However,malicious cyber-attackers can exploit various potential vulnerabilities.In this study,a programmable adaptive security scanning(PASS)approach is presented to protect DER inverters against various power-bot attacks.Specifically,three different types of attacks,namely controller manipulation,replay,and injection attacks,are considered.This approach employs both software-defined networking technique and a novel coordinated detection method capable of enabling programmable and scalable networked microgrids(NMs)in an ultra-resilient,time-saving,and autonomous manner.The coordinated detection method efficiently identifies the location and type of power-bot attacks without disrupting normal NM operations.Extensive simulation results validate the efficacy and practicality of the PASS for securing NMs.展开更多
This paper proposes a multi-agent cooperative operation optimization strategy for regional power grids considering the uncertainty of renewable energy output and flexibility of electric vehicle(EV)scheduling,which not...This paper proposes a multi-agent cooperative operation optimization strategy for regional power grids considering the uncertainty of renewable energy output and flexibility of electric vehicle(EV)scheduling,which not only improves the economy of networked microgrid(NMG)scheduling but also reduces the impact on active distribution network(ADN).EV condition matrix and model of the adjustable charge-anddischarge capacity of the EV may be built up by simulating the trip rule of an EV using the driving behavior of the vehicle model.In the day-ahead stage,by taking into account NMG operating cost,distribution network loss,and EV owners’payment cost,a multi-objective optimal scheduling model is developed,and the day-ahead scheduling contract for EV is obtained.Generative Adversarial Network(GAN)generates a significant number of intraday scenarios of photovoltaic(PV),load,and EV based on historical scheduling data as training data for the intra-day scheduling model multi-agent PPO(MAPPO).In the intra-day scheduling stage,intra-day ultra-short-term forecast data is input into the intra-day scheduling model,and the trained multi-agent model realizes NMG distributed real-time optimal scheduling.Finally,the economy and effectiveness of the proposed strategy are verified by Day-after optimal scheduling results.展开更多
This paper proposes a resilient restoration method for low-inertia networked microgrids(NMGs)dominated with inverter-based energy resources(IBERs).First,a frequency dynamics-aware NMG restoration model is developed,in...This paper proposes a resilient restoration method for low-inertia networked microgrids(NMGs)dominated with inverter-based energy resources(IBERs).First,a frequency dynamics-aware NMG restoration model is developed,integrating a unified frequency control response framework that accommodates various control strategies while ensuring the system stability during restoration.Case studies for a low-inertia NMG demonstrate the effectiveness of the proposed method.Numerical results show that different IBER control methods could have a significant impact on restoration efficiency and economic losses.Additionally,strict frequency security requirements can predominantly increase the restoration time,calling for a critical trade-off between maintaining network security margins and restoration time for enhancing the resilience of low-inertia NMGs dominated with IBERs.展开更多
The proliferation of distributed and renewable energy resources introduces additional operational challenges to power distribution systems.Transactive energy management,which allows networked neighborhood communities ...The proliferation of distributed and renewable energy resources introduces additional operational challenges to power distribution systems.Transactive energy management,which allows networked neighborhood communities and houses to trade energy,is expected to be developed as an effective method for accommodating additional uncertainties and security mandates pertaining to distributed energy resources.This paper proposes and analyzes a two-layer transactive energy market in which houses in networked neighborhood community microgrids will trade energy in respective market layers.This paper studies the blockchain applications to satisfy socioeconomic and technological concerns of secure transactive energy management in a two-level power distribution system.The numerical results for practical networked microgrids located at IllinoisTech−Bronzeville in Chicago illustrate the validity of the proposed blockchain-based transactive energy management for devising a distributed,scalable,efficient,and cybersecured power grid operation.The conclusion of the paper summarizes the prospects for blockchain applications to transactive energy management in power distribution systems.展开更多
The locations of marine ranch and its surrounding islands are far away from the mainland,so the cost is too high to keep power supply by laying submarine cables from the mainland.Therefore,it is necessary to build a l...The locations of marine ranch and its surrounding islands are far away from the mainland,so the cost is too high to keep power supply by laying submarine cables from the mainland.Therefore,it is necessary to build a land-sea relay networked microgrids with high propor-tion of renewable energy,which is able to provide multi-energy complementary and reli-able power for marine ranch and its surrounding islands.It is noteworthy that the networked microgrids is a typical cyber-physical system.In order to deeply reveal the cyber physical fusion characteristics of fishery networked microgrids,the morphology and key techniques of fishery networked microgrids are summarized from two aspects:physical system and cyber system.And the interactions of cyber and physical system are described,including the support from cyber system for the physical system as state perception and control,and the power support from physical system for cyber system.Based on the above interactions,the related research on coupling analysis of cyber-physical system is summa-rized.Finally,some urgently studied problems have been looked forward to in fishery net-worked microgrids cyber-physical system.展开更多
In this work,a PSCAD electromagnetic model is constructed for a microgrid community.It consists of three microgrids networked through the medium voltage(MV)distribution system as a practical case of the distributed re...In this work,a PSCAD electromagnetic model is constructed for a microgrid community.It consists of three microgrids networked through the medium voltage(MV)distribution system as a practical case of the distributed resource island systems of IEEE Standard 1547.4.Typical operational scenarios are then simulated for both grid connected and islanded mode of operation.The study outcomes demonstrate the operational feasibility of networked microgrids in electrical distribution systems and the effectiveness of common droop controls in facilitating energy transaction of the microgrids and maintaining voltage and frequency stabilities under normal network disturbances.This investigation is significant in that it addresses the needs and issues arising from primary controls for facilitating the energy transactions of secondary and tertiary controls in the hierarchical control strategy of networked microgrids in the MV distribution system.Future studies of the secondary and tertiary control algorithms will need to incorporate new requirements for ensuring distribution system voltage and frequency securities.展开更多
Microgrid(MG)is a small-scale,self-sufficient power system that accommodates various distributed energy resources(DERs),controllable loads,and future distribution systems.Networked microgrids(NMGs)are clusters of MGs,...Microgrid(MG)is a small-scale,self-sufficient power system that accommodates various distributed energy resources(DERs),controllable loads,and future distribution systems.Networked microgrids(NMGs)are clusters of MGs,which are physically interconnected and functionally coordinated to enhance distribution systems in terms of economics,resilience,and reliability.This paper introduces the architecture and control of NMGs including nanogrid(NG)and MG.To accommodate variable DERs in NMGs,master and distributed control strategies are adopted to manage the high penetration of DERs,where master control focuses on economic operation,while distributed control focuses on reliability and resilience through active power sharing and voltage and frequency regulation.The initial practices of NG,MG,and NMG in the networked Illinois Institute of Technology(IIT)campus microgrid(ICM)and Bronzeville community microgrid(BCM)in the U.S.are presented.The applications of the master and distributed control strategies are illustrated for the networked ICM-BCM to show their benefits to economics,resilience,and reliability.展开更多
Networked microgrids(NMGs)are critical in theaccommodation of distributed renewable energy.However,theexisting centralized state estimation(SE)cannot meet the demandsof NMGs in distributed energy management.The curren...Networked microgrids(NMGs)are critical in theaccommodation of distributed renewable energy.However,theexisting centralized state estimation(SE)cannot meet the demandsof NMGs in distributed energy management.The currentestimator is also not robust against bad data.This study introducesthe concepts of relative error to construct an improvedrobust SE(IRSE)optimization model with mixed-integer nonlinearprogramming(MINLP)that overcomes the disadvantage ofinaccurate results derived from different measurements whenthe same tolerance range is considered in the robust SE(RSE).To improve the computation efficiency of the IRSE optimizationmodel,the number of binary variables is reduced based on theprojection statistics and normalized residual methods,which effectivelyavoid the problem of slow convergence or divergenceof the algorithm caused by too many integer variables.Finally,an embedded consensus alternating direction of multiplier method(ADMM)distribution algorithm based on outer approximation(OA)is proposed to solve the IRSE optimization model.This algorithm can accurately detect bad data and obtain SE resultsthat communicate only the boundary coupling informationwith neighbors.Numerical tests show that the proposed algorithmeffectively detects bad data,obtains more accurate SE results,and ensures the protection of private information in all microgrids.展开更多
Renewable energy resources play an important role in the realization of the carbon neutrality.The microgrid can efficiently integrate numerous renewable energy systems into power distribution systems to realize power ...Renewable energy resources play an important role in the realization of the carbon neutrality.The microgrid can efficiently integrate numerous renewable energy systems into power distribution systems to realize power supply resiliency and environmental affinity.This paper reviews the current trend of microgrid and networked microgrid technologies worldwide,particularly in Japan,including the Flexible,Reliable,and Intelligent Energy Delivery System(FRIENDS)and some other examples of the networked microgrid.Some recent digitalized control functions of the microgrid and related systems are also introduced.展开更多
The islands and offshore fish farming platforms in the deep sea can form a land-sea net-worked fishery microgrids to realize the complementary supply of energy.The fishery microgrid contains a high proportion of renew...The islands and offshore fish farming platforms in the deep sea can form a land-sea net-worked fishery microgrids to realize the complementary supply of energy.The fishery microgrid contains a high proportion of renewable energy sources such as wind,solar and waves,and mixed AC and DC loads such as feed machine,energy storage,and fishery robot.Due to the harsh operating environment,the possibility of equipment damage increases,and the requirements for system stability are higher.In this paper,firstly,the definition of transient stability of land-sea networked fishery microgrids is given.Then,the key features of the fishery microgrid is introduced,and the influence of the micro-source interface type,control strategy,current limiting mechanism and load characteristics on the transient stability is expounded.The definition of power Angle of fishery microgrid and the characterization of instability system are given.Next,the research trends of tran-sient stability are sorted out,evaluated and discussed from two aspects:approaches of transient stability analysis and methods to improve transient stability.Finally,the key issues that need to be solved urgently in the research on the transient stability of the land-sea networked fishery microgrids are summarized,and the relevant research direc-tions are prospected.展开更多
As a growing number of microgrids(MGs)has been integrated into the modern power grids,the interconnection and applicable cooperation among multiple MGs motivate the development of networked MGs.Dynamic MGs,as an advan...As a growing number of microgrids(MGs)has been integrated into the modern power grids,the interconnection and applicable cooperation among multiple MGs motivate the development of networked MGs.Dynamic MGs,as an advanced networked MGs structure,can not only integrate multiple MGs into the distribution system but also fulfill the requested system network reconfiguration with improved flexibility.A general distributed control approach for networked MGs is reviewed.A distributed control framework for dynamic MGs operation is developed,along with an extensible architecture with considerations of large-scale distributed energy resources(DERs)integration.A scalable small-signal stability analysis is conducted per the proposed distributed control strategies and the conditions under which the system is exponentially stable are derived.At last,the effectiveness of the proposed control framework and stability analysis are verified using a 6-bus test feeder.展开更多
Design and selection of advanced protection schemes have become essential for reliable and secure operation of networked microgrids.Various protection schemes that allow correct operation of microgrids have been propo...Design and selection of advanced protection schemes have become essential for reliable and secure operation of networked microgrids.Various protection schemes that allow correct operation of microgrids have been proposed for individual systems in different topologies and connections.Nevertheless,protection schemes for networked microgrids are still in devel-opment,and further research is required to design and operate advanced protection in interconnected systems.Interconnection of these microgrids in different nodes with various intercon-nection technologies increases fault occurrence and complicates protection operation.This paper aims to point out challenges in developing protection for networked microgrids,potential solutions,and research areas that need to be addressed for their development.First,this article presents a systematic analysis of different microgrid clusters proposed since 2016,including several architectures of networked microgrids,operation modes,components,and utilization of renewable sources,which have not been widely explored in previous review papers.Second,the paper presents a discussion on protection systems currently available for microgrid clusters,current challenges,and solutions that have been proposed for these systems.Finally,it discusses the trend of protection schemes in networked microgrids and presents some conclusions related to implementation.IndexTerms—Adaptive eprotection,microgrid cluster,microgrid,multiple microgrid,networked microgrid,real-time simulation,smart grid.展开更多
This paper focuses on the distributed control prob-lem in a networked microgrid(NMG)with heterogeneous ener-gy storage units(HESUs)in the environment considering multi-ple types of time delays,which include the state,...This paper focuses on the distributed control prob-lem in a networked microgrid(NMG)with heterogeneous ener-gy storage units(HESUs)in the environment considering multi-ple types of time delays,which include the state,input,and communication delays.To address this problem,a state feed-back control(SFC)strategy based on nested predictor is pro-posed to mitigate the influence of multiple types of time delays.First,a distributed control method founded upon voltage ob-server is developed,which can realize proportional power distri-bution according to the state of charge(SOC)of the HESUs,while adjusting the average voltage of the point of common cou-pling(PCC)bus in the NMG to its rated value.Then,consider-ing that there exists steady-state error resulting from the initial value of the observer and impact of time delays,an SFC strate-gy is proposed to further improve the robustness of the NMG against time delays.Finally,the experimental results demon-strate that the proposed distributed control method is capable of fully compensating for the state,input,and communication delay.Moreover,the NMG exhibits remarkable resistance to multiple types of time delays,which has higher reliability and robustness.展开更多
Microgrids are gaining popularity by facilitating distributed energy resources(DERs)and forming essential consumer/prosumer centric integrated energy systems.Integration,coordination and control of multiple DERs and m...Microgrids are gaining popularity by facilitating distributed energy resources(DERs)and forming essential consumer/prosumer centric integrated energy systems.Integration,coordination and control of multiple DERs and managing the energy transition in this environment is a strenuous task.Classical control techniques are not enough to support dynamic microgrid environments.Implementation of Artificial Intelligence(AI)techniques seems to be a promising solution to enhance the control and operation of microgrids in future smart grid networks.Therefore,this paper briefly reviews the control architectures,existing conventional controlling techniques,their drawbacks,the need for intelligent controllers and then extensively reviews the possibility of AI implementation in different control structures with a special focus on the hierarchical control layers.This paper also investigates the AI-based control strategies in networked/interconnected/multi-microgrids environments.It concludes with the summary and future scopes of AI implementation in hierarchical control layers and structures including single and networked microgrids environments.展开更多
In this paper, we elaborate a new strategy based on cooperative game theory models to encourage and manage the interactions in a MicroGrid network. The proposed strategy optimizes the cooperation and the energy exchan...In this paper, we elaborate a new strategy based on cooperative game theory models to encourage and manage the interactions in a MicroGrid network. The proposed strategy optimizes the cooperation and the energy exchange in a distributed μGrid network. The strategy consists of a two stage algorithm: Coalition formation algorithm which was specifically created to approximate the optimal set of coalitions that return considerable savings. And the Matching game to manage the energy exchange inside each coalition. The performance of our strategy was verified through simulations. These latter show that the losses can be considerably decreased by the use of the proposed strategy: the rate of the loss reduction can reach up to 20% if the two stages are applied on the network. Moreover, the strategy proved to have a fast convergence which makes it operational for real implemented networks.展开更多
基金This work was supported in part by the National Science Foundation,USA(ECCS-2018492,CNS-2006828,ECCS-2002897,and OIA-2040599).
文摘Communication-dependent and software-based distributed energy resources(DERs)are extensively integrated into modern microgrids,providing extensive benefits such as increased distributed controllability,scalability,and observability.However,malicious cyber-attackers can exploit various potential vulnerabilities.In this study,a programmable adaptive security scanning(PASS)approach is presented to protect DER inverters against various power-bot attacks.Specifically,three different types of attacks,namely controller manipulation,replay,and injection attacks,are considered.This approach employs both software-defined networking technique and a novel coordinated detection method capable of enabling programmable and scalable networked microgrids(NMs)in an ultra-resilient,time-saving,and autonomous manner.The coordinated detection method efficiently identifies the location and type of power-bot attacks without disrupting normal NM operations.Extensive simulation results validate the efficacy and practicality of the PASS for securing NMs.
基金supported by the Science and Technology Project of State Grid Corporation of China(5100-202155320A-0-0-00).
文摘This paper proposes a multi-agent cooperative operation optimization strategy for regional power grids considering the uncertainty of renewable energy output and flexibility of electric vehicle(EV)scheduling,which not only improves the economy of networked microgrid(NMG)scheduling but also reduces the impact on active distribution network(ADN).EV condition matrix and model of the adjustable charge-anddischarge capacity of the EV may be built up by simulating the trip rule of an EV using the driving behavior of the vehicle model.In the day-ahead stage,by taking into account NMG operating cost,distribution network loss,and EV owners’payment cost,a multi-objective optimal scheduling model is developed,and the day-ahead scheduling contract for EV is obtained.Generative Adversarial Network(GAN)generates a significant number of intraday scenarios of photovoltaic(PV),load,and EV based on historical scheduling data as training data for the intra-day scheduling model multi-agent PPO(MAPPO).In the intra-day scheduling stage,intra-day ultra-short-term forecast data is input into the intra-day scheduling model,and the trained multi-agent model realizes NMG distributed real-time optimal scheduling.Finally,the economy and effectiveness of the proposed strategy are verified by Day-after optimal scheduling results.
基金supported by the National Key Research and Development Program of China(No.2022YFB2403100).
文摘This paper proposes a resilient restoration method for low-inertia networked microgrids(NMGs)dominated with inverter-based energy resources(IBERs).First,a frequency dynamics-aware NMG restoration model is developed,integrating a unified frequency control response framework that accommodates various control strategies while ensuring the system stability during restoration.Case studies for a low-inertia NMG demonstrate the effectiveness of the proposed method.Numerical results show that different IBER control methods could have a significant impact on restoration efficiency and economic losses.Additionally,strict frequency security requirements can predominantly increase the restoration time,calling for a critical trade-off between maintaining network security margins and restoration time for enhancing the resilience of low-inertia NMGs dominated with IBERs.
基金funded in part by Grant No.RG-15-135-43 from the Deanship of Scientific Research(DSR)at King Abdulaziz University in Saudi Arabia.
文摘The proliferation of distributed and renewable energy resources introduces additional operational challenges to power distribution systems.Transactive energy management,which allows networked neighborhood communities and houses to trade energy,is expected to be developed as an effective method for accommodating additional uncertainties and security mandates pertaining to distributed energy resources.This paper proposes and analyzes a two-layer transactive energy market in which houses in networked neighborhood community microgrids will trade energy in respective market layers.This paper studies the blockchain applications to satisfy socioeconomic and technological concerns of secure transactive energy management in a two-level power distribution system.The numerical results for practical networked microgrids located at IllinoisTech−Bronzeville in Chicago illustrate the validity of the proposed blockchain-based transactive energy management for devising a distributed,scalable,efficient,and cybersecured power grid operation.The conclusion of the paper summarizes the prospects for blockchain applications to transactive energy management in power distribution systems.
文摘The locations of marine ranch and its surrounding islands are far away from the mainland,so the cost is too high to keep power supply by laying submarine cables from the mainland.Therefore,it is necessary to build a land-sea relay networked microgrids with high propor-tion of renewable energy,which is able to provide multi-energy complementary and reli-able power for marine ranch and its surrounding islands.It is noteworthy that the networked microgrids is a typical cyber-physical system.In order to deeply reveal the cyber physical fusion characteristics of fishery networked microgrids,the morphology and key techniques of fishery networked microgrids are summarized from two aspects:physical system and cyber system.And the interactions of cyber and physical system are described,including the support from cyber system for the physical system as state perception and control,and the power support from physical system for cyber system.Based on the above interactions,the related research on coupling analysis of cyber-physical system is summa-rized.Finally,some urgently studied problems have been looked forward to in fishery net-worked microgrids cyber-physical system.
文摘In this work,a PSCAD electromagnetic model is constructed for a microgrid community.It consists of three microgrids networked through the medium voltage(MV)distribution system as a practical case of the distributed resource island systems of IEEE Standard 1547.4.Typical operational scenarios are then simulated for both grid connected and islanded mode of operation.The study outcomes demonstrate the operational feasibility of networked microgrids in electrical distribution systems and the effectiveness of common droop controls in facilitating energy transaction of the microgrids and maintaining voltage and frequency stabilities under normal network disturbances.This investigation is significant in that it addresses the needs and issues arising from primary controls for facilitating the energy transactions of secondary and tertiary controls in the hierarchical control strategy of networked microgrids in the MV distribution system.Future studies of the secondary and tertiary control algorithms will need to incorporate new requirements for ensuring distribution system voltage and frequency securities.
文摘Microgrid(MG)is a small-scale,self-sufficient power system that accommodates various distributed energy resources(DERs),controllable loads,and future distribution systems.Networked microgrids(NMGs)are clusters of MGs,which are physically interconnected and functionally coordinated to enhance distribution systems in terms of economics,resilience,and reliability.This paper introduces the architecture and control of NMGs including nanogrid(NG)and MG.To accommodate variable DERs in NMGs,master and distributed control strategies are adopted to manage the high penetration of DERs,where master control focuses on economic operation,while distributed control focuses on reliability and resilience through active power sharing and voltage and frequency regulation.The initial practices of NG,MG,and NMG in the networked Illinois Institute of Technology(IIT)campus microgrid(ICM)and Bronzeville community microgrid(BCM)in the U.S.are presented.The applications of the master and distributed control strategies are illustrated for the networked ICM-BCM to show their benefits to economics,resilience,and reliability.
基金supported by the National Natural Science Foundation of China(No.5217070269).
文摘Networked microgrids(NMGs)are critical in theaccommodation of distributed renewable energy.However,theexisting centralized state estimation(SE)cannot meet the demandsof NMGs in distributed energy management.The currentestimator is also not robust against bad data.This study introducesthe concepts of relative error to construct an improvedrobust SE(IRSE)optimization model with mixed-integer nonlinearprogramming(MINLP)that overcomes the disadvantage ofinaccurate results derived from different measurements whenthe same tolerance range is considered in the robust SE(RSE).To improve the computation efficiency of the IRSE optimizationmodel,the number of binary variables is reduced based on theprojection statistics and normalized residual methods,which effectivelyavoid the problem of slow convergence or divergenceof the algorithm caused by too many integer variables.Finally,an embedded consensus alternating direction of multiplier method(ADMM)distribution algorithm based on outer approximation(OA)is proposed to solve the IRSE optimization model.This algorithm can accurately detect bad data and obtain SE resultsthat communicate only the boundary coupling informationwith neighbors.Numerical tests show that the proposed algorithmeffectively detects bad data,obtains more accurate SE results,and ensures the protection of private information in all microgrids.
文摘Renewable energy resources play an important role in the realization of the carbon neutrality.The microgrid can efficiently integrate numerous renewable energy systems into power distribution systems to realize power supply resiliency and environmental affinity.This paper reviews the current trend of microgrid and networked microgrid technologies worldwide,particularly in Japan,including the Flexible,Reliable,and Intelligent Energy Delivery System(FRIENDS)and some other examples of the networked microgrid.Some recent digitalized control functions of the microgrid and related systems are also introduced.
文摘The islands and offshore fish farming platforms in the deep sea can form a land-sea net-worked fishery microgrids to realize the complementary supply of energy.The fishery microgrid contains a high proportion of renewable energy sources such as wind,solar and waves,and mixed AC and DC loads such as feed machine,energy storage,and fishery robot.Due to the harsh operating environment,the possibility of equipment damage increases,and the requirements for system stability are higher.In this paper,firstly,the definition of transient stability of land-sea networked fishery microgrids is given.Then,the key features of the fishery microgrid is introduced,and the influence of the micro-source interface type,control strategy,current limiting mechanism and load characteristics on the transient stability is expounded.The definition of power Angle of fishery microgrid and the characterization of instability system are given.Next,the research trends of tran-sient stability are sorted out,evaluated and discussed from two aspects:approaches of transient stability analysis and methods to improve transient stability.Finally,the key issues that need to be solved urgently in the research on the transient stability of the land-sea networked fishery microgrids are summarized,and the relevant research direc-tions are prospected.
文摘As a growing number of microgrids(MGs)has been integrated into the modern power grids,the interconnection and applicable cooperation among multiple MGs motivate the development of networked MGs.Dynamic MGs,as an advanced networked MGs structure,can not only integrate multiple MGs into the distribution system but also fulfill the requested system network reconfiguration with improved flexibility.A general distributed control approach for networked MGs is reviewed.A distributed control framework for dynamic MGs operation is developed,along with an extensible architecture with considerations of large-scale distributed energy resources(DERs)integration.A scalable small-signal stability analysis is conducted per the proposed distributed control strategies and the conditions under which the system is exponentially stable are derived.At last,the effectiveness of the proposed control framework and stability analysis are verified using a 6-bus test feeder.
基金supported by VILLUM FONDEN under the VILLUM Investigator Grant 25920:Center for Research on Microgrids(CROM).corresponding author:,email:jdlc@energy.aau.dk,ORCID:https://orcid.org/0000-0002-3423-6367。
文摘Design and selection of advanced protection schemes have become essential for reliable and secure operation of networked microgrids.Various protection schemes that allow correct operation of microgrids have been proposed for individual systems in different topologies and connections.Nevertheless,protection schemes for networked microgrids are still in devel-opment,and further research is required to design and operate advanced protection in interconnected systems.Interconnection of these microgrids in different nodes with various intercon-nection technologies increases fault occurrence and complicates protection operation.This paper aims to point out challenges in developing protection for networked microgrids,potential solutions,and research areas that need to be addressed for their development.First,this article presents a systematic analysis of different microgrid clusters proposed since 2016,including several architectures of networked microgrids,operation modes,components,and utilization of renewable sources,which have not been widely explored in previous review papers.Second,the paper presents a discussion on protection systems currently available for microgrid clusters,current challenges,and solutions that have been proposed for these systems.Finally,it discusses the trend of protection schemes in networked microgrids and presents some conclusions related to implementation.IndexTerms—Adaptive eprotection,microgrid cluster,microgrid,multiple microgrid,networked microgrid,real-time simulation,smart grid.
基金This work was supported in part by the National Key Research and Development Program of China(No.2018YFA0702200)the National Natural Science Foundation of China(No.52377079)+1 种基金the Liaoning Revitalization Talents Program of China(No.XLYC2007181)the Fundamental Research Funds for the Central Universities(No.N2204010).
文摘This paper focuses on the distributed control prob-lem in a networked microgrid(NMG)with heterogeneous ener-gy storage units(HESUs)in the environment considering multi-ple types of time delays,which include the state,input,and communication delays.To address this problem,a state feed-back control(SFC)strategy based on nested predictor is pro-posed to mitigate the influence of multiple types of time delays.First,a distributed control method founded upon voltage ob-server is developed,which can realize proportional power distri-bution according to the state of charge(SOC)of the HESUs,while adjusting the average voltage of the point of common cou-pling(PCC)bus in the NMG to its rated value.Then,consider-ing that there exists steady-state error resulting from the initial value of the observer and impact of time delays,an SFC strate-gy is proposed to further improve the robustness of the NMG against time delays.Finally,the experimental results demon-strate that the proposed distributed control method is capable of fully compensating for the state,input,and communication delay.Moreover,the NMG exhibits remarkable resistance to multiple types of time delays,which has higher reliability and robustness.
文摘Microgrids are gaining popularity by facilitating distributed energy resources(DERs)and forming essential consumer/prosumer centric integrated energy systems.Integration,coordination and control of multiple DERs and managing the energy transition in this environment is a strenuous task.Classical control techniques are not enough to support dynamic microgrid environments.Implementation of Artificial Intelligence(AI)techniques seems to be a promising solution to enhance the control and operation of microgrids in future smart grid networks.Therefore,this paper briefly reviews the control architectures,existing conventional controlling techniques,their drawbacks,the need for intelligent controllers and then extensively reviews the possibility of AI implementation in different control structures with a special focus on the hierarchical control layers.This paper also investigates the AI-based control strategies in networked/interconnected/multi-microgrids environments.It concludes with the summary and future scopes of AI implementation in hierarchical control layers and structures including single and networked microgrids environments.
文摘In this paper, we elaborate a new strategy based on cooperative game theory models to encourage and manage the interactions in a MicroGrid network. The proposed strategy optimizes the cooperation and the energy exchange in a distributed μGrid network. The strategy consists of a two stage algorithm: Coalition formation algorithm which was specifically created to approximate the optimal set of coalitions that return considerable savings. And the Matching game to manage the energy exchange inside each coalition. The performance of our strategy was verified through simulations. These latter show that the losses can be considerably decreased by the use of the proposed strategy: the rate of the loss reduction can reach up to 20% if the two stages are applied on the network. Moreover, the strategy proved to have a fast convergence which makes it operational for real implemented networks.
