The wide application of intelligent terminals in microgrids has fueled the surge of data amount in recent years.In real-world scenarios,microgrids must store large amounts of data efficiently while also being able to ...The wide application of intelligent terminals in microgrids has fueled the surge of data amount in recent years.In real-world scenarios,microgrids must store large amounts of data efficiently while also being able to withstand malicious cyberattacks.To meet the high hardware resource requirements,address the vulnerability to network attacks and poor reliability in the tradi-tional centralized data storage schemes,this paper proposes a secure storage management method for microgrid data that considers node trust and directed acyclic graph(DAG)consensus mechanism.Firstly,the microgrid data storage model is designed based on the edge computing technology.The blockchain,deployed on the edge computing server and combined with cloud storage,ensures reliable data storage in the microgrid.Secondly,a blockchain consen-sus algorithm based on directed acyclic graph data structure is then proposed to effectively improve the data storage timeliness and avoid disadvantages in traditional blockchain topology such as long chain construction time and low consensus efficiency.Finally,considering the tolerance differences among the candidate chain-building nodes to network attacks,a hash value update mechanism of blockchain header with node trust identification to ensure data storage security is proposed.Experimental results from the microgrid data storage platform show that the proposed method can achieve a private key update time of less than 5 milliseconds.When the number of blockchain nodes is less than 25,the blockchain construction takes no more than 80 mins,and the data throughput is close to 300 kbps.Compared with the traditional chain-topology-based consensus methods that do not consider node trust,the proposed method has higher efficiency in data storage and better resistance to network attacks.展开更多
This paper proposes a control strategy that can realize seamless microgrid operation mode transition between grid-connected operation and stand-alone operation.The scenario of a microgrid based on master-slave control...This paper proposes a control strategy that can realize seamless microgrid operation mode transition between grid-connected operation and stand-alone operation.The scenario of a microgrid based on master-slave control is considered,where the master distributed generation(DG) unit operates in different control schemes in different microgrid operation modes,while other slave DG units operate with power/current control all the time.The proposed control strategy focuses on the master DG unit,and contains the control state/reference compensation algorithm and separation switch control logic.The proposed method can effectively reduce the impact on the critical loads and DG units caused by microgrid operation mode transitions.展开更多
文摘The wide application of intelligent terminals in microgrids has fueled the surge of data amount in recent years.In real-world scenarios,microgrids must store large amounts of data efficiently while also being able to withstand malicious cyberattacks.To meet the high hardware resource requirements,address the vulnerability to network attacks and poor reliability in the tradi-tional centralized data storage schemes,this paper proposes a secure storage management method for microgrid data that considers node trust and directed acyclic graph(DAG)consensus mechanism.Firstly,the microgrid data storage model is designed based on the edge computing technology.The blockchain,deployed on the edge computing server and combined with cloud storage,ensures reliable data storage in the microgrid.Secondly,a blockchain consen-sus algorithm based on directed acyclic graph data structure is then proposed to effectively improve the data storage timeliness and avoid disadvantages in traditional blockchain topology such as long chain construction time and low consensus efficiency.Finally,considering the tolerance differences among the candidate chain-building nodes to network attacks,a hash value update mechanism of blockchain header with node trust identification to ensure data storage security is proposed.Experimental results from the microgrid data storage platform show that the proposed method can achieve a private key update time of less than 5 milliseconds.When the number of blockchain nodes is less than 25,the blockchain construction takes no more than 80 mins,and the data throughput is close to 300 kbps.Compared with the traditional chain-topology-based consensus methods that do not consider node trust,the proposed method has higher efficiency in data storage and better resistance to network attacks.
基金supported by the National Basic Research Program of China ("973" Project) (Grant No. 2009CB219700)the National Natural Science Foundation of China (Grant No. 50837001)
文摘This paper proposes a control strategy that can realize seamless microgrid operation mode transition between grid-connected operation and stand-alone operation.The scenario of a microgrid based on master-slave control is considered,where the master distributed generation(DG) unit operates in different control schemes in different microgrid operation modes,while other slave DG units operate with power/current control all the time.The proposed control strategy focuses on the master DG unit,and contains the control state/reference compensation algorithm and separation switch control logic.The proposed method can effectively reduce the impact on the critical loads and DG units caused by microgrid operation mode transitions.
