In this paper,a robust method for quantifying the impact of short-circuit faults on microgrids is proposed.Microgrids can operate in both islanded(grid-forming)and gridconnected(grid-following)modes,and the ownership ...In this paper,a robust method for quantifying the impact of short-circuit faults on microgrids is proposed.Microgrids can operate in both islanded(grid-forming)and gridconnected(grid-following)modes,and the ownership and responsibility for the microgrid operation can vary significantly from distribution system operators(DSOs)to third-party microgrid operators.This necessitates the development of a robust short-circuit calculation(SCC)method that can provide accurate results for all the possible microgrid topologies,operational modes,and ownership models.Unlike previously developed SCC methods for microgrids,the SCC method proposed in this paper provides highly accurate results for all possible microgrid topologies:islanded microgrid,grid-connected microgrid,and utility microgrid as a part of a larger distribution grid.In addition,the proposed SCC method solves the short-circuit faults of any complexity,with the same simplicity.The proposed SCC method is tested on a complete model of a real-life microgrid on the Case Western Reserve University campus,operating in both islanded and grid-connected modes.The computational results show the advantages of the proposed SCC method in comparison to the previous ones for microgrids,regarding the robustness(ability to solve complex short-circuit faults with an arbitrary number of faulted buses and phases that affect a microgrid of any topology),as well as the accuracy of the results.展开更多
We aim to systematically review challenges imposed by emerging distributed energy resources(DERs)to model in two basic distribution management system(DMS)online applications—power flow and short-circuit analysis,as w...We aim to systematically review challenges imposed by emerging distributed energy resources(DERs)to model in two basic distribution management system(DMS)online applications—power flow and short-circuit analysis,as well as to offer a systematic review of potential solutions.In the last decade,electronically coupled DERs became increasingly popular.DERs can employ a wide range of control strategies for power,current,or voltage control,in both normal and faulted conditions.Therefore,DERs cannot be modeled with the traditional PQ(load or generator bus)or PV(generator bus)bus types used for modeling synchronous and induction machines in online power flow calculations.Moreover,since fault currents of DERs are limited to predefined maximal values,electronically coupled DERs cannot be represented with traditional voltage source behind impedance models for online short-circuit calculation(SCC).However,most of the DMS software packages still use the traditional models to represent all DER types,including those that are electronically coupled.This paper shows that there will be large calculation errors in such practice,which make the system model an inadequate representation of the system.This will lead to serious errors in the management,control,and operation of distribution systems.Nonetheless,potential solutions to the challenges are systematically reviewed.Finally,the calculation results on a distribution test system with all DER types are used to prove the claim.展开更多
文摘In this paper,a robust method for quantifying the impact of short-circuit faults on microgrids is proposed.Microgrids can operate in both islanded(grid-forming)and gridconnected(grid-following)modes,and the ownership and responsibility for the microgrid operation can vary significantly from distribution system operators(DSOs)to third-party microgrid operators.This necessitates the development of a robust short-circuit calculation(SCC)method that can provide accurate results for all the possible microgrid topologies,operational modes,and ownership models.Unlike previously developed SCC methods for microgrids,the SCC method proposed in this paper provides highly accurate results for all possible microgrid topologies:islanded microgrid,grid-connected microgrid,and utility microgrid as a part of a larger distribution grid.In addition,the proposed SCC method solves the short-circuit faults of any complexity,with the same simplicity.The proposed SCC method is tested on a complete model of a real-life microgrid on the Case Western Reserve University campus,operating in both islanded and grid-connected modes.The computational results show the advantages of the proposed SCC method in comparison to the previous ones for microgrids,regarding the robustness(ability to solve complex short-circuit faults with an arbitrary number of faulted buses and phases that affect a microgrid of any topology),as well as the accuracy of the results.
基金the Ministry of Education and Science of the Republic of Serbia for its support to this research through the ProjectⅢ-42004.
文摘We aim to systematically review challenges imposed by emerging distributed energy resources(DERs)to model in two basic distribution management system(DMS)online applications—power flow and short-circuit analysis,as well as to offer a systematic review of potential solutions.In the last decade,electronically coupled DERs became increasingly popular.DERs can employ a wide range of control strategies for power,current,or voltage control,in both normal and faulted conditions.Therefore,DERs cannot be modeled with the traditional PQ(load or generator bus)or PV(generator bus)bus types used for modeling synchronous and induction machines in online power flow calculations.Moreover,since fault currents of DERs are limited to predefined maximal values,electronically coupled DERs cannot be represented with traditional voltage source behind impedance models for online short-circuit calculation(SCC).However,most of the DMS software packages still use the traditional models to represent all DER types,including those that are electronically coupled.This paper shows that there will be large calculation errors in such practice,which make the system model an inadequate representation of the system.This will lead to serious errors in the management,control,and operation of distribution systems.Nonetheless,potential solutions to the challenges are systematically reviewed.Finally,the calculation results on a distribution test system with all DER types are used to prove the claim.
