Research on high-speed railways is a relatively new yet highly significant field in Vietnam.Among its key components,train control signaling plays a critical role,as it directly affects various interconnected systems,...Research on high-speed railways is a relatively new yet highly significant field in Vietnam.Among its key components,train control signaling plays a critical role,as it directly affects various interconnected systems,including infrastructure,traction power supply,operational planning,and overall railway safety.This article focuses on evaluating the capacity of the line based on the types of signals suitable for high-speed railways that have been effectively implemented in several European countries and successfully adapted in China.The research and simulation are conducted using MATLAB software,a reliable and widely adopted tool in the scientific community.The findings demonstrate that under normal conditions,the European Railway Traffic Management System/European Train Control System(ERTMS/ETCS)Level 2 signaling can support up to 23.7485 trains/hour/direction.Meanwhile,ERTMS/ETCS Level 3 with full moving block can accommodate up to 30.8735 trains/hour/direction,and ERTMS/ETCS Level 3 with fixed virtual blocks up to 29.4694 trains/hour/direction.In emergency scenarios,ERTMS/ETCS Level 3 with full moving block reduces headway by 33.27%compared to CTCS Level 3,while ERTMS/ETCS Level 3 with fixed virtual blocks achieves a 28.78%reduction.Overall,the ERTMS/ETCS Level 3 emerges as a state-of-the-art signaling technology offering high capacity and operational efficiency,and is recommended as a forward-looking solution for future implementation in Vietnam.展开更多
Themassive integration of high-proportioned distributed photovoltaics into distribution networks poses significant challenges to the flexible regulation capabilities of distribution stations.To accurately assess the f...Themassive integration of high-proportioned distributed photovoltaics into distribution networks poses significant challenges to the flexible regulation capabilities of distribution stations.To accurately assess the flexible regulation capabilities of distribution stations,amulti-temporal and spatial scale regulation capability assessment technique is proposed for distribution station areas with distributed photovoltaics,considering different geographical locations,coverage areas,and response capabilities.Firstly,the multi-temporal scale regulation characteristics and response capabilities of different regulation resources in distribution station areas are analyzed,and a resource regulation capability model is established to quantify the adjustable range of different regulation resources.On this basis,considering the limitations of line transmission capacity,a regulation capability assessment index for distribution stations is proposed to evaluate their regulation capabilities.Secondly,considering different geographical locations and coverage areas,a comprehensive performance index based on electrical distance modularity and active power balance is established,and a cluster division method based on genetic algorithms is proposed to fully leverage the coordination and complementarity among nodes and improve the active power matching degree within clusters.Simultaneously,an economic optimization model with the objective of minimizing the economic cost of the distribution station is established,comprehensively considering the safety constraints of the distribution network and the regulation constraints of resources.This model can provide scientific guidance for the economic dispatch of the distribution station area.Finally,case studies demonstrate that the proposed assessment and optimization methods effectively evaluate the regulation capabilities of distribution stations,facilitate the consumption of distributed photovoltaics,and enhance the economic efficiency of the distribution station area.展开更多
Home power outlets can be connected in various topologies： derivation, star, cascade. This paper firstly describes the intrinsic behavior of the transfer function of these basic topologies. Secondly, the channel capa...Home power outlets can be connected in various topologies： derivation, star, cascade. This paper firstly describes the intrinsic behavior of the transfer function of these basic topologies. Secondly, the channel capacities of the three topologies are compared to check if there is a more favorable topology. Many deterministic modeling methods have been developed to compute the transfer function of power line networks but the given examples in the studies correspond only to the derivation topology with branches connected to the direct path between transceivers. Thirdly, this paper evaluates the ability of common modeling methods （multipath and chain matrices） to compute accurately the transfer function of any topology. Modeling the derivation topology with ＂secondary＂ branches and the star topology is shown to be inappropriate with chain matrices based method. Indeed, this method is very sensitive to the uncertainty of the second parameters of the power cables and this induces considerable fading shifts for those topologies. Multipath modeling method produces results agreeing with measurements for any topology.展开更多
文摘Research on high-speed railways is a relatively new yet highly significant field in Vietnam.Among its key components,train control signaling plays a critical role,as it directly affects various interconnected systems,including infrastructure,traction power supply,operational planning,and overall railway safety.This article focuses on evaluating the capacity of the line based on the types of signals suitable for high-speed railways that have been effectively implemented in several European countries and successfully adapted in China.The research and simulation are conducted using MATLAB software,a reliable and widely adopted tool in the scientific community.The findings demonstrate that under normal conditions,the European Railway Traffic Management System/European Train Control System(ERTMS/ETCS)Level 2 signaling can support up to 23.7485 trains/hour/direction.Meanwhile,ERTMS/ETCS Level 3 with full moving block can accommodate up to 30.8735 trains/hour/direction,and ERTMS/ETCS Level 3 with fixed virtual blocks up to 29.4694 trains/hour/direction.In emergency scenarios,ERTMS/ETCS Level 3 with full moving block reduces headway by 33.27%compared to CTCS Level 3,while ERTMS/ETCS Level 3 with fixed virtual blocks achieves a 28.78%reduction.Overall,the ERTMS/ETCS Level 3 emerges as a state-of-the-art signaling technology offering high capacity and operational efficiency,and is recommended as a forward-looking solution for future implementation in Vietnam.
基金funded by the“Research and Application Project of Collaborative Optimization Control Technology for Distribution Station Area for High Proportion Distributed PV Consumption(4000-202318079A-1-1-ZN)”of the Headquarters of the State Grid Corporation.
文摘Themassive integration of high-proportioned distributed photovoltaics into distribution networks poses significant challenges to the flexible regulation capabilities of distribution stations.To accurately assess the flexible regulation capabilities of distribution stations,amulti-temporal and spatial scale regulation capability assessment technique is proposed for distribution station areas with distributed photovoltaics,considering different geographical locations,coverage areas,and response capabilities.Firstly,the multi-temporal scale regulation characteristics and response capabilities of different regulation resources in distribution station areas are analyzed,and a resource regulation capability model is established to quantify the adjustable range of different regulation resources.On this basis,considering the limitations of line transmission capacity,a regulation capability assessment index for distribution stations is proposed to evaluate their regulation capabilities.Secondly,considering different geographical locations and coverage areas,a comprehensive performance index based on electrical distance modularity and active power balance is established,and a cluster division method based on genetic algorithms is proposed to fully leverage the coordination and complementarity among nodes and improve the active power matching degree within clusters.Simultaneously,an economic optimization model with the objective of minimizing the economic cost of the distribution station is established,comprehensively considering the safety constraints of the distribution network and the regulation constraints of resources.This model can provide scientific guidance for the economic dispatch of the distribution station area.Finally,case studies demonstrate that the proposed assessment and optimization methods effectively evaluate the regulation capabilities of distribution stations,facilitate the consumption of distributed photovoltaics,and enhance the economic efficiency of the distribution station area.
文摘Home power outlets can be connected in various topologies： derivation, star, cascade. This paper firstly describes the intrinsic behavior of the transfer function of these basic topologies. Secondly, the channel capacities of the three topologies are compared to check if there is a more favorable topology. Many deterministic modeling methods have been developed to compute the transfer function of power line networks but the given examples in the studies correspond only to the derivation topology with branches connected to the direct path between transceivers. Thirdly, this paper evaluates the ability of common modeling methods （multipath and chain matrices） to compute accurately the transfer function of any topology. Modeling the derivation topology with ＂secondary＂ branches and the star topology is shown to be inappropriate with chain matrices based method. Indeed, this method is very sensitive to the uncertainty of the second parameters of the power cables and this induces considerable fading shifts for those topologies. Multipath modeling method produces results agreeing with measurements for any topology.
