在电气化铁路牵引供电系统中,铁路能量路由器(railway energy router,RER)用于回收列车制动能量、接入光伏等新能源,同时改善负序、无功等电能质量,但是既有结构包含两套逆变器和变压器,存在成本高、工程应用难的问题。为此,提出一种基...在电气化铁路牵引供电系统中,铁路能量路由器(railway energy router,RER)用于回收列车制动能量、接入光伏等新能源,同时改善负序、无功等电能质量,但是既有结构包含两套逆变器和变压器,存在成本高、工程应用难的问题。为此,提出一种基于跨相式单相逆变器的新型铁路能量路由器结构,其交流侧跨接α/β相牵引母线、直流侧接入光伏储能。首先,推导新型结构的数学模型和工作原理;然后,针对逆变器传统两端口模式转变为RER的三端口模式存在的有功/无功耦合问题,提出增加无功补偿装置的硬件解耦方法;其次,针对新型RER三端口间多向能流问题,提出一种多层协调优化控制策略。最后,基于典型工况及实测数据,进行了仿真验证,结果表明:三相电压不平衡度从2.52%降低至1.58%,平均功率因数从0.688上升至0.966,再生制动回收率61.65%,光伏消纳率94.16%;主设备容量降低42.31%,成本降低37.23%,说明所提新型RER在实现现有RER相同功能的前提下大幅降低了成本,具有重要的理论和工程价值。展开更多
The existing active queue management （AQM） algorithm acts on subscribers and edge routers only, it does not support differentiate-serve （Diffserv） quality of service （QoS）, while the existing diffserv QoS has no...The existing active queue management （AQM） algorithm acts on subscribers and edge routers only, it does not support differentiate-serve （Diffserv） quality of service （QoS）, while the existing diffserv QoS has not considered the link capacities between edge routers and connected core routers. When a core router in a two layers’ network experiences congestion, the connected edge routers have no ability to adjust their access data rates. Thus, it is difficult to achieve the congestion control for the large scale network with many edge routers and core routers. To solve these problems, two difffserve AQM algorithms are proposed for the congestion control of multilayer network. One diffserv AQM algorithm implements fair link capacities of edge routers, and the other one implements unequal link capacities of edge routers, but it requires the core routers to have multi-queues buffers and Diffserv AQM to support. The proposed algorithms achieve the network congestion control by operating AQM parameters on the conditions of proposed three theorems for core and edge routers. The dynamic simulation results demonstrate the proposed control algorithms for core and edge routers to be valid.展开更多
文摘在电气化铁路牵引供电系统中,铁路能量路由器(railway energy router,RER)用于回收列车制动能量、接入光伏等新能源,同时改善负序、无功等电能质量,但是既有结构包含两套逆变器和变压器,存在成本高、工程应用难的问题。为此,提出一种基于跨相式单相逆变器的新型铁路能量路由器结构,其交流侧跨接α/β相牵引母线、直流侧接入光伏储能。首先,推导新型结构的数学模型和工作原理;然后,针对逆变器传统两端口模式转变为RER的三端口模式存在的有功/无功耦合问题,提出增加无功补偿装置的硬件解耦方法;其次,针对新型RER三端口间多向能流问题,提出一种多层协调优化控制策略。最后,基于典型工况及实测数据,进行了仿真验证,结果表明:三相电压不平衡度从2.52%降低至1.58%,平均功率因数从0.688上升至0.966,再生制动回收率61.65%,光伏消纳率94.16%;主设备容量降低42.31%,成本降低37.23%,说明所提新型RER在实现现有RER相同功能的前提下大幅降低了成本,具有重要的理论和工程价值。
基金supported by the Beijing Natural Science Foundation (4102050)NSFC-KOSEF Joint Research Project of China and Korea(60811140343), and the CDSN, GIST.
文摘The existing active queue management （AQM） algorithm acts on subscribers and edge routers only, it does not support differentiate-serve （Diffserv） quality of service （QoS）, while the existing diffserv QoS has not considered the link capacities between edge routers and connected core routers. When a core router in a two layers’ network experiences congestion, the connected edge routers have no ability to adjust their access data rates. Thus, it is difficult to achieve the congestion control for the large scale network with many edge routers and core routers. To solve these problems, two difffserve AQM algorithms are proposed for the congestion control of multilayer network. One diffserv AQM algorithm implements fair link capacities of edge routers, and the other one implements unequal link capacities of edge routers, but it requires the core routers to have multi-queues buffers and Diffserv AQM to support. The proposed algorithms achieve the network congestion control by operating AQM parameters on the conditions of proposed three theorems for core and edge routers. The dynamic simulation results demonstrate the proposed control algorithms for core and edge routers to be valid.
