浅谈地铁供电设备差动保护跳闸技术

随着地铁建设的不断扩大,人们越来越重视地铁运营的安全性和稳定性。供电安全是地铁运营安全的关键,相关人员应积极研究地铁供电设备的安全防护技术,在地铁供电设备运行过程中,需要使用差动保护跳闸技术,该文主要分析了城市地铁供电设备在运行过程中需要使用差动保护跳闸技术的重要原因以及地铁供电设备的日常预防性维修措施。     

地铁直流供电保护相关问题探讨

地铁直流牵引供电系统是一个复杂的系统,其中最为重要技术是直流供电控制与保护技术,直流供电保护系统对于地铁的安全运行起着决定性的作用,因而研究地铁直流供电系统,不断优化和创新,对提高地铁安全性有着重要的意义,本文就地铁直流供电保护相关问题展开探讨,探讨了开关柜的结构,并对其保护方法及相应原理进行了分析,以期为地铁直流供电保护的研究和发展作出应有的贡献。     

1500伏断路器联跳闭锁重合闸启动探索

本文对广州地铁二号线西门子DC1500V断路器联跳保护跳闸后,被联跳断路器闭锁重合闸启动原因进行分析和探讨,得出相应结论并提出改进措施。     

基于供电线路的距离保护问题研究

供电线路距离保护指的是依据短路故障处点处与保护装置之间的距离远近,以确定动作的采取时间从而及时的采取相应保护措施的一种装置。本文从供电线路距离保护的相关背景出发,分析了在供电线路中采取距离保护措施的重要性,并研究了距离保护在供电线路中的具体应用。     

深圳市地铁龙岗线3207标EPB控制系统浅析

地铁机车采用直流牵引,对牵引供电系统稳定性和可靠性有很高的要求,所以地铁直流牵引供电系统的保护是地铁供电系统稳定可靠工作的关键所在。结合深圳市轨道交通二期龙岗线工程供电系统设置的正线EPB控制系统,介绍了EPB系统在有牵引所和无牵引所两种情况下的车站中的工作原理,重点分析双边供电模式下EPB系统的控制过程。     

杭州地铁车辆辅助系统的两种中压供电方式比较

简述地铁车辆的辅助系统功能,以杭州地铁1号线和2号线为例分析辅助系统两种中压供电方式的特点及故障情况下的处理方案和影响,并对其优缺点进行比较。     

论地铁供电系统的可靠性研究

随着地铁的大范围使用，其安全性逐渐成为人们所关注的焦点，而保证地铁安全稳定运行的关键则是地铁供电系统的平稳运行。如果供电系统出现问题，不仅会给社会带来较大的经济损失，而且还会危及乘客的生命安全，更严重的将会引起整个城市交通的瘫痪。本论文从地铁供电系统可靠性研究的社会背景和意义、供电系统的结构分析、影响供电系统可靠性的因素及改进方法这四方面给以论述，强调了地铁供电系统可靠性研究的必要性。     

地铁开式通风系统喷嘴送风研究

地铁开式通风系统事故时风机联动范围大,时滞长,可靠性和及时性较差,主要针对地铁开式通风系统喷嘴送风进行研究。采用Fluent数值模拟方法,从送风角度、布置位置对顶置和侧置喷嘴进行了优化,获得了顶置和侧置喷嘴最佳布置形式。对两种喷嘴形式下隧道风机进行了选型计算。最后采用SES对区间隧道火灾喷嘴送风风机动作模式进行模拟,结果表明,通过喷嘴送风,可减小风机动作数量,通过动作事故区间相邻车站的隧道风机即可满足区间风速要求,系统可靠性和及时性大大提高。     

单端供电网络保护简析

在一些供电网络中，为了减少投资，常常采用单端供电的形式，这就要求供电线路必须要有合理的继电保护装置，以保证单端供电网络的可靠运行。本文正是基于此情况，对单端供电网络的保护进行分析，阐述合理的保护方式。     

浅析地铁出入段线行车管理与供电接口

根据西安地铁二号线车辆段线与出入段线的设置情况,结合在运营生产中出现的问题进行分析,供电分区与行车管理的交叉影响地铁施工的效率并增加了行车管理的难度,从信号、供电设备与行车管理的接口关系进行研究,提出相应的解决方法。     

Wear and T.E.M. Studies of P.E.C.V.D. Diamond-like-Carbon Films

Diamond-like-carbon (D.L.C.) films are characterized by a low friction coefficient, a high wear resistance and a high corrosion resistance. D.L.C. films can be obtained by P.V.D., C.V.D. and duplex techniques with solid or gaseous precursors. Depending on the processing, hydrogen concentration ranges between 0 and 60%

In this study, hydrogenated D.L.C. has been deposited with a radio frequency system (13.56 MHz) onto a steel substrate. Wear was studied by pin-on-disc testing at room temperature with an alumina counterpart. Interrupted tests were carried out to go into wear mechanisms. Debris were collected after various given sliding times for transmission electron microscopy (T.E.M.) in addition to scanning electron microscopy (S.E.M.) applied to the wear tracks.     

MAS n.m.r. and e.s.r. studies of MnAlPO5

²⁷Al and ³¹P magic angle spinning (MAS) n.m.r. and e.s.r. measurements have been performed on MnAlPO5 in order to obtain direct evidence for Mn⁺² incorporation into tetrahedral sites in the framework. Two samples differing in their Mn content have been studied, and their results were compared with those obtained from impregnated Mn-AlPO5 and exchanged Mn-SAPO5 where the Mn⁺² does not occupy framework sites. The MAS n.m.r. spectrum showed a large anisotropy, manifested in numerous side bands due to the paramagnetic shifts induced by dipolar interactions between the unpaired electrons of the Mn⁺² and the ³¹P and ²⁷Al nuclei in its vicinity. On dehydration, a considerable linewidth narrowing has been observed, attributed to a decrease in the electronic relaxation time induced by increase in Mn⁺² spin-exchange interaction. Calculated³¹P MAS n.m.r spectra, where the paramagnetic shift anisotropy was obtained from X-ray diffraction data of AlPO5 and taking into account the Mn content obtained from the chemical analysis, showed qualitative agreement with the experimental spectra. Comparison of the simulated and experimental spectra indicates that, indeed, part of the Mn⁺² cations occupy framework sites; it does, however, also suggest that extraframework Mn⁺² cations are present as well. These conclusions are further supported by e.s.r. measurements. The e.s.r. spectrum of MnAlPO5 shows resolved hyperfine lines with splitting characteristics of octahedral Mn⁺², supporting the existence of extraframework Mn⁺². On dehydration, the spectrum of MnAlPO5 coalesce into a single absorption line. This coalescence is attributed to increase in the spin-exchange interaction due to migration of probably extraframework Mn⁺² toward the framework.     

Prof. Dipl.-Ing. Dr. techn. Dr. h. c. Wilhelm Schneider

Summary In order to provide a firmer foundation on which some reciprocity theorems in Eshelbian mechanics where established earlier, a nonlinear and then linearized formulation of these theorems is presented. To carry out the required operations a simple two-degrees-of-freedom system was chosen. The analysis led to mostly algebraic expressions which are also illustrated graphically. Readers will be very sad to learn of the mournful death on January 7, 2007, of Prof. Dr. sc. techn. Dr. h. c. George Herrmann. Dedicated to Professor Franz Ziegler on the occasion of his 70th birthday