24小时热门版块排行榜    

查看: 449  |  回复: 2
本帖产生 1 个 翻译EPI ,点击这里进行查看

kangfulike

无虫 (职业作家)

[求助] 翻译摘要!

Detecting and locating insulation defects in wiring systems
is a non-trivial challenge. Ideally, the diagnostic should be
non-destructive, capable of detecting a variety of insulation defects
(such as cracking, chafing, and abrasion), and should be
able to locate the defect accurately to reduce potential inspection
and maintenance costs. The diagnostic should also have a low
rate of false detection. Complicating this quest is the nature of
some complex wiring systems. For example, commercial aircraft
wiring systems are composed of harnesses containing single
wire pairs that are periodically bound by ties or lacing, which
creates highly non-uniform impedance profiles down the line
length. Insulation defects may be physically small, resulting in
an immeasurable change in the impedance at the defect site. These
characteristics tend to render impedance measuring or conventional
time-domain-reflectometry (TDR) concepts ineffective.
Other approaches, such as partial discharge or DC breakdown
techniques, may detect some types of insulation defects but cannot
locate them in complex impedance wiring systems.
Pulse Arrested Spark Discharge (PASD) has been demonstrated
for many types of faults, types of constructions, and insulations
to be an effective insulation diagnostic. These include coaxial
cables, twisted shielded pair, and more complex single-wire
bundles commonly found in aircraft wiring systems. PASD employs
a patented low-energy, arrested-arc concept and TDR techniques
to produce a well-defined reflection from an insulation
defect site. The PASD diagnostic has detected and located a range
of electrical insulation damage in cable/wire bundles with nonuniform
impedance profiles. It was first demonstrated on electrical
wiring systems in 1996 under a Department of EnergysponsoredNuclear Energy (DOE) program. Success during initial
development of PASD for the DOE led to a contract with the
US Navy to explore the use of this concept for complex wiring in
control and power systems. This work, completed in August 2001,
demonstrated the ability of this technique to identify and locate
gross defects and difficult small-volume dielectric defects in a
laboratory environment [1]. This foundational work with PASD
led to a 3-yr US Federal Aviation Administration (FAA) program,
beginning in October 2002, with a focus on commercial aircraft
wiring systems and a reduction to practice of the PASD technique.
PASD has demonstrated the potential to locate difficult
aircraft wiring flaws relevant to aging processes, manufacturing
defects, and installation damage as well as a variety of other defects in more conventional wire/cable systems [2]. Sandia National
Laboratories was awarded a US Patent for PASD on February
8, 2005

» 猜你喜欢

已阅   回复此楼   关注TA 给TA发消息 送TA红花 TA的回帖

sally88814

荣誉版主 (文坛精英)

优秀版主

【答案】应助回帖

在线路系统中探测与定位某些孤立的缺陷是一项很具有挑战性的工作。在理想的状态下,诊断应该是对线路是无损的,而且能够顺利的检测出能各种孤立的缺陷(如开裂、磨损、腐蚀),还应该能够准确地检测出缺陷的位置来减少潜在的检测与维修费用。诊断也应该有一个低错误的检测率。一些复杂的线路系统上的这项工作更加繁重。例如商用飞机的线路系统是由线束组成的,这些线束又是由用 结或者结带周期性地捆绑在一起的单双绞线组成的,这样能够在沿着线长的方向上产生不均一的阻抗剖面。孤立缺陷也许是很小的,但是缺能够在缺陷位置处的阻抗产生不可测量的改变。这些性质就使得测量阻抗的方法或者常规的时间主导反射计概念无效。其他的方法,比如局部放电或者直流故障技术,也许能够检测出一些类型的孤立缺陷,但是不能够在复杂的阻抗线路系统中去定位他们。脉冲捕捉火花放电技术在很多的故障系统,组建系统与孤立系统中已经被证实是一种有效的诊断技术。这些系统包括同轴电缆,缠绕的屏蔽线对与一些在飞机上发现的单线束。PASD利用低能,捕捉电弧的概念与TDR技术给出了一个来自于缺陷位置的明确的倒影。PASD技术已经探测出与定位了一系列的在非均一阻抗剖面的电缆线束这个是在1996年有一个能源赞助核能项目部在电路系统中第一次被证实的。DOE成功地发展起来的PASD技术被用于美国的海军部队,他们在控制和电力业复杂的线路系统中探索这个技术的运用。
2楼2012-02-15 14:09:41
已阅   回复此楼   关注TA 给TA发消息 送TA红花 TA的回帖

sally88814

荣誉版主 (文坛精英)

优秀版主

【答案】应助回帖

kangfulike(金币+20, 翻译EPI+1): ★★★★★最佳答案 谢谢!真的非常感谢! 2012-02-15 15:04:23
这项工作完成于2011年八月,在实验室的条件下证明了这个技术能够确定与定位重大缺陷与一些疑难的小型介电缺陷。与PASD有关的基础工作启动了3个美国联邦航空署项目,项目起始于2002年10月,重点集中在商用飞机布线系统与缩小PASD技术的实践范围。PASD技术在定位与老化过程,制造缺陷与孤立缺陷以及在更多的常规线路/电缆线路系统有关联的飞机线路故障方面被证明有巨大的潜力。Sandia 国家实验室在2005年2月8给PASD技术颁发了美国专利。
3楼2012-02-15 14:26:01
已阅   回复此楼   关注TA 给TA发消息 送TA红花 TA的回帖
相关版块跳转 我要订阅楼主 kangfulike 的主题更新
信息提示
请填处理意见