排序方式: 共有60条查询结果,搜索用时 31 毫秒
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Due to rapid advancements in power electronics, the utilization of electronically switched loads and nonlinear loads is increasing gradually in the electrical power system. These loads create problems of measuring instruments, when connected to the power distribution systems. In this paper, an experimental investigation has been carried out to analyze the performance of single-phase watt-hour (induction and electronic types) energy meters that are being used in Pakistan. The accuracy of the energy meters has been tested under different household nonlinear loads, at various power factors and also at different supply voltage levels. Power factor and total harmonic distortion (THD) of different household loads are also recorded in the experimental work. A hardware based experimental setup has been designed to perform the experimental work. The experimental results have been compared to Water and Power Development Authority (WAPDA) standards for energy meters. 相似文献
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黄文 《电力机车与城轨车辆》2011,34(2):59-62
重载列车操纵技术是提高重载列车运行可靠性的技术手段之一,是一项十分重要的研究课题.文章针对大秦线重载列车的技术特点,以HXD型机车为例,从理论方面分析列车操纵难点,提出了重载列车平稳操纵的基本原则和方法. 相似文献
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一、驾驶员维修保障存在的问题
(一)自我保障有困难,依赖思想还存在.调研发现,有部分驾驶员认为车辆维修和故障排除是修理工的事,驾驶员的职责就是"开好车、不出事".由于车辆大部分时间处于封存状态,车辆故障不易发现,加之部分驾驶员维修技能较弱,当车辆出现故障后,只能等待修理工处理.
(二)训练保障跟不上,维修训练不经常.调研发现,驾驶员的维修训练时机多为驾驶员复训、补训阶段,其余时间驾驶员配属到被保障单位搞协同训练.复训、补训重点在于提高驾驶员技能,而维修训练则存在"一般课目反复训、重点课目简化训、难点课目绕开训"现象,驾驶员维修技能提升缓慢. 相似文献
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为解决深中通道特长海底沉管隧道在火灾情况下人、车疏散救援难题,运用Pathfinder和Vissim数值仿真进行沉管隧道内人员逃生和车辆疏散研究,并提出沉管隧道火灾应急救援及交通控制策略。结果表明,沉管隧道匝道路段在烟囱效应影响下人员疏散可用时间较短,需要有效的通风排烟策略及应急救援策略;尽管东、西人工岛及三围互通救援站可满足救援相关时间要求,但火灾情况下人员疏散应采用弃车逃生的方式。基于应急资源配置及应急救援体系提出的应急救援及交通控制策略,能够满足沉管隧道内突发事故下应急救援需求。 相似文献
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