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21.
电气绝缘耐热性多年来一直是国内外重点研究项目之一,本文通过介绍其现阶段的研究发展现状和选用的基本原则,旨在提高相关从业人员对电气绝缘材料耐热性的认识。 相似文献
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现代化智能建筑中通常有多个信息监控和通信设施,因此在铺设线路之前要在布线方式和路由选择的排列进行详细设计,不但应该符合规范的要求,还要考虑布线的安全性、可扩性、经济性和美观,便于维修,电缆桥架作为承载各种电缆敷设的载体,从属于布线的需要,同样应遵循上述原则加以实施。本文就电缆桥架在设计中的技术问题进行分析和探讨。 相似文献
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本文首先分析了我国电力发展的现状及影响电力经营的相关政策;然后根据社会经济的发展,对电力的需求进行了深入剖析;最后,对公司经营的主要优势和劣势,面临的主要机遇和挑战,进行了分析总结,为公司未来发展提出了战略建议。 相似文献
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新能源汽车是未来汽车产业转型发展的重要方向。我国新能源汽车前期发展取得了突出的成绩,产销量位居世界首位。但目前产业发展正面临新形势,未来一段时期内将由“政策驱动”转向“政策+市场双驱动”。到2021年购置补贴完全退出后的后补贴时代,如何保障新能源汽车产业的健康、可持续发展,值得人们共同思考,开发什么类型的产品才能更好地满足消费者的需求,值得行业企业考虑。 相似文献
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交流接触器常见故障原因分析及处理 总被引:1,自引:0,他引:1
交流接触器是电力拖动和自动控制系统中应用最普遍的一种电器。它作为执行元件,可以远距离频繁地自动控制电动机的启动、运转和停止,以及电力线路的接通与分断。本文对交流接触器常见故障产生的原因及采取的相应处理方法进行了阐述。 相似文献
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ABSTRACTSignificant interest exists in the potential for electric vehicles (EVs) to be a source of greenhouse gas (GHG) abatement. In order to establish the extent to which EVs will deliver abatement, however, a realistic understanding of the electricity and transport sector GHG emissions impacts arising from different approaches to integrating EVs into the power system is required. A key issue in this regard is the extent to which GHG emissions are a function of where and when EV charging will be enabled (or disabled) by the provision of recharging infrastructure and implementation of charging management strategies by the electricity industry. This article presents an investigation of the GHG emissions arising from electricity and gasoline consumption by plug-in hybrid EVs under a range of standard EV-power system integration scenarios. An assessment framework is presented, and GHG emissions from EV use are assessed for the New South Wales (NSW) and South Australian (SA) pools of the Australian National Electricity Market (NEM) using retrospective electricity system generation data for 2011. Results highlight that there is a range of possible outcomes depending on the integration scenario and emissions accounting approach used. This range illustrates value of a temporally explicit assessment approach in capturing the temporal alignment of electricity sector emission intensity and EV charging. Results also show the importance of a clean electricity generation mix in order for EVs to provide a GHG abatement benefit beyond what would be achieved by a hybrid (but non-plug-in) vehicle. The extent to which overnight charging in NSW is observed to produce higher emissions relative to unmanaged charging also illustrates a possible trade-off between GHG emissions and benefits for electricity industry from EV charging at times of low demand. 相似文献
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Evaldo Costa Julia Seixas Gustavo Costa Thomas Turrentine 《International Journal of Sustainable Transportation》2017,11(7):518-525
The Brazilian cities as well as many of the large urban centers in the world continue to expand, increasing the demand for mobility and transport, while, at the same time, the same cities are investing in greenhouse gas (GHG) mitigation to avoid climate change. Brazil's urbanization rate increased from 26% in 1940 to almost 70% in 1980. During this period, the Brazilian population tripled and the urban population multiplied by seven. In 2010, the transport sector in São Paulo accounted for 71% of the total emissions released by the energy sector. Ethanol has been considered a fuel with less greenhouse gas emissions, when compared with fossil fuels. However, ethanol production would have to double to meet the expected demand. Electric vehicles (EVs) market is expanding around the world, and is also an option to reduce the transport emissions, if powered by clean electricity. To assess whether the adoption of EVs might bring more benefits than the current ethanol, we develop prospective scenarios supported by the Long-range Energy Alternatives Planning (LEAP) simulation tool, taking a bottom-up tank-to-wheel approach to consider the CO2 emissions of car in São Paulo. The scenario considering a substitution of 25% of gasoline-powered cars by EV in 2030 showed a reduction in energy consumption and CO2 emissions, around 15% and 26% respectively in that year in comparison with 2015. We discuss the interplay between ethanol and EV, also considering emission coefficients from life cycle analysis conducted in Brazil, and concluded EV will have higher positive impact on climate change mitigation than ethanol. 相似文献
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This paper analyzes how economic deregulation impacts firm strategies and environmental quality in the electric utility industry. We find evidence that the deregulation introduced to this historically staid industry has stimulated environmental differentiation. Differentiation is most likely to appear where its point of uniqueness is valued by customers, and we confirm this relationship in our sample. Specifically, utilities that served customers who exhibited higher levels of environmental sensitivity generated more ‘green’ power. The tendency for firms to differentiate in this way is lessened if they are relatively more dependent on coal‐fired generation or relatively more efficient. Thus, there is evidence that firms sort themselves into either differentiation or low‐cost strategies as the competitive realities of a deregulated world unfold. Deregulation and the ensuing environmental differentiation illustrate how utilities exploited formerly unmet customer demand for green power. The result has been greater levels of renewable generation and, hence, a cleaner environment. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献