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针对传统的故障指示器使用铁芯式电流互感器体积较大、高频特性不佳,不能满足配网故障电流检测需要的问题,基于罗氏线圈的工作原理,设计了多片组合式PCB型罗氏线圈及后端积分放大电路,建立了PCB型罗氏线圈电流互感器传递函数模型并通过Matlab进行仿真,制作了PCB型罗氏线圈电流互感器实物并进行试验测试其性能。结果表明,PCB型罗氏线圈电流互感器不仅可准确反映工频电流大小,同时还具备良好的高频特性,能够满足配电网故障定位的测量需求。 相似文献
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对于通过前端浪涌防护模块对数字电源浪涌冲击进行抑制的方法,当浪涌能量过高时,存在浪涌防护模块通常无法有效抑制全部浪涌能量的问题。针对该问题,分析了浪涌的产生原因及特性,研究了浪涌在数字电源中的传递路径及在不同观测点的浪涌波形,进而提出了印刷电路板(Printed circuit board,PCB)布局优化、电路优化及磁屏蔽等数字电源浪涌抑制新方法。所提新方法原理简单、可靠性高,能使数字电源获得良好的浪涌抑制能力。研制了1.2k W试验样机并进行浪涌测试试验,试验结果表明所提出的浪涌抑制新方法可抗4级浪涌试验,能够保障数字电源正常工作。 相似文献
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江阴兴澄特种钢铁有限公司 《节能与环保》2006,(11):52-53
2006年2月16日的《中国冶金报》刊登中国金属学会题为《谁是2005年的领跑者》的权威文章,:公布了2005年我国钢铁生产指标之最,在电炉生产一栏中,兴澄特钢以235千瓦时/吨名列全国电炉生产综合电耗最低. 相似文献
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Due to huge-power aircraft development and more electronic devices applied onboard,high heat flow density and uneven thermal distribution are becoming new problems.One new try is adding an air-lubricating oil radiator as the secondary cooling component but there are still few reports on its research.Therefore,this paper proposes a newly-design plate-fin air-lubricating oil radiator different from tube-fin or shell-tube conventionally used in previous engine system.This radiator is arc,and equipped in internal surface of air intake.Numerical and experimental analyses were carried out on fin performance.Their results agreed well with average error of 13%on thermal resistance.Then heat and flow behaviors of oil side were presented with different structures and sizes of flowing passage.According to all research,optimized radiator is gained with fin spacing of 3.76 mm,fin thickness of 2 mm,single flowing path with width of 13 mm and gradient inlet and outlet.Its heat dissipation of 28.35 k W and pressure loss of 2.2 MPa can meet actual working requirements.The research proves an air-lubricating oil radiator with arc structure and layout mode of internal surface to be feasible,which is a new but efficient cooling scheme and can lead to an innovative but wide use in modern aircrafts. 相似文献
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5月6日,中国残奥委、中国残疾人事业新闻宣传促进会在人民大会堂联合举行新闻发布会宣布,我国能源行业新贵江苏太阳雨太阳能集团成为残奥助威团全程独家合作伙伴,在圣火传递中感动全球的残疾人运动员金晶成为"残奥助威团"的形象大使. 相似文献
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1341材料在循环水泵上的应用 总被引:1,自引:0,他引:1
对热电厂发电机的三台循环水泵的运行状况进行了分析,并用BELZONA1341材料对水泵叶轮的表面进行了处理,减少了叶轮表面与水流的阻力和涡流的产生,降低了电机的有功电流,节约了电能,并且延长设备的寿命,效果十分明显. 相似文献
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The temperature uniformity and component concentration distributions in solid oxide fuel cells during operating processes can influence the cell electrochemical and thermal characteristics.A three-dimensional thermal-fluid numerical model including electrochemical reactions and water-gas-shift(WGS)reaction for a single channel solid oxide fuel cell was developed to study the steady-state characteristics,which include distributions of the temperature(T),temperature gradient((35)T/(35)x),and fuel utilization.It was shown that the maximum temperature(Tmax)changed with operating voltage and the maximum temperature gradient(((35)T/(35)x)max)occurred at the inlet of the channel of a solid oxide fuel cell by simulation.Moreover,the natural convection condition had a great influence on T and(35)T/(35)x.The thermal stress generated by temperature differences was the key parameter and increasing the convection heat-transfer coefficient can greatly reduce the thermal stress.In addition,the results also showed that there were lower temperature gradients and lower current density at high working voltage;therefore,choosing the proper operating voltage can obtain better cell performance. 相似文献
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随着中国经济的飞速发展,能源短缺,环境污染等问题日益严重.欧美等发达国家早已开始着手解决这些问题,每年都有大量来自于政府、企业和风险投资的资金用于清洁技术的研究与应用.根据道琼斯数据显示,2007年在清洁技术领域,全球共发生了221项投资案例,投资总额达30亿美元,比2006年增长了43%. 相似文献
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第十七届世界国际氢能大会于2008年6月15日~19日在澳大利亚布里斯班市举行,来自全世界44个国家的600余位代表聚集一堂,讨论当代氧能技术和发展趋势. 相似文献
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