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农网在运行时,由于内、外界因素,可能引起故障,造成对用户供电中断。装设自动重合闸装置可以提高电力系统供电可靠性。该文介绍了巴彦淖尔农村电网自动重合闸装置工作原理、投运现状、发展前景及经济效益分析。 相似文献
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10kV柱上开关在农网线路上的合理应用,为供电企业提高供电可靠性立下了汗马功劳。该文针对农网线路的结构与故障性质,应选用不同型式的10kV柱上开关设备。 相似文献
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<正>为提高供电可靠性,某地区电网加大配电自动化的研究及推广力度,其中电压型分段器在某地区配网线路大力建设,有效减少了配网线路故障引起的停电范围。本文对电压型分段器原理进行介绍,并对整定原则进行说明,以及对一起分段器在应用过程中未正确得电合闸事件进行分析及改进。1电压型分段器原理介绍电压型分段器具备有电延时合闸、无电自动分闸,以及根据得电与失电时间情况闭锁合闸的功能。与变电站出口开关重合闸功能配合,电压型分段器能有效隔离故障线 相似文献
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为适应农村用电需求快速增长的趋势,提升农网供电可靠性和供电能力,促进农村经济社会发展,国家计划利用三年时间实施新一轮农网改造升级工程。由于农网改造升级工程任务重、时间紧,为顺利实施工程,利用好农网改造资金,笔者认为在工程实施过程中应加强各个环节的管理。 相似文献
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陕西省延安市供电公司"一区两县"10kV线路125条,10kV线路分段开关208台,10kV公用配电变压器2423台,其中:市辖供电区公用配电变压器1042台,容量为42.27MVA,县级供电区公用配电变压器1381台容量为60.2MVA。经过一、二期农网建设与改造、中西部农网完善、农网改造升级工程的实施,延安市"一区两县"农配网网络结构得到进一步优化和完 相似文献
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<正>在农网和城网改造中,推广使用剩余电流动作保护器(RCD),极大地提高了安全用电水平。但在长期的使用过程中,经常出现剩余电流动作保护器三次自动重合闸失败而闭锁的情况,需人工送电。为此,笔者设计了一套时间可调的自动重合闸装置,提高了恢复送电的可靠性和及时 相似文献
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感官检验棉花的品级,这是农村常见的一种检测手段.它的一个主要特点就是存在不确定性.这是由于检验员的品级检验水平存在一定的差异,其中有很多因素制约着检验的结果.文章对影响感官检验结果的因素进行了系统的分析. 相似文献
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《Journal of Agricultural Engineering Research》1998,69(3):249-254
A model to represent the discolouration of dried powder of carrots as a function of temperature was developed. Two types of carrots, Asian and European, containing large amount of lycopene and β-carotene, respectively, were tested. The dried powder was stored under an atmosphere with O2and at three different temperatures, 5,20 and 35°C. The surface colour of the powder was monitored during storage by a Hunter colour ratioa/b. In the proposed model, the rate of oxidation was assumed to be represented by the product of the fraction of concentration of oxidized pigment at arbitrary time and a specific rate of oxidation of pigment. The rate parameters in the proposed model were calculated by fitting the experimental data with smooth curves by trial and error at the end of the induction period but before discolouration took place. The frequency constant and activation energy, expressing the temperature dependence of the rate parameters, were expressed by the Arrhenius relation. The simulation results of a Hunter colour ratioa/bof dried powder at 25°C showed good agreement with the experimental data, suggesting that the proposed model was effective for the prediction of discolouration of dried powder of both types of carrot. The use of the induction period in the manner described may enable the shelf life of dried powder to be predicted. 相似文献
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从灾害经济学的角度探讨了城镇供水优化调度的必要性和可能性,认为在缺水不可避免的情况下,对供水进行优化调度可以减小缺水带来的损失,产生较好的减灾效益,特别是可以大大减小严重干旱的灾害效应。并根据水资源的特性,提出了缺水损失的计算模式以及优化调度的原则和方法。 相似文献
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The fractional outflow rate of water from the rumen, measured as the rate of disappearance of the chromium complex of ethylenediamine tetra-acetic acid, was related to a number of dietary factors. A multiple regression equation was derived which expressed fractional outflow rate as a function of the intakes of dry matter, ash, acid-detergent fibre and crude protein.The data analysed consisted of 243 observations for sheep on 59 diets, including forage, concentrate and mixed diets. The ranges covered by the data were: fractional outflow rate 0.7–3.6 day?1; dry matter intake 560–1400g/day; ash 4–30%, acid-detergent fibre 7–41%, crude protein 5–26 % of dry matter; there were no observations for sheep of less than 34 kg liveweight.The equation accounted for 56·3 % of the total variance. Between-sheep variance could not be calculated for the whole of the data but was undoubtedly substantial since, for a sixth of the data, it was known to account for 38 % of the total variance. 相似文献