共查询到20条相似文献,搜索用时 125 毫秒
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论述了利用0MRON PLC实现几种不同现场要求的控制方案的优缺点及设计方法。在逆行方案选择时,除了考虑工业现场的实际情况外,还要考虑方案的可靠性.经济性.灵活性和实用性。 相似文献
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提出了一种新型同步、步进驱动系统方案,并利用谐波平衡原理对电机稳态运行时电流、转矩及其各次谐波分量进行了计算.计算结果表明,该系统方案是可行的. 相似文献
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本文对含大纯滞后的对象,就采样调节和Smith预估补偿两种方案进行了分析与比较,意在通过实验来探讨两种方案的应用效果和适用场合. 相似文献
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“1 1”并机冗余方案是实际使用较多的一种UPS供电方案.但该方案并不是十全十美,通过“1 1”并机系统和单机双母线系统方案对比.推荐客户在核心设备上使用可靠性更高的单机双总线方案。 相似文献
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金沙江大容量水电远距离输送方式的选择 总被引:1,自引:1,他引:1
论述金沙江流域大容量水电远距离外送面临的挑战和输电方案的选择,特别是交流高压输电与直流高压输电方案的比较,按照全国电网互联的战略规划.毕中-川渝电网应发展成为区域同步电网而不是混合电网。从合理的电网结构考虑,交流输电方案比直流输电方案更具竞争力。同时.从对区域电力市场运营的适应性.电网可靠性和灵活性、技术成熟性、国际运行经验以及技术设备本地化的角度,对交流/直流两种方案作了评价。推荐采用750kV交流超高压送出.同时通过区城电网之间直流联络线转送的方案。 相似文献
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燃煤电厂静电除尘器改造方案 总被引:11,自引:0,他引:11
随着我国环保标准日益严格,很多燃煤电厂静电除尘器已不能满足排放标准的要求,需进行改造。该文首先分析了造成静电除尘器除尘效率低下的主要原因;提出3种改造方案:增加电场;改造为袋式除尘器;改造为静电袋式复合除尘器。并从技术性能和经济性2个方面对3种改造方案进行了比较.以郑州热电厂200MW机组静电除尘器改造为例对3种方案进行了对比分析.结果表明:改造为静电袋式复合降尘器的方案是静电除虫器改造的最佳方案,并认为静电袋式复合除尘是我国除尘技术来来的发展方向之一。 相似文献
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在分析永磁同步电机(PMSM)直接转矩控制理论的基础上.介绍了一种基于DSP及智能功率模快(IPM)的直接转矩控制系统实现方案.详述了该方案的硬件结构和软件设计。系统采用TMS320LF2407构成核心控制电路,以智能功率模块PM30CSJ060构成逆变主电路。实验运行表明.方案合理.结构通用紧凑。 相似文献
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《Industry Applications, IEEE Transactions on》1991,27(2):346-349
C. Patak maintains that the motor analyzed by L. Xu et al. in the above-titled paper (see ibid., vol.26, no.2, p.229-36 (1990)) cannot operate as specified by the authors. R.M. Davis, in a separate discussion points out that the above-titled paper is based on earlier work by L. Xu and T.A. Lipo (1987, 1988) that had prompted him to publish a paper in which he reached a completely opposite conclusion, and that L. Xu et al. have neither noted nor referenced his work. In reply, L. Xu et al. point out that Patak has been misled by Fig. 4 of their paper and provide clarification. They also explain why they did not consider Davis's paper and rebut his arguments. They also note that the captions for Figs. 14 and 15 of their paper should be reversed 相似文献
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介绍一种在瓦楞纸板生产线上能自动调节原纸张力的张力测控装置,该装置由单片机控制电控气动比例阀的输出气压,由使用该气压进行制动的气刹来调节张力的大小,在整个生产过程中,使原纸始终处于恒张力的状态下,从而消除了断纸现象. 相似文献
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微网运行控制策略的研究 总被引:1,自引:0,他引:1
主要研究了微网运行的3种控制方法。根据功率型电源发电功率受环境影响的特点,在并网时对其采用P-Q控制;对主控型电源,在孤岛运行时对其采用V-f控制;同时对同种多个并联电源采用Droop下垂控制。综合3种方法建立一个比较理想的控制策略来实现最终的控制效果,并建立简单微网模型,在Matlab/Simulink环境下进行微网并网、孤岛状态转换、负荷切投等不同工况的仿真,验证控制策略的有效性。 相似文献
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《Power Delivery, IEEE Transactions on》1999,14(4):1359-1367
This paper describes the analysis of thermally accelerated aged insulation samples to investigate the degradation processes observed in the insulation of aged transformers. Accelerated ageing experiments were performed on paper wrapped insulated conductors in the presence of air and nitrogen environments over a temperature range of 115 to 145°C. Effects of oxidation on the ageing of oil-paper insulation were investigated and results are presented in this paper. The condition of aged insulation samples was investigated by a number of diagnostic techniques: (a) measurements of interfacial polarization spectra by the return voltage method, (b) measurements of molecular weight and its distribution by gel permeation chromatography, (c) surface analysis by X-ray photo-electron spectroscopy, and (d) a study of the oxidation of the oil by UV-visible spectroscopy. Results from these measurements are presented in this paper and are used to analyse the degradation process with special emphasis on oxidation 相似文献
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睡眠和看门狗是在很多单片机应用领域都广泛采用的节约功耗的方法.本文首先介绍胎压报警系统的总体监控流程和系统的应用前景,分胎压监控流程对电源能耗的严重影响减少了装置的使用寿命,并提出使用睡眠功能和看门狗定时的方法. 相似文献
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Saha T.K. Darveniza M. Hill D.J.T. Le T.T. 《Power Delivery, IEEE Transactions on》1997,12(4):1547-1554
This paper describes the application of two relatively new diagnostic techniques for the determination of insulation condition in aged transformers. The techniques are: (a) measurements of interfacial polarization spectra by a DC method; and (b) measurements of molecular weight and its distribution by gel permeation chromatography. Several other electrical properties of the cellulose polymer were also investigated. Samples were obtained from a retired power transformer and they were analysed by the developed techniques. Six distribution transformers were also tested with the interfacial polarization spectra measurement technique, and the molecular weight of paper/pressboard samples from these transformers were also measured by the gel permeation chromatography. The variation of the results through different locations in a power transformer is discussed in this paper. The possible correlation between different measured properties was investigated and discussed in this paper 相似文献