排序方式: 共有62条查询结果,搜索用时 450 毫秒
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本文结合不对称半桥倍流整流变换器.介绍了两个电感与一个变压器的集成。通过集成磁件的变换,给出了磁集成的两种方式,即正向耦合方式与反向耦合方式。理论分析和PSpice仿真验证了反向耦合方式在磁芯体积和功率损耗减小方面具有优势,在变换器效率上反向耦合方式也明显高于正向耦合方式。 相似文献
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金属介质对射频信号的干扰一直以来影响着射频识别技术(RFID)的有效应用。为了研究导致干扰发生的机理以及解决办法,以超高频段RFID系统为对象,依据电磁场相关理论,进行了一系列实验。通过对实验所得数据的分析,验证了金属介质对RFID被动标签读取率的影响,并进一步发现标签和金属介质表面间隔距离与读取率之间的变化关系。另外,发现了附加金属层产生的同相位电场对标签读取性能的放大作用。最后,根据实验研究结果,提出一种可用于金属表面的RFID被动标签的设计方案,该设计方案不但可以有效消除金属干扰的负面影响,还可在原有读取性能的基础上进一步提高读取率,同时兼顾使用方便性和制造成本两方面。 相似文献
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Dalibor Cvoric Domenico Lahaye Sjoerd deHaan Braham Ferreira 《International Journal of Numerical Modelling》2016,29(2):354-360
Due to increasing levels of fault currents, fault current limiters (FCLs) are expected to play an important role in the protection of future power grids. Inductive saturable FCLs are particularly interesting due to their inherent reaction on the fault. Many different configurations have been proposed in literature. Being difficult or impossible to create accurate analytical models of some FCL configurations, the development of finite element (FE) models for inductive FCLs is required. This paper presents a 3D nonlinear transient FE modeling technique applied to two inductive FCLs, namely the so‐called open‐core and three‐leg single‐core FCLs. The models have been validated by comparing simulation results with lab measurements. Results show excellent agreement. The models constitute a valuable tool for design, optimization, and verification of inductive FCLs. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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传统双Boost无桥PFC(power factor correction)变换器去除了整流桥结构,变换器效率得到了提高,但由于需要两个电感,整个系统功率密度小,体积大。分析了四种磁集成技术,并采用了一种中柱低磁阻磁路电感集成方式,将双Boost无桥PFC变换器的两个电感集成来缩减系统体积,通过分析和计算,该电路拓扑避免了环流问题。采用了改进无差拍控制算法来消除采样和计算延迟所带来的控制偏差,提升了输入电流的控制精度。最后搭建了一台750W的实验样机,验证了理论分析的正确性。 相似文献
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评述了大功率磁性技术中软磁材料的近十年发展史,所介绍的材料包括:硅钢、坡莫合金、软磁铁氧体、非晶和纳米晶合金、软磁复合材料等,并且分析了发展中的一些问题。 相似文献
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M. Yabumoto S. Arai R. Kawamata M. Mizokami T. Kubota 《Journal of Materials Engineering and Performance》1997,6(6):713-721
For precise evaluations of magnetostriction properties, a new magnetostriction measuring system using a laser vibrometer was
developed. Frequency analysis of magnetostriction under non-sinusoidal magnetization revealed a nonlinear relation between
harmonics in flux and those in magnetostriction. Transformer core vibration was investigated in order to clarify the relations
between magnetostriction and transformer noise and to realize low-noise transformers. Resonance was proved to have an important
role for core vibration. Domain-refined, grain-oriented electrical steel, which fulfills low loss and low magnetostriction
properties simultaneously, is also explained. 相似文献
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