Results 11 to 20 of about 3,930 (119)
Gaoya dianqi, 2019 基于全桥MMC的柔性直流输电系统,能迅速隔离直流线路故障,得到了广泛的应用。损耗是衡量换流阀的重要指标,文中对基于全桥MMC换流阀的损耗进行分析,运用分段解析计算的方法给出具体的计算表达式。首先,将MMC换流阀的总损耗分为通态损耗和开关损耗两部分。然后,根据桥臂电流的方向,桥臂电压与投入子模块个数之间的关系,运用分段解析方法得到MMC换流阀的通态损耗;之后,根据每个子模块投切状态变化对应的能量损耗进行分段解析计算,求得MMC换流阀的开关损耗;将这两部分损耗进行综合,从而得出基于全桥MMC换流阀的总损耗 ...
荣飞 +4 more
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Rare Metals, Volume 45, Issue 8, August 2026.ABSTRACT Many metallic components are frequently subjected to coupled environments of friction and vibration, stemming from interfacial contact and relative motion between mating parts or external stimuli. Consequently, it is imperative for these components to exhibit a synergy of high wear resistance and superior damping properties.
Ze Pu +12 more
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Guangtongxin yanjiu, 2006 文章给出了多包层标准单模光纤的宏弯曲损耗模型,这一损耗模型不仅适用于多包层单模光纤的宏弯曲损耗的计算,也适用于单包层单模光纤的宏弯曲损耗的计算。文章还讨论了弯曲半径及工作波长与单模光纤弯曲损耗之间的关系,并把这种关系与传统的弯曲损耗模型进行了比较,比较结果表明,单模光纤包层对弯曲损耗有很大的影响。此外,文章还运用模式耦合理论详细解释了廊（Whispering-gallery,WG）模对损耗振荡的影响。
王建飞, 王高刚, 张逸新
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Rare Metals, Volume 45, Issue 7, July 2026.ABSTRACT The composition and structural characteristics of metacomposites are crucial for tuning their negative electromagnetic parameters; however, the lack of a clear structure–property relationship severely limits their application in dielectric and magnetic fields.
Chunyuan Deng +9 more
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Guangtongxin yanjiu, 1994 本文报道一种高回波损耗单模光纤斜面连接端子。用高斯光束耦合理论分析了其回波损耗特性。实验中测得该端子插入损耗小于０．６ｄＢ，回波损耗大于５３ｄＢ。理论研究指出，单模光纤斜面连接是研制高回波损耗光无源器件的有效方法。
江山, 刘水华, 方罗珍, 许远忠
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Rare Metals, Volume 45, Issue 7, July 2026.ABSTRACT Ti3C2Tx MXene shows significant potential in the field of electromagnetic wave absorption; however, the wave absorption performance was hindered due to the impedance mismatch, which was caused by its inherent high dielectric constant. In this work, Ti3C2Tx MXene co‐assembled with molybdenum disulfide nanosheets and carbon coating layers (MXene/
Hualong Yu +11 more
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Rare Metals, Volume 45, Issue 7, July 2026.ABSTRACT High‐entropy oxides (HEOs) are promising for microwave absorption but suffer from a trade‐off between impedance matching and attenuation, often requiring high filling ratios (> 50 wt%). Herein, we propose a “lattice‐spin” dual‐regulation strategy by introducing giant‐radius Bi into a single‐phase HEO solid solution.
Junwei Zhang +11 more
wiley +1 more source
Gaoya dianqi, 2019 损耗是衡量柔性直流输电系统性能的关键指标之一。对调制波叠加三次谐波可以提高换流阀直流电压利用率,还可以增大换流阀的冗余度,提高可靠性。推导了叠加三次谐波后换流阀的损耗计算公式,详细分析了三次谐波叠加率对换流阀损耗的影响。计算结果表明,随着三次谐波叠加率的增大,换流阀损耗逐渐降低,但是此时的冗余度与损耗并不是最优值,因此通过遗传算法对损耗与冗余度进行了优化配置以兼顾损耗与冗余度。结果表明:当三次谐波叠加量达到24.3%时的时候损耗与冗余度取得性能平衡,此时总损耗为1.485%,冗余度为12.7%。
荣飞 +4 more
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Rare Metals, Volume 45, Issue 6, June 2026.ABSTRACT Electromagnetic wave absorption materials require high dielectric loss and excellent impedance matching performance. However, current conventional biomass‐derived electromagnetic wave absorption materials are still limited by low electrical conductivity and a single structure.
Yue Zhang +9 more
wiley +1 more source
Dianci bileiqi, 2008 输电线路电压等级越高,地线上的电能损耗就越大,如何降低地线损耗意义重大。分析了电能在地线中产生损耗的原因,通过EMTP仿真计算了在各种情况下电能损耗,比较了采用地线分段后的效果,得出:对750 kV输电线路采用分段绝缘的绝缘方式,有效地减小地线上的感应电流,使地线的损耗降抵为地线两端直接接地时的99%以上;三相负载平衡程度越小,地线产生损耗会越大,应尽量保证系统三相负载平衡;适当调整接地电阻的大小可以优化地线电能损耗;输电线路长度增加,地线损耗和地线上的感应电压也增大,应选取合适的分段距离 ...
张亚婷, 高博, 施围
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