共查询到17条相似文献,搜索用时 140 毫秒
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研究了铁钴钒软磁合金的铁芯损耗,发现铁芯损耗谱具有分形结构,讨论了带材厚度和磁感应强度对分形维数Df的影响。 相似文献
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详细介绍了大型水电站定子铁芯叠装完成后.铁芯磁化试验的目的、标准及步骤,方法。并以锦屏二级水电站7#机组为例,着重介绍了定予铁芯磁化试验参数选择、铁芯实际损耗及降低铁芯损耗的方法。 相似文献
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对Fe73.5Cu1Nb3Si13.5B9纳米晶铁芯分别进行普通热处理与横磁处理,并检测铁芯经两种热处理后的各项磁性能。获得了各频率下损耗与幅值磁密的关系。结果表明,横磁处理降低损耗效果较明显,该方法在高频电力电子变压器铁芯领域具有潜在应用前景。损耗分离结果表明,横磁处理后,磁滞损耗、涡流损耗、剩余损耗在总损耗中所占比例分别为不变、升高、降低。横磁处理后,磁畴结构改变,以磁矩旋转磁化为主要磁化方式,降低畴壁共振造成的异常损耗是除降低磁滞损耗外,降低总损耗的另一原因。 相似文献
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电机定子铁芯测试是确定电机定子铁损损耗的大小以及查找电机定子铁芯缺陷的重要试验。确定电机定子铁损损耗除了利用测量试验的电流、电压来计算外,另一种重要的手段就是通过测量电机定子铁芯在试验过程中的温升来 相似文献
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阐述几种离心式压缩机电机冷却方式,提出一种新型螺旋形冷却回路。对螺旋形冷却回路的损耗情况进行仿真分析,提出螺旋形冷却回路电机开设定子铁芯液态制冷剂流道的方案以降低转子带液的机械损耗。整机试验结果表明,开设定子铁芯液态制冷剂流道可以显著降低转子带液机械损耗,压缩机组能效提升约2%。 相似文献
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非晶合金凭借优异的综合软磁性能,尤其是在高频下有着极低的损耗而在高速电机领域备受关注。概述了非晶电机的优势和类型,综述了非晶定子铁芯的关键制备工艺,对比了径向叠压和轴向卷绕铁芯、模块拼接和整体成型铁芯以及有槽和无槽铁芯的各自优缺点。从退火处理、浸胶固化以及加工成型方式的角度总结了上述制备工艺对非晶带材和铁芯的性能影响。最后,结合非晶电机的最新研究进展,分析了当前非晶合金应用于电机定子铁芯存在的问题,并对未来非晶电机定子铁芯加工方法的发展进行了展望。 相似文献
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Yuriy I. Kuzmin 《Journal of Low Temperature Physics》2003,130(3-4):261-286
The effect of the fractal clusters of a normal phase, which act as pinning centers, on the dynamics of magnetic flux in percolative type-II superconductor is considered. The main features of these clusters are studied in detail: the cluster statistics is analyzed; the fractal dimension of their boundary is estimated; the distribution of critical currents is obtained, and its peculiarities are explored. It is found that there is the range of fractal dimension where this distribution has anomalous statistical properties, specifically, its dispersion becomes infinite. It is examined how the finite resolution capacity of the cluster geometric size measurement affects the estimated value of fractal dimension. The effect of fractal properties of the normal phase clusters on the electric field arisen from magnetic flux motion is investigated for the cluster area distribution of different kinds. The voltage-current characteristics of fractal superconducting structures in the resistive state are obtained for an arbitrary fractal dimension. It is revealed that the fractality of the boundaries of the normal phase clusters intensifies the magnetic flux trapping and thereby raises the critical current of a superconductor. 相似文献
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研究了合金元素对恒导磁微晶合金 Fe_(71)Co_7Si_9B_(13)的高频损耗及恒导磁特性的影响。发现碳(C)的加入能大大降低该合金的高频损耗。随着 C 含量的增加,高频损耗 P_(2/20k)单调下降,当 C 含量大于4(at)%后,P_(2/20k)不再随着 C 含量的增加而降低。该合金的等温 P_(2/20k~t_a)曲线(t_a 为保温时间)呈“U”型,属典型的微晶化效应降低损耗方式。x 射线衍射结果证明该合金的组织为 bcc 结构的α-Fe。认为 C 对损耗的影响机制不同于普通晶态合金中的李希特(Richter)效应。C 是易偏析元素,在微晶化热处理时,碳的偏析为细小α-Fe 的形成,提供了大量晶核,使合金的组织细化,从而细化了磁畴,降低了异常涡流损耗,使高频损耗降低并具有较高的动态导磁率。横向磁场热处理后该合金可成为优良的恒导磁电感材料 相似文献
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M. A. Vasyutin 《Technical Physics Letters》2011,37(8):743-745
The influence of a fractal character of the structure of an YBCO type high-temperature superconductor on its current-voltage
characteristic in a magnetic field has been studied. The fractal dimension and connectivity index of vortex transport channels
are determined as functions of the magnetic field strength. It is established that the glassy state index corresponds to that
of a vortex glass. 相似文献
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通过对比实验研究了改进的制备工艺下FINEMET纳米晶磁粉芯的磁性能,并探讨了其相应的物理机制。采用扫描电镜、透射电镜和X射线衍射仪检测磁粉的表面形貌、内部结构和晶格畸变,采用B-H分析仪检测磁粉芯的动态磁性能。结果表明,改进的制备工艺能够有效降低磁粉芯的损耗,提高磁导率和频率应用范围。延长非晶粉末的球磨时间能够降低磁粉芯的磁滞损耗和涡流损耗,最佳的球磨时间为8h。通过对比磁粉的晶格畸变,发现通过改进工艺制备的磁粉的晶格畸变相对较小,该工艺提高磁性能的原因在于磁粉残余内应力的有效释放。 相似文献
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H. J. Liu H. L. Su W. B. Geng Z. G. Sun T. T. Song X. C. Tong Z. Q. Zou Y. C. Wu Y. W. Du 《Journal of Superconductivity and Novel Magnetism》2016,29(2):463-468
The Fe-Si-Al soft magnetic powder cores with five particle size distributions were prepared. The microstructure study revealed that the cores had a fairly compacted structure with a uniform insulation layer of the phosphate forming on the surface of the magnetic particles. The particle size distribution was found to have the great influence on the core’s magnetic properties. The increase of the percentage of the small particles results in the decrease of the effective permeability, the improvement of the DC-bias performance, and the deterioration of the core loss. The effects of the distributed air gap and the demagnetization field on the core’s magnetizing process were believed to be the underlying physical origins. The core losses at the frequencies lower and higher than 150 kHz were found to be mainly determined by the hysteresis loss and the eddy-current loss, respectively. The good magnetic performances of the Fe-Si-Al powder cores with the effective permeability of about 55–60 were finally achieved as follows: the percent permeability at 100 Oe is up to 52.3 %, and the lowest core loss at 50 kHz/1000 Gs is 270 mW cm?3. 相似文献