Loyau V, Lo Bue M, Mazaleyrat F
SATIE UMR 8029 CNRS, ENS Cachan, PRES UniverSud, 61 Avenue du President Wilson, 94235 Cachan Cedex, France.
Rev Sci Instrum. 2009 Feb;80(2):024703. doi: 10.1063/1.3079382.
Classically, low frequency losses in soft magnetic materials and ferrites in particular are measured by flux metric method under sinusoidal waveform excitation voltage. However, in typical application of modern power electronics, the frequency currently exceeds 100 kHz. This feature is at the origin of a difficulty: the phase shift between current and voltage can be disturbed by current probe delay. Thus, the results can be affected by large errors. As a consequence, it becomes more and more important to develop alternative methods to measure losses in magnetic materials. It is proposed to use calorimetric method which is by principle free of the above mentioned problems. The experimental device is described in details and the results are reported for experiments conducted on a commercial Mn-Zn ferrite under sinusoidal waveform regime for frequencies varying from 10 to 200 kHz. Comparisons with flux metric measurement show that significant differences appear typically for Bf products above 5000 V/m(2) (50 kHzx100 mT).
传统上，软磁材料尤其是铁氧体的低频损耗是在正弦波形激励电压下通过磁通度量法测量的。然而，在现代电力电子的典型应用中，当前频率超过100kHz。这一特性带来了一个难题：电流和电压之间的相位偏移可能会受到电流探头延迟的干扰。因此，结果可能会受到较大误差的影响。所以，开发测量磁性材料损耗的替代方法变得越来越重要。有人提议使用量热法，该方法原则上不存在上述问题。详细描述了实验装置，并报告了在正弦波形状态下，对一种商用锰锌铁氧体在10至200kHz频率范围内进行实验的结果。与磁通度量测量的比较表明，对于Bf乘积高于5000V/m²（50kHz×100mT）的情况，通常会出现显著差异。
