基于低测试阻抗角的高频电感绕组损耗测试与分析

The test and analysis of winding losses of high-frequency inductor based on low test impedance angle

随着第三代半导体功率器件的迅速发展,功率变换器中更高频磁元件的应用将越来越普及,国内外频率高达MHz的磁元件损耗评测量鲜有研究。现有高频绕组损耗测量方法难以体现磁元件实际工况对绕组损耗的影响。通过深入分析传统交流功率测量法在高频磁元件损耗测量的主要影响因素,提出一种可以降低测量阻抗角的高频电感绕组损耗测量电路和方法,详细论述了测量电路的工作原理,研究测量过程影响测量精度的关键因素。采用3D打印的环形骨架制作的空心电感作为被测电感,进行了不同频率下绕组损耗测量的实验。实验结果表明,所提方法可以有效地减小测量阻抗角,实现高频励磁下绕组损耗的准确测量,且在频率50~700 kHz范围内与阻抗分析仪测量的损耗偏差在10%以内。

With the rapid development of third-generation semiconductor power devices, the application of higher frequency magnetics in power converters is becoming more and more popular, and there are still very few evaluation techniques for magnetics losses with frequencies up to MHz in the field of high frequency magnetics. The existing measurement methods of high-frequency winding loss can hardly reflect the influence on magnetics winding losses under actual working conditions. The main influencing factors of conventional AC power measurement method for measuring highfrequency magnetics losses are analyzed deeply. A measurement circuit and method for high-frequency inductor winding losses is proposed, which can reduce the impedance angle, and the operating principle of measurement circuit is discussed in detail, the key factors affecting the measurement accuracy in the measurement process are studied. The air-core inductor made of the 3D printed toroidal bobbin is used as the inductor under test, and the winding losses is measured at different frequencies. The experimental results show that the proposed method can effectively reduce the measured impedance angle and realize the accurate measurement of winding losses under high-frequency excitation. Furthermore, compared with the loss measured by impedance analyzer method, the error is less than 10 % in the frequency range of 50-700 kHz.