New High-Frequency Core Loss Measurement Method With Partial Cancellation Concept

As an essential part in a power converter, the magnetic cores and their design play an important role in achieving high efficiency and high power density. Accurate measurement of the core loss is important to their optimization. To improve the measurement accuracy (especially at high frequencies), previous methods proposed to cancel the reactive voltage of the testing core by using a cancellation capacitor or inductor. However, the value of the cancellation component is critical, and a small variation can induce a big measurement error, so extra effort is required to fine-tune the cancellation component value, which is a very time-consuming process and makes the standardization of the measurement instrument almost impossible. This paper presents a new measurement method with a partial cancellation concept that enables accurate core loss measurement for arbitrary wave excitation without the requirement to fine-tune the cancellation component value. The proposed method is experimentally verified up to 10 MHz.