Improved Current Shunt Characterization Method for Core Loss Measurement
With the increasing switching frequencies and power densities in modern power converters, magnetic core losses are becoming more essential for efficiency and thermal optimization. Traditionally, the two-winding method suffers from sensitivity to phase error in practical measurements; this is mainly created by the unknown phase shift of a current-sensing resistor. Several methods have been developed to characterize the phase shift of a current shunt resistor; however, the load effects of oscilloscopes are ignored. As a result, the corresponding phase shift can be significantly underestimated. This paper proposes an improved method for phase shift extraction of a current shunt to solve the problem. The effectiveness of the shunt characterization method is experimentally verified up to 50 MHz. Benefits from the proposed method, the time-consuming component tuning process is not required for core loss measurement. A measurement verification at 10 MHz shows its validity. Finally, a current shunt implemented with a coaxial resistor array is designed with a phase shift of 0.05⁰ at 10 MHz and a parasitic inductance as low as 42 pH.
A. Huang et al., "Improved Current Shunt Characterization Method for Core Loss Measurement," IEEE Transactions on Power Electronics, Institute of Electrical and Electronics Engineers (IEEE), Feb 2022.
The definitive version is available at https://doi.org/10.1109/TPEL.2022.3150003
Electrical and Computer Engineering
Electromagnetic Compatibility (EMC) Laboratory
Keywords and Phrases
Coaxial Resistor; Core Loss; Core Loss; Current Measurement; Current-To-Voltage Impedance; Impedance; Loss Measurement; Resistors; Transmission Line Measurements; Two-Port Resistor; Voltage Measurement
International Standard Serial Number (ISSN)
Article - Journal
© 2022 Institute of Electrical and Electronics Engineers (IEEE), All rights reserved.
10 Feb 2022