DC inductor loss measurement used in DC/DC converters under high DC current conditions

This paper presents a DC inductor loss measurement system that is used in high-power DC/DC converter applications. However, accurate DC inductor loss measurement under high-power DC/DC converter excitation has been a significant challenge due to phase error problems between the high-voltage and high-current sensors. Therefore, the authors developed a high-power DC inductor excitation system and a new phase error compensation method to enhance measurement accuracy. The DC inductor excitation circuit can emulate the excitation of a maximum 120 kVA equivalent application by regenerating power. The phase errors, including the A/D timing difference in the digital sample recorder, are corrected over a wide range with the largest phase error being 0.013. The loss measurement error percentage is theoretically less than 0.56% in the test DC inductor. Furthermore, the measurement accuracy is verified using state-of-the-art loss analysis, including both FEM analysis and iron loss data mapping for power electronics applications.