Investigate and Improve the Distorted Waveforms for Core Loss Measurement with Arbitrary Excitations

The magnetic core plays a very important role in high frequency switching transformer modeling, design as well as loss estimation, etc. Extract the core loss from the winding loss accurately is essential in many industrial applications. Usually, A power amplifier connected to a function generator is applied to add the excitation to the CUT (core under test). For practical applications, sometimes, a square-wave or triangular-wave excitation, which depends on the working condition, is required to be added to the CUT. However, sometimes, it is found the non-sinusoidal excitations added on the CUT are distorted, which brings difficulties to accurate core loss measurement. In this paper, a detailed explanation for this phenomenon is given, several convenient solutions to improve the non-sinusoidal waveforms are explored based on the theoretical analysis. Both the simulation and experiment verify the analysis.