Power loss measurement and evaluation form the foundation of loss modeling and optimization. This paper introduces a method for evaluating power loss in high-frequency transformers operating under forced air-cooling conditions, simply based on surface temperature measurement with a thermal camera. Our approach establishes a direct correlation between power loss and surface temperature, utilizing a simplified thermal network. This method enables the measurement of both total loss and individual core loss and winding loss for high-frequency transformers operating in any working condition. To verify the precision of the evaluated power loss, experiments are conducted on a prototype high-frequency transformer.
