In this paper, we develop and demonstrate an automatable core loss testing method which replaces the commonly employed RF power amplifier with a high frequency switching inverter. An analytical framework for assessing flux harmonics in the core is also presented. It discusses the theory calculation for switch losses, inductor losses, input and output capacitor ESR losses, and other losses, as well as their effect to the efficiency of a synchronous buck converter. The current is passed thru the center of the laminations via the rotor shaft instead of using the “LOOP CABLE”. An experimental demonstration is. 2. Theoretical Max Rates 512 64 1280 1518The loop test was narrow in THINNER tion behavior.