An Integrated Testbed with Single DC Source for Delivering Symmetrical Square-Wave Excitation Voltage in the Triple Pulse Test

While the conventional methods are based on sinusoidal excitations to parameterize the loss of magnetic components, recent studies have justified the characterization directly through large-signal, rectangular excitations, as are experienced in typical power electronics converters. The Triple Pulse Test (TPT) has been proposed previously for this purpose as a discontinuous procedure to characterize the high-frequency loss of magnetics. The excitation circuit used to deliver the TPT is advanced in this paper by removing the need for two external power supplies. Instead, a single power supply is connected to a voltage-offsetting input stage which uses a novel implementation of a half-bridge circuit to deliver a controllable offset between two capacitor banks. This dc-link offsetting circuit can compensate the asymmetric voltage drops on the power devices and delivers rectangular voltages with symmetric amplitude to form closed BH loops on the device under test. The aim is for the integrated testbed is to deliver the TPT autonomously, iterating over several operating points, to generate a loss map of one magnetic component. This testbed could subsequently aid the manufacturer of magnetics to shift from material-based datasheet to component-based, which will enable the end users to model high-frequency magnetics more easily and accurately.