High power resonant topology for DC-DC converter

The paper presents a resonant DC-DC converter topology for the first stage of a two-stage converter to link a renewable energy source to a utility grid. For reliable input to a grid the inverter needs a stiff input Dc voltage. To minimize switching loss and avoid switching over voltages a resonant converter is used. This also has the advantage of minimizing EMC. To gain the necessary DC voltage at the inverter input, it is necessary to use a DC/DC step-up converter. The necessary requirements are met with an H-bridge converter. Connected to the output of the converter is a series combination of the transformer primary and a capacitor such that the capacitor resonates with the transformer´s leakage inductance at the switching frequency. The transformer´s output is rectified and filtered for input to the inverter. Results from simulation tests confirm the current´s resonant pattern. Yet further results are shown of the converter´s performance at different loadings to confirm the zero-current switching effects. It is concluded that this converter topology provides a reliable basis for the application under consideration. Further analysis confirms its wider applicability