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