A three level double-ended forward converter

A new four-switch converter topology is presented. This topology is intended for use in high input voltage (900 V-1200 V) and low power applications (≅ 150 W), specially auxiliary power supplies. Its main advantage is the off-voltage stress reduction on the switches at half of the input voltage. It works in a similar way like the classical double-ended forward converter. The four switches can be set on with the same gate pulse, with a small delay time in the off signal of the internal switches after the external ones. This position prevents direct short circuit in the DC link. This reliability and the simplicity of the way it is commanded, makes this converter very suitable for auxiliary power supplies applications. We present the principle of operation of the proposed converter. Each stage with the main characteristics, and the main equations are also presented. Consistent simulation results with a project example are showed. Experimental data shows the suitability of the proposed converter.