Non-isolated Inductor-less Soft-Switching Bus Converter with Self-Driven

This invention proposes a simple topology for the first stage of non-isolated two-stage applications. The output inductor is eliminated.  The magnetizing current is used to achieve ZVS for all switches. By choosing leakage inductance and output capacitance carefully, the turn-off current for the primary switch is very small and ZCS is achieved.  Most importantly, the body diode loss is eliminated.  A prototype is built to verify the theoretical analysis.  Its efficiency is as high as 96% at 1MHz switching frequency.  Compared with conventional PWM Buck, it can increase power density by 2.5 times.
Patent Information:
App Type Country Serial No. Patent No. File Date Issued Date Patent Status
US Continuation-in-Part *United States 11/094,434 7,254,047 3/31/2005 8/7/2007 Abandoned
For Information, Contact:
Li Chen
Licensing Associate
Virginia Tech Intellectual Properties, Inc.
(540) 443-9217
Yuancheng (frank) Ren
Julu Sun
Ming Xu
Fred Lee
Power Conversion/Control