New coupled-inductor SEPIC converter with very high conversion ratio and reduced voltage stress on the switches

The new circuit of the coupled-inductor SEPIC converter is proposed. By addition of the secondary output inductor and diode in a basic SEPIC converter a new converter with a large conversion ratio is obtained. The splitting of this secondary inductor into two windings reduces the voltage stresses on the main switch and diodes. The additional diode helps to circulate the leakage inductance energy to the load in a non-oscillatory manner. The transistor turns on/off with soft-switching. The voltage stress on both the transistor and diodes is less than the output voltage. Computer simulation and experimental results confirmed the theoretical expectations.

[1]  Adrian Ioinovici,et al.  Step-up DC power supply based on a switched-capacitor circuit , 1995, IEEE Trans. Ind. Electron..

[2]  João Batista Vieira,et al.  A quadratic buck converter with lossless commutation , 2000, IEEE Trans. Ind. Electron..

[3]  Fred C. Lee,et al.  A front-end DC/DC converter for network server applications , 2001, 2001 IEEE 32nd Annual Power Electronics Specialists Conference (IEEE Cat. No.01CH37230).

[4]  Tae-Jin Kim,et al.  High boost converter using voltage multiplier , 2005, 31st Annual Conference of IEEE Industrial Electronics Society, 2005. IECON 2005..

[5]  Rong-Jong Wai,et al.  High step-up converter with coupled-inductor , 2005, IEEE Transactions on Power Electronics.

[6]  Rong-Jong Wai,et al.  High step-up converter with coupled-inductor , 2005 .

[7]  Y. Berkovich,et al.  Switched Coupled-Inductor Cell for DC-DC Converters with Very Large Conversion Ratio , 2011, IECON 2006 - 32nd Annual Conference on IEEE Industrial Electronics.

[8]  N. Vazquez,et al.  The Tapped-Inductor Boost Converter , 2007, 2007 IEEE International Symposium on Industrial Electronics.

[9]  Adrian Ioinovici,et al.  Switched-Capacitor/Switched-Inductor Structures for Getting Transformerless Hybrid DC–DC PWM Converters , 2008, IEEE Transactions on Circuits and Systems I: Regular Papers.

[10]  Y. Berkovich,et al.  Improved circuit of the switched coupled-inductor cell for dc-dc converters with very large conversion ratio , 2009, 2009 13th European Conference on Power Electronics and Applications.