Efficiency Improvement of Synchronous Buck Converter by Passive Auxiliary Circuit

This paper proposes a zero-voltage-transition (ZVT) pulsewidth-modulated (PWM) synchronous buck converter, which is designed to operate at low voltage and high efficiency typically required for portable systems. A new passive auxiliary circuit that allows the main switch to operate with zero-voltage switching has been incorporated in the conventional PWM synchronous buck converter. The operation principles and detailed steady-state analysis of the ZVT PWM synchronous converter with a passive auxiliary circuit are presented. All of the semiconductor devices aside from the main switch operate under soft-switching conditions. Thus, the auxiliary circuit provides a larger overall efficiency. The feasibility of the auxiliary circuit is confirmed by the simulation and experimental results.

[1]  G. Joos,et al.  Analysis of a zero voltage transition boost converter using a soft switching auxiliary circuit with reduced conduction losses , 2001, 2001 IEEE 32nd Annual Power Electronics Specialists Conference (IEEE Cat. No.01CH37230).

[2]  K. M. Smith,et al.  Properties and synthesis of passive lossless soft-switching PWM converters , 1999 .

[3]  Humberto Pinheiro,et al.  Unified design for ZVT PWM converters with resonant auxiliary circuit , 2004 .

[4]  K. Fujiwara,et al.  A novel lossless passive snubber for soft-switching boost-type converters , 1999 .

[5]  Helio Leaes Hey,et al.  Zero-voltage transition PWM converters: a classification methodology , 2005 .

[6]  Chern-Lin Chen,et al.  Novel ZVT-PWM converters with active snubbers , 1998 .

[7]  M. Brkovic,et al.  High frequency synchronous buck converter for low voltage applications , 1998, PESC 98 Record. 29th Annual IEEE Power Electronics Specialists Conference (Cat. No.98CH36196).

[8]  Adrian Ioinovici,et al.  A family of zero-voltage and zero-current-switching (ZVZCS) three-level DC-DC converters with secondary-assisted regenerative passive snubber , 2005, IEEE Transactions on Circuits and Systems I: Regular Papers.

[9]  A. Elasser,et al.  Soft switching active snubbers for dc/ac converters , 1995 .

[10]  Fred C. Lee,et al.  Novel zero-current-transition PWM converters , 1993 .

[11]  K. M. Smith,et al.  A comparison of voltage-mode soft-switching methods for PWM converters , 1997 .

[12]  C.M.T. Cruz,et al.  A family of turn-on and turn-off nondissipative passive snubbers for soft-switching single-phase rectifier with reduced conduction losses , 2004, 2004 IEEE 35th Annual Power Electronics Specialists Conference (IEEE Cat. No.04CH37551).