Quantum mode control for piezoelectric transformers in AC/DC applications

Piezoelectric transformers (PTs) could be an attractive solution to reduce size and weight in AC/DC adapters for portable terminals. In these topologies, the magnetic transformers limit the converter miniaturization and are also EMI sources. Piezoelectric transformers feature low profile high power density and low EMI generation. In this paper, a new control method ("Quantum") for PT-based converters is introduced. As a result, an 8-Watt AC/DC adapter (110 V/sub AC/ input, 12 V/sub DC/ output) is also presented operating at frequencies around 500 kHz with quantum mode control.

[1]  Fernando Nuño García,et al.  A new control strategy for an AC/DC converter based on a piezoelectric transformer , 2004, IEEE Transactions on Industrial Electronics.

[2]  Tamotsu Ninomiya,et al.  New piezoelectric transformer converter for AC-adapter , 1997, Proceedings of APEC 97 - Applied Power Electronics Conference.

[3]  F. Nuno,et al.  A very simple DC/DC converter using piezoelectric transformer , 2001, 2001 IEEE 32nd Annual Power Electronics Specialists Conference (IEEE Cat. No.01CH37230).

[4]  C. A. Rosen.  Ceramic transformers and filters , 1957 .

[5]  M. Shoyama,et al.  Piezoelectric transformer converter with frequency control , 1995, Proceedings of INTELEC 95. 17th International Telecommunications Energy Conference.

[6]  F. Nuno,et al.  A new control strategy for an AC/DC converter based on a piezoelectric transformer , 2001, APEC 2001. Sixteenth Annual IEEE Applied Power Electronics Conference and Exposition (Cat. No.01CH37181).

[7]  T. Ninomiya,et al.  Piezoelectric transformer converter with PWM control , 1996, Proceedings of Applied Power Electronics Conference. APEC '96.

[8]  J.A. Cobos,et al.  Miniaturised battery charger using piezoelectric transformers , 2001, APEC 2001. Sixteenth Annual IEEE Applied Power Electronics Conference and Exposition (Cat. No.01CH37181).