World Academy of Science, Engineering and Technology
Published October 21, 2010 | Version 5540
Journal article Open

Coreless Printed Circuit Board (PCB) Stepdown Transformers for DC-DC Converter Applications

Description

In this paper, multilayered coreless printed circuit board (PCB) step-down power transformers for DC-DC converter applications have been designed, manufactured and evaluated. A set of two different circular spiral step-down transformers were fabricated in the four layered PCB. These transformers have been modelled with the assistance of high frequency equivalent circuit and characterized with both sinusoidal and square wave excitation. This paper provides the comparative results of these two different transformers in terms of their resistances, self, leakage, mutual inductances, coupling coefficient and also their energy efficiencies. The operating regions for optimal performance of these transformers for power transfer applications are determined. These transformers were tested for the output power levels of about 30 Watts within the input voltage range of 12-50 Vrms. The energy efficiency for these step down transformers is observed to be in the range of 90%-97% in MHz frequency region.

Files

5540.pdf

Files (416.5 kB)

Name Size
md5:f21a5e2e024ed2bd17bc61e6f9ebf02d
416.5 kB Preview Download

Additional details

References

  • Conor Quinn, Karl Rinne, Terence O-Donnell, Maeve Duffy and Cian O Mathuna, "A review of Planar Magnetic Techniques and Technologies--, IEEE APEC 2001, pp.1175-1183.
  • Colonel William, T.McLyman, "Transformer and Inductor design Handbook--CRC press; 3 edition.
  • Wong, Fu Keung, "High Frequency transformers for switch mode power supplies--, Griffith University, 2004.
  • S.C.Tang, S.Y.R .Hui and H. Chung, "Coreless Printed Circuit Board (PCB) Transformers -Fundamental characteristics and application potential", IEEE Circuits and Systems Newsletter, Vol. 11, No. 3, Third Quarter 2000, p.1, pp.3-15 and p.47.
  • C.F.Coombs, "Printed Circuits handbooks" 5th Edition, McGraw-Hill, August 27, 2001.
  • S.C.Tang, S.Y. (Ron) Hui and Henry Shu-Hung Chung, "Characterization of Coreless Printed Circuit Board (PCB) Transformers", IEEE Transactions on Power Electronics, Vol. 15, No. 6, November 2000,pp.1275-1282.
  • Alex Van den Bossche and Vencislav Cekov Valchev, "Inductors and Transformers for Power Electronics"1st Edition, CRC Press, March24, 2005.
  • Sun-Min Hwang and Tae-Young Ahn, "A ZVS forward DC-DC Converter Using Coreless PCB Transformer and Inductor", 2001.
  • Heng-Ming Hsu, "Effective series-resistance model of spiral inductors", Microwave and Optical technology letters, vol.46, No.2, July 20, 2005. pp.107-109 [10] Robert W .Erickson, "Fundamentals of Power Electronics"2nd Edition, Springer International Edition, pp.505. [11] S.C.Tang, S.Y.(Ron)Hui and Henry Shu-Hung Chung, "Coreless planar Printed-Circuit-Board (PCB) Transformers-A Fundamental Concept for Signal and Energy Transfer", IEEE Transactions on Power Electronics, vol 15, No.5, September 2000, pp.931-941. [12] JAMES H.SPREEN, "Electrical Terminal Representation of Conductor Loss in Transformers", IEEE Transactions on Power Electronics, vol 5, No.4, October 1990.