A lead-free piezoelectric transformer in radial vibration modes

Guo, M., Lin, D.M., Lam, K.H. , Wang, S., Chan, H. L.W. and Zhao, X.Z. (2007) A lead-free piezoelectric transformer in radial vibration modes. Review of Scientific Instruments, 78(3), 035102. (doi: 10.1063/1.2712795) (PMID:17411212)

Abstract

In this study, a disk-shaped piezoelectric transformer was fabricated using lead-free (K, Na)Nbo3-based ceramics with high mechanical quality factor. The transformer can operate in the fundamental or the third radial vibration mode. The transformer is poled along the thickness direction. The top surface is covered by ring/dot silver electrodes separated by an annular gap which serve as the input and output parts of the transformer, respectively. The bottom surface, fully covered with a silver electrode, is grounded as a common electrode. The dimensions of the top ring/dot electrodes are designed such that the third radial vibration mode can be strongly excited. The electrical properties of the transformer with diameter of 34.2mm and thickness of 1.9mm were measured. For a temperature rise of 35°C⁠, the transformer has a maximum output power of 12W⁠. With the matching load, its maximum efficiency is >95%⁠, and maximum voltage gains are 6.5 and 3.9 for the fundamental and the third radial vibration modes, respectively. It has potential to be used in power supply units and other electronic circuits.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Lam, Dr Koko
• Authors: Guo, M., Lin, D.M., Lam, K.H., Wang, S., Chan, H. L.W., and Zhao, X.Z.
• College/School: College of Science and Engineering > School of Engineering > Systems Power and Energy
• Journal Name: Review of Scientific Instruments
• Publisher: American Institute of Physics
• ISSN: 0034-6748
• ISSN (Online): 1089-7623