Fabrication of high-power piezoelectric transformers using lead-free ceramics for application in electronic ballasts

Song-Ling Yang; Shih-Ming Chen; Cheng-Che Tsai; Cheng-Shong Hong; Sheng-Yuan Chu

doi:10.1109/TUFFC.2013.2577

Fabrication of high-power piezoelectric transformers using lead-free ceramics for application in electronic ballasts

IEEE Trans Ultrason Ferroelectr Freq Control. 2013 Feb;60(2):408-13. doi: 10.1109/TUFFC.2013.2577.

Authors

Song-Ling Yang¹, Shih-Ming Chen, Cheng-Che Tsai, Cheng-Shong Hong, Sheng-Yuan Chu

Affiliation

¹ Department of Electrical Engineering, National Cheng Kung University, Tainan, Taiwan, ROC.

PMID: 23357915
DOI: 10.1109/TUFFC.2013.2577

Abstract

CuO is doped into (Na(0.5)K(0.5))NbO(3) (NKN) ceramics to improve the piezoelectric properties and thus obtain a piezoelectric transformer (PT) with high output power. In X-ray diffraction patterns, the diffraction angles of the CuO-doped NKN ceramics shift to lower values because of an expansion of the lattice volume, thus inducing oxygen vacancies and enhancing the mechanical quality factor. A homogeneous microstructure is obtained when NKN is subjected to CuO doping, leading to improved electrical properties. PTs with different electrode areas are fabricated using the CuO-doped NKN ceramics. Considering the efficiency, voltage gain, and temperature rise of PTs at a load resistance of 1 kΩ, PTs with an electrode with an inner diameter of 15 mm are combined with the circuit design for driving a 13-W T5 fluorescent lamp. A temperature rise of 6°C and a total efficiency of 82.4% (PT and circuit) are obtained using the present PTs.