--- _id: '9541' abstract: - lang: eng text: Piezoelectric transformers are increasingly getting popular in the electrical devices owing to several advantages such as small size, high efficiency, no electromagnetic noise and non-flammable. In addition to the conventional applications such as ballast for back light inverter in notebook computers, camera flash, and fuel ignition several new applications have emerged such as AC/DC converter, battery charger and automobile lighting. These new applications demand high power density and wide range of voltage gain. Currently, the transformer power density is limited to $40 W/cm{^3}$ obtained at low voltage gain. The purpose of this study was to investigate a transformer design that has the potential of providing higher power density and wider range of voltage gain. The new transformer design utilizes radial mode both at the input and output port and has the unidirectional polarization in the ceramics. This design was found to provide 30 W power with an efficiency of 98\% and 30 $\,^{\circ}$C temperature rise from the room temperature. An electro-mechanical equivalent circuit model was developed to describe the characteristics of the piezoelectric transformer. The model was found to successfully predict the characteristics of the transformer. Excellent matching was found between the computed and experimental results. The results of this study will allow to deterministically design unipoled piezoelectric transformers with specified performance. It is expected that in near future the unipoled transformer will gain significant importance in various electrical components. author: - first_name: Tobias full_name: Hemsel, Tobias id: '210' last_name: Hemsel - first_name: S full_name: Priya, S last_name: Priya citation: ama: Hemsel T, Priya S. Model based analysis of piezoelectric transformers. Ultrasonics. 2006;44, Supplement(0):e741-e745. doi:10.1016/j.ultras.2006.05.086 apa: Hemsel, T., & Priya, S. (2006). Model based analysis of piezoelectric transformers. Ultrasonics, 44, Supplement(0), e741–e745. https://doi.org/10.1016/j.ultras.2006.05.086 bibtex: '@article{Hemsel_Priya_2006, title={Model based analysis of piezoelectric transformers}, volume={44, Supplement}, DOI={10.1016/j.ultras.2006.05.086}, number={0}, journal={Ultrasonics}, author={Hemsel, Tobias and Priya, S}, year={2006}, pages={e741–e745} }' chicago: 'Hemsel, Tobias, and S Priya. “Model Based Analysis of Piezoelectric Transformers.” Ultrasonics 44, Supplement, no. 0 (2006): e741–45. https://doi.org/10.1016/j.ultras.2006.05.086.' ieee: T. Hemsel and S. Priya, “Model based analysis of piezoelectric transformers,” Ultrasonics, vol. 44, Supplement, no. 0, pp. e741–e745, 2006. mla: Hemsel, Tobias, and S. Priya. “Model Based Analysis of Piezoelectric Transformers.” Ultrasonics, vol. 44, Supplement, no. 0, 2006, pp. e741–45, doi:10.1016/j.ultras.2006.05.086. short: T. Hemsel, S. Priya, Ultrasonics 44, Supplement (2006) e741–e745. date_created: 2019-04-29T09:22:21Z date_updated: 2022-01-06T07:04:16Z department: - _id: '151' doi: 10.1016/j.ultras.2006.05.086 issue: '0' keyword: - Piezoelectric transformers language: - iso: eng page: e741 - e745 publication: Ultrasonics publication_identifier: issn: - 0041-624X quality_controlled: '1' status: public title: Model based analysis of piezoelectric transformers type: journal_article user_id: '55222' volume: 44, Supplement year: '2006' ... --- _id: '8926' abstract: - lang: eng text: Piezoelectric transformers are well known since the publication of some patent applications at the end of the 1950s. But until today their only business use lies in the field of backlighting systems for LCDs. Due to key features as light-weight, flatness, high step-up at low volume and high efficiency piezoelectric transformers should be usable in a much broader range of applications. This contribution returns to mind their operating principle, shows how to model and to develop such devices as well as give some aspects for development trends that will lead to further applications. author: - first_name: Tobias full_name: Hemsel, Tobias id: '210' last_name: Hemsel - first_name: Walter full_name: Littmann, Walter last_name: Littmann - first_name: Jörg full_name: Wallaschek, Jörg last_name: Wallaschek citation: ama: 'Hemsel T, Littmann W, Wallaschek J. Piezoelectric transformers - state of the art and development trends. In: Ultrasonics Symposium, 2002. Proceedings. 2002 IEEE. Vol 1. ; 2002:645-648. doi:10.1109/ULTSYM.2002.1193485' apa: Hemsel, T., Littmann, W., & Wallaschek, J. (2002). Piezoelectric transformers - state of the art and development trends. In Ultrasonics Symposium, 2002. Proceedings. 2002 IEEE (Vol. 1, pp. 645–648). https://doi.org/10.1109/ULTSYM.2002.1193485 bibtex: '@inproceedings{Hemsel_Littmann_Wallaschek_2002, title={Piezoelectric transformers - state of the art and development trends}, volume={1}, DOI={10.1109/ULTSYM.2002.1193485}, number={vol.1}, booktitle={Ultrasonics Symposium, 2002. Proceedings. 2002 IEEE}, author={Hemsel, Tobias and Littmann, Walter and Wallaschek, Jörg}, year={2002}, pages={645–648} }' chicago: Hemsel, Tobias, Walter Littmann, and Jörg Wallaschek. “Piezoelectric Transformers - State of the Art and Development Trends.” In Ultrasonics Symposium, 2002. Proceedings. 2002 IEEE, 1:645–48, 2002. https://doi.org/10.1109/ULTSYM.2002.1193485. ieee: T. Hemsel, W. Littmann, and J. Wallaschek, “Piezoelectric transformers - state of the art and development trends,” in Ultrasonics Symposium, 2002. Proceedings. 2002 IEEE, 2002, vol. 1, no. vol.1, pp. 645–648. mla: Hemsel, Tobias, et al. “Piezoelectric Transformers - State of the Art and Development Trends.” Ultrasonics Symposium, 2002. Proceedings. 2002 IEEE, vol. 1, no. vol.1, 2002, pp. 645–48, doi:10.1109/ULTSYM.2002.1193485. short: 'T. Hemsel, W. Littmann, J. Wallaschek, in: Ultrasonics Symposium, 2002. Proceedings. 2002 IEEE, 2002, pp. 645–648.' date_created: 2019-04-15T10:18:15Z date_updated: 2022-01-06T07:04:05Z department: - _id: '151' doi: 10.1109/ULTSYM.2002.1193485 intvolume: ' 1' issue: vol.1 keyword: - piezoelectric devices - reviews - transformers - backlighting systems - flatness - high efficiency piezoelectric transformers - high step-up - light-weight - low volume - operating principle - piezoelectric transformers - Circuits - Costs - Electromagnetic devices - Electromagnetic fields - Mechanical energy - Piezoelectric materials - Power electronics - Switching frequency - Transformers - Vibrations language: - iso: eng page: 645-648 publication: Ultrasonics Symposium, 2002. Proceedings. 2002 IEEE publication_identifier: issn: - 1051-0117 status: public title: Piezoelectric transformers - state of the art and development trends type: conference user_id: '55222' volume: 1 year: '2002' ...