Parameters and design optimization of the ring piezoelectric ceramic transformer

Abstract

Main aim of the presented paper is the theoretical analysis and experimental verification of the transformation parameters for the new type of nonhomogeneously poled ring transformer. The input part is poled in the thickness direction and output part in the radial direction. Two transformer geometries are studied -the input part is at inner ring segment, or it is at the outer ring segment. The optimum electrode size aspect ratios have been found experimentally as d 1 =D % 0:60 À 0:65 for the ring with aspect ratio d=D ¼ 0:2. The fundamental as well as higher overtone resonances were studied for the transformation ratio, the optimum resistive load, efficiency and no-load transformation ratio. Higher overtones have better transformation parameters compared to the fundamental resonance. The new type ring transformer exhibits very high transformation ratios up to 200 under no-load and up to 13.4 under a high efficiency of 97% at the optimum load conditions of 10 k. Strong electric field gradient at the output circuit is applicable for the electrical discharge generation.

Forced Electro-Elastic Vibrations of the Piezoceramic Plates and Rods With Divided Electrodes. Part I: Analytical Relations for Coupling Coefficients and Admittance’s Components

“…Ав-тори вважають таку конструкцію кільцевим тран-сформатором типу Розена, основною перевагою якого перед класичним пластинковим варіантом є більша вихідна потужність. Така сама кільцева структура досліджена і в [28] для двох випадків, коли вихідний електрод розміщений на зовніш-ньому або внутрішньому ободі кільця. Показано, що вищі обертони мають кращі параметри, ніж основна радіальна мода.…”

“…Аналітичні й експериментальні дослідження [25,28,30] для поперечно поляризованих стри-жнів показали, що максимум динамічного КЕМЗ на основному поздовжньому резонансі досяга-ється, коли електродне покриття займає 75% площі пластини. Перший радіальний резонанс досягає максимальної ефективності, коли внутрі-шнє електродне покриття займає 80% діаметра пластини [31,32].…”

Modeling and experimental verification of the thin multi-electrode piezoceramic bars' forced vibrations

“…Piezoelectric bars with transversal polarization became already a "touchstone" in many experimental researches because their vibrations are described by simple mathematical formulae, and the first overtone lies far on frequency from fundamental resonance [6][7][8][9][10][11][12][13][14][15]. The mechanical and electric values of these structures are coupled between itself by so-called the transversal coefficient of electromechanical coupling (EMCF) k 31 and this is a reason why the longitudinal vibrations of such bars are known as k 31 mode [1][2][3]18].…”

“…However, sometimes it is not possible to impose a full electrode on the piezoelectric resonator faces due to the mechanical clamping or electrical insulation of the resonator. Small facet on the piezoelectric ceramic ring or disc edges is one of the examples of such electrode deposition deficiency [11][12][13]. There is also possibility of EMCF enhancement by the divided electrode pattern optimization [14][15][16][17].…”

Analysis and measurement of high frequency piezoelectric ring resonator

“…12) In contrast, there has been a surge of research into piezoelectric ring resonators with tunable frequencies, where the fundamental frequency depends on the size of the ring region. 13,14) Ambati's early work laid the groundwork by introducing a comprehensive formulation for analyzing these vibrations in hollow ring plates, extending this study to solid disks and thin rings by varying the size of the central opening. 15) Iula et al further contributed to the understanding of ring resonators by defining the material coupling factor for the ring geometry, considering its variation concerning the inner-to-outer radius ratio.…”