This paper presents the application of the Pareto-based multicriteria optimization technique to problems of increasing the efficiency of piezoelectric generators(PEGs).The optimization problem was solved for two types...This paper presents the application of the Pareto-based multicriteria optimization technique to problems of increasing the efficiency of piezoelectric generators(PEGs).The optimization problem was solved for two types of generators:cantilever and stack.For the cantilever generator,the task was to optimize the design in such a way as to obtain the maximum output power for a given mechanical excitation.The optimization process was divided into several stages,which significantly reduced the amount of calculations.The task of optimizing the stack type for a given form of mechanical loading consisted in finding the geometric parameters of the generator at which the output voltage and power would be maximum.In the result of solving both problems,sets of geometric design parameters of PEGs were obtained,on the basis of which efficient transducers can be developed for specific operating conditions.It turned out that this technique is more suitable for optimizing the design of cantilever generators than for stack ones in given constraints.The solution of both problems was realized using the finite element method.展开更多
Based on the variational principle,equations and boundary conditions for transverse steady vibrations of a bimorph consisting of a piezoelectric and piezomagnetic layers are obtained.The results of calculations of nat...Based on the variational principle,equations and boundary conditions for transverse steady vibrations of a bimorph consisting of a piezoelectric and piezomagnetic layers are obtained.The results of calculations of natural frequencies are compared with the finite element model of the device in ACELAN.展开更多
It has been established that in plates made of hot-pressed ferroelectric ceramics PZT-19(Tc=300℃),after metal electrodes from Ag are burned into opposite surfaces with different depths of mechanical damage,counter-di...It has been established that in plates made of hot-pressed ferroelectric ceramics PZT-19(Tc=300℃),after metal electrodes from Ag are burned into opposite surfaces with different depths of mechanical damage,counter-directional stationary deformation gradients and,accordingly,internal electric displacement fields create a stationary flexoelectric effect.As a result,unpolarized ceramics below the Curie temperature become a pyroelectric,and above it become a pyroelectric bolometer.After polishing the less damaged surface and replacing the Ag(valency v=3)electrode with Cr(v=6)by thermal evaporation in vacuum from the intact surface,a new thermally stable polarization is created,directed from the damaged surface in the interelectrode volume.Such plates have an asymmetric dielectric hysteresis loop,retain the values of the pyroelectric effect and piezoelectric effect in the ferroelectric phase,as well as the bolometric effect in the paraelectric phase after repeated heating cycles to 400℃ and cooling to T_(norm).展开更多
基金The reported study was funded by RFBR according to the research projects Nos.18-38-00912 mol a,19-08-00365 and by Russian Academy of Science(project A16-116012610052-3).
文摘This paper presents the application of the Pareto-based multicriteria optimization technique to problems of increasing the efficiency of piezoelectric generators(PEGs).The optimization problem was solved for two types of generators:cantilever and stack.For the cantilever generator,the task was to optimize the design in such a way as to obtain the maximum output power for a given mechanical excitation.The optimization process was divided into several stages,which significantly reduced the amount of calculations.The task of optimizing the stack type for a given form of mechanical loading consisted in finding the geometric parameters of the generator at which the output voltage and power would be maximum.In the result of solving both problems,sets of geometric design parameters of PEGs were obtained,on the basis of which efficient transducers can be developed for specific operating conditions.It turned out that this technique is more suitable for optimizing the design of cantilever generators than for stack ones in given constraints.The solution of both problems was realized using the finite element method.
基金The last author is grateful for the support of the Ministry of Science and Higher Education of the Russian Federation,Project No.9.1001.2017/4.6 for modelling,and contract No.075-15-2019-1928 for computer calculation.
文摘Based on the variational principle,equations and boundary conditions for transverse steady vibrations of a bimorph consisting of a piezoelectric and piezomagnetic layers are obtained.The results of calculations of natural frequencies are compared with the finite element model of the device in ACELAN.
基金This research was performed into framework of financing RFBR grant number 19-08-00365A.
文摘It has been established that in plates made of hot-pressed ferroelectric ceramics PZT-19(Tc=300℃),after metal electrodes from Ag are burned into opposite surfaces with different depths of mechanical damage,counter-directional stationary deformation gradients and,accordingly,internal electric displacement fields create a stationary flexoelectric effect.As a result,unpolarized ceramics below the Curie temperature become a pyroelectric,and above it become a pyroelectric bolometer.After polishing the less damaged surface and replacing the Ag(valency v=3)electrode with Cr(v=6)by thermal evaporation in vacuum from the intact surface,a new thermally stable polarization is created,directed from the damaged surface in the interelectrode volume.Such plates have an asymmetric dielectric hysteresis loop,retain the values of the pyroelectric effect and piezoelectric effect in the ferroelectric phase,as well as the bolometric effect in the paraelectric phase after repeated heating cycles to 400℃ and cooling to T_(norm).
