scholarly journals Adaptive and Robust Operation with Active Fuzzy Harvester under Nonstationary and Random Disturbance Conditions

Sensors ◽  
2021 ◽  
Vol 21 (11) ◽  
pp. 3913
Author(s):  
Yushin Hara ◽  
Keisuke Otsuka ◽  
Kanjuro Makihara

The objective of this paper is to amplify the output voltage magnitude from a piezoelectric vibration energy harvester under nonstationary and broadband vibration conditions. Improving the transferred energy, which is converted from mechanical energy to electrical energy through a piezoelectric transducer, achieved a high output voltage and effective harvesting. A threshold-based switching strategy is used to improve the total transferred energy with consideration of the signs and amplitudes of the electromechanical conditions of the harvester. A time-invariant threshold cannot accomplish effective harvesting under nonstationary vibration conditions because the assessment criterion for desirable control changes in accordance with the disturbance scale. To solve this problem, we developed a switching strategy for the active harvester, namely, adaptive switching considering vibration suppression-threshold strategy. The strategy adopts a tuning algorithm for the time-varying threshold and implements appropriate intermittent switching without pre-tuning by means of the fuzzy control theory. We evaluated the proposed strategy under three realistic vibration conditions: a frequency sweep, a change in the number of dominant frequencies, and wideband frequency vibration. Experimental comparisons were conducted with existing strategies, which consider only the signs of the harvester electromechanical conditions. The results confirm that the presented strategy achieves a greater output voltage than the existing strategies under all nonstationary vibration conditions. The average amplification rate of output voltage for the proposed strategy is 203% compared with the output voltage by noncontrolled harvesting.

2008 ◽  
Vol 130 (4) ◽  
Author(s):  
Tsuyoshi Inoue ◽  
Yukio Ishida ◽  
Masaki Sumi

An electromagnetic actuator has the property to convert mechanical energy to electrical energy and vice versa. In this study, an electromagnetic resonant shunt damper, consisting of a voice coil motor with an electric resonant shunt circuit, is proposed. The optimal design of the shunt circuit is obtained theoretically for this electromagnetic resonant shunt damper. Furthermore, the effects of parameter errors of the elements of the electromagnetic resonant shunt damper are also investigated. The applicability of the theoretical findings for the proposed damper is justified by the experimental analysis.


Piezoelectric elements are commonly installed in shoe sole to make use of the piezoelectric effect due to the vibration generated by the human motion. Piezoelectric shoe is a great device that can be used to harvest energy and can be improved by adding more piezoelectric elements and providing storage to store the harvested energy. However, not many researchers focus on the analyzation of piezoelectric elements’ shape that may affect the efficiency of energy harvesting. In this paper, piezoelectric energy harvesting shoes are designed with piezoelectric elements installed inside the soles of the shoes, thereby gaining mechanical energy from user while walking and running. The mechanical energy was applied to the piezoelectric elements and converted into electrical energy. Bridge rectifier was used to convert the AC voltage output into DC voltage. The project focused on analyzation of the efficiency between round and square shaped piezoelectric elements. Different shape of the piezoelectric element produced different amount of output voltage. Square shaped piezoelectric tended to produce lesser output voltage than the round piezoelectric element. A round piezoelectric with diameter of 4.5cm produced mean output voltage up to 11.56V and square piezoelectric with size of 4.5cm x 4.5cm produced 6.12V. However, this all depended on how much pressure that was applied onto the piezoelectric elements.


Energies ◽  
2021 ◽  
Vol 14 (5) ◽  
pp. 1391
Author(s):  
Yeau-Ren Jeng ◽  
Andrew E. Mendy ◽  
Chi-Tse Ko ◽  
Shih-Feng Tseng ◽  
Chii-Rong Yang

A triboelectric generator (TEG) is a simple coupling combined with triboelectrification and electrostatic induction, which can convert mechanical energy into electrical energy and have the potential for self-powered device application. In this study, TEGs are fabricated consisting of a conductive textile (CT) layer (a fabric woven with polyester and stainless steel) and a polydimethylsiloxane (PDMS) layer. The CT friction layer is also used as a conductive electrode and designed with various surface morphologies, including unpatterned, dots, and lines with 1 and 2 cm spacings. Experimental results show that the TEG with an unpatterned CT layer produces an output voltage of 54.6 V and an output current of 5.46 µA. The patterned surfaces increase the effective contact area and friction effect between the CT and PDMS layers and hence enhance the output voltage and current to 94.4 V and 9.44 µA. Compared to the unpatterned CT layer, the pattern use of 1 cm spaced lines, 2 cm spaced lines, and dots improves the output voltage and current by 1.73, 1.68, and 1.24 times, respectively. Moreover, the TEG with 1 cm spaced lines generates a high output power density of 181.9 mW/m2.


2020 ◽  
Vol 64 (1-4) ◽  
pp. 729-736
Author(s):  
Jincheng He ◽  
Xing Tan ◽  
Wang Tao ◽  
Xinhai Wu ◽  
Huan He ◽  
...  

It is known that piezoelectric material shunted with external circuits can convert mechanical energy to electrical energy, which is so called piezoelectric shunt damping technology. In this paper, a piezoelectric stacks ring (PSR) is designed for vibration control of beams and rotor systems. A relative simple electromechanical model of an Euler Bernoulli beam supported by two piezoelectric stacks shunted with resonant RL circuits is established. The equation of motion of such simplified system has been derived using Hamilton’s principle. A more realistic FEA model is developed. The numerical analysis is carried out using COMSOL® and the simulation results show a significant reduction of vibration amplitude at the specific natural frequencies. Using finite element method, the influence of circuit parameters on lateral vibration control is discussed. A preliminary experiment of a prototype PSR verifies the PSR’s vibration reduction effect.


2021 ◽  
pp. 107754632110144
Author(s):  
Yiqing Yang ◽  
Haoyang Gao ◽  
Qiang Liu

Turning cutting tool with large length–diameter ratio has been essential when machining structural part with deep cavity and in-depth hole features. However, chatter vibration is apt to occur with the increase of tool overhang. A slender turning cutting tool with a length–diameter ratio of 7 is developed by using a vibration absorber equipped with piezoelectric ceramic. The vibration absorber has dual functions of vibration transfer to the absorber mass and vibration conversion to the electrical energy via the piezoelectric effect. Equations of motion are established considering the dual damping from the piezoelectric ceramic and rubber gasket. The equivalent damping of piezoelectric ceramic is derived, and the geometries are optimized to achieve optimal vibration suppression. The modal analysis demonstrates that the cutting tool with the vibration absorber can reach 80.1% magnitude reduction. Machining tests are carried out in the end. The machining acceleration and machined surface roughness validate the vibration suppression of the VA, and the output voltage by the piezoelectric ceramic demonstrates the ability of vibration sensing.


Author(s):  
Varij Panwar ◽  
Lokesh Singh Panwar ◽  
Gopinathan Anoop ◽  
Sukho Park

Author(s):  
Я.М. КАШИН ◽  
Л.Е. КОПЕЛЕВИЧ ◽  
А.В. САМОРОДОВ ◽  
Ч. ПЭН

Описаны конструктивные особенности трехвходовой аксиальной генераторной установки (ТАГУ), преобразующей кинетическую энергию ветра и световую энергию солнца и суммирующей механическую, световую и тепловую энергию с одновременным преобразованием полученной суммарной энергии в электрическую. Показаны преимущества ТАГУ перед двухвходовыми генераторными установками. Дополнительное включение стабилизатора напряжения в схему ТАГУ позволило расширить область применения стабилизированной трехвходовой аксиальной генераторной установки за счет стабилизации ее выходного напряжения. The design features of the three-input axial generating installation (TAGI), which converts the kinetic energy of wind and light energy of the sun and sums the mechanical, light and thermal energy with the simultaneous conversion of the total energy into electrical energy, are described. The benefits of TAGI in front of the two-input generating installation shown. The additional introduction of a voltage regulator into the TAGI scheme allowed to expand the scope of the stabilized three-input axial generating installation by stabilizing its output voltage.


2018 ◽  
Vol 7 (2-1) ◽  
pp. 433
Author(s):  
K. Sri Vamsi Krishna ◽  
Shiva Prasad ◽  
R. Sabari Vihar ◽  
K. Babitha ◽  
K Veeranjaneyulu ◽  
...  

The main objective of this study is to increase the aerodynamic efficiency of turbine mounted novel wing. The main motive behind this work is to reduce the drag by attaining the positive velocity gradient and generate power by converting the stagnation pressure which also acts as emergency power source. By using the energy source of free stream air, Mechanical energy is converted into electrical energy. The obtained power is presented in terms of voltage generated at various angles of attack with different Reynolds number. Experimental analysis is carried out for NACA4415 airfoil at various angles with respect to free stream ranging from 0deg to 30deg from laminar to turbulent Reynolds number. The results were obtained using the research tunnel at IARE aerodynamic facility center. The aerodynamic advantage of this design in terms of voltage is 9.5 V at 35m/s which can be utilized for the aircraft on board power systems.


2013 ◽  
Vol 28 (4) ◽  
pp. 1622-1631 ◽  
Author(s):  
Yi Zhao ◽  
Xin Xiang ◽  
Wuhua Li ◽  
Xiangning He ◽  
Changliang Xia

Sign in / Sign up

Export Citation Format

Share Document