scholarly journals Analysis and Numerical Evaluation of H∞ and H2 Optimal Design Schemes for an Electromagnetic Shunt Damper

2019 ◽  
Vol 142 (2) ◽  
Author(s):  
Wai Kei Ao ◽  
Paul Reynolds
Keyword(s):  
Optimal Design ◽  
Coupling Effect ◽  
Dynamic Properties ◽  
Electromagnetic Coupling ◽  
Optimization Technique ◽  
Engineering Structures ◽  
Electromagnetic Damping ◽  
Circuit Components ◽  
Resonant Shunt ◽  
Shunt Circuit

Abstract The electromagnetic coupling effect can generate electromagnetic damping to suppress disturbance, which can be utilized for vibration serviceability control in civil engineering structures. An electrodynamic actuator is used as a passive electromagnetic damper (EMD). Ideally, the EMD is assumed to be attached between the ground and the structure. The kinetic energy of the vibrating structure can be converted to electrical energy to activate the electromagnetic damping. To induce appropriate damping, the two terminals of the damper need to be closed and cascaded with a resonant shunt circuit as an electromagnetic shunt damper (EMSD). In this study, an resistance–inductance–capacitance (RLC) oscillating circuit is chosen. For determination of optimal circuit components and comparing against the tuned mass damper (TMD), existing H∞ design formulae are applied. This work extends this with a detailed development of an H2 robust optimization technique. The dynamic properties of a footbridge structure are then selected and used to verify the EMSD optimal design numerically. The vibration suppression performance is analytically equivalent to the dynamic characteristic of the TMD and has feasible installation and better damping enhancement. To further evaluate the potential application of the EMSD, multi-vibration mode manipulation via connecting multiple RLC resonant shunt circuits is adopted. The multiple RLC shunt circuit connecting to EMD is an alternative to the single mode control of a traditional TMD. Therefore, the EMSD can, in principle, effectively achieve suppression of single and multiple vibration modes.

Vibration Suppression Using Electromagnetic Resonant Shunt Damper

2008 ◽  
Vol 130 (4) ◽  
Author(s):  
Tsuyoshi Inoue ◽  
Yukio Ishida ◽  
Masaki Sumi
Keyword(s):  
Optimal Design ◽  
Experimental Analysis ◽  
Vibration Suppression ◽  
Mechanical Energy ◽  
Voice Coil Motor ◽  
Electrical Energy ◽  
Electromagnetic Actuator ◽  
Resonant Shunt ◽  
Shunt Circuit

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.

Guidelines for the layout and tuning of piezoelectric resonant shunt with negative capacitances in terms of dynamic compliance, mobility and accelerance

2021 ◽  
pp. 1045389X2098699
Author(s):  
Marta Berardengo ◽  
Stefano Manzoni ◽  
Olivier Thomas ◽  
Marcello Vanali
Keyword(s):  
Dynamic Compliance ◽  
Practical Implementation ◽  
Experimental Campaign ◽  
Vibration Attenuation ◽  
Circuit Components ◽  
Resonant Shunt ◽  
Theoretical Results ◽  
Shunt Impedance ◽  
Piezoelectric Shunt ◽  
Shunt Circuit

This paper addresses the vibration attenuation provided by the resonant piezoelectric shunt enhanced by means of negative capacitances. The shunt impedance is composed by one or two negative capacitances, a resistance and an inductance. It is shown that closed analytical formulations, common to all the possible connections of the negative capacitances, can be derived for the tuning of the circuit components and for the prediction of the attenuation in terms of dynamic compliance, mobility and accelerance. The paper also compares the attenuation performance provided by the two possible layouts for the electrical link between the resistance and the inductance, that are series and parallel. Furthermore, this work evidences which shunt configurations offer advantages in terms of practical implementation and the benefits provided by the use of negative capacitances in the shunt circuit. In the last part of the paper, guidelines for the use of resonant shunt are given to the reader and, finally, the theoretical results are validated by means of an experimental campaign showing that it is possible to cancel the resonance on which the resonant shunt is targeted.

An hourglass-type electromagnetic isolator with negative resistance electromagnetic shunt circuit

2020 ◽  
Vol 64 (1-4) ◽  
pp. 549-556
Author(s):  
Yajun Luo ◽  
Linwei Ji ◽  
Yahong Zhang ◽  
Minglong Xu ◽  
Xinong Zhang
Keyword(s):  
Vibration Isolation ◽  
Electromechanical Coupling ◽  
Coupling Effect ◽  
Negative Resistance ◽  
Isolation System ◽  
Amplitude Vibration ◽  
Vibration Responses ◽  
The Stability ◽  
Isolation Performance ◽  
Shunt Circuit

The present work proposed an hourglass-type electromagnetic isolator with negative resistance (NR) shunt circuit to achieve the effective suppression of the micro-amplitude vibration response in various advanced instruments and equipment. By innovatively design of combining the displacement amplifier and the NR electromagnetic shunt circuit, the current new type of vibration isolator not only can effectively solve the problem of micro-amplitude vibration control, but also has significant electromechanical coupling effect, to obtain excellent vibration isolation performance. The design of the isolator and motion relationship is presented firstly. The electromechanical coupling dynamic model of the isolator is also given. Moreover, the optimal design of the NR electromagnetic shunt circuit and the stability analysis of the vibration isolation system are carried out. Finally, the simulation results about the transfer function and vibration responses demonstrated that the isolator has a significant isolation performance.

Optimal design of Large Mode Area All-Solid-Fiber Using a Gray Relational Optimization Technique

Optik ◽  
2021 ◽  
pp. 167188
Author(s):  
She Yu-lai ◽  
Zhang Wen-tao ◽  
Liang Guoling ◽  
Tang yuan ◽  
Tu Shan
Keyword(s):  
Optimal Design ◽  
Optimization Technique ◽  
Large Mode Area ◽  
Mode Area

scholarly journals Duty-Cycled Wireless Power Transmission for Millimeter-Sized Biomedical Implants

Electronics ◽  
2020 ◽  
Vol 9 (12) ◽  
pp. 2130
Author(s):  
Muhammad Abrar Akram ◽  
Kai-Wen Yang ◽  
Sohmyung Ha
Keyword(s):  
Duty Cycle ◽  
Power Transmission ◽  
Electromagnetic Coupling ◽  
System Level ◽  
Cmos Process ◽  
Biomedical Implants ◽  
Wireless Power ◽  
Wireless Power Transmission ◽  
Short Period ◽  
Circuit Components

Wireless power transmission (WPT) using an inductively coupled link is one of the most popular approaches to deliver power wirelessly to biomedical implants. As the electromagnetic wave travels through the tissue, it is attenuated and absorbed by the tissue, resulting in much weaker electromagnetic coupling than in the air. As a result, the received input power on the implant is very weak, and so is the input voltage at the rectifier, which is the first block that receives the power on the implant. With such a small voltage amplitude, the rectifier inevitably has a very poor power conversion efficiency (PCE), leading to a poor power transfer efficiency (PTE) of the overall WPT system. To address this challenge, we propose a new system-level WPT method based on duty cycling of the power transmission for millimeter-scale implants. In the proposed method, the power transmitter (TX) transmits the wave with a duty cycle. It transmits only during a short period of time and pauses for a while instead of transmitting the wave continuously. In doing so, the TX power during the active period can be increased while preserving the average TX power and the specific absorption rate (SAR). Then, the incoming voltage becomes significantly larger at the rectifier, so the rectifier can rectify the input with a higher PCE, leading to improved PTE. To investigate the design challenges and applicability of the proposed duty-cycled WPT method, a case for powering a 1 × 1-mm2-sized neural implant through the skull is constructed. The implant, a TX, and the associated environment are modeled in High-Frequency Structure Simulator (HFSS), and the circuit simulations are conducted in Cadence with circuit components in a 180-nm CMOS process. At a load resistor of 100 kΩ, an output capacitor of 4 nF, and a carrier frequency of 144 MHz, the rectifier’s DC output voltage and PCE are increased by 300% (from 1.5 V to 6 V) and by 50% (from 14% to 64%), respectively, when the duty cycle ratio of the proposed duty-cycled power transmission is varied from 100% to 5%.

Sign in / Sign up

Export Citation Format

Share Document