Simulation analysis of equivalent circuit model of skin-electrode impedance for transcutaneous electrical stimulation

For more than 50 years, transcutaneous electrical stimulation method has been used to cure the spinal cord injury, stroke or cerebral palsy. This method works by activating the excitable nerves, muscle fibers by electrical current stimulation through electrode to skin interface. Electrode to skin interface requires equivalent circuit to overcome the inability of measuring the skin resistivity directly. We have learned several previous models, which are from Lawler, Moineau and Keller and Kuhn. Unfortunately, Moineau model neglects the capacitance effect, while Lawler and Keller and Kuhn include capacitive and resistive nature of skin in their equivalent circuits. Both models consisted of only one parallel RC block. Therefore, this paper presents the simulation results of the proposed equivalent circuit model using two parallel RC circuits. Simulation of the proposed model is conducted in MATLAB 2015a and compared with two previous models using certain parameters. Results show that the proposed model obtained the impedance of 10.830 kΩ when it is simulated using 100Hz frequency, for Lawler model the impedance is 5.340 kΩ and Keller and Kuhn model the impedance obtained is 6.490 kΩ. The proposed model has the refined impedance compared with other models and is expected to deliver better electrical stimulation.

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Equivalent circuit model of eddy current damping regarding frequency-dependence with test validation

Advances in Structural Engineering ◽

10.1177/13694332211050989 ◽

2021 ◽

pp. 136943322110509

Author(s):

Zhiguo Shi ◽

Cheng Ning Loong ◽

Jiazeng Shan

Keyword(s):

Equivalent Circuit ◽

Eddy Current ◽

Dynamic Testing ◽

Equivalent Circuit Model ◽

Time History ◽

Circuit Model ◽

Theoretical Expression ◽

Fe Model ◽

Damping Force ◽

Proposed Model

This study proposes an equivalent circuit model to simulate the mechanical behavior and frequency-dependent characteristic of eddy current (EC) damping, with the validations from multi-physics finite element (FE) modeling and dynamic testing. The equivalent circuit model is first presented with a theoretical expression of the EC damping force. Then, the transient analysis with an ANSYS-based FE model of an EC damper is performed. The time-history forces from the FE model are compared with that from the proposed equivalent circuit model. The favorable agreement indicates that the proposed model can simulate the nonlinear behavior of EC damping under different excitation scenarios. A noncontact and friction-free planar EC damper is designed, and its dynamic behavior is measured by employing shake table testing. The experimental observations can be reproduced by the proposed equivalent circuit model with reasonable accuracy and reliability. The proposed equivalent circuit model is compared with the classical viscous model and the higher-order fractional model using a complex EC damper simulated in ANSYS to show the advantages of the proposed model regarding model simplicity and prediction accuracy. A single-degree-of-freedom (SDOF) structure with different EC damping models is further analyzed to illustrate the need for accurate EC damping modeling.

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Equivalent circuit model of Ge/Si separate absorption charge multiplication avalanche photodiode

Modern Physics Letters B ◽

10.1142/s0217984917503584 ◽

2018 ◽

Vol 32 (08) ◽

pp. 1750358

Author(s):

Wei Wang ◽

Ting Chen ◽

Linshu Yan ◽

Xiaoyuan Bao ◽

Yuanyuan Xu ◽

...

Keyword(s):

Equivalent Circuit ◽

Equivalent Circuit Model ◽

Avalanche Photodiode ◽

Circuit Model ◽

Uniform Electric Field ◽

Rate Equations ◽

Current Frequency ◽

Proposed Model ◽

Parasitic Effect ◽

Field Noise

The equivalent circuit model of Ge/Si Separate Absorption Charge Multiplication Avalanche Photodiode (SACM-APD) is proposed. Starting from the carrier rate equations in different regions of device and considering the influences of non-uniform electric field, noise, parasitic effect and some other factors, the equivalent circuit model of SACM-APD device is established, in which the steady-state and transient current voltage characteristics can be described exactly. In addition, the proposed Ge/Si SACM APD equivalent circuit model is embedded in PSpice simulator. The important characteristics of Ge/Si SACM APD such as dark current, frequency response, shot noise are simulated, the simulation results show that the simulation with the proposed model are in good agreement with the experimental results.

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A nonlinear equivalent circuit model for flux density calculation of a permanent magnet linear synchronous motor

Serbian Journal of Electrical Engineering ◽

10.2298/sjee1503359g ◽

2015 ◽

Vol 12 (3) ◽

pp. 359-373

Author(s):

Reza Ghanaee ◽

Ahmad Darabi ◽

Arash Kioumarsi ◽

Mohammad Baghayipour ◽

Mohammad Morshed

Keyword(s):

Permanent Magnet ◽

Equivalent Circuit ◽

Analytical Method ◽

Equivalent Circuit Model ◽

Synchronous Motor ◽

Circuit Model ◽

Magnetic Equivalent Circuit ◽

Linear Synchronous Motor ◽

Proposed Model ◽

Simulation Results

In this paper, a nonlinear magnetic equivalent circuit is presented as an analytical solution method for modeling of a permanent magnet linear synchronous motor (PMLSM). The accuracy of the proposed model is verified via comparing its simulation results with those obtained by two other methods. These two are the Maxwell?s Equations based analytical method and the wellknown finite elements method (FEM). Saturation and any saliency e.g. slotting effects can be considered properly by both nonlinear magnetic equivalent circuit and FEM, where it cannot be taken into account easily by the Maxwell?s Equations based analytical approach. Accordingly, as the simulation results presented in this paper confirm, the proposed nonlinear magnetic equivalent circuit is compatible with FEM regarding the accuracy while it requires very shorter execution time. Therefore, the magnetic equivalent circuit model of the present paper can be considered as a preferable substitute for the time consuming FEM and approximated analytical method built on Maxwell?s Equations in particular when required to be applied for a design optimization problem.

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Novel Equivalent Circuit Model for Spiral Inductors on Lossy Silicon Substrate

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.300-301.1003 ◽

2013 ◽

Vol 300-301 ◽

pp. 1003-1007

Author(s):

Juan Zou ◽

Zhe Nan Tang

Keyword(s):

Equivalent Circuit ◽

Silicon Substrate ◽

Equivalent Circuit Model ◽

Magnetic Coupling ◽

Cmos Technology ◽

Circuit Model ◽

Lateral Resistance ◽

Proposed Model ◽

Spiral Inductors ◽

Numerical Formulation

Abstract. A fast and accurate equivalent circuit model for spiral inductors on lossy silicon substrate is presented and the parameters of the model are extracted without applying any fitting and optimized methods. In this model, the lateral resistance and inductance of substrate are introduced to model the eddy-current losses induced by magnetic coupling between the spiral and the substrate. FastHenry method is used to extract the inductances of spiral, substrate, and the mutual inductance between them. A numerical formulation is used to efficiently capture the proximity and skin effects in metal tracks. The proposed model is used to predict the performance of two typical spiral inductors fabricated in CMOS technology. The model shows excellent accuracy and efficiency by the comparison with measure results at the frequency from 100MHz to 10GHz.

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Equivalent Circuit Model for Electric Double Layer Capacitors and its Applications

IEEJ Transactions on Power and Energy ◽

10.1541/ieejpes.131.524 ◽

2011 ◽

Vol 131 (6) ◽

pp. 524-529

Author(s):

Susumu Yamashiro ◽

Koichi Nakamura

Keyword(s):

Equivalent Circuit ◽

Double Layer ◽

Electric Double Layer ◽

Equivalent Circuit Model ◽

Circuit Model ◽

Double Layer Capacitors ◽

Electric Double Layer Capacitors

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An Equivalent Circuit Model for Vertical Comb Drive MEMS Optical Scanner Controlled by Pulse Width Modulation

IEEJ Transactions on Sensors and Micromachines ◽

10.1541/ieejsmas.132.1 ◽

2012 ◽

Vol 132 (1) ◽

pp. 1-9 ◽

Cited By ~ 7

Author(s):

Satoshi Maruyama ◽

Muneki Nakada ◽

Makoto Mita ◽

Takuya Takahashi ◽

Hiroyuki Fujita ◽

...

Keyword(s):

Equivalent Circuit ◽

Pulse Width ◽

Pulse Width Modulation ◽

Equivalent Circuit Model ◽

Circuit Model ◽

Comb Drive ◽

Optical Scanner

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A Novel, Improved Equivalent Circuit Model for Double-Sided Linear Induction Motor

Electronics ◽

10.3390/electronics10141644 ◽

2021 ◽

Vol 10 (14) ◽

pp. 1644

Author(s):

Qian Zhang ◽

Huijuan Liu ◽

Tengfei Song ◽

Zhenyang Zhang

Keyword(s):

Finite Element ◽

Finite Element Model ◽

Equivalent Circuit ◽

Skin Effect ◽

Equivalent Circuit Model ◽

Element Model ◽

Circuit Model ◽

End Effects ◽

3D Finite Element ◽

Linear Induction

A novel, improved equivalent circuit model of double-sided linear induction motors (DLIMs) is proposed, which takes the skin effect and the nonzero leakage reactance of the secondary, longitudinal, and transverse end effects into consideration. Firstly, the traditional equivalent circuit with longitudinal and transverse end effects are briefly reviewed. Additionally, the correction coefficients for longitudinal and transverse end effects derived by one-dimensional analysis models are given. Secondly, correction factors for skin effect, which reflects the inhomogeneous air gap magnetic field vertically, and the secondary leakage reactance are derived by the quasi-two-dimensional analysis model. Then, the proposed equivalent circuit is presented, and the excitation reactance and secondary resistance are modified by the correction coefficients derived from the three analytical models. Finally, a three-dimensional (3D) finite element model is used to verify the proposed equivalent circuit model under varying air gap width and frequency, and the results are also compared with that of the traditional equivalent circuit models. The calculated thrust characteristics by the proposed equivalent circuit and 3D finite element model are experimentally validated under a constant voltage–frequency drive.

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