scholarly journals Validation of a SPICE Model for High Frequency Electroporation Systems

Electronics ◽  
2019 ◽  
Vol 8 (6) ◽  
pp. 710
Author(s):  
Paulius Butkus ◽  
Sonata Tolvaišienė ◽  
Sebastjanas Kurčevskis

In this paper, we present an analysis and a validation of a simulation program with integrated circuit emphasis (SPICE) model for a pulse forming circuit of a high frequency electroporation system, which can deliver square-wave sub-microsecond (100–900 ns) electric field pulses. The developed SPICE model is suggested for use in evaluation of transient processes that occur due to high frequency operations in prototype systems. A controlled crowbar circuit was implemented to support a variety of biological loads and to ensure a constant electric pulse rise and fall time during electroporation to be independent of the applied buffer bioimpedance. The SPICE model was validated via a comparison of the simulation and experimental results obtained from the already existing prototype system. The SPICE model results were in good agreement with the experimental results, and the model complexity was found to be sufficient for analysis of transient processes. As result, the proposed SPICE model can be useful for evaluation and compensation of transient processes in sub-microsecond pulsed power set-ups during the development of new prototypes.

1998 ◽  
Vol 21 (4) ◽  
pp. 279-292 ◽  
Author(s):  
A. Haddi ◽  
A. Maouad ◽  
O. Elmazria ◽  
A. Hoffmann ◽  
J. P. Charles

A simplified IGBT (Insulated Gate Bipolar Transistor) SPICE macromodel, based on its equivalent circuit, is proposed. This macromodel is provided to simulate various mechanisms governing the behavior of the IGBT, and it takes into account specific phenomena limiting its SOA (Safe Operating Area), such as forward and reverse biased SOA, as well as latch-up. The validity of this model is confirmed by comparison between simulation and experimental results as well as the data sheets. This comparison is tested for two IGBT devices showing two different powers and switching speeds, and a good agreement is recorded for both IGBT devices.


2012 ◽  
Vol 466-467 ◽  
pp. 607-611
Author(s):  
Xiao Guang Yang

A new model is proposed for analyzing the capacitive effects in a newly developed high frequency coaxial transformer (HFCT). The proposed model can describe both the electric energy storage and common-mode (CM) electromagnetic interference (EMI) noise behaviors of a transformer, considering the voltage distribution in the HFCT windings. To determine the parameters of the model, a parasitic capacitance network is developed to describe the HFCT’s real winding’s structure, and the distributed parasitic capacitances of the network are evaluated using FEM based on the theory of capacitances in a multi-conductor system. The calculated inter-capacitance of the HFCT is in good agreement with the experimental results.


2019 ◽  
Vol 22 (2) ◽  
pp. 88-93
Author(s):  
Hamed Khanger Mina ◽  
Waleed K. Al-Ashtrai

This paper studies the effect of contact areas on the transient response of mechanical structures. Precisely, it investigates replacing the ordinary beam of a structure by two beams of half the thickness, which are joined by bolts. The response of these beams is controlled by adjusting the tightening of the connecting bolts and hence changing the magnitude of the induced frictional force between the two beams which affect the beams damping capacity. A cantilever of two beams joined together by bolts has been investigated numerically and experimentally. The numerical analysis was performed using ANSYS-Workbench version 17.2. A good agreement between the numerical and experimental results has been obtained. In general, results showed that the two beams vibrate independently when the bolts were loosed and the structure stiffness is about 20 N/m and the damping ratio is about 0.008. With increasing the bolts tightening, the stiffness and the damping ratio of the structure were also increased till they reach their maximum values when the tightening force equals to 8330 N, where the structure now has stiffness equals to 88 N/m and the damping ratio is about 0.062. Beyond this force value, increasing the bolts tightening has no effect on stiffness of the structure while the damping ratio is decreased until it returned to 0.008 when the bolts tightening becomes immense and the beams behave as one beam of double thickness.


1996 ◽  
Vol 05 (04) ◽  
pp. 653-670 ◽  
Author(s):  
CÉLINE FIORINI ◽  
JEAN-MICHEL NUNZI ◽  
FABRICE CHARRA ◽  
IFOR D.W. SAMUEL ◽  
JOSEPH ZYSS

An original poling method using purely optical means and based on a dual-frequency interference process is presented. We show that the coherent superposition of two beams at fundamental and second-harmonic frequencies results in a polar field with an irreducible rotational spectrum containing both a vector and an octupolar component. This enables the method to be applied even to molecules without a permanent dipole such as octupolar molecules. After a theoretical analysis of the process, we describe different experiments aiming at light-induced noncentrosymmetry performed respectively on one-dimensional Disperse Red 1 and octupolar Ethyl Violet molecules. Macroscopic octupolar patterning of the induced order is demonstrated in both transient and permanent regimes. Experimental results show good agreement with theory.


2021 ◽  
Vol 11 (10) ◽  
pp. 4631
Author(s):  
Yu Chen ◽  
Xiaoqing Ji ◽  
Zhongyong Zhao

The accurate establishment of the equivalent circuit model of the synchronous machine windings’ broadband characteristics is the basis for the study of high-frequency machine problems, such as winding fault diagnosis and electromagnetic interference prediction. Therefore, this paper proposes a modeling method for synchronous machine winding based on broadband characteristics. Firstly, the single-phase high-frequency lumped parameter circuit model of synchronous machine winding is introduced, then the broadband characteristics of the port are analyzed by using the state space model, and then the equivalent circuit parameters are identified by using an optimization algorithm combined with the measured broadband impedance characteristics of port. Finally, experimental verification and comparison experiments are carried out on a 5-kW synchronous machine. The experimental results show that the proposed modeling method identifies the impedance curve of the circuit parameters with a high degree of agreement with the measured impedance curve, which indicates that the modeling method is feasible. In addition, the comparative experimental results show that, compared with the engineering exploratory calculation method, the proposed parameter identification method has stronger adaptability to the measured data and a certain robustness. Compared with the black box model, the parameters of the proposed model have a certain physical meaning, and the agreement with the actual impedance characteristic curve is higher than that of the black box model.


2021 ◽  
Vol 5 (3) ◽  
pp. 32
Author(s):  
Benedikt Mutsch ◽  
Peter Walzel ◽  
Christian J. Kähler

The droplet deformation in dispersing units of high-pressure homogenizers (HPH) is examined experimentally and numerically. Due to the small size of common homogenizer nozzles, the visual analysis of the transient droplet generation is usually not possible. Therefore, a scaled setup was used. The droplet deformation was determined quantitatively by using a shadow imaging technique. It is shown that the influence of transient stresses on the droplets caused by laminar extensional flow upstream the orifice is highly relevant for the droplet breakup behind the nozzle. Classical approaches based on an equilibrium assumption on the other side are not adequate to explain the observed droplet distributions. Based on the experimental results, a relationship from the literature with numerical simulations adopting different models are used to determine the transient droplet deformation during transition through orifices. It is shown that numerical and experimental results are in fairly good agreement at limited settings. It can be concluded that a scaled apparatus is well suited to estimate the transient droplet formation up to the outlet of the orifice.


Energies ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 187 ◽  
Author(s):  
Kamil Bargieł ◽  
Damian Bisewski ◽  
Janusz Zarębski

The paper deals with the problem of modelling and analyzing the dynamic properties of a Junction Field Effect Transistor (JFET) made of silicon carbide. An examination of the usefulness of the built-in JFET Simulation Program with Integrated Circuit Emphasis (SPICE) model was performed. A modified model of silicon carbide JFET was proposed to increase modelling accuracy. An evaluation of the accuracy of the modified model was performed by comparison of the measured and calculated capacitance–voltage characteristics as well as the switching characteristics of JFETs.


2020 ◽  
Vol 12 (4) ◽  
pp. 676 ◽  
Author(s):  
Yong Yang ◽  
Wei Tu ◽  
Shuying Huang ◽  
Hangyuan Lu

Pansharpening is the process of fusing a low-resolution multispectral (LRMS) image with a high-resolution panchromatic (PAN) image. In the process of pansharpening, the LRMS image is often directly upsampled by a scale of 4, which may result in the loss of high-frequency details in the fused high-resolution multispectral (HRMS) image. To solve this problem, we put forward a novel progressive cascade deep residual network (PCDRN) with two residual subnetworks for pansharpening. The network adjusts the size of an MS image to the size of a PAN image twice and gradually fuses the LRMS image with the PAN image in a coarse-to-fine manner. To prevent an overly-smooth phenomenon and achieve high-quality fusion results, a multitask loss function is defined to train our network. Furthermore, to eliminate checkerboard artifacts in the fusion results, we employ a resize-convolution approach instead of transposed convolution for upsampling LRMS images. Experimental results on the Pléiades and WorldView-3 datasets prove that PCDRN exhibits superior performance compared to other popular pansharpening methods in terms of quantitative and visual assessments.


Sign in / Sign up

Export Citation Format

Share Document