An air insulated linear pulse transformer for electrodischarge technology

2021 ◽  
Vol 16 (12) ◽  
pp. P12006
Author(s):  
A.A. Zherlitsyn ◽  
V.M. Alexeenko ◽  
S.S. Kondratiev
Keyword(s):  
Output Pulse ◽  
Pulse Transformer ◽  
Wide Field ◽  
Matched Load ◽  
Charge Voltage ◽  
Mode Of Operation ◽  
In Series ◽  
Linear Pulse ◽  
A Charge ◽  
Transformer Output

Abstract A linear pulse transformer with air insulation at atmospheric pressure was created and tested under both constant resistance and non linear loads. The maximum power of the transformer output pulse reached ∼500 MW at a matched load with a charge voltage 50 kV. The transformer transferred ∼60% of the stored energy to the load over a characteristic time of about 1 μs. The scalability the generator was studied by connecting two identical transformers in series which gave a power output of ∼850 MW with doubled output voltage and reduced current. The frequency mode of operation was studied using one and two transformers with a charge voltage of 50 kV and a load that was, close to matched. In both cases, the power maximum and jitter showed no significant changes at any of the frequencies tested (up to 5 Hz). These results mean that the use of this generator can be recommended for a wide field of applications due to its scalability and low internal impedance.

scholarly journals A coaxial-output rolled strip pulse forming line based on multi-layer films

2018 ◽  
Vol 36 (1) ◽  
pp. 69-75 ◽  
Author(s):  
Jian-Cang Su ◽  
Rui Li ◽  
Jie Cheng ◽  
Bin-Xiong Yu ◽  
Xi-Bo Zhang ◽  
...  
Keyword(s):  
Rise Time ◽  
Axial Direction ◽  
Output Pulse ◽  
Rolled Strip ◽  
Strip Line ◽  
Matched Load ◽  
Multi Stage ◽  
Output Electrode ◽  
In Series ◽  
Discharging Characteristic

AbstractA coaxial-output rolled strip pulse-forming line (RSPFL) with a dry structure is researched for the purpose of miniaturization and all-solid state of pulse-forming lines (PFL). The coaxial-output RSPFL consists of a coaxial-output electrode (COE) and a rolled strip line (RSL). The COE is characterized by quasi-coaxial structure, making the output pulse propagate along the axial direction with a small output inductance. The RSL is rolled on the COE, whose transmission characteristics are analyzed theoretically. It shows that the RSL can be regarded as a planar strip line when the rolling radius of the strip line is larger than 60 times of the thickness of the insulation dielectric layer of RSL. CST modeling was carried out to simulate the discharging characteristic of the coaxial-output RSPFL. It shows that the coaxial-output RSPFL can deliver a discharging pulse with a rise time <6 ns when the impedance of the RSL matches that of the COE, which confirms the theoretical analysis. A prototype of the coaxial-output RSPFL was developed. A 49-kV discharging pulse on a matched load was achieved when it was charged to 100 kV. The discharging waveform has a pulse width of 32 ns, with a rise time of 6 ns, which is consistent with the simulation waveform. An energy-storage density of 1.9 J/L was realized in the coaxial-output RSPFL. By the method of multi-stage connection in series, a much higher output voltage is convenient to be obtained.

A gel-membrane model of glomerular charge and size selectivity in series

2001 ◽  
Vol 280 (3) ◽  
pp. F396-F405 ◽  
Author(s):  
Maria Ohlson ◽  
Jenny Sörensson ◽  
Börje Haraldsson
Keyword(s):  
Negative Charge ◽  
Careful Analysis ◽  
Size Selectivity ◽  
Gel Structure ◽  
Experimental Conditions ◽  
Ion Interactions ◽  
In Series ◽  
A Charge ◽  
Glomerular Barrier

We have analyzed glomerular sieving data from humans, rats in vivo, and from isolated perfused rat kidneys (IPK) and present a unifying hypothesis that seems to resolve most of the conflicting results that exist in the literature. Particularly important are the data obtained in the cooled IPK, because they allow a variety of experimental conditions for careful analysis of the glomerular barrier; conditions that never can be obtained in vivo. The data strongly support the classic concept of a negative charge barrier, but separate components seem to be responsible for charge and size selectivity. The new model is composed of a dynamic gel and a more static membrane layer. First, the charged gel structure close to the blood compartment has a charge density of 35–45 meq/l, reducing the concentration of albumin to 5–10% of that in plasma, due to ion-ion interactions. Second, the size-selective structure has numerous functional small pores (radius 45–50 Å) and far less frequent large pores (radius 75–115 Å), the latter accounting for 1% of the total hydraulic conductance. Both structures are required for the maintenance of an intact glomerular barrier.

scholarly journals SPICE Behaviors of Double Memristor Circuits Using Cosine Window Function

2021 ◽  
Vol 9 ◽  
Author(s):  
Kai-Da Xu ◽  
Donghao Li ◽  
Yannan Jiang ◽  
Qiang Chen
Keyword(s):  
Window Function ◽  
Charge Voltage ◽  
Hewlett Packard ◽  
Pspice Simulation ◽  
In Series ◽  
Linear And Nonlinear ◽  
High Flexibility ◽  
Flux Charge

In this paper, a Hewlett-Packard (HP) memristor model with a new window function and its versatile characteristics are presented. SPICE behaviors of the linear and nonlinear memristor model are studied through PSpice simulation. High flexibility is demonstrated for emulating the behaviors of the practical HP memristors. Furthermore, the characteristics of the composite SPICE behaviors are both investigated when two memristors are connected in series and in parallel. The polarity of each memristor is also taken into consideration. The relationships among flux, charge, voltage, current, and memristance of the double memristor circuits are simulated and analyzed.

PV-Battery Hybrid System with Less AH Capacity for Standalone DC Loads

2019 ◽  
Vol 20 (4) ◽  
Author(s):  
Vinay Kumar Kolakaluri ◽  
C. Vyjayanthi ◽  
Suresh Mikkili
Keyword(s):  
Hybrid System ◽  
Poor Performance ◽  
Partial Shading ◽  
Power Extraction ◽  
Pv Systems ◽  
Pv Array ◽  
Percentage Improvement ◽  
In Series ◽  
Average Current ◽  
A Charge

Abstract Partial Shading Condition (PSC) is one of the key issues faced by Solar Photovoltaic (PV) systems. PSCs mainly occur due to clouds, shadows of trees/buildings, dust and so on. During the PSC, the shaded PV module acts like a sink and absorbs the power from highest irradiated modules in a string and leads to hotspot. This situation is highly vulnerable and has to be avoided. Bypass diodes are used in series configured PV modules to overcome the hotspot effect caused due to PSC. However, the use of bypass diodes leads to multiple peaks in the Power-Voltage (P-V) graph of a PV array. One among them is Global peak point, where PV array needs to operate under PSC. In such a case, some amount of power generated by the shaded modules gets wasted, which will lead to poor performance and efficiency of the overall system. Moreover, for standalone DC load applications an auxiliary supply also required to provide reliable supply to the load during night times and PSC. Normally, batteries are used in standalone systems as an auxiliary supply. To control the charging and discharging process of battery a bi-directional DC-DC converter is used as a charge/discharge controller. The amount of power that is being charged/discharged by batteries depends upon the load requirement and solar power availability. Under PSC, due to lack of extraction of PV power from shaded modules, batteries have to supply the deficient power to the load. This situation forces to increase the AH capacity of the battery to provide reliable supply. In this research article PV-Battery Hybrid system is proposed to improve the performance of PV under varying irradiance and load conditions with reduced AH capacity of battery for standalone DC loads. The performance assessment of proposed topology has been carried out with the comparison of percentage improvement in power extraction, percentage reduction in the average current consumption of battery and SoC delivered by battery with conventional methodologies of bypass diode and proposed methodology under PSC. The assessment is carried out on MATLAB/SIMULINK and results are presented.

Defining the Tools: an Analysis of Laser Scanning Confocal and Wide-Field/Restoration Fluorescence Microscope Imaging

2001 ◽  
Vol 7 (S2) ◽  
pp. 1002-1003
Author(s):  
Jason R. Swedlow ◽  
Paul D. Andrews ◽  
Ke Hu ◽  
David S. RoosT ◽  
John M. Murray
Keyword(s):  
Fluorescence Imaging ◽  
Laser Scanning ◽  
Image Point ◽  
Fluorescence Signal ◽  
Wide Field ◽  
Charge Coupled Device ◽  
Standard Tool ◽  
Microscope Imaging ◽  
A Charge ◽  
Cellular Components

Digital fluorescence microscopy is now a standard tool for determining the localization of cellular components in fixed and living cells. Two fundamentally different imaging technologies are available for imaging fluorescently labelled cells and tissues, in either the fixed or living state. The laser scanning microscope uses a diffraction-limited focused beam to scan the sample and develop an image point by point. in addition, a pinhole placed in a plane confocal to the specimen prevents emitted out-of focus fluorescence from reaching the photomultiplier tube (PMT) detector. By combining spot illumination and selection of infocus fluorescence signal, the laser scanning confocal microscope (LSCM) creates an image of the specimen largely free of out-of-focus blur. By contrast, a wide-field microscope (WFM) illuminates the whole specimen simultaneously and detects the signal with a spatial array of point detectors, usually a charge-coupled device camera (CCD). This approach collects an image of all points of the specimen simultaneously and includes all the out-of-focus blurred light. Subsequent restoration by iterative deconvolution generates an estimate of the specimen, largely free of out-of-focus blur. While many other fluorescence imaging modalities exist, these two methods represent the majority of the fluorescence imaging systems currently in use in biomedical research.

Oscillatory Circuits Built on Physical SBT Memristor

2019 ◽  
Vol 29 (07) ◽  
pp. 1950097 ◽  
Author(s):  
Yuman Zhang ◽  
Mei Guo ◽  
Gang Dou ◽  
Yuxia Li ◽  
Guanrong Chen
Keyword(s):  
Complex Dynamics ◽  
Circuit Parameter ◽  
Chaotic Oscillations ◽  
Initial State ◽  
Oscillatory Circuit ◽  
Periodic Oscillations ◽  
Dynamical Behaviors ◽  
In Series ◽  
A Charge ◽  
Line Equilibrium

The [Formula: see text] (SBT) nanometer film can be used as a physical memristive component. Three oscillatory circuits built on the physical SBT memristor are proposed in this paper, one is self-excited oscillatory circuit and two are forced oscillatory circuits. These three oscillatory circuits have simple structures with complex dynamics. The self-excited oscillatory circuit can generate steady periodic oscillations; the first forced oscillatory circuit can generate relatively complex quasi-periodic oscillations, while the second can generate more complex dynamics such as chaotic oscillations. The impacts of the circuit parameter and initial state values of the SBT memristor on the dynamical behaviors of the three oscillatory circuits are investigated via numerical simulations. It is found that the SBT memristor can be used to design various memristor-based circuits. Specifically, in a flux-controlled memristor-based circuit, if an inductor is in parallel with the memristor, the order of the circuit is one less than the number of energy storage elements in the circuit. The equilibrium point of the circuit is different from the typical line equilibrium for autonomous circuits. The initial state value of the memristor has no impact on the steady state of the circuit. The same phenomena are observed for a charge-controlled memristor-based circuit, when a capacitor is in series with the memristor.

Submicrosecond linear pulse transformer for 800 kV voltage with modular low-inductance primary power supply

2016 ◽  
Vol 79 (14) ◽  
pp. 1590-1596
Author(s):  
Yu. A. Bykov ◽  
E. G. Krastelev ◽  
G. V. Popov ◽  
A. A. Sedin ◽  
V. F. Feduschak
Keyword(s):  
Power Supply ◽  
Pulse Transformer ◽  
Primary Power ◽  
Linear Pulse

scholarly journals Comparisons on Different Innovative Cascode GaN HEMT E-Mode Power Modules and Their Efficiencies on the Flyback Converter

Energies ◽  
2021 ◽  
Vol 14 (18) ◽  
pp. 5966
Author(s):  
Chih-Chiang Wu ◽  
Ching-Yao Liu ◽  
Sandeep Anand ◽  
Wei-Hua Chieng ◽  
Edward-Yi Chang ◽  
...  
Keyword(s):  
High Electron Mobility Transistors ◽  
Switching Frequency ◽  
High Electron ◽  
Flyback Converter ◽  
Gan Hemt ◽  
Electron Mobility Transistors ◽  
High Switching Frequency ◽  
In Series ◽  
Source Voltage ◽  
A Charge

The conventional cascode structure for driving depletion-mode (D-mode) gallium nitride (GaN) high electron mobility transistors (HEMTs) raises reliability concerns. This is because of the possibility of the gate to source voltage of the GaN HEMT surging to a negative voltage during the turn off transition. The existing solutions for this problem in the literature produce additional drawbacks such as reducing the switching frequency or introducing many additional components. These drawbacks may outweigh the advantages of using a GaN HEMT over its silicon (Si) alternative. This paper proposes two innovative gate drive circuits for D-mode GaN HEMTs—namely the GaN-switching based cascode GaN HEMT and the modified GaN-switching based cascode GaN HEMT. In these schemes, the Si MOSFET in series with the D-mode GaN HEMT is always turned on during regular operation. The GaN HEMT is then switched on and off by using a charge pump based circuit and a conventional gate driver. Since the GaN HEMT is driven independently, the highly negative gate-to-source voltage surge during turn off is avoided, and in addition, high switching frequency operation is made possible. Only two diodes and one capacitor are used in each of the schemes. The application of the proposed circuits is experimentally demonstrated in a high voltage flyback converter, where more than 96% efficiency is obtained for 60 W output load.

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