Статті в журналах: "Pulse current generator"

1

Kandratsyeu, Aleh, Uladzimir Sabaleuski, Luis Redondo, and Andrei G. Pakhomov. "Four Channel 6.5 kV, 65 A, 100 ns–100 µs Generator with Advanced Control of Pulse and Burst Protocols for Biomedical and Biotechnological Applications." Applied Sciences 11, no. 24 (December 11, 2021): 11782. http://dx.doi.org/10.3390/app112411782.

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Pulsed electric fields in the sub-microsecond range are being increasingly used in biomedical and biotechnology applications, where the demand for high-voltage and high-frequency pulse generators with enhanced performance and pulse flexibility is pushing the limits of pulse power solid state technology. In the scope of this article, a new pulsed generator, which includes four independent MOSFET based Marx modulators, operating individually or combined, controlled from a computer user interface, is described. The generator is capable of applying different pulse shapes, from unipolar to bipolar pulses into biological loads, in symmetric and asymmetric modes, with voltages up to 6.5 kV and currents up to 65 A, in pulse widths from 100 ns to 100 µs, including short-circuit protection, current and voltage monitoring. This new scientific tool can open new research possibility due to the flexibility it provides in pulse generation, particularly in adjusting pulse width, polarity, and amplitude from pulse-to-pulse. It also permits operating in burst mode up to 5 MHz in four independent channels, for example in the application of synchronized asymmetric bipolar pulses, which is shown together with other characteristics of the generator.

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2

Godun, D. V., S. V. Bordusau, and G. P. Budzko. "Output Current Control System of a High Voltage Electric Pulse Generator for Plasma Excitation." PLASMA PHYSICS AND TECHNOLOGY 6, no. 1 (2019): 7–9. http://dx.doi.org/10.14311/ppt.2019.1.7.

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A control and pulse discharge current limiting system integrated into an AC/DC converter and pulse modulator of a high voltage pulse generator have been developed. The peculiarity of such system\textquotesingle s operation is the stabilization of the power supplied to the discharge and the correction of the width of output electric pulses towards decrease upon reaching the specified pulsed current amplitude value. The system enables the pulse generator to work in the modes close to the ``short circuited load'' mode. In this case the driving module of a composite IGBT key performs the correction of the working pulse width and blocks the pulse generator operation if needed. The suggested circuit design solutions allow using the generator in a wide range of electric plasma-forming parameters' modes and working with various types of vacuum gas discharge systems.

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3

Dang, Khanh Quoc, Makoto Nanko, Masakazu Kawahara, and Shinichi Takei. "Densification of Alumina Powder by Using PECS Process with Different Pulse Electric Current Waveforms." Materials Science Forum 620-622 (April 2009): 101–4. http://dx.doi.org/10.4028/www.scientific.net/msf.620-622.101.

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Densification and sample temperature of alumina (Al2O3) powder during pulsed electric current sintering with different pulse power generators, inverter type and pulsed direct current type were investigated. The sample temperature for inverter generator was higher than that for pulsed direct current generator in same die temperature ranging form 800 to 1400oC. The relative density increased with increasing of the sample temperature.

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4

Muthuramalingam, T., B. Mohan, and D. Saravanakumar. "Evaluation of Surface Finish of Electrical Discharge Machined AISI 304 Stainless Steel with Various Pulse Generators." Applied Mechanics and Materials 772 (July 2015): 279–83. http://dx.doi.org/10.4028/www.scientific.net/amm.772.279.

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The performance improvement in Electrical Discharge Machining process is a tedious one in materials and manufacturing processes especially in making of complex die and moulds. Due to non linear nature of this process, conventional pulse generators such as RC pulse generator and transistor pulse train generator cannot produce uniform energy distribution. Since RC pulse generator can produce smaller crater volume, it can make better surface finish than transistor pulse train generator crater size is influenced by the discharge current produced during the machining process. Due to its stochastic behavior, the discharge current is varied for every spark. The modified iso current pulse generator can produce uniform energy distribution with smaller crater size. In this study, EDM drilling experiments have been conducted on AISI 304 stainless steel with the RC pulse generator, Transistor pulse generator and iso energy pulse generator in electrical erosion process. The effects of these pulse generators on surface characterization have been evaluated and analyzed. From the evaluation results, it has been detected that the iso energy pulse generator has produced better surface structure than conventional pulse generators.

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5

Gromov, Victor, Vladimir Kuznetsov, Sergey Konovalov, Goui Tang, Gou Lin Song, Kseniya Alsaraeva, and Alexander Semin. "Estimation of Current Amplitude Pulse." Advanced Materials Research 1013 (October 2014): 166–69. http://dx.doi.org/10.4028/www.scientific.net/amr.1013.166.

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Method of estimation of current amplitude (~10 kA) pulses constructed by powerful current pulse generator is suggested. It bases on the solution of differential equation current and voltage change on capacitor. The final formula consists of maximum value of capacitor charge, maximum negative voltage value, pulse duration and capacitor value.

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6

Song, Falun, Fei Li, Beizhen Zhang, Mingdong Zhu, Chunxia Li, Ganping Wang, Haitao Gong, Yanqing Gan, and Xiao Jin. "Recent advances in compact repetitive high-power Marx generators." Laser and Particle Beams 37, no. 01 (March 2019): 110–21. http://dx.doi.org/10.1017/s0263034619000272.

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AbstractThis paper introduces recent activities on Marx-based compact repetitive pulsed power generators at the Institute of Applied Electronics (IAE), China Academy of Engineering Physics (CAEP), over the period 2010–2018. A characteristic feature of the generators described is the use of a simplified bipolar charged Marx circuit, in which the normal isolation resistors or inductors to ground are removed to make the circuit simpler. Several pulse-forming modules developed to generate a 100 ns square wave output are introduced, including thin-film dielectric lines of different structures, a pulse-forming line based on a Printed Circuit Board, and non-uniform pulse-forming networks. A compact repetitive three-electrode spark gap switch with low-jitter, high-voltage, and high-current was developed and is used in the generators. A positive and negative series resonant constant current power supply with high precision and high power is introduced. As an important part of the repetitive pulse power generator, a lower jitter pulse trigger source is introduced. Several typical high-power repetitive pulsed power generators developed at IAE are introduced including a 30 GW low-impedance Marx generator, a compact square-wave pulse generator based on Kapton-film dielectric Blumlein line, a 20 GW high pulse-energy repetitive PFN-Marx generator, and a coaxial Marx generator based on ceramic capacitors. The research of key technologies and their development status are discussed, which can provide a reference for the future development and application of miniaturization of compact and repetitive Marx generators.

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7

Flaxer, E. "High-voltage pulse modulated radio frequency generator for dielectric barrier discharge combined with ultra-fast high power pulse generator." Journal of Instrumentation 16, no. 10 (October 1, 2021): P10003. http://dx.doi.org/10.1088/1748-0221/16/10/p10003.

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Abstract Dielectric barrier discharge is the electrical discharge between two electrodes separated by an insulating dielectric barrier. The discharge process typically uses a high-voltage alternating current in the range of several kilohertz to several gigahertz. A high-frequency and high-power pulse generator is required to drive the discharge process through the capacitance load. There are two main techniques to implement this type of generator: the forced and resonant modes. This work demonstrates the implementation of a programmable digital circuit based on a digital signal controller and a full H-bridge that combines the two topologies and can be used as a controller for dielectric barrier discharge with varying capacitance and structure. We integrated an ultra-fast, high-resolution, and high-power pulse generator into a radio frequency generator to drive high-pressure, supersonic, pulsed valves. The excitation based on our DBD and the combined generator produces cold plasma beams. The controller generates discharge voltages of up to 5 kV, in pulses of 10 to 50 μs wide, at rates of up to 1 kHz, while the discharge frequency ranges are from 1 to 3 MHz under a capacitive load of 100 pF. The power generator applies a current pulse of up to 20 A and voltage of up to 150 V.

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8

Kuznetsov, V. A., G. D. Polkovnikov, V. E. Gromov, V. A. Kuznetsova, and O. A. Peregudov. "High power current pulse generator based on reversible thyristor converter." Izvestiya. Ferrous Metallurgy 62, no. 12 (January 15, 2020): 964–71. http://dx.doi.org/10.17073/0368-0797-2019-12-964-971.

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In metal forming using high power current pulses, it becomes necessary to control both reproduction frequency and pulse amplitude. Description of a generator of high power current pulses with controlled thyristor converter is provided as a power source of charging device (charger) for regulating voltage (pulse amplitude) of capacitor charge. Faults of the generators associated with inrush current in capacitor charge modes are revealed, which reduces quality of supply network. To reduce time of transient processes while lowering voltage across capacitors, application of reverse thyristor converter is applied as a power source. Structural diagram of generator is considered, which includes reversible thyristor converter with separate control, power unit, capacitor recharge device, charger parameters automatic control system and capacitor charge process control system. Calculation of parameters of automatic control system regulators is presented. To obtain optimal transients, standard methodology for setting regulators to a modular optimum was used. In order to reduce overshoot at time of disturbances appearance, which can reach 100 % and higher, socalled logical device was introduced into the automatic control system. It blocks control pulses on thyristors of converter and simultaneously reduces signal at the output of current regulator to zero. Simulation model of high power current pulse generator in MatLab – Simulink environment was synthesized. Analysis of the model was carried out, and graphs are given that explain principle of device operation and transition processes under various operating modes. Generator application will allow user to adjust amplitude of current pulses with high speed and to obtain sufficiently high-quality transient processes of capacitors charge (discharge), which will have beneficial effect on supply network. Application of better converters will significantly increase frequency of reproduction of current pulses.

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9

Liu, Sheng, Jian-Cang Su, Xibo Zhang, Ya-Feng Pan, Hong-Yan Fan, and Xu-Liang Fan. "A Tesla-type long-pulse generator with wide flat-top width based on a double-width pulse-forming line." Laser and Particle Beams 36, no. 1 (March 2018): 115–20. http://dx.doi.org/10.1017/s0263034618000034.

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AbstractTo produce pulses with good flat-top quality, pulse-forming lines (PFLs) have been widely used in the field of Tesla-type pulse generators. To shorten the physical length of the PFL, a double-width PFL (DWPFL) is proposed that doubles the output pulse width while maintaining flat-top quality. A repetitively 10 GW Tesla-type long-pulse generator producing pulses with flat-top width of about 110 ns was developed with a coaxial DWPFL to produce high-current electron beams. Electron beams of about 10 GW with flat-top widths of about 110 ns were obtained on a planar vacuum diode load. With this pulse generator and a C-band high-power microwave system, microwaves of ~2.2 GW power and full-width at half-maximum of 101 ns were generated. The experiment demonstrates the feasibility and ideal output waveform quality of the DWPFL.

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10

Xi, H., C. Liang, F. Q. Zhang, M. J. Li, and T. P. Peng. "A pulse current generator for dense plasma focus." Journal of Instrumentation 16, no. 12 (December 1, 2021): P12021. http://dx.doi.org/10.1088/1748-0221/16/12/p12021.

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Abstract A pulse current generator applied in a type of high-yield intense pulsed neutron source, the Dense Plasma Focus (DPF), is designed and developed in this paper. There are three key components in this generator. Each group of capacitors and switches is integrative to meet the DPF's requirements of low circuit inductance. A coaxial multi-channel switch is developed to solve the problems of the switch inductance, the jitter and the electrode erosion. A kind of sectorial plate transmission line is adopted to transfer the high pulse current from the capacitors to the DPF. The following technical parameters of the generator were achieved on dummy load: output current amplitude of ∼560 kA when primary capacitors are charged with 22 kV.

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11

Kondratenko, I. P., A. N. Karlov, and R. S. Kryshchuk. "CONTROL STRATEGIES TO ELIMINATE HARMONICS IN POWER GENERATION SYSTEMS BASED ON A DOUBLY-FED INDUCTION GENERATOR." Praci Institutu elektrodinamiki Nacionalanoi akademii nauk Ukraini, no. 61 (May 25, 2022): 5–12. http://dx.doi.org/10.15407/publishing2022.61.005.

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The action of high-density pulsed currents (109 A/m2) leads to the appearance of the electro-plastic effect in metal products. It is proposed to use magnetic pulse treatment of nonmagnetic plates by electromagnetic inductors with a U-shaped magnetic circuit for local flow pulsed currents in the nonmagnetic plates. The work aims to establish an influence of a ferromagnetic platform with nonlinear magnetic permeability on pulsed eddy currents and magnetic pressure of nonmagnetic metal plates with different electrical conductivity in modeling magnetic pulse treatment of welded joints to achieve the electro-plastic effect. Numerical simulation of pulsed electromagnetic fields by the finite element method is used. The current calculation in the inductor's winding is performed by solving the equations of the magnetic field and the electric circuit equations for a discrete-time interval. A power source is a capacitor that is charged to a specific voltage. To study the effect of the ferromagnetic platform on eddy currents and forces in a nonmagnetic plate with its different electrical conductivity, the same pulsed current in the inductor's winding is used. The dependence of amplitude values of eddy current density and magnetic pressure on the surfaces of nonmagnetic plates of different electrical conductivity is investigated. The influence of the presence and absence of a ferromagnetic platform and its electrical conductivity and magnetic permeability on the values of eddy currents and magnetic pressure in the nonmagnetic plate have been studied. Ref. 13, fig. 7, table.

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12

Lü, Ze-Qi, Yan-Zhao Xie, Ming-Yue Gou, Xiao-Yu Chen, Jin-Shan Zhou, Mei Li, and Yi Zhou. "Development of 200 kV multi-function pulsed radiation system." Acta Physica Sinica 70, no. 20 (2021): 205206. http://dx.doi.org/10.7498/aps.70.20210583.

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<sec>A multi-functional pulsed radiation system with a peak voltage of 200 kV, an impedance of 2 Ω, and a full width at half maximum (FWHM) of 30 ns is developed. The system can be switched flexibly in two states of generating pulsed electron beam and pulsed X-ray by changing the cathode and anode. It consists of a pulse power driving source, a vacuum diode, and an experimental cavity. A Marx generator, a high energy storage water transmission line, and two pulse compression switches are utilized to generate a high voltage on diode. An effector can be placed in the experimental cavity which has the same vacuum as diode. An insulation structure of transmission line and a diode are optimized to guide in system design. The system can provide a multi-functional experimental platform for investigating pulse power technology, system-generated electromagnetic pulse, biological radiation effect, etc.</sec><sec> The Marx generator generates a high-voltage pulse with hundreds of nanoseconds in FWHM and hundreds of kilovolts in peak value. The pulse is compressed by the main switch and pulse forming switch and then loaded to the diode. Electrons are emitted from diode cathode under the high-voltage pulse and accelerated in the gap. The electrons are extracted directly or converted into X-ray through the anode. Aluminized polyethylene is used as an anode when pulsed electron beam is generated, and tantalum film is used when pulsed X-ray is generated. Working state can be switched by changing the cathode and anode of diode.</sec><sec> The result shows that a current of 83 kA pulsed electron beam and an average energy of 67 keV X-ray are generated. Pulsed X-ray has good uniformity and low electron proportion (0.02%). In order to monitor the operation state and output parameter of the system comprehensively, a complete measurement system is established. Three capacitive voltage dividers are set at the beginning of transmission line, the end of pulse forming line, and the end of output line, while a B - dot current monitor is set at the diode. A Faraday cup is developed to measure the current intensity and the total energy of pulsed electron beam. For energy spectrum, dose and electron proportion, the measurement system composed of pulsed X-ray including spectrometric system, dose system and Rogowski Coil is build.</sec>

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13

Lü, Ze-Qi, Yan-Zhao Xie, Ming-Yue Gou, Xiao-Yu Chen, Jin-Shan Zhou, Mei Li, and Yi Zhou. "Development of 200 kV multi-function pulsed radiation system." Acta Physica Sinica 70, no. 20 (2021): 205206. http://dx.doi.org/10.7498/aps.70.20210583.

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<sec>A multi-functional pulsed radiation system with a peak voltage of 200 kV, an impedance of 2 Ω, and a full width at half maximum (FWHM) of 30 ns is developed. The system can be switched flexibly in two states of generating pulsed electron beam and pulsed X-ray by changing the cathode and anode. It consists of a pulse power driving source, a vacuum diode, and an experimental cavity. A Marx generator, a high energy storage water transmission line, and two pulse compression switches are utilized to generate a high voltage on diode. An effector can be placed in the experimental cavity which has the same vacuum as diode. An insulation structure of transmission line and a diode are optimized to guide in system design. The system can provide a multi-functional experimental platform for investigating pulse power technology, system-generated electromagnetic pulse, biological radiation effect, etc.</sec><sec> The Marx generator generates a high-voltage pulse with hundreds of nanoseconds in FWHM and hundreds of kilovolts in peak value. The pulse is compressed by the main switch and pulse forming switch and then loaded to the diode. Electrons are emitted from diode cathode under the high-voltage pulse and accelerated in the gap. The electrons are extracted directly or converted into X-ray through the anode. Aluminized polyethylene is used as an anode when pulsed electron beam is generated, and tantalum film is used when pulsed X-ray is generated. Working state can be switched by changing the cathode and anode of diode.</sec><sec> The result shows that a current of 83 kA pulsed electron beam and an average energy of 67 keV X-ray are generated. Pulsed X-ray has good uniformity and low electron proportion (0.02%). In order to monitor the operation state and output parameter of the system comprehensively, a complete measurement system is established. Three capacitive voltage dividers are set at the beginning of transmission line, the end of pulse forming line, and the end of output line, while a B - dot current monitor is set at the diode. A Faraday cup is developed to measure the current intensity and the total energy of pulsed electron beam. For energy spectrum, dose and electron proportion, the measurement system composed of pulsed X-ray including spectrometric system, dose system and Rogowski Coil is build.</sec>

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14

YATSUI, KIYOSHI, KOUICHI SHIMIYA, KATSUMI MASUGATA, MASAO SHIGETA, and KAZUHIKO SHIBATA. "Characteristics of pulsed power generator by versatile inductive voltage adder." Laser and Particle Beams 23, no. 4 (October 2005): 573–81. http://dx.doi.org/10.1017/s0263034605050779.

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A pulsed power generator by inductive voltage adder, versatile inductive voltage adder (VIVA-I), which features a high average potential gradient (2.5 MV/m), was designed and is currently in operation,. It was designed to produce an output pulse of 4 MV/60 ns by adding 2 MV pulses in two-stages of induction cells, where amorphous cores are installed. As a pulse forming line, we used a Blumlein line with the switching reversed, where cores are automatically biased due to the presence of prepulse. Good reproducibility was obtained even in the absence of the reset pulse. Within ∼40% of full charge voltage, pulsed power characteristics of Marx generator, pulse forming line (PFL), transmission line (TL), and induction cells were tested for three types of loads; open-circuit, dummy load of liquid (CuSO4) resistor, and electron beam diode. In the open-circuit test, ∼2.0 MV of output voltage was obtained with good reproducibility. Dependences of output voltage on diode impedances were evaluated by using various dummy loads, and the results were found as expected. An electron-beam diode was operated successfully, and ∼18 kA of beam current was obtained at the diode voltage of ∼1 MV.

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15

Stankevic, Voitech, Povilas Simonis, Nerija Zurauskiene, Arunas Stirke, Aldas Dervinis, Vytautas Bleizgys, Skirmantas Kersulis, and Saulius Balevicius. "Compact Square-Wave Pulse Electroporator with Controlled Electroporation Efficiency and Cell Viability." Symmetry 12, no. 3 (March 5, 2020): 412. http://dx.doi.org/10.3390/sym12030412.

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The design and development of a compact square-wave pulse generator for the electroporation of biological cells is presented. This electroporator can generate square-wave pulses with durations from 3 μs up to 10 ms, voltage amplitudes up to 3500 V, and currents up to 250 A. The quantity of the accumulated energy is optimized by means of a variable capacitor bank. The pulse forming unit design uses a crowbar circuit, which gives better control of the pulse form and its duration, independent of the load impedance. In such cases, the square-wave pulse form ensures better control of electroporation efficiency by choosing parameters determined in advance. The device has an integrated graphic LCD screen and measurement modules for the visualization of the current pulse, allowing for express control of the electroporation quality and does not require an external oscilloscope for current pulse recording. This electroporator was tested on suspensions of Saccharomyces cerevisiae yeast cells, during which, it was demonstrated that the application of such square-wave pulses ensured better control of the electroporation efficiency and cell viability after treatment using the pulsed electric field (PEF).

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16

Koyano, Tomohiro, and Masanori Kunieda. "Electrochemical Micromachining Using Electrostatic Induction Feeding Method." Key Engineering Materials 523-524 (November 2012): 305–9. http://dx.doi.org/10.4028/www.scientific.net/kem.523-524.305.

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This paper describes micro electrochemical machining (ECM) using the electrostatic induction feeding method. In ECM, electrolytic dissolution can be localized in the area where the gap width is narrow by using pulse durations shorter than several tens of nano-seconds. With the electrostatic induction feeding method which has been developed for micro electrical discharge machining, the current pulse of such short durations can be obtained more easily compared with the conventional pulse generators. In this study, the influences of the pulse voltage of power supply and feeding capacitance on the machining current were investigated theoretically. It was found that the current pulse duration is nearly equal to the rise time and fall time regardless of the pulse-on time of the pulse voltage. Hence, ultra-short pulses can be obtained without a need to use an expensive pulse generator. Micro-hole drilling carried out in a sodium nitrate aqueous solution with current pulse duration of 30ns showed that significantly small side gap of 2μm could be obtained.

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17

Yan, Mu Tian, Yi Ting Liu, and Guan Ren Fang. "A Study on Pulse Generator for Micro WEDM of Polycrystalline Diamond." Key Engineering Materials 516 (June 2012): 498–503. http://dx.doi.org/10.4028/www.scientific.net/kem.516.498.

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This paper presents a new pulse generator for cutting of polycrystalline diamond (PCD) by micro wire-EDM. Three pulse control methods (AC power supply pulse control method, fixed pulse width modulation pulse control method and improved AC power supply pulse control method) have been proposed to achieve high frequency and low energy discharge pulses. The improved AC power supply pulse control method enables the pulse generator to provide a period of 20 μs off duty cycle followed by a period of duty cycle for reionization of the dielectric in the spark. Compared to the other two methods, the improved AC method can provide smaller peak current and discharge duration and thereby achieve a smaller slit width and better surface finish. Tests revealed that the developed power supply using anti-electrolysis circuitry and a digital signal processor-based pulse control circuit can provide very low discharge energy pulses with a frequency of 200 KHz, discharge duration of 0.75 μs and a peak current of 3 A. Experimental results demonstrate that the proposed pulse generator can achieve a feed rate of 0.4 mm/min, a surface finish of 0.53 μm Ra and a damaged layer of 5 μm on PCD surface through proper machining settings.

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18

Chernenko, N. A., A. V. Morozov, A. A. Myulbaer, N. V. Sheglov, S. S. Shevchenko, and I. V. Shmakov. "Rectangular current pulse generator to test varistors with pulsed electrical load." IOP Conference Series: Materials Science and Engineering 1089, no. 1 (March 1, 2021): 012018. http://dx.doi.org/10.1088/1757-899x/1089/1/012018.

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Zhang, Min, Qin He Zhang, De Zheng Kong, and Xue Bai. "Ringing Effect and Reversed Current Analysis of RC-Pulse Generator in Electrical Discharge Machining." Materials Science Forum 770 (October 2013): 183–88. http://dx.doi.org/10.4028/www.scientific.net/msf.770.183.

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RC-pulse generator has a simple structure and it is easy to be made and repaired. Especially RC-pulse generator can provide high frequency and low energy discharges. Therefore RC-pulse generators are used in micro-EDM field. But its high tool wear ratio and low efficiency restrict its applications. Ringing effect is considered to have effect on the defects. This research was done to study the ringing effect in electrical discharge. Taguchi method was used and discharge curves of voltage and current were recorded and analyzed. Ringing effect plays a key role in discharges and reversed current. A waveform model established with ringing effect theory is almost the same as the waveforms recorded in the experiment. Reversed current exists in almost a half time of discharge period which is the representation of ringing effect. Suitable process parameters can reduce reversed current and proper improvements could eliminate reversed current which will reduce the tool wear ratio and increase the efficiency in RC-pulse generator.

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Vignesh, S., B. Mohan, T. Muthuramalingam, and S. Karthikeyan. "Evaluation of Recast Layer Thickness of Electrical Discharge Machined AISI 202 Stainless Steel with Various Pulse Generators." Applied Mechanics and Materials 766-767 (June 2015): 518–22. http://dx.doi.org/10.4028/www.scientific.net/amm.766-767.518.

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Many of the recent developments in the fields such as aerospace, automobile and nuclear engineering industries are partly due to the increasing usage of difficult-to-machining materials. The machining of these materials is very tedious and time consuming process. Electrical discharge machining process has been developed to overcome these difficulties. It is very important to reduce the recast layer thickness of the machined workpiece using EDM process for improving the surface integrity. In the present study, an attempt has been made to study the effect of conventional transistor pulse generator and modified iso current pulse generator on recast layer thickness. In this study, machining experiments have been conducted on AISI 202 stainless steel with transistor pulse generator and iso energy pulse generator in electrical erosion process. The effects of these pulse generators on recast layer have been evaluated and analyzed. From the experimental results, it has been detected that the iso energy pulse generator has produced lower thickness of recast layer than conventional transistor pulse generator.

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21

Rogov, Aleksey B. "Smart Arbitrary Waveform Generator with Digital Feedback Control for High-Voltage Electrochemistry." Instruments 3, no. 1 (February 7, 2019): 13. http://dx.doi.org/10.3390/instruments3010013.

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This paper describes a design approach to a control system of power supply for high-voltage electrochemical processes such as plasma electrolytic oxidation (PEO) or high-voltage anodising (HVA), which require alternating polarisation pulses up to 750 V and a typical current density of 50–500 mA/cm2. Complex characteristics of the electrochemical system response on applied polarisations (positive or negative) cause necessity of precise control of polarising pulse shapes for better process operation and its understanding. A device performs cycle-by-cycle pulse-width modulation (PWM) control, including feedback based on digital analysis of the instantaneous current and/or voltage output, and the desired pulse waveform stored in memory for each output polarity. The output stage has four states corresponding to positive or negative pulses, as well as open- or short-circuit conditions, with respect to an electrochemical cell. A fully programmable controller allows one to generate arbitrary waveforms, as well as their sequences, by means of “regime designer” software. Moreover, a smart feedback system can provide adaptation of the next pulse parameter from analysis of the process prehistory. For instance, this approach allows one to separate main electrochemical process (coating formation) and diagnosis of the phenomenon through introduction of high-voltage triangular voltage sweep pulse within a pause of the main process, which is normally carried out under a current control.

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Lin, Ping, Bai Yu Liu, Yong Sheng Gou, Yong Lin Bai, Bo Wang, and Xue Qing Zhao. "Arbitrary Waveform Generator Based on GaAs FET and Tapered Micro-Strip Line." Advanced Materials Research 655-657 (January 2013): 1581–86. http://dx.doi.org/10.4028/www.scientific.net/amr.655-657.1581.

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In order to improve the output power of laser pulse in the inertia confinement fusion experiment, an arbitrary waveform generator is fabricated to shape the laser pulse. The arbitrary waveform generator is based on the impedance tapered micro-strip line technology and GaAs Field Effect Transistor set which has a good ability of generating voltage-controlled current. With the impedance tapered micro-strip line technology, the arbitrary waveform generator generates shaping electrical pulse with duration less than 10 ns, 330 ps time-domain adjustment. We use the shaping electrical pulse to modulate semiconductor laser which has the characteristic of direct modulate, the experiment results show the shaped laser pulse is obtained based on the shaping electrical pulse.

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Chuvatin, Alexandre S., Leonid I. Rudakov, Bruce V. Weber, Frédéric Bayol, and René Cadièrgues. "Current multiplier to improve generator-to-load coupling for pulse-power generators." Review of Scientific Instruments 76, no. 6 (June 2005): 063501. http://dx.doi.org/10.1063/1.1928450.

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24

Ueda, M., J. B. Greenly, D. A. Hammer, and G. D. Rondeau. "Intense ion beam from a magnetically insulated diode with magnetically controlled gas-breakdown ion source." Laser and Particle Beams 12, no. 4 (December 1994): 585–614. http://dx.doi.org/10.1017/s026303460000848x.

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A magnetically insulated diode with an active anode source has been developed which produces a high-quality intense ion beam. The anode plasma of annular shape is produced independently of the main diode power pulse by the inductive breakdown of a radially expanding gas cloud supplied by a fast puff valve and nozzle configuration. The diode was developed on a 1010-W pulsed power generator that typically produces 150-kV, l-μs pulses. Prompt ion beam turn-on was attained in this diode when an adequate delay between pulsing the plasma source and delivering the diode power pulse was chosen. The neutral atom density in the diode accelerating gap was sufficiently low that the presence of the neutrals did not limit the beam pulse duration. When the puff valve was filled with H2 gas, a pure proton beam was produced, within the 20% uncertainty of the measurement technique. Proton beam pulses longer than 1 μs and current densities higher than 100 A/cm2 at 70–150 keV were generated.

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25

SKOULAKIS, A., G. C. ANDROULAKIS, E. L. CLARK, S. M. HASSAN, P. LEE, J. CHATZAKIS, M. BAKAREZOS, et al. "A PORTABLE PULSED NEUTRON GENERATOR." International Journal of Modern Physics: Conference Series 27 (January 2014): 1460127. http://dx.doi.org/10.1142/s2010194514601276.

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The design and construction of a pulsed plasma focus device to be used as a portable neutron source for material analysis such as explosive detection using gamma spectroscopy is presented. The device is capable of operating at a repetitive rate of a few Hz. When deuterium gas is used, up to 105 neutrons per shot are expected to be produced with a temporal pulse width of a few tens of nanoseconds. The pulsed operation of the device and its portable size are its main advantage in comparison with the existing continuous neutron sources. Parts of the device include the electrical charging unit, the capacitor bank, the spark switch (spark gap), the trigger unit and the vacuum–fuel chamber / anode–cathode. Numerical simulations are used for the simulation of the electrical characteristics of the device including the scaling of the capacitor bank energies with total current, the pinch current, and the scaling of neutron yields with energies and currents. The MCNPX code is used to simulate the moderation of the produced neutrons in a simplified geometry and subsequently, the interaction of thermal neutrons with a test target and the corresponding prompt γ-ray generation.

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26

Kuznetsov, V. A., V. A. Kuznetsova, and O. A. Peregudov. "Electromechanical installation based on high power current pulse generator." Izvestiya. Ferrous Metallurgy 63, no. 9 (November 16, 2020): 755–62. http://dx.doi.org/10.17073/0368-0797-2020-9-755-762.

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27

DANESHVAR, K. "High current pulse generator for gain switching semiconductor lasers." International Journal of Electronics 69, no. 3 (September 1990): 379–84. http://dx.doi.org/10.1080/00207219008920323.

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28

Ma, Shangang, Xinjie Yu, and Zhen Li. "XRAM Pulse Current Generator With Magnetic Flux Compression Effect." IEEE Transactions on Plasma Science 45, no. 7 (July 2017): 1190–95. http://dx.doi.org/10.1109/tps.2017.2701001.

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29

Vizir’, V. A., S. V. Ivanov, V. I. Manylov, O. B. Frants, V. V. Chervyakov, and N. G. Shubkin. "A high-current pulse generator for gas discharge pumping." Instruments and Experimental Techniques 50, no. 2 (March 2007): 221–23. http://dx.doi.org/10.1134/s002044120702008x.

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30

Nguyen, Nhan Chi, Nghia Hoai Duong, and Anh Van Dinh. "Design and simulation of pulse generator for UWB based on LC-tank differential oscillators topology." Science and Technology Development Journal 18, no. 3 (August 30, 2015): 225–41. http://dx.doi.org/10.32508/stdj.v18i3.840.

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This paper presents a detailed analysis, design and simulation of pulse generator for Ultra-Wideband (UWB) based on LC-tank differential oscillators topology. The differential oscillators with a cross-coupled NMOS pair and a tail current source are used to achieve more positive gain and generate negative resistance to the LC-tank. Besides, this oscillator is suitable for UWB high frequency and low power applications. The UWB pulse generator is composed of a simple on-off keying (OOK) modulated and LC-tank differential oscillators. The circuit of UWB pulse generator designed and simulated in 0.13 um CMOS technology. The UWB pulse generator generates a pulse for the 6 - 10 GHz UWB transmitter. Simulation results show a pulse width of 586 ps, a peak to peak amplitude pulse of 88.6 mV from the 1.2 V power supply and the die area of 0.22 mm2. The average power consumption of approximately 0.55 mW and an energy consumption of 1.1 pJ/pulse at 500 MHz pulse repetition rate (PRR) are observed.

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31

Kolpakhchyan, P. G., and D. V. Olkhovatov. "Sensorless control of the high-speed switched reluctance generator of the micro power plant." Vestnik of Don State Technical University 19, no. 4 (January 3, 2020): 357–65. http://dx.doi.org/10.23947/1992-5980-2019-19-4-357-365.

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Introduction. In the distributed and autonomous generation systems using renewable energy sources, low-power generating units (not more than 100-200 kW) based on microturbines function. Microturbines operate most efficiently at high rotational speeds. In this regard, the generator running with a microturbine must also be a high-speed one. A generator is a switched reluctance electric machine (EM) that needs information on the rotor position. It is difficult to use a position sensor in such mechanisms at high speeds. This paper discusses the issues of sensorless control of a high-speed switched reluctance electric generator in conjunction with a steam microturbine.Materials and Methods. So, it is required to evaluate the proof-of-principle developed to control a high-speed switched reluctance EM. For this purpose, a mathematical model has been created including models of the investigated EM, an electric power converter, and a control system. For the EM under consideration, the active resistance is determined, as well as the dependence of the phase flux linkage on the current flowing through it and the position of the moving element. The method used involves probing the idle phase of an electric machine with short voltage pulses of equal duration, and measuring the current in this phase. If the voltage pulse length is much shorter than the phase time constant, then the current pulse amplitude is inversely proportional to the inductance. Thus, registering the maximum current pulse amplitude, it is possible to determine the rotor passage through an uncoordinated position for the probed phase. This information is used to form control actions by other phases. Moreover, the length of the test voltage pulses, required to obtain current pulses sufficient for measuring the value, is of significance versus the duration of the pulsing time. Hence, with an increase in the rotational speed, the number of test pulses is insufficient for measuring the position with the accuracy required for the control goals. This reduces drastically the precision of determining the rotor position; therefore, at high speeds, the application of this method is limited without further refinement of the rotor position. In this case, to increase the precision of measurements, it is necessary to evaluate the rate of current rise when applying the basic voltage pulse or the voltage pulse rate forming the phase current before switching to a single-pulse control mode. Research Results. Two conclusions important for correcting the estimation of the rotor position in a single-pulse operation mode of a reluctance EM are proved. The first conclusion is on the efficiency of the proposed technique of filtering phase current measurement data, the second one concerns the applicability of the identified information criteria. The analysis results of the processes in the switched reluctance EM using sensorless control that implements the described principles for determining the rotor position are presented.Discussion and Conclusions. To correct the estimation of the rotor position, the following information criteria can be used: the presence of a pause between the excitation pulse and the start of the generation process; the decrease in current by the time the generation begins. To refine the estimate, the following fact can be used: on the generation interval, the current curve knee corresponding to the maximum phase inductance is observed at the same rotor position.

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32

Pirc, Eva, Damijan Miklavčič, Katja Uršič, Gregor Serša, and Matej Reberšek. "High-Frequency and High-Voltage Asymmetric Bipolar Pulse Generator for Electroporation Based Technologies and Therapies." Electronics 10, no. 10 (May 18, 2021): 1203. http://dx.doi.org/10.3390/electronics10101203.

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Currently, in high-frequency electroporation, much progress has been made but limited to research groups with custom-made laboratory prototype electroporators. According to the review of electroporators and economic evaluations, there is still an area of pulse parameters that needs to be investigated. The development of an asymmetric bipolar pulse generator with a maximum voltage of 4 kV and minimum duration time of a few hundred nanoseconds, would enable in vivo evaluation of biological effects of high-frequency electroporation pulses. Herein, from a series of most commonly used drivers and optical isolations in high-voltage pulse generators the one with optimal characteristics was used. In addition, the circuit topology of the developed device is described in detail. The developed device is able to generate 4 kV pulses, with theoretical 131 A maximal current and 200 ns minimal pulse duration, the maximal pulse repetition rate is 2 MHz and the burst maximal repetition rate is 1 MHz. The device was tested in vivo. The effectiveness of electrochemotherapy of high-frequency electroporation pulses is compared to “classical” electrochemotherapy pulses. In vivo electrochemotherapy with high-frequency electroporation pulses was at least as effective as with “classical” well-established electric pulses, resulting in 86% and 50% complete responses, respectively. In contrast to previous reports, however, muscle contractions were comparable between the two protocols.

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33

Blaschenko, O. D., E. P. Razmenov, and I. M. Starkov. "Modernization of Control of Switching-on the Circuits of a Two-Circuit Pulse Current Generator." Elektronnaya Obrabotka Materialov 58, no. 1 (February 2022): 93–100. http://dx.doi.org/10.52577/eom.2022.58.1.93.

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A possibility of developing control devices for switching on circuits in double-circuit pulse cur-rent generators in various discharge-pulse technologies is shown. The advantages of using those devices in the technology of a high-voltage electrochemical explosion are described, which requires a specific energy input based on the time delays between switching on the circuits. A scheme is proposed for automatically starting the second circuit in a double-circuit pulse current generator, which provides smooth (non-discrete) adjustment of the time delay of operation and realizing a wider range of delay times

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34

Remnev, G. E., Mikhail V. Zhuravlev, M. V. Belyakov, I. A. Koryashov, I. N. Pyatkov, M. I. Kaikanov, and A. V. Tikhonov. "HIGH-POWER DOUBLE-PULSE GENERATOR FOR POWER SUPPLY TO PULSED HIGH-CURRENT ACCELERATOR." High Temperature Material Processes An International Quarterly of High-Technology Plasma Processes 21, no. 4 (2017): 309–15. http://dx.doi.org/10.1615/hightempmatproc.2018025165.

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35

Adamyan, Yuri, Sergey Krivosheev, and Tatyana Minevich. "Investigation of the wind generator blades material resistance to the lightning current action." MATEC Web of Conferences 245 (2018): 15001. http://dx.doi.org/10.1051/matecconf/201824515001.

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This paper is devoted to the problems of lightning protection of composite materials of wind generator blades. The results of experimental studies for carbon fibers under different types of lightning current pulse effects are provided. A significant increase in the degree of destruction of materials is shown for the pulse approximating field experiment results as compared with the standard lightning current pulse. We show that under the impact of the standard current pulse there is no significant material destruction, and the release of the discharge products is also insignificant. Also we shown that under the impact of the current pulse having a long «tail» time period (the current pulse close to the real one) there is an ignition of the carbon fiber composite material near the edges of the feeding electrode. With this the burning process doesn’t end after the end of the current pulse. The description of the pulse current generator created for experiments is given.

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36

Porvatov, Artur, Mikhail Kozochkin, Ilya Minin, Andrey Maslov, Vladimir Kuptsov, Marian Morozkin, Vladimir Kuznetsov, Marko Leonesio, Alexander Zelensky, and Petr Pivkin. "Application of Circuit Modeling in the Study of Spark Formation During Electroerosion Treatment." EPJ Web of Conferences 248 (2021): 04016. http://dx.doi.org/10.1051/epjconf/202124804016.

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Electrical discharge machining (EDM) of a workpiece is a complex, fast-flowing process characterized by alternating (intermittent) states: short circuit, idle and spark formation. The discontinuity of the EDM process means that the processing is carried out in single pulses, which are formed by a special pulse generator. The parameters of the generator pulses can be divided into time and electrical. The time period and duration of the pulses, as well as the difference between these two parameters (the “silence” interval), are considered temporary. The electric ones include the amplitude value of the voltage, the maximum permissible current, and the polarity of the pulses. in addition, depending on the device of the generator, the pulses can be composite, for example, have an igniting pulse with a higher voltage and a lower current than the main (working) pulse. In this work, we have developed a interelectrode gap model that allows not only to obtain values of electrical parameters, but also to evaluate and to optimize the electrical parameters of materials being processed with known electrical properties. The key advantage of this model is its modularity, which allows to add new functional blocks, which describe external and internal influences, for example, the concentration of erosion products, uneven electrical conductivity of the workpiece, and others, without changing its structure.

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37

Erawan, Minhat Ade, Khamis Nor Hisham, Azli Yahya, Andromeda Trias, Juli Purwanto Nugroho Kartiko, Safura Hashim Nor Liyana, Mahmud Nazriah, and M. Daud Razak. "Control Strategy for Electrical Discharge Machining (EDM) Pulse Power Generator." Applied Mechanics and Materials 554 (June 2014): 643–47. http://dx.doi.org/10.4028/www.scientific.net/amm.554.643.

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Electrical Discharge Machining (EDM) is a advanced machine that can control electrical spark to erode metal on the workpiece. In manufacturing, EDM is used on hard material parts that are extremely difficult to machine by conventional machining processes. EDM system consists of a shaped tool and the work piece, which are connected to a power supply and placed in a dielectric fluid. EDM pulse power generator applies voltage and current pulses between the electrode and workpiece to generate sparks through the gap. To obtain the optimum metarial removal rate (MRR), a good alternative is to improve the gap voltage and gap current. A proposed solution to these issue is combining ultracapacitor bank to the main power supply circuit for EDM machines. The control feedback of this research is designed to make sure that the current on DC bus is maintained at current setting during the machining processes.

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38

Chuaqui, H., E. Wyndham, C. Friedli, and M. Favre. "LLAMPÜDKEÑ: A high-current, low-impedance pulser employing an auxiliary exponential transmission line." Laser and Particle Beams 15, no. 2 (June 1997): 241–48. http://dx.doi.org/10.1017/s0263034600010569.

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The design and constructional aspects of a novel pulse power generator for use in dense plasma research presently under construction are presented. The generator consists of two Marx capacitor banks, each of 0.25 μF, 480 kV, and 28.8 kJ. Each Marx generator drives a water transmission line, in which the live electrode is the central conductor. The transmission lines consist of a constant impedance section followed by a multielectrode gas linegap followed by an exponential taper to the load section. The novel feature is the use of an auxiliary exponential line coupled at the load. This line controls both the voltage and the effective impedance at the load section. In addition, by leaving this line circuit open, energy not coupled to the plasma in the initial high-impedance phase may be reflected back and deposited into the discharge, increasing the peak current by 50%. Circuit simulations using a real-time-varying load impedance show that the current pulse rises in an approximately linear way to a maximum of 1.2 MA at 250 ns. The current falls to zero in the following 250 ns. The current waveform may be flattened simply by disconnecting the auxiliary line, giving a rectangular pulse of 350 ns with a maximum value of 950 kA. The overall impedance of the entire system may be adjusted by varying the separation between the conductors. The equivalent source impedance at the load is 0.8 Ω. This low value is by virtue of the auxiliary line, which limits the voltage at the load section and reduces the insulator constraints. We present simulations of the generator under real load conditions. The model also is checked against analytical solutions of exponential line behavior and against other published models of pulse power generators.

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39

Hu, Zhao Yu, Jun Xu, Shen Du Luo, and Mao Hui Yang. "The Design of Fast Pulse Power Generator with Low Voltage." Applied Mechanics and Materials 40-41 (November 2010): 327–30. http://dx.doi.org/10.4028/www.scientific.net/amm.40-41.327.

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In recent years, nanosecond pulse power techniques used in the millimeter-wave solid-state pulse power amplifiers attracted much attention. The rise- and fall-time of the pulse, the flatness of pulse-top and the stability of pulse-to-pulse, which have play important roles in a nanosecond pulse power generator techniques, and directly determine the system performance. In this paper, a method using the outbreak current with low-voltage to drive MOS-FETs is proposed. The measured results show that the rise- and fall-time of the output pulse is less than 1.5 ns with a pure resistance 0.5Ω, and it only needs two 12V power supply to give a output current of 20A with a pulse width of 160 ns at a repetition rate of 540 kHz in continuous mode. A flatness of 3% for the output voltage was obtained,which meet the requirements of ka-band solid-state millimeter-wave pulse power amplifier.

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40

Erawan, Minhat Ade, Azli Yahya, Khamis Nor Hisham, Ahmad Saudi Samosir, Muhammad Arif Abdul Rahim, Andromeda Trias, and Juli Purwanto Nugroho Kartiko. "Model of Pulse Power Generator in Electrical Discharge Machining (EDM) System." Applied Mechanics and Materials 554 (June 2014): 613–17. http://dx.doi.org/10.4028/www.scientific.net/amm.554.613.

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Electrical discharge machining (EDM) is a non-traditional manufacturing process of removing material. EDM system consists of a shaped tool and the work piece, which are connected to a power supply and placed in a dielectric fluid. EDM pulse power generator applies voltage pulses between the electrode and workpiece to generate sparks through the gap. The essential requirement for EDM system is to obtain the output waveform similar to the ideal EDM waveform. The design is based on transistor type pulse power generator circuit. This paper discuss in modeling of current and voltage gap waveform for EDM system.

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41

Bilovol, Vitaliy, Claudio Barbon, and Bibiana Arcondo. "Current-voltage curves of eutectic In-Sb-Te thin films for phase change memory devices." Microelectronics International 36, no. 4 (October 7, 2019): 165–70. http://dx.doi.org/10.1108/mi-01-2019-0007.

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Purpose The purpose of this paper is to investigate electrical properties of eutectic In8Sb8Te84 and In10Sb51Te39 as made thin films to evaluate their potential for non-volatile phase-change memories, once the thermal measurements are very optimistic. Design/methodology/approach The films were deposited by pulse laser deposition technique. By using a very simple home-made cell, transversal current-voltage curves films were measured involving both voltage controlled-pulses generator and current controlled-pulses generator, employing different pulse shapes: triangular and sine shaped. Findings The memory effect, characteristic of a typical phase-change memory material, was observed in both materials under research. For higher tellurium content in the film, lower is the value of threshold voltage. Research limitations/implications Further studies on endurance, scaling and SET/RESET operations are needed. Practical implications The values of the key parameters, threshold voltage and hold voltage are comparable with those of Ge2Sb2Te5, GeTe and Sb2Te being considered to date as the main compounds for PCM devices. Originality/value The conduction mechanism in the amorphous regime is agreed with Poole–Frenkel effect in deep traps.

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Cassabli, Salam Bussi EP Michel, G. M. Suchkov, S. Yu Plesnetsov, R. P. Mygushchenko, O. Yu Kropachek, and Yu O. Plesnetsov. "GENERATOR OF POWERFUL HIGH-FREQUENCY PACKAGE CURRENT PULSES FOR POWER SUPPLY OF ULTRASONIC ELECTROMAGNETIC-ACOUSTIC TRANSDUCERS." METHODS AND DEVICES OF QUALITY CONTROL, no. 2(43) (December 24, 2019): 88–95. http://dx.doi.org/10.31471/1993-9981-2019-2(43)-88-95.

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It is possible to increase the sensitivity of electromagnetic-acoustic transducers by three main methods: increasing the induction of a polarizing magnetic field; increase in strength of high-frequency current in the inductor of the converter; using modern methods of processing information packet pulses excited and received from the product. The increase in magnetic field induction of the converter is limited by the capabilities of modern powerful permanent magnets. In addition, there are significant difficulties in monitoring ferromagnetic control samples, due to the large pressing force between the sample and the transducer and sticking of scale to the transducer. Usage of modern processing methods significantly complicates and increases the cost of electromagnetic-acoustic testing devices. Of the selected sensitivityincreasingmethods, the most acceptable way is to increase the power of high-frequency current generators under the condition of excitation of packet pulses. Power supply process of the converter is carried out in two stages. Meander type powerful high-frequency current pulses are excited, which ensures operation of the output transistors in key mode. Isolation of a powerful sinusoidal high-frequency packet current pulse is carried out directly on the electromagnetic - acoustic transducer, the elements of which are included in the resonant circuit with low quality factor. Based on the transistors switched in the push-pull circuit in the key mode, a small-sized generator design has been created that excites a peak current of up to 800 A in the electromagnetic-acoustic transducer and a voltage of up to 3 kV in the transducer in the frequency range 0.3 ... 8 MHz. It was experimentally determined that the new design of the probe pulse generator made it possible to increase the amplitude of pulses reflected from a flat-bottom reflector with a diameter of 2 mm with respect to the interference amplitude by more than 2 times.

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43

Gorbachev, K. V., E. V. Nesterov, V. Yu Petrov, and E. V. Chernykh. "A helical-radial magnetic cumulation fast-growing current pulse generator." Instruments and Experimental Techniques 52, no. 1 (January 2009): 58–64. http://dx.doi.org/10.1134/s0020441209010096.

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44

Ting, Joseph W., Daniel J. Rubins, D. ‐J Huang, and J. L. Erskine. "A high current pulse generator for magnetizing thin magnetic films." Review of Scientific Instruments 67, no. 11 (November 1996): 3948–50. http://dx.doi.org/10.1063/1.1147296.

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45

Lin, Ming-Shian. "A Regulated Pulse Current Driver with Spread Spectrum Clock Generator." Electronics 10, no. 21 (October 30, 2021): 2661. http://dx.doi.org/10.3390/electronics10212661.

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This paper presents a regulated pulse current driver with a spread spectrum clock generator (SSCG) to lower the electromagnetic interference (EMI) effect. An SSCG is used and implemented by applying a triangular wave to modulate a voltage-controlled oscillator (VCO). The results show a 7 dBm reduction in the peak power level with a frequency deviation of 10%, demonstrating that the dominate harmonic is spread and distributed to adjacent frequencies, and the magnitude of harmonics is significantly reduced. The results demonstrate that the driver with a spread spectrum clock generator would help to reduce interference in sensitive electronic components and be suitable for portable consumer electronics applications.

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46

Lan, Yu Dan, and Li Ming He. "Electrical Characteristics Investigation of Transient Plasma Ignition." Applied Mechanics and Materials 110-116 (October 2011): 503–7. http://dx.doi.org/10.4028/www.scientific.net/amm.110-116.503.

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A pseudo-spark based high repetition pulse generator is used, and a rapid charger (3μF) is used for repetitive discharge, and the frequency of typical discharge is 10 kHz. The pulse generator can provide pulse with duration of 1~2μs, which can be generated at 10~100 kHz maximum repetition rate in burst mode, with amplitudes up to 140 kV and 7 J of energy per ignition pulse. This paper studies the changing laws of voltage and current in TPI under different electrodes and discharge voltages. The result indicates that the use of screw thread electrode can increase the discharge times of TPI, reduce applied voltage without reducing the peak burst power. With the same time, TPI can raise the pulse energy and reduce pulse time by increasing voltage.

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47

Lee, Jeong Ki, Dong Man Suh, and Seung Seok Lee. "Change of the Pulsed Eddy Current Signals by the Variation of the Thickness of an Aluminum Specimen." Key Engineering Materials 297-300 (November 2005): 2028–33. http://dx.doi.org/10.4028/www.scientific.net/kem.297-300.2028.

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The conventional eddy current testing uses a sinusoidal signal with very narrow frequency bandwidth. Whereas, the pulsed eddy current method uses a pulse signal with a broad frequency bandwidth. This allows multi-frequency eddy current testing, and the penetration depth is greater than that of the conventional eddy current testing. In this work, the pulsed eddy current instrument was developed for evaluating the metal loss. The developed instrument was consist of the pulse generator generating the square pulse of maximum 40 V, the amplifier controlled to 52dB, the A/D converter of 16bit 20MHz, and the industrial personal computer for operating with Windows program. And, the probe for the pulsed eddy current was designed as the pancake type in which the sensing coil was located in the driving coil. The peak voltage did not linearly increase with the voltage of the step pulse. For the driving coil with inductance of 670µH, the peak voltage linearly increased with the step pulse voltage to 30V. But, for the other driving coils with the inductance of 1.7mH, 2.7mH, 3.6mH, 22mH, the peak voltage linearly increased with the step pulse voltage to 20V. The output signals of the sensing coil rapidly increased when the step pulse driving voltage was off, and the latter part of the sensing coil output voltage exponentially decreased with a time. The decrement value of the output signals of sensing coil increased with the thickness of the aluminum test piece.

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48

Muthuramalingam, T., and B. Mohan. "Enhancing the Surface Quality by Iso Pulse Generator in EDM Process." Advanced Materials Research 622-623 (December 2012): 380–84. http://dx.doi.org/10.4028/www.scientific.net/amr.622-623.380.

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In automobile and aeronautical industries, complex moulds and dies is produced by Electrical Discharge Machining process. The surface finish is determined by the crater volume in EDM process. The amount of crater volume is influenced by the amount and distribution of discharge energy. The discharge energy is directly proportional to the average discharge current. This amount of current is determined by the duration of discharging effect. This study deals about evaluating the performance of iso current pulse generator on machining characteristics in EDM. Due to its ability of reducing stochastic nature in EDM process, iso pulse generator could produce better surface finish than conventional transistor pulse train generator with higher material removal rate.

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Li, Song, Jing-Ming Gao, Han-Wu Yang, and Bao-Liang Qian. "A high-voltage, long-pulse generator based on magnetic pulse compressor and Blumlein-type rolled strip pulse forming line." Laser and Particle Beams 33, no. 3 (July 1, 2015): 511–18. http://dx.doi.org/10.1017/s0263034615000567.

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AbstractIn this paper, a new technical scheme of high-voltage, long-pulse generator, mostly based on solid-state power devices, including magnetic pulse compressor, Blumlein-type rolled strip pulse-forming line (RSPFL) and inductive voltage adder (IVA), is proposed and investigated numerically and experimentally. The generator has potential advantages of high average power level, high repetitive rate capability, long lifetime, and long pulse achievability, which meet the requirements of military and industrial application of the pulsed power technology. Specifically, a two-stage magnetic pulse compressor was set up with iron-based amorphous cores. Total compression ratio of the device is approximately 12 and the achieved voltage efficiency is up to 92%. Low impedance, long-duration Blumlein-type RSPFL was established with characteristic impendence and electrical length of 3 Ω and 100 ns, respectively. Mylar film was selected as the solid-state dielectric. Increased by a four-stage IVA, typical quasi-square pulse was obtained with peak current of 2.3 kA and duration over 200 ns. As the resistance of the dummy load was measured to be 60 Ω, the peak voltage was approximately 138 kV. Experiments show reasonable agreement with numerical analysis.

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Popović, I., V. Rajović, and M. Zlatanović. "Dynamic Voltage-Current Characteristics of Unipolar Pulse Glow Discharge." Materials Science Forum 494 (September 2005): 315–20. http://dx.doi.org/10.4028/www.scientific.net/msf.494.315.

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Introduction of pulse plasma power supply is one of the major contributions to plasma surface engineering. The voltage and current waveforms of nitrogen and nitrogen/hydrogen glow discharges in the vacuum total pressure range from 0.1 to 15 mbar were recorded and analyzed concerning the shape, typical operating values and the influence of surface treatment process parameters. It was found that the waveform shape of the voltage and current contains information on pulse generator output parameters and vacuum system properties during normal glow, hollow cathode discharge and arcing. We have also performed the scoping of dynamic parameters and static characteristic, in order to obtain information for the generator and chamber modeling, to be used in a future plasma materials treatment processes control. The influence of process parameters such as total pressure, cathode temperature and biasing voltage on current-voltage characteristics was also considered.

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