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The article offers information on the requirements for the submission of manuscripts to the journal's special issue dedicated to the joint conferences, such as the Euro-Asian Pulsed Power Conference and the 21th International Conference on High-Power Particle Beams.

The combined IEEE International Conference on Plasma Science (ICOPS) (held annually) and Pulsed Power Conference (held biennially) are merged once every six years, sponsored by the Plasma Science and Applications Committee (PSAC) and the Pulsed Power Science and Technology Committee (PPS&T) of the IEEE Nuclear and Plasma Science Society (NPSS). The joint conference, called the Pulsed Power and Plasma Science Conference, was held on June 23–28, 2019, in Orlando, FL, USA. The conference’s technical program included a wide range of topics, which ranged from fundamental research to traditional and emerging technology applications. The conference had over 800 accepted abstracts, representing scientists from over 30 countries. The program also included a minicourse on “Computational Methods in Plasma Physics.” This year the PPPS sessions were enhanced by a number of exceptional plenary talks. [ABSTRACT FROM AUTHOR]

Describes the above-named upcoming special issue or section. May include topics to be covered or calls for papers. [ABSTRACT FROM AUTHOR]

The joint conference of the 6th Euro-Asian Pulsed Power Conference (EAPPC 2016), the 21st International Conference on High-Power Particle Beams (BEAMS 2016), and the 15th International Conference on Megagauss Magnetic Field Generation and Related Topics (MEGAGAUSS 2016) was held in Estoril, Portugal, on September 18–22, 2016. It was the first time that researchers from these three areas, although closely related, have come together to share their findings following an integrated scientific program. [ABSTRACT FROM PUBLISHER]

Prospective authors are requested to submit new, unpublished manuscripts for inclusion in the upcoming event described in this call for papers. [ABSTRACT FROM PUBLISHER]

This is a Special Issue containing selected papers presented at the 5th Euro-Asian Pulsed Power Conference (EAPPC) in Kumamoto, Japan, held on September 8-12, 2014. The present Special Issue continues the tradition of chronicling the latest advances in the domain of pulsed-power science and technology. [ABSTRACT FROM PUBLISHER]

Describes the above-named upcoming special issue or section. May include topics to be covered or calls for papers. [ABSTRACT FROM PUBLISHER]

An introduction is presented to the October 2015 special issue of the journal "IEEE Transactions on Plasma Science," featuring papers to be presented at the September 2014 Euro-Asian Pulsed Power Conference (EAPPC) in Kumamoto, Japan.

A new modular pulsed-power source with fast rise time and step-wise arbitrary output waveform generation is currently under development to drive the Gepulste Elektronenstrahlanlage device investigated at the Institute for Pulsed Power and Microwave Technology (IHM). Acknowledging the complex design procedures necessary to set up a modular pulsed-power source for voltages of up to 120 kV, this paper focuses on the circuit design for a single stage and its validation prior to the generator assembly. Using a semiconductor-based Marx generator topology, the stages are designed to have an output voltage of 1 kV with a pulse current of up to 600 A. When connected to an ohmic load, the measured current rise times are in the order of 46 ns resulting in the current rise rates of up to 10 kA/ $\mu \text{s}$ using the commercial devices. The step-wise arbitrary output waveform is created by generating the switching commands on the stage using a microprocessor and a fast optical synchronization unit. Effective stage shielding is verified by operating the stage in a 100-kV, 2.5-kA electromagnetic interference test bed. This paper presents the design considerations and the corresponding measurements. [ABSTRACT FROM AUTHOR]

This paper introduces the work undertaken to reliably use off-the-shelf differentiating voltage probes attached to coaxial transmission lines. The results obtained prove that indeed such probes are a valid and simple instrument for measuring nanosecond and subnanosecond voltage impulses. As a bonus, this paper also highlighted an important challenging phenomenon that appears whenever an attempt is made to measure fast voltage impulses with a differentiating probe positioned too close to the closing switch of a pulse forming line generator. [ABSTRACT FROM AUTHOR]

By triggering the switches in sequence and controlling the brick charging voltage independently, a pulsed power system can generate flexible current waveform in the load, which could allow high-accurate magnetic pressure in experimental materials in the study of EOS data and dynamic response of material characterization. Currently, a 1.5-MA driver with 20 independent bricks has been developed, and a programmable 256-brick parallel discharge driver which is able to generate shaped current greater than 6.5 MA is under construction in the China Academy of Engineering Physics. In this paper, for these two multibrick parallel discharge drivers, the method of optimizing the output current waveform of the driver is studied by using the genetic algorithm and the corresponding optimization results of different target current waveforms are obtained. An experimental platform is set up for studying the gas switch breakdown characteristics. The self-breakdown and triggering breakdown experiments of the switch are conducted, and its breakdown characteristics are researched. Meanwhile, the effect of breakdown delay and jitter on the output current waveform is studied by simulation. This paper is of great significance to the actual operation of the multibrick parallel discharge drivers. [ABSTRACT FROM AUTHOR]

Railguns are current-driven guns that allow reaching large muzzle velocities and energies. In the military context, the long-range artillery scenario makes use of these two capabilities to enable the launch of hypervelocity projectiles to target distances above 100 km. As of today, the most advanced railgun project is conducted by the Office of Naval Research, Arlington, VA, USA, and features railguns with a muzzle energy of 32 MJ. Such large artillery railgun systems with efficiencies above 30% are fed by a pulsed power system with a nominal energy content of about 100 MJ. In contrast to this, experiments with French-German Research Institute’s (ISL) most powerful railgun, PEGASUS, have reached muzzle energies of 2 MJ, only. The nearer future ISL has to answer two questions: 1) is the railgun technology adequate for a long-range artillery scenario? 2) can the railgun launch a hypervelocity projectile which is being developed by other groups in ISL? To do so and to support the development of the hypervelocity projectile, a larger railgun installation with a significant increase of the energy and free flight capability is required. In this paper, three different railgun systems were investigated using an electric circuit simulation code. The systems are referred to by the energy being stored in the capacitors as 25, 50, and 100 MJ. The aim of this paper is to investigate what masses can be accelerated to the relevant velocity range for the long-range artillery scenario by these different primary energies. The results of this paper can be used to aid the decision about the required size, with respect to the military scenario, of a potential future railgun system. [ABSTRACT FROM AUTHOR]

Presents the table of contents for this issue of the publication. [ABSTRACT FROM PUBLISHER]

This paper presents the effect of stray capacitances in bipolar (negative and/or positive) pulses generated by the two different topologies of the solid-state Marx modulators. According to the analysis, the stray capacitances influence the energy transfer from the Marx modulator capacitors to the load affecting the bipolar (negative and/or positive) pulse rise time. This paper deals with the structure design to reduce the influence of the stray capacitance and to improve the pulse rise time of these bipolar solid-state Marx modulators. A four-stage laboratory prototype of the two topologies has been assembled using 1200-V insulated gate bipolar transistors and diodes, operating with 1000-V dc input voltage and 1-kHz frequency, producing 4-kV bipolar pulses, with 5- \mu \texts pulse duration and 120-ns rise time, into a resistive load. [ABSTRACT FROM PUBLISHER]

This paper discusses the design, fabrication, and analysis of a coil assembly for a multistage induction-type coilgun system with the pulsed power module. The voltage, current, force, velocity, acceleration, and efficiency of the coilgun system were analyzed using the finite-element method. Based on the results of the electromagnetic analysis, the geometry of the coil assembly part for coilgun system was defined. The designed coilgun system has been found to exhibit high energy efficiency and safety against the force and temperature of the coil assembly. The designed coil assembly part was fabricated and analyzed. The design specifications and analysis results concerning the coilgun can, hence, be effectively utilized to develop a large-scale multistage induction-type coilgun system. [ABSTRACT FROM AUTHOR]

A pulsed electromagnetic inductive valve has been developed to achieve correct initial deposition of the propellant gas puff for the planar pulsed inductive plasma thruster. This paper aims to describe the method for modeling the valve. The most significant physical effects involved in the valve operation process are described by the electrical model, the magnetic model, the mechanical model, and the pneumatic model. These physical models are then linked together based on the couplings between them to form a complete multiphysics coupling model. In order to validate the proposed model, simulations and experiments are implemented for the prototype valve at different operating conditions. Response characteristics and throughput characteristics predicted by the model agree well with experimental data. The results demonstrate that the proposed model can be successfully applied to accurately capture the main performance of the valve. The principle of the analysis procedure is applicable to other electromagnetic valves of this type. [ABSTRACT FROM AUTHOR]

Due to the volume and weight of the coaxial Blumlein pulse forming line (B-PFL) with liquid energy storage medium are very large and energy storage density is relatively small, a new solid-state coaxial B-PFL is designed for the pulsed power technology in this paper. There are three conductor cylinders in the pulse forming line (PFL): inner cylinder, middle cylinder, and outer cylinder. Ferroelectric ceramics is selected as the energy storage medium which is between the middle cylinder and inner cylinder, and middle cylinder and outer cylinder. The impedance, electric length, parameters such as pulsewidth and its required physical length calculation formula of the PFL is deduced, based on the coaxial cable of the related parameter calculation formula. The formula for determination of relative suitable radius size is obtained. The simulation of electric field of PFL is implemented in the simulation software Ansoft Maxwell, and the results show that the design of the coaxial B-PFL is feasibility. The pulse forming principle has carried on the detailed validation in the simulation software PSPICE, and the results show that the design scheme of PFL is feasible. The application of the PFL can largely reduce the volume and weight of the pulsed power device, and it has a good application prospect. [ABSTRACT FROM AUTHOR]

The trend to move toward the solid-state and repetitive pulsed power supply requires the high-voltage, high-current, and high-speed semiconductor devices, which makes an insulated gate bipolar transistor (IGBT) preferred for this application. However, as a bipolar device, the IGBT is limited by the switching speed and switching loss. In this paper, the potential of silicon carbide (SiC) metal-oxide-semiconductor field-effect transistor (MOSFET) for the pulsed power application is investigated. The surge current capabilities of 1.2-kV, 30-A commercial Si IGBT and SiC MOSFET are characterized and compared by the capacitor discharge experiment. In addition, the effects of various circuit parameters, including gate resistance, dc-link voltage, and dc-link capacitance, on the capacitor discharge process are investigated. It is found that the pulse current of SiC MOSFET is around two times of Si IGBT, which achieves good agreement with the datasheet. Using $di/dt$ to represent the discharging speed, the SiC MOSFET is 10 times faster than the Si IGBT. It is because the SiC MOSFET shows a lower ON-resistance in the saturation region resulted from the short-channel effect. This paper confirms the high-speed and high-current advantages of SiC MOSFET in the pulsed power application. [ABSTRACT FROM AUTHOR]

Multilayer dielectric barrier discharge (DBD) can efficiently enlarge the volume of homogeneous plasma and its interactional surface area with materials in vertical space, which seems attractive to the industry application. In this paper, a new plasma generator of DBD structure which has multilayers of dielectric barrier boards excited by repetitive submicrosecond pulsed power (0 to -100 kV, 130 Hz-1 kHz, pulsewidth 230 ns, and rise time 120 ns) is introduced, and homogeneous plasma has been obtained in atmospheric pressure air. Experiments on high-speed photography with an exposure time of 5 ns have been carried out to the discharge with three layers of dielectric barrier boards with each gap width of 2 mm. It demonstrates that luminance of the discharge distributes uniformly throughout the upper and the lower gaps. Also, the result of the time evolution image of a three-layer DBD is discussed in this paper, which shows that the two layers of luminous intensity keep good consistency with each other, and this indicates that breakdown of each gap layer happens at the same time in a multilayer DBD. A preliminary processing experiment for polytetrafluoroethylene film has been carried out by adopting homogeneous triplelayer DBD plasma. By testing the water contact angle of the polymer surface before and after the treatment, it was found that hydrophilism of the surface and efficiency of treatment could be effectively improved by the processing of each layer of discharge plasma. [ABSTRACT FROM AUTHOR]

This paper investigates a modular pulsed alternator power system (MPAPS) composed of multiple pairs of counter-rotating alternators. This design provides benefits of torque management, machine manufacturing, current pulse shape flexibility, and fault tolerance, especially in powering long-range railguns. For a practical railgun system powered by MPAPS, one issue is determining the number of modules. Due to the complex nature of pulsed alternators and system, this paper presents a design methodology based on scaling laws of pulsed alternators and system. A variety of physical scaling laws are investigated. The implemented scaling laws are able to predict the system performances as a function of the number of modules including specific energy, alternator temperature, reliability, and efficiency. Finally, taking into account all factors, the proper number of modules is determined. This method can save time and provide the theoretical guideline for the practical design and optimization. [ABSTRACT FROM PUBLISHER]

Brushless doubly-fed alternator (BDFA) has good application prospects in pulsed alternator. It works through the rotor’s pole pairs transformation function to get excitation indirectly. Since there are no brush and slip ring, BDFA is expected to have high reliability and long service life. This paper studies on the excitation control of BDFA in pulse capacitor charge power supply system. A mathematic model of BDFA is established. The power angle characteristic of BDFA and flux changing condition during discharging process is analyzed with this model. Based on the analysis, a novel excitation control theory is proposed. Simulation results are presented to illustrate the performance of this control strategy. [ABSTRACT FROM PUBLISHER]

Based on the urgent needs for modularization and miniaturization of the inductive pulsed power supply system, this paper proposes the conceptual design and comparison of 100-kJ inductive storage power modules including four circuit topologies, three of which are proposed in our previous researches. The four circuit topologies are the STRETCH meat grinder, the XRAM with STRETCH meat grinder unit, the XRAM with strongly coupled inductors, and the XRAM with magnetic flux compression effect. The maximum load current of each constructed module is set to be 50 kA and its pulsewidth is at least 5 ms, which are the same as the main electrical properties of an existing 100-kJ capacitive module. A comparative study on energy density among the constructed inductive modules and the existing capacitive module is carried out in depth. Results show that the inductive modules, considering the volume of semiconductor switches and their control circuits, have higher energy density than that of the capacitive module. Among four constructed inductive modules, the XRAM with strongly coupled inductors module has the highest inductive energy density, and the XRAM with magnetic flux compression effect module has relatively better comprehensive performance. This paper offers the theoretical analysis foundation for investigating the inductive pulse power supply with higher energy. [ABSTRACT FROM PUBLISHER]

The U.S. Naval Research Laboratory is developing a rep-rate charger for a 60-kJ capacitor module. The charger is lithium-ion battery powered and must charge up the capacitive load 50 times over a 5-min period with roughly 1 s between each charge cycle. This paper examines some aspects of the design: lithium-ion battery energy storage, hard switched dc–dc converter, high-voltage rectifier, and capacitive load with pulsed power switching. The lithium-ion batteries are arranged in 12, 16-cell, 50 V modules that are connected in series to form a roughly 600 V prime power supply. A hard switched dc–dc converter with full-bridge rectifier is used to charge the capacitor and a pulse forming network is used to discharge the capacitor into the load. This paper will discuss the system design and available test data. [ABSTRACT FROM PUBLISHER]

Nonlinear transmission lines (NLTLs) are nonlinear LC ladder networks that can act as a nonlinear and dispersive medium, thus allowing the generation of soliton bursts. Several papers have been published indicating that NLTLs offer a new option for pulse shaping and RF generation. In this paper, we investigated the response of an NLTL driven by three different pulse shapes: a rectangular, a half sine, and a triangular waveform. The performance of the NLTL was evaluated through time- and frequency-domain analysis of the RF signal sampled at the 29th section of a 30-section capacitive NLTL. The frequency of the generated RF signal is correlated with the shape of the input signal, whereby the output frequency can be adjusted by the amplitude-time characteristics of the pulse at the input of the capacitive NLTL. Higher frequency oscillations, around 30 MHz, were generated by the rectangular wave train due to its shorter rise time. The propagation of solitons along the NLTL is influenced by the input pulse rise time. Namely, the rectangular pulse showed smaller delay time as it had the shortest rise time (less than 10 ns). Maximum efficiency was obtained for the input pulsewidth of 150 ns under a duty cycle of 1/3 for the three pulse shapes (rectangular, half sine, and triangular), and this combination of parameters yielded the highest RF conversion efficiency of the NLTL. The capacitive NLTL showed a higher RF conversion efficiency (16.4%) when driven by the rectangular input signal. [ABSTRACT FROM AUTHOR]

This paper proposed the use of a ringer, a self-switched inductive storage system, for applications involving reluctance accelerators, a kind of electromagnetic launcher, and compatible with applications where portability is a requirement. There will be shown three different useful approximations for the analysis of the ringer, employed as a power source for a reluctance accelerator. First, it described the equations governing the que behavior of an ideal unloaded ringer, and then the equations for the ringer with an uncoupled inductive load, and ultimately a Lagrangian model for the ringer as an inductive power source for a reluctance accelerator, capable to make predictions about the currents through the circuits and the exit speed of the projectile for a given firing. The accuracy of the predictions made with the third approximation, the Lagrangian model, was tested experimentally. [ABSTRACT FROM AUTHOR]

The vessel’s pulse load can intermittently produce pretty high power in a very short time. Considering their periodical charge-and-discharge process, the system variables of integrated power system (IPS) are characterized by a periodic alternating process rather than a single-equilibrium point. It is not suitable to evaluate the operational performance according to the equilibrium point. In this paper, a periodic orbit model of the IPS and its algorithm is proposed according to sensitivity analysis of end value of system variables to their initial value. The algorithm can be used for distributed compute of system variables, which adjust system variables according to the sensitivity to make the end value equal to the initial value. And, the calculation speed of the algorithm can be increased greatly. The model and the algorithm lay the foundation for assessing the operational performance of the IPS with pulse load. The proposed method has been verified by the simulation test. [ABSTRACT FROM AUTHOR]

This paper discusses a novel methodology to increase the voltage droop compensation range in generalized solid-state bipolar high-voltage Marx modulators with one resonant stage. To maintain the modularity characteristic of bipolar Marx modulators, the imbedding of additional resonant stages is not straightforward. Nevertheless, this paper proposes to add a second resonant stage to the already existing resonant-type voltage droop compensation stage. This second stage increases the voltage droop compensation percentage of a generalized solid-state bipolar Marx generator. The compensation of the bipolar pulse voltage droop is now achieved by adding two auxiliary synchronous compensation resonant voltages, to the output capacitive decaying voltage. Simulation and experimental results are presented for six Marx plus two resonant stages, 16% voltage droop, with 3-kV pulse amplitude, 100- $\mu \text{s}$ pulsewidth, 40-ms relaxation time, and 10-Hz pulse repetition rate. [ABSTRACT FROM AUTHOR]

Propylene carbonate (PC) has a good application prospect in compact pulsed power source as the energy storage medium of pulse forming line. However, its insulation strength is susceptible to impurities, temperature, pressure, and other factors. Hence, it is of great significance to study the effect of temperature on breakdown characteristics of propylene carbonate. In this paper, the effect of temperature on breakdown characteristics of PC was carried out under microsecond pulse. First, pulsed breakdown setup was built. The temperature of PC varied from −50 °C to 50 °C. Breakdown voltages were captured with a capacitive voltage divider and streamer patterns are obtained by ultrahigh-speed cameras. Second, the experimental results are obtained. The breakdown strength of PC increases with increasing temperature. It is 239 kV/cm at −50 °C and rises to 407 kV/cm at 50 °C. At low-temperature breakdown, electron current is more concentrated and breakdown voltage is more stable. Moreover, the energy release for streamer at low temperature is more concentrated, but it is more dispersed for streamer at high temperature. At last, considering the CO2 solubility in PC, PC generates more bubbles and the increase of temperature benefits the release of bubbles at low temperature, resulting in lower breakdown strength. Because of the moisture in PC, breakdown strength of PC falls slightly near 0 °C. Thus, the experimental results are explained by use of stream theory and bubble breakdown theory. PC can adapt to wide-range temperatures, effectively expanding practical applications of the PC in pulsed power source. [ABSTRACT FROM AUTHOR]

The development of pulsed power supplies and switched-mode power supplies raises urgent need for medium-frequency high-power transformers. This paper proposes an optimal design method of medium-frequency Fe-based amorphous transformer based on multiobjective postdecision genetic algorithm. The optimization targets at transformer volume (expressed in terms of area product $A_{p}$) and its loss. Transformer operating frequency $f$ , operating magnetic flux density $B_{m}$ , and current density $J$ are taken as design variables, while temperature rise and efficiency are taken as constraints. This design method helps to solve the traditional transformer’s design problem of repetitive calculation. Moreover, it proposes to the designer a series of optimized transformers, rather than a single solution, so the designer can choose the best transformer according to the application needs. Finally, the simulation and experimental results are presented to validate the effectiveness and feasibility of the theoretical analysis. [ABSTRACT FROM AUTHOR]

This paper presents a new capacitor bank topology for a pulsed power system to improve the efficiency of multistage synchronous induction coilgun. In the proposed method, a switch, such a gate turn-off thyristor, is inserted in parallel to a crowbar diode and load to generate an attractive force between the next stator and the armature. A mathematical model was developed, and finite-element method simulations were conducted to verify the proposed topology. The results show that the proposed method improves the energy efficiency and launch velocity. The improvement in energy efficiency is confirmed from the simulation results of a three-stage synchronous induction coilgun. [ABSTRACT FROM AUTHOR]

This paper studies the erosion of a pair of copper-tungsten alloy (90% mass percent of tungsten) electrodes in a two-electrode spark-gap switch. In the experiment, the switch was operated without cleaning for 20 000 shots (17 160 C transfer charge) at ~0.1 Hz repetition rate. Experimental results indicate that with the increase in number of shots, the cathode presents a severer erosion and there also appears a more serious erosion at the electrode's outer zone than at the central zone. Moreover, erosion features such as protrusions, craters, and cracks at different locations of the surface are quantitatively analyzed and compared. As for erosion products, X-ray photoelectron spectrometer is adopted to analyze the constitutions of the electrode surface. The results reveal an interesting phenomenon regarding the distribution of Cu atom. Initially, the percentage of Cu atom is 24.33%. After 20 000 shots, on the anode surface, the percentages of Cu atom become 13.38%, 26.32%, and 18.75% at the central position, the middle position, and the edge position, respectively. Nevertheless, on the cathode surface, the percentages change to 26.32%, 36.42%, and 39.70%. These results quantitively describe the variations of the electrode during the aging process of a switch, which might be meaningful for electrode erosion research and related applications. [ABSTRACT FROM AUTHOR]

The generation of high-power electromagnetic waves is one of the major applications in the field of highintensity pulsed power. The conventional structure of a pulsed power generator contains a primary energy source and a load separated by a power-amplification system. The latter performs time compression of the slow input energy pulse and delivers a high-intensity power output to the load. Usually, either a Marx generator or a Tesla transformer is used as a power amplifier. In the present case, a system termed "module oscillant utilisant une nouvelle architecture" (MOUNA) uses an innovative and very compact resonant pulsed transformer to drive a dipole antenna. This paper describes the ultracompact multiprimary winding pulsed transformer developed in common by the Université de Pau and Hi Pulse Company that can generate voltage pulses of up to 0.6 MV, with a rise time of less than 270 ns. The transformer design has four primary windings, with two secondary windings in parallel, and a Metglas 2605SA1 amorphous iron magnetic core with an innovative biconic geometry used to optimize the leakage inductance. The overall unit has a weight of 6 kg and a volume of only 3.4 L, and this paper presents in detail its design procedure, with each of the main characteristics being separately analyzed. In particular, simple but accurate analytical calculations of both the leakage inductance and the stray capacitance between the primary and secondary windings are presented and successfully compared with CST-based results. Phenomena such as the core losses and saturation induction are also analyzed. The resonant power-amplifier output characteristics are experimentally studied when attached to a compact capacitive load, coupled to a capacitive voltage probe developed jointly with Loughborough University. Finally, an LTspice-based model of the power ampli- fier is introduced and its predictions are compared with results obtained from a thorough experimental study. [ABSTRACT FROM AUTHOR]

In the rail-type electromagnetic launching system, the equivalent load of pulsed-power supplies (PSs) varies with the launching process, while it has a certain influence on the discharge of pulsed PS. However, in the analysis and design of pulsed PS, researchers usually use the fixed resistance and inductance to simulate the load, which is impossible to accurately study the characteristics of the pulsed PS. The electromagnetic launching needs high-amplitude current pulse. Therefore, in this paper, a mathematical model of electromagnetic launching system driven by multiple superconducting inductive pulsed PS modules is established. In this model, the fixed resistance and inductance load are replaced by the dynamic load model of the railgun; the effects of dynamic load and fixed load on the discharge characteristics are analyzed; the parallel discharge characteristics of multiple high-temperature superconducting pulsed-power transformer (HTSPPT) modules are studied; and the characteristics of the simple rail-type electromagnetic launching driven by multiple HTSPPT modules are analyzed. The simulation results show that a high amplitude of current pulse can be produced using synchronous parallel discharge of multiple HTSPPT modules. The simulation results show that when the resistance and inductance of load are fixed at 2 mΩ and 0.5 µH, respectively, the current amplification factor is 15.666, and the maximum voltage of the auxiliary capacitor is 1079 V. In the dynamic load model, the current amplification factor is 17.174, and the error is 9.6%. The maximum voltage of the auxiliary capacitor is 983 V, and the error is 8.9%. Therefore, the discharge characteristics of pulsed PS can be more accurately studied using dynamic models. [ABSTRACT FROM AUTHOR]

This paper describes a low-cost ignitron-based switching scheme for transferring energy from capacitor bank to various loads, used in plasma physics and other pulsed power applications. Battery-operated driver modules have been designed to simultaneously trigger two ignitrons in parallel by using either transistor-transistor logic pulses or optical pulses using a fiber-optic interface with optical fibers of length up to 50 m, for applications prone to generate electromagnetic interferences. These driver modules are designed using insulated gate bipolar transistors as switches to deliver a pulse of amplitude of ~500 A and rise time of ~1.2 μs to the ignitor-cathode junction of their respective ignitrons. The modules are designed to facilitate triggering of multiple ignitrons required for large current applications. The feasibility of this scheme and the performance of designed circuit are characterized using a test setup. Statistical variation of triggering delay for single ignitrons is studied extensively, and the effect of trigger energy on statistical parameters is reported. Jitters of 63.5 and 85 ns, respectively, have been observed for triggering of each ignitron used in this scheme. Difference in triggering of two ignitrons connected in parallel is also studied, and a jitter of 150 ns is observed in the onset of current discharges through individual ignitrons. [ABSTRACT FROM PUBLISHER]

This paper describes a high-frequency pulsed-power generator for various industrial applications such as water treatment, food and medical apparatus for sterilization, or polluted gas treatment. The system is made of silicon-controlled rectifier as a main trigger switch, capacitors, two-stage magnetic pulse compression stages, and a linear transformer to generate a maximum of 120-kV, 5-kA pulse. The parameters obtained through the development are: output voltage: 120 kV (maximum), pulse repetition ration: 300 pulse per second, pulsewidth: 0.25~\mu \texts , and mean power: 30 kW. The designed pulsed-power generator is confirmed to be used effectively for many high-voltage pulsed-power applications related to environmental industry by simulation and experiments. [ABSTRACT FROM AUTHOR]

This paper presents the design and experimental results of the 36-kW pulsed-power supply for the xenon flash lamp. The continuous conduction mode series-parallel resonant converter is modified. This means that not only the few hundred kilohertz of high switching frequency is introduced to replace the resonant inductor with the leakage inductor of transformer but also the high output current is accomplished by using three-phase delta-connected transformers. In addition, the snubber capacitor of the inverter switches and the power factor correction module is both omitted in the compact structure. Although these main components have changed, the efficiency and power factor of the rated dummy load reach 96% and 0.96%, respectively. Within 36-kW average power, the proposed pulsed-power supply can generate as versatile combination of output pulse. For example, it can generate 20-ms pulse with 1-Hz repetition rate or generate 1-ms pulse with 20-Hz repetition rate. The used insulated gate bipolar transistor is protected from the turn-OFF peak voltage by the snubber circuit, and the effect of the snubber circuit is shown at the actual load condition. [ABSTRACT FROM PUBLISHER]

Slow transfer of energy through capacitive hybrid (STRETCH) meat grinder circuit, which was proposed by the Institute for Advanced Technology, added a capacitor into the traditional meat grinder circuit. Even though its energy density is slightly less than the corresponding pure inductance system, it can reduce the voltage across the opening switch and maintain the high multiplication factor of the opening current. The performance of the STRETCH meat grinder circuit depends on multiple parameters. The inductance ratio ( n=L1 / L2) and the capacitance (C) are the two vital factors, which have a crucial influence on the system performance, such as the voltage over the opening switch ( V_{\rm Sopm}) , the current multiplication factor ( m$ ), and the ratio of the maximum capacitive energy over the total inductive energy ( $\eta )$ . Thorough studies have been carried out in this paper on the relationship between the above two factors and the three performance criteria. This paper also discusses and analyzes the chosen of the key parameters ( $n$ and $C$ ) for a single-stage STRETCH meat grinder with 2-mH total inductance, which is made up of two serial coils with 0.95 coupling factor. The opening current of the main switch is 1 kA, which constitutes a 1-kJ inductive pulsed-power supply. It fully takes the advantage of the STRETCH meat grinder topology, intensifies the study of the inductive pulsed-power supply with higher energies, and is easy to be utilized for practical application. [ABSTRACT FROM PUBLISHER]

As a novel pulsed-power supply, the air-core pulsed alternator is outstanding in providing repetitive pulse with high energy density, and preferred in a variety of fields including laser and electromagnetic launch, etc. To achieve a superior field excitation power supply, the air-core pulsed alternator usually adopts a self-excitation module, putting some emphasis on the design of the excitation conditions. In previous studies, the commutation voltage drop is neglected in excitation condition analysis. However, the voltage drop may have some significant impacts on the excitation conditions, and the neglect would cause a deviation between analysis and practices. This paper focuses on the analysis of excitation condition, taking the commutation voltage drop into account. [ABSTRACT FROM PUBLISHER]

Electromagnetic railgun systems based on capacitive pulsed-power supply (CPPS) have obtained widespread applications because of its obvious advantages over the inductive ones on mature technology, operational reliability, and feasible financial condition. However, the existing CPPS-based electromagnetic railgun system works with low efficiency. In this paper, systematical studies on the CPPS in the synchronously triggered electromagnetic railgun system with constant volume and in the time-delay-triggered electromagnetic railgun system with automatic segmentation are proposed, respectively. In the synchronously triggered electromagnetic railgun system, all pulse-forming units (PFUs) are supposed to be triggered synchronously and the load is simplified as a resistor first. Then, the system performance criteria, i.e., the launch velocity of the armature v \rm end and the system efficiency \eta , are expressed as the function of four independent system variables: 1) the capacitance of each PFU C ; 2) the precharged voltage UC of capacitors; 3) the rail length l ; and 4) the armature mass $m$ . The relationship between \eta $ (or {v}_{\rm end}) and any two independent variables can be found under the environment of MATLAB R2012a by fixing the other two parameters. The results are then verified under the environment of Simplorer 8. These figures can be used to instruct the design of the pulsed-power supply for a designated load or the railgun for a designated source. In the time-delay-triggered electromagnetic railgun system, the principle of automatic segmentation is proposed. According to the segmentation principle, the simulation results under the environment of Simplorer 8 are given for comparison. The paper can provide a theoretical foundation for the future designs to get higher system efficiency. [ABSTRACT FROM PUBLISHER]

Numerous research efforts have been undertaken to improve the feasibility of fielding compact pulsed power systems for a wide variety of applications. Each of these research efforts focuses on specific areas of pulsed power, but few papers have focused on the performance of a grid independent prime power source. This critical component is often overlooked in mobile pulsed power systems. Though not within the pulsed power community, a great deal of work has been performed by those in the electrochemical energy storage community to improve the energy density, power density, working voltage, and cycle life of electrochemical cells. This paper has helped to develop new energy storage technologies for applications such as consumer electronics, electric vehicles, and electrical grid energy storage. However, these electrochemical cells were not developed with pulsed power applications in mind. For that reason, a large amount of research is needed to understand how to effectively use electrochemical cells in pulsed power applications. In this paper, a number of different energy storage chemistries, including lithium-ion batteries, lead acid batteries, and bi-polar nickel metal hydride batteries, have been evaluated for use in pulsed power applications as a result of their high power and energy densities. [ABSTRACT FROM PUBLISHER]

In this paper, a compact circuit topology is presented for pulsed power generation with a semiconductor opening switch (SOS). Such circuits require the generation of a fast forward current through the diode, followed by a reverse current that activates the recovery process. In general, magnetic switches are used to switch the diode current from forward to reverse. Therefore, adjustment of the output voltage of an SOS pulser is difficult. This paper introduces a circuit that allows an adjustable output voltage of the pulser. A solution is realized with a premagnetizing circuit on the primary winding of a pulse transformer (PT), so that a third winding is not needed. The primary capacitor voltage can now be varied while maintaining proper saturation of the PT. [ABSTRACT FROM PUBLISHER]

This paper describes an exploding wire experiment to measure the electrical specific action to melt of structural alloys of copper and aluminum, including C10100, C11000, C18000, C18200, Al6061, and Al7075. These alloys, which are commonly used in railguns and other pulsed power devices, are not produced in fine wire form. Instead of wires, we developed a technique to test macroscopic samples ( 0.25~mm\times 0.5~mm cross section) manufactured with wire electrical discharge machining. This paper includes a description of the design considerations for such macroscopic exploding wire experiments. [ABSTRACT FROM PUBLISHER]

Amorphous magnetic core has been widely used in pulsed power technology with applications including plasma science research, high-power microwave generation, and material surface treatment. For different applications, dynamic properties of the magnetic core will vary with stimulated magnetic field which determines by magnetization time and waveform of the driving voltage. In this paper, toroidal amorphous magnetic core ($\Phi ~540$ – $740\times25$ mm) was investigated theoretically, numerically, and experimentally. Specifically, the circuit is analyzed. A high-voltage test stand, which can generate different driving voltages with same components, was designed and developed in our laboratory. Dynamic properties, including magnetic induction change, coercive force and losses, were studied under three different typical waveforms with the same magnetic flux. Driving voltages of the pulses were 12, 12, and 6 kV and the magnetization rates were 0.6, 1.2, and 0.6 T/ $\mu \text{s}$ , respectively. Experimental results show reasonable agreement with the numerical analysis. [ABSTRACT FROM AUTHOR]

Based on high pulsed power technology, electrical explosion is increasingly utilized to generate shock waves with high pressure. To further magnify the shock wave pressure, we have proposed a novel technique by using energetic materials ignited by the plasma of microsecond wire explosion. Organic derivatives of nitramide, termed nitroamines, are widely used as powerful and relatively insensitive explosives. In this paper, we investigated the shockwave characteristics of nitramine (RDX and HMX) powders ignited by exploding copper wire (diameter 0.3 mm and length 60 mm). With charge voltage of 24 kV and powder mass about 6.0 g, the most evident experimental results suggested that the RDX load possessed higher peak pressure of 11.38 MPa and larger areal impulse of 503.02 MPa $\cdot \mu \text{s}$ , comparing with the shock wave of HMX load (7.22 MPa and 371.28 MPa $\cdot \mu \text{s}$). Moreover, the RDX load also had greater ascent rate of pressure, which was nearly twofold of that of the HMX load. Finally, a simple multi-factor ignition mechanism for nitramine powder under microsecond exploding wire plasma was proposed and discussed. [ABSTRACT FROM AUTHOR]

As the most efficient and compact sources in pulsed power supply for electromagnetic launchers, the air-core pulsed alternator can supply a current as high as 1 MA with a voltage reached several kilovolts. The machine performs various functions, such as kinetic energy storage, electromechanical energy conversion, and power conditioning, making the electromagnetic launch system compact and lightweight. But due to the short history of the machine and the absence of fabrication experience in China, the air-core pulsed alternator is still in an exploratory stage, and there are lots of key technologies and problems needed to be researched deeply. Taking technical risks and manufacturing costs into consideration, a seven-phase air-core pulsed alternator has been proposed and the machine is under development. In this paper, operation principles of the electromagnetic launch system are presented in detail. The mathematical models of the seven-phase alternator and the rail gun are introduced. Based on the mathematical models, a simulation model about the electromagnetic launchers is built, and it is useful to help us figure out the operation characteristic when the self-excitation machine drives the electromagnetic rail gun with a 200-g projectile. As a result, it is convincing by simulation to prove the drive current can be as high as 1 MA and the projectile is with a velocity of 2 km/s at the exit. Simultaneously, violent transient situations will be illustrated in this text, such as the electromagnetic torque and the rotor speed. Meanwhile, simulation results can verify the analytical method and present the current and voltage straightforwardly. They also have great significance on choosing the proper high power switching devices. [ABSTRACT FROM PUBLISHER]

It is important to analyze the electromagnetic coupling characteristics in pulsed power supply (PPS) during the design, and electromagnetic force analysis is becoming more and more important with the development of large capacity and miniaturization of PPS module. In this paper, the magnetic force on the metal structure affected by the pulsed electromagnetic field of the reactor is analyzed and calculated by the means of the finite-element code ANSYS. The results show that the electromagnetic force on the metal structure near the reactor is about ten times that of other parts. The eddy current distribution is calculated by the electromagnetic coupling simulation while the stress on the metal frame is analyzed by the electromagnetic structure coupling simulation. The breaking point assumed to be the weakest point in the structure. The weakest point in the structure is indicated by structural stress simulation. The electromagnetic force is reduced by cutting off the main induce loop through simulation, and the eddy current is measured by experiments. [ABSTRACT FROM PUBLISHER]

Pulsed alternators have the merits of high energy and power densities, which are applied to a wide range of applications, such as the electromagnetic launch, the pulsed laser, and the pulsed high magnetic field. A new type of high-speed and high-frequency pulsed alternator integrating an alternator and a motor, is proposed in this paper. A solid rotor which is made of high-strength alloy steel with high yield strength is used in the pulsed alternator, so it can work at a high tip speed. This machine consists of two alternators and a motor which share one rotor and one field winding. According to different voltage levels and operation frequencies, the motor and the alternators with different stack lengths and pole-pairs are designed, respectively. Therefore, it has the abilities of being driven by low-frequency current and discharging high-frequency pulses. In this paper, the basic structure and fundamental of the pulsed alternator are introduced, the specific parameters of the prototype are given, and the performances are verified by the simulation. The results show that the machine proposed in this paper is suitable for the applications that require high-frequency pulsed discharge. [ABSTRACT FROM PUBLISHER]

Superconducting pulsed-power supply (SPPS) provides an efficient method for both high-density inductive energy storage and high current pulse generation. An SPPS consisting of eight high-temperature superconducting pulsed-power transformer (HTSPPT) modules with XRAM methodology was designed and simulated in preliminary studies. It recycled the leakage flux energy and reduced the voltage across the opening switch with a capacitor in primary. However, the SPPS with XRAM methodology has two problems. The first one is that it can provide high pulse amplitude, but cannot provide enough width. The other one is that the ratio of the maximum capacitive energy over the total inductive energy is relatively large, which cuts down the overall system energy density. This paper proposes a modified topology of SPPS with capacitor reuse methodology. Multiple HTSPPT modules are divided into several groups. Each group shares the same capacitor. The procedure of the modified SPPS is presented in detail. A 270-kJ SPPS with capacitor reuse methodology is designed and simulated to illustrate the modified topology. With the load parameters of a small railgun, the peak value of the load current is 207.15 kA and the pulse half-height width is 5.56 ms, the ratio of the maximum capacitive energy over the total inductive energy is 11%. The characteristics of the modified topology are also described in detail in this paper. [ABSTRACT FROM PUBLISHER]

A new type of metamaterial has been developed for the use in pulsed power systems. These materials have the applications in high-power microwave systems, dielectric-loaded components, and nonlinear transmission lines. We present a double-positive metamaterial created by incorporating several types of nickel–zinc ferrite powders into a silane binder. Measurements show these materials to possess positive relative permeability and permittivity values in the range of 3–6 for frequencies between 20 MHz and 2 GHz. The dielectric strengths of five different types of ferrite-based composites were measured to evaluate the potential of these materials for high-power applications. A pulse with a magnitude up to 100 kV and rise time on the order of tens of nanoseconds was used to determine the dielectric strength of disks with a diameter of 2.54 cm and a thickness of 0.2 cm. A maximum electric field of 163.79 kV/cm was sustained before breakdown. This paper presents a statistical analysis of the dielectric strength data and projects the power handling capabilities of the composites. [ABSTRACT FROM AUTHOR]

We are studying the treatment method that injects the droplets of waste water into pulsed discharge plasma generating by a pulsed power technology as an advanced water treatment technique. The active species, such as ozone and OH radical that have high oxidizing power, are generated in the place injecting the droplets by the discharge, and can be effectively used to decompose the organic compounds that are difficult to decompose. However, there has been few investigation of interaction between the pulse streamer discharge and the droplet in a configuration of a treatment reactor. In addition, a propagation route of pulse streamer discharge has been few investigated in the space putting the droplets in the configuration of the treatment reactor. In this paper, the propagation route of the pulse streamer discharge in the space with the droplets of water has been investigated at the configuration using the wire electrode. In addition, the influence of the droplets to the discharge has been investigated. From results, it was shown that the pulse streamer discharge propagated on the surface of the droplet. Primary streamers mainly occurred at the positions of the droplets. The propagation lengths of secondary streamer in air with the droplets were shorter than that without the droplets. The existence of the droplets prevents the propagation of the secondary streamer. [ABSTRACT FROM AUTHOR]