Pulsed Power Generator Research Articles

Development of inductive energy storage pulsed power supply using SiC semiconductor devices for ozone production by streamer discharges

Abstract Inductive energy storage (IES) pulsed power generator driven by the silicon carbide (SiC)-MOSFET with the blocking voltage of 1.2 kV was developed. The IES pulsed power generator consists of a capacitor, a pulsed transformer and the SiC-MOSFET used as an opening switch. The influence of turn ratio of the pulsed transformer on the output voltage was evaluated. The amplitude of output voltage increased with increasing the secondary turn ratio. Under the conditions of no lord , a peak output voltage of 13 kV and a pulse width of 120 ns were obtained with a voltage across the drain-source terminals of the MOSFET of 1kV with no lord. The peak voltage value increased, and the peak current and pulse width value decreased with increasing load resistance and decreased capacitance. The maximum energy transfer efficiency was obtained with 500 Ω and was Approximately 56%.

1 kHz, 5.3 kW peak power pulse generation from a LiNbO3 acousto-optically Q-switched Er:YAP laser

In this paper, we present, for the first time, a bulk LiNbO3 (LN) acousto-optic (AO) Q-switched Er:YAP laser operating at a pulse repetition frequency (PRF) of 1 kHz. At this frequency, the laser achieves a maximum single pulse energy of 0.34 mJ, with a corresponding pulse duration of 64.5 ns and a peak power of 5.3 kW. Additionally, we characterize the laser beam quality factors, Mx2 = 2.7 and My2 = 2.5, and its central wavelength at 2730.7 nm, all at 1 kHz. These results highlight the significant potential of LN AO Q-switched Er:YAP lasers for enhancing mid-infrared laser applications.

A novel racetrack Blumlein pulse forming line.

Pulse forming lines (PFL) are widely applied in high-power pulsed power generators due to their high energy density and great ability with square waveform modulation. However, the three-cylinder coaxial Blumlein line (tPFL), a commonly used PFL structure, has low energy efficiency due to the difference in impedance of the outer and inner lines. In order to increase the outer line impedance and improve the output waveform of the PFL, a racetrack Blumlein pulse forming line (r-B PFL), formed by two inner cylinders, two middle cylinders, and one outer cylinder that resembles a runway shape, is proposed in this paper. The glycerin energy storage technology and the spiral line technology were applied in the PFL. Moreover, the r-B PFL was tested experimentally after its construction, yielding a satisfactory result. The PFL structure in which multiple middle cylinders share the same outer cylinder achieves a higher outer line impedance, leading to a high energy efficiency of the PFL, which contributes to the PFL development trend toward compactness and miniaturization.

Structure and dynamics of magneto-inertial, differentially rotating laboratory plasmas

We present a detailed characterization of the structure and evolution of differentially rotating plasmas driven on the MAGPIE pulsed-power generator (1.4 MA peak current, 240 ns rise time). The experiments were designed to simulate physics relevant to accretion discs and jets on laboratory scales. A cylindrical aluminium wire array Z pinch enclosed by return posts with an overall azimuthal off-set angle was driven to produce ablation plasma flows that propagate inwards in a slightly off-radial trajectory, injecting mass, angular momentum and confining ram pressure to a rotating plasma column on the axis. However, the plasma is free to expand axially, forming a collimated, differentially rotating axial jet that propagates at ${\approx }100\,{\rm km}\,{\rm s}^{-1}$ . The density profile of the jet corresponds to a dense shell surrounding a low-density core, which is consistent with the centrifugal barrier effect being sustained along the jet's propagation. We show analytically that, as the rotating plasma accretes mass, conservation of mass and momentum implies plasma radial growth scaling as $r \propto t^{1/3}$ . As the characteristic moment of inertia increases, the rotation velocity is predicted to decrease and settle on a characteristic value ${\approx }20\,{\rm km}\,{\rm s}^{-1}$ . We find that both predictions are in agreement with Thomson scattering and optical self-emission imaging measurements.

DENNIS: a design and analysis tool for dynamic material x-ray diffraction experiments

We present DENNIS (Diffraction Experiment desigN and aNalysiS): a graphical software tool useful for the design and analysis of dynamic x-ray diffraction experiments, such as those performed on the Z Pulsed Power Facility, Thor Pulsed Power Generator, and Dynamic Compression Sector (DCS) of the Advanced Photon Source. DENNIS provides rapid powder and single-crystal diffraction pattern predictions and powder diffraction pattern image integration in three-dimensional geometries. Additional features include crystallographic information file reading, image processing, and synthetic diffraction pattern image generation. We overview the software's capabilities, detail the prediction and integration methodologies, and provide example implementations on Z and DCS experiments.

Collaborative Design of Pulsed-Power Generator Based on SiC Drift Step Recovery Diode

Collaborative Design of Pulsed-Power Generator Based on SiC Drift Step Recovery Diode

A solid-state pulse power sub-nanosecond SiC DSRD-based generator with high-voltage and high repetition frequency for pulse discharge water treatment

Water treatment is one of the most important issues for all walks of life around the world. The unique advantages of the solid-state power electronic pulses in water treatment make it attractive and promising in practical applications. The output voltage, rising time, repetition rate, and peak power of output pulses have a significant impact on the effectiveness of water treatment. Especially in pulse electric field treatment and pulse discharge treatment, the pulse with fast rising time achieves the advantage of generating plasma without corona, which can avoid water heating effect and greatly improve the efficiency of the pulse generator. High repetition rate can significantly reduce the peak power requirement of the pulse in water treatment application, making the equipment smaller and improving the power density. Therefore, the study developed a high-voltage high frequency sub-nanosecond pulse power generator (PPG) system for wastewater treatment. It adopts SiC DSRD (Drift Step Recovery Diode) solid-state switches and realize modular design, which can achieve high performance and can be flexible expanded according to the requirements of water treatment capacity. Finally, an expandable high-voltage PPG for water treatment is built. The output parameters of the PPG include output pulse voltage range from 1 to 5.28 kV, rise time <600 ps (20%–90%), repetition up to 1 MHz. The experiment results of PPG application for pulse discharge water treatment is presented. The results indicate that the proposed generator achieves high-efficiency degradation of 4-Chlorophenol (4-CP), which is one of the most common chlorophenol compounds in wastewater. From experiment, the homemade system can degrade 450 mL waste water containing 500 mg/L 4-CP in 35 min, with a degradation rate of 98%. Thereby, the requirement for electric field intensity decreased. Through the further quantitative analysis, the impact of frequency, voltage, and electrode spacing on the degradation effect of 4-CP is confirmed.

Ultrahigh energy efficiency from a supersonic underwater ultrasound source

The present work is dedicated to an experimental and theoretical study of an innovative underwater ultrasound source. The source works using a technique in which a pulsed power generator using the impedance mismatch of a long high-voltage coaxial cable generates a train of voltage impulses with a very high pulse repetition frequency of the order of a few MHz. Applying this train of voltage impulses to a pair of underwater electrodes generates a streamer-initiated breakdown of water and, subsequently, a plasma column connecting the electrodes over a very large inter-electrode gap of 55 mm. The interaction of the long plasma column thus formed with the surrounding water produces a rapidly expanding vapor bubble, an “instrument” producing a strong pressure wave with an overall energy efficiency of 24%, an order of magnitude higher than most underwater pressure sources reported in the literature.

Dynamic characteristics of a coaxial magnetic switch modulating pulse forming networks.

Pulsed power generators utilizing magnetic switch technology within the 100ns scale have become widespread for surface treatment, high power microwave generation, and food processing, in which the dynamic characteristics of the magnetic switch perform an important function. The saturation process, electric field between layers, and energy loss are closely associated with the applied time scale of the magnetic core, which affects the dynamic characteristics of the switch. However, compared with the study within the microsecond scale, the dynamic characteristics of magnetic switches within the 100ns scale have not been studied in depth. In this paper, the dynamic characteristics of a coaxial magnetic switch modulating pulse forming networks (PFNs) are studied via both field-loop co-simulation and scaled experimental test. It is found that increasing PFN section number (Ns) leads to an acceleration in the saturation process of the core, which helps understand the switch performance of the magnetic core more clearly. With respect to a specific magnetic switch based on a ferromagnetic core, it is quantitatively analyzed that increasing Ns from 1 to 10 leads to a 16.1% reduction in core saturation time (tsat), a 13.4% increase in eddy loss (EET), and a 5.7% rise in maximum interlamination field strength (Emax) under the 100ns scale; however, tsat is reduced by 19.3%, EET increases by 5.2%, and Emax rises by 2.3% under the microsecond scale. The results could provide a design reference for magnetic switches in pulsed power generators.

Electroporation of Chlorella vulgaris with laboratory devices capable of generating arbitrary waveform pulses

The influence of pulsed electric fields with different waveforms on the electroporation of Chlorella vulgaris was investigated in this research. A pulsed power generator that can produce high-voltage pulses with arbitrary waveforms was developed. This device was utilized to generate pulsed electric fields of nine different waveforms (rectangle, bipolar rectangle, sine, half-sine, exponential decay, exponential increase, oscillation superimposed on rectangle, two-step rectangle, and triangle) with the same amplitude (17.5 kV/cm) and energy (0.27 J/pulse) for the electroporation of Chlorella vulgaris. The results showed that the pulse waveform played a significant role in the electroporation, which could be explained by the duration of transmembrane potential above threshold Δφth and by the frequent and rapid changes in the electric field above threshold Eth. Among the nine pulses, the oscillating superimposed rectangular pulse and half-sinusoidal pulse had the highest electroporation rate, with an improvement of about 40% compared to the conventional rectangular pulse.

A high‐power electromagnetic source for disabling improvised explosive devices

AbstractUltra‐wideband (UWB) microwave sources driven by specialised pulsed power generators have experienced a considerable development in the last decade due to their wide domain of new applications such as defence or counter‐terrorism activity. The authors present the main findings of a research dedicated to the development of a pulsed power‐driven electromagnetic field source for disabling improvised explosive devices (IED). The pulsed power generator driving the source is a 13‐stage compact Marx producing voltage pulses reaching an amplitude of 0.5 MV, with a pulse repetition frequency (PRF) of up to 100 Hz. The generator is coupled to a bipolar pulse forming line, providing bipolar pulses with a dV/dt of around 1.6 MV/ns. This pulsed power system feeds an array composed of 16 Koshelev‐type UWB antennas through an impedance matching transformer. The resulting electromagnetic source is capable to produce pulsed electric fields (PEFs) having a figure‐of‐merit (FOM) of 1 MV. First, practical experiments were carried out to study the effects of the PEFs on targets. The targets used in the present study are M2B type flashbulbs, known to have the same susceptibility as the US army M6 detonator. Different configurations of wires (shielded, twisted, etc) with different lengths were used in connecting items inside these targets. The tests were performed by placing the flashbulbs at different distances to determine the essential parameters (i.e., amplitude, duration, and frequency range) of the PEFs required to trigger them. An overview of the experimental campaign and the main findings are also presented followed by conclusions.

Review of High Voltage Pulsed Power Supplies and Power Electronics in Pulse Power Generation

Recently, pulse-shaped power supplies have become more popular. Pulsed power is versatile and useful as a supply method since it can take several shapes and has many pulse characteristics. The release of electrons, protons, and neutrons from an atom and the synthesis of molecules to generate ions or other molecules require a lot of immediate energy. Pulsed power is needed for decomposition, molecular fusion and material joining, radiation generation (e.g., electrons, lasers, radar), explosive processes for concrete recycling, wastewater and exhaust gas treatment, and material surface treatments. Industrial and environmental applications require pulsed power, which requires efficient and adaptive pulse modulators. Higher-quality repeating pulses are needed for plasma fusion and laser weapons. Marx Generators, Magnetic Pulse Compressors, Pulse Forming Networks, and Multistage Blumlein Lines have several uses. Pulse modulators use spark gap and hydrogen thyratron gas/magnetic switching technologies for their high voltage tolerance and low-rise times. These creatures are inefficient, unreliable, repetitious, and short-lived. These devices are heavy, bulky, and expensive. Solid-state switching technology can replace conventional devices, improving pulse supply. High-frequency switching repeats the pulsed power supply. These items are compact, efficient, affordable, reliable, and durable. Solid-state transistor applications may not meet switch voltage ratings and rise time constraints. Various power electronics configurations can produce solid-state high-voltage pulses.

SPH code development for X-pinch plasma simulation

We have developed the first smoothed particle hydrodynamics code for investigating X-pinch plasmas driven by pulsed power generators. To achieve the required code performance, we incorporated and discussed appropriate physics models capable of simulating the X-pinch phenomenon across various domains, encompassing equation of state, plasma transport, and radiation effects. The simulations were conducted in full three dimensions using our newly developed code, and we have compared and evaluated the results with experimental data obtained from the X-pinch device at Seoul National University. As a result, our simulations effectively captured the implosion behavior of X-pinch plasma, faithfully reproducing the four-step evolution process commonly observed in typical X-pinch configurations. Furthermore, it provided comprehensive spatiotemporal data on various plasma parameters, including density, temperature, velocity field, and radiated power. Notably, the electron temperature and density at the hot spot well agree with the experimental measurements, validating the accuracy and reliability of the developed simulation code. Additionally, the radiation data exhibited significantly improved accuracy compared to previous simulation results, confirming the effectiveness of the proposed radiation model, and it provides valuable insights into the X-pinch hot spot formation.

Terahertz super-radiance from picosecond electron bunches moving through a micro-undulator

We suggest using emission from the photoinjector-formed electron bunches moving through micro-undulators for generation of powerful super-radiant pulses in the terahertz/far infrared frequency range. Within the time-domain quasi-optical approach, we demonstrate the spatial coherence of emission with narrow angular spectrum from the electron bunches with transverse size limited by the Fresnel parameter NF ∼ 1, when the diffraction effects together with slippage provide synchronization of radiation from the entire volume of the extended bunch. For picosecond-duration, 5 MeV, 250 pC electron bunches, and a micro-undulator with a period of 3 mm, the peak power of 15 THz SR pulses can be about of 20 MW.

Moderate electric field driven ultrahigh energy density in BiFeO3–BaTiO3–based ceramics with improved relaxor behavior and breakdown strength

Dielectric ceramic–based capacitors have triggered growing concerns because of their potential applications in next–generation pulsed power electronic devices. However, the low energy density seriously hampers their further development, and the high energy density (>6 J/cm3) is generally realized under a giant external electric field (>500 kV/cm). Herein, an ultrahigh recoverable energy density of 8.5 J/cm3 and a high efficiency of 87 % under a moderate electric field of 470 kV/cm is obtained in the Sr(Sc1/2Nb1/2)O3 modified BiFeO3–BaTiO3 ceramics via the improved dielectric relaxation and electric breakdown strength (Eb). And the promoted band gap and reduced grain size play a key role in enhancing Eb. Moreover, the sample with the optimal composition also exhibits superb thermal reliability at a wide temperature range, and outstanding frequency and cycling stability under 350 kV/cm. This work not only provides a hopeful alternative for advanced energy storage capacitors, but also demonstrates an effective way to explore high–performance dielectric materials.

Generation of powerful short microwave pulses using an amplifier on GaN transistors

Generation of powerful short microwave pulses using an amplifier on GaN transistors

Synergistically Optimizing Pressure-Driven Energy Conversion and Energy-Harvesting Application via Modulating an Antiferroelectric-to-Ferroelectric Overlap Zone in Antiferroelectric Ceramics.

Dielectric ceramics with ultrahigh polarization and energy density are the core components used in next-generation pulse power generators based on explosive energy conversion. However, the low polarization of ferroelectric materials and high depolarized pressure hinder their development toward miniaturization, light weight, and integration, while antiferroelectric materials possessing larger nonlinear saturated polarization and rich phase structure are neglected in pulse power energy conversion. Here, an effective strategy of constructing antiferroelectric-to-ferroelectric overlap zone is achieved in binary system (1 - x)(Pb,La)(Zr,Ti)O3-xBa(Al1/2Nb1/2)O3 antiferroelectric ceramics to realize an excellent polarization of 41 μC/cm2 and a large depolarization efficiency of >99% under 150 MPa as well as a record high energy harvesting density of 2.5 J/cm3 under 400 MPa. The excellent comprehensive energy conversion and energy harvesting performance is mainly attributed to the strategy of antiferroelectric-to-ferroelectric overlap zone and improved microdomain density, at which orthorhombic-to-rhombohedral structure evolution is confirmed by transmission electron microscopy, piezo-response force microscopy, and Raman spectrum, resulting in substantially enhanced remanent polarization compared to ferroelectric ceramics. Besides, excellent temperature stability (∼180 °C) and optimized depolarization pressure also support that this binary system is a candidate for energy conversion and energy harvesting application. This work demonstrates that antiferroelectric-to-ferroelectric overlap based on antiferroelectric materials is an excellent strategy to develop dielectric materials with excellent depolarized polarization and energy harvesting density for energy conversion and harvesting.

Antiferroelectric Lead based Perovskite Material properties andapplications: A Review

In this review paper, the discussion is about some of the lead based antiferroelectric (AFE) perovskite materials. The antiferroelectric perovskite materials mainly lead zirconate (PZ) and lead zirconate titanate (PZT) prepared by solid state reaction route with their structure change at different concentrations, phase transition, their dielectric properties ormore. These materials caught the attention of the researchers because of their use in high energy storage devices, pyroelectric devices, sensors, cooling devices, pulse power generators and have many more applications. The reason could be their electric field phase transformation between the antiferroelectric (AFE) state and ferroelectric (FE) state and the phase switching property can be one of the strong factors responsible for the performance of the PZ based materials. Thecentral focus of this review is to briefly explain the continuous increase in research in the antiferroelectric materials by enhancing the PZ with many dopants. We mainly address PZ and PZT solid solution properties.

Серия ОВП-импульсов подземных вод побережья Байкала 20–27 марта 2024 г.: вероятная связь с магнитными бурями

A short (8-day) series of ORP pulses begins with low-amplitude (about 1 mV) oscillations, partially smoothes out, and progresses to deep minima reaching 138 mV. The series differs from the pulses covering the full (30-day) tidal lunar-solar cycle in February–early March 2024. It is suggested that variations in ORP pulses are temporally related to magnetic storms. Also, for generation of powerful ORP pulses, the spring lunar-solar tide is considered as a favorable factor. The March series of pulses is accompanied by decreasing background ORP values. Similar ORP decrease, but without pulses, characterizes the January episodes of earthquakes in the central Baikal Rift System.

Analysis and Design of a Pulsed Power Generator for a Low-Energy Magnetic Pulse Welding System

Magnetic pulse welding (MPW) is a joining method that uses Lorentz force generated from an electromagnetic field. This method not only has the advantage of not causing thermal deformation of the material and no by-products compared to the method of joining by melting by heat but also enables the joining of dissimilar metals rather than the joining of the same metal. Joining dissimilar metals can reduce the weight of mechanical devices and apply them to various fields. Recent research on MPW has focused on the characteristics of bonding according to the material or structure of metal rather than on pulse power research that generates the main factor of operation. However, in the operation of MPW, a Lorentz force is generated by the induced current caused by the electromotive force created in the flyer tube and the external magnetic field in the actuator. Therefore, it is necessary to analyze and optimize the pulse power to improve reliability and to miniaturize the system to expand the MPW utilization range. In this paper, we analyzed MPW operation according to a section of the pulse power output waveform. A condition for obtaining the maximum current in the flyer tube was proposed, and a plateau-shaped waveform was derived as an ideal output waveform capable of maintaining the Lorentz force. Through analysis, the proposed pulse power device is designed as a pulse-forming network (PFN) that generates a plateau output waveform. The design specification is that the circuit of PFN (type E) is designed so that the output waveform is pulse width 10 (μs) and the maximum output current is 100 (kA), and it is verified by simulation.