Showing papers on "Marx generator published in 2021"

A Compact Modular 5 GW Pulse PFN-Marx Generator for Driving HPM Source

Abstract: A compact and modular pulse forming network (PFN)-Marx generator with output parameters of 5 GW, 500 kV, and 30 Hz repetition is designed and constructed to produce intense electron beams for the purpose of high-power microwave (HPM) generation in the paper. The PFN-Marx is composed by 22 stages of PFN modules, and each module is formed by three mica capacitors (6 nF/50 kV) connected in parallel. Benefiting from the utilization of mica capacitors with high energy density and a mini-trigger source integrated into the magnetic transformer and the magnetic switch, the compactness of the PFN-Marx system is improved significantly. The structure of the PFN module, the gas switch unit, and the connection between PFN modules and switches are well designed for modular realization. Experimental results show that this generator can deliver electrical pulses with the pulse width of 100 ns and amplitude of 500 kV on a 59-ohm water load at a repetition rate of 30 Hz in burst mode. The PFN-Marx generator is fitted into a cuboid stainless steel case with the length of 80 cm. The ratio of storage energy to volume and the ratio of power to weight of the PFN-Marx generator are calculated to be 6.5 J/L and 90 MW/kg, respectively. Furthermore, utilizing the generator to drive the transit time oscillator (TTO) at a voltage level of 450 kV, a 100 MW microwave pulse with the pulse width of 20 ns is generated.

High voltage nanosecond pulse generator based on avalanche transistor Marx bank circuit and linear transformer driver.

Abstract: Avalanche transistor Marx bank circuits (MBCs) are widely used in high voltage repetitive nanosecond pulse generators, but problems exist with respect to increasing the output voltage due to the limited pulsed current. Accordingly, a novel topology based on an avalanche transistor MBC combined with a linear transformer driver is proposed, the latter of which exhibits advantageous stress distribution and modular structure. A four-module prototype with four units in each module is developed in the laboratory. The output characteristics are investigated by varying important parameters such as the main capacitance, the number of conducting units, the number of cascaded modules, and the trigger signal time delay. The test results verify the validity of the proposed topology. For a 50 Ω resistive load, the prototype can generate pulses with an amplitude of 10.9 kV, a rise time of 3.3 ns, and a voltage superposition efficiency of 89%. The topology proposed in this paper may help to provide a method to further improve the output performance of avalanche transistor MBCs.

Improved Auxiliary Triggering Topology for High-Power Nanosecond Pulse Generators Based on Avalanche Transistors

Abstract: The avalanche transistor-based Marx circuit has great advantages in generating high-voltage nanosecond pulses. The introduction of auxiliary triggering topology (ATT) can reduce the damage probability of transistors in M × N -stage Marx bank circuits (MBCs). However, as the number of modified stages increases, the output voltage drops significantly, which makes it not achievable to adopt ATT at each stage. The transistors in nonmodified stages still have a certain failure rate when operating at a high repetition rate. Moreover, the previous ATT is only applicable in the negative polarity MBC. In this article, an improved ATT is proposed to solve the above problems. First, its operating principle is analyzed, and the feasibility of its application in both negative and positive MBCs is verified by simulations. Then, the effects of the improved ATT on M × N -stage MBCs are experimentally studied, and the results show that the improved ATT can be used in all stages of MBC without reducing the output voltage. It can also reduce the minimum operating voltage of transistors and widen the regulating range of output voltage. In addition, it can improve the synchronous conduction of parallel-connected transistors. Finally, two nanosecond pulse generators with positive and negative polarity, respectively, are developed and used to drive the atmospheric pressure plasma jet. The amplitude of output voltage can be adjusted in the range of 5–10 kV, measuring at the open end of a coaxial cable with 75 Ω impedance, and the maximum repetition rate is up to 7 kHz.

Portable DC Supply Based on SiC Power Devices for High-Voltage Marx Generator

Abstract: The paper describes major issues related to the design of a portable SiC-based DC supply developed for evaluation of a high-voltage Marx generator. This generator is developed to be a part of an electromagnetic cannon providing very high voltage and current pulses aiming at the destruction of electronics equipment in a specific area. The portable DC supply offers a very high voltage gain: input voltage is 24 V, while the generator requires supply voltages up to 50 kV. Thus, the system contains two stages designed on the basis of SiC power devices operating with frequencies up to 100 kHz. At first, the input voltage is boosted up to 400 V by a non-isolated double-boost converter, and then a resonant DC-DC converter with a special transformer elevates the voltage to the required level. In the paper, the main components of the laboratory setup are presented, and experimental results of the DC supply and whole system are also shown.

Multichannel Plasma Synthetic Jet Actuator Driven by Marx High-Voltage Generator

Abstract: The plasma synthetic jet (PSJ) is a high-energy synthetic jet that is excited by gas spark discharging plasma in an active flow-control area. Because achieving large-scale flow-control applications...

Development of a High Peak Voltage Picoseconds Avalanche Transistor Based Marx Bank Circuit

Abstract: Avalanche transistor-based Marx bank circuit (MBC) is widely used to generate high voltage nanosecond pulses with high amplitude, high repetition rate, fast rise time, and low jitter. Researchers have tried to modify the circuit structure by using parallel or series avalanche transistors to increase peak power. However, in this work, the detailed process of analyzing and designing a compact Marx generator using avalanche transistors will be described. The purpose of this article is to report our experimental observations on the mechanism of operation of the MBCs. By studying the influence of amplitude and pulse width of the trigger circuit, a Gaussian pulse with a rising edge of 160 ps, full width at half maximum (FWHM) of 660 ps, and amplitude of 5000 V are obtained. The design improves the output voltage and pulse repetition frequency (PRF) effectively while reducing the use of the number of transistors. Based on the conventional principles of avalanche transistors and Marx circuit, a list of useful and interesting conclusions obtained from experiments will be reported.

A Semi-Analytic Approach for Determining Marx Generator Optimum Setup During Power Transformers Factory Test

Abstract: Finding the optimum parameters of the Marx generator during the power transformers factory test to attain a standard lightning impulse (LI) wave shape is usually done by a try and error procedure. To avoid this time consuming process, a new analytic method is introduced in this paper. In this method, the frequency response of the transformer is measured at first. Then, a semi-analytic approach is utilized to attain a proper structure of the transformer's impedance model and subsequently its parameters are simply obtained by solving an optimization problem. Afterwards, by employing the equivalent model of the LI test circuit, an analytic method is proposed to select the Marx generator's parameters to achieve the desired predefined characteristics of the LI wave shape. The proposed approach has the ability to make the whole procedure automatic which makes it fast and cost-effective. Finally, by performing some experimental tests using a real 12 stage high voltage Marx generator, the efficiency of the proposed method is investigated.

Solid-State Marx Generator Circuit With Inductive Booster

Abstract: We have modified a solid-state Marx generator by inserting inductors into the circuit so that the inductive energy can boost the output voltage to a level several times as high as $n \times V_{0}$ , where $n$ is the number of Marx stages and $V_{0}$ is the charging voltage of each stage. Switches in the Marx generator are properly controlled allowing certain energy transfer from the capacitors to the inductors before the output begins. As a result, when all capacitors and inductors are connected in series, the voltage generated on the load is from both capacitive energy storage and inductive energy storage. In the demonstration experiment, we have used a 4-stage Marx circuit to generate an output voltage with a peak value of ~ 9 kV on a 400- $\Omega $ load, with a charging voltage of 800 V.

Auxiliary Power Supply for a Semiconductor-based Marx Generator

Abstract: An auxiliary power supply for stages of a semiconductor-based Marx generator has been designed and tested. The auxiliary power supply converts the Marx generator's stage voltage ranging from 50 V to 1000 V to stabilized voltages of 7 V and 18 V at a total output power of up to 1.5 W. It comprises a transformer for insulation between input and both outputs and features a flyback converter design. The on-time of the MOSFET switch has been designed to vary between approximately 1 µs and 20 µs depending on the generator's stage voltage. The power supply has been tested successfully in an 8-stage Marx generator.

Modular Marx Generator Based on SiC-MOSFET Generating Adjustable Rectangular Pulses

Abstract: The paper introduces a new design of Marx generator based on modular stages using Silicon Carbide MOSFETs (SiC-MOSFET) aimed to be used in biomedical applications. In this process, living cells are treated with intense nanosecond Pulsed Electrical Field (nsPEF). The electric field dose should be controlled by adjusting the pulse parameters such as amplitude, repetition rate and pulse-width. For this purpose, the structure of the proposed generator enables negative pulses with a quasi-rectangular shape, controllable amplitude, pulse-width and repetition-rate. A complete simulation study was conducted in ANSYS-Simplorer to verify the overall performance. A compact, modular prototype of Marx generator was designed with 1.7 kV rated SiC-MOSFETs and, finally, a set of experiments confirmed all expected features.

A durable microsecond solid-state pulsed power system

Abstract: An all-solid-state microsecond pulsed power system has been tested in this paper. It can produce larger than 50 kV and microsecond-range pulses continuously for more than 9 × 104 shots into a resistive load at a repetition rate of 10 pps. The whole device has accumulatively operated more than 15 000 pulses at 100 Hz and 3 × 105 pulses at 10 Hz. This all-solid-state pulsed power system consists of a repetitive power supply, a four-stage Marx generator, a pulse forming network, and a resistive load. The repetitive power supply of the pulsed power system is calculated and analyzed first, followed by the introduction of the Marx generator and the three-section anti-resonance network. A polymer box of sodium chloride solution is applied as a resistive load with an impedance of 200 Ω. Repetitive experiments showed that this system is able to operate stably at 100 Hz repetition rate without failure.

Development of a Test Bench for the Investigation of the Breakdown Voltage of Insulation Materials at Medium Frequency Rectangular Voltages

Abstract: The increased power and voltage ratings of semiconductors fosters the use in medium voltage components, such as ac–dc converters. With a bipolar medium frequent rectangular (MF RECT) voltage, the converter size can be reduced and the efficiency increased. Possible insulating materials for medium voltage transformers are oil and insulation paper. The breakdown voltage of insulation materials is depending on the frequency and the shape of the voltage curve. Until today, only a few investigations of the breakdown voltage of insulating materials at sinusoidal and RECT voltages up to a few tens of kilohertz have been published. To design and optimize MF transformers at RECT voltages, further investigations are necessary. Therefore, a test bench for measuring the breakdown voltage at RECT voltages in the frequency range between one and ten kilohertz up to several tens of kilovolts is developed. The test bench is inspired by a Marx generator, which is a high voltage source for impulse voltages. By substituting resistances and spark gaps by IGBTs and adding galvanically insulated power sources, a medium frequent bipolar voltage can be generated. The test bench is characterized with respect to slew rate, input power, frequency, and voltage amplitude. Its usability is shown in first breakdown voltage measurements of insulation papers, used for transformer insulation.

Investigation and Evaluation of Solid-State Marx Pulse Generator Based on 3-D Busbar

Abstract: SiC-MOSFET has been widely used in nanosecond pulse power generators due to its excellent switching characteristics. The solid-state Marx generator using SiC-MOSFET has the advantages of modularity, flexible adjustment, and economic reliability. However, due to the limitation of the busbar loop’s parasitic inductance, the excellent switching characteristics of SiC-MOSFETs have not yet been fully utilized in solid-state Marx. This article discusses the PCB wiring structure of the single-module of solid-state Marx and the influence of its superimposed spatial distribution parameters on the output pulse waveform. The principle of 3-D busbar structure and mutual inductance cancellation method to reduce the parasitic inductance of pulse busbar loop is proposed. And verify the above principle through electromagnetic simulation and four-stage superposition experiment. The parasitic inductance of the busbar loop is less than 4 nH. The voltage edge of the output pulse is further reduced, the current rise/fall speed is increased by about 2.3 times, and the switching voltage overshoot is reduced by 80%. And the proposed structure effectively suppresses the gate bounce and improves the solid-state Marx pulse characteristics. Finally, the stability and reliability of the system are improved too.

Design and Application of Repetitive Nanosecond Pulse Generator Based on Avalanche Transistors

Abstract: In this paper, two 4×10-stage Marx bank circuits based on avalanche transistors were designed. Both circuits can produce nanosecond pulses with an amplitude of 10 kV and a rise time less than 4 ns, one of which generated positive pulses and the other generated negative pulses. Both circuits were improved by using the auxiliary trigger topology (ATT) which can change from over-voltage conduction to the combined action of over-voltage and trigger. And the result showed that the use of ATT decreased the failure rate of transistor. And then, an APPJ generating device with a pin-ring structure was built. The effects of pulse polarity, repetition rate, and flow rate of Helium on the characteristics of APPJ were experimentally studied. The results showed that under the same conditions, the length of APPJ generated by the positive pulse was longer than negative pulses. The discharge repetition rates only affected the brightness of APPJ, and the higher the repetition frequency, the greater the brightness. As the flow rate increased, the length of APPJ appeared to increase first and then decrease.

A New Modular Structure of Marx Generator Based on Interleaved Boost Converter Operating in Discontinuous Conduction Mode

Abstract: In this article, a new modular structure of Marx generators (MGs) based on interleaved boost converter is proposed. The converter operates in discontinuous conduction mode to generate a high-voltage pulsed power with a common low-voltage source. Unlimited stages can be added to the proposed structure to reach lower maximum voltage stress for the semiconductors or to generate several kilovolts of the output pulses, while the voltage of the semiconductors remains constant. This structure resulted in a higher pulse repetition rate, fewer semiconductor elements, and lower semiconductor voltage stress in comparison to conventional MGs. Hence, the proposed structure is applicable for and efficient in supplying plasma applications with high-voltage pulses. The theoretical foundation of the introduced converter is presented and its performance is simulated using OrCAD software. Based on the obtained results, the maximum voltage of the output pulse is 40 times the input voltage in a single-stage structure. An 80-W prototype of the proposed structure was built to validate the accuracy of the theoretical foundation and the simulation results.

Design of 4-stage Marx generator using gas discharge tube

Abstract: In this paper, a Marx generator voltage multiplier as an impulse generator made of multi-stage resistors and capacitors to generate a high voltage is proposed. In order to generate a high voltage pulse, a number of capacitors are connected in parallel to charge up during on time and then in series to generate higher voltage during off period. In this research, a 6kV Marx generator voltage multiplier is designed using gas discharge tube (GDT) as an electronic switch to breakdown voltage. The Marx generator circuit is designed to charge the storage capacitor for high impulse voltage and current generator applications. According to IEC 61000-4-5 class 4 standards, the storage capacitor must be charged up to 4 kV. The results show that the proposed Marx generator can produce voltages up to 6.8 kV. However, the storage capacitor could be charged up to 1 kV, instead of 4 kV in the standard. That is because the output impulse voltage has narrow time period.

Design of a High-Power UWB Antenna Incorporating a Solid Dielectric for Electronic Warfare Applications

Abstract: In this paper, a high-power ultrawideband antenna is presented for the purpose of remotely neutralizing improvised explosive devices. The developed antenna has a bandwidth between 230 MHz and 2 GHz, as well as a maximum realized gain of 18.7 dB. The antenna structure incorporates a solid dielectric (HDPE 1000) so that it can be powered, without risk of a possible breakdown voltage, by a Marx generator which delivers a bipolar pulse with a peak amplitude of +/−250 kV, a rise time of 170 ps, and a duration of 1 ns. The radiated electric field obtained in simulation is, respectively, 1 MV/m peak and 126 kV/m peak at a distance of 1 m and 10 m.

Additional lens for TEM horn antenna and transient high-power application: Design and Characterization in time domain

Abstract: This paper presents the design of a dielectric lens dedicated to transient High Power Microwaves (HPM) short pulses radiation. The proposed lens has been developed as an optional component that could be used to increase the directivity, and therefore the range, of a mobile HPM source. The associated emitter consists in a TEM horn, powered by a Marx generator and a dedicated pulse forming line (400 kV - 50 Ohms output voltage, total duration of 1.5 ns) [1]. The emission of very high amplitude nanosecond signals covers an ultra-wideband of frequencies, so the design of the lens was carried out in time domain. Here, the goal was to convert the pseudo spherical wave into a plane wave at the aperture of the aerial, for the considered impulse. Once manufactured, the near fields and the far fields have been measured with and without the lens. The maximum gain increases by at least 6 dB beyond 1.3 GHz and can reach 12 dB for higher frequencies. In time domain, the peak amplitude has been multiplied by a factor 2.65 allowing to reach a figure of merit of 2 MV/m.

Solid-State Marx Generator Circuit Based on Inductive Energy Storage

Abstract: Solid-state Marx generator circuits have been widely studied in recent years. Most of them are based on capacitive energy storage (CES), with the basic principle of charging in parallel and discharging in series. In this article, we propose a solid-state Marx circuit using inductive energy storage, where inductors play the role of principal energy storage element. When combined with an opening switch, the inductor can generate an output voltage of $L$ dI / dt, where $I$ is the inductor current. Multiple circuits can be stacked to obtain output voltage adding, as in Marx circuit using CES. In the demonstration experiments, the test on a four-stage inductive Marx circuit has been carried out. With the charging voltage of −200 V, the output peak voltage of ~9.2 kV was generated on an 800- $\Omega $ load with a rise time of ~46 ns.

Generation of HVDC from Voltage Multiplier Using Opto-Isolator and Marx Generator

Abstract: The main function of MARX generator is to produce a high potential pulse for testing the insulation of the electrical instruments such as transformers and electrical lines. However, power losses in conventional Marx generator due to capacitor and resistor are still a challenging task. A very few papers are reported in this direction. To fill this gap, method to implement the other static devices in place of conventional components is discussed. The presented topology comprises of a MOSFET, a capacitor, and two diodes. A 555 timer has been used to give pulses to the passive elements (capacitors) to be charged in parallel during ON interval. During OFF interval, charge storage devices are connected in series with the help of solid-state switches. Hence, MOSFET is used as a switching device; lossless charging of capacitors is done with the help of diodes. A comparison between different level generators is made and result is presented. The performance of the system is evaluated with the help of simulation results of PROTEUS software.

Utilizing a High-Speed Marx Supply Modulator in an Amplitude-Modulated Mixerless Transmitter for 64 QAM

Abstract: This article reports on the theory and application of a high-speed Marx generator (HSMG) circuit to realize supply modulation (SM). In order to achieve high-modulation bandwidth, the supply modulator complexity is kept low, enabling multilevel SM with four discrete voltage levels. A prototype is designed and fabricated on a four-layer FR4 board. The efficiency of the proposed modulator is measured with passive loads, achieving 89% at the 5-MHz switching frequency. Applied to a power amplifier (PA), the modulator demonstrates an error vector magnitude (EVM) of 2.64% at 10-MHz switching frequency with a four-ASK signal. Finally, the HSMG is utilized in an innovative mixerless transmitter architecture. Its capabilities are validated at the center frequency of 3.5 GHz for different modulation bandwidths from 2 up to 70 MHz and different constellation schemes—16 QAM, 32 QAM, and 64 QAM. EVM of 5.88% at 10-MHz bandwidth with 64 QAM is obtained without digital predistortion (DPD).

Characterization of Flash X-Ray Source From a Marx-Based Pulse Power System

Abstract: The source characterization of a Flash X-ray (FXR) device is essential in defining its utility for dynamic radiography. A Marx generator [550 kV, $50~\Omega $ , and 45 ns full-width half-maxima (FWHM)] based FXR source operating in the voltage range 200–550 kV has been characterized. The FXR electron beam diode has a cylindrical geometry with stainless steel (SS) knife-edge cathode and tapered tip Tungsten rod as anode. The FXR source is connected to the Marx generator-based pulsed power system using a flexible high-voltage cable feed through. The hard X-ray spectrum was measured using a differential absorption spectrometer (DAS). The FWHM of the spot size of FXR source was measured using a pinhole camera and was estimated to lie between 1.83 and 2.31 mm. The on-axis dose measured at 1 m matches well with the calculated dose $D \alpha V^{2.2}I\Delta t$ , where $V$ is the applied voltage and $I$ is the current, and $\Delta t$ the time duration.

Design, Analysis and Hardware Implementation of Modified Bipolar Solid-State Marx Generator

Abstract: Bipolar Marx generator generates high voltage, repetitive pulse with both positive and negative half, which is being used for application like food processing industries, medical fields, agricultural and environmental. This paper deals with design, simulation, implementation and testing of the bipolar Marx generator. Simple monopolar Marx generator is modified by connecting an H-bridge circuit to the last stage. Ten-stage bipolar Marx generator topology with specification, output voltage 10 kV, 10% voltage droop, pulse repetitive frequency (PRF)—1 kHz and pulse width of 5 µs is designed and simulated using MATLAB (R2009a). The most suitable inductor and resistor required for charging are selected using transfer function modeling. A two-stage prototype is implemented to validate the design. Pulses for triggering the Marx switches and the H-bridge switches are developed using LPC2148 arm controller. Hardware circuit is tested with an input of 100 V and PRF of 110 Hz. During erection, the full voltage appears across the switches in the H-bridge. Hence, this can be used only for few kilovolts.

Testing of a Bipolar Solid-State Marx Generator for Berlin BESSY II Injection Kicker System

Abstract: This article describes the preliminary results from the new bipolar solid-state Marx generator proposed for Berlin BESSY II injection system, which includes the following pulse specifications: (1) peak voltage of ±8 kV, (2) peak current of 160 A, (3) impedance of $50~\Omega $ , (4) frequency ≤10 Hz, (5) width of 350 ns, (6) risetime ≤80 ns, and (7) deviation from “Flat top” ≤ ± 1%. The generator is based on SiC metal-oxide-semiconductor field-effect transistors (MOSFETs) in order to allow fast risetime/falltime, where the charging of the main capacitors is from resistive paths. A generator with ten stages, using a dummy load that simulates a kicker magnet, is experimentally tested in order to study the overall performance, and results are presented and discussed.

Mathematical Modeling of Peaking Switch

Abstract: Marx generator followed by a coaxial peaking stage can act as a high-power impulse source. Peaking stage consists of a peaking capacitor followed by a pressurized spark gap. This has been used in many civil and military applications, which includes pulsed radar to detect buried mines or buried people, the electromagnetic compatibility of electronic equipment, food irradiation etc [1]–[5]. A spark gap switch design with repetition rate of 1–1000 pps and average power up to 10 kW is discussed by Winands et. Al. [6]. Switch is being designd to obtain spherical launching waves for an impulse radiating antenna is explained by Serhat Altunc et al [7]. An empirical formula for the breakdown field strength for a high- pressure SF6- gas filled spark gap switch is being developed by H. Rahaman et al [8]. Dr. Carl. E. Baum implemented a high voltage switch with very low-rise time output pulse using an array of smaller voltage switches [9]. An empirical scaling relationship between the mean electric field and the breakdown time has been developed in [10]–[12]. The limit of spark gap technology for ultrafast switching is explored by T. H. Martin et al [11]. Rise time in pico second (100 ps domain) pulse is generated through a high-pressure mm spark gaps [13]–[17]. Pulse- charged spark gap based on GaAs semiconductor photoconductive switches are explained by Ming XU et al [18].

Step-Down DC-DC Converter for Solid-State Marx Generator

Abstract: A compact step-down dc-dc converter has been developed for applications to solid-state Marx generator. The purpose is to allow Marx switches to be able to operate without direct power supply from the ground level circuits. The main voltage across the switch is used as the power source which is converted to a dc voltage that can be used to power the drivers of the solid-state switches. Experiments have been carried out to demonstrate the ability and the performance of the dc-dc converter, as well as its effectiveness in a four-stage Marx generator.

Pulsed Power Generators

Abstract: This chapter presents an overview of commonly used pulsed generators in bioelectrics. The concept of pulsed power is discussed in Sect. 15.1. One of the key components of ultrashort pulse generator is the switch that is capable of closing in time of nanoseconds or subnanoseconds. A variety of switches, including gas spark gap switches and MOSFETs, can be used (Sect. 15.2). Besides the switches, the circuits that are often used in producing ultrashort pulses are discussed in Sect. 15.3. Finally, when ultra-high voltage pulses are needed, an air-core transformer or a Marx generator can be used, which are discussed in Sect. 15.4.

A Compact High-Power Ultra-Wideband Bipolar Pulse Generator

Abstract: A compact high-power ultra-wideband bipolar pulse generator based on a modified Marx circuit is designed, which is mainly composed of a primary power supply, Marx generator, sharpening and cutoff subnanosecond spark gap switches, and coaxial transmission lines. The Marx generator with modified circuit structure has thirty-two stages and is composed of eight disk-like modules. Each module consists of four capacitors, two spark gap switches, four charging inductors, and a mechanical support. To simplify the design of the charging structure and reduce the number of switches, four groups of inductors are used to charge the capacitors of the Marx generator, two of which are used for positive voltage charging and the other two for negative voltage charging. When the capacitor of each stage is charged to 35 kV, the maximum output peak voltage can reach 1 MV when the Marx generator is open circuit. The high-voltage pulse generated by the Marx generator charges the transmission line and forms a bipolar pulse through sharpening and cutoff switches. All transmission lines used for bipolar pulse generation have an impedance of 10 Ω. When the 950 kV pulse voltage generated by the Marx generator is fed into the transmission line, the bipolar pulse peak voltage can reach 390 kV, the center frequency of the pulse is about 400 MHz, and the output peak power is about 15.2 GW.

A Prototype of a Pulsed Electric Fields Treatment for Solid Foods in Batches

Abstract: In this work a Pulsed Electric Field (PEF) prototype is developed. A 10 stage Marx generator for HV pulses was designed and implemented. A batch chamber suitable for small quantities was built and a 3000V, 5μs pulse was measured. The system was tested with dried grape marc and works as expected.

Optimal Tuning of Parameters for Impulse Voltage Generator Using Soft Computing Technique

Abstract: Power system equipment must tolerate not only the rated voltage which corresponds to the highest voltage of a particular system but also over voltages. The protection of electrical power system equipment depends on the performance of insulation systems under transient over voltage conditions like lightning and switching applications. As a result, it is obligatory to test high voltage equipment during the initial stage itself. The main objective of this paper includes the simulation of impulse wave generation using Marx generator circuits under varying load conditions and the application of Genetic Algorithm in optimizing impulse generator circuit parameters. This results in power and cost savings and makes impulse testing more feasible. The circuit set up for the production of unidirectional and bidirectional oscillatory impulse surge voltages is simulated in MATLAB. These impulse voltages are used for the testing of EHV lines and equipment.