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This paper presents the design and construction of a sample of Marx pulsed generator based on boost converter (BC) pulse-forming networks (BCPFNs). BCPFN is used instead of the conventional Marx floors for constructing this pulsed generator. BCPFN is carried out by connecting inductors and capacitors in series and parallel modes, respectively, by using solid-state switches, and during this procedure the pulsed generator converts to BC temporarily and increases the voltage of capacitors uniformly to a considerable value. This technique causes an increase in the discharging voltage level to the load that is many times more than its dc voltage source by charging the capacitors to a greater level. In order to take advantage of the benefits of Marx generator and PFN, this paper suggests a new circuit with the minimum number of switches. It means, to compose BCPFN and Marx, we have tried to design the circuit with fewer switches and instead of it we have achieved our desired performance with changing the operating mode in the states of BC, PFN, BCPFN, and BCPFN Marx. The results are simulated with MATLAB software. At the end, the experimental results of the construction of the above-mentioned system at low-power levels are presented, and the topology’s accuracy is proved by comparing them to the results of simulation. [ABSTRACT FROM AUTHOR]

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]

The meat grinder is a basic circuit for inductive pulsed-power supply (IPPS). Based on meat grinder, the Institute of Advanced Technology proposed a circuit called the slow transfer of energy through capacitive hybrid (STRETCH) meat grinder, in which an Integrated Gate Commutated Thyristors (IGCT) is selected as the main switch. Tsinghua University proposed the STRETCH meat grinder with inverse current commutation with semiconductor devices (ICCOS) in which the main switch is replaced by a thyristor and the ICCOS subcircuit is introduced to turn off the main switch. To reduce the opening switch voltage and increase the current turning-off capacity for IPPS, this paper presents a novel circuit topology named the meat grinder with self-charged capacitor and thyristors (SECTs). The key idea of the SECT topology is to turn off the primary current by the energy transfer capacitor, which is precharged. The meat grinder with SECT has larger capacity than the STRETCH meat grinder because it replaces the IGCT with a thyristor and is simpler than the STRETCH meat grinder with ICCOS because it only needs one capacitor. The suggested circuit is more suitable for IPPS module with high energy density. Simulation and experiment have been carried out to validate the circuit. [ABSTRACT FROM PUBLISHER]

This paper describes the design and implementation of a three-phase resonant converter with low ripple and high control accuracy. Based on a three-phase LCC-type resonant converter—which has advantages of low ripple, high-efficiency, and high-power density compared with a single-phase converter—a high-voltage power supply with low ripple (<0.1%) was designed. In addition to the general merits of an LCC-type resonant converter operating at continuous conduction mode—including soft switching, low conduction loss, and current source characteristics—the proposed scheme uses only one phase under a light-load condition by having different leg designs of the gate drive circuit and snubber parameters. This allows the design to overcome the operational constraints of the general LCC-type resonant converter. The distinctive design of the three-phase converter structure provides high efficiency and low ripple not only during rated operation, but also under light-load conditions. In order to analyze the high performance of the proposed scheme from no load to rated load, a PSPICE simulation was carried out. Comparison results with a conventional LCC-type resonant converter based on a single-phase structure are analyzed from the viewpoints of output ripple, losses, and operable load range. Using the proposed converter, a 20-kV, 20-kW high-voltage dc power supply design and implementation was presented with a superior gate drive circuit. Finally, the superiority of the proposed converter was verified through a simulation and experimental results. It was experimentally confirmed that the developed power supply achieves high performance in terms of efficiency (98%), operable load range (0.5–20 kV), and low ripple (0.05%), with a high power density. [ABSTRACT FROM PUBLISHER]

A modular linear transformer driver (LTD) is a novel fast-discharge high-pulsed power source for primarily stored energy. In LTDs, a large number of stages (or cavities) can be connected in series or in parallel conveniently to directly generate high power pulses of 50–200 ns with the required voltage or current. This paper introduces an LTD stage developed by us recently. This LTD stage consists of 14 bricks in parallel. Each brick contains two 40-nF capacitors and a compact multigap gas spark switch in series. The switch is a modification of our original version, and the diameter and the height of which have been reduced to 98 and 127 mm, respectively. The circuit model of this stage is established in PSPICE, and its output parameters are obtained through simulation. Driving a rough-matched resistive load of 0.27 \Omega, its output current peak is 300 kA with an overall rise time of about 110 ns at a charged voltage of the capacitors of about \pm90 kV, agreeing well with its simulation result. [ABSTRACT FROM PUBLISHER]

When small currents are interrupted by a vacuum switch, it is well known that the chopping current and the associated overvoltage are observed. Many investigations on the current-chopping phenomena in alternating-current (ac) circuits have been carried out, but there are no data available on inverter circuits in spite of their recent wide application to synchronous motor systems. In this paper, chopping-current levels and the overvoltages in an inverter circuit under a simple three-level pulsewidth-modulated control are investigated. As a result, the mean chopping-current level is three to four times higher than that in an ac circuit. In particular, high chopping currents occur only when the timing of the current interruption by the vacuum switch synchronizes with that of the inverter's switching, which we call “double chopping.” High chopping current due to double chopping might be harmful since the high overvoltage proportional to the chopping-current level could damage the insulation of electric equipment. However, we experimentally confirmed that a typical surge suppressor could reduce overvoltage. [ABSTRACT FROM AUTHOR]