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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]

A 200 kJ pulsed power system (PPS) has been built up to drive pulsed plasma devices. This PPS consists of two 100 kJ capacitor bank modules, each comprising of five capacitors of each 178~\mu \textF , a discharge switch, and a pulse-shaping unit. When both the banks are charged simultaneously to −15 kV using full charging technique, it delivers a peak current 100 kA at the load (damping resistor and pulse-shaping inductor). Later on, a plasma system will be attached at the load which will also have an inductive and resistive effect. A fiber-optic triggering unit controls both the modules and there exists a flexibility of sometimes operating a single module only, besides there are provisions for further up gradation of the PPS to a targeted 600 kJ. Prior to this development, PSpice simulation was carried out to estimate the parameters of the circuit components to achieve the required wave pulse with precision. Using these parameters, a design of the PPS was made keeping into account about the critical issues involved and the ratings of the components, some of which were fabricated in house. This paper basically includes the criticality surrounding the operation of a high-energy long-pulse PPS under negative operating voltage. [ABSTRACT FROM AUTHOR]

The parallel operation of array microhollow cathode (MHC) discharges is studied to generate high density of electrons owing to its multichannel MHC discharges. To ignite all the holes synchronously in one pulse, a pretrigger device is introduced, which is composed of three layers (two electrode layers and a dielectric layer). With the pretrigger process, some initial electrons can be injected into the holes, which makes array MHCs easier to ignite and improves the behavior of parallel operation. In this paper, the array MHC discharges with pretrigger in one pulse mode are presented and the influence on the parallel operation of the pretrigger process is studied. At last, the simulation result is given to have a better understanding of the pretrigger mechanism. [ABSTRACT FROM AUTHOR]

The superconducting inductive pulsed-power supply (SPPS) circuit consists of a high-temperature superconducting pulsed-power transformer (HTSPPT) and an auxiliary capacitor. The electrical losses and the power of the primary source can be cut down with the superconducting inductive energy storage. Although its energy density is slightly less than a purely superconducting inductive system, it can reduce the maximum voltage of the opening switch by the capacitor and achieve a high degree of current amplification factor. However, during the discharge process, the magnetic leakage flux energy stored in the primary of the HTSPPT requires the capacitor to have a certain capacity. The higher the ratio of the capacitive stored energy over the total inductive stored energy, the more the dominant position of inductive energy storage reduces. The current amplification factor ( \gamma ), the maximum voltage of the opening switch ( V_{S\max } ), and the ratio of capacitive stored energy ( \eta ) are the three main properties of the SPPS circuit, which depends on several intertwined critical parameters, such as the inductance ratio n = L2 /( L2+LL ) and the capacitance ( $C_{{\mathbf {1}}}$ ). This paper studies the influence of the critical parameters on the main circuit performance with a 1-kJ SPPS system. The detailed selection method of the critical parameters for the specific system is also discussed with a coupling coefficient of 0.95. Such a system is easy to be utilized for the basic experimental study of a small railgun. [ABSTRACT FROM PUBLISHER]

Our understanding of warm dense matter (WDM) properties will help to unravel the formation and evolution of giant planet, including gaseous giants or mega-Earths. However, the production of WDM in the laboratory is limited to samples on the order of tens of micrometers. This raises many challenges to measure the properties of WDM using standard diagnostics. In this paper, we propose a new method to produce WDM samples using pulsed-power machines. We numerically demonstrate that the early expansion phase of the sample, usually encountered in pulsed-power systems, can be virtually eliminated using a current switching scheme. To avoid mixing the plasma and WDM states, the present strategy uses a gas-puff $Z$ -pinch as a closing plasma switch. During the first part of the discharge, most of the current flows inside a gas-puff $Z$ -pinch, preventing the heating of the sample. During this phase, the gas $Z$ -pinch radially converges toward the sample. When the $Z$ -pinch finally reaches the sample, all the $Z$ -pinch current switches to the sample and rapidly heats it. The strong azimuthal field generated by the $Z$ -pinch prevents the expansion of the sample. If the initial gas pressure is carefully chosen, the sample reaches a quasi-homogeneous WDM state. The efficiency of the method allows one to produce millimeter-size WDM samples with a 500-kA pulser. [ABSTRACT FROM PUBLISHER]

Two-electrode graphite spark gap switch (TGSGS) is used as the main discharge switch and triggered by a reliable trigger generator in pulsed power conditioning system (PPCS). There would be 108 energy modules in PPCS working at the same time. The reliable operating and jitters of the trigger generators will have impact on the PPCSs performance. In this paper, the working modes of the TGSGS are discussed and the performance of trigger generators in PPCS is tested and presented. A protection strategy of the trigger generator in PPCS is introduced, and effect of the blocking capacitor on the trigger pulse transmission is analyzed and tested. The protection strategy of the trigger generator based on blocking capacitor and fuse can effectively prevent the energy anti-irrigation failure when the pulse transformer core saturated. The blocking capacitor has some effect on the trigger pulse transmission, and has the larger capacitance, getting the higher peak amplitude on the cathode of the TGSGS. It is tried to discuss the working characteristics of the thyristors, and proposes a selection reference of the thyristors in this and other similar applications. The combination of analysis and measurement would be useful for the selection of thyristors and other components. [ABSTRACT FROM PUBLISHER]

Field distortion gas switches are extensively used in pulsed power systems. Switch performance typically degrades because of electrode erosion, which directly influences the output parameters, stability, and reliability of pulsed power systems. With the same value of $pd$ , different pressure and gap lengths in gas switches can affect electrode erosion property and thus, the subsequent performance degradation, but few results have been published. In this paper, repetitive discharges have been undertaken in a three-electrode field distortion gas switch with fixed pd$ to study the influence of pressure and gap length on electrode erosion and switch performance. The morphology of electrode surface and time histories of both trigger jitter and the probability of prefire have been investigated during the whole life cycle of the gas switch. The results show that when pd$ is fixed, high pressure and a short gap make for low trigger jitter at the start of the switch life cycle but lead to more severe electrode erosion, expediting the degradation of performance in field-distortion gas switches. Meanwhile, the probability of prefire increases rapidly with the increase of pressure. [ABSTRACT FROM PUBLISHER]