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In the Russian State Research Center, Troitsk Institute of Innovation and Fusion Research, the first two power-amplifier cascades of the MOL stand are put into operation. This paper presents the description of the stand stages and the results of experiments on the current amplification. In the experiment, under the MOL's charging current of 20 kA, the second-stage output current of 1.6 MA was obtained. [ABSTRACT FROM AUTHOR]

The Caltech spheromak experiment uses a size A ignitron in switching a 59-μF capacitor bank (charged up to 8 kV) across an inductive plasma load. Typical power levels in the discharge circuit are ∼200 MW for a duration of ∼10 μs. This paper describes the setup of the circuit and the measurements of various impedances in the circuit. The combined impedance of the size A ignitron and the cables was found to be significantly larger than the plasma impedance. This causes the circuit to behave like a current source with low energy transfer efficiency. This behavior is expected to be common with other pulsed plasma experiments of similar size that employ an ignitron switch. [ABSTRACT FROM AUTHOR]

The next linear collider (NLC) accelerator proposal at Stanford Linear Accelerator Center (SLAC, Menlo Park, CA), requires a highly efficient and reliable, low cost, pulsed-power modulator to drive the klystrons. A solid-state induction modulator has been developed at SLAC to power the klystrons; this modulator uses commercial high voltage and high current insulated gate bipolar transistor (IGBT) modules. Testing of these IGBT modules under pulsed conditions was very successful; however, the IGBTs failed when tests were performed into a low inductance short circuit. The internal electrical connections of a commercial IGBT module have been analyzed to extract self- and mutual partial inductances for the main current paths as well as for the gate structure. The IGBT module, together with the partial inductances, has been modeled using PSpice. Predictions for electrical paths that carry the highest current correlate with the sites of failed die under short circuit tests. A similar analysis has been carried out for a SLAC proposal for an IGBT module layout. This paper discusses the mathematical model of the IGBT module geometry and presents simulation results. [ABSTRACT FROM AUTHOR]

This paper presents a fast, memory efficient, and accurate method to calculate the current distributions in solid wires in wire z-pinch arrays. Building upon previous work, we reformulate inductance equations to significantly reduce the number of variables from NwxNb to Nw+ Nb -1, where Nw is the number of wires and Nb is the number of return conductor elements, or "backposts." Test cases of Nw and Nb in the hundreds show reduction of computing time by as much as five orders of magnitude. Extension of this inductive model to include resistive effects is indicated. [ABSTRACT FROM AUTHOR]

In this paper, a novel six-channels annular plasma-jet chamber is designed and embedded in the trigger electrode of the three-electrode gas switch to generate multichannel plasma jets without air flow, which is used to trigger the gas switch to form multichannel discharge. Results of this paper show that the plasma-jet triggering can be conductive to steady formation of multichannel discharge. [ABSTRACT FROM PUBLISHER]

The pseudoliquid (PSL) armature with air spring is a novel railgun armature which has been fired successfully many times in a simple railgun by a united research group led by Beijing Institute of Special Electromechanical Technology (BISET), and the results of these experiments show that this armature can prevent transition in some conditions. Multiple turns in a railgun can significantly increase the inductance gradient of the launcher and decrease the needed current. Therefore, BISET initiated a program to launch projectiles with PSL armatures by a two-turn railgun. This paper presents an overview of this program, including the pulsed-power supply, a two-turn rail launcher, projectiles, and some experimental results. Further experimental studies are being continued. [ABSTRACT FROM AUTHOR]