Marx generator

About: Marx generator is a research topic. Over the lifetime, 1276 publications have been published within this topic receiving 8970 citations.

Reproducibility Improvement on High Voltage Self-Break Water Switches

Abstract: CESAR, a high current electron beam facility (800 kV, 400 kA) and AMBIORIX, a 2 MA Z-pinch driver are two of the main pulsed power facilities at CEA-CESTA in France. They use the classical technology of low-impedance generators, a Marx generator associated with a water line. One of the limitations of this kind of device is the switching process between the water lines. In order to improve the reproducibility, their first water switches were recently changed. On the basis of the work done by Puetz et al. for RITS-3 [1], the geometry of the main switch of each device, which links the intermediate storage (IS) and the pulse forming line (PFL), has been optimized. In this paper, we present the results of this modification.

Design strategies for a SiC Marx generator for a kicker magnet

Abstract: This paper discusses various design strategies and preliminary test results for a Marx generator with specifications of 40 kV, 3.2 kA, 3 μs pulse width, 30 ns rise and fall-times, and 1 Hz repetition rate, for possible replacement of a thyratron and PFL in an existing kicker system. The proposed topology will use 50 stages, each 800 V stage comprising 24 SiC MOSFETs in parallel, each MOSFET conducting about 140 A pulses. First tests using parallel SiC MOSFETs are described and results discussed in light of the proposed topology. Also the overall structure is discussed, as the parasitic inductances are a key issue for this application.

A Compact MW-Class Short Pulse Generator

Abstract: A megawatt-range short pulse generator based on the diode step recovery phenomenon and the Marx generator idea is presented. This generator utilizes both opening and closing switches in one circuit. The proposed circuit is compact, light, and low cost and is driven by a low-power source. By using a three-stage Marx generator, the output peak power of 0.6 MW was obtained. The dimensions of the generator are 8 cm $\times8$ cm. Experimental measurements of the output pulse characteristics showed a rise time of 100 ns for a 16- $\Omega $ load. The input peak power was 4 W which showed more than 105 times increase in the pulse peak power.

A subnanosecond high voltage pulser for the investigation of dielectric breakdown

Abstract: A high voltage, sub-nanosecond pulser is designed and built for the purposes of investigating dielectric breakdown. The requirement for the pulser is a voltage pulse of several hundred kilovolts, pulsewidth less than a few nanoseconds, and a risetime <400 psec. This is achieved by using pulse sharpening techniques on the output of a 500 kV Marx bank. Originally designed to stimulate a lightning strike, the voltage waveform from the Marx generator has a slow decay time of tens of /spl mu/sec. In order to obtain a more desirable pulse, the Marx bank is modified. By removing a lumped-element resistor a higher peak output voltage with a faster risetime can be obtained. Circuit simulations have shown the capability of achieving an 800 kV output in less than 40 nsec to a charging (pulse forming) line. The 50 /spl Omega/ impedance, oil-filled, pulse forming line consists of a peaking gap and pulse slicing gap. The peaking gap decreases the risetime of the applied pulse down to about 300 psec. The pulse slicing gap is included to short the voltage applied to the delay line and test chamber.

A microsecond marx bank for driving high current electron beams

Abstract: A fast Marx (220 kJ, 450 nH, 675 kV) has been developed as a driver for an electron beam generator. This generator uses an inductive store with an opening switch to compress and amplify the power pulse. The 220 kJ Marx consists of four parallel 55 kJ Marxes to minimize the inductance. The 220 kJ Marx has been used to develop vacuum opening switches. These opening switches have demonstrated up to 22% efficiency and pulse compression of 5 to 1. Two switch concepts have been successfully tested as electron beam diodes on this Marx bank. The energy delivered to diode, the output voltage and power produced by this new high power generator will be presented. This generator serves as the proof-of-principle demonstration of inductive store/opening switch technology as an alternative to conventional capacitive store waterline technology.