Marx generator

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

EMIR-M installation in the mode of operation with plasma opening switch

Abstract: The EMIR-M generator is modified to perform a series of experiments to explore the Plasma Opening Switch (POS). Results of the first experiment with POS are described. EMIR-M operates in two different modes: first one, with Marx generator voltage of 0.95 MV and current of 300 kA; second one, 1.42 MV and 460 kA, correspondently. Vacuum diode and inductance (short-circuit diode) was used as a load. PIN-diodes and TLD detectors are used for radiation parameters measurements. The results have been obtained: voltage gain of 2.6; maximum conduction time of 2.3 /spl mu/s; Current rise rate up to 3.10/sup 1/3 A/s with front duration of 10/spl divide/13 ns has been measured.

Computer simulations of a pulsed power electron beam generator

Abstract: A computer simulation of a pulsed power electron beam generator with about IOOGW instant electric power output is studied. The device is composed of 1.5 MV, 21 kJ Marx generator, a 9/spl Omega/ water filled Blumlein line, a coaxial transformer and a 2.6MV field emission diode. The maximum diode current is about 35kJ and th pulse width of voltage is 90n sec. A numerical model which will yield electrical performances in better agreement with the experimental results and simulate the generator's components by using lumped equivalent circuit has been developed. The hard-to-calculate parameters are obtained by simple experiments as compared with simulation results. The comparison of code and experimental results shows that the differences are within 5%. The efficiency of the device is about 35%.

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.

SINAPS 2000: An 1MJ, 2 MA inductive store/opening switches generator

Abstract: In order to build an 1 MJ, 2 MA, 1 /spl mu/s pulsed power generator based on the use of inductive storage and plasma opening switches (POS), an R&D program was carried out at CEA-CESTA. This paper presents the results obtained with three mock-ups. Some critical points of this type of generators were studied with few components (16 capacitors and 8 switches). The first configuration (360 kV, 900 kA on a short circuit, 0.8 /spl mu/s) consisted of 4 Marx generators with two-stage capacitor banks to test the switches and evaluate the self-inductance of one stage. The second configuration (180 kV, 1.4 MA on a short circuit, 1.4 /spl mu/s) consisted of a capacitor bank using 8 Marx generators of one stage to study parallel Marx generator triggering. The authors also tested a POS stage on this experimental set-up. In the third configuration (720 kV, 400 kA), the capacitor bank was made of 2 Marx generators of 4 stages in order to study the voltage strength of the circuit components. In conclusion, the authors present the design and the progress in the mounting of the whole generator.

Electrostatic modelling of critical electrical components of the Mevex X-ray machine

Abstract: Summary form only given. The Opera-3D electrostatic modelling software, Tosca, has been used to model Mevex, a type of X-ray machine used at AWE for flash radiography since the early 1980s. The operating principle of the machine is to switch charge, stored in a Mark bank, into a Blumlein pulse-forming line. This causes the inner line of the Blumlein to rise in voltage to about 700 kV, driving a self-magnetic pinch (SMP) diode to produce a 60-nanosecond X-ray pulse. Currently, the machine design is being refreshed to enhance operability. This study is concerned with possible electrostatic breakdown of critical components, in particular the spiral-inductor, part of the balance circuit, and the high-voltage feed-through from the Marx generator to the Blumlein intermediate conductor. The geometry of the spiral-inductor, though difficult to specify, is generated in the Opera-3D modeller by creating a spiral wire-edge and sweeping a disc along it, from one end to the other, maintaining normality between it and the local direction of the spiral wire-edge. A functional voltage boundary condition is applied to the spiral surface in terms of the length around the spiral wire-edge, which can be determined analytically. The process is not straightforward since a general point on the surface of the spiral does not lie on the wire-edge at its core. In order to implement the boundary condition, an expression for the distance from the general surface point to the spiral wire-edge at its core must be established and minimised. This can be achieved in terms of the angular variable used to specify the spiral wire-edge. Since the resulting equation cannot be solved analytically, Newton-Raphson iteration is used to determine the solution numerically. In practice, this process is performed using a specially written command-interface (COMI) file which is executed automatically when the Opera-3D software is run. Electrostatic field strengths have been determined at the surfaces of the conductors of interest, as described above, and shown to be less than required to initiate breakdown. The work described in the poster has not been presented elsewhere.