Marx generator

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

Gate Drive Power Supply with Low Insulation Voltage Transformer for in-vehicle Marx Circuit

Abstract: This paper proposes a gate drive circuit with a low-insulation voltage transformer for an in-vehicle Marx circuit. The Marx circuit will be used for NOx gas decomposition for diesel vehicles as a part of an ozonizer. In order to make the Marx circuit on board, it is necessary to reduce the size and cost of the circuit, including the gate drive circuits. One of the bottlenecks for lowering the cost and size of the gate drive circuit is the insulation transformers on the gate drive circuits because the potential of each switch of the Marx circuit dynamically changes from zero to the output voltage of the Marx circuit. This paper proposes and demonstrates the gate drive circuit, which receives the drive power for the MOSFET on the n-th stage from $(\boldsymbol{n}-\mathbf{1})$ -th stage through a low-voltage transformer. Due to the configuration, the required insulation voltage of the transformer is equal to the input voltage. In this paper, the design procedure of the transformer with an approximated current is described. The proposed gate drive circuit is developed and implemented to the 4-kV Marx circuit.

All-solid-state Marx generator with saturable pulse transformer substituting for gas switch

Abstract: The invention discloses an all-solid-state Marx generator with a saturable pulse transformer substituting for a gas switch. The all-solid-state Marx generator is used for solving the problems that existing Marx generators are high in charging voltage, non-synchronous in capacitor charging, short in gas switch life or high in magnetic switch saturable inductance, series are hard to increase and the like. The all-solid-state Marx generator is composed of the saturable pulse transformer SPT, Q-grade Marx capacitor and grounding inductor units and a load, the SPT is in an axial symmetric structure, Q-group secondary windings of the SPT serve as a magnetic switch, Q-grade Marx capacitor and grounding inductor units are evenly distributed on the outer circumference of the SPT and are connected with Q-group secondary windings. Each grade of the Q-grade Marx capacitor and grounding inductor units is composed of a Marx capacitor and a grounding inductor. The all-solid-state Marx generator has the advantages of being low in input charging voltage, short in series connection, synchronization and built-up time of the switch, high and repetitive in operation frequency, solid and long in service life, a magnetic core can be reset automatically, and all grades of capacitors are charged uniformly.

Anode material outgassing at 250 A/cm 2 current density under UHV conditions

Abstract: Summary form only given. This presentation describes a study on gas evolution of plasma expansion in a reflex-triode virtual cathode oscillator (vircator) at ultra-high vacuum (UHV). Research has shown that explosive electron emission (EEE) processes at the cathode and ion / electron bombardment at the anode cause material erosion that produces regions of localized plasma. This plasma expansion has shown to lower gap impedance, cut off microwave performance and spoil low vacuum levels over time1. The goal of the study is to identify the gas species and their sources to better understand and limit the negative effects of plasma expansion in sealed tubes. The vacuum tube under investigation is a triode-geometry vircator with 20 cm2 cathode surface, driven by a 80 J Marx Generator with an approximate peak voltage and current, and pulse width of 200 kV and 5 kA, and 200 ns, respectively.

A microsecond-pulsewidth, intense, light-ion beam accelerator

Abstract: A relatively long-pulsewidth (0.1 - 1.0 μs) intense ion beam accelerator has been built for materials processing applications. An applied-Br, magnetically-insulated extraction ion diode with dielectric flashover ion source is installed directly onto the output of a 1.2-MV, 300-kJ Marx generator. Initial operation of the accelerator at 0.4 MV indicates satisfactory performance without the need for additional pulse-shaping.

Reducing PFN marx generator size using nested solid insulation

Abstract: Current state-of-the-art, high voltage, pulsed power systems above 0.5 GW output power, generally use Marx or Pulse Forming Network (PFN) Marx generator designs. The high voltage insulation of these devices has been traditionally based on either high dielectric strength oil or sulfur hexafluoride (SF6). The dielectric strength of the insulating medium determines the minimum size of the tank enclosure of the system since it determines the maximum voltage standoff between the fully erected Marx output voltage and the tank wall. We have applied our “Nested High Voltage” (NHV) insulation technology to the problem of PFN pulse generator design. This technique uses solid insulation with field grading foils that minimized the distance from the fully erected voltage and the tank wall. This report describes work performed in adapting this technology to building a PFN pulse generator. We believe that this technology will allow size reductions relative to other insulation technologies. The technology also allows integration of the PFN charge power supply into the PFN. Data will be presented on the performance of a 130kV version of this type of device capable of up to 5kA output. We demonstrated that making a “flat” pulse is feasible in this geometry, and we determined that there is an optimal grading technique for this type of design. Both high gradient insulation and pulse generation have been demonstrated and will be described. The systems will be useful in the 50kV – 2 MV range with impedances in the 20 – 200 ohm range.