Simple 2D Model for Helical Flux-compression Generators

Abstract

This paper presents a simple but complete 2D model for helical flux-compression generators that overcomes many of the limitations present in existing zero-dimensional models. The generator circuit is effectively decomposed into separate z and; current carrying circuits, with each of the; circuits (rings) corresponding to a different current. Use is also made of a technique by which these rings are sequentially switched out of circuit. The approach proposed opens the way to a full understanding of the behavior of cascade systems of generators inductively coupled by dynamic transformers using the so-called flux-trapping technique. In addition, the model can also yield an important insight into the phenomena that differentiates the performance of small generators when primed by a capacitor, a battery, or an externally produced magnetic field. Finally, the numerical code developed in the paper can readily be adapted to model high-energy and high-current generators in which the helical coil and the armature are of variable geometry. Valuable design information is provided on the magnetic and the electric field distributions within the generator and on the likely radial and axial movements of the stator turns.

Numerical Modelling of a Flyer Plate Electromagnetic Accelerator

“…By integrating the system of first-order differential equations (1)-(3), (14), and (15), using for example the MATHCAD 15 Runge-Kutta built-in subroutine, the solution can be easily found.…”

“…A number of original features have recently been introduced into the standard approach (also termed network mesh or meshmatrix method), mostly related to the fast dynamics of imploding/exploding metallic structures. The technique has been successfully applied by Loughborough along the years in a very wide range of pulsed power applications, including pulsed ultrahigh magnetic field coils [12], explosively driven fluxcompression generators [13], [14], single and multiturn electromagnetic launchers [15]- [17], electromagnetic launchers [15]- [17], electromagnetic compression [18], and the design of various types of high-voltage air core pulsed transformers [19].…”

“…where F column (i) is the total force acting on the i-th column similar to (14), and v column (i) and y column (i) stand for the i-th column vertical velocity and position, respectively, with initial conditions v column (i)| t=0 and y column (i)| t=0 = d/2. The column mass is m column = n y ρ flyer l∆yf ∆xf , where ρ flyer is the mass density of the flyer.…”

Filamentary modeling of pulsed high-current systems

“…The Loughborough filamentary technique for the 2D modeling of flux-compression generators is well-known, being published 15 years ago [7][8]. More recent very detailed results are shown in Fig.…”

Modeling and Simulation of Simple Flux-Trapping FCGs Utilizing PSpice Software

“…Numerical models of FT-FCGs available in open literature involve the use of 2-D analysis to write characteristic equations of the circuit. A thorough 2-D analysis is given by Novac et al in [2] and [3]. Analysis of this nature has also been used in Russian publications [4].…”