Vector inversion generator
Encyclopedia
A vector inversion generator (VIG) is an electric pulse compression and voltage multiplication device, allowing shaping a slower, lower voltage pulse to a narrower, higher-voltage one. VIGs are used in military technology, e.g. some directed-energy weapon
s, as a secondary stage of another pulsed power source, commonly an explosive-driven ferroelectric generator
.
also acting as a single-ended transmission line
, connected to a spark gap
switch. The capacitor is charged from a power source, e.g. the EDFEG, then the spark gap fires after its breakdown voltage
is reached. The electromagnetic wave created by the electric spark
discharge travels along the transmission line, converting electrostatic field to electromagnetic field
, then after reflecting from the open end converts back to electrostatic field. A pulse of output amplitude 2nU (where n is the number of turns of the capacitor and U is the initial voltage it was charged to) and a rise time equal to twice the electrical length of the transmission line. The device acts as a distributed pulse forming network
.
Ferrite
s can be attached to the VIG construction to modify its characteristics.
s in range of nanoseconds. Some VIGs can be configured as part of a tuned circuit, acting as oscillators with practical upper limit of about 700 MHz, generating energy that can be radiated from a suitable antenna
, allowing construction of very simple explosion-generated electromagnetic pulse
generators.
The use of VIGs includes directed-energy weapon
s, x-ray
pulse power supplies, plasma
generators, etc.
VIGs can be constructed by high-voltage hobbyists.
Directed-energy weapon
A directed-energy weapon emits energy in an aimed direction without the means of a projectile. It transfers energy to a target for a desired effect. Intended effects may be non-lethal or lethal...
s, as a secondary stage of another pulsed power source, commonly an explosive-driven ferroelectric generator
Explosive-driven ferroelectric generator
An explosive-driven ferroelectric generator is a compact pulsed power generator, a device used for generation of short high-voltage high-current pulse...
.
Construction
A spiral VIG consists of four alternating conductor-insulator-conductor-insulator sheets, wound into a cylinder, forming a capacitorCapacitor
A capacitor is a passive two-terminal electrical component used to store energy in an electric field. The forms of practical capacitors vary widely, but all contain at least two electrical conductors separated by a dielectric ; for example, one common construction consists of metal foils separated...
also acting as a single-ended transmission line
Transmission line
In communications and electronic engineering, a transmission line is a specialized cable designed to carry alternating current of radio frequency, that is, currents with a frequency high enough that its wave nature must be taken into account...
, connected to a spark gap
Spark gap
A spark gap consists of an arrangement of two conducting electrodes separated by a gap usually filled with a gas such as air, designed to allow an electric spark to pass between the conductors. When the voltage difference between the conductors exceeds the gap's breakdown voltage, a spark forms,...
switch. The capacitor is charged from a power source, e.g. the EDFEG, then the spark gap fires after its breakdown voltage
Breakdown voltage
The breakdown voltage of an insulator is the minimum voltage that causes a portion of an insulator to become electrically conductive.The breakdown voltage of a diode is the minimum reverse voltage to make the diode conduct in reverse...
is reached. The electromagnetic wave created by the electric spark
Electric spark
An electric spark is a type of electrostatic discharge that occurs when an electric field creates an ionized electrically conductive channel in air producing a brief emission of light and sound. A spark is formed when the electric field strength exceeds the dielectric field strength of air...
discharge travels along the transmission line, converting electrostatic field to electromagnetic field
Electromagnetic field
An electromagnetic field is a physical field produced by moving electrically charged objects. It affects the behavior of charged objects in the vicinity of the field. The electromagnetic field extends indefinitely throughout space and describes the electromagnetic interaction...
, then after reflecting from the open end converts back to electrostatic field. A pulse of output amplitude 2nU (where n is the number of turns of the capacitor and U is the initial voltage it was charged to) and a rise time equal to twice the electrical length of the transmission line. The device acts as a distributed pulse forming network
Pulse forming network
A Pulse Forming Network accumulates electrical energy over a comparatively long time, then releases the stored energy in the form of a relatively square pulse of comparatively short duration for various pulsed power applications...
.
Ferrite
Ferrite (magnet)
Ferrites are chemical compounds consisting of ceramic materials with iron oxide as their principal component. Many of them are magnetic materials and they are used to make permanent magnets, ferrite cores for transformers, and in various other applications.Many ferrites are spinels with the...
s can be attached to the VIG construction to modify its characteristics.
Applications
VIGs are advantageous due to their simplicity and the very short pulse rise timeRise time
In electronics, when describing a voltage or current step function, rise time refers to the time required for a signal to change from a specified low value to a specified high value...
s in range of nanoseconds. Some VIGs can be configured as part of a tuned circuit, acting as oscillators with practical upper limit of about 700 MHz, generating energy that can be radiated from a suitable antenna
Antenna (radio)
An antenna is an electrical device which converts electric currents into radio waves, and vice versa. It is usually used with a radio transmitter or radio receiver...
, allowing construction of very simple explosion-generated electromagnetic pulse
Electromagnetic pulse
An electromagnetic pulse is a burst of electromagnetic radiation. The abrupt pulse of electromagnetic radiation usually results from certain types of high energy explosions, especially a nuclear explosion, or from a suddenly fluctuating magnetic field...
generators.
The use of VIGs includes directed-energy weapon
Directed-energy weapon
A directed-energy weapon emits energy in an aimed direction without the means of a projectile. It transfers energy to a target for a desired effect. Intended effects may be non-lethal or lethal...
s, x-ray
X-ray
X-radiation is a form of electromagnetic radiation. X-rays have a wavelength in the range of 0.01 to 10 nanometers, corresponding to frequencies in the range 30 petahertz to 30 exahertz and energies in the range 120 eV to 120 keV. They are shorter in wavelength than UV rays and longer than gamma...
pulse power supplies, plasma
Plasma (physics)
In physics and chemistry, plasma is a state of matter similar to gas in which a certain portion of the particles are ionized. Heating a gas may ionize its molecules or atoms , thus turning it into a plasma, which contains charged particles: positive ions and negative electrons or ions...
generators, etc.
VIGs can be constructed by high-voltage hobbyists.