DE2138730A1 - Pulse shaper - Google Patents

Description

Amaelderln: Stuttgart ₈ des, August 2, 1971

Hughes Aircraft Company P2147

Centinela Avenue and OJeale Street

Culver City, Calif., V.StJU

The invention looks at it

a storage condenser

whose selenary winding in B®s? i © av / isehea of the Hj kondensator and the © load gesonaXiäet is ₅ w © g; eg © a deasi primary winding at © ine Impujlsquall © aagesekl © se @ a, and one of the durcli '"© in®a.aa dia P ^ imäswieklimg

applied impulse triggered, load flowing discharge current

Spaicherkondaator and activity.

209808/1901

As mentioned above, the have trigger transformers the purpose of such pulse shapers is to cause the pulse shaper α to discharge into the load. At acquaintances Both series and parallel triggering were applied to pulse shapers The parallel trigger arrangement is the secondary winding of the trigger transformer with a trigger electrode connected to the load, which is a flash lamp, one in the primary circuit

a step-up transformer for a magnetron switched thyratron or the like.If a pulse is fed to the primary winding of the trigger transformer, the higher voltage on the secondary winding initiates the initial ionization of the flash lamp and the stored charge of the pulse shaper with the ionization upright ₉ as long as the discharge takes place.

If the only purpose of the pulse shaper is to save energy, then an ordinary one will do Capacitor off. In many applications, such as the Laser «, however, the pulse generator not only has to store energy, it also has to shape the output signal in such a way that it that during a certain period of time in which the voltage at the pulse shaper can drop to zero, a steady one Output current is supplied «For this strobe control it is necessary to provide the pulse shaper with a series inductance to add · Although with such a parallel arrangement a good trigger "and good pulse shaping is achieved" increases the electromagnetic Interfering radiation dee trigger transformers around the interfering radiation the inductance of the pulse shaper

209808/1901

BAD ORfGfNAL

In the case of a series trigger arrangement, the secondary « winding dos Trfegertransformatore between the pulse former "and dio Last gaschwitches © £" in series - The initial ionization does not result in a 2riggerel®kte®e! © turns · Instead, there is di © in the secondary winding induced voltage to the potential of the storage agi added to initiate the ionization · As in the case © the parallel arrangement discharges- then see the and the electromagnetic is added the inductance of the pulse shaper from the interference radiation originating from the transformer *,

The invention is based on the task Simplify the previously known pulse shaper see below at the same time to be trained in such a way that oils radiate from magnetic interference fields is reduced.

This object is according to the invention characterized fe _Geloes-0 * that is used as a series inductance immediately the secondary "winding of the Triggertransf © raators and comprises for this purpose at least a portion of Transforms" torkernes of a material .niedriger saturation and di "inductance of the Secondary winding eo selected in ^ that when this grain size is saturated, the current takes the desired course »

In the pulse shaper according to the invention, the transformer's coil can be used as a II @ Xaduktionsspul® pulse shaper ₉ w @ il d © 2? The trigger transformer switched in legs is designed in such a way that it is used for the trigger as © In © g2? oß @

209808/1901 ORIGINAL BATHROOM

and during the discharge following the trigger pulse of the stored energy has a small inductance. This can be achieved * by increasing the inductance of the Trans formatoro ebonoo makes big like the only ßtromformung Desired inductance of a series output simile, if the current flow in the secondary winding exceeds the current required to initiate the discharge by to lower core gaps with a suitable material Saturation replenishes · To reduce the electromagnetic Radiation interference can continue to fill the secondary winding around the gap in the trigger transformer Low saturation material wrapped tightly around no and completely surrounding this material · Continue a high saturation material can be used to provide a low impedance path for return flow from a End of the secondary winding to create the other.

Further details and embodiments of the invention can be found in the following description, in which the Invention is described and explained in more detail with reference to the embodiment shown in the drawing. The features that can be inferred from the description and the drawing can form the invention in other embodiments Can be used individually or in groups in any combination · Show it

Fig. 1 is a schematic representation of a preferred embodiment of the present invention and

2 shows a diagram with characteristics of the transformer the embodiment shown in Fig. 1

2Q9S08 / 190

BAD OFHGiNAL v ^: Cl

As shown in Fig. 1, a storage capacitor 10 is aua a power supply unit, not shown, via a charging circuit 11 and a diode D ,. charged · The storage capacitor 10 is with the flashlight 12 a located in a chamber 13 surrounding the flashlight 12, connected to the laser (not shown) 14 switched · Sr has one of two parallel Secondary coils S- and Sg "existing secondary winding, which is connected in series between the capacitor 10 and one end of the flash lamp 12 · One of two in series switched primary coils P ^ and Pg "bootehonde primary winding is between a pulse source 15 and ground switched

To facilitate the presentation of the present invention, which essentially consists in the fact that the inductance of the triggering transformer is used to form the tron curve by suitable dimensioning of the inductance of the secondary apulses S 1 and S _{2, FIG. Shows the core of the transformer 14 together with the} Primary and secondary apules' in section · The core has two end absohnitta 16 and 1? made of a material of high saturation, including silicon steel, which are connected to one another by two core sections 18 and 19 made of a material of low saturation, such as ferrite.

When the transformer 14 is through one of the primary coils P ^ and Pg supplied pulse is excited to discharge to trigger the energy stored in the capacitor 10 in the flash lamp 12, the gas in the

V.

209808/1901
BATH ORIGINAL

Flash lamp 12 ionizes and a fine current begins to flow from the capacitor. After that, the voltage at capacitor 10 caused by the stored energy is able to maintain the ionization of the Gaaoo in the flash lamp 12 oo for a long time, "bia the stored energy for one Amount abainkt _t which is no longer sufficient to maintain the ionization.In order to obtain a suitable current curve, immediately after the ionization of the flash lamp 12, the inductance of the trigger transformer 14 must be reduced to a value that is correct for the formation of the discharge pulse.

In order to obtain the desired trigger course, the secondary spul ο dea transformer 14 assumes a first induc- to vitätawert _t is given by the slope of the curve in the diagram of Fig. 2 in the region of the current intensities between 0 and I * and for use during the ignition phase of the flash lamp 12 is determined. During the immediately following discharge period of the pulse shaper, the secondary coil assumes a second inductance word, which is indicated in the diagram by the slope of the curve between X ₄ . and I2 is characterized

"The section of the characteristic curve for the inductance of the secondary coil dea transformer 14 at currents between 0 and I ^ is determined by the high saturation of the for the End portions 16 and 17 of the core material used 'and the low saturation of the for the middle core sections 18 and 19 within the Dichtgowiokelton secondary apules S ^ and S ^ material used · as soon as the Transformer 14 has been triggered by a pulse from the pulse source unö the power line has grown so much

209808/1901

BATH ORIGINAL

int that eio is sufficient to saturate the core sections 18 and 19, then the entire core arrangement behaves like a core provided with an air gap and supplies the current strengths X * and Ig given in FIG Inductance, at the current strength I ", both the middle core sections 18 and 19 with the low saturation and the end sections 16 and 17 with the high saturation are saturated, and an inductance is obtained which is shown in FIG. 2 by the increase in the curve at I" exceeding current strengths is characterized · By the choice of the size of the capacitance of the capacitor 10 and the inductance of the transformer, the current is limited to a maximum value I _max below Ip, so that the capacitor 10 and the inductance of the secondary coils S ,. and Sg provide the appropriate current curve.

During the initial phase of the discharge cycle, the strength of the current flowing from the capacitor 10 via the secondary coils S ^ and Sp is less than I ^ and neither the high saturation material of the end sections 16 and 17 nor the low saturation material of the central core sections 18 and 19 is saturated . Therefore the stray field radiation is very low. As soon as the gas in the lamp 12 is ionized, the current strength rises rapidly to the maximum value Ij _10x.When the current strength exceeds the value I ^, the middle grain sections 18 and 19 of low saturation are saturated and thereby switch the inductance of the secondary coils S ^ and Sg ^{to the} correct value. Since the end sections 16 and 17 are still unsaturated, the stray field radiation at the ends of the saturated core sections 10 and 19 is low. Since the secondary "

209808/1901

BATH ORIGINAL

coil S ,. and Sg are tightly wound and tightly connected to the neighboring windings, only a small amount of stray radiation occurs on the sides of the saturated core sections 18 and 19.Although the middle core sections 18 and 19 are operated in saturation, around the flash lamp 12 To deliver the correct-shaped current _{t there is} only very little electromagnetic interference, because the tightly wound secondary coils S ^ and Sg limit the flux passing through the ends of the secondary coils S ^ and Sg.

From the foregoing it can be seen that the use of an annularly closed core made of a material with high saturation and tightly wound secondary coils reduces electromagnetic radiation from the secondary coils when these secondary coils are used as the sleeve of a pulse generator and in series between the Spoicherxondensator and the Load are switched, and that the core sections 18 and 19 located within the secondary coils, made of material with low saturation, provide the inductance necessary for the trigger transformer a primary inductance of 12 / WH and a secondary inductance of 4.8 mE developed during the sin phase. After the saturation of the central core sections 18 and 19, the inductance of the secondary coils S ^ and Sg sank to 75 / * -H. The material chosen for the middle core sections 18 and 19 was a 3 B 7 ferrite *

209808/1901,

BATH ORIGINAL

Eg projects that other uses another Require dimensioning and other © materials and other arrangements can be used to "meet special needs" without affecting the frame to leave the invention · So, for example the primary coils P * and P «instead of around the end sections 16 and 17 can be wound around the middle sections 18 and 19 of the coil core · You could also use the end sections omit if clii »middle kernel sections designed as a toroid and the secondary coils wound in this way are that the ends of one to the ends of the other to limit the magnetic flux to the toroid made of the material of low saturation after saturation of the core

In other embodiments of the invention, the Primary winding and / or the secondary winding consist only of a coil and it could be when using two coils the Roihon and the parallel arrangement of the Coils reversed compared to the embodiment shown or the coils of both windings could be connected in parallel or in series · The important thing The feature of this invention resides in that the lower saturation material of the core becomes saturated when the stored energy via the secondary winding and the flashlamp au begins to discharge, and that the material with the low saturation is completely enclosed by the tightly wound secondary winding «

If the ends of the secondary winding do not adjoin each other, these ends should be made of a material that is compatible with

209808/1901

BATH ORIGINAL

the maximum permissible discharge current is not saturated, , be sealed and gs noil aua this material for the magnetic flux a continuous' weighed from the one end to be created on the other · Accordingly, the secondary winding, which is the middle one, is the desired inductance determining during the discharge by the flash lamp Komabnohnitte surrounds, designed so that they the magnetic Flux maintains within the middle core sections while the field outside the secondary is in unsaturated Nuclear material is guided · These hateful actions result in a reduced radiation, and not only this is because the radiation from the pulse trigger transformer has been reduced, but also because a separate induction coil is no longer required

209808/1901

BAD ORJGiNAL

Claims (1)

Claims Pulse shaper with a storage capacitor, oinem trigger transformer, of which the secondary power is connected in series between the storage capacitor and the load, whereas its primary winding is connected to a pulse source, and one which is released by a pulse applied to the primary winding, from the storage capacitor to the load. flowing I discharge current limiting, between storage capacitor "and load switched inductance, characterized in that the secondary winding (S, j, S ₂ ) of the trigger transformer (14) is used as the series inductance itrani-fe-belbaa? and for this purpose at least one section (18 , 19) of the transverse format core consists of a material of low saturation and the inductance of the secondary winding (S 1, S ₂ ) is chosen so that when this core section (18, 19) is saturated, the discharge path has the desired course accepts. 2 · Pulse shaper according to claim 1, characterized in that the secondary winding (S ^ ₉ Sg) is tightly wound around the core section (18, 19) of low saturation, so that the secondary winding (S ^, S ₂ ) passes through the inner cross-section d © 3? Secondary winding limited "remains 5 · Pulse shaper according to claim 1 or 2, characterized in that means are present which the off «· Limit the spread of the field at the ends of the secondary winding (S ^, Sg). 09808/1901 BAD ORIGIN ^ TIC C Pulse shaper according to claim 5, characterized in that the ends of the basic door winding (E,., Qg) are closed by core cutouts (16, 17) made of a material of high saturation, which remain unsaturated even at the maximum value of the discharge current, and the ends of the secondary winding ( υ *, Q ^) form a continuous path for the magnetic field 209808/1901 BATH ORIGINAL