DE1282686B - Pulse generator for generating one or more sequences of time-shifted pulses - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. Cl .:

H03k

German class: 21 al - 36/02

Number: 1 282 686

File number: P 12 82 686.7-31 (J 26735)

Filing date: October 21, 1964

Opening day: November 14, 1968

The invention relates to a pulse generator for generating a sequence or simultaneously several sequences of temporally staggered impulses with a given repetition frequency, with a number of transformers whose cores are at least partially made of ferromagnetic Material with an approximately rectangular hysteresis loop, the primary windings with variable current of an amplitude that leads to the magnetic saturation of the ferromagnetic material with the approximately rectangular hysteresis loop is sufficient, are fed and each at least one Have secondary winding, from each of which a pair of pulses is taken per period, the Pulse pairs of the individual transformers can be combined to form a pulse train.

The generation of pulse trains with always the same base frequency with selectable successions different pulses of adjustable height and duration within a period can be used in television technology for multi-channel transmissions, automatic controls, digital calculators or many other uses may be of use. The impulses should go from period to period in occur in the same sequence. Also the possibility of generating several of each other at the same time independent pulse trains of the same repetition frequency is important here.

It is already known to use transformers whose cores are made from to generate such pulses consist of a material with an approximately rectangular hysteresis loop. Becomes such a transmitter fed on the primary side with a periodically changing current of sufficient amplitude, im leads During this change in current, the induction in the transformer core changes almost suddenly from one state of saturation to the opposite. During this jump becomes secondary induces a voltage spike that can be used as a pulse. A periodic primary current thus alternately results in positive and negative secondary impulses.

For example, a transformer is known (British patent specification 915131) which is fed with a sawtooth-shaped current and whose core is divided at one point into numerous parallel magnetic flux branches which, as the current gradually increases, are remagnetized one after the other according to their geometrical arrangement and each of which in its own secondary loop generates an impulse. The result is a pulse sequence that is dependent on the geometric properties of the core in question, since the pulse generator is used to generate an or
several sequences of time-staggered impulses

Applicant:

Institut za Automatu i Telekomunikacije
"Mihailo Pupin", Belgrade

Representative:

Dipl.-Ing. H. Leinweber

and Dipl.-Ing. H. Zimmermann, patent attorneys,

8000 Munich 2, Rosental 7

Named as inventor:

Dipl.-Ing. Marko Petrovic, Belgrade

Claimed priority:

Yugoslavia of October 21, 1963 (834)

Moment of magnetization reversal with increasing current from the magnetic voltage of the through This magnetic flux branch laid induction line path is determined. However, this pulse generator has the disadvantage that it can only be expanded with great effort and given requirements can be customized. In particular, the core would have to be the most favorable, for example Ferrite core is manufactured as a mass-produced item, specially designed according to each pulse program will.

Furthermore, a pulse generator is known (British patent specification 854 558) in which the transmitter from Sinus current are fed and also have a direct current bias winding, with the help of which the zero line of the sinusoidal current can be shifted, so to speak. This allows the Dependence of the magnetic field strength at which the core is remagnetized on the sinusoidal Feed current can be set within certain limits. In the range of the sine amplitudes

809 637/1166

However, if an exact setting is no longer possible, the sequence of the output pulses achieved is no longer possible, borrowed, especially since both the shifted zero is the unit of the pulse generator, so the line as well as the underlying part of the sine wave transformer, so small and simple that it can be used in large wave of the primary stream must still be sufficient, number to almost any programs together to generate the magnetic reversal field strength. 5 can be switched.

The sinusoidal and direct currents also come from The multi-phase primary feed is preferably

independent power sources, e.g. B. one wise with sinusoidal currents, since these on an oscillator and a battery, which are available for temperature experts and for superimposition Change slightly different change characteristics - again result in a sinusoidal current. Insstics may have, so that the pulse generator io special can be advantageous with the transformer is temperature sensitive. Two-phase current are fed, for example

Finally, a pulse generator is known to have a mutual phase shift of π / 2 . (German patent specification 1 073 221), in which different primary windings, in particular a sawtooth current, are connected in series, fed and fed Primary windings with each other A ease of adjustment and the

have different number of turns. When eliminating possible repercussions of the core rise of the current is the transformer with the magnetization reversals is possible because of the highest number of turns as the first to be remagnetized and the core of the transformer in an actual transducer with the lowest number of turns as the last 20 formator core that carries the primary windings, and ter magnetized. The successively occurring a switching core is divided, which is made of the material Pulses are generated by the secondary windings with the approximately rectangular hysteresis loop Transformer tapped. With a fine subdivision and with the transformer core by a the period duration for numerous pulses results in coupling winding is connected. Here can the here the difficulty that on the transformer 25 actual transformer core, for example a lot of primary turns must be wound - consists of ordinary transformer sheet, sen, since such a magnetic characteristic is given with a few primary windings impulses Shifts can only be found in certain coarse steps that the corresponding inductances of the Depending on the number of turns, primary wires wound around these transformer cores can be selected. In addition, according to the principle of this 30 windings are already used to maintain the sine pulse generator sufficient for the cores of the transformer mate- rial of the feed currents. Further results rialien required, although an approximately rectangular, has the advantage that the switching core, its magnejedoch The widest possible B-H loop, that is, an erratic tilting behavior is used, less substantial coercive force. If the shape changes, windings must carry and thus greater freedom the B-H loop is based on the temperature for its size. In particular fluctuations, so the time sequence also changes, which is favorable for very small switching cores Impulses. A magnetically soft material with very coupling winding from only one of the magnetic fluxes However, the narrow B-H loop is completely un- common in the transformer core and in the switching core reversible, since with such the transformer to form all encompassing turns. This turn would be remagnetized almost simultaneously. 40 must have a strong conductor diameter,

The invention is therefore based on the object, but does not require strong insulation. Benefits one Pulse generator of the type described too liable, the switching core carries the secondary winding, With moderate effort, a very fine development, but this can also be based on the transformer subdivision the repetition period for the kern sit.

The time of occurrence of the impulses and the observing 45 To expand the program of the impulsive These occurrences largely disturbance generator, it is possible to at least part of the is insensitive. Transformers with several secondary windings

According to the invention, this task will be carried out, each with different impulses Pulse generator solved, in which the primary outputs are connected. Here it is again windings of the individual transformer currents are possible, each with the same pulse separator Phase are fed and the secondary windings connected to the winding outputs are backed up the primary windings of the individual transformers. Of course you can ger according to the desired phase shift also, for example, the different secondary colors the output pulses are selected. windings to different primary windings of one

A magnetic standard output transformer is connected in the cores of the transformers field effective, the phase position of which depends on the ampere. By suitable combination of several Number of turns of several, of different-phase secondary windings, which may be different depends on the primary windings flowing through. The dene number of turns and different winding directions The number of turns ratio is in very fine gradation, any desired pulse can be selected. Especially when a core material with 60 sequence is removed.

If a narrower hysteresis loop is selected, the Further advantages, details and features of the

Magnetization reversal immediately after the zero invention result from the following description pass the entire exciting flow. exercise. In the drawing, the invention is exemplary-Im Case of the use of sinusoidal primary manner illustrated, namely shows flow, the zero crossing is very precise same point in time. A certain temperature-dependent transformer whose switching cores are directly excited speed of the hysteresis loop and the other current and time diagrams of the alternating currents and the gyro element has only a minor influence on the time-generated pulse sequences,

5 6

F i g. 2 a schematic representation of an over-induction in the nuclei by leaps and bounds from a saturation

carrier with indirect supply to the switching cores, the state of the switch changes to the opposite. These

F i g. 3 a modification of the transformer according to sudden induction changes happen about

F i g. 2. at the time of the zero crossing of the exciting

In Fig. 1 is a pulse generator with five floods. Shown during this sudden changer. Each of the transducers has a gene in the secondary windings electrotorroid-shaped core 1, 2, 3, 4 or 5 from a motor force in the form of narrow, short-lasting material, which generates an approximately rectangular, pulse, the duration of the change time of the narrow hysteresis loop owns. All wick induction is the same. During the alternating current windings of the individual transformers, two respective cores are wound in each secondary winding during this period T. The nuclei generally have pulses of opposite polarity. The general two primary windings N- and N " . Exciting flux is the vectorial sum of the The general number" / "means the two partial fluxes from the coils N ₁ ' and voltage number of the respective core. On N". Since, because of the series connection, the core 1 is the primary windings N ₁ ' and 15 currents /' or / "in all coils N / or N" N ₁ ", on the core 2 the primary windings N ₂ ' and are the same, the desired phase angle of N ₂ "is wound on the core 3 only one primary winding N. _A ' resulting flux through the ratio of etc. Turns w (N {) : w (N ₁ ") given on a core.

The number of turns of the primary windings N _t ' becomes the phase angle of the resulting exciting and N " are generally on the same and on ver ao flow designated as φ _ί and w (N) is a different cores different. Likewise assumed maximum number of turns one can her Winding direction or its connection direction around the primary winding, then be calculated when reversed, as the primary windings N ₁ " and N _r " flow / 'and / "show the same amplitude and one. Phase shift of π / 2 the number of turns

The primary windings Nf are connected in series 25 WiV ') = w (N) sin «·

and represent part of a circuit between a ^

AC source P 'and earth. The other w (N ") = w (N) cos φ-

Primary windings N "are also overall in series ''

switches and establish the connection of a change from the sign of the result

Current source P " with earth. The current sources P '30 the winding direction or the connection direction of the

and P ″ provide the respective primary winding phase-shifted from one another. The angle φ _ί is

Sine currents / 'and / ", which through the corresponding through the time of the corresponding output pulse

Primary windings flow. In the diagram of FIG. 1 of this transformer is determined in the pulse train.

is above the time dependence of the currents / 'and / "When connecting a number of seconds

shown. Both currents have the same amplitude. Each secondary winding now supplies it

and are phase shifted by π / 2 with respect to one another. Pulse pair for the corresponding common output

T indicates the alternating current period. corridor. At this the pulse sequence results from the

The cores 1 and 3 each have three and the temporally offset from one another, depending on the winding cores 2, 4 and 5 each have two secondary windings with a number of amplitudes differing from each other, also possibly provided two turns. However, the cores 40 can have different characters and pulse durations any number of secondary windings with the same impulses. Suitable combinations of or with different numbers of turns. Secondary windings can thus generate any impulse trend one end of each secondary winding is grounded, follow is to be achieved.

the other end an output S ₁ , S ₂ , S ₃ , S ₄ The pulses do not occur exactly at the time of

or S ₅ supplied. Next to each of these outputs is 45 zero crossing of the exciting flow,

in Fig. 1 in diagram form the detachable for this purpose but with a slight delay due to the

Pulse sequence shown. Coercive force of the magnet material. Changes

At the output S ₆ is a series connection due to significant temperature changes

Secondary winding of the first transformer and a hysteresis loop of this material, so does this

Secondary winding of the third transformer, the latter 50 essentially only on the intensity of the pulses

with reversed connection direction, led out. and only to a small extent, according to the

With the output S _{7 there} is a series connection of the delay after the zero crossing of the

Secondary windings of all transformers excitation, based on their time of generation. These

bound, with the secondary winding of the super-small time shift being the same for all pulses

tragers 4 is connected with reversed ends. 55 and therefore does not appear in their relation.

The information received at these outputs S ₆ and S _{7 may} , under certain circumstances, be desired to

Pulse sequences are also to be used in diagram form with regard to the point in time

posed. adjust their output pulses within certain limits.

The cores are made of ferrites or are made from a bar. This can be achieved, for example, through the magnetically soft ferromagnetic material with permanent magnets, which produce the cores of approximately rectangular hysteresis loops. You premagnetize the transformer. These permanent magnets can consist of the same or different materials directly as adjusting screws, which in particular has an influence on the be formed.
Pulse duration is. The stability of the temporal distribution of the impulses

The circuit arrangement according to FIG. 1 works 65 depends on the stability of the primary circuits,

in the following way: which is distortion-free and of more constant

The switching cores 1 to 5 have sufficient amplitude and a constant phase difference

strong alternating currents excited, so that must remain.

Of course, instead of a two-phase supply of the pulse generator, a other number of phases, in particular three phases, are used.

It is easy if some or all of the elementary transformers are to be able to be switched on or off contactlessly by providing a switchable or switchable strong direct current bias on the Transformer cores possible.

F i g. 2 shows the indirect magnetic excitation of a switch core i. This excitation takes place via a transformer Ii and a coupling winding 6 z ", which consists only of a common loop around the magnetic flux path of the transformer and that of the switching core. The primary windings JV / and N" are wound onto the core of the transfermator Ii. The switching core has a secondary winding 10.

The way this circuit works is as follows:

The transformer according to FIG. 2 with the transformer 7 z and the switching core i takes the place of one of the transformers in FIG. The transformer Ti is excited by the primary windings N { and N ", while the coupling winding 6i represents the secondary winding of the transformer Ti and the primary winding of the switching core ζ. The connections of the primary windings N { and N" and the secondary winding 10 correspond to the corresponding connections in the shuttering according to FIG. 1.

The coupling winding 6i must have a relatively large conductor cross-section, since it carries a considerable current. The phase of this current through the coupling winding 6 i is dependent on the phase of the resulting exciting flow through the transformer Ti. The core of the transformer 7 i can be made from standard elements, for example from ferrite or transformer sheet.

This design of the transformer frees the switching cores from the primary windings, which is particularly important for small switching cores. The winding of the primary windings on the cores of the transformers 7 ζ does not cause any difficulties. The primary number of turns can easily be selected to be relatively large, so that a certain number of turns ratio can be achieved with good accuracy. _g0

F i g. 3 shows a modified embodiment of the transmitter according to FIG. 2. In this transformer, a secondary winding 11 is wound on that leg of the transformer 7 / which also carries the coupling winding 6i for coupling the transformer Ti to the switching core i . The switching core i itself is penetrated only by the single turn of the coupling winding 6i. This solution can be used if, for example, the secondary winding 11 used has many turns which would be difficult to accommodate on the small switching core i. In this version, however, except the impulses also induced in the secondary winding 11 is still a small sinusoidal back EMF because vallen in the long programmable time ^ _5, during which the switch core i is saturated, the feedback winding 6i does not act like a complete short-circuit winding.

Claims (12)

Patent claims: 1. Pulse generator for generating a sequence or simultaneously several sequences of temporally offset pulses with a given repetition frequency, with a number of transformers whose cores are at least partially made of ferromagnetic material with an approximately rectangular hysteresis loop, whose primary windings with variable current of an amplitude that sufficient for the magnetic saturation of the ferromagnetic material with the approximately rectangular hysteresis loop, are fed and each have at least one secondary winding, from which a pair of pulses per period is taken, the pulse pairs of the individual transducers can be combined to form a pulse train, characterized in that the primary windings (N ₁ ' and N {') of the individual transformers (1 to 5) currents (/ ', / ") of different phases are supplied and the number of turns of the primary windings of the individual transformers according to the desired phase shift d er output pulses are selected. 2. Pulse generator according to claim 1, characterized by feeding the primary windings (Ν /, N ") with approximately sinusoidal phase currents (/ ', //"). 3. Pulse generator according to claim 1 or 2, characterized in that the transformers are fed with two-phase current (/ ', J ") and the primary windings (N {, N") connected to the same phase are connected in series. 4. Pulse generator according to claim 2 and 3, characterized in that the two current phases (/ ', I ") are phase shifted from one another by π / 2. 5. Pulse generator according to one of claims 1 to 4, characterized in that the core (1 to 5) of the transformer is divided into a transformer core (7 z) which carries the primary windings CiV /, N ") , and a switching core (i) which consists of the material with the approximately rectangular hysteresis loop and is connected to the transformer core (7 z) by a coupling winding (6 z). 6. Pulse generator according to claim 5, characterized in that the coupling winding (6i) consists of a turn which jointly encompasses the magnetic fluxes in the transformer core (7 z) and in the switch core (z). 7. Pulse generator according to claim 5 or 6, characterized in that the switching core (i ) carries the secondary winding or windings (10). 8. Pulse generator according to claim 5 or 6, characterized in that the transformer core (7 z ") carries the secondary winding or windings (11). 9. Pulse generator according to one of claims 1 to 8, characterized in that at least some of the transformers have a plurality of secondary windings (10, 11) which are each connected to different pulse outputs (S ₁ to S ₇ ). 10. Pulse generator according to claim 9, characterized in that in each case the secondary windings (10, 11) connected _{to the same pulse outputs (S 1} to S _{7) are connected in series.} 11. Pulse generator according to one of claims 1 to 10, characterized in that the secondary windings (10, 11) sometimes have different numbers of turns. 12. Pulse generator according to one of claims 1 to 11, characterized in that the ferromagnetic material used 10 approximately rectangular hysteresis loop has a very narrow hysteresis loop. Documents considered: German Auslegeschrift No. 1073 221; British Patent Nos. 915131, 854 558. 1 sheet of drawings 809 637/1166 11.68 ® Bundesdruckerei Berlin