DE106680C - - Google Patents

Description

IMPERIAL

PATENT OFFICE.

The converter - rectifier are devices that enable alternating currents from any voltage to direct currents of any voltage or vice versa Direct currents of any voltage in alternating currents of likewise - any voltage to convert.

A converter - rectifier essentially consists of the following parts:

A. a converter containing:

ι. η primary circuits, which are subject to the action of η alternating electromotive forces, which have the same effective magnitude, but are successively reversed

- period shifted.
η

2. K secondary circuits, which must be the seat of two alternating electromotive forces which have the same effective magnitude,

but successively around - period

are shifted.

This 2 K secondary circuits are connected among themselves as well as the successive divisions of a DC machine armature, which is divided into K 2 detachments;

B. a synchronous commutator with 2 K webs, which, either directly or through the intermediation of slip rings and brushes, are connected to the connecting wires of the 2 K secondary circuits as well as the webs of the commutator of a DC machine with the connecting wires of the successive departments their anchor.

If, under these conditions, the number of alternating currents that one wants to transform is equal to α , and if a synchronous motor gives the commutator or the diametrically opposed brushes grinding on it a speed of α revolutions per second, then one can external, draw a direct current from the circuit branched off by the brushes.

In a converter rectifier that has 2 K secondary circuits, the current reversal takes place under the following conditions, if one disregards the conversion coefficient.

1. When there is no leakage in the converter.

The phenomena of commutation will be the same as those which occur with equality of the electrical work supplied in a machine, which is obtained by converting the polyphase alternating current machine or machines which feed the converter-rectifier into direct current dynamo machines and for the purpose their anchors divided into 2 K equal compartments.

2. In reality the coefficient of self-induction must be of each of the divisions of the machine obtained in this way can be increased by a supplementary coefficient which Dispersion of every secondary circuit of the converter, and at the same time the

The resistance of these divisions can be increased by that of a secondary circuit.

From this arises the need to build the converters in such a way that as little as possible Scatter can occur.

In the devices of this type, which the inventor has already pointed out, the number is of the magnetic cores and the primary circuits of the converter equal to the number of the multiphase currents which one wishes to make usable, and this number is necessary limited. In practice it is 3 in the case of three-phase currents and 4 in the case of four-phase currents.

In this way one is led to find the devices for great performance from one to form a small number of large parts, the scattering of which reaches a high value, whereby the turnaround becomes difficult.

For this reason the inventor has devised a new device, on the contrary allows a converter-rectifier to be formed from a large number of small parts, in which the spread is very small.

Assume that one has three electromotive forces H ¹ H ² H ³ of the same effective magnitude, but their changes

Phase differences equal - present period. One sets:

H ¹ = H sin 2 π at; H ² = Hsin 2 π j at + -);

It is a matter of bringing about 2 K electromotive forces of the same effective magnitude in 2 K separate secondary circuits, but which, however, follow one another

Period are shifted so

2.K

z. B. like the following:

h ^l - h sin 2 π at; h ² = h sin 2 π I α t

=: / jsin2 π [at - \ -

2 Κ— I
2 K

Each secondary circuit is formed by three separate coils which are connected in series and each of which has a constant number γ of turns.

In Fig. Ι the drawing, these coils are shown schematically at abc. Each of them surrounds one of the magnetic nuclei xy \.

These cores also carry primary circuits m ρ q, which are connected between the three sources of the electromotive forces H ¹ H ² H ³ and a neutral point ο .

The number of turns of these primary circuits is determined in such a way that, if one uses e ^x e ² e ^{8 to} calculate the electromotive forces that are generated in each turn surrounding the core χ, the core y and the core \ , and with ε and β denotes two constants, can set:

e ¹ = (ε sin 2 π β) sin 2 π α f,

I ε sin 2 π I β A 1 sin 2 π I at A

3 / J I 3

= ε sin 2 7Γ j E
= ε sin 2 π Ι β

ι / ² \ I · / ²

I ε sin 2 π [β A 1 sin 2 π I at A,

Under these conditions comes the one developed in the secondary circuit under consideration electromotive force the following expression to:

e = y [e ¹ + e ² - (- e ³ ] = y ε
Now is

sin 2 π α t sin 2 π β + sin 2 π (α t A. 1 sin 2 π I β A I +

V 3 / I 3

/ 2 \ / 2
sin 2 π α t A sin 2 π β Η

I 3 / I 3

sin 2 π at Ar sin 2 π β = - cos 2 π (at - β) - cos 2 π (α t Ar β)

sin27r (a £ H \ A- sin 2 π Iß Ar ■ - I = -

\ 3 / \ ^3/2

-t-sin27r | ßH) = -

cos 2 π (at - β) - cos 2 π I α f + β Η

/ 4

cos 2 π (α t - β) - cos 2ττΙαί + β + -

cos 2 7Γ (a t A- β) + cos 2 π I a t + β A- 4- j + cos 2 π (at A- β A- - j = ο,

From which follows

e = - γ ε cos 2 π (at - β).

If one passes from one secondary circuit to the next, β is on

following each other by the same size - ψ

change, then these 2 K circuits become the seat of electromotive forces, which have the same effective magnitude, but

are shifted consecutively by- ^ r period.

The number of turns N ¹ N ^ N ^S , which are to be given to the various primary circuits, which act on the coils of a secondary circuit, is determined as follows:

If φ ¹ φ ² φ ³ denote the largest values of the lines of force developed in the nuclei χy \ (Fig. 1), one has

e ¹ = 2 πα φ ¹ sin 2 πα t,

e ² = 2 π α φ ² sin 2 π I α t - \

= 2 π α φ ³ sin 2 π Ι α ί Η

On the other hand, it is

2 π α ψ ¹ Ν ¹ = Η,
2 τι- α φ ² iV ² = H,

From the above equations one obtains after eliminating the quantities e ^l e ² e ³ and φ ¹ φ ² φ ³

N ¹ = -r

ε sin 2 π β '
Ν ³ = -

β + -I

ε sin

ε sin 2 7Γ (β

If sin 2 π β = ο or sin 2 π

or sin 2 π β - | | = ο would be so must

V 3 /

you give the corresponding primary coil an infinite number of turns, but since the the secondary coil belonging to it, the seat of an electromotive force should be equal to zero, so one simply becomes this coil, as well as its magnetic core and the primary coil leave away that would excite him.

Each secondary circuit must therefore be surrounded by three separate magnetic cores each equipped with a special primary circuit. The numbers of the in Lines of force developed by these three nuclei will be transformed according to a sinusoid law change when moving from one core to another.

In all the cores whose primary electromotive circuits are from the same source Power are supplied, the numbers of the lines of force developed in it also change a sinusoidal law.

The cross-sections of these nuclei are of course proportional to the number of lines of force change.

One can also note that the secondary circuit of the ordinal number (n - \ - K) must always be the seat of an electromotive force which is the same as that of the circuit of the ordinal number n, but has the opposite sign. So it will be possible to let the thin magnetic cores act on these two circuits by simply making sure to wind one in one sense and the other in the other. In this way it is only necessary to use 3 K separate magnetic cores in place of 6 K cores in order to excite the 2 K secondary circuits.

In the foregoing, only the most frequent case was dealt with, where one can deal with Three-phase currents, but the same method extends directly to the

Case where one changes over ρ by - period

P.
pushed currents.

One then has to let separate magnetic cores act on each circuit ρ , which develop electromotive forces in each winding surrounding them, namely

e ¹ = ε sin 2 π β sin 2 π at,

ι
P.

e ² = ε sin 2 π β -1 sin 2 π I at ■

eP = ε sin 2 π

V - ι \ 7 V-

+ I sin 2 ar I α ί -f ■

where you get the size β every time you go from one secondary circuit to the next passes over to - must change.

The various magnetic cores that go to form a converter rectifier, can be grouped among themselves in infinitely different ways. In the following a device with 48 secondary circuits is described as an example only has and with three-phase alternating currents of 6000 V single voltage and from the Alternating number 90 fed a direct current of 1600 A below the voltage of 250 V. can.

ι. Cross section of the magnetic cores. .

The calculation shows that it is the largest The value of the electromotive force developed in each secondary circuit is equal 17.05 V must be.

Each of the secondary circuits is given two turns, and the largest specific one is made Induction in each of the magnetic cores is equal to 6000.

Because you have to wind two secondary circuits around each core. so you have to have 3 X 24 = 72 separate cores.

Their real cross-sections in Quadratcentimetern ^Z1 / ^2. . ../ ²⁴ one gives zweckmäfsig the following values

f ¹ = ο qcm, P = 213 sq cm, / • 13 301 sq cm, P ⁰ = 21 3 qcm / ■ 2 40 - P = 239 - / 14 _ 298 - P ¹ = 184 - P = 78 - P = 261 - / ¹⁵ = 291 P ² = 151 P ~ 115 / 'ο. = 278 - / ;; = 278 - Λ23 115 P = 151 P ¹ = 29 '- 261 / • 24 78 - P = 184 - / ¹² = 298 - / • 18 239 - 40 -

2. Nature of the grouping of these nuclei.

To any mutual induction between the electromotive sources from different sources To avoid force branched primary circuits, only the cores are below magnetically connected, which is the seat of changes in the lines of force of the same phase will be.

On the other hand, in order to reduce the length of the connecting wires, it is advantageous to turn on one side of the rectifier half of the secondary circuits and on the other Side to arrange the other half of these circuits.

This leads to the cores being arranged in six parallel rows. To the device The twelve nuclei do not give too great a length in proportion to their height each row arranged in pairs one above the other.

In this way, the arrangement shown in the diagram in FIG. 2 is obtained.

The upper nuclei are indicated by circles of smaller diameter, while the larger circles concentric to them represent the lower nuclei. The two Numbers in circles give the cross-sections of the corresponding cores in square centimeters at.

FIG. 3 illustrates the magnetic framework which is formed by the cores shown in FIG. 2, their connecting pieces dd and the outer cores ee, ee . The lines of force developed in the inner nuclei close in the connecting pieces d and cores e.

The numbers in this FIG. 3 again mean the cross sections of the corresponding cores in FIG Square centimeters.

In order to limit the cross-sections of the connecting pieces dd and the outer cores ee to the smallest extent, it is presupposed that the lines of force developed in the cores of each column are in one direction in the number of even columns and in the number in the odd columns in the run in another direction. The course of these lines of force is indicated in Fig. 3 by arrows. In this way, only the differences and not the sums of the lines of force will pass through the connecting pieces dd and the cores ee , which makes it possible to greatly reduce their cross-sections and the hysteresis losses of which they will be located.

This result is obtained by taking all the primary coils of those nuclei which are represented in FIG. 2 by the circles hatched in one direction, to the right winds and all the primary coils of the cores shown in Fig. 2 by those in the other Direction of hatched circles are shown, wraps counter-clockwise.

3. Primary circuits.

The number of turns of these circuits change with the cross-sections of the cores, which surround them. Since there are cores with 12 different cross-sections, must you have primary circuits with 12 different numbers of turns.

On the other hand, there is the number of ampere-turns developed by each secondary circuit is the same, and since each primary circuit always has a number of ampere-turns must develop which is very similar to that developed by the secondary circuit that covers it, but which is opposite Has signs, it will be the strength of the current in each primary circuit inversely proportional to its number of turns. So it is advisable to check the cross-section of the conductor to change when going from one circuit to another.

The following table gives the number of turns of the primary, the nuclei of the given Cross-section of surrounding circuits,

the diameter of the wire to be used for the winding and the number of similar circuits which the device contains.

Winding By number of cross-section number of knife similar the primary the around Circuits
in the Cores current coiled whole before circle Wire direction Turns 40 sq. Cm II 352 0.7 mm 6th 78 - 5 736 0.9 - 6th "5 - 3,900 1.1 - 6 · 151 - 2 976 1.2 - 6 ' 184 - 2436 1.4 - 6th 213 - 2 100 1.5 - 6th 239 - ι 872 1.6 - 6th 261. i ₇ i6 1.6 - 6th 278 - ι 614 ^J j7 - 6th 291 ¹ 536 !, 7 - 6th 298 - ι 500 1.7 - ■ 6th 301 ι 488 !, 7 - 3 ·

4. Secondary circuits.

From Fig. 2 it can be seen that the three cores which make up every secondary circuit should excite, are arranged in the same line perpendicular to lines I, H, III ... VI.

Four turns must be put around each of these groups of three cores, of which two have a secondary circuit and the other two have the other secondary Form circuit.

For this purpose one takes two copper bands, which are insulated with one Body separates, and bends it as shown in FIG.

If one of the cores to be surrounded has a cross-section of zero, then it is bent Copper strips in the case where the central core must have a cross-section of zero, so, as FIG. 7 illustrates.

In this way you have two turns.

Two similar systems (Fig. 6) are placed one above the other and the narrow sides of the copper strips are separated by an insulating body fg.

The ends of the lower bands are arranged as indicated in FIG. 4, the ends of the upper bands as shown in FIG. 5, or vice versa. If the ends of the strips shown in FIG. 4 are designated by h ij k and the ends of the strips shown in FIG. 5 by Iqr s, the following connections are made in all cases by means of vertical copper strips (FIG. 6):

The end i is connected to the end r and the end j to the end q .

The ends Z and r are extended downwards when the bands of Fig. 5 are on the upper part, or extended upwards when the said bands are on the lower part.

Any vertical ribbons used to make the connections or the ends of the horizontal ligaments are separated by insulating bodies and by insulated bolts firmly pressed against each other.

It can be seen from FIGS. 4, 5 and 6 that in this way two circuits with two Has formed turns around the three cores surrounded by the horizontal bands.

The first circuit starts at the end h and ends at the end s ; it winds around the kernels from left to right.

The second circuit starts at the end k and ends at the end Z; it winds around the kernels from right to left.

The scheme Fig. 2 shows how the various secondary circuits are among themselves must be grouped. To make this scheme clearer, it was assumed each of these secondary circuits would only have one turn.

This diagram also shows how the branches for drawing electricity are arranged have to.

It will be noted that all connections and branches along the devices containing the magnetic cores of the rows I and IV, are arranged.

Fig. 8 shows the appearance, which the side with the magnetic Cores of the series I of FIG. 2 formed device presents the opposite Rectifier lies.

Figure 9 illustrates a rectifier similar to that used by the inventor used their first converter rectifiers (see patent specification no. 78825). One can however, replace this rectifier with a different one.

This rectifier is placed between rows I and IV of the diagram in FIG. Its power connections follow one another in the same order as those the converter, so you only have the power connections of the converter and the rectifier, which are opposite to connect with each other.

Claims (2)

Patent Claims:
i. A converter for converting η primary, η shifted by - period Multi-phase currents of any voltage secundä're in K to - == period verschlebene multiphase currents of arbitrary voltage or, conversely, formed of K secondary circuits, all of which have the same number of turns and of which surrounds each η magnetic cores, in which by means of η primary circuits η separate power line hosts are developed whose Changes in relation to time are the same for successive phase differences - Present period, whereby the win n extension number of primary circuits, which determine the path of these lines of force from a core changes to the other in such a way, that the numbers of developed in these cores η power lines to each other act as the numbers sin ß, sin Iß + / ² ? Λ. f β 4- ··· sin ß + \ ^η L. 2 7Γ where β is a constant means further wherein, when one passes from one of the K secondary circuits to the next, the primary circuits which each of η to the new secondary circuit acting cores surrounded, are prepared in the manner, that the numbers of Lines of force developed in these nuclei are related to one another like numbers Si _n Ti ₆₊ ^ in which expressions the values between the brackets are used each time then around 2 π must increase if one transitions from a secondary circuit to another, wherein when i the above expressions for each secondary circuit, 2 .... η numerirt and designated by the same numbers, the cores, which are the seat of power lines corresponding strength, the primary circuits of the K cores, which belong to the K secondary circuits with the same numbers, are in the by-line to the same source of electromotive force. 2. Converter according to claim ι for converting multiphase current into direct current and vice versa, characterized in that the K secondary circuits of the converter are grouped among themselves and to the successive webs of a commutator as well as the successive departments of one in K departments split DC machine armature. For this purpose ι sheet of drawings.