DE4136176A1 - Toroid thrush - Google Patents

Description

Technical field

The invention is based on a toroidal choke according to the preamble of claim 1.

State of the art

With the preamble, the invention takes on a state of the Technology reference, as it comes from the Swiss company magazine: Brown Boveri Mitt. 12 (1978), pp. 777-785. There is a toroidal air choke coil shown which has a medium inductance and with a strong Harmonic current is resilient. Such Chokes are used as swinging and quenching chokes in Power converters of local vehicles used.

For short-circuit currents in the order of 100 kA 140 kA, as is the case in high-performance converters as a result of Ignition can occur, is such a choke not suitable. Such short-circuit currents can, for. B. occur when in a bridge circuit 2 at the same Phase associated semiconductors unwanted or defective ignite simultaneously and thus the intermediate circuit capacitor of a converter with a DC link short circuit.

Presentation of the invention

The invention as defined in claim 1 solves the task of a toroidal choke of the type mentioned To develop in such a way that it is suitable for flows of 100 kA can be used with a minimum volume and has small losses.

An advantage of the invention is that the Segment choke from a variety of segments one Toroids or ring beads after assembling the turns can be connected in series or in parallel. Leave it relatively stable segments with high current carrying capacity use that do not have to be windable. So that leaves high mechanical strength of the toroidal choke to reach. The toroidal choke is easy to use assemble while ensuring a high Short-circuit strength.

A given installation volume can be better used the geometry of the toroidal choke being very precise is reproducible. The number of turns and thus the The inductance of the toroidal choke can be easily changed or adjust.

When using a pressure bandage or a steel ring around the toroidal choke can do that for the segments used copper up to several times its yield point claim.

A high one can be used for the segmented toroidal choke Filling factor with a large passage area for the magnetic field with minimal leakage.

A modular throttle design is by choosing more or fewer turns or radially offset Turns possible.  

The chokes can be rectangular on the outside. Natural or an oil cooling with forced circulation are possible.

Brief description of the drawings

The invention is illustrated below with reference to embodiments play explained. Show it:

Fig. 1 a section of a Toroidal inductor shown in perspective of prefabricated partial windings,

Fig. 2 shows a modular choke structure in the cutout with radially staggered partial windings,

Fig. 3 is a rectangular limited on the outer circumference Toroidal inductor in the cutout,

Fig. 4 is a partial winding of a Toroidal inductor with angled connecting elements,

Fig. 5 is a winding element having Mehrfachwindung,

Fig. 6 is a Winkelprofilwindung,

Fig. 7a and 7b, a winding element made of wire,

Fig. 8 is a segment throttle in plan view,

Fig. 9 is a vertical section through the throttle segment of FIG. 8 with pressure bandage and clamping plates,

Fig. 10 is a segment of the segment reactor according to Fig. 8 in a perspective view;

Fig. 11 is an insulating film of the segment reactor according to Fig. 8 and

Fig. 12 shows a section of a partial winding in a flat design.

Ways of Carrying Out the Invention

In Fig. 1, ( 1 ) denotes a partial toroidal choke, which is constructed from a plurality of U-shaped winding elements or segmented partial windings ( 2 ). The partial windings ( 2 ) are arranged in a ring around a central, cylindrical recess ( 6 ) and each have a lower leg ( 2 a) and an upper leg ( 2 b). At the inner edge ( 4 ), the partial windings ( 2 ) have a width a that is smaller than a width b on their outer edge ( 5 ). The two legs ( 2 a, 2 b) have a height c near the inner edge ( 4 ) which is greater than their height d on the outer edge ( 5 ). The widths a and b are dimensioned so that the available volume for the toroidal choke ( 1 ) is used well. The associated heights c and d are dimensioned such that a current cross-sectional area through each partial winding ( 2 ) is the same or does not deviate from an average or desired current cross-sectional area by more than 30%, preferably not more than 10%. On the outer edge ( 5 ) of the upper leg ( 2 a) of a partial winding ( 2 ) with the outer edge ( 5 ) of the lower leg ( 2 a) of an adjacent partial winding ( 2 ) by means of an electrical connecting element ( 3 ) made of copper z. B. electrically connected by soldering. Such electrical connecting elements ( 3 ) connect the individual partial windings ( 2 ) to form a single toroidal turn or connect them in series. The toroidal choke ( 1 ) has 360 / β partial windings, where β denotes a segment pitch angle measured in degrees.

Fig. 2 shows partial around a central recess (6) a plurality of circularly arranged, separate segmented sub-windings, wherein mutually adjacent sub-windings (7-9) have in the radial direction a different length (1). Such a staggering enables a high element density or number of turns of the toroidal choke ( 1 ) to be achieved. In this way, a high fill factor can be obtained with a large conductor cross section.

Fig. 3 shows a detail of a toroidal choke ( 1 ) with a plurality of partial windings ( 10 ), which have different lengths in the radial direction and rectangular boundaries along the perpendicular edges ( 11 , 12 ) on the outer edge. In this way, the toroidal throttle ( 1 ) can be adapted to a predetermined volume. It is understood that the outer boundary z. B. 5-sided, 6-sided, etc. could be selected.

Fig. 4 is a U-shaped shows partial winding (13) with 2-symmetrical, angled connecting elements (13 a, 13 b) having an inside angle (α) in the range of 90 ° -150 °, preferably in the range of 100 ° -130 ° enclose between themselves. Such partial windings ( 13 ) can, for. B. consist of aluminum or copper, made as flat sheet metal cuts and, if necessary, used in two layers.

Fig. 5 shows a partial winding or a winding element ( 14 ) with several serpentine windings arranged one above the other, which are mutually insulated by means of electrically insulating spacers or insulators ( 15 ). The reference number ( 16 ) denotes a connection area and the reference number ( 17 ) an outwardly folded and insulated connection end.

Fig. 6 shows a partial winding ( 18 ) in an angular profile with chamfered inner corners ( 18 a) and enlarged outer surfaces, which are obtained by bending from a sheet metal cut. ( 19 ) denotes connection areas for a screw connection, not shown. With similar geometry, massive partial windings ( 18 ) z. B. cast, pressed or deep drawn.

Fig. 7a shows a partial winding (20) of wire, which is cast with an Wärmeleitharz into a compact, dimensionally stable element. With ( 21 ) a connection profile is designated. FIG. 7b shows a sectional view along a line AA in FIG. 7a. Instead of stranded wire, such a partial winding ( 20 ) can also be produced from individual sheet metal strips by gluing, the sheet metal strips being rubbed, ie twisted, so that outer sheet metal strips come cyclically inwards and inner ones outwards. A small current displacement is thus achieved.

Fig. 8 shows a Toroidal inductor (1) having a plurality of in each case by insulating films or insulating layers (23) winding segments or partial windings (22) separate, the circularly arranged around the central recess (6) and in their geometry better seen in Fig. 10 are. The segment pitch angle is again designated with β. At the beginning and end of the total winding composed of 360 ° / β ° partial windings, two separately designed power connection elements ( 30 ) and ( 31 ) are attached, which can be seen better in FIG. 9.

The hatched power connection element ( 30 ), which is led out upwards, forms a segment together with the power connection element ( 31 ), which is shown in dotted lines and is carried out horizontally, but which, unlike the other segments ( 22 ), has no outer web ( 40 ). Due to the interlacing of the segment ( 22 ), the two power connection elements ( 30 , 31 ) are arranged one above the other and, like the other segments ( 22 ), are electrically insulated from one another by an insulating film ( 23 ) that can be seen better in FIG . The insulating film ( 23 ) is slotted in the outer area as seen in the radial direction, so that there it has an upper and lower insulating film section ( 23 a, 23 b), which sections in FIG. 8 are only in the area of the power connection elements ( 30 , 31 ) are shown in solid lines or dotted lines. The power connector ( 30 ) forms z. B. the beginning of the overall winding and the power connector ( 31 ), the z. B. could also be led out horizontally, the end.

FIG. 9 shows the toroidal choke ( 1 ) according to FIG. 8 in a vertical cross section through its center and additionally a central clamping bolt ( 28 ) in the recess ( 6 ), upper and lower insulating plates ( 25 ), an upper disk-shaped clamping plate ( 26 ) , a lower disc-shaped clamping plate ( 27 ) and an electrically insulated pressure bandage ( 29 ) around the central part of the torus, ie around an outer edge ( 41 ) of the partial windings ( 22 ). The high-strength tensioning structure made of steel or of a glass fiber material is designed so that it can absorb the majority of the expansion forces of the winding that occur during a surge current load. (In the case of partial windings from a simple sheet metal cut, the insulating plates ( 25 ) would be provided with radial grooves.)

According to a preferred embodiment of the invention, the central clamping bolt ( 28 ) is connected to disk-shaped clamping plates ( 26 , 27 ) made of steel by thread. The clamping bolt (28) has a central cavity and coolant channel (28 a) in its interior. It is electrically insulated from the partial windings ( 22 ) by insulating rings ( 24 ).

For cooling by a coolant, preferably oil, a coolant inflow channel ( 34 ) and a coolant outflow channel ( 35 ) can be provided in a partial winding ( 2 ). The arrows show the direction of flow of the coolant. Alternatively, a coolant by dash-dotted slit-shaped openings or coolant inflow (32) into the interior of Toroidal inductor (1) and thence through coolant discharge channels (33) and the coolant passage (28) in the interior of the clamping bolt (28) get outside. It goes without saying that the current heat to be dissipated can alternatively or additionally also be dissipated to the surroundings by means of cooling fins (not shown). With ( 39 ) transition points to an adjacent, partial winding ( 22 ) lying behind are identified.

FIG. 10 shows a segment or a partial winding ( 22 ) of the toroidal choke ( 1 ) according to FIG. 8 from a solid winding in a perspective view in detail. The partial winding (22) has a first or initial connection piece (36) and a second or end connector (37) with a lateral, vertical pressure bearing surface (37 ') and a horizontal bearing surface (37' '), which through a recess ( 38 ) are spaced apart. The upper insulating film section ( 23 a) is inserted into this recess ( 38 ) during assembly of the toroidal choke ( 1 ). The remaining part of the insulating film ( 23 ) serves for the electrical insulation of a partial winding ( 22 ) from the neighboring one, cf. FIGS. 8 and 11. In assembling the Toroidal inductor (1) the pressure contact surface of the initial connection piece (36) is a part winding (22) to bear against the pressure face (37 ') of the adjacent winding element. An electrical connection is guaranteed by the contact pressure. Preferably, however, is from the front side by a high-energy weld z. B. generated by means of an electron or laser beam, a weld, not shown, which ensures an even better electrical connection.

It is important that the start and end connecting pieces ( 36 , 37 ) fit to one another or are complementary to one another, so that a flat contact is ensured when adjacent partial windings ( 22 ) are applied. Relatively thick partial windings ( 22 ) can be produced in the desired, spread shape by casting. Flat partial windings ( 22 ) can be made from an annular disk by cutting along a cutting line leading from the inside outwards, for. B. by means of a laser beam and subsequent bending or spreading. Adjacent partial windings ( 22 ) are then soldered or preferably welded along these cutting lines in order to obtain an overall winding.

Fig. 12 shows a detail of a partial winding ( 39 ) with a flat design and enlarged outer surfaces to reduce high-frequency losses. An arrow (B) points in the direction of the connection point, not shown.

With sheet metal cuts, the connecting elements can be soft-soldered, hard-soldered or welded. Press and screw connections are suitable for solid partial windings. The partial windings ( 2 ) are inserted one after the other radially into a winding body, not shown, and the contact points z. B. fixed with screws.

Claims (11)

1. Toroidal choke ( 1 )

• a) with at least 2 power connection elements ( 30 , 31 ) and
• b) several turns,
• c) which are arranged side by side to form a torus,

characterized,

• d) that the toroidal choke ( 1 ) consists of several partial winding segments or segmented partial windings ( 2 , 7 - 10, 13, 18, 22, 39 ),
• e) that each partial winding has at least one turn has and
• f) that each partial winding with at least one connecting element ( 3 ; 36 , 37 ) for series and / or parallel connection of the partial windings is in an electrically conductive connection.

2. Toroidal choke according to claim 1, characterized in that

• a) that the width (a) of legs ( 2 a, 2 b) of the partial windings ( 2 ) in the central, inner region ( 4 ) of the torus is smaller than the width (b) at the peripheral outer edge ( 5 ),
• b) in particular that the height (c) of legs ( 2 a, 2 b) in the central, inner region ( 4 ) is greater than the height (d) at the peripheral outer edge ( 5 ) of the torus ( Fig. 1).

3. Toroidal choke according to claim 1 or 2, characterized in that adjacent legs of partial windings ( 7 - 10 ) have different lengths, measured from the central, inner region ( 4 ) to the peripheral outer edge ( 5 ; 11 , 12 ) of the torus ( Fig. 2). 4. Toroidal choke according to one of claims 1 to 3, characterized in

• a) that the peripheral torus is angular,
• b) in particular rectangular ( 11, 12 ) is limited ( Fig. 3).

5. Toroidal choke according to one of claims 1 to 4, characterized in

• a) that the partial winding ( 18 ) has a box profile with rounded or beveled inner corners ( 18 a),
• b) in particular that the outer surfaces of the partial windings ( 18 ) are enlarged relative to their inner surfaces ( Fig. 6).

6. Toroidal choke according to one of claims 1 to 4, characterized in that

• a) that the partial windings (13) 2 connection elements (13 a, 13 b) which each has an inner angle (α) in the range of 90 ° -150 °,
• b) Include in particular in the range of 100 ° -130 ° ( Fig. 4).

7. Toroidal choke according to one of claims 1 to 6, characterized in that

• a) that the partial windings ( 20 ) are formed from stranded wire,
• b) in particular that the partial windings are made from bolted or twisted sheet metal sections ( FIG. 7).

8. Toroidal choke according to one of claims 1 to 7, characterized in

• a) that the partial windings ( 22 ) have inner and / or outer cooling elements or cooling devices ( 32-35 ),
• b) in particular that a clamping bolt ( 28 ) with an inner coolant channel ( 28 a) is provided in the center of the toroidal throttle ( 1 ) ( FIG. 9).

9. Toroidal choke according to one of claims 1 to 8, characterized in that the partial windings ( 14 ) have a plurality of superposed turns ( Fig. 5). 10. Toroidal choke according to one of claims 1 to 8, characterized in

• a) that at least one partial winding ( 22 ) is a winding segment with one turn
• b) and has a first or initial connecting piece ( 36 ) with at least one first contact point and a spaced-apart second or end connecting piece ( 37 ) with at least one second contact point ( 37 ', 37 ''),
• c) which connecting pieces are mutually intertwined,
• d) in particular that the initial connector ( 36 ) has a fit in the form of a recess or a projection which is complementary to a fit ( 37 ') of the end connector ( 37 ), and
• e) that the start and end connectors ( 36 , 37 ) of adjacent partial windings ( 22 ) are connected by means of a weld seam.