Air core duplex reactor

Abstract

An air core duplex reactor consisting of one, two or more sets of two rigid cylindrical coil assemblies disposed in concentric, radially spaced relation. All of the coils are electrically connected in parallel at one end and have individual connections for the respective sets of coils at the opposite end, one set of coils being interleaved with the other and each coil consisting of a rigid, longitudinally extending sleeve member having a coil wound on a portion of the length thereof extending from adjacent the parallel connected end in a direction toward the opposite end. The sleeve extends beyond the end of the coil to the individual connections, thereby providing insulation against arcing. Each coil member is relatively thin and spaced closely adjacent one another providing a coupling factor of up to at least 85 percent. The rigid coil is provided by a resinous material and, preferably, is glass reinforced. Barrier insulation may be provided in one or more of the coils and such barrier insulation extends from adjacent the individual connections for the coils in a direction toward the opposite end overlapping a portion of the coil associated therewith.

Description

The present invention relates to duplex reactors and, more particularly, to improvements in construction of the same and also improvements incorporating interleaving coils to obtain a high degree of coupling.

Duplex reactors are well known and as examples of the same attention is directed to Canadian Pat. Nos. 602,753 and 614,443 issued, respectively, Aug. 2, 1960 and Feb. 14, 1961 to Canadian General Electric Company Limited.

A principal object of the present invention is to provide improvements to air core duplex reactors and particularly, improvements in the construction whereby a substantially higher coupling factor is attained than in the prior art devices.

Accordingly, there is provided in accordance with the present invention an air core duplex reactor comprising two or more rigid cylindrical coil assemblies disposed in concentric, radially spaced relation, said coils being electrically connected in parallel at one end and having individual connections for the respective coils or pairs of coils at the opposite end, each said rigid coil assembly comprising a rigid longitudinally extending sleeve-like member with a coil wound along only a portion of the length thereof, said coil extending from a position adjacent the parallel connected end toward the opposite end. In a more restricted embodiment, barrier insulation is located between selected ones of the radially spaced coils, said barrier insulation extending at least partially over the length of the coil associated therewith and therebeyond toward the opposite end of the rigid coil assembly terminating at a position adjacent such opposite end.

In accordance with a further aspect of the present invention, there is provided an air core duplex reactor comprising two or more sets of two rigid coil assemblies, all of said coil assemblies being disposed in concentric radially spaced apart relation and electrically connected in parallel at one end, the opposite ends of each set of coils being connected in parallel and having individual connections for the respective sets of coils, each said rigid coil assembly comprising a rigid, longitudinally extending sleeve-like member with a coil extending axially along only a portion of the length thereof, each said coil of the respective coil assemblies extending from a position adjacent the parallel connected end in a direction toward the opposite end and terminating at a position spaced therefrom.

The invention is illustrated by way of example in the accompanying drawings wherein:

FIG. 1 is an oblique broken view of one form of duplex reactor provided in accordance with the present invention;

FIG. 2 is a vertical cross-section along a diameter of the duplex reactor shown in FIG. 1;

FIG. 3 is similar to FIG. 2 but illustrating a modified assembly incorporating a plurality of coils disposed in interleaved relation; and

FIG. 4 is a top plan view of an embodiment similar to that illustrated in FIG. 3.

Referring now in detail to the drawings, shown in FIG. 1 is an air core duplex reactor 10 consisting of rigid cylindrical coil assemblies 20 and 30 disposed in concentric radially spaced apart relation. The coil assemblies 20 and 30 rest upon a rigid spider assembly 40 supported upon insulators 50. The spider 40 is made of a conductive material and has a plurality of arms 41 radiating outwardly from a common axis coextensive with the longitudinal axis of the cylindrical concentrically disposed coils. The insulating support foot members 50 may be of any well known type and secured in any convenient manner to the spider. The coils of coil assemblies 20 and 30 are each electrically connected to the spider 40, thereby connecting the coils in parallel at the lower end as viewed in FIG. 1. The opposite ends of the respective coils are provided with individual terminals, the coil of coil assembly 30 being connected to terminal 60 and the coil of coil assembly 20 being connected to terminal 70. Terminals 60 and 70 are metallic rigid bar members and radiate outwardly in respectively opposite directions from the axis of the coils.

In the embodiment illustrated in FIG. 1, coil assemblies 20 and 30 are independent rigid cylindrical members and are held in assembled relation by a pair of ties 80 and 81. Tie 80 passes over bar member 60 fitting into a notch in the upper edge to hold the same in position and the tie at the opposite end passes around an arm 41 of the spider 40. Similarly, tie 81 passes over terminal bar member 70 and is located in a notch in the upper edge of the same, with the opposite end of the tie being secured to a further spider arm 41.

The coil of coil assembly 20 consists of one or more conductors 21 helically wound around the axis of the cylinder and embedded in a resinous material 22 which may be reinfored with a filler. Preferably the resinous material is reinforced with filament wound glass to provide a rigid assembly when cured. The conductor 21 has a lower terminal end 23 connected electrically to the spider 40 and the opposite end terminates in a lead 24 connected to the terminal 70. The conductor 21 extends axially along the cylinder from a position adjacent the spider 40 to a position spaced inwardly from the opposite end of the cylinder and which is designated generally by the reference numeral 25. The extension of the cylinder beyond the position 25 to the terminals 60 and 70 provides insulation against arcing over between the coil ends. The length of such extending portion, that is the distance between the end 25 of the coil and the terminals 60 and 70, depends upon impulse strength required and may be suitably selected dependent upon the rating of the reactor.

The coil of coil assembly 30 similarly consists of a conductor 31 helically wound around the axis of the cylinder and embedded in a resinous material 32 which again is preferably reinforced with a filler such as, for example, and preferably filament glass. The conductor 31 terminates at the lower end in a lead 33 connected to the spider 40, thereby connecting coils 20 and 30 at such end electrically in parallel. The opposite end of the coil terminates in a lead 36 connected to the terminal bar 60. The wound coil provided by conductor 31 again extends from the end of the cylinder adjacent the spider 40 to a position spaced inwardly from the opposite end terminating at a position generally indicated by the reference numeral 35 corresponding to the position 25 of the coil of coil assembly 20.

Coil assembly 30 is provided preferably, although not necessarily, with barrier insulation 90 which extends from adjacent the terminals 60 and 70 for the coils toward the opposite end overlapping a portion of the coil. The barrier insulation may be any insulative material and preferably a film insulative material such as one, for example, identified by the Trade Mark "Mylar" sandwiched between the outer surfaces of the rigid cylindrical member.

The coil assemblies 20 and 30 are relatively large in diameter, typically being 40-50 inches, and spaced apart radially one from the other by approximately 1/2 inch thereby providing coils closely adjacent one another with a resultant high coupling factor. The coil assemblies typically may have a wall thickness of approximately 1/2 inch and the 1/2 inch spacing between adjacent coil assemblies provides a vertical cooling duct.

In the embodiment illustrated in FIG. 2, there is one set of coils consisting of respective rigid coil assemblies 20 and 30.

In FIG. 3 is illustrated a further embodiment consisting of two sets of coil assemblies 20 and 30 disposed in concentric, radially spaced relation. The coils of coil assemblies 20 and 30 are connected to spider 40 at the lower end thereby electrically connecting the coils in parallel and at the opposite end the coils of coil assemblies 20 are connected to terminal 70, while the coils of coil assemblies 30 are connected to terminal 60. The coils of the pair of coil assemblies 20 are thereby connected in parallel and the coils of coil assemblies 30 are connected in parallel. Further sets of coils may be provided as required depending upon the rating of the reactor. Splitting of the coils, that is providing two coil assemblies 20 and two coil assemblies 30, permits having a high capacity reactor without sacrificing to any great extent the coupling factor by virtue of having all of the coil assemblies relatively thin and closely adjacent to one another. The coils in the FIG. 3 arrangement may be termed as being interleaved, i.e. they alternate radially outwardly first coil 30, then coil 20, and then a coil 30 and coil 20, and so on dependent upon the number of sets of coils that are provided.

In each of the foregoing embodiments, the individual rigid coil assemblies are preformed and subsequently placed in concentric relation. An alternative arrangement is illustrated in FIG. 4 wherein the coil assemblies are formed progressively outwardly, starting first with the innermost coil assembly 30 which may be wound on a rigid cylinder, either removed subsequently or left in place, as a support for the innermost coil. The coil assembly 30 may be formed by winding a conductor onto the cylinder and simultaneously winding therewith the filament glass and resinous material. After coil assembly 30 has been completely formed, spacer bars 100 are placed on the outer surface. the spacer bars extend longitudinally along the formed coil assembly at positions spaced circumferentially from one another. Coil assembly 20 is then formed by a similar winding operation, winding being onto spacer bars 100 which separate one coil assembly from the other. After completing the winding of coil assembly 20, further spacer bars are placed on the outer surface thereof and the next outermost coil assembly 30 is similarly wound therearound. After completion of the winding operation of all of the coil assemblies 20 and 30, the complete assembly is subjected to curing thereby providing a rigid unitary structure comprising as many pairs of coil assemblies 20 and 30 as desired. The assembled coils are supported at one end by a spider 40 and which is tied by members 80 and 81 to the respective individual terminals 60 and 70 at the opposite end of the coil assembly.

In the foregoing embodiments the barrier insulation 90 is illustrated embedded in the coils 30. Additionally or alternatively thereto, barrier insulation may be provided in coil assemblies 20. Furthermore, the barrier insulation may be a single film or, alternatively, two or more films overlapping to provide maximum thickness adjacent the respective terminal ends 25 and 35 of the coils. In utilizing several layers of film, they may be stepped inwardly providing maximum insulation at positions wherein there is the greatest likelihood of arcing from one coil to the other.

In the embodiment described with reference to FIG. 3, the coils of adjacent coil assemblies are connected to respective ones of terminals 60 and 70. Alternatively, the coils of one set of adjacent coil assemblies may be connected to one of terminals 60 and 70 and the coils of the next adjacent pair of coil assemblies may be connected to the other one of the terminals 60 and 70. In such event the barrier insulation, if used, may be located between the adjacent pairs of coils connected to respective ones of the terminals 60 and 70.

Claims

I claim:

1. An air core duplex reactor comprising two or more cylindrical coil assemblies disposed in concentric, radially spaced relation with an air space therebetween, each said coil assembly comprising one or more conductors helically wound and embedded in a resinous material providing a rigid, longitudinally extending sleeve-like member having a coil winding therein, said coil winding being helically wound from adjacent one end of said sleeve-like member in a direction toward the opposite end and extending only along a portion of the axial length thereof whereby the sleeve at such other end projects beyond the helical winding a substantially greater distance than at said one end, film insulation embedded in said projecting portion of the sleeve and overlapping a portion of the helical winding, means at said one end electrically connecting all of said coils in parallel and terminal means at said opposite end of the sleeve assemblies and connected to respective ones of the coil windings providing individual connections therefor.

2. An air core duplex reactor as defined in claim 1 wherein said resinous material member is glass reinforced.

3. An air core duplex reactor as defined in claim 1 including a rigid spider member supporting said coil assemblies at said one end thereof and which provides said means connecting the coil windings in parallel.

4. An air core duplex reactor comprising two or more sets of two rigid cylindrical coil assemblies, all of said coil assemblies being disposed in concentric, radially spaced relation with a space therebetween and electrically connected in parallel at one end, the opposite ends of each set of coils being connected in parallel and having individual connections for the respective sets of coils, each said rigid coil assembly comprising one or more conductors wound helically and embedded in a resinous material providing a rigid, longitudinally extending sleeve-like member, said coil windings extending axially along only a portion of the length of the respective sleeve-like members and arranged such that the windings extend from closely adjacent the parallel connected ends in a direction toward the opposite end of the sleeve-like assemblies terminating at a position spaced from said opposite end a substantially greater distance than the spacing of said coil windings from the parallel connections and film insulation embedded in the portion of the sleeve projecting beyond the winding and overlapping at least an end portion of the winding.

5. An air core duplex reactor as defined in claim 1 including spacers disposed in circumferential spaced relation between adjacent coil assemblies retaining the same in selected spaced relationship.

6. An air core duplex reactor as defined in claim 4 wherein each set of coil assemblies comprises alternate ones of the concentrically arranged coils.