Abb Management Ag

Asea Brown Boveri Inc.

Asea Brown Boveri Ag

Bbc Brown, Boveri & Company, Limited

Hans Zimmermann

Johann Kleinburger

Marius Geller

Lothar Koppetsch

Markus Iseli

Stefan Lanz

Jose-Pierre Paroz

Sandor Pongracz

Ivan Novosel

Jurgen Baer

In the case of thermal power installations in which a gas turbine and a steam turbine jointly drive a turbo generator, the slip rings (8, 9) are arranged on a separate slip ring shaft (14) which is connected to the actual shaft or machine shaft (10) of the electric machine by means of a first detachable coupling (11). The slip ring shaft is provided on its end averted from the electric machine with a coupling flange (15) which is not connected to the slip ring shaft (14) by welding until after the slip rings (8, 9) have been pushed on. The use of an expensive shrink-on coupling between the turbo generator and steam turbine is avoided in this way without increasing the overall length of the turbo generator.

Electric synchronous machine having slip rings arranged outside the

In gas-cooled electrical machine with an axial fan (9) at one shaft end and with a rotor (1) and a stator body surrounded by a machine housing (14), a gas-guide device (18) arranged coaxially to the rotor shaft is provided in the outflow space (17) of the axial fan (9), out of which gas-guide device the cooling gas conveyed by the axial fan is fed to the rotor and to the stator body and stator winding. Said gas-guide device (18) comprises a plurality of guide rings (19-25) in the form of a cone envelope and spaced radially from one another and a ring part (27) likewise in the form of a cone envelope, which rings and ring part are connected to one another and to the machine housing (14) directly, or indirectly by means of bars (28, 29) extending essentially radially and/or guide plates (36, 36'). Ring-shaped channels (K.sub.1, . . . , K.sub.8) widening continuously in the direction of flow of the cooling gas are formed between respective radially adjacent guide rings, and between the ring part (27) and its adjacent guide ring. The gas-guide device (18) brings about a pressure transition, and it reduces the outlet losses downstream of the latter in relation to the hitherto conventional axial outlet provided by the rotor configuration. Between 15% and 25% of the pressure losses in the machine can be saved in this way and consequently the cooling effect can be greatly increased.

Electrical machine with an axial fan

In the case of a gas-cooled electrical machine, the effective flow cross-section of the connection from the outer hot-gas chambers to the cooler is provided with an adjustable restrictor device (29, 31; 32, 33). In this way, the splitting of the various cooling-air flows within the machine can be influenced, without intervention in the actual machine, such that equalization of the temperature level in the machine longitudinal direction is achieved.

Gas-cooled electrical machine

The device for holding the ends of the turns of a stator winding in a dynamoelectric machine comprises an inner ring (15) and a segmented outer ring (10). The stator winding, which consists of bottom and top bars (5, 6), is supported at the end side on the said outer ring (10), which in turn is supported by brackets (8) which are fastened to the machine end face. The bottom and top bars are spaced from one another by pressure hoses (13) filled with synthetic resin. The inner ring (15) consists of two rings having a closed inner conical ring (15b), an outer, preferably multipartite conical ring (15a) and support segments (15c), it being possible for the two conical rings to be braced axially with one another. A winding overhang support constructed in such a way fulfils all practical requirements and can also be reclamped subsequently.

Device for holding the ends of the turns of a stator winding in a

In order to cool a rotating electrical machine having an open cooling circuit, mechanically filtered environmental air is normally passed through the cooling ducts in the stator and rotor and the machine air gap (22) by means of fans (15) which are arranged on both ends of the rotor shaft. If the air which is taken from the environment is contaminated with hazardous materials, it is proposed to supply the prefiltered air directly to the stator and the machine air gap and to subject only the cooling air which is to be supplied to the rotor to refiltering in an activated charcoal filter (30). In this case, the mechanically filtered cooling air which is to be supplied to the stator and possibly the machine air gap is passed through the fans, while the refiltered cooling air which is to be supplied to the rotor is passed into the rotor on a separate route. The cooling air for the rotor is in this case preferably conveyed by the rotor's own ventilation. In this way, the investment costs for the subsequent filters are reduced while only a fraction of the required quantity of air still needs to be refiltered.

Air-cooled rotating electrical machine

The winding overhang support of a turbo-generator comprises an inner ring (12) which fits closely, either directly or with the insertion of an interlayer (14), against the ends of the turns of the stator winding (4, 5), which ends widen like an internal taper, and a multipart external support comprising rings (9, 27) and supporting brackets (7). The supporting brackets (7) are attached to the end of the stator core end plate (3) of the laminated core. The first outer ring (9), which is composed of insulating material, fits closely against the outside of the free ends of the supporting brackets (7). The second outer ring (27) is manufactured from high-strength nonmagnetic steel and is supported on a shoulder (26) on the stator core end plate (3) and is attached to the supporting brackets (7). There are double-wedge clamps (16, 17, 20) between the inward-facing surfaces (18, 19) of the supporting brackets (7) and the ends of the turns. Due to the support of the second outer ring (27) on the shoulder (26) of the stator core end plate (3), it can only expand in itself but cannot deform into an oval shape. This makes the winding overhang support very rigid radially and meets all requirements of practical service, especially in the case of a short circuit.

A rotor of a turbogenerator having direct gas cooling of an excitation winding conductor. An insulating strip is provided between a slot base and the excitation winding conductor. A resiliently elastic intermediate layer, which may be in a form of a corrugated spring, is provided between the insulating strip and the excitation winding conductor in order to compensate for seating phenomena of the excitation winding. This corrugated spring extends in a direction of the rotor body center, originating from the body end. In order to fix this corrugated spring axially without the cross section of the keyway being constricted, the corrugated spring has a pair of projections which point downwards and engage in lateral recesses in the insulating strip.

Rotor of a turbogenerator having direct gas cooling of the excitation

Horizontal-axis electrical machine having a stator laminate core (1) which is arranged in a housing (2, 3) which is split horizontally, which stator laminate core (1) is clamped by means of fastening wedges (35), which are distributed over its circumference, in supporting rings (32), which are arranged orthogonally to the machine longitudinal axis and are spaced apart from one another. The supporting rings are connected on their external circumference, via fastening parts (39, 40), to the housing lower part (2) of the machine. The supporting rings (32) have azimuthal fastening plates which run symmetrically with respect to the vertical plane of symmetry of the machine. In order to decouple the stator laminate core (1) from the housing lower part (2), the fastening plates (40) are fastened to the said supporting rings such that they are sprung horizontally in the radial direction, the fastening plate (40) itself being constructed as a leaf spring, or acting as such.

Horizontal-axis electrical machine

In the arrangement for fastening a machine part on a foundation by using vertical anchor studs, a multiplicity of vertical anchor tubes are cast into the foundation and these are connected to one another, at least in groups, by means of an auxiliary frame. Provided at the lower end of each anchor tube, there is a ring whose inner diameter is greater than the outer diameter of the anchor stud and whose outer diameter is greater than or at least equal to the outer diameter of the anchor tube. A space with an essentially square outline is recessed in the foundation underneath this ring. Laid in this space with clearance, there is a threaded nut with an essentially square external contour and a height smaller than the clear height of the space mentioned, the lower end of the anchor stud being able to be screwed into this threaded nut. This design makes it possible to omit expensive templates when casting the foundation. In addition, the subsequent horizontal alignment of the machine part or machine is possible without difficulty.

Arrangement for fastening a machine part to a foundation

In gas-cooled electric machines having a stator (3) and a rotor (6) on which an axial ventilator (9) is arranged, the cooling gas flows unevenly into the end-winding cavity (13) seen in the circumferential direction. By providing upstream of the axial ventilator (9), when seen in the direction of flow of the cooling gas, and coaxially with said ventilator an annular air guide member (1) having baffles (17), and reducing the flow cross section for the cooling gas flowing through the air guide member (1) in the main direction of the approach flow on a part of the outer circumference of the air guide member (1) by means of a covering (23), the cooling effects becomes more even and the axial ventilator (9) is better utilized.

Gas-cooled electric machine

In the gas-cooled electric machine, the stator winding bars, which are connected to one another electrically and mechanically outside the stator core assembly (2) in the overhang space by means of metallic lugs, are provided with caps (8) which virtually completely surround the lugs while leaving free one or more approximately axially extending ducts (9). These ducts (9) are open towards the stator core assembly (2). At its end on the partition side, the cap (8) has an opening (10) which is freely connected to said ducts (9). A flexible line (11) leads from this opening directly into the suction chamber (14) of the fan (5). As a consequence of the pressure difference between the suction chamber (14) and overhang space (13), some of the coolant conveyed by the fan (5) flows through said ducts and cools the rod ends and lugs (7).

In horizontal-axis electrical machine, a laminated stator core is provided with a stator frame consisting of support rings and axial support bars. The frame is suspended in a housing by means of a bolt arrangement. In this arrangement, the construction is suspended in such a manner that the stator is held in place elastically in the axial direction, and rigidly in the radial and circumferential directions.

Horizontal axis electrical machine with radial support bolts

A stator laminated core (1) of a horizontal-axis electrical machine is supported by means of at least two parallel bearing plates (3), perpendicular to the axis of the electrical machine and at a distance from each other. In order to minimize vibrations and thermal stresses occurring during the operating state of the electrical machine, the bearing plates (3) are of annular design and are connected to the bottom casing section (8) only in two regions of their horizontal plane of symmetry, on either side, via vertical linear extensions (4) by means of attachment parts (5). By far the greatest part of the circumference of the bearing plates (3) is at a distance from the bottom casing section (8) and the top casing section (9). The stator laminated core (1) is braced in the bearing plates (3) by means of attachment wedges (6) evenly distributed around its entire circumference. The attachment parts (5) include attachment plates (15) which are each welded to the extensions (4) of the bearing plates ( 3). Reinforcing, horizontal-axis tube lengths (14) are welded to the attachment plates (15). The attachment according to the invention of the stator laminated core (1) allows easy accessibility of the structural parts to be welded and ensures a good quality of the welds.

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Monchaltorf, Switzerland

Hans Zimmermann