DE19810566A1 - Electrodynamic machine, namely synchronous generator and/or motor - Google Patents

Abstract

An electrodynamic machine, namely a synchronous generator and/or motor has rotor and stator windings of arbitrary polepair number aligned together, located on the machine axis. The rotors have electrically and mechanically connected rotating field windings which generate rotating fields rotating in opposite directions. With motor operation of the machine, the stator windings are subjected to alternating voltage of variable frequency and depending on the difference frequency, a free torque arises at the connected rotors. With generator operation of the machine, an external torque in the direction of rotation engages the connected rotors or the machine axle, which in the non-independently excited part of the stator winding, generates a voltage that can be tapped off with a frequency that depends on the rotor speed, excitation frequency and the pole pair number of the stator and excitation windings. The rotor and stator windings are arranged radially over one another, taking the machine axis as a starting point, or coaxially so that magnetic fields directed radially result.

Description

The invention relates to an electrodynamic machine, namely Synchronous generator and / or motor with one another aligned Rotor and stator windings of any number of pole pairs, which are arranged on the machine axis, the electrically and mechanically connected rotor three-phase windings have which in opposite directions with respect to the runner generate rotating fields.

From European patent application EP 0 311 717 A1 is a Synchronous generator known, which two spaced stators having. The stators enclose two on one axis stands arranged runners that have electrical windings sen.

The windings of the runners are cross-electric trisch connected. The stator windings are connected in parallel and are charged with a constant frequency.

When operating the known synchronous generator with constant Frequency or respectively the same field frequency in the windings or stators, however, leads to unsatisfactory work wise with extremely poor efficiency. Ultimately ent are disturbing harmonics that are necessary for the application of Syn chrongenerators are also disadvantageous.

A proposed frequency-side separation when applied the stator windings with AC voltage only serve the  Adjustment by mutually twisting the windings Stators in the event of an undesirable phase shift.

Based on the briefly outlined known prior art With the patent application 197 31 930.0, such an elec trodynamic machine trained so that this both as Synchronous generator and / or motor or turned on as an alternator can be set, being an inexpensive mechanical and electrical construction is specified, which is beyond guarantee high efficiency under all operating modes continuous

The basic idea of the above-mentioned application is now assume a machine that is aligned with each other Has rotor and stator winding pairs, the along a ge common machine axis are arranged. The runners point electrically and mechanically connected three-phase windings, by a rotating connection reversing conductive connection or ent speaking wiring are able to rotate in opposite directions Generate fields.

According to the invention, when the engine is operating the machine Excitation of the stator windings of the winding pairs with each an alternating voltage of different frequency, where depending on the difference frequency free, tapped torque on the connected rotors or the rotor axis.

When the machine is operated as a generator, an external one acts Torque in the direction of rotation on the connected rotors or the Machine rotor axis, which is in a not externally excited part the stator has a voltage that can be tapped at a frequency testifies, which results from the rotor speed, the excitation frequency of the exciting stator and the respective number of pole pairs results.

In a preferred embodiment of the invention Possibility of combined operation as a synchronous generator and motor of the electrical machine such that, for. B. a  Internal combustion engine is started by the machine about variable frequencies applied to the stator windings be, by the induced voltages and currents in the Runner rotated. The moment the Internal combustion engine can reach its operating speed above the mechanical connection between the driven side of the Internal combustion engine and the machine axis a torque the runners act, then using the machine as a generator acts and feeds into the grid, respectively electrical energy generated. By increasing or decreasing the variable frequencies can, assuming constant engine torque, but what no condition is a change in generator speed and power regulation can thereby be achieved.

According to a further basic idea, the stand can be a he Most of the winding pairs are supplied with a DC voltage become. On the connected runners or the machine or In this case, rotor axis acts on an external torque such that on the stator of a second one of the pairs of windings sets an induced AC voltage so that the Function of an alternator results.

By temporarily shorting the windings of a stator the machine can be started in asynchronous mode be forced. Otherwise for the operation of a synchronous necessary mechanical action of a minimum speed or a minimum torque on the machine axis can therefore omitted.

The runners arranged on the common machine axis be stand in a preferred embodiment from each At least three ladders that form a cage runner.

The rod conductors are short-circuited at the outside end and connected at the mutually facing ends reversing the rotating field.

The rod conductors of the rotor of a first are preferably the Winding pairs in a connecting section essentially parallel in the cage of the ladder of the runner of a second  of the winding pairs extending and there the art angularly shifted against each other in the direction of rotation that corresponding rod ends with simultaneous electrical Isolation of non-corresponding sections using simple Bridges or the like can be connected. To operate of the electrical machine as a motor Stator windings both with constant and variable Frequency as well as with two each variable Frequencies are operated, the essential to the invention The principle is that for the receipt of a corresponding Torque or setting a desired speed Different field frequencies are required.

The stator windings are always different from one another Field frequencies with the same number of pole pairs and with different mechanical speed also generated differently Frequencies.

To achieve a constant output frequency in generator mode hold, with a variable rotor frequency the stator Excitation field changed accordingly or at constant Excitation frequency results in a Ver with the rotor speed Change in frequency in the second stator winding. Engine- and generator functions of the electrodynamic machine NEN are characterized in that in both cases on the respective Stator windings to ver different magnetic field frequencies are drawing and the runner depending on the right resulting differential frequency rotates.

In the alternator operating case, as explained, the Apply a DC voltage to windings of a stator part strikes. This induces in the windings of the corresponding Runner part with mechanical rotation a resultant Tension. This creates an in over the other runner part Direction of rotation rotating magnetic field, which in the associated Stator induces an alternating voltage. Through the frequency a correspondingly higher output can be obtained.  

The manufacturing costs of the electrodynamic machine can through the proposed training of cage runners already be significantly reduced, with the rotor parts prefabricated Cast or molded parts can be mechanical and are electrically connected. The number of rod ladders in each the squirrel cage must be ≧ 3. With an increase in the number of the rods, the waveform of the induced Change the frequency in the direction of the sinusoid.

The present invention is based on the object Synchronous generator of the type described above continue to do so form that the design in the sense of a space reduction, ins special reduction in length, can be changed, and the electrical necessary for reversing the rotating field Connection between the rotor parts should be simplified.

The object of the invention is achieved with a Subject according to the features of claims 1 or 5, the subclaims being at least useful configurations and training.

According to the first embodiment of the invention is of radial aligned, rotating magnetic fields The stator and rotor windings or cages of the machine axis starting radially one above the other or coaxially are arranged so that the resulting magnetic fields against can rotate sensibly.

In this embodiment, two magnetic fields rotate accordingly at different radial distances from the shaft between Stands and runners in opposite directions. The areas covered by these Form fields between runner and stand are covered Cylinder, the cylinder with the smaller diameter in other cylinder is arranged quasi coaxially. The desired opposite rotation is due to the electrical interconnection the rotor windings or the bars of a squirrel cage reached. The rotor bars can preferably at different number of poles of the inner and outer part are connected in parallel, so that for example a rod  is connected inside with two rods outside. As a winding support or winding bodies can be used, which are made of the manufacture of electrical machines are generally known.

In a further development of the first embodiment, this consists from a three-cylinder arrangement with an inner cylinder stand and an outer cylindrical stand, wherein between these two cylinders be the cylindrical rotor is sensitive. The inner and outer rotor winding of the zylin Dried runners are connected in opposite directions to the ge wanted to ensure magnetic field rotation.

The arrangement of the windings one above the other reduces the installation space compared to this embodiment of the invention the known prior art. The size of the stand is due to the different diameters of the windings Cylinder arrangement also different. Preferably on the stator winding closest to the machine axis below Consideration of the heat dissipation as excitation winding designed according to lower performance.

When running as a squirrel cage, the electri connection for reversing the rotating field at one axial end and the short circuit connection at the opposite end part of the Runner. This makes this connection very easy leads, for example on U-shaped rods can be used, the ends of which are short-circuited and their arches cross each other. Here is the advantageous one Possibility to manufacture the rods by injection molding.

The overall construction described above is extremely simple and compact. In one embodiment as a generator with a is the construction volume in the Compared to performance lower than in the prior art because at the same speed, the excitation frequency of the rotated Rotor field with the same number of poles compared to the corresponding stator winding doubled.  

The runner plates can be used twice, but just if there is a possibility of separating the inner from the external magnetic flux through the use of an appropriate Intermediate layer or a differentiated sheet arrangement too full pull.

In the second embodiment of the invention, the Stator and rotor windings axially on the machine axis arranged adjacent, each between two stator windings because there is a runner. The opposite rotation of the Fields is created by interconnecting the inner and outer Ren windings realized, in one embodiment with several runners arranged on a common axis become.

The second embodiment is also simpler Possible way, using a rod or cage runner Short-circuit the rods radially at one end and at the opposite Connect the overlying end so that a rotating Magnetic field on one side of the rotor rotating in opposite directions of the field on the other side of the runner.

The stator and rotor windings or cage rotors are accordingly So axially arranged on the shaft, between the stator and Runner at least two axially adjacent magnetic fields with axial alignment of any number of poles in opposite directions ren.

The areas that these fields between runner and Covering the stator winding forms quasi disks. The ge Sensitive rotation is achieved through the electrical connection of the Rotor windings or rods reached as described above.

When using rotor bars of a squirrel cage, this is done electrical connection to reverse direction of rotation preferably on outer radius and the short circuit of the rods preferably inside. The rotor and stator plates are aligned axially.  

The respective ones are advantageously wound Sheet metal packages and a subsequent insertion of slots to hold the bars or windings.

Because with a simple execution of the electrodynamic Axial forces on the machine axis or shaft work in a further training on the machine axis two runners, each between stator windings the, arranged.

The constructive arrangement is preferably such that a symmetrical structure on both sides of the transverse axis of the medium stator windings is realized. Preferably who the middle stator windings in the training as Excitation windings executed. In the axial direction to the outside the rotor disks are then arranged, which in turn faces outwards The corresponding load windings are directed opposite hen.

The second embodiment of the invention now leads to the fact that the winding heads of the rotor and stand are close together lie so that the desired space reduction can be achieved is. The overall structure is extremely simple and compact, being the second embodiment in a particularly advantageous manner for Slow speed, e.g. B. wind power generators is suitable.

The electrical connections in one embodiment as Squirrel-cage rotors are real like the first embodiment siert.

With regard to the design of the electrical connection to Phase reversal applies according to the invention that with a machine not a complete change of direction of rotation for several pole pairs necessary is. Here it was recognized that it was for a function is sufficient if the direction of rotation is in one Angular range of 360 ° / number of poles is changed.

In the above-mentioned embodiments, by Crossing the bars relatively easily the connection between the individual rotor parts are produced, with the  Electrical insulation is provided at the intersection. Rods that are at the same angle to the magnetic poles be connected in parallel, reducing the number of crossings is reducible.

With a large number of rods per magnetic pole, the conductive one Connection preferably disc-shaped with the same Alignment and in a similar form to the ferromagnetic Sheets of the runner parts executed. These conductive disks are isolated from each other. The rods are attached to the desired one soldered th place to the ferromagnetic sheets, whereby for adequate insulation from the panes of others Potentials care must be taken.

The invention will now be described with reference to the description of Embodiments and with the help of figures are explained in more detail.

Here shows:

Fig 1a shows a longitudinal section through an electro-dynamic machine according to the first embodiment in an axial arrangement ko.

FIG. 1b a cross section through the electrodynamic machine along the line according to Fig. 1a;

FIG. 2a shows a longitudinal section through the electro-dynamic machine according to the second embodiment;

FIG. 2b shows a cross section along the line according to the Fig. 2a;

Fig. 2c shows a longitudinal section through an electrodynamic machine, which is free of axially directed force components;

FIG. 3a shows a schematic illustration of the electrical interconnection of the electro-dynamic machine accelerator as the first embodiment;

Figure 3b is a principle illustration of the construction of the rotor cages in an electrodynamic machine with radially aligned, one above the other counter-rotating magnetic fields.

FIG. 4a shows a basic electrical interconnection of the windings of an electrodynamic machine accelerator as the second embodiment;

Figure 4b is a representation of the structure of the rotor cages an electrodynamic machine with axially from directed opposite to each other in power Rotie magnetic fields.

Figs. 5 and 6 are illustrations for realizing the Drehfeldum traffic;

Fig. 7 diagrams for connection of the armature coils at a low number of rod per pole; and

Fig. 8 is an illustration of the execution of the connections with a high number of rods per pole.

First of all, it should be noted that those shown in the figures Issues should be considered as essential to the invention.

FIGS. 1a and 1b show a longitudinal and a cross section through an electro-dynamic machine according to the embodiment of the invention, it most.

In this embodiment, a three-cylinder arrangement is assumed. An inner stator 7 , comprising an inner laminated core and at least one inner stator winding 8, is firmly connected to an outer stator, comprising outer stator windings 6 and an outer laminated core 5 . The cylindrical laminated core 1 of the rotor is connected via structural elements to a correspondingly mounted machine axis and is rotatable. The bars of the rotor, ie in the inner and outer cages are provided with the reference number 2 . The direction of rotation reversal 3 is achieved by crossing the rods at a corresponding end. There is a short-circuit ring 4 at the opposite end.

An optional separation of the rotor plates is designated by 9 in FIG. 1b.

In the embodiment shown in FIGS. 1a and 1b, the rotor and stator windings, starting from the machine axis, are arranged radially one above the other or coaxially in such a way that the resulting magnetic fields can rotate in opposite directions.

The rotor sheets themselves lie one above the other in a cylindrical shape the bars of the inner and outer field are on one Side of the cylinder short-circuited in a ring. On the opposite side then finds the necessary one Phase reversal instead. The cylinder can be used for machines lower performance, e.g. B. including by injection molding the areas to be short-circuited and the phase reversal easily produce. For the required insulation of the bars, a Ring made of a heat-resistant insulating material with suitable recesses are enclosed with the laminated core and the runner sprayed out in one operation. The finished rotor cylinder is preferably by a disc on the side of the Short-circuit rings connected to the machine axis. Internally of the rotor cylinder sits mechanically with the housing connected excitation coil with DC or three-phase winding. The outside of the rotor cylinder is fixed to the stand connected work winding arranged in the by the rotating rotor rotating field current is induced.  

With an electrodynamic machine as above, the production is simplified, resulting in a compact design and overall lower costs. The embodiment of the electrodynamic machine according to FIGS. 2a and 2b relate to an arrangement of stator and rotor windings on the machine axis axially adjacent.

A first laminated core 1 of a first stator winding lies at a distance from a laminated core 2 of a second stator winding. The laminated core 5 of the rotor is located in the space between the first and the second laminated core 1 , 2 . This laminated core or the rotor is connected to the machine axis and rotatable. A first stator winding 3 be found on the first laminated core 1 and a second stator winding 4 on the second laminated core 2 . The reference number 6 denotes connections for reversing the rotating field and the reference number 7 short-circuit rings. Rotor windings or rods of a cage rotor 8 are further components of the rotor rotating around or with the machine axis.

As can be seen from the pictures, stand and Rotor windings or correspondingly cage rotor axially on the Shaft arranged, at least between the stator and rotor two axially adjacent magnetic fields with axial Rotate the orientation of any number of poles in opposite directions. The Areas that cover these fields between runners and stands paint, form slices. The required opposite Rotation is by means of an appropriate electrical circuit of the rotor windings or rods.

Since the embodiments shown in FIGS. 2a and 2b also have undesirable axial forces per se, there is the possibility of a symmetrical design of the electrodynamic machine according to FIG. 2c. In this embodiment, two rotors are arranged on the machine axis, each of which is surrounded by stator windings axially spaced apart. The inner stator windings are preferably used as exciters, the outer stator windings being load windings.

For the electrical connection of the machines according to the first and second embodiments, reference is made to FIGS . 3a and 4a.

With regard to the structure of the rotor cages with radially aligned, mutually oppositely rotating magnetic fields, there is the possibility, as shown in Fig. 3b, to connect rotor bars on one side electrically crosswise and on the opposite side a simple short circuit of the inner ring on the one hand and the outer ring or To reach the cage on the other hand.

The electrical connection for reversing the rotating field can also be carried out just as simply in rotor cages which generate axially aligned magnetic fields which rotate in opposite directions to one another. The rotor bars according to FIG. 4b are interconnected by circular or rectilinear parts for reversing the rotating field, a short circuit of the cage parts being achievable on the inside by washers or rings.

In general, it can be stated that machines with ent opposing rotating magnetic fields reversing the electri the rotating field between the rotor parts rig is to be implemented. The design of this phase reversal has however decisive influence on the manufacturing effort.

In the case of electrical machines with several pole pairs, however, no complete change in the direction of rotation has to be carried out. It is sufficient here if the direction of rotation is rotated in an angular range of 360 ° / number of poles. As shown in Fig. 7 Darge, can be made relatively easy by crossing the bars an electrical connection between the rotor parts. Electrical insulation is provided at the crossing point.

Rods that are at the same angle to the magnetic poles be connected here in parallel, which increases the number of Intersections reduced.

With a larger number of rods per pole, the conductive one Connection preferably disc-shaped with the same Alignment and in a similar form to the ferromagnetic Execute sheets of the rotor parts. The conductive disks, e.g. B. copper sheets are correspondingly mutually electrical isolated.

FIGS. 5 and 6 show a possible embodiment of a compound in axially adjacent rotor parts. Here the rods are soldered to the sheet metal at the desired location. The insulation of the sheets from the panes of other potential can be achieved by maintaining a distance, ie by air insulation.

Fig. 8 shows an embodiment of the compounds at high speed rod per pole and axially aligned magnetic fields.

All in all, it succeeds with the electrodynamic machines according to the above-described embodiments Design and space to reduce and by the association fold execution of the runner the effort for the electrical Establish connection for reversing the rotating field between the rotor parts Lich to reduce, so that the manufacturing costs are reduced can.

Claims (6)

1. Electrodynamic machine, namely synchronous generator and / or motor with mutually aligned rotor and stator windings of any number of pole pairs, which are arranged on the machine axis, and the rotors have electrically and mechanically connected rotating field windings, which generate oppositely rotating fields, during motor operation the machine, the stator windings are each subjected to alternating voltage of different frequency and a free torque is set at the connected rotors as a function of the differential frequency; When the machine is operated as a generator, an external torque in the direction of rotation attacks the connected rotors or the machine axis, which generates a voltage that can be tapped in the non-externally excited part of the stator winding at a frequency that is dependent on the rotor speed, the excitation frequency and the number of pole pairs of the stator and excitation winding depends, characterized in that the rotor and stator windings starting from the machine axis are arranged radially one above the other or coaxially such that radially aligned magnetic fields result. 2. Electrodynamic machine according to claim 1, characterized, that this consists of a three-cylinder arrangement with an inner cylindrical stator winding and an outer cylindrical  Stator winding, with a cylindri between them shear runner. 3. Electrodynamic machine according to claim 2, characterized, that an inner and outer rotor winding of the rotor against are sensibly switched. 4. Electrodynamic machine according to one of the preceding Expectations, characterized, that in the case of a rod or cage rotor, the rods on an axia len short-circuited and electrical at the opposite end trisch conductively connected so that an inner rotating Magnetic field is an external, oppositely rotating magnetic field generated. 5. Electrodynamic machine, namely synchronous generator and / or motor with mutually aligned rotor and Stator windings of any number of pole pairs, which on the machine axis are arranged, and the rotor electrically and have mechanically connected rotating field windings, wel che generate fields rotating in opposite directions, whereby at Motor operation of the machine with the stator windings AC voltage of different frequency are applied and a free one depending on the difference frequency Sets torque on the connected rotors; when the machine is operated as a generator, an external torque in Direction of rotation on the connected rotors or the machines axis that attacks in the non-separately excited part of the Stator winding a tapped voltage with a frequency generated by the rotor speed, the excitation frequency and depends on the number of pole pairs of the stator and the field winding, characterized, that the stator and rotor windings on the machine axis are arranged axially adjacent, between two Stator windings each have a rotor, and that rotating the fields in opposite directions by interconnecting each  because inner and outer rotor windings can be realized, with several runners on a common Machine axis are arranged. 6. Electrodynamic machine according to claim 5, characterized, that with a rod or squirrel-cage rotor, the rods on a ra dialed short-circuited end and so at the opposite end are connected that a rotating magnetic field on a Rotator side rotating in opposite directions on the other Causes runner side.