DE102005025944B4 - Wind turbine - Google Patents

Abstract

Wind Turbine with a generator unit (1) driven by a wind turbine (2), a stand (5) and a runner (6), wherein the stand (5) in a housing capsule (4) is arranged and the runner (6) in the housing capsule (4) is stored, the runner (6) with the wind turbine (2) over a drive shaft (7) is connected through the housing capsule (4) passes through, and the housing capsule (4) the stand (5) and the runner (6) encapsulates in a high degree of protection, characterized in that the housing capsule (4) a cold pole and that the generator unit (1) has a dehumidifying device (11) has, from the at the cold pole Air from the housing capsule (4), the extracted air is dehumidified and the dehumidified air of the housing capsule (4) at one from the cold pole is returned to the remote location.

Description

The The present invention relates to a wind turbine with one of a wind turbine driven generator unit comprising a stator and a runner having, wherein the stand in a housing capsule is arranged and the runner in the housing capsule is stored, the runner with the wind turbine over one Drive shaft is connected, which passes through the housing capsule, and the housing capsule the stand and the runner encapsulated in a high degree of protection.

Such wind turbines are well known. Exemplary is on the DE 102 33 947 A1 referred to the applicant.

Especially in offshore locations and in off-shore operation, the generator unit is exposed to moist and salty air. For this reason, special measures must be taken to ensure the reliability of the wind turbine in continuous operation. In the above mentioned DE 102 33 947 A1 For example, a closed primary cooling air circuit is provided, which is cooled by a secondary cooling air circuit. The outside air is thus kept away from the interior of the housing capsule.

The solution of DE 102 33 947 A1 Compared to wind turbines with direct fresh air cooling, this represents a considerable advance. Nevertheless, even this wind turbine can still fail in individual cases.

The The object of the present invention is a wind turbine to create an even higher one reliability in continuous operation.

The Task is solved by that the enclosure capsule a cold pole and that the generator unit is a dehumidifier has, from the at the cold pole Air from WO 2004/029450 A1 is a wind turbine with a driven by a wind turbine generator unit known. The generator unit has a stator and a rotor, the stand in a housing capsule is arranged and the runner in the housing capsule is stored. The runner is over with the wind turbine connected to a drive shaft which passes through the housing capsule. At the housing capsule a control cabinet is arranged, which is encapsulated. The control cabinet capsule has, among other things, a cold pole on which condensation is separated and led to the outside. This cold pole provides in conjunction with a heater and a fan one Dehumidifying device for the Control cabinet dar.

Also from the DE 101 39 556 A1 is known a wind turbine with a wind turbine driven generator unit having a stator and a rotor. The stand is arranged in a housing capsule and the rotor is mounted in the housing capsule. The rotor is connected to the wind turbine via a drive shaft which passes through the housing capsule. In this wind turbine, a dehumidifier is arranged in the tower, is separated from the condensation and out through the tower wall to the outside. is removed from the housing, the extracted air is dehumidified and the dehumidified air of the housing capsule is fed back to a remote location from the cold pole. The dehumidifying device is preferably arranged outside the housing capsule.

Because This ensures that in the housing capsule no condensation can form.

Preferably the dehumidifier is directly outside the housing capsule attached. Because then the wind turbine is more compact.

If inside the housing capsule in areas where condensation could accumulate, collecting and discharge channels are arranged, such condensation is also in the case of a collection derived. The collection and discharge channels should be a slope of at least 2%, preferably at least 5%.

The lead away the condensate from the housing capsule as such can be effected in various ways. For example may be intermittent (e.g., every ten minutes or every hour) for a short time activate a pump, which pumps off condensed water.

Preferably are those inside the enclosure capsule arranged elements of the generator unit without exception rounded off, wherein the rounding a radius of curvature of at least 3 mm, preferably of at least 5 mm. Because then also adheres to the rounding an applied protective lacquer better than sharp edges and kinks.

If within the housing capsule arranged elements with a multi-layer thick-layer protective coating are painted, the corrosion protection is even better. Under one Dickschichtlackierung is a paint to understand that a Thickness of at least 0.3 mm, preferably of at least 0.5 mm.

Preferably, the housing capsule in the passage region of the drive shaft by means of a Sealing sealed, the spring-loaded is pressed against a stop of the housing capsule. Because then the sealing of the housing capsule to the windward side is particularly simple and reliable bewerkstelligbar.

In usually the runner points axially and radially extending cooling channels, the radially outward are open. If in this case the rotor is radially outward of a bandage is surrounded, the bandage preferably in the area the cooling channels recesses on and / or is interrupted there. Because of this, the rotor cooling can be optimized.

The Generator unit is usually designed as a synchronous machine. In such synchronous machines, the stator is via a converter connected to a power grid.

If between the stand and the converter device on the one hand and between the converter device and the power grid on the other hand filter means are arranged, can Harmonics caused by the inverter significantly attenuated or be reduced. In the stand and also in the runner Therefore, only small eddy current losses occur. This is special because of this fact, because the cooling system can be relatively small dimensions.

Especially Due to the presence of the filtering devices, it is possible that between arranged the converter and the power grid no suction throttles are. this leads to an even smaller and cheaper Construction of the wind turbine.

Preferably the converter means a number of parallel to each other switched inverter units, wel che with a phase offset from 360 ° through n be operated electrically. n is the number of each other Parallel connected inverter units. Because by such Operating mode can otherwise occurring bearing currents avoided or at least be significantly reduced. The reliability of the generator unit This can be significantly increased become.

If in the stand an additional current is fed, compared to that induced in the stator Voltage at 90 ° electrical out of phase, the efficiency of the generator unit can be optimized. Furthermore, the inverter can be made smaller.

If at the runner Permanent magnets are arranged, which are axially and tangentially from each other are spaced can Eddy current losses in the rotor be significantly reduced. This improves the efficiency of Generator unit still further. The axial distance of the permanent magnets can be achieved for example by the fact that the permanent magnets at least partially glued together and in the adhesive layer Spacers are inserted between the permanent magnet, for example small glass beads with a diameter of approx. 0.1 mm.

If the permanent magnets on U-shaped Jochen are arranged, which are open to the stand, are the U-shaped Preferably, yokes are spaced tangentially from each other. Because it can the reactance in the transverse axis can be further reduced, which also leads to a reduction in eddy current losses.

The Eddy current losses can be further reduced if the stand has a stator core, the is divided axially.

Further Advantages and details will become apparent from the following description an embodiment in conjunction with the drawings. Here are a schematic diagram:

1 a wind turbine,

2 a detail of the interior of a housing capsule,

3 a side view of 2 .

4 an element rounding,

5 a runner,

6 a block diagram,

7 a pointer diagram,

8th a detail of 5 .

9 a section of 1 and

10 bonded together permanent magnets.

According to 1 a wind turbine has a generator unit 1 on top of that by a pinwheel 2 is driven. Windmill 2 itself is caused by wind 3 set in rotation.

The generator unit 1 has a housing capsule 4 on, among other things, a stand 5 is arranged. The stand 5 interacts with a runner 6 together, in the housing capsule 4 is stored.

The runner 6 is with the windmill 2 via a drive shaft 7 rotatably connected. Alternatively to the direct coupling of the wind turbine 2 with the delusion fer 6 , can be between wind turbine 2 and runners 6 also a transmission be interposed. The drive shaft 7 must therefore through the housing capsule 4 pass through. The housing capsule 4 but should the stand 5 and the runner 6 encapsulate in high degree of protection (IP54 and better). To such encapsulation in the passage region of the drive shaft 7 to be able to guarantee, is the housing capsule 4 in the passage area of the drive shaft 7 by means of a sealing ring 8th sealed. The sealing ring 8th is about springs 9 spring-loaded, allowing it against a stop 10 the housing capsule 4 is pressed.

Due to the encapsulation moisture can not or only to a small extent in the housing capsule 4 penetration. As far as the humidity in the interior of the housing capsule 4 but already exists, this moisture must be dissipated. This is necessary to avoid corrosion damage in continuous operation. To avoid this corrosion damage two groups of measures are planned.

For one, the wind turbine has a dehumidifier 11 on. The dehumidifier 11 is preferably outside of the housing capsule according to the embodiment 4 arranged, for example, outside of the housing capsule 4 attached. It removes - eg via pipelines 12 - Air from the housing capsule 4 , dehumidifies this air and leads the dehumidified air back to the housing capsule 4 to. The point at which the air is removed is the cold pole of the housing capsule 4 that is, its coldest spot. The place where the air of the housing capsule 4 is returned, is removed from this cold pole. This also results in an air flow, which is for the cooling within the housing capsule 4 arranged elements 5 . 6 , in particular of the stand 5 and the runner 6 , is beneficial.

With these measures, condensation is largely avoided. In the event that condensate nevertheless forms (eg in the short term due to a temperature drop or in the longer term due to a failure of the dehumidifier 11 ) are according to 2 inside the housing capsule 4 in areas where condensation could collect, collection and discharge channels 13 arranged. The collection and discharge channels 13 lead any condensed water to collection areas 14 where the condensation water is discharged to the outside. For example, the condensed water can each be pumped off after a predetermined time. The period between two pump-down procedures can be fixed or variable. In order to be able to optimally fulfill their collection and discharge function, the collection and discharge channels should 13 according to 3 have a gradient of at least 2%, preferably at least 5%.

Another measure to prevent any corrosion damage is, according to 4 inside, inside the housing capsule 4 arranged elements 5 . 6 the generator unit 1 without exception round off. The rounding off 15 preferably have a radius of curvature r, which is at least 3 mm. Preferably, it should even be at least 5 mm. Because of such rounding off 15 is achieved that a protective varnish 16 that is on the elements 5 . 6 is applied, the elements 5 . 6 also very tightly covered in the rounding areas.

How out 4 It can also be seen that the protective lacquer exists 16 of several layers 17 and has a total thickness d of at least 0.3 mm, preferably even at least 0.5 mm. It is the protective varnish 16 thus a multi-layer thick-layer protective coating 16 ,

Both the stand 5 as well as the runner 6 should have the lowest possible eddy current losses. Furthermore, resulting heat loss should be easily dissipated. To run in the runner 6 to be able to dissipate the resulting waste heat well, the runner points 6 according to 5 cooling channels 18 on. The cooling channels 18 are open radially outward. The runner 6 is according to 5 further radially outward from a bandage 19 surround. To optimize the cooling effect has the bandage 19 in the area of the cooling channels 18 recesses 20 on. Alternatively or additionally, the bandage could 19 in the area of the cooling channels 18 also be interrupted.

The generator unit 1 is preferably designed as a synchronous generator. The stand 5 is therefore according to 6 via a converter device 21 with a power grid 22 connected. According to 6 indicates the inverter device 21 while a number of inverter units 23 on. The minimum number is one. But there can also be several inverter units 23 to be available. According to 6 are for example two inverter units 23 present, which are connected in parallel with each other and are electrically operated with a phase offset of 180 ° (= 360 °: 2). There would be more than two inverter units 23 If present, the phase offset would be correspondingly lower. In general, the phase offset is 360 ° / n, where n is the number of parallel converter units 23 is.

By the operation of the inverter described above 21 can be achieved that harmonics the generator unit 1 almost completely extinguished, while the fundamental (network frequency) is maintained. By this measure, currents exceeding the Ma run off to zero potential, almost completely suppressed.

Between the stand 5 and the converter device 21 on the one hand and between the converter device 21 and the power grid 22 On the other hand, according to 6 Filtration devices 24 arranged. Due to such filtering devices 24 On the one hand, it can be achieved that between the converter device 21 and the power grid 22 no suction throttles must be arranged. Above all, though, are the filtering devices 24 Harmonics further subdued. This will make the losses in the stand 5 and in the runner 6 even further reduced.

According to 7 is due to the rotation of the runner 6 in the stand 5 induced a voltage u _p . At the same time flows in the stand 5 a stator current i _q . The stator current i _q is in accordance with 7 an additional current i _d superimposed. The additional current i _d is opposite to that in the stator 5 induced voltage u _p visible by 90 ° electrically out of phase. He is using the inverter device 21 in the stand 5 fed. The superposition of the currents i _d and i _q gives a total current i.

By the additional current i _d is according to 7 causes a field weakening. j is the imaginary unit, x _hd is the reactance, x _{10 is} the leakage reactance of the stator 5 , u _i and u ₁ are the resulting induced voltage and the terminal voltage. According to 7 the terminal voltage u1 of the generator unit drops 1 , Therefore, the inverter device 21 be dimensioned smaller than would be possible without the additional current i _d .

Alternatively, the injection of the additional current i _{d could} also be such that a field amplification is effected. In this case, a reluctance torque can be exploited, so that overall sets a reduced power consumption. Also in this case, the inverter device 21 be dimensioned smaller than would be possible without the feed of the additional current i _d .

According to the 8th and 9 are at the runner 6 permanent magnets 25 arranged. The generator unit 1 So it is a permanently excited generator unit 1 , The permanent magnets 25 are doing according to 8th on U-shaped yokes 26 arranged to the stand 5 are open. The yokes 26 are tangentially spaced from each other. This is in 8th through appropriate air gaps 27 indicated.

Like from the 8th and 9 It can also be seen that the permanent magnets are 25 both axially and tangentially spaced apart. In the axial direction, the spacing can be achieved, for example, that blocks of permanent magnets 25 which are formed by air gaps 28 are separated from each other. Within the blocks, the spacing may vary according to 10 For example, be achieved by the fact that the permanent magnets 25 through adhesive layers 29 are glued together and in the adhesive layers 29 spacer 30 are introduced. As a spacer 30 can, for example, small glass beads 30 serve, which have a diameter in the range between 0.05 and 0.2 mm.

How out 9 It can be seen further, the stand has 5 a stator core 31 is divided on the axial. The axial subdivision of the stator core 31 This corresponds essentially to the block division of the permanent magnets 25 , By this block formation and spacing of the stator core package 31 and the permanent magnets 25 eddy current losses can be decisively reduced.

through the inventively designed wind turbine is a previously unattainable reliability in continuous operation, too reachable in offshore installations.

Claims (8)

Wind turbine, with one of a wind turbine ( 2 ) driven generator unit ( 1 ), which has a stand ( 5 ) and a runner ( 6 ), wherein the stand ( 5 ) in a housing capsule ( 4 ) and the runner ( 6 ) in the housing capsule ( 4 ), the runner ( 6 ) with the wind turbine ( 2 ) via a drive shaft ( 7 ) connected through the housing capsule ( 4 ), and the housing capsule ( 4 ) the stand ( 5 ) and the runner ( 6 ) encapsulates in a high degree of protection, characterized in that the housing capsule ( 4 ) has a cold pole and that the generator unit ( 1 ) a dehumidifier ( 11 ), from which at the cold pole air from the housing capsule ( 4 ), the extracted air is dehumidified and the dehumidified air of the housing capsule ( 4 ) is supplied again at a location remote from the cold pole. Wind power plant according to claim 1, characterized in that the dehumidifying device ( 11 ) outside the housing capsule ( 4 ) is arranged. Wind turbine according to claim 1 or 2, characterized in that the dehumidifying device ( 11 ) on the outside of the housing capsule ( 4 ) is attached. Wind turbine according to claim 1, 2 or 3, characterized in that inside the housing capsule ( 4 ) in areas where there is condensation collect water, collection and discharge channels ( 13 ) are arranged. Wind power plant according to claim 4, characterized in that the collecting and discharge channels ( 13 ) have a gradient of at least two percent, preferably at least five percent. Wind turbine according to one of the above claims, characterized in that the inner half of the housing capsule ( 4 ) arranged elements ( 5 . 6 ) of the generator unit ( 1 ) are rounded off without exception, the rounding offs ( 15 ) have a radius of curvature (r) of at least three millimeters, preferably of at least five millimeters. Wind turbine according to one of the preceding claims, characterized in that the inside of the housing capsule ( 4 ) arranged elements ( 5 . 6 ) with a multi-layer thick-layer protective coating ( 16 ) are painted. Wind turbine according to one of the preceding claims, characterized in that the housing capsule ( 4 ) in the passage area of the drive shaft ( 7 ) by means of a sealing ring ( 8th ), which is spring-loaded against a stop ( 10 ) of the housing capsule ( 4 ) is pressed.