DE202008011639U1 - oscillation generator - Google Patents

Abstract

Generator adapted for operation on the water surface or in water, comprising:
a stator (2) and
a relative to the stator movable member (12),
wherein the stator (2) or the movable component (12) has at least one induction coil (10) and the respective other element comprises means (28) which generates a magnetic field which is spatially superimposed on the induction coil (10),
wherein the possibility of movement of the movable member (12) relative to the stator (2) is limited to a substantially rectilinear motion, and
wherein the movable member is connected to a buoyancy body (30, 30 ').

Description

The The invention relates to power generation by alternative energy sources.

to Wind power becomes wind energy and solar technology through wind turbines the sun energy as an alternative energy source intensively used. Another alternative energy source is based on the use of ocean currents caused by the tides is caused. For this purpose, in the state of the art tidal power plants known by the seashore can be found. The operating principle was based on the fact that during the High tide lying reservoir flooded with water which is drained by a turbine at low tide. The turbine is more conventional with a generator Type connected to generate electricity.

The However, the principle of the tidal power plant has the considerable disadvantage that for one efficient operation big Tidal differences are necessary. Therefore, such power plants only useful to install in a few geographical places. The effectiveness the other named energy source is also strong by the local Conditions dependent. There is therefore a need for alternative power plants, which more flexible can be used in such places, the not the specific geographical conditions, as before mentioned, realize.

The The invention provides a generator for operation on the water surface or is set up in the water and has a stator as well as a opposite the Stator has movable member, wherein the stator or the movable Component has an induction coil and the other element one Device that generates a magnetic field, that of the induction coil spatially superimposed is, with the possibility of movement the movable component opposite the stator is restricted to a substantially rectilinear motion and wherein the movable member is connected to a buoyant body is.

Of the previously described generator according to the invention allows electricity to generate by the wave motion as they find in the sea is. A wave height of a few meters (between 1 m and 3 m) is sufficient to the movable component by the buoyant body relative to the stator in a straight line and move off. This movement is enough to power more efficiently produce.

According to one preferred embodiment the movable member with the magnetic field generating means provided and the stator has the induction coil. This design has the particular advantage that the electrical connections of the induction coil can be laid permanently. In particular, none Sliding contacts or the like necessary. This is the device particularly low maintenance, which is especially for the operation in the sea of particular Advantage is.

According to one embodiment has the buoyancy body a closed volume filled with gas or other porous material, which corresponding gas inclusions has, is filled. Preferably, the mass and the volume of the buoyant body are so dimensioned that through the water displacement the buoyancy body the movable member which is coupled to the buoyant body is, at least partially above the water surface comes to rest. These embodiment the generator is suitable for operation on the surface where along the generated by the waves stroke of the movable member The straight-line movement is particularly large.

alternative embodiments can but also a buoyancy body Having a lower buoyancy, so that the movable member partially below the water surface lies. Preferably, however, all electrical and / or magnetic Components of the moving component arranged above the water surface. Also Here, the buoyancy bodies are interrupted by periodically changing flow conditions. and moved so that one straight-line motion between the moving part and the stator is caused.

Of the Generator over the water surface has the Advantage that maintenance work easier to perform are.

According to one preferred embodiment the magnetic field generating device generates a magnetic field, its polarity spatially along the rectilinear direction of movement of the movable component changes several times. During the movement of the induction coil along the direction of movement This reverses the current direction several times. The generator generates an alternating current with a periodicity higher than the corresponding periodicity which is the generator driving waves.

According to a preferred embodiment, the magnetic field generating means is formed by one or more permanent magnets in the generator. These permanent magnets are maintenance-free. Preferably, a plurality of permanent magnets are arranged in a ring. For example, a plurality of bar magnets or in cross-section U-shaped magnet is provided, which are arranged in a star shape and within a height relative to the straight-line movement direction with each of the the same polarity inwards.

Preferably several rings of permanent magnets are provided in the generator, a changing one Magnetic field along the linear direction of movement of the movable To produce device.

According to one preferred embodiment changes the polarity of the magnetic field between successive rings, respectively. This allows in a particularly simple way, a magnetic field along the straight line Moving direction of the movable member to produce the polarity in this direction changes several times.

preferred distances between the several rings are about 5 mm to 60 mm, preferably are 10 mm to 20 mm.

According to one preferred embodiment the induction coil of the generator a plurality of spatially spaced coils on. In particular, two or more coils are provided one behind the other.

Preferably The coils each have a distance along the straight line Movement direction, which is different to the spatial Extension is that this magnetic field along the straight line movement direction occupies each with a polarity. According to one preferred embodiment are several induction coils each by a ferromagnetic Spacer spaced. The ferromagnetic spacer sets away in a ferromagnetic core of the coil. Two spacers, adjacent to each adjacent to a coil, have about the distance along the straight line direction of motion, in which the polarity once the magnetic field changes. By This construction can advantageously be a magnetic Flow through Form the core of each induction coil, wherein the magnetic Flow through the ferromagnetishcen spacers to each adjacent permanent magnet of the moving component continues. According to one embodiment is the height including the induction coils the ferromagnetic spacer exactly sized so that he periodicity of the changing one Magnetic field of the movable component corresponds. This embodiment while ensuring a high magnetic flux through the induction coils and thus during movement of the generator for a high Induction voltage. However, this embodiment has the disadvantage that at a standstill of the generator a relatively high magnetic force holds the movable member relative to the stator at a height. This so-called cogging torque inhibits the start of the generator in particular out of a standstill. According to one preferred embodiment is therefore the height including the induction coils their possibly existing spacers so that they something bigger or slightly smaller (up to about ± 20%) as the height, in which is the polarity the magnetic field of the moving component reverses. In this way the cogging torques experienced by the moving component are reduced. Of the Generator can thus already by lower external forces, for example at a lower Swell, to be set in motion. According to another preferred embodiment active means are provided which the cogging torque of the movable Component opposite the Overcome the stator in the initial phase. For example, a compressed air drive may be provided to the movable component initially to set in motion. Once the cogging moments are overcome, the movable Component be kept in vibration by the wave motion.

According to one embodiment the induction coil is coupled to a rectifier. A rectification is preferably suitable for a possibly irregular movement of the movable component due to irregular wave sequences or amplitudes, to generate a current, which then returns to an alternating current is converted to feed it into a power grid. direct current is also particularly suitable to several of the generators to couple with each other electrically.

According to a preferred embodiment, the plurality of coils constituting the induction coil of the stator are each arranged at a distance along the rectilinear moving direction, which is different from the spatial extent occupied by the magnetic field along the rectilinear moving direction, each having a polarization, so that the In each case, the alternating voltage generated in the plurality of coils has a constant phase shift, z. B. 90 ° or 60 °. For this purpose, the distance between two coils in each case has a predetermined ratio to the distance in which the permanent magnets are arranged along the straight-line direction of movement. In this embodiment, in particular, the alternating currents of the plurality of coils can be tapped individually and used for rectification, for example with a star connection or a three-phase bridge circuit, as is known for three-phase alternating current, ie with a phase shift of 60 °. This type of rectification has the advantage that a direct current with a very low residual ripple can be generated. The embodiment with a phase shift of 60 ° is preferred, because it is possible to fall back on known switching to three-phase alternating current. In principle, however, are other phase shifts with even more phases, ie phase shifts less than 60 °, possible. The plurality of coils of the induction coil can also be arranged in groups, with one group each generating alternating voltages with a predetermined phase shift. These embodiments have the advantage that they, as described above, reduce the cogging torques between the movable member and the stator, while the generated AC voltage can still be used very efficiently, because all the coils at each time of the movement of the movable member relative to the stator for Electricity generation can be used.

According to one preferred embodiment the generator has an upper and lower stop on which the straight line Movement of the moving component limited to the stator. Especially preferred are adjustable stops. These allow the Generator to the local conditions, such as Level of sea level, after installing has been.

According to one another preferred embodiment are at the upper and / or lower stop of the movable member or provided at the corresponding stops of the stator facilities, the one restoring force cause between the stator and the movable member. For example can Springs be provided between the stator and the movable Component be compressed when the movable member is the approaching the upper or lower stop. In an alternative embodiment can Also provided magnets on the upper and / or the lower stop be, each with in-phase Poland to move towards each other, whereby also a restoring force exercised becomes. By the restoring force the system is kept in vibration against the magnetic forces the one attraction or cogging moments between the movable member and the stator act. In particular, the system can be tuned that way be that vibration between the movable member and the stator with a middle one expected frequency and mean amplitude of sea waves, that drive the system, are in resonance.

According to one another preferred embodiment of the generator can also provided several groups of magnets and induction coils be, each on a main shaft and one or more harmonics the ocean waves that power the system. ocean waves are for it she's known not only have a frequency with which the largest amplitude of the waves oscillates, but about it also has harmonics that oscillate at lower amplitudes. By the generator with several groups of induction coils or Magnetic field generating devices can both the main shaft as well as the harmonics of the ocean waves are used. For example can the magnetic field generating devices in cylinder geometry with different diameters along the moving component be arranged. Accordingly, the induction coils are on the stator arranged. A group of induction coils or magnetic field generating Devices along a portion of the stator or the movable Component is in each case on the main shaft or a harmonic of the sea waves, that power the system, tuned.

According to one embodiment The stator has a device to underwater or on a platform over Anchor water. The anchoring device can, for example be rigid. However, it can also be a flexible anchoring, for example by a chain, provided between the stator and the seabed be. In this embodiment preferably, the stator also has a buoyant body, So that the The chain between the seabed and the stator remains taut. According to one alternative embodiment is the stator, which itself experiences a buoyancy weighted a weight. Also in this case, the movable component across from the stator is vibrated by the wave motion. One Advantage of this embodiment exists at large Sea depths, because it is not necessary to anchor up to perform on the seabed.

According to one alternative embodiment the generator for it furnished, with a platform, for example, a former oil platform on the sea, in particular rigid, to be connected.

The Invention also relates to a power plant to generate electricity, which several of the going forward includes described generators, which are electrically coupled together. Preferably, this has Power plant a common transfer point for the supply of energy to a power grid, in particular to the public Power on. The entry point may be in the sea, on an offshore platform or installed on land.

According to one embodiment the power plant is complete set up on an offshore platform, with multiple generators in the immediate vicinity of the platform, for example in the vicinity up to one kilometer, in the water and / or on the water surface are.

Further Features and advantages of the invention will become apparent from the following Description of a preferred embodiment clearly.

1 shows an embodiment of a Ge generator in cross section.

2 shows a Prinizpskizze a power plant with only two generators of several are shown.

3 shows a schematic diagram of an alternative embodiment of a power plant with two generators of another type.

4 shows a schematic diagram of another alternative embodiment.

Referring to the 1 an embodiment of a generator for operation on the water surface is shown.

The generator has a stator 2 on, on an outer casing, of which in the sectional drawing only an upper traverse 4 is shown by means of a rod 6 is firmly mounted. The stator 2 is from a tube 8th surrounded, which prevents the ingress of water to the electrically acted components of the generator. The tube 8th is made of an insulator, such as plastic, glass or ceramic. The tube is with one around the stator 2 arranged around movable component 12 connected.

Inside the tube 8th ie at the stator 2 , are at the stake 6 three induction coils 10 attached, wherein the electrical connections of the induction coil is not shown in the present drawing. The electrical connections are, for example, inside the bar 6 led to the outside. The induction coils 10 can be wound in the same direction or in opposite directions. They are interconnected in such a way that the voltages induced by the induction coils add up.

Around the stator 2 around is the movable component 12 arranged along the extension of the tube 8th can move up and down.

The movable component 12 has an outer tube 14 on which the components of the movable component are attached and which provides mechanical protection. At the top of the tube 14 is a guide element 16 provided in the form of a flange which has an internal bore corresponding to the diameter of the tube 8th pointing to the tube 8th to glide along. Furthermore, the guide element defines 16 an upper contact surface 18 and a lower contact surface 20 , which in a straight-line movement along the stator in the uppermost position with a stop 22 and in the lowest position with a stop 24 come in contact. The upper and lower stop 22 respectively. 24 are firmly connected via a plurality of studs (not shown) with the stator and can be adjusted via the studs in height relative to the stator. In this way, an upper or lower limit of the straight-line movement of the movable component 12 opposite the stator 2 simply be set on site. Further, at the lower and / or upper stop 22 respectively. 24 Damping elements, such as. As springs, (not shown) may be provided to the stop of the movable member 12 in the uppermost or lowest position relative to the stator 2 to dampen.

Inside the movable component are several permanent magnets 28 arranged in the form of superimposed rings. Within a ring several permanent magnets are arranged in a star shape, each with the same polarity pointing inwards to form a ring. Two consecutive rings alternate in polarity. On the outside of the permanent magnets 28 is a continuous ferromagnetic material 29 intended. The magnetic field generated by the permanent magnet is at any height of the movable device 12 opposite the stator 2 , the induction coils 10 superimposed. During a movement of the movable component 12 opposite the stator 2 The magnetic field at the induction coil changes in time, so that an AC voltage in the induction coil 10 is produced.

The induction coils 10 are each by a disc-shaped spacer 11 separated, which consists of a ferromagnetic material. The ferromagnetic material settles in a ferromagnetic core 13 the induction coil continues. Together with the ring-shaped permanent magnets and the ferromagnetic material 29 on the outside of the permanent magnets can be a continuous magnetic flux from a permanent magnet 28 to the spacer 11 made of ferromagnetic material, through the ferromagnetic core 13 , to the nearest spacer 11 and to the next adjacent spacer 28 and by the ferromagnetic material 29 form. By the movement of the movable member relative to the stator, the magnetic flux changes periodically. As a result, an alternating voltage is induced in the induction coil.

The distance between the permanent magnets 28 is slightly less than the distance between two spacers in the illustrated embodiment 11 , each attached to an induction coil 10 adjoin. This has the advantage that at the standstill of the generator, not at all induction coils can simultaneously form a magnetic flux. As a result, the holding force that exerts the movable member on the stator is reduced. By this construction, the mechanical resistance is reduced, which is to drive the movable member relative to the stator must first be overcome from a standstill.

Instead of the illustrated embodiment, the periodicity of the magnetic field, ie the distance between the permanent magnets 28 greater than the height of the induction coils are selected to reduce the previously described cogging torques. The advantage of the construction always occurs when the height of the induction coils is slightly different from the spatial extent with which the magnetic field of the moving component changes.

At the lower end of the moving part 12 is a buoyant body 30 provided in the form of an annular closed gas volume. This buoyancy body is dimensioned so that the movable member undergoes such buoyancy, so that a part of the movable member protrudes from the water surface. The buoyancy body 30 is tuned in volume to the specific gravity of seawater.

During operation of the system, a wave motion on the sea surface generates a periodic up and down movement of the moving component 12 opposite the stator 2 , This "free" energy source keeps the generator running and, thanks to its relatively simple design, is designed to operate in the water without major maintenance.

The generator stroke can be several meters according to local conditions. For example, the maximum movement of the movable member relative to the stator is limited to 3 m to 5 m. It can also be provided that the magnetic field of the movable member in the uppermost or lowermost position of the movable member also above or below one or more induction coils 10 extends.

Like in the 2 Shown as a schematic diagram, several of the generators can share a common platform 32 be anchored. The platform 32 is rigidly connected to the seabed. It may, for example, be an oil platform, which has been converted accordingly after decommissioning. The fastening of generators of the platform 32 in the 3 is shown only schematically, is arranged so that the electrical and magnetic components of the generators approximately above the water surface 34 to come to rest.

Each of the generators is assigned a rectifier (not shown), either on the platform 32 or on the generator itself, which rectifies the alternating current generated by the generator. The DC currents of the generators are on the platform 32 brought together and can be led ashore.

3 shows a schematic diagram of a variant of the power plant previously described. In this power plant, another type of generator is used, which is set up to operate partially below the water surface. The buoyancy body 30 ' of the moving component is configured for underwater operation. The water flows in the horizontal direction corresponding to the waves, as they are perceived on the water surface, he testifies in these generators, a periodic movement of the buoyant body or of the movable component 12 opposite the stator 2 ,

The anchoring of the generators can also be done directly on the seabed as in the 2 and 3 shown. The connection to the seabed can be rigid, or, as in the 2 and 3 shown, flexible z. B. by a rope or a chain, possibly with a counterweight 31 ,

In a further alternative embodiment, the stator is not connected to the seabed 36 or with a platform 32 connected. In this embodiment, the stator is 2 only with the platform 32 connected. The buoyancy body 30 '' is how in 4 shown, completely closed, so that no water from below into the movable component 12 can penetrate.

Furthermore, it can be provided that the height of the stator 2 compared to the mean sea level, ie the sea surface without wave motion, adapted to z. B. compensate for the influence of tides.

Further alternative embodiments of the present invention within the scope of the following claims possible.

2

Stator (includes: 6 . 10 . 11 . 13 )

4

crossbeam

6

pole

8th

tube

10

induction coil

11

spacer

12

Movable component (includes: 8th . 14 . 16 . 18 . 20 . 28 . 29 . 30 )

13

Plunger

14

tube

16

guide element

18

Upper contact surface

20

Lower contact surface

22

Oberer attack

24

lower attack

28

permanent magnet

29

ferromagnetic material

30 30 ', 30' '

buoyancy

31

flexible Attachment with counterweight

32

platform

34

sea

36

lower Counter storage (eg seabed)

Claims (22)

Generator adapted for operation on the water surface or in water, comprising: a stator ( 2 ) and a relative to the stator movable member ( 12 ), wherein the stator ( 2 ) or the movable component ( 12 ) at least one induction coil ( 10 ) and the other element is a device ( 28 ), which generates a magnetic field, that of the induction coil ( 10 ) is spatially superimposed, wherein the possibility of movement of the movable component ( 12 ) opposite the stator ( 2 ) is restricted to a substantially rectilinear movement, and wherein the movable member with a buoyant body ( 30 . 30 ' ) connected is. Generator according to claim 1, wherein the movable component ( 12 ) the magnetic field generating device ( 28 ) and the stator ( 2 ) the induction coil ( 10 ) having. Generator according to one of the preceding claims, wherein the buoyant body ( 30 . 30 ' ) has a closed volume filled with gas or a porous material having gas inclusions. Generator according to one of the preceding claims, wherein mass and volume of the buoyant body ( 30 ) is dimensioned and arranged so that all electrical and / or magnetic components of the movable component come to lie above the water surface. Generator according to one of the preceding claims, wherein the device generating the magnetic field ( 28 ) generates a magnetic field whose polarity changes spatially several times along the rectilinear movement direction of the movable component. Generator according to one of the preceding claims, wherein the device generating the magnetic field ( 28 ) has one or more permanent magnets. Generator according to claim 6, wherein a plurality of permanent magnets ( 28 ) are arranged annularly. Generator according to claim 7, wherein a plurality of permanent magnets ( 28 ) formed rings are arranged one above the other along the straight-line direction of movement Generator according to one of claim 8, wherein the permanent magnets ( 28 ) each have a ring of a uniform polarity facing inward and the polarity reverses between successive rings, respectively. Generator according to claim 8 or 9, wherein the plurality Rings a distance between about 5 mm and 60 mm, preferably between 10 mm and 20 mm. Generator according to one of the preceding claims, wherein the induction coil ( 10 ) is formed by a plurality of spatially spaced coils. Generator according to claim 11 with reference to claim 5 or any claim dependent thereon, wherein the plurality of coils ( 10 ) each have a distance along the rectilinear movement direction, which is different from the spatial extent, which occupies the magnetic field along the straight-line movement direction, each having a polarity. The generator of claim 12, wherein the plurality of coils or one or more groups of the plurality of coils at a distance along the rectilinear movement direction are arranged, the one predetermined ratio corresponds to a constant distance with which the magnetic field generating Arrangements arranged along the straight-line direction of movement are so that in the Operation of the generator by the multiple coils or the group or the groups of the plurality of coils each having an alternating current constant phase shift is generated. Generator according to one of the preceding claims, wherein the induction coil ( 10 ) is coupled to a rectifier. Generator according to one of the preceding claims, wherein the rectilinear movement by an upper and a lower stop ( 22 ; 24 ) is limited, which are adjustable in height in particular. Generator according to claim 15, wherein the upper and / or the lower stopper is provided with a device which a restoring force on the movable member ( 12 ) exercises when the movable component ( 12 ) approaches the stop. Generator according to one of the preceding claims, wherein the stator ( 2 ) has means for anchoring underwater or on a platform above water. Power plant for power generation, the multiple generators according to one of the preceding claims, which are electrically connected to each other are coupled. Power plant according to claim 16, which has a transfer point provides for the supply of energy in a power grid. Power plant according to claim 18 or 19, which is a Device for converting the generated by the plurality of generators streams in an alternating current with a uniform phase. Power plant according to claim 20, which contains the alternating current with uniform phase generated from direct current, of the several Generators is provided. Power plant according to one of claims 18 to 21, which is completely installed on an offshore platform ( 32 ), the multiple generators surrounding the platform ( 32 ) in the water and / or on the water surface ( 34 ) are set up.