MXPA00000682A - Wind energy installation - Google Patents

Abstract

The invention relates to a wind energy installation comprising a rotor with at least one blade for the conversion of wind flow energy into mechanical energy, a regulating device for individual regulation of at least one rotor blade, a generator for the conversion of mechanical energy provided by the rotor into electric power, and an active connection between the rotor and the generator so that the mechanical energy can be transferred from the rotor to generator. The aim of the invention is to avoid such problems as those mentioned in the description and to provide a wind installation whereby the loads which can occur in partial areas of the surface of the rotor as a result of local transitory peaks in wind speeds are reduced. This is achieved by providing the above-mentioned wind energy installation with means of measurement such as an anemometer (44) placed on each rotor blade to determine the momentary load of one part of the wind energy installation, in addition to control means which determine a desired position for at least one rotor blade in order to react to said momentary load and to adjust the rotor blade accordingly using the regulating device, as well as joints and fasteners which connect the regulating device and means of measurement to the control means.

Description

EOLIC APPARATUS DESCRIPTION OF THE INVENTION: The invention relates to a wind power installation that comprises a rotor with at least one rotor blade to convert the kinetic energy of the wind into mechanical energy, an adjustment device for the individual adjustment of at least one a rotor blade, a generator to convert the mechanical energy of the rotor into electrical energy and an operative connection between the rotor and the generator to transmit the mechanical energy of the rotor to the generator. Wind energy installations of this kind are part of the current state of the art. For example the reference book "Windkraftanlagen" by Erich Hau, Springer Verlag 2nd edition 1996, pages 52, 175,222 to 242, 269 and 320 shows installations of that class. In these wind power installations, the rotation speed of the rotor and the energy produced can be regulated by means of a regulation system for the angle of incidence of the rotor blade. Furthermore, the known system of regulating the angle of incidence serves to protect the rotor from rotating at an excessive speed in the event that the wind has high speeds or in the case of a major failure where the moment of the generator disappears suddenly. Both cases include protecting the power installation REF: 32484 wind from damage due to the rotor rotating at excessive speed. In this aspect there are two ways to produce a reduction of the rotor speed, by means of the adjustment of the rotor blade; On the one hand, the angle established for the blade can be reduced in the direction of a lower angle of incidence in order to reduce the energy consumption of the rotor. On the other hand it is possible to achieve the aerodynamic angle of the angle of incidence, the so-called stable condition, by adjusting the angle of the rotor blade at greater angles. The last option gives the advantage of an adjustment in a shorter distance, but brings with it the disadvantage of the arrest produces higher loads for the rotor and the entire wind power installation. A common aspect of both adjustment options is, however, to take into account only an average velocity of the wind speed acting on the entire wind power installation, or a certain rotational speed of the rotor, as an initiation signal to establish an angle of rotor blade. A wind power installation is presented in GB-A-2-067 247. According to this publication, wind power is average in the rotor plane of the wind power installations by means of pressure tests that are arranged in the surface of the rotor blades in the vicinity of the profile nose. In that publication the measured values obtained in this way are used among other things to pivot the rotor plane of a wind energy installation until the measured values are the same for rotor at 90 and 270 °. Another wind power installation is known by the U.S. No 4297 076. The wind turbine presented in a machine controlled by stability, the main rotor blades of the known installation are fixedly connected to the hub and are not rotatable about its longitudinal axis. The main loads in the main axis of the installation are produced by the non-rotatable components of the rotor blades. The above-mentioned options in the current state of the art do not take into account that particularly when a large diameter rotor is used, there may be a non-uniform distribution of wind conditions over the rotor area. This in turn results in different loads on the individual rotor blades as well as non-symmetrical loads for the drive train of the wind power installation, ie the hub, the drive shaft and the respective bearings or supports. Asymmetric loads of that kind do not occur however only from a given speed of rotor rotation or a given wind speed, but they take place continuously during the normal operation of the wind power installation. The regulation of the angle of alabe known up to now by the state of the art can not react to fluctuations in wind speed and load fluctuations, which are related to the above, in the region of the rotor, since known installations they provide a uniform synchronous adjustment of the rotor blades. In more modern installations (see in particular page 238 of the book to which we have referred), on the one hand it is proposed to perform an individual electrical adjustment of each individual blade, however such a proposal is also based on the assumption of an average speed of wind acting on the wind power installation. With that and the other assumption that the wind velocity increases with height, the proposition is then for a fixed cyclic or rotational correction of the angle of incidence of the rotor blade in order to be able to at least partially regulate the loads changing with the increase in wind speed with height. This method of establishing the rotor blade also suffers from the disadvantage that the angle of incidence of the rotor blades is fixed predeterminedly and therefore can not react to temporary, local changes in wind speed over a part of the rotor . For this purpose, therefore, an asymmetric load is also presented on the components of the wind energy installation, which thus reduces the operational life of the same. The object of the invention is therefore to avoid the aforementioned problems and provide a wind power installation that reduces the loads that may occur under local temporary summits in the wind speed in portions of the rotor area According to the invention that object is achieved because a wind power installation of that kind in the descriptive part , measurement means are provided to investigate the instantaneous loading of a part of the wind power installation, control means to know the position of at least one rotor blade, knowing the instantaneous mechanical load and to properly adjust the rotor blade by means of the adjusting device, and connecting means for connecting the adjusting device and the medi measuring the control means. The wind power installation according to the invention makes it possible by means of the adjustment device of at least one rotor blade, that the wind energy installation is adapted by the control means to the instantaneous loads that are locally presented in only one part of the wind power installation, such loads are known by the measuring means. This advantageously provides that the local peaks in the load on the rotor blades, hub and drive shaft and supports can be avoided. . This in turn has the consequence that the service life of the wind power installation will increase, and is not intentionally reduced by the asymmetric loads of parts of the wind power installation, which cause the service life of the wind power to be reduced. the same, which is substantially avoided. Furthermore, the installation of wind energy according to the invention allows an optimal use to be made of the instantaneous distribution of wind speeds over the rotor area and thus makes it possible to contribute to an increased energy output from the wind power installation and that all the rotor blades are always operated with and at the optimum angle of the blade and therefore the efficiency level for each blade of the rotor rises in comparison with the efficiency of wind power installations in the current state of the art. It is particularly preferred for the position of the blade or blades of the rotor that they adapt without interruption to the instantaneous loading of the wind power installation. In this way it is possible to ensure that the wind power installation operates continuously in its optimum working range and at the same time is protected from peaks or load peaks, triggered due to the wind speed peaks that occur locally in the rotor region. In a preferred embodiment of the invention, the measuring means for evaluating the local load on a rotor blade evaluates a wind speed obtained in the rotor blade. For this purpose the measuring means preferably have an anemometer mounted on the rotor blade, by virtue of the fact that the anemometer is arranged directly on the rotor blade, it is possible to achieve a highly accurate control of the angular position of the rotor blade. as a reaction to an increased or decreased wind speed. For the measurement of the wind speed directly at the place where the adjustment of the wind energy is presented, directly directly on the blade or rotor blade to be adjusted, a fast adaptation of the angular position of the blade is allowed from the rotor to local variations in wind speed. Another preferred embodiment is characterized in that the measurement evaluates a mechanical load that prevails in a portion of the rotor region. In this embodiment, direct evaluation of the mechanical load occurs in a portion of the rotor providing the control means with accurate information, by means of which the control means can evaluate a desired position of at least one adjustable blade or blade of rotor, taking into account the predetermined data with respect to the load and / or material geometry. It is particularly advantageous in this embodiment that the measuring means can evaluate a mechanical load prevailing in the adjustable rotor blade. Because by the load that is evaluated directly on the rotor blade, very accurate information about the profile of the wind force on the rotor area can be obtained, in a similar way to the procedure discussed above to directly evaluate the wind speed in the rotor. the rotor blade. With that similar information, the control means are then able to control a particularly accurate reaction on the part of the adjusting device, so that a tip or load peak existing in a portion of the rotor can be rapidly reduced. Another embodiment of the invention with a rotor hub for carrying the rotor blades has measuring means that measure a mechanical load presented in the rotor hub. This mode also allows a quick adaptation of the rotor blades to the altered load situation. The same applies to embodiments with a reinforcement shaft or portion of shaft to support the rotor, wherein the measuring means evaluates a load prevailing in the reinforcement shaft, and in the case of a wind power installation having a drive shaft that connects the rotor and the generator directly or by means of a transmission, where the measuring means evaluate a load that prevails in the drive shaft or in the drive shaft supports or the reinforcement shaft or portion of axis. All the aforementioned modes allow an exact detection of the local load conditions in the rotor region and thus an exact control of the adjustment device by means of the control means. It is this aspect that is particularly preferred ifThe measuring means for measuring the mechanical load have strain gauges which are mounted on the respective loading parts of the wind power installation. This means that the strain gauges can be mounted on the blade or rotor blade, inside the blade, or on the rotor hub or inside the rotor hub, or on the reinforcement shaft or inside it , on the drive shaft or inside it, or on the bearings or supports. In all the above-mentioned ways of mounting the strain gauges, it is easily possible to determine the mechanical load involved and thus individually adjust the rotor blade according to the invention. Another preferred embodiment of the invention has measuring means that evaluate an angle of wind influx 5 that prevails in the rotor blade to be adjusted. By virtue thereof, it is also possible advantageously to determine the direction of the inflow of wind flow with respect to the rotor blade to be adjusted. By means of this measurement value, the control means can also be react to a change in wind direction that occurs in a portion of the rotor. Particularly in conjunction with the aforementioned load measuring means, the control means have a very accurate picture about the wind conditions momentary over the area of the rotor: by virtue of the load measuring means the control means can take into account an absolute load that is present and furthermore by virtue of the measuring means determine the inflow angle- having relation with the The current position of the blade can also provide an exact determination of the magnitude of the angle to be adjusted, an adequate adaptation to the rapidly changing wind conditions is thus advantageously ensured by the combined use of the inflow angle and the load measurement in the rotor blades. In this aspect, it is particularly preferred to measure the inflow angle to be effected by a wind vane or an indicator mounted on the rotor blade. Another preferred embodiment of the invention is distinguished in that a portion of a rotor blade is asynchronously adjustable with respect to at least one adjustable portion of another blade or blade of the rotor. Thus, particularly when dealing with very long rotor diameters, it is possible to reduce the level of the structure of the apparatus and the expense with regard in particular to the outer portion of the rotor blade is adapted to be adjustable, such as power generation of the rotor It is basically concentrated in the outer region of the In an advantageous embodiment of the invention the position of the rotor blade, which is desired for instantaneous loading, can be predetermined by means of consumption means connected to the control means. In this way, the wind energy installation according to the invention can be adapted in the place after the erection for possible unforeseen wind conditions or after repair to modify the size of the material or the profiles of the rotor blades. It has been found particularly advantageous for the current value of the angular position of the rotor blade to be detected by an adjustment transmission, which, with the adjustment motor, forms the adjustment device. In this respect, it is particularly advantageous if the control means effect the adjustment of the rotor blade practically simultaneously with detection of the measurement values of the strain gauges, the anemometer or the wind flap or indicator, after comparison with the current or actual value of the adjustment driver, by means of the adjustment motor. Such an instantaneous reaction with respect to changes in the load in the region of the rotor blades, ensures that harmful loads or loads on one side of the rotor will be effectively avoided. An advantageous method for adapting a wind power installation to the instantaneous loads that prevail only in a local portion of the wind power installation is characterized in that the instantaneous loading of a part of the wind power installation is detected by measuring means. and a position of at least one of the rotor blades, which is desired for instantaneous loading, is evaluated by the control means and the rotor blade is properly adjusted by means of the adjustment device, wherein the adjustment device and the measuring means are connected to the control means by means of connection means. This simple process makes it possible to achieve an effective increase in the life of wind energy staging. Further advantageous configurations of the invention are indicated in the appended claims. An embodiment of the invention will now be described with reference to the accompanying drawings, in which: Figure 1 shows a partial section through the wind power installation according to the invention; and Figure 2 is a front view of a wind power installation according to the invention; Figure 3 is a block circuit diagram depicting control of the adjustable blade in a preferred embodiment of the invention. Figure 1 shows a partial sectional view of a wind energy installation 1. The wind power installation 1 is supported on a tower 2 of which only a part is shown. A box 4 fits over tower 2 at the upper end thereof. A maintenance platform 6 that is mounted on the tower is arranged below the box 4. At its back that is closed in the drawing and shown on the right, the box 4 has a generator (not shown) and a device of control 8 shown with a broken line. The generator is behind a bulging portion that extends rearwards 1Q- of the box 4 and is flange mounted by its generator rotor member (not shown) to the hub of the rotor 14 by means of connecting elements 12. The hub of the rotor 14 and the rotor blades 169 only partially shown together form the rotor 18 of the installation. The rotor 18 is supported with its rotor hub 14 by means of bearings 20 on a reinforcing shaft 14 or shaft portion 22. The shaft 22 projects through the hub of the rotor 14, extending through an opening 24, which it is provided in the rotor hub 14. At its end towards the tower 2, the reinforcement shaft 22 is connected to the tower 2 inside the box 4. From the tower 2 which is basically vertical erect, the shaft 22 projects into a position slightly inclined upwards with respect to the horizontal. The shaft 22 is connected to the stator (not shown) of the generator and projects through the rotor member of the generator and through the opening 24 in the rotor hub 14, and after extending out of the opening 24, on the side of the rotor 18 which is remote from the tower 2, is closed by a closing portion 26. The rotor blades 16 in turn extend outwardly in relation perpendicular to the axis of the shaft 22. In that arrangement the rotor blades 16 pass through. through openings 28 in the front case 30. The front case 30 is movably connected with respect to the case 4 which is fixedly connected to the tower 2, and is fixedly connected to the hub 14. The rotor vanes 16 are connected to the hub of rotor 14 rotatably about the longitudinal axis thereof, by means of a flange connection 32. An adjustment motor 34 is mounted on the flange connection 32 and adjusts the rotor blade 16 by means of an adjustment transmission 36. The adjustment motor 34 and the adjustment transmission 36 are connected to the control device 8 by means of the electrical connections 50 and 46 respectively shown in Figure 3. The front box 30 encloses the hub of the rotor 14 with the bearings or supports 20, the flange connection 32, adjusting motor 34 and adjusting transmission 36, in a weather-tight manner. The front case 30 has a substantially hemispherical shape in the cross section. The strain gauges 38 are arranged in the shaft 22. The calipers 40 are arranged in the rotor hub 14. The strain gauges 38 are connected to the control device 8 by means of an electrical connection 42. The strain gauges 40 are connected to the control device 8 by means of an electrical connection 48, which is shown in Figure 3. Figure 2 shows parts of the wind power installation of Figure 1, as viewed from one side of the rotor, Figure 2 shows the tower 2 with the rotor hub 14 mounted on its tip. Three rotor blades 16 extend in a star configuration from the rotor hub. The vanes 16 are connected to the rotor hub 14 by means of the flange connections 32. In order to maintain the clarity of the pattern, the front case 30, the adjustment motor 34, the adjustment transmission 36, the reinforcement shaft 22, the opening 24 and the closing portion 26 of Figure 1 are not illustrated. Mounted on the rotor vanes 16 are indicators or fins 44 for measuring the angle of inflow of wind found by the rotor vanes 16. The vanes 44 are connected to the control device 8 (Figure 1) by means of the electrical connection 52 shown in Figure 3. Reference will now be made to the block circuit diagram of Figure 3 to describe hereinafter the mode of operation of the wind power installation according to the invention. During operation of the wind power installation l the rotor 18 rotates about the axis of the shaft 22. In that state the vanes 16 are at a given angular position which is predetermined by means of the control device 8., the adjusting motor 34 and the transmission 36, with respect to the plane in which the rotor blades are rotating, properly the plane of the rotor. The instantaneous instantaneous angle of the rotor blades 16, with respect to the rotor plane, is communicated to the control device 8 by the adjustment transmission 36 as the current value of the instantaneous position of the rotor blade 16, by means of an electrical connection 46. At the same time the control device 8 receives from the strain gages 38 which are fixed to the shaft 22, by means of the connection line 42 ('load signal of the reinforcement shaft 1 in Figure 3') . Also simultaneously with the communication of the instantaneous adjustment angle of the rotor blades 16, the control device 8 receives from the strain gauges 40 on the rotor hub, by means of the line 48, measurement values in relation to the current load of the rotor hub 14 (ie cube load 'in Figure 3). If by means of the calibrators of 'effort 38, 40, the control device 8, detects a load of one side on the rotor, then, taking into account the instantaneous adjustment angle a1I? at? tM1J of the rotor blades 16 and the inflow angle instantaneous ß detected by the wind vane 44, the control device 18 passes a Q-numeral signal through the line 50 to the adjusting motor 34, to adjust the corresponding rotor blade 16 by the difference? fnußvo-Q! i? t »Anterior • In view of the fact that the control device 8 continuously receives the measurement values of the strain gauges 38 and 40 and virtually instantaneously, taking into account the inflow angle β which is also continuously communicated to the device of control 8, by means of the connecting line 52, the outputs of the working command to the adjusting motor 34, to establish a new angle of the rotor blades 16, the adaptation of the position of the rotor blades 16 occurs in line with a change io under load conditions in the rotor region, and so there is compensation for the asymmetric loads on the rotor 18. As an alternative for the measurement of the instantaneous load on the wind power installation by means of the strain gauges on the rotor hub and reinforcement shaft, it is also possible to provide load measurement directly on the rotor blades by suitable strain gauges. Finally, it should be distinguished that the different signals (this is' the cube load signal 40, 'the tree load signal 38', 'alpha instantaneous angle' 46, and the inflow angle signal ß 53) which are used to evaluate At ideal rotor blade angle they can be used together or alternatively.

It is noted that in relation to this date, the best method known to the applicant to carry out the aforementioned invention is that which is clear from the present description of the invention.

Claims (22)

1. CLAIMS Having described the invention as above, the content of the following claims is claimed as property: l.- A wind power installation comprising a rotor having at least two rotor blades rotatable about the longitudinal axis, adjusting device for individually adjusting a rotor blade to a desired angle of placement of the blade, a generator operatively connected to the rotor, characterized in that means are provided by which the instantaneous mechanical load is evaluated on a part of the wind power installation, control means are provided which evaluate a desired angle position of the blade for the reduction of an instantaneous load or which evaluate a variation in the angle position of the instant blade of at least one blade of the rotor and correspondingly adjust the blade of the rotor the desired angle of the wing angle by means of the adjustment device asynchronously a of the angle of alabe established in the other blade or in the other rotor blades, and the adjusting device and the measuring means are connected to the control means.
2. 2. - A wind power installation according to claim 1, characterized in that the position of the blade or blade of the rotor or of the rotor blades is continuously adjusted to the instantaneous load in the wind energy installation.
3. 3. A wind power installation according to any of the preceding claims, characterized in that the measuring means for evaluating the load on the rotor blade evaluate a prevailing wind speed in the rotor blade.
4. 4. A wind power installation according to claim 1, characterized in that the measuring means for measuring the wind speed has an anemometer
5. 5. - A wind power installation according to claim 4, characterized in that the anemometer is arranged on the rotor blade.
6. 6. A wind power installation according to one of the preceding claims, characterized in that the measuring means evaluate a mechanical load that prevails in a portion of the rotor.
7. 7. A wind power installation according to one of the preceding claims, characterized in that the measuring means evaluates a load that prevails in an adjustable portion of the rotor.
8. 8. - A wind power installation according to one of the preceding claims, characterized in that the measuring means evaluates a load that prevails in the adjustable rotor blade. *. * # r - * -, *. - ****.
9. 9. - A wind power installation according to one of the preceding claims, characterized in that the measuring means evaluate a load that prevails in the rotor hub.
10. 10. - A wind power installation according to one of the preceding claims, having a reinforcement shaft for supporting the rotor, characterized in that the measuring means evaluates a load that prevails in the reinforcement shaft.
11. 11. - A wind power installation according to one of the preceding claims, having a drive shaft that connects the rotor and the generator directly or by means of a transmission, characterized in that the measuring means evaluates a load that prevails in the drive shaft.
12. 12. A wind power installation according to one of claims 6 to 11, characterized in that the measuring means for measuring the load have stress gauges.
13. 13. - A wind power installation according to one of the preceding claims, characterized in that the measurement means evaluate an angle of wind influx that prevails in the rotor blade to be adjusted.
14. 14. - A wind power installation according to one of the preceding claims, characterized in that the measuring means for measuring the inflow angle have a wind vane mounted on the rotor blade.
15. 15. - A wind power installation according to one of the preceding claims, which has at least two rotor blades characterized because at least one of the rotor blades is asynchronously adjustable with the other blades or blades.
16. 16. - A wind power installation according to one of the preceding claims, characterized in that at least a portion of at least one rotor blade is asynchronously adjustable with respect to at least one other adjustable portion of the rotor blade itself, or with respect to the other blade or the other rotor blades.
17. 17. A wind power installation according to one of the preceding claims, characterized in that the position of the blade of the rotor or of the rotor blades that is desired for an instantaneous load can be preset by means of the action means that are connected to the control means.
18. 18. - A wind power installation according to one of the preceding claims, characterized in that the adjusting device for adjusting the rotor blade has an adjustment motor and a transmission that is driven by it, wherein the means of The control receives from the adjustment transmission a current value with respect to the instantaneous position of the rotor blade and adjusts the rotor blade by means of the adjustment motor.
19. 19. A wind power installation according to claim 18, characterized in that the control means implements the adjustment of the rotor blade virtually simultaneously with the detection of the measured values.
20. 20. A wind power installation according to one of the preceding claims, characterized in that the wind energy installation is of the horizontal axis type.
21. 21. A wind power installation according to one of the preceding claims, characterized in that the rotor is a rotor on the wind side.
22. 22. - A process for the operation of a wind power installation according to one of the preceding claims wherein the instantaneous loading of a part of the wind energy installation is evaluated by means of measurement, a position of angle of alabe that it is desired for the reduction in instantaneous loading or a variation in the instantaneous position of the blade angle of at least one rotor blade is evaluated by the control means, and to reduce the instantaneous load the corresponding rotor blade is put on the desired angle asynchronously with respect to the other or other rotor blades. SUMMARY OF THE INVENTION The invention relates to a wind power installation with a rotor with at least one blade or rotor blade to transform wind current energy into mechanical energy, with an adjustment device for individual adjustment of at least one a rotor blade, with a generator for the transformation of the mechanical energy of the rotor into electrical energy and with an action joint between the rotor and the generator for the transmission of the mechanical energy from the rotor to the generator. It is the task of the invention to avoid the aforementioned problem and have a wind power installation, where it is reduced to the load, which due to local and changing points or peaks of the wind speed may occur in partial regions of the surface of the wind. rotor. This problem is solved according to the invention, because in a wind energy installation of the mentioned type an anemometer (44) which is a measuring means of the aforementioned type is provided in the rotor blade, obtaining the momentary effort on a part of the rotor. the installation of wind energy. Steering means are provided, which obtain for the momentary effort the desired position of at least one of the rotor blades and the rotor blade with the help of the adjusting device is adjusted accordingly and connection means are provided, which connect the adjustment and the means of measurement with the means of control or government.