Variable radio frequency electromagnetic compensation device for protecting wind tower blades or other moving or stationary structures

Abstract

To provide means for protecting blades of wind turbine towers having metal elements for collecting electric charges on surfaces and movable or static structures.SOLUTION: An electromagnetic variable-radiofrequency compensator device for protection of blades of wind turbine towers or other movable or static structures comprises: two conductive adapters (1, 2) in which one connection of the device having an external collector of an element to be protected is installed on one side and the other earthing connection is installed on the other side; two elements which are disposed between a first conductive element (7) and a second conductive element (8), connected to the two adapters on both sides of a frequency resonator formed by a dielectric insulator (9), reduce a frequency, absorb a portion of energy generated in a form of heat and have high reactance to a passage of a high-frequency current; and an absorber of the energy in the form of heat.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] As stated in the title of this specification, the present invention refers to a variable radio frequency electromagnetic compensation device for protecting wind tower blades or other moving or stationary structures, which provides advantageously designed functionality and characteristics that are disclosed in detail below.

[0002] The object of the present invention refers to a device that aims to provide a means for protecting wind tower blades and moving or stationary structures, equipped with metal elements for collecting electric charges on its surface, against direct atmospheric discharges, as well as against electromagnetic pulses that may come from atmospheric discharges between positive or negative clouds in the environment close to said means and affect the wind tower blades and moving or stationary structures, and against electromagnetic pulses coming from the radiation of towers or radiating antennas, from telecommunications, from any type of radar or from other sources.

[0003] The field of application of the invention lies in the industrial sector concerned with manufacturing equipment, systems and devices for protecting metallic structures against the collection of electric charges. [Background technology]

[0004] As a reference to the current state of the art, it is necessary to cite at least that the Applicant is not aware of the existence of any other invention having the same or similar technical and structural characteristics as those claimed herein, of any other electromagnetic compensation device having metallic elements for collecting electric charges or for any other similar application, or applied to protect wind tower blades, or other moving or stationary structures.

[0005] The invention proposes a variable radio frequency electromagnetic compensation device for protecting wind tower blades, or other mobile or stationary structures, as previously described, with the purpose of protecting wind tower blades, and mobile or stationary structures, equipped with metal elements for collecting electric charges on their surface, against direct atmospheric discharges, as well as against electromagnetic pulses originating from atmospheric discharges between clouds, either positive or negative, in the environment close to said device, which may affect said wind tower blades, and mobile or stationary structures, and against electromagnetic pulses originating from radiation of towers and radiating antennas, from telecommunications, from any type of radar, or from other sources.

[0006] The apparatus of the present application may be located inside or outside the structure to be protected, depending on the particular case, but is preferably located inside and, in either case, configured to be interconnected between the external collecting elements of the protected structure and earth. When protecting a wind tower blade, the device is located within the blade and is interconnected between the moving or stationary collecting elements of the blade (depending on whether the blade is moving or not) and a connection to earth.

[0007] The protection device is activated when sufficient charge builds up, either of atmospheric origin due to the appearance of electric fields in the surrounding environment or due to constant movement of the charge collecting element, for example the constant movement of a wind tower blade, or the movement of a crane, or the movement of a mobile telescope, and due to electrification of atmospheric origin or due to external origins such as radiant towers or variable radio frequency electromagnetic pulses originating from telecommunications, radars, and first performs a high reactance effect (force against electromotive force) on the passage of high frequency current, converting it into heat, leaving the passage low current, and finally performs compensation of the charge present between the connection to the external moving or stationary collecting element (for example the blade) and the earth connection. The compensation effect is active at a predefined value of the potential difference present in the device, compensating all charges exceeding this potential value and preventing the formation of ascendant markers on the moving or stationary external collecting element.

[0008] The variable radio frequency electromagnetic compensation device that is the object of the present invention is the result of knowledge of the frequency spectrum present in atmospheric phenomena and in electromagnetic pulses generated by atmospheric phenomena and derived from external sources, such as research related to the analysis of resonant modes of variable radio frequencies in various structures, as well as radiation towers, communication, radar, AM, FM signals, etc.

[0009] The design of the device object of the invention was also based on the study of radio frequency electromagnetic field results obtained by simulation on the distribution of electric field E, magnetic field H and surface current density J at different moments of time comparable to each other in the frequency spectrum from 0.4 GHZ to 1.9 GHz. In this case, it was concluded that potential designs of electromagnetic field resonant structures with a main resonant mode at a certain frequency in GHz and almost continuous oblique modes in the remaining frequency spectrum, which achieve the results of the design of the device object of the invention, acting like an electromagnetic radio frequency resonator facilitating electrical discharges, mainly at said frequencies (0.4 GHz to 1.9 GHz). These discharges are caused by the absorption of variable radio frequency electromagnetic fields and the recombination of charges with different signs (mostly positive charges and ions). This is caused by the participative action of static electric and magnetic fields as well as resonant electromagnetic fields at different frequencies. Both actions facilitate the combination of charges as they remain engaged (temporarily trapped) in close confinement zones due to the influence of radio frequency electromagnetic fields, where the action of mobility promoted by electrostatic fields stimulates the compensation of the charges.

[0010] Thus, the operating principle of the device of the invention is that, on the one hand, it acts with high reactance on the passage of high frequency currents, converting them into heat, and passes only low frequency currents, and, on the other hand, it compensates for the variable radio frequency electromagnetic field and acts as a constant sink of variable radio frequency charges from a given potential difference (in the range of 10 to 20 KV).

[0011] These processes take place in the confinement of the device, i.e. in an airtight fire box, but their permanent and almost continuous activity is sensed in the widespread environment, either directly or by electric continuity, in all conductive structures connected to both terminals of the device, because the compensatory processes of homogenization, inter-material conductivity, and thermalization stimulate diffusion between conductive means in the unbalanced local environment.

[0012] Based on the above studies, and keeping in mind that the device has limited electromagnetic compensation capacity, which basically depends on the speed at which the charge accumulated in the moving or stationary collector of the protected structure (for example the blades of a wind tower) is conducted to the device, as well as on the value of the earth resistance to which the device is connected (which must always be less than 10 Ohms to ensure good conduction of the charge to the device), and on the value of the frequency spectrum of the conducted current, by installing this device a variable absorption of low intensity currents flowing to earth is achieved, avoiding the built-in moving of the protected structure or the stationary external collection system from generating ascendant markers (derived from their own movements or from possible variations in the electric field of atmospheric origin), as well as avoiding the coupling of externally radiated variable frequency electromagnetic pulses and possible saturation of the electrostatic charge in said collection device.

[0013] For this purpose, in particular, the device essentially comprises two connecting conductive adapters, one of which is connected to the external collector of the element to be protected and the other to the earth connection, which are charged from the connections of the device, and two elements of high reactance to the passage of high frequency currents and of energy absorption in the form of heat, one element being charged to generate a force against the electromotive force upon the passage of the initial high frequency current, lowering its frequency and absorbing part of the generated energy in the form of heat, which finally reaches the other element, this other high reactance element absorbing the remaining energy and allowing only the low frequency current to pass, after the current has passed through a central system formed by a dielectric insulator placed between both conductive elements and which essentially forms a frequency resonator.

[0014] Furthermore, in a preferred embodiment, the device comprises two supports of insulating material to fix the elements within the box and, secondly, a very important concept, to avoid that the central system of dielectric insulators comes into contact with the walls of the box, in the normal compensation and operation process, such that an electric arc would be formed between the conductive elements of the system.

[0015] In part, the central system constituted by a dielectric insulator and the two conductive elements arranged on either side of it forms a suitable resonator and electromagnetic compensator.

[0016] The box is preferably a waterproof and airtight box with mechanical and fire protection, essential only through connecting conductive adapters placed on the outside on both sides of the box, so that there is no inhalation of charged air or water, which could cause an electric charge to flow in and change the operating conditions of the resonator or cause a loss of insulation, and capable of withstanding the thermal conditions occurring inside, which must withstand up to a minimum of 200°C.

[0017] The device further comprises a series of pressure vent valves built into the box and running from the inside to the outside, which are airtight against humidity and air intrusion and are responsible for removing any internal overpressure in the box so that the same pressure is always applied inside and outside the box, as well as for removing any moisture that may be present in the box and preventing moisture from entering the box.

[0018] Preferably, the box will have four pressure vent valves so that there is no excessive pressure in the box that could destroy it, but such number can vary and depends on the measure and amount of air you are trying to remove. Typically there will be a minimum of two and a maximum of four valves.

[0019] Finally, it should be noted that the disclosed elements of this device can have several geometric shapes, depending on the design and protection requirements for the structure being designed.

[0020] In any case, one premise must be kept in mind that for the variable radio frequency electromagnetic compensation device to operate correctly, the conductive elements arranged on both sides of the dielectric insulator require specific separation, depending on the conductivity of the material used and the insulation degree of said dielectric element.To supplement the description being carried out and to facilitate the best understanding of the characteristics of the present invention, attached to this specification as an integral part thereof, for purposes of explanation and not limitation, is a drawing, represented only by the number 1. [Brief description of the drawings]

[0021] [Figure 1] 1 shows a schematic side perspective view of an example embodiment of a variable compensation device object of the present invention, showing the main parts and elements included, and their configuration and arrangement. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] Looking at the disclosed FIG. 1 and in accordance with the numerals employed therein, one can see non-limiting examples of embodiments of the variable radio frequency electromagnetic compensation device of the present invention, including those described in detail below.

[0023] As can be seen from the figures, the device of the invention is applicable as a system for protection against direct atmospheric discharges on wind tower blades or other moving or stationary structures, as well as on moving and stationary elements for collecting electric charges in general, and against electromagnetic pulses originating from atmospheric discharges between positive or negative clouds in the environment close to the device and that may affect the wind tower blades or other moving or stationary structures, and against radiation from towers or radiating antennas, for telecommunications, any type of radar or for electromagnetic pulses originating from another source, and comprises at least the following essential elements: - two conductive adapters (1, 2) for connection, the first adapter (1) responsible for the connection of the device with the external collector of the element to be protected on one side and the second adapter (2) responsible for the connection with earth on the other side; two elements (3, 4) connected on either side of the frequency resonator (7, 8, 9) and connected respectively to the two adapters (1, 2) with high reactance to the passage of high frequency currents and absorbers of energy in the form of heat: a first element (3) connected to the first adapter (1) and responsible for generating a force against the electromotive force to the passage of a high frequency initial current, lowering the frequency and absorbing part of the energy generated as heat; and a second element (4) connected to the second adapter (2) and responsible for absorbing the excess energy after the current has passed through the frequency resonator (7, 8, 9) and for passing only the low frequency current; - a frequency resonator constituting a suitable electromagnetic compensation device, consisting of a dielectric insulator (9) arranged between first and second conductive elements (7, 8) each of which is connected with a high reactance element for the passage of said first and second high frequency currents and an absorber of energy in the form of heat (3, 4).

[0024] Moreover, preferably, said elements (1, 2, 3, 4, 7, 8 and 9) are integrated into the airtight box (10) so that all of them remain housed and insulated within the airtight box (10), except for the adapters (1, 2) which remain externally located on both sides of the airtight box (10).

[0025] Inside the box (10) there are supports (5) that both fix its internal elements and prevent the frequency resonators (7, 8, 9) from contacting the walls of said box (10) and from insulating material that prevents the formation of electric arcs during its operation.

[0026] Preferably, the box (10) is made of a thermally insulating, waterproof and airtight material, has mechanical and fire protection and can withstand temperatures up to 200°C.

[0027] In addition, the box (10) preferably incorporates a moisture and air tight inside-out pressure vent valve (6) responsible for removing internal overpressure in the box so that there is always the same pressure inside and outside the box, and also for removing any moisture that may be present inside the box and preventing moisture from entering the box.

[0028] Preferably, the box has four pressure vent valves (6), with a minimum of two valves (6). The nature of the present invention and the manner in which it is practiced being fully disclosed, it is believed that it is not necessary to extend the description further to those skilled in the art who appreciate the scope and advantages arising therefrom.

Claims

1. A variable radio-frequency electromagnetic compensation device for protecting wind tower blades or other mobile or stationary structures, applicable as a protection system against direct atmospheric discharges on said wind tower blades or other mobile or stationary structures, and on mobile and stationary elements for collecting electric charges in general, and against electromagnetic pulses that may affect said wind tower blades or other mobile or stationary structures, originating from atmospheric discharges between positive or negative clouds in the environment close to said device, and from electromagnetic pulses originating from tower or radiating antenna radiation, from telecommunications, from any type of radar, or from other sources, two conductive adapters (1, 2) for connection, the first adapter (1) being responsible for the connection of the device with the external collector of the element to be protected on one side, and the second adapter (2) being responsible for the connection with earth on the other side; two elements (3, 4) connected on either side of the frequency resonator (7, 8, 9) and connected respectively to the two adapters (1, 2) with high reactance to the passage of high frequency currents and absorbers of energy in the form of heat: a first element (3) connected to the first adapter (1) and responsible for generating a force against the electromotive force to the passage of a high frequency initial current, lowering the frequency and absorbing part of the energy generated as heat; and a second element (4) connected to the second adapter (2) and responsible for absorbing the remaining energy after the current has passed through the frequency resonator (7, 8, 9) and for passing only a low frequency current; a frequency resonator constituting a suitable electromagnetic compensation device, constituted by a dielectric insulator (9) located between first and second conductive elements (7, 8) each of which connects with said first and second elements (3, 4) of high reactance to said passage of high frequency current and an absorber of energy in the form of heat; A variable radio frequency electromagnetic compensation device for protecting a wind tower blade or other moving or stationary structure, comprising at least:

2. 2. A variable radio frequency electromagnetic compensation device for protecting wind tower blades or other moving or stationary structures according to claim 1, wherein the adapters (1, 2), the elements (3, 4) and the frequency resonators (7, 8, 9) are arranged in an airtight box (10) and all of the elements (3, 4) and the frequency resonators (7, 8, 9), except for the adapters (1, 2) which remain on the outside on both sides, are housed and insulated within the airtight box (10).

3. 3. A variable radio frequency electromagnetic compensation device for protecting wind tower blades or other moving or stationary structures according to claim 2, characterized in that inside the box (10) there are both supports (5) of insulating material to fix the internal elements of the box (10) and to prevent the frequency resonators (7, 8, 9) from contacting the walls of the box (10) and thus preventing the formation of arcs during its operation.

4. A variable radio frequency electromagnetic compensation device for protecting wind tower blades or other moving or stationary structures according to claim 2 or 3, characterized in that the box (10) is made from a waterproof and airtight insulating material with mechanical and fireproof protection capable of withstanding up to 200°C.

5. 5. A variable radio frequency electromagnetic compensation device for protecting wind tower blades or other moving or stationary structures according to any one of claims 2 to 4, characterized in that the box (10) incorporates an inside-to-outside pressure vent valve, airtight against humidity and air ingress, responsible for removing any internal overpressure in the box so that there is always the same pressure inside and outside the box, as well as for removing any moisture that may be present in the box and preventing it from entering the box.

6. A variable radio frequency electromagnetic compensation device for protecting wind tower blades or other moving or stationary structures according to claim 5, characterized in that said box (10) has at least two pressure vent valves (6).

7. A variable radio frequency electromagnetic compensation device for protecting wind tower blades or other moving or stationary structures according to claim 6, characterized in that said box (10) has four valves (6).

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