Variable electromagnetic compensation devices for protecting wind tower blades or other mobile or stationary structures.

Abstract

DEPCT65 Variable electromagnetic compensation devices for protecting wind tower blades or similar structures. Mobile or other static type consisting of: two conductive adapters for connection (1,2) charging One (1) of the device's connections to the external collector of the component shall be protected on the side. One and the other (2) of connection with the world in another way and two components of high reaction to The flow of high-frequency current and the energy absorber in the form of heat (3,4) connected on both sides of the body. Reflecting the frequency consisting of a dielectric insulator (9) placed between the first and second conductor components (7, 8) and in sequence to two adapters (1,2) causing an electromotive force to be applied to the high frequency current path. Start by reducing the frequency and absorbing a portion of the energy generated from the heat. -----------------------------------------------------------

Description

[0001] Variable Radio Frequency Electromagnetic Compensating Device for the Protection of Wind Turbine Blades or Other Mobile or Static Structures

[0002] DESCRIPTIVE MEMORANDUM

[0003] OBJECT OF THE INVENTION

[0004] The invention, as stated in the present descriptive memorandum, refers to a variable radio frequency electromagnetic compensating device for the protection of wind turbine blades or other mobile or static structures, which provides advantages and characteristics to the function for which it is intended, which are described in detail below.

[0005] The object of the present invention is a device whose purpose is to provide a means for the protection of the blades of wind turbine towers and of mobile or static structures that have metallic elements for capturing electrical charges on their surface, against direct atmospheric discharges, as well as electromagnetic pulses that may affect them from atmospheric discharges between clouds, positive or negative, in their immediate environment and from those that come from emissions from radiating towers or antennas, telecommunications, radars of any type or other origin.

[0006] FIELD OF APPLICATION OF THE INVENTION

[0007] The field of application of the present invention falls within the sector of the industry dedicated to the manufacture of apparatus, systems and devices for the protection of metallic structures against the capture of electrical charges.

[0008] BACKGROUND OF THE INVENTION

[0009] With reference to the current state of the art, it should be noted that, at least as far as the applicant is concerned, there is no knowledge of any other electromagnetic compensating device, nor any other invention applicable to the protection of wind turbine blades or other mobile or static structures with metallic elements for capturing electrical charges or for any other similar application, that has technical and structural characteristics equal to or similar to those of the one claimed herein.

[0010] EXPLANATION OF THE INVENTION

[0011] The variable radio frequency electromagnetic compensating device for the protection of wind turbine blades or other mobile or static structures proposed by the invention, as previously mentioned, has as its purpose the protection of wind turbine blades and mobile and static structures that have metallic elements for capturing electrical charges on their surface, against direct atmospheric discharges, as well as electromagnetic pulses that may affect them from atmospheric discharges between clouds, positive or negative in their immediate environment and from those that come from emissions from radiating towers or antennas, telecommunications, radars of any type or other origin.

[0012] The device covered by this patent can be placed inside or outside the structure to be protected, depending on the specific case, although it is preferably placed inside and, in any case, interconnected between the external sensors of the structure to be protected and the grounding connection. For the protection of a wind turbine blade, the device is placed inside the blade and interconnected between the moving or stationary sensors (depending on whether the blade is moving or not) and its grounding connection.

[0013] The protection device is activated when a sufficient accumulation of electrostatic charge appears, whether of atmospheric origin due to the appearance of an electric field in its immediate surroundings or due to electrification caused by the constant movement of the elements that capture electrical charges, such as the constant movement of the blades of the wind turbine or the movement of a crane or a mobile telescope, and electromagnetic pulses of variable radio frequency, of atmospheric origin or from external sources such as radiating or telecommunications towers, radars, etc., first performing a high reactance effect (counter electromotive force) to the passage of the high frequency current, converting it into heat and allowing the passage of the low frequency current, to finally compensate for the existing charges between the connection to the external mobile or static capturing elements (for example, the blades) and the grounding.The compensation effect is activated at a certain potential difference value within the device and compensates for all charges above this potential value, preventing upward tracers from forming in the external moving or static sensor elements.

[0014] The variable radio frequency electromagnetic compensator device, the subject of the present invention, is the result of knowledge of the frequency spectra existing in atmospheric phenomena and in the electromagnetic pulses generated in them and those derived from external sources, such as radiating towers, telecommunications, radars and AM, FM signals, as well as research related to the analysis of variable radio frequency resonant modes in various structures.

[0015] The design of the device that is the subject of the invention has also been based on studies on the results of the radiofrequency electromagnetic field obtained by simulation for distributions of the electric field E, magnetic field H and surface current density J at different times comparable to each other in frequency spectra between 0.4 GHz and 1.9 GHz, where potential designs of resonant structures of electromagnetic fields are concluded that have a main resonant mode at a certain frequency in GHz and a quasi-continuum of oblique modes in the rest of the frequency spectrum, achieving design results of the device that is the subject of the invention, which acts as a radiofrequency electromagnetic resonator that facilitates electrical discharges, mainly in the referred frequency spectrum (0.4 to 1.9 GHz).These electrical discharges occur due to the absorption of variable radiofrequency electromagnetic fields and the recombination of oppositely charged electric charges (mostly electrons and positive ions). This happens through the interaction of static electric and magnetic fields, as well as the resonant electromagnetic field at various frequencies. Both of these actions facilitate the combination of charges, as they become temporarily trapped in nearby areas of confinement by the radiofrequency electromagnetic field, where the mobility promoted by the static fields further enhances the equalization of the electric charge.Therefore, the device of the invention has as its operating principle, on the one hand, acting with high reactance to the passage of high frequency currents, transforming it into heat, allowing only low frequency currents to pass through, and on the other hand, the compensation of the electromagnetic fields of variable radio frequency, acting as a constant sink, from a certain potential difference (on the order of 10-20 KV), of the electric charges of variable radio frequency.

[0016] These processes take place within the confines of the device, which is a sealed and fireproof box, but its permanent and almost continuous activity is felt in a wider environment, specifically in all the conductive structures connected to both terminals of the device, whether directly or by electrical continuity, since the compensatory processes of homogenization, conductivity between materials and thermalization favor diffusion between conductive media in local imbalance environments.

[0017] Based on these studies, and bearing in mind that the device has a limit in its electromagnetic compensation capacity, which basically depends on the transmission speed of the charges accumulated in the mobile or static collectors of the structure to be protected (for example, the blade of a wind turbine) towards the device, as well as the value of the ground resistance to which the device is connected (it must always be less than 10 Ohms for there to be good transmission of electrical charges to the device) and the frequency spectrum of the transmitted current, with the installation of the device a variable absorption of low intensity current to ground is achieved, preventing the external mobile or static collector systems of the structure to be protected in which it is incorporated, from generating upward streamers (derived from their own movement or from possible variations of electric fields of atmospheric origin),Coupling of electromagnetic pulses of varying frequencies radiated from the outside and possible saturations of electrostatic charges in said sensors.

[0018] To this end, and specifically, the device essentially comprises two conductive connection adapters, responsible for connecting the device to the external sensors of the element to be protected, on the one hand, and to the ground, on the other; two elements of high reactance to the passage of high-frequency current and energy absorbers in the form of heat, one of which is responsible for generating a counter-electromotive force to the passage of the initial high-frequency current, lowering the frequency and absorbing part of the energy generated as heat, finally reaching the other element, once the current has passed through a central system formed by a dielectric insulator located between both conductive elements and which basically forms the frequency resonator, this other high-reactance element absorbing the residual energy and only allowing low-frequency current to pass.

[0019] Furthermore, in the preferred embodiment, it also comprises two supports of insulating material, for fixing the aforementioned elements inside a box, and which, in turn, prevent the central system of the dielectric insulator from touching the walls of said box, a very important concept, since electric arcs can form between the conductive elements of said system in its compensation process and normal operation.

[0020] For its part, the central system, composed of the dielectric insulator and the aforementioned two conductive elements arranged on both sides of it, form the electromagnetic resonator and compensator itself.

[0021] Regarding the enclosure, it should preferably be made of insulating material, watertight and airtight, with mechanical and fireproof protection. This is essential to ensure that electrical charges only enter through the conductive connection adapters, which are located externally on opposite sides of the enclosure, and to prevent the entry of electrified air or water, which could alter the resonator's operating conditions or cause a loss of insulation and resistance to the internal heat generated, which must withstand at least 200 Q C.

[0022] The device also includes, incorporated in the box, a series of pressure aeration valves from the inside out and airtight to prevent the entry of moisture and air, responsible for removing the internal overpressure of the box, so that there is always the same pressure inside and outside the box, as well as to extract any moisture that may be inside the box and prevent moisture from entering the box.

[0023] Preferably, the box includes four pressure relief valves, although this number may vary depending on the speed and volume of air to be released, to prevent excessive overpressure inside the box that could rupture it. Typically, there will be a minimum of two valves and a maximum of four.

[0024] Finally, it should be mentioned that the described elements of the device may have various geometric shapes, which will depend on the needs and protection design of the structures to which it is intended.

[0025] In any case, the only premise is that, for the variable radio frequency electromagnetic compensator device to function correctly, it must be taken into account that the conductive elements located on both sides of the dielectric insulator must have a specific separation, depending on the conductivity of the material used and the degree of insulation of said dielectric element.

[0026] DESCRIPTION OF THE DRAWINGS

[0027] To complement the description being made and in order to help a better understanding of the characteristics of the invention, a drawing is attached to this descriptive document as an integral part thereof, in which the following has been represented for illustrative and non-limiting purposes:

[0028] Figure number 1 and only.- Shows a schematic side perspective view of an example of the embodiment of the variable compensation device that is the subject of the invention, showing the main parts and elements that it comprises, as well as its configuration and arrangement.

[0029] PREFERRED EMBODIMENT OF THE INVENTION

[0030] In view of Figure 1, and according to the numbering adopted therein, an example of a non-limiting embodiment of the variable radio frequency electromagnetic compensator device of the invention can be observed, which comprises what is described in detail below. Thus, as can be seen in said figure, the device of the invention, applicable as a protection system against direct lightning strikes on the blades of wind turbines or other mobile or static structures and on mobile and static elements for collecting electrical charges in general, and as a protector against electromagnetic pulses that may affect them from atmospheric discharges between clouds, positive or negative in their immediate vicinity, and from those originating from emissions from radiating towers or antennas, telecommunications, radars of any type, or other sources, comprises at least the following essential elements:

[0031] - two conductive connection adapters (1, 2), a first adapter (1) responsible for the connections of the device with the external sensors of the element to be protected on one side, and a second adapter (2) responsible for the connections with the ground connection, on the other;

[0032] - two high reactance elements to the passage of high frequency current and energy absorbers in the form of heat (3, 4) which, connected to both sides of a frequency resonator (7, 8, 9) and respectively to the two adapters (1, 2), are responsible, a first element (3) connected to the first adapter (1), for generating a counter electromotive force to the passage of the initial high frequency current, lowering the frequency and absorbing part of the energy generated in heat, and a second element (4) connected to the second adapter (2) and, once the current has passed through the frequency resonator (7, 8, 9), for absorbing the residual energy, allowing only low frequency current to pass;and - a frequency resonator that constitutes the electromagnetic compensator itself, being composed of a dielectric insulator (9) located between a first and a second conductive elements (7, 8) which, in turn, connect respectively to the aforementioned first and second elements of high reactance to the passage of high frequency current and energy absorbers in the form of heat (3, 4).;

[0033] Furthermore, preferably, said elements (1, 2, 3, 4, 7, 8 and 9) are incorporated into a watertight box (10), so that all of them are housed and isolated inside except for the adapters (1, 2) which are located externally on opposite sides of it.

[0034] Inside the box (10) there are two supports (5) made of insulating material, to fix the internal elements of the box and prevent the frequency resonator (7, 8, 9) from touching the walls of said box (10) and causing electrical arcs to form during its operation.

[0035] Preferably, the box (10) is made of insulating material, watertight and airtight, with mechanical and fireproof protection, capable of withstanding temperatures up to 200 Q C.

[0036] Furthermore, preferably, the box (10) incorporates pressure relief valves (6) that are airtight and moisture- and airtight, designed to release internal overpressure so that the pressure inside and outside the box is always the same, as well as to extract any moisture present inside the box and prevent moisture from entering. Preferably, the box has four pressure relief valves (6), and at least two (6) valves.

[0037] Having sufficiently described the nature of the present invention, as well as the manner of putting it into practice, it is not considered necessary to make its explanation more extensive so that any expert in the field can understand its scope and the advantages that derive from it.