Electric field mill for detecting an electric field of a conductor, and method for detecting an electric field

Abstract

The invention relates to an electric field mill (10) for detecting an electric field (E) of a conductor (12), comprising at least one sensor element (14), the sensor element (14) having at least one field amplification element (24). The invention also relates to a method for determining an electric field (E).

Description

[0001] Description

[0002] Electric field mill for detecting an electric field of a conductor and method for detecting an electric field

[0003] The invention relates to an electric field mill for detecting an electric field of a conductor, having at least one sensor element according to the applicable patent claim 1. Furthermore, the invention relates to a method for determining an electric field strength of an electric field of a conductor by means of an electric field mill.

[0004] In an electric field mill, charge carriers are displaced against an external electric field by alternately shielding two electrode surfaces, particularly so-called sensor surfaces. By measuring the displacement current, the electric field strength of the external electric field can be determined. In a macroscopic field mill design, the surfaces of the electrodes are orders of magnitude larger than the surfaces of the leads between the electrodes and the measuring circuit. Interference signals such as crosstalk from the field mill drive or coupling of the external field via surfaces that are not completely shielded by the aforementioned shield are therefore not significantly significant.

[0005] The functional principle is implemented in particular as a so-called MEMS voltmeter with microelectromechanical components. In such a microelectromechanical field mill, however, the surfaces of the electrodes and the circuitry are of a similar magnitude, which is why shielding is essential. At the same time, almost any type of attenuation of interference signals, particularly by shielding or increasing the distance to the measurement object, also weakens the field actually being measured and its effect on the sensor surfaces of the field mill. The actual measurement signal therefore becomes weaker. The sensor surfaces of the microelectromechanical field mill are significantly smaller than those of a macroscopic field mill.

[0006] The electromechanical field mill offers only a small surface area for capturing the electric field and therefore exhibits only low sensitivity. Sensitivity can be increased by using high shutter frequencies.

[0007] However, if one is interested not only in the field strength, but especially in the voltage of the object generating the field, the signal, particularly the signal equivalent to the field strength, decreases with distance. It is therefore practical to keep the distance as small as possible.

[0008] The object of the present invention is to provide an electric field mill and a method by means of which an electric field or a voltage of a conductor can be determined.

[0009] This object is achieved by an electric field mill and by a method according to the independent patent claims. Advantageous embodiments are specified in the subclaims.

[0010] One aspect of the invention relates to an electric field mill for detecting an electric field of a conductor, with at least one sensor element.

[0011] It is provided that the sensor element has at least one field amplification element.

[0012] In particular, it is therefore provided that the detected field is amplified within the sensor element and can therefore then be detected accordingly, for example via the sensor surfaces. The electric field can thus be determined in an improved manner, and subsequently, for example, the voltage can be determined on the basis of a distance to the electrical conductor and the electric field. In particular, since the electric field mill, which is designed in particular as a MEMS field mill, for example with its sensor surfaces, cannot be brought as close as desired to the object with the voltage to be determined for technical and / or practical reasons, the invention is advantageous. For example, for safety reasons due to high voltages or simply because other components are in the way and the combination of MEMS and circuit carrier cannot be brought any closer.

[0013] According to the invention, the electric field is amplified specifically in the area of ​​the MEMS component by means of a passive component. The functional principle is particularly analogous to the operation of capacitors with a dielectric or other insulating material. The material insulates, but amplifies the capacitance of the capacitor by a factor of a relative permittivity s r of the insulating material. This factor is directly, and in particular proportionally, taken into account. With the MEMS field mill, an increase in capacitance means an increase in the field density of the electric field emanating from the measurement object in the area of ​​the MEMS component and its sensor surfaces. This allows the measurement signal to be amplified without bringing the entire component closer to the measurement object, especially the conductor.

[0014] In particular, the essential difference to the state of the art is that the sensor surfaces of the sensor element are not brought closer to the conductor, but rather an additional substance is introduced which amplifies the electric field accordingly.

[0015] According to an advantageous embodiment, the field amplification element is designed as a dielectric. In particular, the dielectric has a corresponding permittivity s r Based on the dielectric, the electric field can be reliably amplified. This allows for improved operation of the electric field mill.

[0016] A further advantageous embodiment provides that the field amplification element is formed on an outer side of the sensor element, which faces the conductor. In particular, the field amplification element is thus arranged between the conductor and the sensor element in a corresponding arrangement with the conductor. The field amplification element is thus formed in or on a measuring area of ​​the electric field mill. Thus, the electric field from the conductor to the sensor element can be amplified accordingly.

[0017] In a further advantageous embodiment, the field amplification element is formed on a shutter device of the sensor element. For example, the shutter can have two corresponding shutter surfaces. In particular, the field amplification element can then be arranged, for example, between the shutter surfaces, for example also in a movable manner. This makes it possible for the amplification element to be reliably provided within the sensor element.

[0018] It is also advantageous if the field amplification element is formed between at least one sensor surface of the sensor element and a shutter device of the sensor element. In particular, the field amplification element is thus formed between the sensor surface and the shutter device. In particular, field amplification can thus be realized between the shutter device and the sensor surface. Corresponding installation spaces within the field mill can therefore be used in order to be able to reliably amplify the electric field. Corresponding installation spaces are thus advantageously utilized. A further advantageous embodiment provides that the electric field mill has an electronic computing device, wherein a relative permittivity of the field amplification element is taken into account when determining the electric field by means of the electronic computing device.In particular, the relative permittivity, for example, can be stored within the electronic computing device. This allows the electric field to be reliably amplified and then, based on this factor, taken into account again to reliably determine the actual electric field and thus the actual voltage across the conductor.

[0019] It is also advantageous if the electric field mill has an electronic computing device, wherein, when determining the electric field by means of the electronic computing device, a distance between the field amplification element and a sensor surface of the sensor element is taken into account. In particular, the distance between the field amplification element, which can also be referred to as a field concentrator, and the corresponding sensor surfaces can thus be taken into account. This allows for an improved determination of the actual electric field and the voltage in the conductor.

[0020] A further advantageous embodiment provides that the electric field mill has an electronic computing device, wherein a distance between the field reinforcement element and the conductor is taken into account when determining the electric field by means of the electronic computing device. In particular, if, for example, the field reinforcement element is not located directly on the conductor, the distance can also be taken into account accordingly. On the basis of the distance, a reliable conclusion can then be drawn about the electric field, or by means of the distance, the voltage can be deduced from the electric field. The voltage within the conductor can thus be reliably determined, in particular without contact.

[0021] In a further advantageous embodiment, the field amplification element is substantially cylindrical. In particular, the field amplification element can thus be designed as a kind of extension of the sensor surfaces and can be brought to the conductor accordingly. Thus, a simple field amplification element can be provided.

[0022] Furthermore, it has proven advantageous if the field amplification element is essentially conical. In particular, a type of funnel can be created. In particular, a larger portion of the electric field can be "captured" at the conductor and directed conically toward the sensor element or the sensor surface. This allows the electric field to be detected even more precisely.

[0023] In this case, an advantageous embodiment provides that the field amplification element is arranged with a pointed side of the cone in the direction of a sensor surface of the sensor element. The cone is flattened in particular at the point at which it meets the sensor surfaces and has in particular the size of the sensor surface. With the larger side of the cone, the field amplification element is thus designed in particular in the direction of the conductor. The electric field can thus be detected reliably. In particular, the surface of the field amplification element can thus be enlarged towards the measurement object and taper towards the sensor surfaces.

[0024] It has also proven advantageous if the field amplification element is arranged with a pointed side of the cone facing a sensor surface of the sensor element. This allows the electric field to be detected with corresponding reliability. In particular, the area of ​​the field amplification element can be enlarged toward the measurement object and taper towards the sensor surfaces.

[0025] A further advantageous embodiment provides that the field amplification element is designed to be electrically insulating. In particular, the field amplification element is designed to be at least electrically insulating with respect to the sensor surfaces. This prevents corresponding interference on the sensor surfaces.

[0026] In a further advantageous embodiment, the field amplification element is designed as an electrical conductor. Thus, a field amplification element can be provided in a simple manner.

[0027] It can further be provided that the field amplification element is floatingly insulated from the sensor surface of the sensor element. In particular, the sensor element and the field amplification element are thus electrically insulated from one another. It can further be provided that the field amplification element is designed to be high-resistance and coupled to an electrical ground of the sensor element, so that no potential can develop on the conductor.

[0028] A further aspect of the invention relates to a method for determining an electric field of a conductor by means of an electric field mill according to the preceding aspect. The electric field is amplified by means of the field amplification element. The amplified field is detected by means of at least one sensor surface of the sensor element. The electric field is determined on the basis of the amplified field, taking into account a relative permittivity of the field amplification element, by means of an electronic computing device of the electric field mill.

[0029] This can be, at least in part, a computer-implemented method, which can be carried out in particular by means of the electronic computing device. For this purpose, the electronic computing device has, for example, a computer program product with program code means which, when the program code means are processed by the electronic computing device, cause the electronic computing device to carry out a method accordingly. Therefore, a further aspect of the invention also relates to a computer-readable storage medium with the corresponding computer program product.

[0030] Advantageous embodiments of the electric field mill are to be regarded as advantageous embodiments of the method, the computer program product, the computer-readable storage medium and also the electronic computing device.

[0031] A computing unit / electronic computing device can be understood, in particular, as a data processing device containing a processing circuit. The computing unit can therefore, in particular, process data to perform computing operations. This may also include operations for performing indexed access to a data structure, for example, a look-up table (LUT).

[0032] The computing unit can in particular contain one or more computers, one or more microcontrollers and / or one or more integrated circuits, for example one or more application-specific integrated circuits (AS ICs), one or more field-programmable gate arrays (FPGAs), and / or one or more single-chip systems (SoCs). The computing unit can also contain one or more processors, for example one or more microprocessors, one or more central processing units (CPUs), one or more graphics processing units (GPUs) and / or one or more signal processors, in particular one or more digital signal processors (DSPs).The computing unit may also include a physical or virtual network of computers or other of the aforementioned units.

[0033] In various embodiments, the computing unit includes one or more hardware and / or software interfaces and / or one or more memory units.

[0034] A memory unit can be a volatile data memory, for example a dynamic random access memory (DRAM) or a static random access memory (SRAM), or a non-volatile data memory, for example a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), a flash memory or flash EEPROM, a ferroelectric random access memory (FRAM), a magnetoresistive random access memory,MRAM (magnetoresistive random access memory) or phase-change random access memory, PCRAM (phase-change random access memory).

[0035] For use cases or application situations that may arise during the method and are not explicitly described here, it may be provided that, according to the method, an error message and / or a request for user feedback is issued and / or a default setting and / or a predetermined initial state is set. Regardless of the grammatical gender of a particular term, this includes persons with male, female, or other gender identities.

[0036] Further features and combinations of features of the invention emerge from the figures and their description, as well as from the claims. In particular, further embodiments of the invention do not necessarily have to contain all features of one of the claims. Further embodiments of the invention may have features or combinations of features that are not mentioned in the claims.

[0037] Showing:

[0038] FIG 1 is a schematic block diagram according to an embodiment of an electric field mill;

[0039] FIG 2 is a schematic side view of an embodiment of an electric field mill; and

[0040] FIG 3 shows a further schematic side view of an embodiment of an electric field mill.

[0041] The invention is explained in more detail below with reference to specific exemplary embodiments and associated schematic drawings. In the figures, identical or functionally equivalent elements may be provided with the same reference numerals. The description of identical or functionally equivalent elements may not necessarily be repeated for different figures.

[0042] FIG 1 shows a schematic block diagram of an embodiment of an electric field mill 10. The electric field mill 10 is designed to determine an electric field E of a conductor 12. In particular, a contactless determination of a voltage in the conductor 12 is made possible via the electric field mill 10. For this purpose, the electric field mill 10 has a sensor element 14. In the following exemplary embodiment, the sensor element 14 has a first sensor surface 16 and a second sensor surface 18. Furthermore, in particular, a shutter device 20 is shown, which performs a movement 22.

[0043] The movement 22 can in particular be sinusoidal.

[0044] FIG 1 further shows that the sensor element 14 can have at least one field amplification element 24.

[0045] In the following exemplary embodiment, a field amplification element 24 is formed on the shutter device 20 and a further field amplification element 24 between the shutter device 20 and the sensor surfaces 16, 18.

[0046] FIG 1 further shows that the first sensor surface 16 and the second sensor surface 18 are coupled to an electronic computing device 26 of the electric field mill 10. For this purpose, the electronic computing device 26 can, for example, have a first I / U converter 28, which is coupled in particular to the first sensor surface 16. Furthermore, the electronic computing device 26 has a second I / U converter 30, which is in contact in particular with the second sensor surface 28. The two I / U converters 28, 30 are added accordingly in an addition element 32 and fed to an analog signal converter 34.

[0047] FIG. 2 shows a schematic side view of an embodiment of an electric field mill 10. In the following embodiment, the field amplification element 24 is formed between the conductor 12 and the sensor surfaces 16, 18. Furthermore, the shutter device 20 can be formed, for example, in the component with the sensor surfaces 16, 18.

[0048] The field amplification element 24 can be designed, in particular, as a dielectric. Furthermore, FIG. 2 shows that the field amplification element 24 is formed on an outer side of the sensor element 14, which faces the conductor 12.

[0049] FIG 2 further shows that, for example, the electronic computing device 26 is formed on the basis of a printed circuit board 36 and further electronic components 38. The sensor element 14 can be formed directly on the printed circuit board 26. In the present exemplary embodiment, a distance 40 is formed in particular between at least the sensor surfaces 16, 18 and the field amplification element 24. This distance 40 can be taken into account accordingly by the electronic computing device 26. Furthermore, when determining the electric field E by means of the electronic computing device 26, a relative permittivity of the field amplification element 24 can be taken into account. Furthermore, it can be provided that when determining the electric field E by means of the electronic computing device 26, a distance 42 between the field amplification element 24 and the conductor 12 can also be taken into account.

[0050] FIG 2 further shows that the field reinforcement element 24 is essentially cylindrical.

[0051] In particular, it is thus provided that, for example, the electric field mill 10 with the sensor surfaces 16, 18 cannot be brought arbitrarily close to the conductor 12 with the voltage to be determined for technical and / or practical reasons. For example, for safety reasons due to high voltages or simply because other components are in the way and the assembly of the sensor surfaces 16, 18 and, for example, the circuit board 36 cannot be brought closer.

[0052] In particular, it is now provided that the electric field E is amplified specifically in the area of ​​the sensor element 14 by means of a passive component. This can be, for example, a dielectric. The functional principle is analogous to the operation of capacitors with dielectric or other insulating materials. The material insulates, thereby amplifying the capacitance of the capacitor by the factor of the relative permittivity s r of the insulating material. The factor is directly proportional. Applied to the electric field mill 10, an increase in capacitance means an increase in the field density of the electric field E emanating from the conductor 12 in the region of the sensor element 14 and the corresponding sensor surfaces 16, 18. Thus, the measurement signal can be amplified without bringing the entire component closer to the conductor 12. Such an arrangement is shown in FIG. 2.

[0053] FIG. 3 shows a further schematic side view of an embodiment of an electric field mill 10. In the following exemplary embodiment, it is shown in particular that the field amplification element 24 is essentially conical. In particular, it is shown that the field amplification element 24 is arranged with a pointed side 44 of the cone in the direction of the sensor surface 16, 18 of the sensor element 14.

[0054] Furthermore, it can be provided, in particular, that the field amplification element 24 is electrically insulating. FIG. 3 further shows that the field amplification element 24 can also be in direct contact with the sensor surfaces 16, 18 or the shutter device 20.

[0055] In particular, it can be provided that in addition to the relative permittivity s rother influencing factors must also be taken into account. In particular, the distance 42 between the field amplification element 24 and the conductor 12 and the distance 40 between the field amplification element 24 and the sensor surfaces 16, 18 can be taken into account. It is particularly advantageous if the sensor element 14 or the sensor surfaces 16, 18 are closed by means of the field amplification element 24, in particular as shown in FIG 3, so that the internal moving components are protected against dust particles and the like. It is also advantageous if the surface of the field amplification element 24 increases towards the conductor 12 and tapers to a point towards the mirror surfaces 16, 18.

[0056] This is also important in the context of the above-mentioned shielding of the other electronics from the conductor 12. The use of such a field amplification element 24, which is fitted appropriately onto the measuring part or onto the conductor 12, only significantly amplifies this in the area of ​​the sensor surfaces 16, 18. However, not in the area of ​​the printed circuit board 36 and thus the other circuitry, in addition to that underneath the component of the sensor surfaces 16, 18. Although these influences are possible, they can be reduced or optimized by further optimization of the geometry of the field amplification element 24. If the component itself were to be brought closer to the conductor 12, the measurement and interference signals would be amplified equally.

[0057] Instead of an insulator with the highest possible relative permittivity, the principle also works with an electrical conductor, in particular metal, which is connected in a floating manner and is electrically insulated from the sensor surfaces 16, 18.

[0058] Reference symbol list

[0059] 10 electric field mill

[0060] 12 ladders

[0061] 14 Sensor element

[0062] 16 first sensor area

[0063] 18 second sensor surface

[0064] 20 Shutt er facility

[0065] 22 Movement

[0066] 24 Field reinforcement element

[0067] 26 electronic computing device

[0068] 28 first I / U converter

[0069] 30 second I / U converter

[0070] 32 addition element

[0071] 34 analog signal converters

[0072] 36 circuit board

[0073] 38 electronic component

[0074] 40 distance

[0075] 42 distance

[0076] 44 pointed side

[0077] E electric field

Claims

Patent claims 1. Electric field mill (10) for detecting an electric field (E) of a conductor (12), with at least one sensor element (14), characterized in that the sensor element (14) has at least one field amplification element (24).

2. Electric field mill (10) according to claim 1, characterized in that the field amplifying element (24) is designed as a dielectric.

3. Electric field mill (10) according to claim 1 or 2, characterized in that the field amplification element (24) is formed on an outer side of the sensor element (14) which faces the conductor (12).

4. Electric field mill (10) according to one of the preceding claims, characterized in that the field amplification element (24) is formed on a shutter device (20) of the sensor element (14).

5. Electric field mill (10) according to one of the preceding claims, characterized in that the field amplification element (24) is formed between at least one sensor surface (16, 18) of the sensor element (14) and on a shutter device (20) of the sensor element (14).

6. Electric field mill (10) according to one of the preceding claims, characterized in that the electric field mill (10) has an electronic computing device (26), wherein when determining the electric field (E) by means of the electronic computing device (26) a relative permittivity of the field amplification element (24) is taken into account.

7. Electric field mill (10) according to one of the preceding claims, characterized in that the electric field mill (10) has an electronic computing device (26), wherein when determining the electric field (E) by means of the electronic computing device (26), a distance (40) between the field amplification element (24) and a sensor surface (16, 18) of the sensor element (14) is taken into account.

8. Electric field mill (10) according to one of the preceding claims, characterized in that the electric field mill (10) has an electronic computing device (26), wherein a distance (42) between the field amplification element (24) and the conductor (12) is taken into account when determining the electric field (E) by means of the electronic computing device (26).

9. Electric field mill (10) according to one of the preceding claims, characterized in that the field reinforcement element (24) is substantially cylindrical.

10. Electric field mill (10) according to one of claims 1 to 8, characterized in that the field reinforcement element (24) is substantially conical.

11. Electric field mill (10) according to claim 10, characterized in that the field amplification element (24) is arranged with a pointed side (44) of the cone in the direction of a sensor surface (16, 18) of the sensor element (14).

12. Electric field mill (10) according to one of the preceding claims, characterized in that the field amplification element (24) is electrically insulating.

13. Electric field mill (10) according to one of the preceding claims, characterized in that the field reinforcement element (24) is designed as an electrical conductor.

14. Electric field mill (10) according to claim 13, characterized in that the field amplification element (24) is floatingly insulated from the sensor surface (16, 18) of the sensor element (14).

15. A method for determining an electric field (E) of a conductor (12) by means of an electric field mill (10) according to one of claims 1 to 14, comprising the steps: - amplifying the electric field (E) by means of the field amplifying element (24); - detecting the amplified field by means of at least one sensor surface (16, 18) of the sensor element (14); - Determining the electric field (E) on the basis of the amplified field, taking into account a relative permittivity of the field amplification element (24) by means of an electronic computing device (26) of the electric field mill (10).

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