Hybrid electric propulsion device

Abstract

The application discloses a hybrid electric propulsion device, comprising: an insulating support, a plurality of needle-tube electrode modules and a plurality of wire-tube electrode modules, the needle-tube electrode modules and the wire-tube electrode modules are fixed alternately on the insulating support to form an array structure, each wire-tube electrode module is connected to a ground end in parallel, and each needle-tube electrode module is connected to a high-voltage end in parallel; the wire-tube electrode module comprises a plurality of wire-tube electrode rods fixed on a conductive support, the wire-tube electrode rod comprises a first metal tube and a metal wire, the metal wire is connected to the conductive support and kept in the same horizontal plane with the first metal tube; the larger physical size of the metal wire of the ground end is used to weaken the electric field in the direction of the positive space charge movement, to inhibit the development of the streamer to the deep gap, thereby significantly improving the breakdown voltage threshold, and through the combination of the high ionization capacity of the tungsten needle and the electric field uniformity of the wire / tube, the thrust density and the system stability are improved together.

Description

Technical Field

[0001] This invention relates to the field of electric propulsion technology, and more specifically to a hybrid electric propulsion device. Background Technology

[0002] Electro-hydro Dynamics (EHD) thrusters based on the Biefeld-Brown effect have broad application prospects in near-space vehicles and micro / nano satellites due to their quiet operation, lack of moving parts, and absence of propellant requirements.

[0003] Existing EHD thrusters typically employ asymmetric capacitor structures (such as needle-tube structures) to generate ion wind thrust, which presents the following bottlenecks in practical applications:

[0004] (1) Performance limitations due to simple structure: Traditional needle-tube structures generate relatively small thrust and have low thrust density, which is difficult to meet the power requirements of large aircraft; while existing devices usually repeatedly stack electrodes of a single shape (such as all-needle or all-tube type), such as the electric propulsion device proposed in the patent application document with publication number CN119933967A. Although the needle-tube structure has good stability and simple assembly, the integrated structure is prone to grounding of the emitter, and the breakdown voltage between the plates is limited.

[0005] (2) Polarity effect limitation: In an integrated emitter-receiver propulsion device, when the polarity of the electrode voltage is changed (either the emitter or the receiver is connected to a high voltage), the breakdown voltage is significantly different due to the difference in the electric field of the direction of space charge movement. In particular, when the transmitter is connected to a negative high voltage, the movement of positive space charges strengthens the electric field, which is conducive to the development of the streamer, resulting in a low breakdown voltage and limiting the improvement of the thrust-to-power ratio. Moreover, the finer the needle electrode, the stronger the electric field and the lower the breakdown voltage.

[0006] In related technologies, patent application CN121024880A proposes an electrode-shared series structure. The electrodes mainly consist of a conductive support structure and an ionization needle tip. Positive and negative high voltages (positive → negative → positive → negative) are alternately supplied to each ion wind generating unit via a power source, allowing the same electrode to sequentially act as both an ionizing electrode and a receiving electrode at different stages, achieving cascaded continuous acceleration of ions. This scheme focuses on reducing the number of parts, lightening the weight, and extending the acceleration path by reusing electrodes; its essence remains a propulsion device formed by repeatedly stacking electrodes of a single shape. Patent application CN117889057A proposes a sawtooth electrode propulsion device using electrode plates with a flat front end and a sawtooth rear end. The propulsion unit is formed by the alternating arrangement of these plates. The sawtooth rear end releases negative charges to neutralize positive ions, aiming to reduce charged ion backflow and improve ion neutralization capacity. The master's thesis, "Influencing Factors of Thrust and Thrust-to-Power Ratio of Ion Wind Aircraft and Propulsion Tests," mainly studies wire-airfoil electrode arrays, focusing on optimizing the geometric parameters of a single structure (wire-airfoil) (such as airfoil chord length, wire diameter, and matrix arrangement) to improve the thrust-to-power ratio.

[0007] Therefore, existing technologies generally increase thrust by increasing the number of similar electrodes (such as stacking more layers of needles). Summary of the Invention

[0008] The technical problem to be solved by the present invention is how to provide a hybrid electric propulsion device that can ensure aerodynamic shape while maximizing thrust density and breakdown voltage.

[0009] The present invention solves the above-mentioned technical problems through the following technical means: A hybrid electric propulsion device is proposed, comprising an insulating support, several needle-tube electrode modules and several wire-tube electrode modules. The needle-tube electrode modules and wire-tube electrode modules are alternately fixed to the insulating support to form an array structure. Each of the wire-tube electrode modules is connected in parallel to the grounding terminal, and each of the needle-tube electrode modules is connected in parallel to the high-voltage terminal. The wire-tube electrode module includes several wire-tube electrode rods fixed to a conductive support. Each wire-tube electrode rod includes a first metal tube and a metal wire. The metal wire is connected to the conductive support and is kept on the same horizontal plane as the first metal tube.

[0010] Furthermore, the needle-tube electrode module includes several needle-tube electrode rods fixed to a conductive support. Each needle-tube electrode rod includes a second metal tube and a tungsten needle. Several mounting holes are formed on the second metal tube, and tungsten needles are embedded in the mounting holes. The tungsten needles on each needle-tube electrode rod point in the same direction.

[0011] Furthermore, several adjustment holes are evenly spaced on the insulating support and the conductive support. The conductive support is fixed to the adjustment holes on the insulating support by an insulating nut so that the distance between the needle-tube electrode module and the wire-tube electrode module is adjustable. The metal tubes are fixed to the conductive bracket by conductive bolts through adjustment holes so that the spacing between the metal tubes can be adjusted.

[0012] Furthermore, the number of second metal tubes in the needle-tube electrode module is the same as the number of first metal tubes in the wire-tube electrode module, and their positions correspond. The tungsten needle embedded in the second metal tube in the needle-tube electrode module points to the back of the first metal tube at the corresponding position in the previous wire-tube electrode module, and the front of the first metal tube is provided with a metal wire.

[0013] Furthermore, the metal tube is made of a conductive metal round bar, and the inside of the metal tube is hollow with internal threads at both ends.

[0014] Furthermore, the metal wire is connected to the conductive support by fixing bolts, and the metal wire is taut and located directly above the metal tube.

[0015] Furthermore, the base of the tungsten needle is connected to the mounting hole on the second metal tube by a threaded connection so that the tungsten needle can be embedded in the mounting hole, and the tips of each tungsten needle are kept on a horizontal plane after being embedded.

[0016] The advantages of this invention are: This invention forms a hybrid electric propulsion device by alternately fixing several needle-tube electrode modules and several wire-tube electrode modules to an insulating support, in which the needle-tube electrode modules are connected in parallel to the high-voltage end and the wire-tube electrode modules are connected in parallel to the ground end. The needle-tube electrode structure is connected to high voltage, utilizing the excellent ionization effect of tungsten needles to generate ions; simultaneously, the wire-tube electrode structure is grounded. Because the physical dimensions of the metal wires in the wire-tube electrode modules are larger than those of the tungsten needles, the electric field strength on their surfaces is relatively weaker. This weakens the enhancing effect of positive space charge on the electric field at the ground end, making the strengthening effect of positive space charge movement on the electric field less significant. The breakdown voltage is higher compared to the needle-tube electrode structure. The needle-tube electrode structure has a better ionization effect when connected to high voltage, generating greater thrust, and weakens the electric field in the direction of positive space charge movement, which is not conducive to the streamer's development into the depth of the gap, hence the high breakdown voltage. This hybrid electric propulsion device combines the advantages of the high ionization capability of tungsten needle electrodes with the advantages of the wire-tube electrode structure in terms of electric field distribution uniformity and structural stability. This hybrid design maximizes the overall thrust density while ensuring the aerodynamic shape, and can achieve a joint improvement in thrust density and system stability.

[0017] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0018] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0019] Figure 1 This is a schematic diagram of a hybrid electric propulsion device proposed in one embodiment of the present invention; Figure 2 This is a schematic diagram of the structure of a wire-tube electrode module in one embodiment of the present invention; Figure 3 This is a partially enlarged schematic diagram of a wire-tube electrode module in one embodiment of the present invention; Figure 4 This is a schematic diagram of the needle-tube electrode module in one embodiment of the present invention; Figure 5 This is a schematic diagram illustrating the relationship between emitter grounding and high-voltage breakdown voltage and thrust in one embodiment of the present invention.

[0020] In the picture: 1-Hybrid electric propulsion device; 2-Wire-tube electrode module; 3-Needle-tube electrode module; 4-Insulating bracket; 5-Insulating nut; 6-Metal wire; 7-Conductive bracket; 8-Fixing bolt; 9-Conductive screw; 10-First metal tube; 11-Second metal tube; 12-Tungsten needle. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] like Figures 1 to 4 As shown, the first embodiment of the present invention proposes a hybrid electric propulsion device. The hybrid electric propulsion device 1 includes an insulating support 4, a plurality of needle-tube electrode modules 3 and a plurality of wire-tube electrode modules 2. The needle-tube electrode modules 3 and the wire-tube electrode modules 2 are alternately fixed to the vertical insulating support 4 to form an array structure. Each of the wire-tube electrode modules 2 is connected in parallel to the grounding terminal, and each of the needle-tube electrode modules 3 is connected in parallel to the high voltage terminal. The wire-tube electrode module 2 includes several wire-tube electrode rods fixed to the conductive support 7. Each wire-tube electrode rod includes a first metal tube 10 and a metal wire 6. The metal wire 6 is connected to the conductive support 7 and is kept on the same horizontal plane as the first metal tube 10.

[0023] It should be noted that in this embodiment, the needle-tube electrode module and the wire-tube electrode module are alternately fixed on a vertical insulating support. Each wire-tube electrode module is connected in parallel to the grounding terminal, and each needle-tube electrode module is connected in parallel to the high-voltage terminal. The array structure formed is composed of multiple levels of electrode modules connected in parallel. Through the hybrid configuration of "needle-tube connected to high voltage and wire-tube grounded", the bottleneck of low breakdown voltage caused by the emitter being connected to negative high voltage in the traditional single structure is overcome. The reason is as follows: In traditional single-structure applications, if the emitter is connected to a negative high voltage, the movement of positive space charges strengthens the electric field, leading to easy streamer development and premature breakdown of air insulation. This embodiment employs a needle-tube electrode structure connected to a high voltage, utilizing the excellent ionization effect of tungsten needles to generate ions. Simultaneously, a wire-tube electrode structure is grounded. Since the physical dimensions of the metal wire in the wire-tube module are larger than those of the tungsten needle, the electric field strength on its surface is relatively weak. This configuration weakens the electric field enhancement effect in the direction of positive space charge movement, hindering the development of discharge current deep into the electrode gap. Therefore, the hybrid electric propulsion device proposed in this embodiment can withstand higher operating voltages before breakdown. This embodiment, on the one hand, suppresses streamer development and improves withstand voltage; on the other hand, since thrust is proportional to the square of the operating voltage, a higher breakdown voltage threshold allows the hybrid electric propulsion device to operate at higher voltages, thereby significantly improving the thrust-to-power ratio and total thrust density, maximizing thrust, and overcoming the low thrust deficiency of existing technologies.

[0024] Therefore, this embodiment utilizes the difference in field strength between the needle and the wire to optimize the ionization region and the migration region, thus solving the problem of electrical breakdown under high voltage conditions. Furthermore, by combining the high ionization capability of the tungsten needle with the electric field uniformity of the wire-tube electrode, it achieves a combined improvement in thrust density and system stability.

[0025] As a further preferred technical solution, the needle-tube electrode module 3 includes a plurality of needle-tube electrode rods fixed to the conductive support 7. Each needle-tube electrode rod includes a second metal tube 11 and a tungsten needle 12. A plurality of mounting holes are opened on the second metal tube 11, and the tungsten needles 12 are embedded in the mounting holes. The tungsten needles 12 on each needle-tube electrode rod point in the same direction.

[0026] Specifically, such as Figures 2 to 3 As shown, the wire-tube electrode module 2 includes a metal wire 6, a first metal tube 10, a horizontal conductive support 7, a fixing bolt 8, and a conductive screw 9. The first metal tube 10 is assembled onto the horizontal conductive support 7 by the fixing bolt 8 and the conductive screw 9. A metal wire 6 is arranged directly above each first metal tube 10. The metal wire 6 is connected to the conductive support 7 by the fixing bolt 8 and is kept in a taut state. After the wire-tube electrode is assembled, the metal wire 6 and the first metal tube 10 are kept on the same horizontal plane.

[0027] like Figure 4As shown, the needle-tube electrode module 3 includes a second metal tube 11, a horizontal conductive support 7, and a tungsten needle 12. The second metal tube 12 is assembled onto the conductive support 7 by fixing bolts 8 and conductive screws 9. Several mounting holes are opened on the second metal tube 11, and the tungsten needle 12 is embedded in the mounting holes. The base of the tungsten needle 12 is connected to the second metal tube 11 by a thread. The tungsten needles embedded in the needle-tube electrode module 3 are all at the same height. After being embedded, the tips of the tungsten needles are kept on a horizontal plane, and the tungsten needles 12 point in the same direction.

[0028] Furthermore, the number of second metal tubes 11 provided in the needle-tube electrode module 3 is the same as the number of first metal tubes 10 provided in the wire-tube electrode module 2, and their positions correspond.

[0029] When assembling the hybrid electric propulsion device, the conductive support 7 in the wire-tube electrode module 2 and the needle-tube electrode module 3 is fixed to the insulating support 4 by the insulating nut 5, forming a structure in which the wire-tube electrode module 2 and the needle-tube electrode module 3 are stacked alternately. The tungsten needle 12 embedded in the second metal tube 11 in the needle-tube electrode module 3 points to the back of the first metal tube 10 at the corresponding position in the previous wire-tube electrode module 2. The front of the first metal tube 10 is provided with a metal wire 6.

[0030] As a further preferred technical solution, the horizontal conductive support 7 has several equally spaced adjustment holes to facilitate the adjustment of the assembly density of the first metal tube 10 and the second metal tube 11. Different assembly densities result in different breakdown voltages and different thrusts.

[0031] The vertical insulating bracket 4 has several equally spaced adjustment holes to facilitate the installation and spacing adjustment of the wire-tube electrode module 2 and the needle-tube electrode module 3. Different spacing devices have different breakdown voltages and generate different thrusts. The vertical insulating bracket 4 is made of high insulation material, which increases the withstand voltage level between the insulation of each vertical electrode.

[0032] It should be noted that both the insulating support 4 and the conductive support 7 have equally spaced adjustment holes, allowing for flexible adjustment of the vertical spacing between electrode modules and the lateral assembly density of each electrode rod within the electrode module according to voltage level and thrust requirements. Specifically, the insulating support 4 has several equally spaced holes, allowing users to adjust the vertical spacing between the wire-tube electrode module and the needle-tube electrode module according to actual needs. Since different spacings correspond to different breakdown voltages and thrust characteristics, this allows the device to flexibly adapt to different voltage levels and thrust requirements. The conductive support 7 also has several equally spaced holes, facilitating the adjustment of the metal tube assembly density. By changing the electrode arrangement density, the thrust output and electrical characteristics of the device can be further fine-tuned, enhancing the device's versatility and experimental flexibility.

[0033] As a further preferred technical solution, both the first metal tube 10 and the second metal tube 11 are made of conductive metal round bars. The metal tubes are hollow inside and have internal threads at both ends, so that they can be assembled onto the transverse conductive bracket 7 by means of conductive screws 9 and insulating nuts 5.

[0034] This device uses a hollow metal tube as its main structural component, threaded at both ends, and connected to a support frame via conductive screws and insulating nuts. The metal tube structure offers high rigidity, and the tungsten needles utilize embedded threaded connections, ensuring all discharge tips are on the same horizontal plane, thus improving discharge consistency and device operational stability. Furthermore, the hollow metal tube serves as the main receiver electrode, secured with conductive screws; the emitter employs embedded threaded discharge tungsten needles, achieving a highly stable electrode encapsulation.

[0035] It should be noted that while traditional single needle-tube electrode stacking provides strong ionization, it is highly susceptible to electrical breakdown (streamer discharge) under the high voltages required by large aircraft. This embodiment integrates needle-tube and wire-tube electrode modules, introducing the wire-tube electrode module as a field strength buffer. Utilizing the larger physical size of the metal wire compared to the tungsten needle tip, it effectively reduces the excessive enhancement of the electric field strength by space charge at the grounding end, thereby significantly improving the overall breakdown voltage threshold. By sacrificing some local ionization strength for overall voltage stability, a better thrust-voltage curve can be obtained through heterogeneous electrode hybridization, such as... Figure 5 As shown: When the needle electrode is connected to ground, the breakdown voltage and thrust are significantly increased. When the wire-tube electrode structure is grounded, the physical size of the wire intersects the needle, and the effect of the positive space charge movement strengthening the electric field is not obvious. The breakdown voltage is larger than that of the needle-tube electrode. The needle-tube electrode structure has a better ionization effect when connected to high voltage, generates greater thrust, and weakens the electric field in the direction of positive space charge movement, which is not conducive to the development of the streamer into the depth of the gap. Therefore, the breakdown voltage is high.

[0036] This invention utilizes the Biefeld-Brown effect. The Biefeld-Brown effect refers to the phenomenon where, when a pair of electrodes (asymmetric capacitors) with specific geometries are placed opposite each other, immersed in an insulating medium, and a suitable voltage is applied, a force is generated attempting to move the device. Reversing the polarity of the electrode voltage does not change the direction of the force, but it does change its magnitude. Specifically, this invention employs a unique hybrid electrode structure and polarity configuration, connecting the needle-tube electrode module in parallel to the high-voltage end and the wire-tube electrode module in parallel to the ground end. This configuration utilizes the superior ionization effect of the needle-tube electrodes to generate strong thrust, while simultaneously using the grounded wire-tube electrodes (the metal wire is physically larger than the needle) to weaken the electric field effect in the direction of positive space charge movement. This design is unfavorable for the flow stream to extend deep into the gap, thereby effectively increasing the device's breakdown voltage. Since thrust is voltage-dependent, a higher withstand voltage directly improves the device's thrust-to-power ratio.

[0037] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0038] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" or "several" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0039] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A hybrid electric propulsion device, characterized in that, include: An insulating support, several needle-tube electrode modules and several wire-tube electrode modules are alternately fixed to the insulating support to form an array structure. Each wire-tube electrode module is connected in parallel to the grounding terminal, and each needle-tube electrode module is connected in parallel to the high-voltage terminal. The wire-tube electrode module includes several wire-tube electrode rods fixed to a conductive support. Each wire-tube electrode rod includes a first metal tube and a metal wire. The metal wire is connected to the conductive support and is kept on the same horizontal plane as the first metal tube.

2. The hybrid electric propulsion device as described in claim 1, characterized in that, The needle-tube electrode module includes several needle-tube electrode rods fixed to a conductive support. Each needle-tube electrode rod includes a second metal tube and a tungsten needle. Several mounting holes are opened on the second metal tube, and tungsten needles are embedded in the mounting holes. The tungsten needles on each needle-tube electrode rod point in the same direction.

3. The hybrid electric propulsion device as described in claim 1 or 2, characterized in that, Several adjustment holes are evenly spaced on the insulating support and the conductive support. The conductive support is fixed to the adjustment holes on the insulating support by an insulating nut so that the distance between the needle-tube electrode module and the wire-tube electrode module can be adjusted. The metal tubes are fixed to the conductive bracket by conductive bolts through adjustment holes so that the spacing between the metal tubes can be adjusted.

4. The hybrid electric propulsion device as described in claim 2, characterized in that, The number of second metal tubes in the needle-tube electrode module is the same as the number of first metal tubes in the wire-tube electrode module, and their positions correspond. The tungsten needle embedded in the second metal tube in the needle-tube electrode module points to the back of the first metal tube at the corresponding position in the previous wire-tube electrode module, and the front of the first metal tube is provided with a metal wire.

5. The hybrid electric propulsion device as described in claim 1 or 2, characterized in that, The metal tube is made of a conductive metal round bar, and the inside of the metal tube is hollow with internal threads at both ends.

6. The hybrid electric propulsion device as described in claim 1, characterized in that, The metal wire is connected to the conductive support by fixing bolts, and the metal wire is taut and located directly above the metal tube.

7. The hybrid electric propulsion device as described in claim 2, characterized in that, The base of the tungsten needle is connected to the mounting hole on the second metal tube by a threaded connection so that the tungsten needle can be embedded in the mounting hole, and the tips of each tungsten needle are kept on the same horizontal plane after being embedded.

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