• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
  • 同族专利
  • 引用文献
  • 法律状态
  • 优先权
    • 专利摘要:
    The propulsion system in orbit by means of floating conductor cables boarded in a spacecraft (1) comprises two sets of electrodynamic conductor cables (2, 3) connected respectively to each of the two poles (4, 5) of a generating source of electrical power (6), and wherein each set is formed by at least one conductor cable. In the presence of a plasma and a magnetic field, as is the case of a satellite orbiting the terrestrial ionosphere, an electric current flows naturally along the conductor cables. As a result of the interaction of the magnetic field with said current, a lorentz force is generated on the cables. Said force can be used to control the orbit of the spacecraft (1) and can be varied, in sense and magnitude, by means of the electric power generating source (6) that allows to modify the intensity and direction of the current throughout of the cables. The efficiency of the system will depend on the spatial environment, the speed of the satellite relative to the plasma, and the properties and design of the cables (length, section and material). The system can be optimized by partially isolating the cables along their length and using materials that favor the emission of electrons by thermionic or photoelectric effect. Said materials will be used in the composition of the cables or to coat their surface along their entire extension or parts of it. Unlike conventional propulsion systems, such as chemical or electric rockets, or electrodynamic cables proposed to date, the proposed system does not require either propellants or expellers. (Machine-translation by Google Translate, not legally binding)
    公开号:ES2569540A1
    申请号:ES201531649
    申请日:2015-11-13
    公开日:2016-05-11
    发明作者:Gonzalo SÁNCHEZ ARRIAGA；Claudio Bombardelli
    申请人:Universidad Politecnica de Madrid；Universidad Carlos III de Madrid；
    IPC主号:
    专利说明:

    image 1
    DESCRIPTION PROPULSION SYSTEM IN ORBIT THROUGH FLOATING DRIVING CABLES
    5 Technical Field of the Invention
    The present invention is framed in the field of electromagnetic propulsion of aerospace systems. In particular, those systems that employ long
    10 conductive cables as elements for the conversion of electrical energy into orbital energy of the satellite thanks to the force of Lorentz exerted by the magnetic field of the planet on the current flowing through the cable. State of the Art
    15 Space vehicles, such as satellites or space stations, require propulsion devices that allow them to accelerate them to perform orbital maneuvers, such as orbit changes or controlled approach to other vehicles or objects in orbit (in English / French "Rendezvous -vous "). They are also necessary for
    20 to compensate for the action of small disturbing forces that, acting continuously, would end up removing vehicles from their orbit if no action was taken.
    The most commonly used propulsion systems include rockets
    25 chemical and electrical. Both rely on Newton's third Law, Action-Reaction Law. When a jet of gas is expelled at high speed through a nozzle, a thrust force is produced on the satellite. The rockets need both mass of fuel and energy to accelerate the jets. In the case of chemists, energy comes from chemical reactions produced by burning the fuel. In
    30 The electric satellites must be equipped with an electric power generating source that is used to generate an electromagnetic field that accelerates the previously ionized fuel (plasma).
    The need for a mass of fuel to operate is doubly harmful. On the one hand, it increases the costs of launching since it increases the mass of the satellite, and on the other, once the fuel is finished, the engine stops running, thus ending the useful life of the satellite. In the case of electric propulsion, the on-board electrical power system typically requires the use of heavy solar panels. These reasons have pushed the space sector to the
    image2
    image3
    5 search for alternative propulsion systems such as solar candles or lasers or microwaves sent from Earth.
    In the case of satellites in orbit around planets endowed with a magnetic field and ionosphere, such as Earth or Jupiter, there is another physical mechanism, different from the Law of Action-Reaction, which can be used: the Lorentz force exerted by the magnetic field on the current flowing through a cable [Drell, S., Foley, HM, Ruderman, MA Drag and propulsion of large satellites in the ionosphere: an Alfven propulsion engine in space, Journal of Geophysical Research, Vol 70, 13, pp 31313145, 1965]. One of the key aspects of this technology is load sharing
    15 electric with the ambient plasma that allow to close the circuit and circulate a regular current through the cable. As explained below, this technical problem has been solved in such a way that the system achieves a high degree of simplicity.
    In 1993, it was proposed to leave the conductor cable bare, that is, without insulation and place
    20 at one end of it a plasma contactor or hollow cathode [Sanmartín, J., Martínez-Sánchez, M and Ahedo, E., Bare wire anodes for electrodynamic tethers, Journal of Propulsion and Power, Vol 9, 3, pp 353 -359, 1993]. Except in a very small segment near the cathode, the cable acts as a Langmuir collector probe and captures electrons from the ambient plasma naturally. The cathode generates
    25 a path of low impedance for electrons, which are returned to the plasma giving rise to a stationary current along the cable (see figure 3). At work [Sanmartín, J., Martínez-Sánchez, M and Ahedo, E., Bare wire anodes for electrodynamic tethers, Journal of Propulsion and Power, Vol 9, 3, pp 353-359, 1993] two ways of proposing Cable operation In passive mode for a vehicle
    30 in low orbit around the Earth, the system does not carry an external power source and produces electrical power on board while the vehicle loses orbital energy. In the active mode an operation scheme was introduced where there is an external source of electrical power between the end of the cable and the hollow cathode. The electromotive force of said source gives control over the current and therefore also over
    35 Lorentz's strength.
    image4
    image5
    However, the operation of the cathode requires an inert gas storage system and a device to control its flow. Throughout its life, the cathode loses efficiency because it erodes and, when the inert gas runs out, it stops working
    5 totally. As an alternative to traditional hollow cathodes, devices that do not require gas such as FEACs (Field emission array cathodes) or thermionic emitters have been proposed. Currently, the electron emission capacity of such devices is far from traditional hollow cathodes.
    10 When no active cathode (such as a plasma contactor or a hollow cathode) is used, the cable is said to be floating. In that case it is necessary to find a physical mechanism that allows the cable to emit electrons by itself. To date, two have been proposed. The first is the emission of secondary electrons that are
    15 occurs when the negative polarized cable segment receives the impact of ambient plasma ions [Sanmartín, J., Charro, M., Peláez, J., Tinao, I., Elaskar, S., Hilgers, A. and Martínez-Sánchez, M., Floating bare tether as upper atmosphere probe, Journal of Geophysical Research, Vol 111, A11310, 1-15, 2006]. However, when compared to electron capture in the anodic segment, the efficiency
    20 of the secondary emission is low. For this reason, in 2012 a second physical mechanism was proposed: the thermionic emission that occurs if the cable is coated with a material with high electronic emissivity (low work function) [Williams, JD, Sanmartín, J. and Rand, LP , Low-Work function coating for entirely propellantless bare electrodynamic tether, lEEE Transactionson Plasma Science, Vol 40, 5, pp 1441
    25 1445, 2012]. The most promising thermionic material for this application is C12A7: e-which shows emission properties and stability far superior to other ceramic coatings, including LaB6, CeB6, BaO-W, Ba-W, BaO and 12CaO -7Al2O3 (C12A7: e-).
    30 It is important to note that previous work on floating cables (without active cathode) has been proposed to excite aurora borealis artificially [Sanmartín, J., Charro, M., Peláez, J., Tinao, I., Elaskar, S., Hilgers, A. and Martínez-Sánchez, M., Floating bare tether as upper atmosphere probe, Journal of Geophysical Research, Vol 111, A11310, 1-15, 2006] and to de-orbit satellites [Williams, JD, Sanmartín, J .and
    35 Rand, L. P., Low-Work function coating for entirely propellantless bare electrodynamic
    image6
    image7
    tether, lEEE Transactionson Plasma Science, Vol 40, 5, pp 1441-1445, 2012]. Unlike the present invention, in these two works the cable works passively and there is no active electrical power source that feeds the cable. All previous designs based on electrodynamic cables in active mode (with external power source) have not been of the floating type, since they consist of a hollow cathode-type electron transmitter or FEAC (patents: US 6459206 B1, US 6755377 B1, US 6758443 B1, US 6419191 B1, US 7118074 B1). In them the external source of electrical power is at one end of the cable. Brief Description of the Invention
    In the present invention a new design of floating cables is proposed, where the cables themselves are responsible for the capture and emission of electrons, and the power generating source is connected to the ends of two sets of conductor cables, and where each of the two sets of conductor cables is constituted by at least one conductor cable. For the first time, the photoelectric emission by the cables is contemplated as a physical mechanism to achieve cathodic contact with the ambient plasma. The invention describes how cables should be designed so that both electron emission mechanisms are efficient. Some materials that could facilitate photoelectric emission are alkali metals or compounds Ag-Cs2O-Cs, Ag-Cs3Sb, and Na2KSb.
    The present invention relates to an orbit propulsion system for space vehicles or satellites characterized in that it comprises two sets of floating electrodynamic conductor cables (2,3) connected respectively to each of the two poles (4,5) of a source electric power generator (6) on board a spacecraft in orbit (1).
    The design of the system corresponding to the present invention can be modified according to the needs of the space mission or application that uses it. The modifications include:
    -Possible use of different types of sections (substantially
    circular, substantially rectangular or ribbon, and in shape
    substantially annular) for cables.
    image8
    image9
    -the possible use of high electronic emissivity materials (by thermionic or photoelectric effect) for the composition of the cables and / or to cover their surfaces. -the possible use of dielectric materials to isolate parts of the surface
    5 of the cables. -the possible use of materials or treatments that provide a high ratio of absorptivity to thermal emissivity in the cables so that they reach higher temperatures and increase their electronic emissivity. -the possible use of limb masses connected with one or more cables
    10 at the opposite ends of the connection poles of the electrical power utilization or storage system, to improve the dynamic stability of the cables, and which may include, among others, a passive ballast mass, cable deployment system, other satellite, dock, satellite top. -Possible use of multiple cables, not necessarily of the same design,
    15 geometric characteristics or composition, connected to the same pole. -each set of conductor cables formed by two or more conductor cables can have their conductors electrically connected to each other along their extension at one or more points. -at least one of the electrodynamic cables can be substantially
    20 made of materials that include at least one of the following: graphene, aluminum alloys, copper, beryllium-copper alloys. Description of the figures
    In order to complete the description and in order to help a better understanding of the features of the invention, the present specification of figures 1, 2 and 3 is attached as an integral part thereof.
    The invention will be described in more detail below with reference to a
    30 exemplary embodiment thereof depicted in Figures 1 and 2. Figure 3 reflects the state of the art, and is added to underline the comparative novelty of the present invention.
    Figure 1 presents the basic design and operation scheme of the invention. 35 Figure 2 explains the physical mechanism by which the cables exchange charge with the surrounding plasma and a steady current is achieved along them which gives rise to a Lorentz force.
    image10
    image11
    5 Figure 3 shows the classic design of a propulsion system based on a bare electrodynamic cable [Sanmartín, J., Martínez-Sánchez, M and Ahedo, E., Bare wire anodes for electrodynamic tethers, Journal of Propulsion and Power, Vol 9, 3, pp 353-359, 1993]. Unlike the present invention, this design makes use of a single electrodynamic cable connected at one end to a space vehicle (7) and
    10 a load (8), and at the other end to a limb mass (9). The cable, which consists of an isolated part of length LI and a bare part of length LB, captures electrons from the surrounding plasma. The emission of electrons, necessary to close the circuit and achieve a stationary current in the cable, is obtained by means of a hollow cathode (in English "hollow cathode") on board the space vehicle.
    15 All orbit propulsion system designs using electrodynamic cables that have been considered so far use a similar scheme. Detailed description of the invention
    The design and operation of the invention can be easily understood by referring to Figure 1. From the space vehicle (1) two sets of bare conductor cables (2) and (3) are deployed, that is, not electrically insulated with with respect to the surrounding plasma along its full extent or part of it. In this particular example, each set consists of three
    25 wires The cables belonging to the assembly (2) are electrically connected to the negative pole (4) while the cables belonging to the assembly (3) are electrically connected to the positive pole (5). A power generating source (6) is connected to the two poles (4) and (5).
    30 The cables interact with the surrounding environment, characterized by the presence of a magnetic field B and an ionosphere. Due to the vrel orbital movement of the space vehicle with respect to the highly conductive ionospheric plasma, there is an electromotor electric field E = vrel x B in the far plasma in the referential linked to the vehicle and a current I flows along the cables. This current crosses the
    35 source generating electric power (6), and its intensity and direction can be controlled thanks to the electromotive force it supplies. The Lorentz force of the magnetic field on the current propels the space vehicle (1).
    image12
    image13
    The basic physical principles of the operation of the invention will be explained in
    5 continued with reference to figure 2. In this particular example, two cables, of length L1 and L2, respectively, are connected to an electric power generator. Due to the orbital movement of the space vehicle, there is a vrel velocity between the cable and the ionospheric plasma. As a consequence, of said velocity and the presence of magnetic field B, there is an electric field in the far plasma
    10 vrelx B electric motor, in a reference system linked to the cable. Assuming that the projection of the electric motor field according to the direction tangent to the cables Et is constant, the electrical potential of the far plasma (Vplasma) varies linearly along the direction of the cables. The total potential rise between the cable ends is ∆Vplasma = Et (L1 + L2). On the other hand, the electrical potential of the cables
    15 (Vtether) remains approximately constant throughout its lengths, as long as the ohmic effects of them are contemplated, as is reasonable for a preliminary analysis. However, when passing from one pole to the other, a potential rise (Ɛ) is verified due to the presence of the source of electric power generation.
    20 At those points where the potential of the cable is greater than that of the distant plasma, the cable will capture electrons like a Langmuir collector probe. At those points where the potential of the cable is less than that of the distant plasma, the cable will emit electrons, either due to the impact of ions or because the manufactured cable is found or
    25 covered with a material of high electronic emissivity (low working function), which facilitates the emission by thermionic or photoelectric effects when solar radiation strikes the cable. The simplest case is that shown in Figure 2 where a segment (of length L2B) of the lower wire captures electrons, its isolated complementary segment (of length L2I) does not exchange charge with the plasma, and the cable
    30 upper emits electrons along its entire length L1. The efficiency of the cables as a propulsion system depends on the environmental conditions (magnetic field and plasma density), design of the cables (section, material and length) and the electromotive force provided by the generating source of electrical power. Depending on the mission, it will be necessary to carefully design the system, image14
    35 which may differ from that shown in the example of Figure 2.
    image15
    Being the electrons of the ambient plasma captured and emitted in different sections of each cable, a current profile (I) is finally obtained that varies along the cables. It is important to note that the current becomes zero at the free ends of the cables because these are floating. The current profile depends on the electromotive force (Ɛ) provided by the electric power generating source, which gives control over the Lorentz force exerted by the magnetic field on it. It is important to note that, if Ɛ is large enough, the direction of the current along the cable will be contrary to its natural sense, which is given by the field
    10 electric motor Et. This is the case represented in Figure 2.
    Control over the direction of the current is one of the key aspects of the system. For example, in the case of a satellite in low orbit around the Earth, if the cable system does not consist of any source of electrical power, the current flows
    15 in the sense of Et. In this case the Lorentz force produces the satellite re-entry. However, if Ɛ is high enough, the current flows in the opposite direction to Et and the satellite would gain height or could be used to compensate for the weak aerodynamic drag. A propulsion force is thus achieved without using any type of propellant or expelling.
    20 A key advantage of the proposed design for this invention is its robustness. If any cable were cut during its operation, for example due to an impact of a micro-meteoroid or space debris fragment, the life of the satellite would not be compromised. A floating cable whose length has been reduced by a cut
    25 stops working; continues to capture or emit electrons, although the efficiency of the system will be reduced by an amount that will depend on the length of the cable cut.
    To increase the efficiency of the system, materials or coatings of materials with high electronic emissivity can be used (thermionic materials with low function
    30 work). Said coatings or materials may be used in one or more floating cables and along their entire length or in a segment thereof. The system can be optimized by isolating cable segments. For example, one or more of the electrodynamic cables may be composed of a conductive substrate covered along its entire length or part of it by a material that
    35 facilitates the emission of electrons by thermionic or photoelectric effect.
    image16
    image17
    A key aspect is the selection of cable dimensions (lengths and cross section). As an example, the steps to follow to obtain an optimal design in the case of a system consisting of a bare conductor cable followed by an insulated conductor segment, the source of electrical power and a conductor cable covered with a material are described below. High electronic emissivity (see figure 2). Although this model must be adapted to the specific configuration to be studied, for example, add more cables or isolate more segments, the design scheme is always similar. For example, at least one of the cables connected to one of the poles may be covered with a material that facilitates photoelectric emission, and at least one of the cables connected to the other pole may have the segment closest to the electrically insulated pole with respect to the plasma.
    First of all it is necessary to calculate the current and potential profiles along the cable. In the case of Figure 2, if ohmic effects are neglected, the potential difference between the cable and the plasma is valid
     V - Ex x <L
    0 t 1
    V () ≡ V () −Vx
    xx () =  (0.1)
    tether plasma
    V + ε - Ex L <x <L
     0 t 1
    where V <0 is the potential difference between the cable and the far plasma for x = 0 and
    0
    L = L1 + L2.
    Second, the current profile consistent with equation (0.1) is calculated. In segment 0 <x ≤ L1, a perimeter wire allows electrons thanks to three different physical effects according to equation (1.2):
    dI ⎡∞ 2  W  eN0 image18 2e | V (x) | 
    = p e SUYU () () dU + aT exp - +
    (1 + γ | V (x) |)  (0.2)
    t ⎢∫ ⎜⎟
    kT i
    dx  0  B ⎠π m 
    The first term represents the photoelectric effect and involves the solar flow S (U) of incident energy in the cable (number of photons per unit of time, surface and energy U) and the quantum yield Y (U) (in English "photoelectric yield ") of the cable, that is, the number of photoelectrons extracted per incident energy photon U. The
    Photoelectric emission by the cable itself has not been previously proposed in bare electrodynamic cable applications. The second term is the issue
    image19
    image20
    thermionics, proposed in Ref. [Williams, JD, Sanmartín, J. and Rand, LP, Low-Work function coating for entirely propellantless bare electrodynamic tether, lEEE Transactionson Plasma Science, Vol 40, 5, pp 1441-1445, 2012] . This mechanism
    6
    It involves the Richardson constant (a = 1.2 × 10 A / m2K2), the Boltzmann constant (kB) and the temperature (T) and working function of the cable (W), respectively. The Ec.
    (0.2) assumes for simplicity that the emitted thermal current is given by the Richardson-Dushman law, ignoring the Schottky and space-charge-limited effect. The third term is the current emitted when the cable receives the impact of the ions, a mechanism proposed in Ref. [Sanmartín, J., Charro, M., Peláez, J., Tinao, I., Elaskar, S., Hilgers, A. and Martínez-Sánchez, M., Floating bare tether as upper atmosphere probe, Journal of Geophysical Research, Vol 111, A11310, 1-15, 2006].
    It depends on the plasma density (N0), the mass (mi) of the plasma ions, the electron charge (e) and the product γ | ∆V | which represents the number of electrons emitted per ion that impacts.
    Depending on the design of the cables, for example that they are covered or not with a material with low W or high Y (U), and their operation (temperature that they can reach), it is expected that one of the three terms will dominate About the rest.
    The segment L1 <x ≤ L1 + L2 I is electrically isolated from the plasma so that the current remains constant along x:
    gave
    = 0 L <x ≤ L + L (0.3)
    1 12 I
    dx
    Finally, a good approximation for modeling the captured electrons in the segment L + L ≤ x <L is the Orbital-Motion-Limited (OML) law at high rate
    12 I
    potential difference V (x) [Sanmartín, J., Martínez-Sánchez, M and Ahedo, E., Bare wire anodes for electrodynamic tethers, Journal of Propulsion and Power, Vol 9, 3, pp 353-359, 1993]:
    dIepN image21 x
    t 02eV ()
    = -
    L + L ≤ x <L (0.4)
    12 I
    dx π me
    The integration of Equations (0.2), (0.3) and (0.4) with the potential given by (0.1) and image22 boundary conditions I (0) = I (L) = 0 provides the current profile I (x)
    image23
    t
    Once the current profile is known, the figures of merit are constructed:
    ∫ L
    5 Lorentz force (thrust) F = I × Bdx,
    0 F ⋅ v
    Thrust efficiency η = orb,
    ε
    IG F ⋅ v
    Useful mechanical power per unit mass κ = orb,
    m
    t
    δ∞ dG
    Probability of cut Nc = - π L∆tD (δ) dδ,
    mission ∫ eff
    min
    δ dδ
    which have been previously proposed for electrodynamic cables
    10 traditional equipped with plasma contactors [Sanmartín, J., Martínez-Sánchez, M and Ahedo, E., Bare wire anodes for electrodynamic tethers, Journal of Propulsion and Power, Vol 9, 3, pp 353-359, 1993] [ J. Sanmartín, A. Sánchez-Torres, S. B. Khan,
    G. Sánchez-Arriaga and M. Charro, Optimimum sizing of bare-tethers for de-orbiting satellites at end of mission, Advances in Space Research 56, 7, 1485-1492, 2015].
    15 In the previous equations the total mass of the cables mt, speed has been defined
    orbital v, the expected mission time ∆t, effective diameter of cable D, the
    orb mission eff
    flow of micrometeoroids G with size δ, the maximum size of micrometeoroid δ∞ and the minimum size that the cable δmin can cut. Depending on the mission,
    20 select the most interesting figures of merit for the particular application and select the dimensions of the cables that maximize them (or minimize in the case of Nc).
    The above description should be understood as an exemplary embodiment with the sole
    25 to illustrate the operation and optimization of the system and not as a universal design.
    A crucial aspect in the optimal design of the system in the case in which it is intended image24
    image25
    aspect is critical due to the exponential behavior of the current emitted with the
    W kT factor image26 in equation (0.2). Ignoring warming by Joule effect and
    B
    energy contributed by the electrons when impacting the anodic segment, the equilibrium temperature Teq of the cable is determined by a balance between solar heating and radiative cooling according to the equation:
    ⎛α ⎞14 image27
    abs S
    Teq =   (0.5)
    ε πσ
     emit B 
    where S is the solar constant, σ the Stefan-Boltzmann constant and α and ε the
    B abs emis
    absorptivity and emissivity of the cable.
    10 In order to have reasonable efficiency values, the densities of emitted and captured current must be of the same order, which provides the following link between the work function of the material and its temperature [see equations (0.2) and (0.4)]
     eN image28 THE 
    W ≈− k T B eq ln  0 t  (0.6)
     ⎟
    AπT 2 m
     eq e 
    15 The quotient selection α image29 ε in equation (0.5) is critical since the
    abs emis
    Temperature must be within a certain operating range. The cable must be hot to favor the emission of electrons by thermionic effect but without exceeding the temperature limit above which the material loses mechanical properties. The state of the art of the work functions of the LaB6 and 20 CeB6 materials are around 2.5 eV and for the C12A7 electride: e-can potentially be 0.65 eV [Y. Toda, K. Kobayashi, K. Hayashi, S. Ueda, T. Kamiya, M. Hirano and H. Hosono, Field Emission of Electron anions clathrated in subnanometersized cages in [Ca24Al28O 64] 4+ (4e-), Adv. Matter, 16, 685-689, 2004]. These values, together with the environmental parameters of Et and N0 in low orbit around the Earth, 25 indicate that the temperature of the cable must be between 300 and 1000 K (higher if the conductive material can withstand it). These two temperatures lead
    to α ratios image30 ε about 1 and 130, respectively.
    abs emis
    image31
    权利要求:
    Claims (15)
    [1]
    image 1
    1. Propulsion system in orbit by means of floating conductor cables embarked on a space vehicle (1) characterized in that it comprises two
    5 sets of electrodynamic conductive cables (2,3) respectively connected to each of the two poles (4,5) of an electric power generating source (6)), and where each set is formed by at least one conductor cable .
    A system according to claim 1 wherein each set of conductor cables formed by two or more conductor cables has their conductors electrically connected to each other along their extension at one or more points.
    [3]
    3. System according to any one of claims 1, 2, wherein at least one of
    15 its electrodynamic cables have an end mass connected at the opposite end to the connection pole with the source of electric power generation.
    [4]
    4. System according to claim 3 wherein the limb mass comprises the
    20 minus one of the following elements: passive ballast mass, cable deployment system, other satellite, dock, satellite cover.
    [5]
    5. System according to any one of claims 1, 2, 3, 4, wherein one or more
    of its electrodynamic cables has a substantially circular section. 25
    [6]
    6. System according to any one of claims 1, 2, 3, 4, wherein one or more of its electrodynamic cables has substantially annular section.
    [7]
    7. System according to any one of claims 1, 2, 3, 4, wherein one or more of its electrodynamic cables is substantially tape-shaped.
    [8]
    8. System according to any one of the preceding claims wherein at least one of its electrodynamic cables is composed of a material that facilitates the emission of electrons by thermionic or photoelectric effect.
    35
    image2
    image3
    [9]
    9. System according to claim 8 wherein the material that facilitates the emission of electrons by thermionic effect includes at least one of the following compounds: LaB6, CeB6, BaO-W, Ba-W, BaO, and 12CaO-7Al2O3 (C12A7: e -).
    A system according to claim 8 wherein the material that facilitates the emission of electrons by photoelectric effect includes at least one alkali metal or some of the compounds Ag-Cs2O-Cs, Ag-Cs3Sb and Na2KSb.
    [11]
    11. System according to any one of claims 1, 2, 3, 4, 5, 6, 7, wherein one
    10 or more of its electrodynamic cables are composed of a conductive substrate covered along its entire length or part of it by a material that facilitates the emission of electrons by thermionic or photoelectric effect.
    [12]
    12. System according to claim 11 wherein the material that facilitates the emission by
    The thermionic effect includes at least one of the following: LaB6, CeB6, BaO-W, Ba-W, BaO, and 12CaO-7Al2O3 (C12A7: e-).
    [13]
    13. System according to claim 11 wherein the material that facilitates the emission by
    Photoelectric effect includes at least one alkali metal or any of the compounds 20 Ag-Cs2O-Cs, Ag-Cs3Sb, and Na2KSb
    [14]
    14. System according to any one of claims 1, 2, 3, 4, 5, 6, 7, wherein one
    or more of its electrodynamic cables is coated along its extension
    complete or part of it by an insulating material. 25
    [15]
    15. System according to any one of claims 1, 2, 3, 4, 5, 6, 7, 11, 12, 13, 14, wherein at least one of its electrodynamic cables is substantially made of materials that include at least one of the following: graphene, aluminum, copper alloys, beryllium-copper alloys.
    30
    [16]
    16. System according to claim 15 wherein the surface of one or more of its cables has been prepared to achieve a high absorptivity / emissivity ratio image4 thermal in order to obtain high temperatures that favor the thermics of the coating.
    35
    image5
    [17]
    17. System according to any one of claims 1, 2, 3, 4, 5, 6, 7, wherein at least one of the cables connected to one of the poles is covered with a material that facilitates photoelectric emission, and at At least one of the cables connected to the other pole has the segment closest to the electrically insulated pole with respect to the plasma.
    image6
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    同族专利:
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    WO2017081351A1|2017-05-18|
    EP3375714A4|2018-11-21|
    EP3375714B1|2020-07-22|
    EP3375714A1|2018-09-19|
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