An inertial electrostatic confinement fusion device neutralized by electron injection

Abstract

This invention relates to an inertial electrostatic confinement fusion device with electron injection neutralization, comprising a cathode sphere, an anode, a cathode high-voltage introduction support rod, a high-energy electron injection gun, a vacuum system, and a high-voltage power supply system. The high-energy electron injection gun and the electron injection gun within the sphere inject neutralizing electrons into the sphere and between the sphere and the anode of the inertial electrostatic confinement fusion device, thereby reducing or eliminating the space charge force generated by deuterium ions, increasing the deuterium ion density within the sphere, and thus improving neutron yield and break-even ratio.

Description

Technical Field

[0001] The field covered by this patent is nuclear fusion and neutron sources. Background Technology

[0002] Nuclear fusion power generation is a fundamental solution to humanity's future energy needs. Currently, there are many types of nuclear fusion technologies both domestically and internationally, with four main approaches: tokamak, laser inertial confinement, Z-pinch, and inertial electrostatic confinement. Each of these technologies has its own advantages and disadvantages. Among them, inertial electrostatic confinement devices are the smallest and consume the least amount of electricity. They do not face the challenges of fusion ignition or complex plasma dynamics. Their main drawback is a relatively low neutron yield, currently far from energy break-even. These disadvantages limit the development and application of inertial electrostatic confinement fusion devices.

[0003] The structure of an inertial electrostatic confinement device (IGCD) generally consists of a small spherical mesh (or simply mesh) placed at the center of a grounded spherical vacuum cavity. The mesh serves as the cathode, and a negative high voltage is introduced through the cathode and fixed to a support rod (or cathode rod), thus applying the negative high voltage. Currently, the working pressure of IGDs abroad ranges from tens of Pa to 10 Pa. -2 Pa, with input power ranging from hundreds of watts to several kilowatts, and an average neutron yield of up to 10. 8 The fusion power output is on the order of n / s, corresponding to a fusion energy output in the order of mW. For a power input of 1 kilowatt, the neutron yield required to achieve energy break-even is 5 × 10⁻⁶. 14 The ratio is above n / s. Therefore, how to increase fusion power and neutron yield under the same high-voltage input power is a key issue that needs to be addressed to achieve break-even.

[0004] The main reason for the low fusion power output of current inertial electrostatic confinement devices is the extremely low deuterium ion number density within the sphere, with experimental measurements showing a value of 10. 9 / m 3 -10 10 / m 3 The minimum plasma density required for a tokamak is 10. 20 / m 3 Therefore, increasing the deuterium ion number density within the fusion grid is a key issue in improving fusion power generation.

[0005] When an inertial electrostatic confinement device is powered by a high voltage, the deuterium molecules between the grounded spherical shell and the negatively charged mesh are ionized under the influence of the high-voltage electric field. Electrons generated by ionization move directly towards the shell and are lost, while deuterium ions pass through the mesh and oscillate around it. Therefore, plasma is difficult to form in the space between the shell and the mesh, resulting in a positively charged space. This space is difficult to neutralize, but due to the fixed potential of the mesh cathode, the deuterium ion density inside the mesh will not be affected unless it is extremely high. However, if the deuterium ion density outside the mesh is too high, causing an excessively high electric field strength, high-voltage arcing can easily occur, which is a problem that needs to be addressed.

[0006] Inside the net, although the applied high voltage does not create a potential difference (i.e., the net should be at the same potential), a high deuterium ion current (i.e., a high deuterium ion number density) will create a potential distribution. The closer to the center of the net, the higher the deuterium ion number density and the higher the potential, thus forming a virtual anode within the net. The high-density incident deuterium ion current ionizes the deuterium gas molecules inside the net. The resulting electrons oscillate around the virtual anode, increasing the electron density at the center of the net. If the potential of the virtual anode is very high, the focusing effect of ionized electrons is enhanced, thus lowering the center potential of the virtual anode, forming a virtual cathode at the center. If the net size is large and the deuterium ion current is further increased, smaller virtual anodes are formed inside the virtual cathodes, and this process repeats to form multiple potential wells. Figure 1 As shown, 11 represents the position of the sphere grid, 2 represents the grounded sphere as the anode of the inertial electrostatic confinement device, 31 represents the virtual cathode, 41 represents the virtual anode, and 51 represents the potential distribution curve.

[0007] The aforementioned multiple potential wells can mitigate the influence of space charge force on the deuterium number density at the focal point to some extent, but they still have a significant negative impact on further increasing the deuterium number density at the focal point. This is because a large number of low-energy deuterium ions are generated in the inertial electrostatic confinement device, and due to the presence of multiple potential wells, they cannot reach the focal point, making it difficult to further increase the deuterium number density.

[0008] In summary, solving the problem of multiple potential wells is a key issue for further improving the neutron yield of inertial electrostatic confinement devices and achieving break-even. Summary of the Invention

[0009] To address the aforementioned challenges, this patent proposes an electron injection neutralization technique to improve the neutron yield and break-even ratio of fusion devices (the break-even ratio is the ratio of the device's total output energy to its total input energy). The injected electrons can form a special plasma with the positive charges within the device, reducing or eliminating the space charge force generated by the positive charges. Electron injection neutralization comprises two parts: first, high-energy electron injection onto the Earth's crust; and second, internal electron injection within the spherical grid.

[0010] The technical solution of the present invention is as follows: an inertial electrostatic confinement fusion device with electron injection neutralization, comprising an anode, a cathode, a cathode rod connected to the cathode, a high-energy electron injection gun, an electron injection gun in a sphere, a vacuum system, a high-voltage power supply system, etc.

[0011] Furthermore, in the electron-injection-neutralized inertial electrostatic confinement fusion device described above, the cathode adopts a mesh-like spherical structure (referred to as a sphere mesh) and is connected to a negative high-voltage power supply through the cathode rod; the anode of the inertial electrostatic confinement fusion device is grounded as the vacuum cavity wall.

[0012] Furthermore, in the electron injection-neutralized inertial electrostatic confinement fusion device described above, the high-energy electron injection involves placing an electron gun on the anode of the inertial electrostatic confinement fusion device. The electron gun cathode is insulated from the anode and is subjected to a negative high voltage, typically below 10V, relative to the cathode sphere of the inertial electrostatic confinement fusion device. Electrons emitted from the electron gun move from the anode into the sphere and are decelerated to approximately 10eV. A small amount of electron loss occurs before entering the sphere. After entering the sphere, due to their low energy, a large number of electrons undergo elastic collisions with deuterium molecules and aggregated deuterium ions at approximately 1 Pa, and are confined within the sphere by the multiple potential wells, thereby reducing the potential height of the multiple potential wells. The high-energy electron injection method can neutralize the space charge force of deuterium ions within the sphere and between the sphere and the anode of the inertial electrostatic confinement fusion device. The advantages of high-energy electron injection methods are simple structure, easy installation and operation, while the disadvantages are low efficiency of electron capture by the ball net and high high-voltage power consumption.

[0013] Furthermore, in the electron-injection neutralized inertial electrostatic confinement fusion device described above, the internal electron injection within the sphere involves installing an electron gun at the connection point between the cathode rod and the sphere. Electrons emitted from the electron gun move towards the center of the sphere. The cathode potential of the electron gun is higher than that of the cathode of the sphere, thus preventing electrons injected into the sphere from escaping. The anode potential of the electron gun is higher than that of the electron gun cathode. The extraction current of the electron gun is related to the extraction voltage to the power of 3 / 2. To increase the electron extraction current, the extraction voltage needs to be increased. However, if the extraction voltage is too high, it will disrupt the potential distribution within the sphere, hindering the formation of a high-density deuterium ion anode. Therefore, a low-potential shield needs to be wrapped around the electron gun anode to slow down the extracted electrons. As electrons move towards the anode, the deuterium ion density increases, and electrons are easily subjected to elastic scattering, leading to changes in their trajectories. Consequently, most electrons, while oscillating around the virtual cathode, cannot return to the electron gun's emission port and are lost. To further reduce electron loss due to electron return to the electron gun, the direction of electron emission can be slightly offset from the center of the net. This utilizes the centripetal force of the spherically distributed deuterium ions to deflect the electrons. The advantages of internal electron injection are that it effectively neutralizes deuterium ions inside the net, reduces or eliminates multiple potential wells within the net, increases the plasma density at the focal point, and consumes less power from the high-voltage electron gun. The disadvantages are that the net diameter is relatively small, typically around 10 cm, resulting in limited installation space and greater difficulty in installing the electron gun.

[0014] The beneficial effects of the present invention are as follows: The electron-injection neutralized inertial electrostatic confinement fusion device provided by the present invention can neutralize deuterium ions in the grid and between the grid and the anode of the inertial electrostatic confinement fusion device by using high-energy electron injection and in-grid electron injection, reduce or eliminate multiple potential traps in the grid, and increase the deuterium ion density in the grid, thereby increasing neutron yield and break-even ratio. Attached Figure Description

[0015] Figure 1 A schematic diagram of multiple potential wells for an inertial electrostatic confinement fusion device;

[0016] Figure 2 This is a schematic diagram of the structure of the inertial electrostatic confinement fusion device with high-energy electron injection in an embodiment of the present invention.

[0017] Figure 3 This is a schematic diagram of the high-energy electron injection electron gun structure in an embodiment of the present invention.

[0018] Figure 4 This is a schematic diagram of the internal electron injection gun structure inside the net in an embodiment of the present invention. Detailed Implementation Plan

[0019] The embodiments of the present invention will be further described below with reference to the accompanying drawings.

[0020] Figure 2 The electron-injection neutralized inertial electrostatic confinement fusion device shown comprises a cathode 1, an anode 2, a high-voltage input support rod 3 connected to the cathode, a high-energy electron injection gun 32, an electron injection gun within the sphere, a vacuum system, and a high-voltage power supply system. The vacuum system is used to maintain the vacuum environment inside the sphere and inject low-pressure deuterium gas; the high-voltage power supply system is used to generate a negative high-voltage potential.

[0021] The deuterium gas pressure inside anode 2 ranges from tens of Pa to 10 Pa. -4 Pa. The anode 2 of the inertial electrostatic confinement device is grounded as the vacuum cavity wall. The cathode 1 of the inertial electrostatic confinement device adopts a mesh spherical structure and is connected to a negative high voltage of -50KV through the cathode rod 3. The cathode rod 3 is insulated from the anode 1. The electron trajectory output by the high-energy electron injection electron gun 32 is a straight track 41. After entering the spherical mesh cathode 1, the electrons will undergo elastic scattering with a certain probability, thus being captured within the spherical mesh cathode.

[0022] Figure 3 The high-energy electron injection electron gun 32 shown includes an electron gun cathode 321 and an electron gun anode 322. The electron gun cathode 321 is loaded with a high voltage of -50.01 kV, and the electron gun anode 322 can be directly connected to the anode 2 of the inertial electrostatic confinement fusion device. The energy of electrons entering the sphere is about 10 eV, and they are captured by the sphere through elastic scattering with deuterium ions in the sphere.

[0023] Figure 4 This is a partial view of the connection between the high-voltage introduction support rod 3 and the cathode 1 of the ball net. The electron gun inside the ball net, as shown, includes an electron gun cathode 341, an electron gun anode 342, and a low-potential shield 343. The potential of the electron gun cathode 341 is -49.95 kV, the potential of the electron gun anode 342 is -48 kV, and the potential of the low-potential shield 343 is -49.9 kV. Electrons are first drawn out from the electron gun cathode 341 under the influence of a 1.95 kV voltage between the electron gun cathode 341 and the electron gun anode 342. Then, the low-potential shield 343 slows down the electron energy to 50 eV. During the movement of the electrons towards the virtual anode inside the ball net, elastic scattering occurs with a large number of deuterium ions, changing the direction of electron movement and preventing the electrons from returning to the electron gun. To further reduce the possibility of electrons returning to the electron gun, the trajectory of the electrons emitted from the electron gun can be deviated from the center of the net by as little as 1 cm. In this way, even if the electrons do not undergo elastic scattering with the deuterium ions, they will change their direction of motion under the influence of the central force field.

[0024] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention is also intended to include these modifications and variations.

Claims

1. An inertial electrostatic confinement fusion device with electron injection neutralization, comprising a cathode, an anode, a cathode high-voltage introduction support rod, a high-energy electron injection gun, an electron injection gun within a sphere, a vacuum system, and a high-voltage power supply system, characterized in that: The anode is a spherical vacuum cavity; the cathode is a spherical mesh structure placed at the center within the spherical vacuum cavity; a high-voltage cathode support rod is used to support and fix the spherical mesh, and to apply a negative high voltage to the mesh, while simultaneously insulating and sealing it from the spherical vacuum cavity; a high-energy electron injection gun and an in-mesh electron injection gun inject neutralizing electrons into the mesh; a vacuum system is used to maintain the vacuum environment within the spherical vacuum cavity and to input low-pressure deuterium gas; a high-voltage power supply system is used to generate a negative high-voltage potential; the high-energy electron injection gun is mounted on the spherical vacuum cavity, with the electron gun cathode potential lower than the mesh potential, and the electron gun... The anode potential is equal to that of the spherical vacuum cavity, and the electron beam emitted by the electron gun moves linearly towards the net. The electron injection gun inside the net is installed at the connection between the cathode high-voltage introduction support rod and the net. Its components include an electron gun cathode, an electron gun anode, and a low-potential shield. The electron gun anode is located between the electron gun cathode and the low-potential shield, with the low-potential shield located on the outermost side. The cathode potential of the electron gun is higher than the potential of the cathode net. The electron gun anode potential is higher than the electron gun cathode potential. The low-potential shield potential is higher than the electron gun cathode potential but lower than the electron gun anode potential.

2. The electron-injection-neutralized inertial electrostatic confinement fusion device as described in claim 1, characterized in that: The electrons emitted from the electron injection gun inside the net move toward the center of the net.

3. The electron-injection-neutralized inertial electrostatic confinement fusion device as described in claim 1, characterized in that: The closest distance between the trajectory of the electrons emitted from the electron injection gun inside the net and the center of the net is 1 cm.

Images