Method, system, medium and device for determining top hole size of large-current wide-regulation hollow cathode

Abstract

This invention provides a method, system, medium, and device for determining the top hole size of a high-current, wide-range adjustable hollow cathode, belonging to the field of aerospace propulsion technology. It establishes a mathematical relationship between the diameter and length ratio of the cathode top hole. Step S1: Determine the operating current range of the hollow cathode; Step S2: Calculate the minimum current operating point I. l The corresponding optimal cathode top hole diameter D l Step S3: Calculate the maximum current operating point I h The corresponding optimal cathode top hole diameter D h Step S4: Based on the minimum current operating point I l The corresponding optimal cathode top hole diameter D l Maximum current operating point I h The corresponding optimal cathode top hole diameter D h Optimal cathode top hole diameter D c and length L c The correlation determines the optimal cathode top hole diameter D. c and length L c This invention provides a design basis for optimizing the performance of high-current, wide-adjustment hollow cathodes.

Description

Technical Field

[0001] This invention relates to the field of aerospace propulsion technology, specifically to a method, system, medium, and equipment for determining the top hole size of a high-current, wide-adjustment hollow cathode. Background Technology

[0002] A hollow cathode is a discharge device that uses thermionic emission technology to provide an electron beam, commonly used as an igniter or neutralizer in Hall effect electric propulsion or ion electric propulsion. Hollow cathodes with high current (>100A) and wide turn-by-turn ratios are widely used in high-power electric propulsion, especially for multi-mode missions, and are currently a key research direction in high-power electric propulsion. However, under current technology, high-current, wide-turn-by-turn hollow cathodes cannot maintain high performance in a single operating mode (point-like) across all current operating points, leading to a significant bottleneck in the engineering development of this type of hollow cathode, which is one of the major problems that researchers urgently need to solve.

[0003] Regarding the design methods for hollow cathodes, researchers mainly focus on the size and structure design of the cathode top: The published paper "Matthew T D. An Evaluation of Hollow Cathode Scaling to Very Low Power and Flow Rate. IEPC-97-189." provides design formulas for the diameter of the cathode top and the inner cavity diameter of the emitter in relation to the discharge current; the published paper "Matthew T D. Evaluation of Low-Current Orificed Hollow Cathodes. PhD thesis. University of Michigan, 1999" proposes that for low-current hollow cathodes, the cathode top length [mm] should be 1 / 6 of the discharge current, and the reflector's emission area should match the design area corresponding to the Charleson emission current; the published paper "Hani K. Development and Testing of High Current Hollow Cathodes for High Power Hall Thrusters. AIAA-2012-4080" proposes that for 100A-class hollow cathodes, the cathode top aperture size should be appropriately increased, which will lower the emitter temperature and improve cathode performance; the published paper "Kubota K. Numerical and The experimental study on discharge characteristics of high-current hollow cathode (AIAA-2016-4628) proposes that for high-current cathodes (180A class), the cathode top aperture has a more significant impact on performance than the cathode top-contact electrode spacing. It also reveals for the first time that there is an electron beam focusing effect in high-current hollow cathodes, which reduces discharge performance.

[0004] Patent document CN106373842A (application number: 201610959108.2) discloses a method for widening the point-mode discharge current range of a hollow cathode, relating to the technical field of widening the discharge current range of a hollow cathode. This method addresses the problem of a narrow point-mode discharge current range in hollow cathodes, where traditional methods for widening the range reduce the specific impulse of the entire propulsion system and easily cause cathode overheating. The method involves designing cathode components based on the actual requirements of the hollow cathode and initially setting the orifice inward displacement distance; ensuring the cathode operates normally and measuring the hollow cathode's operating parameters; optimizing the orifice inward displacement distance based on the hollow cathode's operating parameters, then ensuring the cathode operates normally again and measuring the hollow cathode's operating parameters; repeating step three until the optimal orifice inward displacement distance is found.

[0005] In summary, there are relatively detailed design methods and strategies for both small and large current hollow cathodes. However, these design methods cannot solve the problem of "the inability to maintain the point mode at all operating points" for large current hollow cathodes with wide adjustment ratios. Therefore, it is necessary to establish a new design method for large current hollow cathodes with wide adjustment ratios to solve this problem. Summary of the Invention

[0006] To address the shortcomings of existing technologies, the purpose of this invention is to provide a method, system, medium, and device for determining the top hole size of a high-current, wide-adjustment hollow cathode.

[0007] A method for determining the top hole size of a high-current, wide-adjustment hollow cathode according to the present invention includes:

[0008] Step S1: Determine the operating current range of the hollow cathode;

[0009] Step S2: Calculate the minimum current operating point I l The corresponding optimal cathode top hole diameter D l ;

[0010] Step S3: Calculate the maximum current operating point I h The corresponding optimal cathode top hole diameter D h ;

[0011] Step S4: Based on the minimum current operating point I l The corresponding optimal cathode top hole diameter D l Maximum current operating point I h The corresponding optimal cathode top hole diameter D h Optimal cathode top hole diameter D c and length L c The correlation determines the optimal cathode top hole diameter D. c and length L c .

[0012] Preferably, step S2 includes:

[0013]

[0014] Preferably, step S3 includes:

[0015]

[0016] Preferably, step S4 includes:

[0017]

[0018] A high-current, wide-adjustment hollow cathode top hole size determination system provided by the present invention includes:

[0019] Module M1: Determines the operating current range of the hollow cathode;

[0020] Module M2: Calculate the minimum current operating point I l The corresponding optimal cathode top hole diameter D l ;

[0021] Module M3: Calculates the maximum current operating point I h The corresponding optimal cathode top hole diameter D h ;

[0022] Module M4: Based on minimum current operating point I l The corresponding optimal cathode top hole diameter D l Maximum current operating point I h The corresponding optimal cathode top hole diameter D h Optimal cathode top hole diameter D c and length L c The correlation determines the optimal cathode top hole diameter D. c and length L c .

[0023] Preferably, the module M2 includes:

[0024]

[0025] Preferably, the module M3 includes:

[0026]

[0027] Preferably, the module M4 includes:

[0028]

[0029] According to an electronic device provided by the present invention, the electronic device includes a memory and at least one processor, wherein the memory stores instructions;

[0030] The at least one processor invokes the instructions in the memory to cause the electronic device to perform the various steps of the high-current wide-adjustment hollow cathode top hole size determination method as described above.

[0031] According to a computer-readable storage medium provided by the present invention, the computer-readable storage medium stores instructions that, when executed by a processor, implement the various steps of the method for determining the top hole size of a high-current wide-adjustment hollow cathode as described above.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] 1. This invention can optimize the design of high-current cathode with fast and efficient wide current regulation performance. The designed hollow cathode current regulation ratio is generally above 1:10, which can meet the requirements of high-power, multi-mode Hall electric propulsion or ion electric propulsion technology for electron emission capability.

[0034] 2. This invention can improve the gas ionization rate under low current and reduce the electron beam focusing effect under high current, so that the hollow cathode can maintain a point-like working mode over a wide range of working currents, thereby improving the wide-range current emission capability of the high-current hollow cathode. Attached Figure Description

[0035] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0036] Figure 1 Flowchart of the method for determining the top hole size of a high-current, wide-range adjustable hollow cathode. Detailed Implementation

[0037] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0038] Example 1

[0039] According to the present invention, a method for determining the top hole size of a high-current, wide-adjustment hollow cathode is provided, such as... Figure 1 As shown, it includes:

[0040] Step 1: Set the operating current range of the hollow cathode;

[0041] Step 2: Calculate the minimum current operating point I l The corresponding optimal cathode top hole diameter D l ;

[0042] Step 3: Calculate the maximum current operating point I h The corresponding optimal cathode top hole diameter D h ;

[0043] Step 4: According to D l D h D c With L c The correlation is used to determine the optimal cathode tip hole diameter D. c and length L c .

[0044] In this embodiment, the operating current range of the hollow cathode is 2 to 200 A.

[0045] In this embodiment, the definition range of the minimum current is 2 to 10 A.

[0046] The minimum current operating point I in step 2 l The corresponding optimal cathode top hole diameter D l The calculation method is as follows:

[0047]

[0048] This formula increases the gas ionization rate in the cathode top region, achieving a convergence effect of neutral gas in the top hole region, to adapt to the discharge state with insufficient gas ionization collision free path under low flow rate and small current.

[0049] In this embodiment, the maximum current is defined as 80–200A.

[0050] The maximum current operating point I in step 3 h The corresponding optimal cathode top hole diameter D h The calculation method is as follows:

[0051]

[0052] This formula increases the aperture of the cathode top hole to reduce the frequency of electron-atom excitation and elastic collisions under high-density background gas, in order to adapt to the discharge state with excessively high gas excitation collision free path under high flow rate and high current, i.e. electron beam focusing effect.

[0053] In this embodiment, D in step 4 l D h D c With L c The correlation is:

[0054]

[0055] This set of formulas increases the diameter of the cathode tip hole while extending the length of the cathode tip, in order to address both the problem of insufficient ionization rate under low current and the problem of electron beam focusing under high current.

[0056] The present invention also provides a system for determining the top hole size of a high-current-width adjustable hollow cathode. The system for determining the top hole size of a high-current-width adjustable hollow cathode can be implemented by executing the process steps of the method for determining the top hole size of a high-current-width adjustable hollow cathode. That is, those skilled in the art can understand the method for determining the top hole size of a high-current-width adjustable hollow cathode as a preferred embodiment of the system for determining the top hole size of a high-current-width adjustable hollow cathode.

[0057] Although the optimal cathode top aperture diameter can be determined based on either the maximum or minimum operating current, using a cathode top aperture design corresponding to a small current can lead to a higher electron beam focusing effect under high current conditions, while using a cathode top aperture design corresponding to a large current can lead to a decrease in ionization rate under low current conditions. Therefore, to balance maintaining the ionization rate and avoiding the electron beam focusing effect over a wide range of operating currents, a strategy of simultaneously increasing the cathode top aperture diameter and extending the cathode top length is proposed. This allows the hollow cathode to operate in a "point-like working mode" with high performance over a wide range of operating currents. All structural modifications, material substitutions, formula transformations, and gaseous working fluid substitutions made within this spirit and principle should be included within the scope of protection of this invention.

[0058] Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. Unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

Claims

1. A method for determining the top hole size of a high-current, wide-range adjustable hollow cathode, characterized in that, include Step S1: Determine the operating current range of the hollow cathode; Step S2: Calculate the minimum current operating point I l The corresponding optimal cathode top hole diameter D l ; Step S3: Calculate the maximum current operating point I h The corresponding optimal cathode top hole diameter D h ; Step S4: Based on the minimum current operating point I l The corresponding optimal cathode top hole diameter D l Maximum current operating point I h The corresponding optimal cathode top hole diameter D h Optimal cathode top hole diameter D c and length L c The correlation determines the optimal cathode top hole diameter. D c and length L c ; Step S2 includes: ； Step S3 includes: ； Step S4 includes: 。 2. A system for determining the top hole size of a high-current, wide-range adjustable hollow cathode, characterized in that: include Module M1: Determines the operating current range of the hollow cathode; Module M2: Calculate the minimum current operating point I l The corresponding optimal cathode top hole diameter D l ; Module M3: Calculate the maximum current operating point I h The corresponding optimal cathode top hole diameter D h ; Module M4: Based on minimum current operating point I l The corresponding optimal cathode top hole diameter D l Maximum current operating point I h The corresponding optimal cathode top hole diameter D h Optimal cathode top hole diameter D c and length L c The correlation determines the optimal cathode top hole diameter. D c and length L c ; The module M2 includes: ； The module M3 includes: ； The module M4 includes: 。 3. An electronic device, the electronic device comprising a memory and at least one processor, the memory storing instructions; The at least one processor invokes the instructions in the memory to cause the electronic device to perform the steps of the method for determining the top hole size of a high-current, wide-adjustable hollow cathode as described in claim 1.

4. A computer-readable storage medium storing instructions thereon, characterized in that, When the instructions are executed by the processor, they implement each step of the method for determining the top hole size of a high-current, wide-range adjustable hollow cathode as described in claim 1.

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