Hall thruster and regulation and control method of Hall thruster

Abstract

The invention discloses a Hall thruster and a Hall thruster regulation and control method, and relates to the technical field of power devices, and the Hall thruster comprises a hollow cathode and a Hall accelerator. The hollow cathode is used for emitting electrons, the Hall accelerator comprises an anode, a first magnet exciting coil, a second magnet exciting coil, a discharge channel and a regulation coil, the first magnet exciting coil and the second magnet exciting coil are used for generating a first magnetic field, and the first magnetic field is at least distributed in a discharge area defined by the discharge channel; the anode is used for attracting electrons emitted by the hollow cathode into a magnetic field of a discharge area for ionization and generating discharge current, and under the condition that the oscillation amplitude of the discharge current is not lower than the target amplitude, the regulation and control coil is used for generating a second magnetic field which is used for adjusting magnetic field distribution in the discharge area. The oscillation amplitude of the discharge current is lower than the target amplitude, and the excitation power supplies of the excitation coil and the regulation coil are different. The Hall thruster has a good low-frequency oscillation suppression effect.

Description

Technical Field

[0001] The present application relates to the technical field of power devices, and particularly to a Hall thruster and a control method thereof. Background Art

[0002] Compared with other types of thrusters (such as cold gas thrusters and chemical thrusters), Hall thrusters have comprehensive advantages in terms of cost and performance, and are widely used in various spacecrafts and are used to perform important tasks such as orbit transfer, position keeping, and terminal reentry.

[0003] Low-frequency oscillation is a common plasma instability phenomenon in the discharge process of Hall thrusters, usually manifested as a significant oscillation in the current amplitude of the discharge current within the frequency range of 10 - 100 kHz. Since the oscillation amplitude of the discharge current can be higher than 10% - 200% of the current average value, there is a risk of damage to circuit components. Therefore, it is necessary to suppress the low-frequency oscillation of Hall thrusters. Summary of the Invention

[0004] The present application provides a Hall thruster and a control method thereof to at least solve the problem of low-frequency oscillation of Hall thrusters.

[0005] The present application provides a Hall thruster, which includes: A hollow cathode for emitting electrons; A Hall accelerator, including an anode, a first excitation coil, a second excitation coil, a discharge channel, and a control coil. The first excitation coil and the second excitation coil are used to generate a first magnetic field, and the first magnetic field is at least distributed in the discharge area surrounded by the discharge channel. The anode is used to attract the electrons emitted by the hollow cathode into the magnetic field of the discharge area for ionization and generate a discharge current. Wherein, when the oscillation amplitude of the discharge current is not lower than the target amplitude, the control coil is used to generate a second magnetic field, and the second magnetic field is used to adjust the magnetic field distribution in the discharge area so that the oscillation amplitude of the discharge current is lower than the target amplitude. The excitation coil and the control coil are deployed in a non-series manner, and the excitation power supplies of the excitation coil and the control coil are different.

[0006] The present application provides a control method for the above Hall thruster, and the method includes: Obtain the first average discharge current and the first peak-to-peak discharge current of the Hall thruster, where the first peak-to-peak discharge current is the difference between the highest amplitude and the lowest amplitude of the first discharge current of the Hall thruster; Based on the first peak-to-peak discharge current and the first average discharge current, determine whether the oscillation amplitude of the discharge current of the Hall thruster is lower than the target amplitude; If the oscillation amplitude of the discharge current is not lower than the target amplitude, the regulation coil of the Hall thruster is excited to adjust the magnetic field distribution in the discharge region of the Hall thruster. When the magnetic field distribution in the discharge region changes, the discharge current of the Hall thruster changes.

[0007] In the technical solutions of some embodiments of the present application, a first excitation coil and a second excitation coil are arranged in the Hall thruster, and the first magnetic field generated by the first excitation coil and the second excitation coil can be distributed at least in the discharge region. In this way, the ionization process of the Hall thruster can be ensured to proceed normally, so that the Hall thruster generates thrust. At the same time, a regulation coil is arranged in the Hall thruster. When the Hall thruster has low-frequency oscillation, a second magnetic field can be generated by the regulation coil to adjust the magnetic field distribution in the discharge region, and then the electron behavior in the Hall thruster can be adjusted, effectively suppressing the low-frequency oscillation of the Hall thruster. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] To more clearly illustrate the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained according to these drawings.

[0009] Figure 1 Schematic diagram of the Hall thruster provided for some embodiments of the present application; Figure 2 For Figure 1 Magnetic field guiding schematic diagram of the Hall thruster in Figure 3 Schematic diagram of the Hall thruster provided for another embodiment of the present application; Figure 4 Flow chart of the regulation method provided for some embodiments of the present application; Figure 5 Schematic diagram of the magnetic field distribution in the discharge region under the rated operating conditions of the Hall thruster provided for some embodiments of the present application; Figure 6 Schematic diagram of the magnetic field distribution in the discharge region after the first regulation provided for some embodiments of the present application; Figure 7 Schematic diagram of the magnetic field distribution in the discharge region after the second regulation provided for some embodiments of the present application; Figure 8 For Figure 5 Discharge current schematic diagram of the Hall thruster in Figure 9 For Figure 6 Discharge current schematic diagram of the Hall thruster in Figure 10 For Figure 7 the schematic diagram of the discharge current of the Hall thruster in Specific embodiments

[0010] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Apparently, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

[0011] It should be noted that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be construed as a limitation of the present application. The terms "installation", "connection", and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the internal communication of two elements. The terms "parallel", "perpendicular", and "equal" include the described situations and situations similar to the described situations, and the range of the similar situations is within the acceptable deviation range, where the acceptable deviation range is determined by those of ordinary skill in the art considering the measurement being discussed and the errors associated with the measurement of a specific quantity (i.e., the limitations of the measurement system). For example, "parallel" includes absolute parallel and approximate parallel, where the acceptable deviation range of approximate parallel can be, for example, within 5° deviation; "perpendicular" includes absolute perpendicular and approximate perpendicular, where the acceptable deviation range of approximate perpendicular can also be, for example, within 5° deviation. "Equal" includes absolute equality and approximate equality, where the acceptable deviation range of approximate equality can be, for example, that the difference between the two equal ones is less than or equal to 5% of either of them. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood in specific situations.

[0012] In some technologies, the methods for suppressing the low-frequency oscillation of Hall thrusters mainly include the active control method and the passive control method. Among them, the active control method mainly controls the discharge parameters of Hall thrusters, such as discharge voltage, discharge current, excitation current, etc., to achieve active suppression of low-frequency oscillation. The passive control method mainly controls the discharge channel size, material, structure, etc. of Hall thrusters to achieve passive suppression of low-frequency oscillation. The active control method has a high adjustment flexibility, but generally is accompanied by a large change in the operating state, that is, during the suppression process of low-frequency oscillation, it cannot ensure that the operating state of the Hall thruster is within the predetermined range, and cannot ensure the effective suppression of low-frequency oscillation. The passive control method mainly realizes the low-frequency oscillation of the Hall thruster through hardware-related designs, usually a one-time design, without flexible adjustability.

[0013] In view of this, the present application provides a Hall thruster, which can effectively suppress the low-frequency oscillation of the Hall thruster. At the same time, it has a high adjustment flexibility and has little impact on the operating state of the Hall thruster.

[0014] Referring to Figure 1 , it is a schematic diagram of the Hall thruster 100 provided by some embodiments of the present application. Figure 1 In , the Hall thruster 100 includes a hollow cathode 101 and a Hall accelerator 102.

[0015] The hollow cathode 101 is used to emit electrons. Specifically, the hollow cathode 101 may include a keeper 11, an emitter 12, a heater 13, and a cathode tube 14. Among them, the cathode tube 14 is a variable-diameter hollow structure, and this hollow structure can be used as a gas (such as xenon, krypton, etc.) flow channel. And an emitter 12 is arranged in the large-diameter hollow structure. After the heater 13 is excited, the emitter 12 can be heated. When the temperature of the emitter 12 reaches the electron emission temperature, initial electrons can be emitted. At this time, after filling the gas in the hollow structure of the cathode tube 14 and exciting the keeper 11, primary discharge can first occur in the keeper 11 and the end slit region of the cathode tube 14 to generate plasma. Subsequently, the plasma in the end slit region can migrate to the hollow region of the emitter 12, and in the hollow region, the continuous operation of the plasma can be maintained through electron bombardment or ion bombardment, etc., and a self-consistent plasma potential drop can be generated between the emitter 12 and the keeper 11 to form the discharge of the hollow cathode 101. After the discharge of the hollow cathode 101 is formed, the keeper 11 can lead out the electrons in the hollow region of the emitter 12 to the outside of the hollow cathode 101, so as to achieve the purpose of the hollow cathode 101 emitting electrons.

[0016] The Hall accelerator 102 includes an anode 5, a first excitation coil 8, a second excitation coil 9, a discharge channel 4, and a regulation coil 10. The discharge channel 4 can enclose a discharge region 15. After the first excitation coil 8 and the second excitation coil 9 are energized, a first magnetic field can be generated. The first magnetic field is at least distributed in the discharge region 15 enclosed by the discharge channel 4.

[0017] Specifically, in this embodiment, the Hall thruster 100 further includes a first magnetic pole 1, a second magnetic pole 2, a magnetic conductive bottom plate 3, a first magnetic shield 6, and a second magnetic shield 7. After the first excitation coil 8 and the second excitation coil 9 are excited by an excitation power supply, currents can be generated in the first excitation coil 8 and the second excitation coil 9, and thus the first excitation coil 8 and the second excitation coil 9 can generate a first magnetic field. The first magnetic pole 1, the second magnetic pole 2, the magnetic conductive bottom plate 3, the discharge channel 4, the first magnetic shield 6, and the second magnetic shield 7 can be used as magnetic circuit construction components. After the first magnetic field generated by the first excitation coil 8 and the second excitation coil 9 is guided by the first magnetic pole 1, the second magnetic pole 2, the discharge channel 4, the first magnetic shield 6, the second magnetic shield 7, and the magnetic conductive bottom plate 3, it is at least distributed in the discharge region 15 enclosed by the discharge channel 4 and forms a closed path of the magnetic field (i.e., a magnetic circuit).

[0018] For easy understanding, refer to Figure 2 , which is Figure 1 a schematic diagram of the magnetic field guidance of the Hall thruster 100 in

[0019] Similarly, after the first excitation coil 8 is energized, a first magnetic field can be generated around the first magnetic pole 1 and in the discharge region 15. The first magnetic field around the first magnetic pole 1 will pass through the discharge channel 4 and reach the second magnetic pole 2 after being guided by the magnetic conductive bottom plate 3, and then reach the first magnetic pole 1 from the second magnetic pole 2.

[0020] It should be noted that the excitation directions of the first excitation coil 8 and the second excitation coil 9 can be the same or opposite. Herein, the excitation direction refers to the magnetic field direction. If the current directions of the first excitation coil 8 and the second excitation coil 9 are the same, it can be considered that the excitation directions of the first excitation coil 8 and the second excitation coil 9 are the same; if the current directions of the first excitation coil 8 and the second excitation coil 9 are opposite, it can be considered that the excitation directions of the first excitation coil 8 and the second excitation coil 9 are opposite. The excitation directions of the first excitation coil 8 and the second excitation coil 9 can be designed according to actual requirements, and the present application does not limit this.

[0021] After being guided by the magnetic circuit construction component, a radially magnetic field distribution with a negative gradient can be formed in the axial direction AB of the discharge region 15. The anode 5 is used to attract the electrons emitted by the hollow cathode 101 into the magnetic field of the discharge region 15 for ionization and generate a discharge current. Specifically, on the one hand, the anode 5 can serve as the high-potential end of the discharge region 15 to attract the electrons emitted by the hollow cathode 101 to move along the anode 5. At the end CD of the discharge region 15 (i.e., the outlet of the discharge region 15), the electrons can be captured by the magnetic field in the discharge region 15 and thus enter the discharge region 15. On the other hand, the anode 5 can serve as a gas distributor to fill the discharge region 15 with gas (such as xenon, krypton, etc.). The gas in the discharge region 15 can collide with the electrons whose energy exceeds the gas ionization energy to generate plasma, and this process is ionization. During the ionization process, due to the energy loss of electrons, a positive-gradient electric field will be formed in the axial direction AB of the discharge region 15, that is, the farther away from the anode 5, the stronger the electric field intensity. The positive-gradient electric field can be used to accelerate and eject the ions generated by ionization from the end CD of the discharge region 15, thereby generating thrust, and at the same time, generating a discharge current. Generally, the magnitude of the discharge current directly affects the ionization rate and intensity. When the discharge current increases, it means that more electrons are accelerated and participate in the ionization process, so that more ions can be generated. These ions are accelerated and ejected from the end CD of the discharge region 15 under the action of the electric field to generate thrust. Therefore, to a certain extent, the increase in the discharge current can increase the thrust of the Hall thruster 100. However, when the discharge current increases to a certain extent, ionization will tend to saturate, and at this time, the increase in the discharge current will no longer increase the thrust of the Hall thruster 100.

[0022] Based on the above relevant descriptions, it can be known that in the frequency range of 10 - 100 kHz, the current amplitude of the discharge current may exhibit significant oscillations (i.e., low-frequency oscillations), which poses a risk of damage to the circuit components of the Hall thruster 100. Therefore, it is necessary to suppress the low-frequency oscillations of the Hall thruster 100. Specifically, the low-frequency oscillations of the Hall thruster 100 are mainly caused by the ionization and replenishment processes of the gas in the ionization region and follow the following expressions (1) and (2).

[0023]

[0024]

[0025] Among them, is the ion velocity, is the neutral particle velocity, is the ion density, is the neutral particle density, is the ionization rate (related to the ionization cross-section and the electron velocity), is the length of the ionization region.

[0026] After combining the above expressions (1) and (2), expression (3) is obtained.

[0027]

[0028] It can be seen that expression (3) is the second-order harmonic oscillator formula. Among them, can be regarded as in the second-order harmonic oscillator formula, represents the average ion density in the ionization region when the Hall thruster 100 does not undergo low-frequency oscillation, represents the average neutral particle density in the ionization region when the Hall thruster 100 does not undergo low-frequency oscillation.

[0029] Based on expression (3), the low-frequency oscillation frequency of the Hall thruster 100 can be as shown in expression (4).

[0030]

[0031] Based on expression (4), it can be known that both the frequency and amplitude of the low-frequency oscillation of the Hall thruster 100 are related to the ionization rate . Among them, the ionization rate is also as shown in expression (5).

[0032]

[0033] Among them, is the ionization cross-section, is the electron velocity. Thus, controlling the electron behavior in the Hall thruster 100, such as controlling the electron velocity in the Hall thruster 100, can effectively suppress the low-frequency oscillation of the Hall thruster 100. And the electron behavior in the Hall thruster 100 can be controlled by the magnetic field distribution in the discharge region 15.

[0034] Based on the above description, when the oscillation amplitude of the discharge current in the Hall thruster 100 is not lower than the target amplitude, the regulation coil 10 can be used to generate a second magnetic field, and the second magnetic field is used to adjust the magnetic field distribution in the discharge region 15 so that the oscillation amplitude of the discharge current is lower than the target amplitude (i.e., suppress the low-frequency oscillation of the discharge current). Specifically, the second magnetic field can also be at least distributed in the discharge region 15. The first magnetic field and the second magnetic field in the discharge region 15 interact with each other, and the magnetic field distribution in the discharge region 15 can be adjusted. When the magnetic field distribution in the discharge region 15 changes, the electron behavior (such as electron velocity) in the Hall thruster 100 can change, thereby effectively suppressing the low-frequency oscillation of the Hall thruster 100.

[0035] In this embodiment, the exciting coils 8, 9 and the regulation coil 10 are deployed in a non-series manner, and the exciting power supplies of the exciting coils 8, 9 and the regulation coil 10 are different. For example, the exciting coils 8, 9 can be excited by a first power supply, and the regulation coil 10 can be excited by a second power supply. In this way, the first magnetic field generated by the exciting coils 8, 9 and the second magnetic field generated by the regulation coil 10 can be controlled separately, and thus the adjustment flexibility can be improved. For example, the current direction of the exciting coils 8, 9 can be opposite to the current direction of the regulation coil 10, so that the exciting direction of the exciting coils 8, 9 is opposite to the exciting direction of the regulation coil 10. On the contrary, if the exciting coils 8, 9 and the regulation coil 10 are deployed in series, the current direction of the exciting coils 8, 9 needs to be the same as the current direction of the regulation coil 10. In this way, the exciting direction of the exciting coils 8, 9 needs to be the same as the exciting direction of the regulation coil 10, which is not convenient for flexibly adjusting the magnetic field distribution in the discharge region 15 according to actual needs.

[0036] In summary, in the technical solutions of some embodiments of the present application, the first exciting coil 8 and the second exciting coil 9 are provided in the Hall thruster 100, and the first magnetic field generated by the first exciting coil 8 and the second exciting coil 9 can be at least distributed in the discharge region 15. In this way, the ionization process of the Hall thruster 100 can be ensured to proceed normally, and the Hall thruster 100 can generate thrust. At the same time, the regulation coil 10 is provided in the Hall thruster 100. When the Hall thruster 100 has a low-frequency oscillation, the second magnetic field can be generated by the regulation coil 10 to adjust the magnetic field distribution in the discharge region 15, and then the electron behavior in the Hall thruster 100 can be adjusted, effectively suppressing the low-frequency oscillation of the Hall thruster 100.

[0037] Compared with the active control method and the passive control method for suppressing low-frequency oscillation in some technologies, the method of the present application can adjust the magnetic field distribution in the discharge region 15 according to actual needs, has a high adjustment flexibility, and has a small impact on the operating state of the Hall thruster.

[0038] In some embodiments, the Hall thruster 100 may include only one regulation coil 10. One of the first excitation coil 8 and the second excitation coil 9 is coaxial with the regulation coil 10. For example, Figure 1 in Figure 1 , the regulation coil 10 is coaxial with the first excitation coil 8. Of course, it can be understood that the regulation coil 10 can also be coaxial with the second excitation coil 9. This application does not limit this. The coaxial deployment method can ensure that the second magnetic field generated by the regulation coil 10 can more effectively and accurately adjust the magnetic field distribution in the discharge region 15.

[0039] In other embodiments, the regulation coil 10 may include a first regulation coil and a second regulation coil. The first excitation coil 8 may be coaxial with the first regulation coil, and the second excitation coil 9 may be coaxial with the second regulation coil. In this way, the second magnetic field generated by the first regulation coil can be mainly used to adjust the magnetic field distribution of the first magnetic field generated by the first excitation coil 8, and the second magnetic field generated by the second regulation coil can be mainly used to adjust the magnetic field distribution of the first magnetic field generated by the first excitation coil 9. Adjusting the magnetic field distribution in the discharge region 15 by at least two regulation coils has a better effect and a more flexible adjustment method.

[0040] Furthermore, the excitation power supplies of the first regulation coil and the second regulation coil are different. In this way, the second magnetic fields generated by the first regulation coil and the second regulation coil can be separately controlled, thereby improving the adjustment flexibility.

[0041] In some embodiments, for the target excitation coil and the target regulation coil that are coaxial, the target regulation coil may be located radially outside the target excitation coil, or the target excitation coil may be located radially outside the target regulation coil. When the target regulation coil is located radially outside the target excitation coil, the radius of the target regulation coil is greater than the radius of the target excitation coil; when the target excitation coil is located radially outside the target regulation coil, the radius of the target excitation coil is greater than the radius of the target regulation coil. For example Figure 1 in Figure 1 , that is, the target regulation coil is located radially outside the target excitation coil. The principle of the target excitation coil being located radially outside the target regulation coil is opposite to that of the target regulation coil being located radially outside the target excitation coil, and will not be elaborated here.

[0042] In other embodiments, in the axial direction of the target excitation coil and the target regulation coil, the target regulation coil is located on one side of the target excitation coil. For easy understanding, refer to Figure 3, A schematic diagram of the Hall thruster 200 provided for another embodiment of the present application. The principle of the Hall thruster 200 is basically similar to that of the Hall thruster 100. The main difference is that the regulation coil 20 (i.e., the target regulation coil) is coaxial with the first excitation coil 28 (i.e., the target excitation coil), and the regulation coil 20 is located on one side of the first excitation coil 28.

[0043] In specific implementation, one of the above deployment methods can be selected according to requirements to deploy the target excitation coil and the target regulation coil, and the present application does not limit this.

[0044] Correspondingly, the present application also provides a regulation method for the above Hall thruster 100 or Hall thruster 200. Referring to Figure 4 , A schematic flow chart of the regulation method provided for some embodiments of the present application. Figure 4 In, the regulation method includes the following steps: Step S401, obtain the average value of the first discharge current and the peak-to-peak value of the first discharge current of the Hall thruster.

[0045] Specifically, the peak-to-peak value of the first discharge current is the difference between the highest amplitude and the lowest amplitude of the first discharge current of the Hall thruster. The discharge current of the Hall thruster at multiple time points within the most recent preset time period can be obtained. Based on the discharge currents at these multiple time points, the average value of the first discharge current and the peak-to-peak value of the first discharge current of the Hall thruster within the most recent preset time period are obtained. For example, obtain the discharge currents of the Hall thruster at multiple time points within the most recent 5 milliseconds. By averaging the discharge currents at these multiple time points, the average value of the first discharge current can be obtained. Among the discharge currents at these multiple time points, the difference between the adjacent highest amplitude and the lowest amplitude can be used as the peak-to-peak value of the first discharge current.

[0046] Step S402, based on the peak-to-peak value of the first discharge current and the average value of the first discharge current, determine whether the oscillation amplitude of the discharge current of the Hall thruster is lower than the target amplitude.

[0047] In this embodiment, the average value of the first discharge current can be multiplied by a first preset ratio to obtain a first reference current value. If the difference between the peak-to-peak value of the first discharge current and the average value of the first discharge current is greater than the first reference current value, it is determined that the oscillation amplitude of the discharge current of the Hall thruster is not lower than the target amplitude. For example, the first preset ratio can be 80%. Suppose the average value of the first discharge current is 0.5 A and the peak-to-peak value of the first discharge current is 1.2 A. 0.5 can be multiplied by 80% to obtain the first reference current value of 0.4. The difference between the peak-to-peak value of the first discharge current and the average value of the first discharge current is 1.2 - 0.5, that is, 0.7. Since 0.7 is greater than the first reference current value of 0.4, it can be determined that the oscillation amplitude of the discharge current of the Hall thruster is not lower than the target amplitude. On the contrary, if the peak-to-peak value of the first discharge current is 0.7 A. The difference between the peak-to-peak value of the first discharge current and the average value of the first discharge current is 0.7 - 0.5, that is, 0.2. Since 0.2 is not greater than the first reference current value of 0.4, it can be determined that the oscillation amplitude of the discharge current of the Hall thruster is lower than the target amplitude.

[0048] Of course, the method for determining the reference current value is not limited to the above method. For example, a difference threshold (such as 0.6) can be set. If the difference between the peak-to-peak value of the first discharge current and the average value of the first discharge current is greater than the difference threshold, it can be determined that the oscillation amplitude of the discharge current of the Hall thruster is not lower than the target amplitude.

[0049] In the above embodiment, generating the first reference current value dynamically according to the average value of the first discharge current can improve the judgment accuracy.

[0050] Step S403, if the oscillation amplitude of the discharge current is not lower than the target amplitude, the regulation coil of the Hall thruster is excited to adjust the magnetic field distribution in the discharge area of the Hall thruster. When the magnetic field distribution in the discharge area changes, the discharge current of the Hall thruster changes.

[0051] Specifically, the peak-to-peak value of the first discharge current can be multiplied by a second preset ratio to obtain a second current reference value. According to the second current reference value, the excitation voltage of the regulation coil is determined, and the regulation coil is excited according to the excitation voltage. For example, the second preset ratio can be 20%. Suppose the peak-to-peak value of the first discharge current is 1 A. After multiplying the peak-to-peak value of the first discharge current by the second preset ratio, the obtained second current reference value is 0.2 A. Based on the second current reference value of 0.2 A, the excitation voltage of the regulation coil can be controlled so that the regulation coil generates a current of 0.2 A.

[0052] Determining the excitation voltage of the regulation coil according to the peak-to-peak value of the first discharge current can effectively adjust the magnetic field distribution in the discharge area.

[0053] In some embodiments, after exciting the regulation coil according to the second current reference value, the method of the present application may further include: Obtain the average value of the second discharge current and the peak-to-peak value of the second discharge current of the Hall thruster, where the peak-to-peak value of the second discharge current is the difference between the highest amplitude and the lowest amplitude of the second discharge current of the Hall thruster; If the peak-to-peak value of the second discharge current is less than the peak-to-peak value of the first discharge current, multiply the average value of the second discharge current by a third preset ratio to obtain a third current reference value; If the difference between the peak-to-peak value of the second discharge current and the average value of the second discharge current is greater than the third current reference value, continue to adjust the excitation voltage of the regulation coil; If the difference between the peak-to-peak value of the second discharge current and the average value of the second discharge current is not greater than the third current reference value, stop adjusting the excitation voltage of the regulation coil.

[0054] Among them, obtaining the average value of the second discharge current and the peak-to-peak value of the second discharge current is similar to the principle of obtaining the average value of the first discharge current and the peak-to-peak value of the first discharge current, and will not be elaborated here.

[0055] For example, the third preset ratio can be 50%. Assume that the average value of the second discharge current is 0.4 A and the peak-to-peak value of the first discharge current is 0.7 A. After multiplying the average value of the second discharge current by the third preset ratio, a third current reference value of 0.2 A is obtained. The difference between the peak-to-peak value of the second discharge current and the average value of the second discharge current is 0.7 - 0.4, that is, 0.3. Since 0.3 is greater than the third current reference value of 0.2 A, therefore, the excitation voltage of the regulation coil can be continuously adjusted based on the peak-to-peak value of the second discharge current and the second preset ratio, and this process is similar to adjusting the excitation voltage of the regulation coil based on the peak-to-peak value of the first discharge current and the second preset ratio, which will not be elaborated here. Conversely, assume that the average value of the second discharge current is 0.4 A and the peak-to-peak value of the first discharge current is 0.45 A. When the third preset ratio is 50%, since the difference between the peak-to-peak value of the second discharge current and the average value of the second discharge current is 0.45 - 0.4, that is, 0.05. Since 0.05 is less than the third current reference value of 0.2 A. At this time, it indicates that the low-frequency oscillation of the Hall thruster has been effectively suppressed, so the excitation voltage of the regulation coil can be stopped from being adjusted.

[0056] In some embodiments, if the peak-to-peak value of the second discharge current is greater than the peak-to-peak value of the first discharge current, it means that during the regulation process, the current direction of the regulation coil is incorrect, which enhances the low-frequency oscillation of the Hall thruster. At this time, the current direction of the regulation coil can be changed.

[0057] Refer to in combination Figures 5 to 7 . Figure 5Schematic diagram of the magnetic field distribution in the discharge region under the rated operating conditions of the Hall thruster provided by some embodiments of the present application. Figure 6 Schematic diagram of the magnetic field distribution in the discharge region after the first regulation provided by some embodiments of the present application. Figure 7 Schematic diagram of the magnetic field distribution in the discharge region after the second regulation provided by some embodiments of the present application. It can be seen that Figures 5 to 7 the magnetic field distribution in the discharge region is gradually changing.

[0058] Refer to Figures 8 to 10 . Figure 8 is Figure 5 the schematic diagram of the discharge current of the Hall thruster in Figure 9 is Figure 6 the schematic diagram of the discharge current of the Hall thruster in Figure 10 is Figure 7 the schematic diagram of the discharge current of the Hall thruster in Figures 8 to 10 It can be seen that after multiple regulations, the low-frequency oscillation of the Hall thruster has been effectively suppressed.

[0059] The above has introduced in detail the Hall thruster and the regulation method of the Hall thruster provided by the present application. Specific examples are used in this article to elaborate on the principle and implementation manner of the present application. The description of the above embodiments is only used to help understand the method and its core idea of the present application. It should be noted that for those of ordinary skill in the art in this technical field, without departing from the principle of the present application, several improvements and modifications can still be made to the present application, and these improvements and modifications also fall within the protection scope of the claims of the present application.

Claims

1. A Hall thruster, characterized in that The Hall thruster includes: A hollow cathode for emitting electrons; A Hall accelerator, including an anode, a first excitation coil, a second excitation coil, a discharge channel, and a regulation coil. The first excitation coil and the second excitation coil are used to generate a first magnetic field, and the first magnetic field is at least distributed in the discharge area surrounded by the discharge channel. The anode is used to attract the electrons emitted by the hollow cathode into the magnetic field of the discharge area for ionization and generate a discharge current. Among them, when the oscillation amplitude of the discharge current is not lower than the target amplitude, the regulation coil is used to generate a second magnetic field, and the second magnetic field is used to adjust the magnetic field distribution in the discharge area so that the oscillation amplitude of the discharge current is lower than the target amplitude. The excitation coil and the regulation coil are deployed in a non-series manner, and the excitation power supplies of the excitation coil and the regulation coil are different.

2. The Hall thruster according to claim 1, wherein One of the first excitation coil and the second excitation coil is coaxial with the regulation coil.

3. The Hall thruster according to claim 1, characterized in that, The regulation coil includes a first regulation coil and a second regulation coil. The first excitation coil is coaxial with the first regulation coil, and the second excitation coil is coaxial with the second regulation coil.

4. The Hall thruster according to claim 2 or 3, characterized in that For the target excitation coil and the target regulation coil that are coaxial, the deployment method between the target excitation coil and the target regulation coil is one of the following methods: The target regulation coil is located radially outside the target excitation coil, and the radius of the target regulation coil is greater than the radius of the target excitation coil; The target excitation coil is located radially outside the target regulation coil, and the radius of the target excitation coil is greater than the radius of the target regulation coil; In the axial direction of the axes of the target excitation coil and the target regulation coil, the target regulation coil is located on one side of the target excitation coil.

5. The Hall thruster according to claim 2 or 3, characterized in that, The Hall thruster further includes a first magnetic pole, a second magnetic pole, a magnetic conduction bottom plate, a first magnetic screen, and a second magnetic screen. After being guided by the first magnetic pole, the second magnetic pole, the discharge channel, the first magnetic screen, the second magnetic screen, and the magnetic conduction bottom plate, the first magnetic field generated by the first excitation coil and the second excitation coil is at least distributed in the discharge area surrounded by the discharge channel.

6. A control method for the Hall thruster according to any one of claims 1 to 5, characterized in that The method includes: Obtaining the average value of the first discharge current and the peak-to-peak value of the first discharge current of the Hall thruster. The peak-to-peak value of the first discharge current is the difference between the highest amplitude and the lowest amplitude of the first discharge current of the Hall thruster; Based on the peak-to-peak value of the first discharge current and the average value of the first discharge current, determining whether the oscillation amplitude of the discharge current of the Hall thruster is lower than the target amplitude; If the oscillation amplitude of the discharge current is not lower than the target amplitude, then excite the regulation coil of the Hall thruster to adjust the magnetic field distribution in the discharge area of the Hall thruster. Among them, when the magnetic field distribution in the discharge area changes, the discharge current of the Hall thruster changes.

7. The method according to claim 6, characterized in that, The determining whether the oscillation amplitude of the discharge current of the Hall thruster is lower than the target amplitude based on the peak-to-peak value of the first discharge current and the average value of the first discharge current includes: Multiply the average value of the first discharge current by a first preset ratio to obtain a first reference current value; If the difference between the peak-to-peak value of the first discharge current and the average value of the first discharge current is greater than the first reference current value, it is determined that the oscillation amplitude of the discharge current of the Hall thruster is not lower than the target amplitude.

8. The method according to claim 6, wherein The regulating coil for exciting the Hall thruster includes: Multiply the peak-to-peak value of the first discharge current by a second preset ratio to obtain a second current reference value; Determine the excitation voltage of the regulating coil according to the second current reference value, and excite the regulating coil according to the excitation voltage.

9. The method according to claim 8, characterized in that After exciting the regulating coil according to the second current reference value, the method further includes: Obtain the average value of the second discharge current and the peak-to-peak value of the second discharge current of the Hall thruster, where the peak-to-peak value of the second discharge current is the difference between the highest amplitude and the lowest amplitude of the second discharge current of the Hall thruster; If the peak-to-peak value of the second discharge current is less than the peak-to-peak value of the first discharge current, multiply the average value of the second discharge current by a third preset ratio to obtain a third current reference value; If the difference between the peak-to-peak value of the second discharge current and the average value of the second discharge current is greater than the third current reference value, continue to adjust the excitation voltage of the regulating coil; If the difference between the peak-to-peak value of the second discharge current and the average value of the second discharge current is not greater than the third current reference value, stop adjusting the excitation voltage of the regulating coil.

10. The method according to claim 9, characterized in that, The method further includes: If the peak-to-peak value of the second discharge current is greater than the peak-to-peak value of the first discharge current, change the current direction of the regulating coil.

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