A surface discharge plasma magnetron system

Abstract

The present invention discloses a surface discharge plasma magnetron system, comprising: a plasma generating module for generating plasma; a guide magnetic field generating module, arranged on one side of the plasma generating module, for forming a traveling wave magnetic field that changes cyclically according to a set period, the traveling wave magnetic field comprising at least one traveling wave sub-magnetic field, the traveling wave sub-magnetic field being configured to form an induced current in the plasma within its magnetic control range, and to apply a magnetic thrust to the plasma to cause it to move laterally. The entire traveling wave magnetic field can be divided into at least one traveling wave sub-magnetic field, each traveling wave sub-magnetic field can form an induced current in the plasma within the corresponding magnetic control range, the induced current and the traveling wave sub-magnetic field that changes in time and space are coupled to each other to generate a magnetic thrust, so that the plasma moves in the direction of the set magnetic field change, the plasma just generated by the initial breakdown voltage discharge is diffused in a directional manner, the plasma is evenly distributed through the magnetic field control, and the discharge voltage is reduced.

Description

Technical Field

[0001] The invention relates to the field of plasma technology, and in particular to a surface discharge plasma magnetron system. Background Art

[0002] Surface discharge can be used to generate large-area, highly active plasma. Surface discharge devices can be made into different shapes to adapt to the shape requirements of different treatment objects. Direct electrical contact with the treated objects is avoided, and the treatment flexibility is high. It has unique technical advantages and broad application prospects in the fields of plasma biomedicine, material processing, water treatment, etc.

[0003] However, there are two outstanding problems that need to be solved during the use of surface discharge plasma:

[0004] The first problem is that for surface discharge plasma, as the external applied voltage increases, local discharge will first occur, and the discharge will not be overall uniform until the voltage increases to a certain level. Therefore, in order to achieve uniform and stable discharge of surface discharge plasma, it is necessary to continuously apply extremely high discharge voltage. For surface discharge devices made of insulating media such as polytetrafluoroethylene, ceramics or plexiglass, an excitation voltage of more than 10kV is usually required to achieve uniform surface discharge. High discharge voltage will bring many hidden dangers, such as power consumption, difficulty in plasma control, electrical breakdown, spark and arc discharge, etc., and there is a risk of damage to the treated object.

[0005] The second problem is that the mass transfer distance of high-energy active substances generated by surface discharge plasma is too short. Since there is no direct electrical contact between the site where surface discharge occurs and the object to be treated, there is a gap of the order of centimeters. After being produced, the high-energy active substances move and collide irregularly, and the guidance of the high-energy active substances cannot be effectively controlled, resulting in most of the high-energy active substances being unable to pass through the gap to reach the object to be treated, such as high-energy electrons, oxygen negative ions, etc., which greatly reduces the treatment effect and technical advantages of surface discharge plasma. Summary of the invention

[0006] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the purpose of the present invention is to provide a surface discharge plasma magnetron system to solve the problems in the prior art such as the need to use a high discharge voltage to achieve uniform surface discharge and the small diffusion distance of high-energy active substances.

[0007] In order to achieve the above object, the present invention adopts the following technical scheme:

[0008] The present application provides a surface discharge plasma magnetron system, comprising:

[0009] A plasma generating module, used for generating plasma;

[0010] The guide magnetic field generating module is arranged on one side of the plasma generating module, and is used to form a traveling wave magnetic field that changes cyclically according to a set period. The traveling wave magnetic field includes at least one traveling wave sub-magnetic field, and the traveling wave sub-magnetic field is configured to form an induced current in the plasma within its magnetic control range and exert a magnetic thrust on the plasma to cause it to move laterally.

[0011] In some embodiments, the set period includes a forward sub-period and a reverse sub-period, the traveling wave magnetic field in the forward sub-period applies a first direction magnetic thrust to the plasma, and the traveling wave magnetic field in the reverse sub-period applies a second direction magnetic thrust to the plasma, and in the same traveling wave sub-magnetic field, the first direction magnetic thrust and the second direction magnetic thrust applied to the plasma are two opposite direction forces along the same straight line.

[0012] In some embodiments, a plurality of the traveling wave sub-magnetic fields are arranged side by side, and the magnetic thrusts exerted by different traveling wave sub-magnetic fields on the plasma in their respective magnetic control ranges are parallel to each other.

[0013] In some embodiments, a plurality of the traveling wave sub-magnetic fields are evenly distributed around the same center of a circle, and at the same time, the magnetic thrusts exerted by different traveling wave sub-magnetic fields on the plasma in their respective magnetic control ranges are simultaneously directed forwardly or reversely toward the same center of a circle.

[0014] In some embodiments, the guide magnetic field generating module is further used to form a rotating magnetic field, and the rotating magnetic field is configured to form axial magnetic lines perpendicular to the plasma and cause the plasma to perform Larmor cyclotron along the axial magnetic lines.

[0015] In some embodiments, the guide magnetic field generating module includes a magnetic field control unit and at least one magnetic core array, wherein the magnetic core array includes N U-shaped magnetic core units with excitation coils arranged at intervals, wherein N is greater than or equal to 3, and the magnetic field control unit is electrically connected to the excitation coils of each of the magnetic core units respectively;

[0016] The magnetic field control unit is configured to sequentially supply N-phase excitation currents with a phase sequence of 0°, 360° / N, 360°*2 / N…360°*(N-1) / N to the excitation coils of the magnetic core units in the same magnetic core array.

[0017] In some embodiments, the plasma generating module includes a plasma control unit and a dielectric barrier surface discharge component, the dielectric barrier surface discharge component includes a metal layer, an insulating medium layer and a ground electrode layer that are tightly fitted from bottom to top, the metal layer and the ground electrode layer are made of non-magnetic materials, the ground electrode layer includes a plurality of sub-queue electrodes arranged side by side, and electrode gaps are provided between adjacent sub-queue electrodes, and the extension direction of the sub-queue electrodes is consistent with the direction of magnetic thrust in the traveling wave sub-magnetic field to which they belong.

[0018] In some embodiments, a matching gap is provided between the dielectric barrier surface discharge assembly and the magnetic core array, a non-magnetic shielding insulating medium is provided in the matching gap, and the matching gap is 5 to 10 mm.

[0019] In some embodiments, the U-shaped magnetic core unit includes two polarity ends, the width of a single polarity end in the side-by-side direction of the sub-queue electrodes is greater than or equal to the distance between the farthest structural parts of two adjacent sub-queue electrodes in the side-by-side direction, and the minimum distance between the two polarity ends is less than the distance between the closest structural parts of two adjacent sub-queue electrodes in the side-by-side direction.

[0020] In some embodiments, the sub-array electrodes are in a linear shape or a linear grid shape.

[0021] Compared with the prior art, the present invention has at least the following beneficial effects:

[0022] The surface discharge plasma magnetron system provided in the embodiment of the present application forms a traveling wave magnetic field in the space where the plasma generating module is located. The entire traveling wave magnetic field can be divided into at least one traveling wave sub-magnetic field. Each traveling wave sub-magnetic field can form an induced current in the plasma within the corresponding magnetron range. The induced current and the traveling wave sub-magnetic field that changes in time and space are coupled to each other to generate a magnetic thrust, so that the plasma moves in the direction of the set magnetic field change, the plasma just generated by the initial breakdown voltage discharge is diffused in a direction, and the plasma is uniformly distributed by controlling the magnetic field, thereby reducing the discharge voltage;

[0023] By forming a rotating magnetic field in the space where the plasma generating module is located and utilizing the axial magnetic lines of force perpendicular to the plasma in the rotating magnetic field, the charged high-energy active substances in the plasma perform Larmor cyclotron motion around the axial magnetic lines of force under the action of the Lorentz force of the rotating magnetic field, and diffuse spirally upward, thereby effectively increasing the vertical axial propagation distance of the charged particles.

[0024] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The present invention is further described using the accompanying drawings, but the embodiments in the accompanying drawings do not constitute any limitation to the present invention. A person skilled in the art can obtain other drawings based on the following drawings without creative work.

[0026] Figure 1 The present invention is a schematic diagram of the system structure of a surface discharge plasma magnetron system in one embodiment.

[0027] Figure 2 It is a schematic diagram of the structure of a guide magnetic field generating module in one embodiment.

[0028] Figure 3 The present invention is a schematic diagram of the structure of a ground electrode layer in a dielectric barrier surface discharge component in one embodiment.

[0029] Figure 4 yes Figure 1 The illustrated embodiment is a graph showing the change in magnetic field strength over time during application.

[0030] Figure 5 yes Figure 1 A schematic diagram of the change in magnetic field strength value of the illustrated embodiment during application.

[0031] Figure 6 yes Figure 1 A schematic diagram of the self-induced current distribution generated by the illustrated embodiment in application. DETAILED DESCRIPTION

[0032] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention 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 therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0034] In the description of the present invention, when it is described that a specific device is located between a first device and a second device, there may or may not be an intermediate device between the specific device and the first device or the second device. When it is described that a specific device is connected to other devices, the specific device may be directly connected to the other devices without an intermediate device, or may not be directly connected to the other devices but have an intermediate device.

[0035] Technologies, methods, and equipment known to ordinary technicians in the relevant art may not be discussed in detail, but where appropriate, the technologies, methods, and equipment should be considered as part of the specification.

[0036] During the formation of surface discharge plasma, it will first experience local discharge and then uniform discharge. This transformation process requires a continuous increase in the discharge voltage. Because when the local discharge starts, the plasma concentration at this local location is high, and the plasma diffuses very slowly without external force. Therefore, in order to further discharge and ionize, the discharge voltage can only be increased. Only when it increases to a certain level will the overall discharge be uniform, resulting in a large discharge voltage.

[0037] In view of this, refer to Figure 1 , this embodiment provides a surface discharge plasma magnetron system, comprising:

[0038] The plasma generation module generates plasma by surface discharge, and the plasma includes high-energy active substances such as high-energy electrons and oxygen negative ions;

[0039] The guide magnetic field generating module is arranged on one side of the plasma generating module. In the present embodiment, the guide magnetic field generating module is located below the plasma generating module. After the guide magnetic field generating module is supplied with a changing current, a traveling wave magnetic field that changes cyclically according to a set period is formed. The magnetic control range of the traveling wave magnetic field includes the entire plasma generating module. According to the arrangement of the plasma generating module, the traveling wave magnetic field includes at least one traveling wave sub-magnetic field. If the area for generating plasma in the plasma generating module is small, only one traveling wave sub-magnetic field may be arranged. If the area for generating plasma is large, only multiple traveling wave sub-magnetic fields may be arranged. Each traveling wave sub-magnetic field has its own control. The current control method corresponding to each traveling wave sub-magnetic field can be the same or different within the corresponding magnetic control range. Each traveling wave sub-magnetic field is a magnetic field that continuously moves in a specific direction in space. During the movement, the relative configuration of its spatial waveform remains unchanged, but the positions of the nodes and peaks of the moving magnetic field waveform are alternating, which causes the magnetic field to continue to advance in this alternating change. During the time shift of the traveling wave sub-magnetic field, the changing traveling wave sub-magnetic field forms an induced current in the plasma within its magnetic control range. Due to the mutual coupling between the magnetic field and the induction circuit, the magnetic thrust acting on the plasma is directly generated, and the magnetic thrust causes the plasma to move in a specific direction.

[0040] In the above manner, when local discharge occurs in the middle area, the traveling wave magnetic field is used to diffuse the plasma in the middle area to the surrounding areas in an radiating manner; or when local discharge occurs on the side line, the traveling wave magnetic field is used to move the plasma on the left side to the right side. In short, by providing magnetic thrust, each plasma can be evenly dispersed in the early stage of local discharge, which reduces the plasma concentration in the local discharge area, thereby reducing the discharge voltage growth rate and maximum value in this local area, and increases the plasma concentration in other areas, making the distribution of charged particles more uniform, inducing discharge in other areas, and achieving a more overall uniform surface discharge, greatly reducing the discharge voltage.

[0041] In this embodiment, by controlling the size and direction of the current, the overall traveling wave magnetic field is made to circulate according to a certain movement mode and a set period. More specifically, the set period includes a forward sub-period and a reverse sub-period. The traveling wave magnetic field in the forward sub-period applies a first-direction magnetic thrust to the plasma, and the traveling wave magnetic field in the reverse sub-period applies a second-direction magnetic thrust to the plasma. In the same traveling wave sub-magnetic field, the first-direction magnetic thrust and the second-direction magnetic thrust applied to the plasma are two opposite-direction forces along the same straight line. It should be noted that in the forward sub-period, the first-direction magnetic thrust causes the plasma to move to the left, and in the reverse sub-period, the second-direction magnetic thrust causes the plasma to move to the right. Through the bidirectional switching of the magnetic thrust, the plasma is evenly oscillated left and right and evenly dispersed to both sides.

[0042] As an implementation mode, a set cycle may include multiple forward sub-cycles and reverse sub-cycles, and the forward sub-cycles and reverse sub-cycles alternate with each other. Moreover, as time goes by, by controlling the connected control current, the magnetic thrust corresponding to each sub-cycle is controlled to gradually increase. For example, a set cycle includes three forward sub-cycles and three reverse sub-cycles. The magnetic thrust is 5N in the first forward sub-cycle, -5N in the first reverse sub-cycle, 10N in the second forward sub-cycle, -10N in the second reverse sub-cycle, 15N in the third forward sub-cycle, and -15N in the third forward sub-cycle. The intensity of diffusion is increased later. Of course, the diffusion time can also be increased later. According to the shape of the actual plasma generating module, the guiding distance in the specified direction is controlled. Therefore, the range covered by different traveling wave sub-magnetic fields can be determined according to the shape of the plasma generating module. A longer traveling wave sub-magnetic field is set in a longer area, and a shorter traveling wave sub-magnetic field is set in a shorter area, and the diffusion distance is increased by the corresponding magnetic thrust and sub-cycle time.

[0043] As an implementation mode, when the width of the plasma generating module is relatively wide, since the width of a single traveling wave sub-magnetic field is limited, a plurality of traveling wave sub-magnetic fields arranged side by side are provided, and the magnetic thrusts applied by different traveling wave sub-magnetic fields to the plasma in their respective magnetic control ranges are parallel to each other, which is equivalent to the existence of multiple parallel magnetic thrusts on the same plane at the same time, so that the plasma is dispersed and moves uniformly in the same set direction. Of course, by controlling the changing current, the bidirectional reciprocating movement of the plasma can also be controlled.

[0044] As another embodiment, multiple traveling wave sub-magnetic fields are evenly distributed around the same center of a circle, and are evenly distributed in a fan-shaped ring shape. At the same time, the magnetic thrusts applied by different traveling wave sub-magnetic fields to the plasma in their respective magnetic control ranges are simultaneously directed forward to a center of a circle or reversely to a center of a circle, that is, a virtual center of a circle is set. At the same time, the magnetic thrust has only one direction, which is either directed to the center of the circle, that is, to push the plasma toward the center of the circle, or reversely to the center of the circle, which is equivalent to pointing from the center of the circle to the surroundings, that is, to push the plasma away from the center of the circle and diverge. Through oscillation from the inside to the outside or from the outside to the inside, the plasma is evenly diffused in the entire plasma generating module.

[0045] In some possible embodiments, in addition to forming a transversely guided traveling wave magnetic field, the guided magnetic field generating module is also used to form a rotating magnetic field. The rotating magnetic field is configured to form axial magnetic lines perpendicular to the plasma and cause the plasma to perform Larmor whirls along the axial magnetic lines. The vertical direction is a vertically upward longitudinal direction. Under the action of the rotating magnetic field, the plasma is subjected to the Lorentz force, thereby avoiding irregular motion and collision of the plasma under the constraint of the Lorentz force, reducing losses, and each plasma will perform Larmor whirls along the axial magnetic lines along the Lorentz force it receives in the rotating magnetic field, that is, spiral upward motion, effectively increasing the axial propagation distance of the charged particles.

[0046] Therefore, under the action of the traveling wave magnetic field, the plasma diffuses in the circumferential lateral direction, and under the action of the rotating magnetic field, the plasma diffuses in the vertical longitudinal direction. Therefore, under the joint action of the traveling wave magnetic field and the rotating magnetic field, the plasma exhibits an oblique upward spiral motion, and under the reciprocating magnetic thrust, the central trajectory line may also be a wavy oblique upward spiral motion, which further improves the control and confinement capabilities of the plasma and increases the propagation distance.

[0047] As an implementation method, refer to Figure 1The guide magnetic field generating module includes a magnetic field control unit 21 and at least one magnetic core array 22, each magnetic core array 22 corresponds to a traveling wave sub-magnetic field, the magnetic core array 22 includes N U-shaped magnetic core units 24 with excitation coils 23 arranged at intervals, the two polarity ends 25 of each magnetic core unit 24 are wound around the excitation coil 23, the interval between the two magnetic core units 24 is 5 to 10 mm, wherein N is greater than or equal to 3, and the magnetic field control unit 21 is electrically connected to the excitation coils 23 of each magnetic core unit 24;

[0048] The magnetic field control unit 21 is configured to sequentially supply N-phase excitation currents with a phase sequence of 0°, 360° / N, 360°*2 / N . . . 360°*(N-1) / N to the excitation coils 23 of the magnetic core units 24 in the same magnetic core array 22 .

[0049] For example, N is equal to 4, and the magnetic field control unit 21 is a traveling wave magnetic field power driver, and the excitation currents of different phase sequences are respectively input to the four excitation coils 23, and the four-phase excitation currents of 0°, 90°, 180°, and 270° are sequentially passed, and the excitation current alternately excites the N and S magnetic poles at the left and right polarity ends 25 of the U-shaped magnetic core, and the amplitude, frequency, and phase of the current are adjusted to control the intensity, speed, and direction of travel of the traveling wave magnetic field. Furthermore, in this embodiment, the traveling wave magnetic field is controlled to move back and forth in both directions, that is, to move to the left first and then to the right within a set period, so as to control the charged particles to oscillate back and forth on the surface of the plasma generating module, so as to increase the discharge uniformity of the surface discharge plasma. In addition, most of the magnetic lines of force formed by the N and S magnetic poles at the left and right ends of the U-shaped magnetic core unit 24 with the excitation coil 23 pass through the plasma vertically, which are defined as axial magnetic lines of force, and further constrain the charged particles to spiral around the axial magnetic lines of force.

[0050] Reference Figure 2 Of course, N can also be equal to 3, or other integers greater than 3. In the embodiment where N is equal to 3, the traveling wave magnetic field power driver inputs excitation currents of different phase sequences to the three excitation coils 23 respectively, and passes three-phase excitation currents of 0°, 120°, and 240° in sequence. A traveling wave magnetic field can also be generated in the surface discharge plasma. The amplitude, frequency and phase of the excitation current are controlled by the magnetic field control unit 21 to control the intensity, speed and direction of travel of the traveling wave magnetic field.

[0051] Combination Figure 1 As an embodiment, a dielectric barrier surface discharge method is adopted, and the plasma generating module includes a plasma control unit 11 and a dielectric barrier surface discharge component 12. The dielectric barrier surface discharge component 12 includes a metal layer 13, an insulating medium layer 14 and a ground electrode layer 15 which are closely attached from bottom to top. The metal layer 13 and the ground electrode layer 15 are made of non-magnetic materials. Figure 1In the figure, the metal layer 13 is indicated by a dotted line. The metal layer 13 is placed at the bottom. The area of ​​the insulating medium layer 14 is larger than that of the metal layer 13. The top layer is the ground electrode layer 15. In this embodiment, the metal layer 13 is a copper plate, and the ground electrode layer 15 is composed of a nickel-chromium alloy wire. The ground electrode layer 15 includes a plurality of sub-queue electrodes 16 arranged side by side. At least one sub-queue electrode 16 is arranged above one or more magnetic core arrays 22, that is, a specific number of sub-queue electrodes 16 are regarded as a minimum surface discharge unit, and one or more magnetic core arrays 22 are correspondingly arranged below. The one or more magnetic core arrays 22 serve as a magnetic control sub-unit, and a current with a uniform change mode is passed through to form a uniform traveling wave magnetic field and rotating magnetic field, meaning that The idea is that, within the magnetic control range of the same control method, the plasma generated by a specific number of sub-queue electrodes 16 is uniformly magnetically guided. More specifically, electrode gaps are provided between adjacent sub-queue electrodes 16 to avoid direct contact or close distance between adjacent sub-queue electrodes 16, and the extension direction of the sub-queue electrodes 16 is consistent with the direction of magnetic thrust in the traveling wave sub-magnetic field to which they belong. The plasma ionized on the sub-queue electrodes 16 has a certain diffusion distance in the depth direction, and each sub-queue electrode 16 is equivalent to having its corresponding lateral diffusion area. Under the action of the lateral magnetic thrust, it is more conducive to the lateral diffusion of the plasma in the corresponding lateral diffusion area, thereby ensuring the diffusion effect of each sub-queue electrode 16.

[0052] The plasma control unit 11 provides a high-voltage excitation power supply to the dielectric barrier surface discharge component 12 , and the high-voltage excitation power supply is an AC power supply or a pulse power supply.

[0053] Furthermore, the plasma control unit 11 and the magnetic field control unit 21 serve as driving control units, which can be connected to the main control module 30. Different parameters can be set through the main control module 30 to adapt to the specific conditions of the dielectric barrier surface discharge component 12 and the magnetic core array 22, such as setting the upper limit of the discharge voltage, the phase of the excitation current, etc. The plasma control unit 11 and the magnetic field control unit 21 are responsible for outputting according to the settings of the main control module 30.

[0054] As an implementation mode, the dielectric barrier surface discharge component 12 is arranged above the corresponding magnetic core array 22, and a matching gap is provided between the dielectric barrier surface discharge component 12 and the magnetic core array 22, and a non-magnetic shielding insulating medium is provided in the matching gap. The non-magnetic shielding insulating medium can be air or quartz glass and other materials. The matching gap is 5 to 10 mm. In this embodiment, 5 mm quartz glass is used to fill the middle matching gap, that is, to ensure that the traveling wave magnetic field and the rotating magnetic field formed by the magnetic core array 22 can guide the area where the dielectric barrier surface discharge component 12 is located, and to separate a certain gap to prevent the discharge pressure of the dielectric barrier surface discharge component 12 from affecting or damaging the magnetic core array 22.

[0055] Furthermore, the U-shaped magnetic core unit 24 includes two polarity ends 25, and the width D1 of a single polarity end 25 in the parallel direction of the sub-queue electrodes 16 is greater than or equal to the distance d1 between the farthest structural parts of two adjacent sub-queue electrodes 16 in the parallel direction, and the minimum distance D2 between the two polarity ends 25 is less than the distance d2 between the closest structural parts of two adjacent sub-queue electrodes 16 in the parallel direction, which is equivalent to the size of the single polarity end 25 in the horizontal depth direction of the parallel sub-queue electrodes 16. Since the sub-queue electrodes 16 may be of various shapes, the two adjacent sub-queue electrodes 16 are used as The measurement object is that the two sub-queue electrodes 16 arranged side by side have the farthest structure part and the closest structure part in the depth direction, the distance between the two farthest structure parts on the outside of the two sub-queue electrodes 16 is the maximum spacing, the distance between the two closest structure parts on the inside is the minimum spacing, the width D1 of a single polarity end 25 is greater than or equal to the maximum spacing d1, and the minimum distance D2 between the two polarity ends 25 is less than the minimum spacing d2. The above method is mainly to allow the traveling wave magnetic field and the rotating magnetic field generated by the magnetic core array 22 composed of N magnetic core units 24 to completely cover the dielectric barrier surface discharge component 12. It should be noted that when the number of sub-queue electrodes 16 arranged side by side is large, the distance between the two polarity ends 25 can be increased by setting the width of a single polarity end 25 equal to the maximum spacing of the three sub-queue electrodes 16, or one more group of magnetic core arrays 22 can be set in the side-by-side direction.

[0056] Embodiment 1:

[0057] Reference Figure 1 In the present embodiment 1, the sub-queue electrode 16 is linear, and there are 6 linear ground electrodes in total. The spacing between two adjacent linear ground electrodes is 10 mm. The corresponding magnetic core array 22 includes 4 U-shaped magnetic core units 24. The spacing between two magnetic core units 24 is 10 mm. The height of each magnetic core unit 24 is 52 mm, the width of a single polarity end 25 is 20 mm, the depth of the U-shaped groove is 30 mm, and the minimum distance between the two polarity ends 25 is 8 mm, that is, 48 ​​mm in the side-by-side depth direction. The total depth of the 6 linear ground electrodes is 50 mm, which can ensure that the traveling wave magnetic field and the rotating magnetic field generated by the magnetic core array 22 can completely cover the corresponding ground electrode layer 15.

[0058] Embodiment 2:

[0059] Reference Figure 3In the second embodiment, the sub-queue electrode 16 is in a linear grid shape, that is, a plurality of grids are arranged along a straight line, connected to each other to form a chain. Since the grids have a distance in the depth direction, the two linear grid ground electrodes form a maximum spacing and a minimum spacing. In the present embodiment, the width of the grid itself is 5 mm, and the center spacing of the two linear grid ground electrodes is 15 mm, which is equivalent to a maximum spacing of 20 mm and a minimum spacing of 10 mm. It is also necessary to ensure that the width of a single polarity end 25 is greater than or equal to 20 mm, and the minimum distance between the two polarity ends 25 is less than 10 mm.

[0060] Embodiment 3:

[0061] In this embodiment 3, based on the sub-array electrodes 16 and the magnetic core array 22 in embodiment 1, the magnetic field distribution and the self-induced current distribution in one cycle are simulated and calculated by using COMSOL Multiphysics numerical simulation software. Figure 4 and Figure 5 The distribution of the magnetic field intensity of the traveling wave magnetic field in the plasma and the traveling wave magnetic field waveform in one cycle, where the input excitation current peak is 100A and the frequency is 6000Hz. The corresponding moments in the figure are (a) t = T / 4, (b) t = T / 2, (c) t = 3T / 4, and (d) t = T.

[0062] from Figure 4 It can be seen that the magnetic field strength changes with time, and the N and S levels (i.e., peaks and troughs) move continuously with time. Figure 5 The numerical change of magnetic field intensity is more clearly expressed. For example, at a time interval of T / 4, the peak of the traveling wave magnetic field moves forward by T / 4 in space, and the waveform of the traveling wave magnetic field is approximately a sine wave. The simulation results show that the traveling wave magnetic field generating device of this structural size can generate a stable traveling wave magnetic field.

[0063] The distribution of self-induced current generated by the traveling wave magnetic field at different times in the surface discharge plasma is shown in the figure below: Figure 6 The phase sequence of the excitation current passing through the magnetic core is as follows: Figure 1 As shown in the figure, from left to right, they are 0°, 90°, 180°, and 270°, and the magnetic field moves to the right along a straight line. In the model, the initial electron density of the plasma is n e0 =1×10 12 cm -3 , the characteristic frequency v of the plasma e =1GHz; the speed of the traveling magnetic field is V w=600m / s, frequency is 6000Hz. It can be seen from the figure that the traveling magnetic field can generate self-induced current in the plasma, and the distribution of induced current is different at different times. Among them, (a) t = T, (b) t = T / 4, (c) t = T / 2, (d) t = 3T / 4.

[0064] The traveling magnetic field and the induced current in the surface discharge plasma couple to produce electromagnetic thrust. This process can be expressed by Maxwell's equations

[0065]

[0066]

[0067]

[0068] J=σE

[0069] B=μH

[0070] The force exerted by the traveling magnetic field on the current is expressed as

[0071] f=J×B

[0072] Compared with the prior art, the above embodiment provides a surface discharge plasma magnetron system, which forms a traveling wave magnetic field in the space where the plasma generating module is located, and the entire traveling wave magnetic field can be divided into at least one traveling wave sub-magnetic field, each traveling wave sub-magnetic field can form an induced current in the plasma within the corresponding magnetron range, and the induced current and the traveling wave sub-magnetic field that changes in time and space are coupled to generate a magnetic thrust, so that the plasma moves in the direction of the set magnetic field change, and the plasma just generated by the initial breakdown voltage discharge is diffused in a direction, and the plasma is uniformly distributed by controlling the magnetic field, thereby reducing the discharge voltage;

[0073] By forming a rotating magnetic field in the space where the plasma generating module is located and utilizing the axial magnetic lines of force perpendicular to the plasma in the rotating magnetic field, the charged high-energy active substances in the plasma perform Larmor cyclotron motion around the axial magnetic lines of force under the action of the Lorentz force of the rotating magnetic field, and diffuse spirally upward, thereby effectively increasing the vertical axial propagation distance of the charged particles.

[0074] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0075] The above embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for those of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A surface discharge plasma magnetron system, characterized in that: include: A plasma generating module, used for generating plasma; A guide magnetic field generating module is provided at one side of the plasma generating module, and is used to form a traveling wave magnetic field that changes cyclically according to a set period, wherein the traveling wave magnetic field includes at least one traveling wave sub-magnetic field, and the traveling wave sub-magnetic field is configured to form an induced current in the plasma within its magnetic control range, and to apply a magnetic thrust to the plasma to cause it to move laterally; The set period includes a forward sub-period and a reverse sub-period, the traveling wave magnetic field in the forward sub-period applies a first-direction magnetic thrust to the plasma, and the traveling wave magnetic field in the reverse sub-period applies a second-direction magnetic thrust to the plasma, and in the same traveling wave sub-magnetic field, the first-direction magnetic thrust and the second-direction magnetic thrust applied to the plasma are two opposite-direction forces along the same straight line; The plurality of traveling wave sub-magnetic fields are uniformly distributed around the same center of a circle, and at the same time, the magnetic thrusts exerted by different traveling wave sub-magnetic fields on the plasma in their respective magnetic control ranges are simultaneously directed forwardly to the same center of a circle or reversely to the same center of a circle; The guide magnetic field generating module comprises a magnetic field control unit and at least one magnetic core array, wherein the magnetic core array comprises N U-shaped magnetic core units with excitation coils arranged at intervals, wherein N is greater than or equal to 3, and the magnetic field control unit is electrically connected to the excitation coils of each of the magnetic core units respectively; The magnetic field control unit is configured to sequentially supply N-phase excitation currents with a phase sequence of 0°, 360° / N, 360°*2 / N…360°*(N-1) / N to the excitation coils of the magnetic core units in the same magnetic core array; The U-shaped magnetic core unit includes two polarity ends, and the width of a single polarity end in the side-by-side direction of the sub-queue electrodes is greater than or equal to the distance between the farthest structural parts of two adjacent sub-queue electrodes in the side-by-side direction, and the minimum distance between the two polarity ends is less than the distance between the closest structural parts of two adjacent sub-queue electrodes in the side-by-side direction.

2. A surface discharge plasma magnetron system as claimed in claim 1, characterized in that: A plurality of the traveling wave sub-magnetic fields are arranged side by side, and the magnetic thrusts exerted by different traveling wave sub-magnetic fields on the plasma in their respective magnetic control ranges are parallel to each other.

3. A surface discharge plasma magnetron system according to any one of claims 1 to 2, characterized in that: The guide magnetic field generating module is also used to form a rotating magnetic field, and the rotating magnetic field is configured to form axial magnetic lines perpendicular to the plasma and make the plasma perform Larmor cyclotron along the axial magnetic lines.

4. A surface discharge plasma magnetron system as claimed in claim 3, characterized in that: The plasma generating module comprises a plasma control unit and a dielectric barrier surface discharge component, wherein the dielectric barrier surface discharge component comprises a metal layer, an insulating medium layer and a ground electrode layer which are tightly fitted from bottom to top, wherein the metal layer and the ground electrode layer are made of non-magnetic materials, and the ground electrode layer comprises a plurality of sub-queue electrodes arranged side by side, wherein electrode gaps are provided between adjacent sub-queue electrodes, and the extension direction of the sub-queue electrodes is consistent with the direction of magnetic thrust in the traveling wave sub-magnetic field to which they belong.

5. A surface discharge plasma magnetron system as claimed in claim 4, characterized in that: A matching interval is arranged between the dielectric barrier surface discharge assembly and the magnetic core array, a non-magnetic shielding insulating medium is arranged in the matching interval, and the matching interval is 5-10 mm.

6. A surface discharge plasma magnetron system as claimed in claim 4, characterized in that: The sub-queue electrodes are in a linear shape or a linear grid shape.

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