Switching network unit for nuclear fusion magnet power supply plasma breakdown

Abstract

The utility model provides a switch network unit for plasma breakdown of a nuclear fusion magnet power supply, which is connected in series between a power supply and a magnet load, and comprises an input connection bar which is arranged on a bottom plate and is connected with the power supply; the output connecting bar is installed on the bottom plate and connected with a magnet load, the input connecting bar and the output connecting bar are arranged on the two sides of the insulating layer, the projections of the input connecting bar and the output connecting bar on the insulating layer are overlapped, and currents in the input connecting bar and the output connecting bar on the two sides of the insulating layer are equal in magnitude and opposite in direction; the commutation switch network comprises a plurality of commutation switches which are connected in parallel between the input connection bar and the output connection bar; and the current-limiting resistor is connected in series between the input connection bar and the output connection bar and is connected in parallel with the commutation switch. The currents flowing through the symmetrical parts on the two sides of the insulating layer are equal in magnitude and opposite in direction, so that magnetic fields generated by the currents are offset, stray inductance can be effectively reduced, and the current sharing effect of each converter switch is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of electronic power, in particular to a switch network unit for plasma breakdown of a nuclear fusion magnet power supply. Background Art

[0002] In a magnetic confinement nuclear fusion device, the magnet power supply usually uses a switch network to actively disconnect and generate high voltage, thereby generating plasma current through high voltage breakdown at the initial stage of discharge.

[0003] The core equipment of the switch network is the commutation switch of the fully controlled solid-state switch device with fast breaking speed, high reliability, good stability, long life and good maintainability. In the switch network unit of this structure, multiple high-power solid-state switch devices work in series and parallel. The branch voltage and current equalization characteristics are particularly important and are an important factor affecting the switching capacity and reliability of the switch network unit. However, in the application environment of nuclear fusion plasma breakdown power supply, the general electrical switch network design is difficult to meet this special operating condition.

[0004] Therefore, there is an urgent need for a switch network unit for nuclear fusion magnet power supply plasma breakdown to meet the switching capacity and reliability required by the switch network unit for nuclear fusion plasma breakdown power supply. Utility Model Content

[0005] The present application provides a switch network unit for nuclear fusion magnet power supply plasma breakdown, which at least solves the technical problem of how to apply nuclear fusion magnet power supply plasma breakdown in the related art.

[0006] An embodiment of the present application provides a switch network unit for plasma breakdown of a nuclear fusion magnet power supply, wherein the switch network unit is connected in series between the power supply and the magnet load, and comprises: an input connection bar, mounted on a base plate, connected to the magnet load, wherein the input connection bar and the output connection bar are arranged on both sides of an insulating layer, and the projections of the input connection bar and the output connection bar on the insulating layer overlap, wherein the currents in the input connection bar and the output connection bar on both sides of the insulating layer are equal in magnitude and opposite in direction; a commutation switch network, comprising a plurality of commutation switches connected in parallel between the input connection bar and the output connection bar; a current limiting resistor, connected in series between the input connection bar and the output connection bar, and connected in parallel with the commutation switch.

[0007] In one embodiment, a midpoint terminal of the input connection row is connected to the power source.

[0008] In one embodiment, a midpoint terminal of the output connection row is connected to the magnetic load.

[0009] In one embodiment, a plurality of first branch connection rows have one end connected one-to-one with the input end of the converter switch, and the other end connected to the input connection row at equal intervals; a plurality of second branch connection rows have one end connected one-to-one with the output end of the converter switch, and the other end connected to the output connection row at equal intervals.

[0010] In one embodiment, the first branch connection bars are symmetrically distributed on both sides of the midpoint terminal of the input connection bar; and the second branch connection bars are symmetrically distributed on both sides of the midpoint terminal of the output connection bar.

[0011] In one embodiment, the current direction of the commutation switch is perpendicular to the current discharge of the input connection bar and the output connection bar.

[0012] In one embodiment, the switch network unit further comprises: at least one bracket, one end of which is fixedly mounted on the bottom plate, and the other end of which is fixedly connected to the input connection bar, the insulating layer and the output connection bar.

[0013] In one embodiment, the current limiting resistor is a resistor with adjustable resistance.

[0014] In one embodiment, the switch network unit further comprises: a base, fixedly mounted on the bottom plate, for fixing and dissipating heat for the commutation switch.

[0015] In one embodiment, the switch network unit further includes: a driving board, mounted on the base plate, having a plurality of driving circuits corresponding one to one with the commutation switches, the driving circuits being connected to the control ends of the commutation switches for controlling the on and off of the commutation switches.

[0016] In one embodiment, the switch network unit also includes: a current sensor, which is arranged on the branch where the commutation switch is located and the main circuit where the input connection bar and the output connection bar are located, and is used to collect branch current and main current; a voltage sensor, which is arranged at both ends of the current limiting resistor, and is used to collect the voltage at both ends of the current limiting resistor, and is used to trigger an alarm when the voltage is abnormal.

[0017] This application has at least the following beneficial effects:

[0018] All devices in the switch network unit provided by the present application are installed on the bottom plate, the input connection row is connected to the power supply, the output connection row is connected to the magnetic load, and the input connection row and the output connection row are symmetrically and closely arranged on both sides of the insulating layer. The projections of the input connection row and the output connection row on the insulating layer overlap, and the size parameters of the input connection row and the output connection row on both sides of the insulating layer are the same, so as to ensure that when the commutation switch is turned on, the currents flowing through the symmetrical parts on both sides of the insulating layer are equal in magnitude and opposite in direction, so as to offset the magnetic field generated by the current, which can effectively reduce the stray inductance, thereby reducing the influence of the stray inductance on the commutation switch, and improving the current sharing effect of each commutation switch.

[0019] Furthermore, the converter switch can be connected to the input connection bar and the output connection bar through the branch connection bar. The branch connection bar may include a first branch connection bar on the input side and a second branch connection bar on the output side, wherein one end of the first branch connection bar is fixedly connected to the input connection bar, and the other end is connected to the input end of the converter switch; one end of the second branch connection bar is fixedly connected to the output connection bar, and the other end is connected to the output end of the converter switch. All first branch connection bars and second branch connection bars use connection bars with the same size parameters, and are evenly distributed on both sides of the midpoint terminal, which reduces the impedance difference between the converter switch branches and improves the current sharing effect.

[0020] Furthermore, the current flowing through the commutation switch is perpendicular to the current flowing through the input connection bar and the output connection bar, so as to reduce the influence of the current magnetic field of the input connection bar and the output connection bar on the commutation switch and improve the current sharing effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The accompanying drawings herein are incorporated in and constitute a part of the specification, illustrate embodiments consistent with the present utility model, and together with the description, are used to explain the principles of the present utility model.

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the utility model or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0023] Figure 1 A schematic diagram of a circuit structure of an exemplary switch network unit according to an embodiment of the present application;

[0024] Figure 2 is a schematic diagram of the structure of another exemplary switch network unit in an embodiment of the present application;

[0025] Figure 3 is an enlarged schematic diagram of a local area A in an exemplary switch network unit in an embodiment of the present application;

[0026] Figure 4 Schematic diagram of a driving part of an exemplary switch network unit in an embodiment of the present application. DETAILED DESCRIPTION

[0027] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present application.

[0028] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, including a series of units, systems, products or devices is not necessarily limited to those units, systems, products or devices clearly listed, but may include units, systems, products or devices that are not clearly listed.

[0029] The present application provides a switch network unit for nuclear fusion magnet power supply plasma breakdown, see Figure 1-3 As shown, the switch network unit 100 is connected in series between the power supply and the magnetic load, and specifically includes: an input connection bar 10, installed on the base plate 50, and connected to the power supply; an output connection bar 20, installed on the base plate 50, and connected to the magnetic load, the input connection bar 10 and the output connection bar 20 are arranged on both sides of the insulating layer 11, and the projections of the input connection bar 10 and the output connection bar 20 on the insulating layer 11 overlap, wherein the currents in the input connection bar 10 and the output connection bar 20 on both sides of the insulating layer 11 are equal in magnitude and opposite in direction; a commutation switch network 30, including a plurality of commutation switches 31 connected in parallel between the input connection bar 10 and the output connection bar 20; a current limiting resistor 40, connected in series between the input connection bar 10 and the output connection bar 20, and connected in parallel with the commutation switch 31.

[0030] In this embodiment, the working principle of the switch network unit 100 is as follows: the commutation switch 31 receives an opening instruction, the discharge current of the power supply flows in through the input connection bar 10, passes through the input end of the commutation switch 31, the output end of the commutation switch 31 and the output connection bar 20 in sequence, and flows to the magnetic load, and the magnetic load starts to run after being excited by the power supply; thereafter, the commutation switch 31 receives a shutdown instruction, the branch where the commutation switch 31 is located is cut off, and the current flows in through the input connection bar 10, and flows out through the current limiting resistor 40 and the output connection bar 20 in sequence.

[0031] In this embodiment, all devices in the switch network unit 100 are mounted on the bottom plate 50, the input connection bar 10 is connected to the power supply, the output connection bar 20 is connected to the magnetic load, and the part of the input connection bar 10 and the output connection bar 20 used for connecting the commutation switch 31 is closely arranged on both sides of the insulating layer 11. The input connection bar 10 and the output connection bar 20 of this part have the same size parameters to ensure that when the commutation switch 31 is turned on, the currents flowing through the symmetrical parts on both sides of the insulating layer 11 are equal in magnitude and opposite in direction to offset the magnetic field generated by the current, which can effectively reduce the stray inductance, thereby reducing the influence of the stray inductance on the commutation switch 31 and improving the current sharing effect of each commutation switch 31.

[0032] In one embodiment, the input connection bar 10 and the output connection bar 20 may be DC busbars such as copper busbars and aluminum busbars, or DC busbars such as cables. The commutation switch 31 may be a fully controlled solid-state switch device, for example, a fully controlled solid-state switch device such as MOSFET, IGBT, GTO, GTR, etc. In this embodiment, the input connection bar 10 and the output connection bar 20 are taken as copper busbars, and the commutation switch 31 is described in detail by taking IGBT as an example.

[0033] In this embodiment, a fully controlled solid-state switch device is used, so that the switch network unit 100 has a fast breaking speed, low heat loss, simple structure, easy maintenance and operation, and is convenient for connecting to different magnetic coil circuits.

[0034] In one embodiment, the power supply is connected to the midpoint terminal of the input connection row 10, and / or the magnetic load is connected to the midpoint terminal of the output connection row 20, that is, the midpoint terminal of the input connection row 10 is used as the input position and / or the midpoint terminal of the output connection row 20 is used as the output position, thereby reducing the length between the current input end and / or the output end and the converter switch 31, reducing the impedance difference between the branches where each converter switch 31 is located, and improving the current sharing effect of the converter switch 31.

[0035] In one embodiment, the commutation switches 31 are evenly distributed and connected on both sides of the midpoint terminal. In this embodiment, the commutation switches 31 can be connected to the input connection bar 10 and the output connection bar 20 through the branch connection bar. Figure 3As shown, the branch connection bar may include a first branch connection bar 60 on the input side and a second branch connection bar 70 on the output side, wherein one end of the first branch connection bar 60 is fixedly connected to the input connection bar 10, and the other end is connected to the input end of the converter switch 31; one end of the second branch connection bar 70 is fixedly connected to the output connection bar 20, and the other end is connected to the output end of the converter switch 31. All first branch connection bars 60 and second branch connection bars 70 use connection bars with the same size parameters and are evenly distributed on both sides of the midpoint terminal, which reduces the impedance difference between the branches of the converter switch 31 and improves the current sharing effect.

[0036] In order to further reduce the impedance difference, in another embodiment, the resistance of the first branch connection bar 60 and the second branch connection bar 70 decreases successively from the midpoint terminal to both sides. In this embodiment, the resistance can be reduced successively by increasing the width or thickness of the branch connection bar once. By measuring the resistance increase of each branch connection bar in the installation position of the input connection bar 10 and the output connection bar 20, the resistance reduction of each branch connection bar is determined, so that the resistance between the power supply through the input connection bar 10 and the input end of each converter switch 31 is the same, and the resistance between the power supply through the output connection bar 20 and the output end of each converter switch 31 is the same, thereby further improving the current sharing effect.

[0037] In other embodiments, the connection position between the power supply and the input connection bar 10, and the connection position between the magnetic load and the output connection bar 20 can also be set at other positions other than the mid-point terminal, by matching the resistance of the parallel branches to achieve close resistance between each converter switch 31 and the power supply, and close resistance between each converter switch 31 and the magnetic load, thereby reducing the impedance difference between the branches of the converter switch 31 and improving the current sharing effect.

[0038] In one embodiment, in order to further reduce the influence of the magnetic field generated by the current in the input connection bar 10 and the output connection bar 20 on the commutation switch 31, in some embodiments, the current flowing through the commutation switch 31 is perpendicular to the current flowing through the input connection bar 10 and the output connection bar 20, so as to reduce the influence of the current magnetic field of the input connection bar 10 and the output connection bar 20 on the commutation switch 31 and improve the current sharing effect. Exemplarily, the first branch connection bar 60 can be perpendicular to the input connection bar 10, and the second branch connection bar 70 can be perpendicular to the output connection bar 20. The installation angle of the commutation switch 31 can also be set so that the current direction inside the commutation switch 31 is perpendicular to the input connection bar 10 and the output connection bar 20.

[0039] In one embodiment, the switch network unit 100 further includes: a base, fixedly mounted on the bottom plate 50, for fixing and dissipating heat for the commutation switch 31. In this embodiment, each base can be mounted with one, two or more commutation switches 31.

[0040] In one embodiment, a bracket 51 is provided between the input connection bar 10 and the output connection bar 20 and between the insulating layer 11 between the input connection bar 10 and the output connection bar 20 and the bottom plate 20, for fixing the input connection bar 10 and the output connection bar 20 and the insulating layer 11 between the input connection bar 10 and the output connection bar 20 on the bottom plate 50. In this embodiment, the bracket 51 can be fastened by bolts, studs, rivets and other fastening methods. In this embodiment, the stud fastening method is taken as an example for description. In order to achieve insulation between the input connection bar 10 and the output connection bar 20, an insulating sleeve is provided between the stud and the input connection bar 10 and / or between the stud and the output connection bar 20.

[0041] In one embodiment, the current limiting resistor 40 is an adjustable resistance resistor. In this embodiment, the current limiting resistor 40 is a modular non-inductive resistor with adjustable resistance. Figure 2 As shown, one end of the current limiting resistor 40 is connected to the input connection row 10 through the first resistor connection row 80, and the other end is connected to the output connection row 20 through the second resistor connection row 90. By adjusting the resistance value of the current limiting resistor 40, a wide range of circuit current change rate modulation under different resistance values ​​can be achieved.

[0042] In one embodiment, if Figure 4 As shown, it also includes a driving part 200. In this embodiment, the driving part includes a driving board 201, which is installed on the bottom plate 50 and has a plurality of driving circuits corresponding to the commutation switch 31. The driving circuit is connected to the control end of the commutation switch 31 to control the opening and closing of the commutation switch 31. Among them, the plurality of driving circuits can be separately and correspondingly arranged on a plurality of driving boards 201, or can be integrated on one driving board 201. In one embodiment, the driving part can also include a driving board power supply 202: providing power to each driving board 201; a driving signal distribution board 203, receiving a control signal, and sending the control signal to each driving board 201 or each driving circuit through an optical fiber, so that the driving circuit drives the corresponding commutation switch 31.

[0043] In one embodiment, the switch network unit 100 may also include an electrical signal measuring part, wherein the electrical signal measuring part may include a current sensor, which is arranged on the branch where the converter switch 31 is located and the main circuit where the input connecting bus 10 and the output connecting bus 20 are located, and is used to collect branch current and main current.

[0044] In the above embodiments of the present application, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, please refer to the relevant description of other embodiments.

[0045] The above is only a preferred implementation of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. A switch network unit for plasma breakdown of a nuclear fusion magnet power supply, characterized in that: The switch network unit is connected in series between the power source and the magnetic load, and the switch network unit includes: An input connection bar, mounted on the bottom plate and connected to the power supply; An output connection bar is mounted on the bottom plate and connected to the magnetic load, wherein the input connection bar and the output connection bar are arranged on both sides of the insulating layer, and the projections of the input connection bar and the output connection bar on the insulating layer overlap, wherein the currents in the input connection bar and the output connection bar on both sides of the insulating layer are equal in magnitude and opposite in direction; A commutation switch network, comprising a plurality of commutation switches connected in parallel between the input connection bar and the output connection bar; A current limiting resistor is connected in series between the input connection bar and the output connection bar, and is connected in parallel with the current conversion switch.

2. The switch network unit for plasma breakdown of a nuclear fusion magnet power supply according to claim 1, characterized in that: The midpoint terminal of the input connection row is connected to the power supply.

3. The switch network unit for plasma breakdown of a nuclear fusion magnet power supply according to claim 1 or 2, characterized in that: The midpoint terminal of the output connection row is connected to the magnetic load.

4. The switch network unit for plasma breakdown of a nuclear fusion magnet power supply according to claim 1, characterized in that: Also includes: A plurality of first branch connection bars, one end of which is connected to the input end of the commutation switch in a one-to-one correspondence, and the other end of which is connected to the input connection bar at equal intervals; A plurality of second branch connection bars have one end connected to the output end of the commutation switch in a one-to-one correspondence, and the other end connected to the output connection bar at equal intervals.

5. The switch network unit for plasma breakdown of a nuclear fusion magnet power supply according to claim 1, characterized in that: The current direction in the commutation switch is perpendicular to the current discharge of the input connection bar and the output connection bar.

6. The switch network unit for plasma breakdown of a nuclear fusion magnet power supply according to claim 1, characterized in that: Also includes: At least one bracket has one end fixedly mounted on the bottom plate and the other end fixedly connected to the input connection bar, the insulating layer and the output connection bar.

7. The switch network unit for plasma breakdown of a nuclear fusion magnet power supply according to claim 1, characterized in that: The current limiting resistor is a resistor with adjustable resistance.

8. The switch network unit for plasma breakdown of a nuclear fusion magnet power supply according to claim 1, characterized in that: Also includes: The base is fixedly mounted on the bottom plate and is used for fixing and dissipating heat for the commutation switch.

9. The switch network unit for plasma breakdown of a nuclear fusion magnet power supply according to claim 1, characterized in that: Also includes: The driving board is mounted on the bottom plate and has a plurality of driving circuits corresponding to the commutation switches one by one. The driving circuits are connected to the control ends of the commutation switches and are used to control the on and off of the commutation switches.

10. The switch network unit for plasma breakdown of a nuclear fusion magnet power supply according to claim 1, characterized in that: Also includes: A current sensor is provided on the branch where the commutation switch is located and the main circuit where the input connection bar and the output connection bar are located, and is used to collect branch current and main circuit current; The voltage sensor is arranged at both ends of the current limiting resistor, and is used to collect the voltage at both ends of the current limiting resistor, and is used to trigger an alarm when the voltage is abnormal.

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