Double bunch separation system

Abstract

The present invention relates to an impact magnet system and a dual-bunch separation system, the impact magnet system includes a vacuum chamber and an impact magnet fixed in the vacuum chamber, the impact magnet includes a magnetic core, a coil and an outer frame, the magnetic core is fixed in the outer frame, the magnetic core has a window, the coil is arranged in the window; a first joint is connected to the first end of the coil, and a second joint is provided on the second end of the coil, and the first joint and the second joint extend outside the outer frame; a vacuum through-wall component electrode interface is provided on the vacuum chamber, and the first joint and the second joint are electrically connected to the vacuum through-wall component electrode interface respectively; a beam outlet and a beam inlet are also provided on the vacuum chamber, and the beam inlet, the window and the beam outlet are connected in sequence.

Description

Technical Field

[0001] The present invention relates to the technical field of beam distribution, and more particularly to an impact magnet system and a dual-bunch separation system. Background Art

[0002] As a representative of contemporary advanced light sources, free-electron lasers (FELs) demonstrate tremendous potential and value in diverse fields, including scientific research, materials science, biomedicine, and industrial applications. To improve the efficiency of FELs and expand their applications, researchers are constantly exploring and innovating, with the dual-bunch operation of linear accelerators being a key technological approach.

[0003] In dual-bunch operation, the linear accelerator can simultaneously generate two independent electron bunches. Through a specific beam distribution mechanism, these two bunches are delivered to different undulator lines, achieving multifunctional and highly efficient laser output. In this process, the impact magnet is a key component, responsible for effectively separating the two bunches.

[0004] Internationally, there have been some successful attempts at separating two beams in FEL devices. For example, a Swiss free electron laser facility, employing a zircon-type impactor magnet and a solid-state excitation power source, has successfully achieved two-beam separation with a time interval of 28 nanoseconds. However, this approach may have limitations for separating two beams with shorter or longer time intervals, and technical details and cost considerations may also limit its widespread application.

[0005] Against this backdrop, the Shanghai Soft X-ray Free Electron Laser Facility's linear accelerator has put forward more advanced and adaptable requirements. The device operates in a dual-bunch mode with a time interval of 100ns between the two bunches, which poses a higher challenge to the performance of the impact magnet. Summary of the Invention

[0006] The object of the present invention is to provide an impact magnet system and a dual-bunch separation system to solve the technical problem that the existing impact magnet cannot achieve dual-bunch separation with a time interval of 100 ns.

[0007] Based on the above-mentioned purpose, the present invention provides an impact magnet system on the one hand, including a vacuum chamber and an impact magnet fixed in the vacuum chamber, the impact magnet including a magnetic core, a coil and an outer frame, the magnetic core is fixed in the outer frame, the magnetic core has a window, and the coil is arranged in the window; a first connector is connected to the first end of the coil, and a second connector is provided on the second end of the coil, and the first connector and the second connector extend outside the outer frame; a vacuum wall-penetrating component electrode interface is provided on the vacuum chamber, and the first connector and the second connector are electrically connected to the vacuum wall-penetrating component electrode interface respectively; a beam outlet and a beam inlet are also provided on the vacuum chamber, and the beam inlet, the window and the beam outlet are connected in sequence.

[0008] Furthermore, the vacuum chamber is provided with an observation window and a vacuum gauge.

[0009] Furthermore, the impact magnet system further includes a supporting mechanism, and the vacuum chamber is provided on the supporting mechanism; the supporting mechanism is used to support the vacuum chamber and adjust the position of the vacuum chamber.

[0010] Furthermore, an ion pump is provided on the supporting mechanism, and the ion pump is communicated with the interior of the vacuum chamber to evacuate the vacuum chamber.

[0011] Further, the coil includes a first wire, a second wire, a third wire, a first connecting plate and a second connecting plate, the first wire, the second wire and the third wire all extend along the beam transmission direction, the first wire is located on the first side, the second wire and the second wire are located on the second side opposite to the first side, one end of the second wire forms the first end of the coil, one end of the third wire forms the second end of the coil, the first end and the second end are arranged opposite to each other, the other end of the second wire is connected to the first connecting plate, the other end of the third wire is connected to the second connecting plate, and the two ends of the first wire are respectively connected to the first connecting plate and the second connecting plate.

[0012] Furthermore, an insulating plate is provided between the first joint and the second joint.

[0013] Furthermore, the magnetic core includes a first magnetic core, a second magnetic core and a third magnetic core, all of which extend along the beam transmission direction. The first magnetic core and the second magnetic core are spaced apart along the beam transmission direction. The third magnetic core is located between the first magnetic core and the second magnetic core. The first magnetic core, the third magnetic core and the second magnetic core have windows that are connected in sequence, and the first joint and the second joint extend from the gap between the first magnetic core and the second magnetic core to outside the window.

[0014] Furthermore, the outer frame includes a first frame, a second frame and a third frame, the first frame, the second frame and the third frame all extend along the beam transmission direction, the first frame is located on the first side, the second frame and the third frame are located on the second side, the first frame is fixedly connected to the second frame and the third frame respectively, and the magnetic core is clamped between the first frame and the second frame and the third frame; there is a gap between the second frame and the third frame for the first joint and the second joint to extend out.

[0015] Furthermore, heat dissipation holes are provided on the first wire, the second wire, the third wire, the first connecting plate, the second connecting plate, the first frame, the second frame and the third frame.

[0016] Furthermore, at least one cooling belt is provided on the outer frame, and the cooling belt is connected to the inner wall of the vacuum chamber.

[0017] On the other hand, the present invention provides a dual-bunch separation system, including a controller, a charging power supply, an auxiliary power supply, a trigger, a pulse power source, a timer and the impact magnet system as described above, wherein the controller is electrically connected to the charging power supply, the auxiliary power supply and the pulse power source respectively, the charging power supply is electrically connected to the pulse power source, the auxiliary power supply is electrically connected to the pulse power source, and the pulse power source is electrically connected to the impact magnet system.

[0018] Furthermore, the pulse power source includes a first resistor, a first diode, a second diode, a thyristor, a pulse forming line, a third diode, a second resistor and a capacitor, one end of the charging power supply is grounded, the other end of the charging power supply is connected to one end of the first resistor, the other end of the first resistor is connected to the positive electrode of the first diode, the cathode of the first diode is respectively connected to the negative electrode of the second diode, the cathode end of the thyristor, the first end of the pulse forming line, and one end of the capacitor; the anode of the second diode is connected to the anode end of the thyristor, and the other end of the capacitor is respectively connected to the impact magnetic The first terminal of the impact magnet of the iron system is connected to the second end of the pulse forming line, the second terminal of the impact magnet is grounded, the third end of the pulse forming line is grounded, the fourth end of the pulse forming line is connected to the cathode of the third diode, the anode of the third diode is connected to one end of the second resistor, and the other end of the second resistor is grounded; the positive pole of the trigger is connected to the positive terminal of the trigger input of the thyristor, the negative pole of the trigger is connected to the negative terminal of the trigger input of the thyristor, the positive pole of the auxiliary power supply is connected to the positive terminal of the auxiliary power supply of the thyristor, and the negative pole of the auxiliary power supply is connected to the negative terminal of the auxiliary power supply of the thyristor.

[0019] The single-inductance impact magnet of the present invention can minimize the restriction of the magnet inductance on the leading and trailing edges of the pulse. Based on the energy storage of the pulse forming line PFL, the pulse power supply of the thyristor S1 that quickly turns on the discharge to generate a pulse current can achieve double-bunch separation with a minimum time interval of 100ns. The pulse current has a flat-top width, so it has good compatibility with double-bunch separation with a time interval of 100ns-300ns. And by adding a capacitor C in the pulse discharge circuit, the leading edge of the excitation pulse can be further improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 A schematic structural diagram of an impact magnet system according to an embodiment of the present invention;

[0021] Figure 2 This is a schematic structural diagram of an impact magnet system according to an embodiment of the present invention after removing the top plate of the vacuum chamber;

[0022] Figure 3 A schematic structural diagram of an impact magnet of an impact magnet system according to an embodiment of the present invention;

[0023] Figure 4 This is a schematic structural diagram of an impact magnet system according to an embodiment of the present invention with its outer frame removed;

[0024] Figure 5 A schematic structural diagram of a coil of an impact magnet of an impact magnet system according to an embodiment of the present invention;

[0025] Figure 6 A schematic structural diagram of a magnetic core of an impact magnet of an impact magnet system according to an embodiment of the present invention;

[0026] Figure 7 for Figure 4 Cross-sectional view of

[0027] Figure 8 is a structural block diagram of a dual-bunch separation system according to an embodiment of the present invention;

[0028] Figure 9 is a circuit diagram of a dual-bunch separation system according to an embodiment of the present invention;

[0029] Figure 10 4 is a pulse current simulation waveform diagram according to an embodiment of the present invention. DETAILED DESCRIPTION

[0030] The preferred embodiments of the present invention are given below in conjunction with the accompanying drawings and described in detail.

[0031] like Figure 1 and Figure 2As shown, an embodiment of the present invention provides an impact magnet system 1000, including a vacuum chamber 100 and an impact magnet 200 fixed in the vacuum chamber 100, as shown in FIG. Figure 3 、 Figure 4 As shown, the impact magnet 200 includes a magnetic core 210 with a window 211, a coil 220 and an outer frame 230, the magnetic core 210 is located in the outer frame 230 and is fixedly connected to the outer frame 230, the outer frame 230 is fixedly connected to the vacuum chamber 100, the coil 220 is arranged in the window 211 of the magnetic core 210, the first end of the coil 220 is connected to the first connector 221, the second end of the coil 220 is connected to the second connector 222, the first connector 221 and the second connector 222 extend outside the outer frame 230; the vacuum chamber 100 is provided with a vacuum through-wall component electrode interface 110, the first connector 221 and the second connector 222 are respectively electrically connected to the vacuum through-wall component electrode interface 110, so that the first end of the coil 220 is connected to the vacuum through-wall component electrode interface 110. end and the second end; the vacuum chamber 100 is also provided with a beam inlet 120 and a beam outlet 130, the beam can enter the vacuum chamber 100 from the beam inlet 120, then pass through the magnetic core 210 through the window 211, and leave the vacuum chamber 100 from the beam outlet 130; the vacuum wall-penetrating component motor interface 110 is used to be electrically connected to the excitation pulse power source, so as to input pulse power to the coil 220 through the excitation pulse power source, and make the impact magnet 200 generate a pulse magnetic field, thereby changing the trajectory of the beam and making it deviate from the original path, so that when the pulse current is not connected, the beam will be transmitted along the first trajectory (for example, along the central axis of the magnetic core 210), and when the pulse current is connected, the beam will be offset and transmitted along the second trajectory, thereby realizing the separation of the two bunches.

[0032] In some embodiments, the vacuum chamber 100 may further be provided with an observation window 140 and a vacuum gauge 150 . The observation window 140 is used to observe the interior of the vacuum chamber 100 , and the vacuum gauge 150 is used to measure the vacuum degree in the vacuum chamber 100 .

[0033] In some embodiments, the impact magnet system 1000 may further include a support mechanism 300, on which the vacuum chamber 100 is disposed, and the support mechanism 300 is used to support the vacuum chamber 100. The support mechanism 300 may also be used to adjust the position of the vacuum chamber 100 so that the beam can pass through the center of the impact magnet 200.

[0034] The support mechanism 300 may also be provided with an ion pump 400, which is connected to the interior of the vacuum chamber 100 and is used to remove gas molecules in the vacuum chamber 100, thereby maintaining the vacuum level in the vacuum chamber 100 below a preset value (for example, 1E-5 Pascal).

[0035] like Figure 5As shown, in some embodiments, the coil 220 includes a first wire 223, a second wire 224, a third wire 225, a first connecting plate 226, and a second connecting plate 227. The first wire 223, the second wire 224, and the third wire 225 all extend along the beam transmission direction. The first wire 223 is located on a first side, and the second wire 224 and the third wire 225 are located on a second side opposite the first side. One end of the second wire 224 forms the first end of the coil 220, and one end of the third wire 225 forms the second end of the coil 220. The first and second ends are arranged opposite each other. The other end of the second wire 224 is connected to the first connecting plate 226, and the other end of the third wire 225 is connected to the second connecting plate 227. The two ends of the first wire 223 are respectively connected to the first connecting plate 226 and the second connecting plate 227, thereby forming the coil 220 into a ring shape. An insulating plate 228 may be provided between the first joint 221 and the second joint 222 to insulate the first joint 221 and the second joint 222.

[0036] like Figure 6 As shown, in some embodiments, the magnetic core 210 includes a first magnetic core 212, a second magnetic core 213 and a third magnetic core 214. The first magnetic core 212 and the second magnetic core 213 are spaced apart along the beam transmission direction, and there is a gap between them. The third magnetic core 214 is located between the first magnetic core 212 and the second magnetic core 213 and fills part of the above-mentioned gap. The first magnetic core 212, the third magnetic core 214 and the second magnetic core 213 all have windows, and the windows of the three are connected in sequence. The first joint 221 and the second joint 222 can extend from the rest of the gap to the outside of the window 211.

[0037] In some embodiments, the first magnetic core 212 and the second magnetic core 213 may be formed by splicing a plurality of magnets, for example, by splicing two C-shaped magnets.

[0038] like Figure 7As shown, the first conductor 223 and the second conductor 224 (and the third conductor 225) are arranged opposite each other in the window 211, and the gap between them serves as the beam transmission channel. The first conductor 223, the second conductor 224, the third conductor 225, the first connecting plate 226, and the second connecting plate 227 may all be provided with heat dissipation holes to dissipate heat and prevent overheating of the coil 220. For example, the spacing between the first conductor 223 and the second conductor 224, and the spacing between the first conductor 223 and the third conductor 225, are both Hap = 10 mm. The width of the window 211 is Vap = 12 mm. The first conductor 223, the second conductor 224, and the third conductor 225 are all rectangular copper conductors with a width of Vap = 12 mm and a height of H1 = 5 mm. The length of the first conductor 223 along the beam transmission direction (i.e., perpendicular to the paper) is 500 mm. The magnetic core 210 has a width of V1 = 32 mm, a height of H2 = 40 mm, and a length of 500 mm.

[0039] Continue to refer to Figure 3 The outer frame 230 may include a first frame 231, a second frame 232, and a third frame 233. The first frame 231, the second frame 232, and the third frame 233 all extend along the beam transmission direction. The first frame 231 is located on a first side, and the second frame 232 and the third frame 233 are located on a second side opposite the first side. The second frame 232 and the third frame 233 are spaced apart on the second side. The first frame 231 is fixedly connected to the second frame 232 and the third frame 233, respectively. The magnetic core 210 is sandwiched between the first frame 231, the second frame 232, and the third frame 233. A gap is provided between the second frame 232 and the third frame 233. The gap is used for the first joint 221 and the second joint 222 to pass through, so that the first joint 221 and the second joint 222 extend outside the outer frame 230. The first frame 231, the second frame 232, and the third frame 233 may be provided with heat dissipation holes for heat dissipation.

[0040] The outer frame 230 may further be provided with at least one (eg, two) cooling belts 240 , which are connected to the inner wall of the vacuum chamber 100 and used to transfer heat from the outer frame 230 to the vacuum chamber 100 and dissipate heat outward from the vacuum chamber 100 .

[0041] Coil 220 is a single-turn coil made of oxygen-free copper (oxygen content <0.05%) with a cross-sectional area of ​​12*5mm2. Coil 220 is equivalent to an inductive load, and its inductance is calculated as follows:

[0042]

[0043] Where L is the inductance, μ0 is the vacuum permeability, N is the number of coil turns, H ap(eff) Determined by formula (2), D is the effective length of the magnet.

[0044]

[0045] Based on formulas (1) and (2), the inductance of the coil 220 can be calculated to be L=0.8 μH.

[0046] The excitation current (i.e. pulse current) can be calculated by formula (3):

[0047]

[0048] Where B is the magnetic induction intensity, I is the excitation current, and B can be calculated using formula (4):

[0049]

[0050] Where θ is the deflection angle, E is the beam energy, L is the effective length of the magnet, and v is the beam velocity. Using equations (3) and (4), we can calculate that the magnetic induction intensity B is 200 gauss and the required excitation current is 191 A.

[0051] In an exemplary embodiment, the material of the magnetic core 210 is TN12B nickel-zinc ferrite material.

[0052] The power consumption of the impact magnet consists of two main components: the skin effect of coil 220 at high frequency and the power consumption of the magnetic core. The pulse current frequency is 50 Hz, and the duty cycle is less than 1E-5, so the resistive power consumption of coil 220 is very small. The power consumption of the magnetic core is mainly due to hysteresis loss. The hysteresis loss in the core per unit volume of the magnetic core after one cycle is proportional to the area of ​​the hysteresis loop, and this energy is converted into heat. The hysteresis loss W per unit volume per cycle can be expressed as:

[0053]

[0054] Where K1 is a constant that depends on the material; η is the Steinmetz coefficient. The η of the magnetic core material used in the present invention is 1.6, f is the operating frequency; B m is the maximum value of the magnetic induction intensity on the hysteresis loop. The core volume of the single inductor impact magnet is very small, and the magnetic induction intensity is also very small, so the calculated core loss is also very small.

[0055] like Figure 8As shown, an embodiment of the present invention further provides a dual-bunch separation system, which includes a controller 2000, a charging power supply 3000, an auxiliary power supply 4000, a trigger 5000, a pulse power source 6000, a timer 7000 and the impact magnet system 1000 of the above embodiment, the controller 2000 is electrically connected to the charging power supply 3000, the auxiliary power supply 4000 and the pulse power source 6000 respectively, the charging power supply 3000 is electrically connected to the pulse power source 6000, the auxiliary power supply 4000 is electrically connected to the pulse power source 6000, the timer 7000 is electrically connected to the trigger 5000, the trigger 5000 is electrically connected to the pulse power source 6000, and the pulse power source 6000 is electrically connected to the impact magnet system 1000. The controller 2000 is used to control the charging power supply 3000, the auxiliary power supply 4000 and the pulse power source 6000 and monitor their working status. The charging power supply 3000 is used to charge the pulse power source 6000, the auxiliary power supply 4000 is used to power the pulse power source 6000, and the timer 7000 is used to send a timing signal to the trigger 5000. The trigger 5000 sends a trigger signal to the pulse power source 6000 according to the received timing signal to control the discharge of the pulse power source 6000 to form a pulse current. The pulse current is input to the coil 220 of the impact magnet 200 of the impact magnet system 1000, so that the impact magnet 200 changes the transmission path of the beam.

[0056] like Figure 9As shown, in some embodiments, the pulse power source 2000 includes a first resistor R1, a first diode D1, a second diode D2, a thyristor S1, a pulse forming line PFL, a third diode D3, a second resistor R2 and a capacitor C. The thyristor S1 has a trigger input positive terminal, a trigger input negative terminal, an auxiliary heating power supply positive terminal, an auxiliary heating power supply negative terminal, a thyristor anode terminal and a thyristor cathode terminal. One end of the charging power source 2000 is grounded, the other end of the charging power source 2000 is connected to one end of the first resistor R1, the other end of the first resistor R1 is connected to the anode of the first diode D1, the cathode of the first diode D1 is connected to the cathode of the second diode D2, the cathode of the thyristor S1, the first end of the pulse forming line PFL and one end of the capacitor C respectively, the anode of the second diode D2 is connected to the thyristor cathode terminal The anode terminal of the thyristor S1 is connected, the other end of the capacitor C is respectively connected to the first terminal 221 of the impact magnet 200 of the impact magnet system 1000 and the second end of the pulse forming line PFL, the second terminal 222 of the impact magnet 200 is grounded, the third end of the pulse forming line PFL is grounded, the fourth end of the pulse forming line PFL is connected to the cathode of the third diode D3, the anode of the third diode D3 is connected to one end of the second resistor R2, and the other end of the second resistor R2 is grounded; the positive terminal of the trigger 5000 is connected to the trigger input positive terminal of the thyristor S1, the negative terminal of the trigger 5000 is connected to the trigger input negative terminal of the thyristor S1, the positive terminal of the auxiliary power supply 4000 is connected to the auxiliary heating power supply positive terminal of the thyristor S1, and the negative terminal of the auxiliary power supply 4000 is connected to the auxiliary heating power supply negative terminal of the thyristor S1. By adding a capacitor C between the pulse forming line PFL and the impact magnet system 1000, the rise and fall times of the current can be greatly accelerated. The third diode D3 and the second resistor R2 can reduce the charging voltage of the pulse forming line PFL by half, thereby reducing the withstand voltage index and process requirements of the components. In particular, since the voltage value of the charging power supply 3000 is reduced by half, the cost of the charging power supply is greatly reduced.

[0057] The theoretical value of the accelerating capacitor C is: C = L M / 4Z0 2 , where L M is the sum of the magnet inductance and stray inductance, and Z0 is the characteristic impedance of the loop. Through PSpice program simulation, it was found that appropriately increasing the capacitance value can cause the discharge current to have an overshoot, while reducing the current fall time. The overshoot is selected to be less than 0.5% to determine the capacity of the acceleration capacitor. The simulation result shows that the capacitance value is 130pF. Figure 10 The figure shows the pulse current simulation waveform, which shows the corresponding pulse current waveforms when the capacitance is 100pF, 130pF and 160pF ​​respectively.

[0058] Theoretically, the current rise time is inversely proportional to the circuit's characteristic impedance, while the charging voltage is directly proportional to it. Therefore, the appropriate characteristic impedance must be selected to meet the required fall time while keeping the charging voltage low. Therefore, the pulse forming line (PFL) was chosen with a characteristic impedance of 50Ω and a current rise time of 70-80ns, meeting the required specifications, while the charging voltage was 10kV. Considering the design margin for peak current, if the peak current is increased by 20%, the charging voltage is 12kV. The current propagation time in the cable is approximately 5ns per meter, and the length of the PFL cable is 15m.

[0059] To achieve a satisfactory fast-pulse trapezoidal current waveform and the required edge time, distributed-parameter high-voltage, low-loss coaxial cable is used as the pulse-forming line, and a hydrogen thyratron is used as the discharge switch to minimize trigger jitter. Regarding layout, and for ease of maintenance, the charging power supply 3000 and auxiliary power supply 4000 are placed outside the tunnel, while the pulse power source 6000 is placed inside the beam tunnel and installed near the impact magnet system 1000. This minimizes the cable length of the discharge circuit and reduces electromagnetic interference caused by the pulse current.

[0060] The thyristor selected is the CX1154C from Teledyne E2V (Teledyne E2V Technology). It has a maximum forward peak voltage of 35kV, a maximum peak current of 3kA, an average current of 2A, a current rise rate of 100kA / μs, and a trigger jitter of less than 3ns, which can meet the power supply index requirements. The cooling method is air cooling, and the trigger of the thyristor is the MA2709A that matches the CX1154C.

[0061] The first resistor R1 and the first diode D1 can absorb reverse peak surge current, and the second diode D2 can absorb reverse voltage.

[0062] The charging power supply is required to be a constant current charging switching power supply with a maximum operating voltage of 20kV, which has local control and remote control functions. The charging power supply index requirements are as follows:

[0063] Maximum voltage: 20kV

[0064] Charging current: 10mA

[0065] Repeatability: <0.01%

[0066] The auxiliary power supply 4000 primarily provides AC heating for the thyratron filament and hydrogen generator, requiring long-term stability better than 0.5%. The thyratron hydrogen generator heating power supply requires 5V and 7.0A, while the filament heating power supply requires 6.3V and 22.5A. The power supply is turned on and off by a controller. The two power supplies are independently adjustable, with output powers of 200W and 50W, respectively. The voltage and current of each power supply are displayed, and signals indicating heating completion and power failure are output. Furthermore, a power supply operating time accumulation function is provided to calculate the thyratron lifespan.

[0067] Because rise and fall times are proportional to the magnet inductance and inversely proportional to the characteristic impedance of the pulse forming line (PFL), reducing these times requires minimizing the magnet's inductance when designing the magnet. When designing the pulse power source, minimize the discharge circuit's lead inductance and stray inductance. Using a single cable increases the PFL's characteristic impedance. However, these two parameters are subject to other constraints (such as the charging voltage) and cannot be simply increased or decreased.

[0068] Since the circuit scheme uses a high-voltage power supply for direct charging, the long-term stability of the magnet power supply depends on the long-term stability of the charging power supply. A high-voltage charging power supply with a long-term stability better than 0.01% is selected to ensure that the design indicators of long-term stability are achieved.

[0069] Since the pulse power source is placed on one side of the impact magnet in the tunnel, it is subject to the electromagnetic radiation of the beam, so it is necessary to avoid the direction of the beam during installation. When selecting components, its radiation resistance must be considered to increase the service life of the power supply.

[0070] Pulse power sources are a source of interference. When switched on, they generate strong electromagnetic interference, which can affect surrounding electronic equipment through ground loops and radiation. Therefore, measures must be taken to suppress electromagnetic interference. Enclosing the entire pulse power source in a well-grounded, shielded chassis can suppress electromagnetic radiation interference. Designing the main discharge circuit ensures that the pulse current returns to the ground flange, preventing discharge current from impacting the ground wire. Minimize the cable length of the discharge circuit to reduce electromagnetic radiation from the pulse current. Due to the skin effect of high-frequency current, both the pulse current cable and ground wire should use wide copper or multi-strand copper wire to increase the surface area of ​​the conductor. Components within the pulse power source should be grounded using a multi-point solution, connecting to the ground wire as close as possible. For high-voltage charging power supplies, strengthen filtering of the input power line to suppress conducted interference. Grounding for weak current and low-frequency circuits should be separated into power ground, signal ground, and shielded area, ultimately converging to a single ground point. All digital control and signal lines should be isolated with optical fiber (the trigger pulse circuit should be designed separately). Analog control and signal lines should use shielded cables and low-pass filtering.

[0071] In terms of structural design, two factors are mainly considered: one is the control of parasitic parameters, and the other is the suppression of electromagnetic emissions. Parasitic inductance will directly increase the operating voltage. Parasitic inductance and parasitic capacitance may also cause ripple in the output current and increase electromagnetic emissions. Parasitic parameters also have a negative impact on the reliability of the equipment and the repeatability of the waveform. The measures taken include: (1) using low leakage inductance devices, such as low-inductance coaxial capacitors and flat-plate press-fit switching devices; (2) using low leakage inductance connection structures, such as optimizing the layout to reduce the connection length and using wide copper plates for connection; (3) paying attention to the design of the boundary conditions of all discharge circuits, and trying to use a cavity-type closed structure to improve the distribution of the electromagnetic field when the equipment is working, thereby reducing the loop inductance and electromagnetic emissions.

[0072] The impact magnet system and dual-bunch separation system of the present invention are such that when the impact magnet system is not energized, the beam will be transmitted along a first path; when the impact magnet system is energized, the beam transmission path will change and be transmitted along a second path; the single-inductance impact magnet of the present invention can minimize the restriction of the magnet inductance on the leading and trailing edges of the pulse, and based on the energy storage of the pulse forming line PFL, a pulse power supply that quickly turns on the thyristor S1 to discharge is used to generate a pulse current, which can achieve dual-bunch separation with a minimum time interval of 100ns; the pulse current has a flat-top width, and therefore has good compatibility with dual-bunch separation with a time interval of 100ns-300ns; and the leading edge of the excitation pulse can be further improved by adding a capacitor C in the pulse discharge circuit.

[0073] It should be noted that the present invention (e.g., the inventive concept, etc.) has been described in the specification of this patent document and / or illustrated in the drawings based on exemplary embodiments; the embodiments of the present invention are presented only by way of example and are not intended to limit the scope of the invention. The structure and / or arrangement of the elements of the inventive concept embodied in the present invention as described in the specification and / or illustrated in the drawings is merely illustrative. Although exemplary embodiments of the present invention have been described in detail in this patent document, it is readily understood by those skilled in the art that equivalents, modifications, variations, etc. of the subject matter of the exemplary embodiments and alternative embodiments are possible and are considered to be within the scope of the present invention; all such subject matters (e.g., modifications, variations, embodiments, combinations, equivalents, etc.) are intended to be included within the scope of the present invention. It should also be noted that various / other modifications, changes, substitutions, equivalents, changes, omissions, etc. may be made in the configuration and / or arrangement of the exemplary embodiments (e.g., in terms of concept, design, structure, device, form, assembly, construction, means, function, system, process / method, step, order of process / method steps, operation, operating conditions, performance, materials, composition, combination, etc.) without departing from the scope of the present invention; all of these subjects (e.g., modifications, changes, embodiments, combinations, equivalents, etc.) are intended to be included within the scope of the present invention. The scope of the present invention is not intended to be limited to the subject matter described in the description and / or drawings of this patent document (e.g., details, structures, functions, materials, behaviors, steps, orders, systems, results, etc.). Considering that the claims of this patent document will be appropriately interpreted to cover the full scope of the subject matter of the present invention (e.g., including any and all such modifications, changes, embodiments, combinations, equivalents, etc.); it should be understood that the terminology used in this patent document is intended to provide a description of the subject matter of the exemplary embodiments, and not as a limitation on the scope of the present invention.

[0074] It should also be noted that, depending on the exemplary embodiments, the present invention may include conventional technologies (such as those implemented and / or integrated in the exemplary embodiments, modifications, variations, combinations, equivalents), or may include any other applicable technologies (present and / or future) that have the ability to perform the functions and processes / operations described in the specification and / or illustrated in the figures. All of these technologies (such as those implemented in embodiments, modifications, variations, combinations, equivalents, etc.) are considered to be within the scope of the present invention of this patent document.

Claims

1. A double bunch separation system, characterized in that: The invention comprises a controller, a charging power supply, an auxiliary power supply, a trigger, a pulse power source, a timer and an impact magnet system, wherein the controller is electrically connected to the charging power supply, the auxiliary power supply and the pulse power source respectively, the charging power supply is electrically connected to the pulse power source, the auxiliary power supply is electrically connected to the pulse power source, and the pulse power source is electrically connected to the impact magnet system; the impact magnet system comprises a vacuum chamber and an impact magnet fixed in the vacuum chamber, the impact magnet comprises a magnetic core, a coil and an outer frame, the magnetic core is fixed in the outer frame, the magnetic core has a window, and the coil is arranged in the window; a first connector is connected to a first end of the coil, a second connector is provided on a second end of the coil, and the first connector and the second connector extend outside the outer frame; a vacuum through-wall component electrode interface is provided on the vacuum chamber, the first connector and the second connector are electrically connected to the vacuum through-wall component electrode interface respectively; a beam outlet and a beam inlet are also provided on the vacuum chamber, and the beam inlet, the window and the beam outlet are connected in sequence; The pulse power source includes a first resistor, a first diode, a second diode, a thyristor, a pulse forming line, a third diode, a second resistor and a capacitor. One end of the charging power supply is grounded, the other end of the charging power supply is connected to one end of the first resistor, the other end of the first resistor is connected to the positive electrode of the first diode, the cathode of the first diode is respectively connected to the negative electrode of the second diode, the cathode end of the thyristor, the first end of the pulse forming line and one end of the capacitor; the anode of the second diode is connected to the anode end of the thyristor, and the other end of the capacitor is respectively connected to the impact magnet system. The first terminal of the impact magnet of the system is connected to the second end of the pulse forming line, the second terminal of the impact magnet is grounded, the third end of the pulse forming line is grounded, the fourth end of the pulse forming line is connected to the cathode of the third diode, the anode of the third diode is connected to one end of the second resistor, and the other end of the second resistor is grounded; the positive pole of the trigger is connected to the positive terminal of the trigger input of the thyristor, the negative pole of the trigger is connected to the negative terminal of the trigger input of the thyristor, the positive pole of the auxiliary power supply is connected to the positive terminal of the auxiliary power supply of the thyristor, and the negative pole of the auxiliary power supply is connected to the negative terminal of the auxiliary power supply of the thyristor.

2. The dual-bunch separation system according to claim 1, characterized in that: The vacuum chamber is also provided with an observation window and a vacuum gauge.

3. The dual-bunch separation system according to claim 1, characterized in that: The impact magnet system further includes a supporting mechanism, and the vacuum chamber is arranged on the supporting mechanism; the supporting mechanism is used to support the vacuum chamber and adjust the position of the vacuum chamber.

4. The dual-bunch separation system according to claim 3, characterized in that: An ion pump is provided on the supporting mechanism, and the ion pump is communicated with the interior of the vacuum chamber to evacuate the vacuum chamber.

5. The dual-bunch separation system according to claim 1, characterized in that: The coil includes a first wire, a second wire, a third wire, a first connecting plate and a second connecting plate. The first wire, the second wire and the third wire all extend along the beam transmission direction. The first wire is located on a first side, and the second wire and the second wire are located on a second side opposite to the first side. One end of the second wire forms the first end of the coil, and one end of the third wire forms the second end of the coil. The first end and the second end are arranged opposite to each other, the other end of the second wire is connected to the first connecting plate, and the other end of the third wire is connected to the second connecting plate. The two ends of the first wire are respectively connected to the first connecting plate and the second connecting plate.

6. The dual-bunch separation system according to claim 5, characterized in that: An insulating plate is provided between the first joint and the second joint.

7. The dual-bunch separation system according to claim 5, characterized in that: The magnetic core includes a first magnetic core, a second magnetic core and a third magnetic core, all of which extend along the beam transmission direction. The first magnetic core and the second magnetic core are arranged at intervals along the beam transmission direction. The third magnetic core is located between the first magnetic core and the second magnetic core. The first magnetic core, the third magnetic core and the second magnetic core have windows that are connected in sequence. The first joint and the second joint extend from the gap between the first magnetic core and the second magnetic core to outside the window.

8. The dual-bunch separation system according to claim 5, characterized in that: The outer frame includes a first frame, a second frame and a third frame. The first frame, the second frame and the third frame all extend along the beam transmission direction. The first frame is located on the first side, and the second frame and the third frame are located on the second side. The first frame is fixedly connected to the second frame and the third frame respectively. The magnetic core is clamped between the first frame and the second frame and the third frame; there is a gap between the second frame and the third frame for the first joint and the second joint to extend out.

9. The dual-bunch separation system according to claim 8, characterized in that: Heat dissipation holes are provided on the first wire, the second wire, the third wire, the first connecting plate, the second connecting plate, the first frame, the second frame and the third frame.

10. The dual-bunch separation system according to claim 1, characterized in that: At least one cooling belt is provided on the outer frame, and the cooling belt is connected to the inner wall of the vacuum chamber.

Images