A beam transformer and its installation method

Abstract

The present invention discloses a beam transformer and an installation method thereof. The beam transformer includes: a first flange, a second flange, a toroidal core coil, a ceramic gap ring, and a circumferential flat capacitor; an installation groove is provided between the first flange and the second flange, and the toroidal core coil, the circumferential flat capacitor, and the ceramic gap ring are arranged in the installation groove; the circumferential flat capacitor is arranged between the toroidal core coil and the ceramic gap ring; wherein, the circumferential flat capacitor is arranged on the outer circumference of the ceramic gap ring. By adopting the above technical solution, the circumferential flat capacitor is used to eliminate the interference of high-frequency interference signals on the measurement of microampere-level weak current and strong pulse beam current, improve the accuracy and reliability of detecting the intensity of the particle beam, and realize the measurement of the intensity of microampere-level pulsed beam current in a strong electromagnetic interference environment.

Description

Technical Field

[0001] The present invention relates to the technical field of beam measurement in particle accelerators, and particularly to a beam transformer and an installation method thereof. Background Art

[0002] A beam transformer is a non-intercepting detector used to detect the intensity of a particle beam in a particle accelerator. Its main body is a magnetic ring and a winding. The changing magnetic field of a pulsed beam will cause a change in the magnetic field intensity in the magnetic material. According to Faraday's law of electromagnetic induction, the beam is regarded as the primary winding of the transformer, and the winding of the magnetic ring is used as the secondary coil. The secondary coil induces a current signal. By connecting the two ends of the lead of the secondary coil to an ammeter or an amplifier circuit, the intensity and time structure of the pulsed beam can be measured.

[0003] When the existing beam transformer measures a weak current pulsed beam with a microampere-level intensity, the compact flange-type beam transformer only consists of a magnetic ring and a secondary winding inside. The high-frequency interference brought by the beam through the vacuum pipe or space through the cable will also be induced by the magnetic ring. The output signal of the secondary winding not only contains the real beam signal but also a large amount of interference signals and noise, resulting in a decrease in the signal-to-noise ratio of the probe and even an inability to perform effective detection. Summary of the Invention

[0004] The present invention provides a beam transformer and an installation method thereof, which can eliminate the interference of high-frequency interference signals on the measurement of a weak current pulsed beam with a microampere-level intensity, and improve the accuracy and reliability of detecting the intensity of a particle beam.

[0005] According to a first aspect of the present invention, there is provided a beam transformer, the beam transformer comprising: a first flange, a second flange, a toroidal core coil, a ceramic spacer ring, and a circular flat capacitor;

[0006] An installation groove is provided between the first flange and the second flange, and the toroidal core coil, the circular flat capacitor, and the ceramic spacer ring are disposed in the installation groove;

[0007] The circular flat capacitor is disposed between the toroidal core coil and the ceramic spacer ring; wherein, the circular flat capacitor is disposed on the outer circumference of the ceramic spacer ring.

[0008] Optionally, the circular flat capacitor includes a first metal layer, a first insulating layer, and a second metal layer;

[0009] The first insulating layer is interposed between the first metal layer and the second metal layer.

[0010] Optionally, the beam transformer further includes a second insulating layer;

[0011] The first metal layer is disposed between the first insulating layer and the annular core coil;

[0012] The second insulating layer is disposed between the ceramic spacer ring and the second metal layer.

[0013] Optionally, the first insulating layer and the second insulating layer are polyimide films.

[0014] Optionally, the first metal layer is welded to the second flange, and the second metal layer is welded to the first flange;

[0015] The projection of the first metal layer and the second metal layer in the first direction partially overlaps;

[0016] Wherein, the first direction is a direction perpendicular to the outer circumferential surface of the ceramic spacer ring.

[0017] Optionally, the width of the first insulating layer in the second direction is greater than the width of the first metal layer in the second direction, and the width of the first insulating layer in the second direction is greater than the width of the second metal layer in the second direction;

[0018] Wherein, the second direction is a direction parallel to the outer circumferential surface of the ceramic spacer ring.

[0019] Optionally, the annular core coil includes an annular core, a signal coil wound around the annular core, and a calibration coil wound around the annular core.

[0020] Optionally, the beam transformer further includes a base junction box, which is disposed on the annular outer surfaces of the first flange and the second flange and is electrically connected to the signal coil and the calibration coil;

[0021] The base junction box includes a four-core connector or a two-core connector;

[0022] The four-core connector includes a first connector and a second connector located on the surface of a semi-cylinder, and a third connector and a fourth connector located on the bottom surface of the base junction box. The positive and negative terminals of the signal coil and the positive and negative terminals of the calibration coil are electrically connected to the first connector, the second connector, the third connector, and the fourth connector respectively;

[0023] The two-core connector includes a fifth connector and a sixth connector coaxially distributed, and a seventh connector and an eighth connector coaxially distributed. The positive and negative terminals of the signal coil and the positive and negative terminals of the calibration coil are electrically connected to the fifth connector, the sixth connector, the seventh connector, and the eighth connector respectively.

[0024] According to a second aspect of the present invention, there is provided a method for installing a beam transformer, which is applied to the beam transformer described in any one of the first aspects. The beam transformer includes: a first flange, a second flange, a toroidal core coil, a ceramic gap ring, and a circumferential flat capacitor. The method for installing the beam transformer includes:

[0025] Weld the second flange to the ceramic gap ring;

[0026] Install the circumferential flat capacitor on the outer circumference of the ceramic gap ring;

[0027] Install the toroidal core coil on the outer circumference of the circumferential flat capacitor;

[0028] Fasten the first flange and the second flange together, and fasten the first flange and the second flange through screw perforations;

[0029] Weld the first flange to the ceramic gap ring.

[0030] Optionally, the circumferential flat capacitor includes a first metal layer, a first insulating layer, and a second metal layer. Installing the circumferential flat capacitor on the outer circumference of the ceramic gap ring includes:

[0031] Install the second metal layer on the outer circumference of the ceramic gap ring;

[0032] Install the first insulating layer on the outer circumference of the second metal layer;

[0033] Install the first metal layer on the outer circumference of the first insulating layer.

[0034] In the technical solution of the embodiment of the present invention, the first flange and the second flange are used as the housing of the beam transformer. An installation groove is provided in the housing between the first flange and the second flange. The toroidal core coil, the circumferential flat capacitor, and the ceramic gap ring are sequentially sleeved and distributed in the installation groove. Among them, the circumferential flat capacitor is arranged on the outer circumference of the ceramic gap ring, and the circumferential flat capacitor is arranged between the toroidal core and the ceramic gap ring. The circumferential flat capacitor is used to eliminate the interference of high-frequency interference signals on the measurement of microampere-level weak current strong pulse beam current, improve the accuracy and reliability of detecting the intensity of the particle beam current, and realize the measurement of the microampere-level pulse beam current intensity in a strong electromagnetic interference environment.

[0035] It should be understood that the content described in this part is not intended to identify the key or important features of the embodiments of the present invention, nor is it used to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] To more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0037] Figure 1 It is a schematic structural diagram of a beam transformer provided by the present invention;

[0038] Figure 2 It is a schematic partial structural diagram of a beam transformer provided by the present invention;

[0039] Figure 3 It is a schematic structural diagram of another beam transformer provided by the present invention;

[0040] Figure 4 It is a schematic partial structural diagram of another beam transformer provided by the present invention;

[0041] Figure 5 It is a schematic partial structural diagram of another beam transformer provided by the present invention;

[0042] Figure 6 It is a schematic partial structural diagram of another beam transformer provided by the present invention;

[0043] Figure 7 It is a schematic partial structural diagram of another beam transformer provided by the present invention;

[0044] Figure 8 It is a schematic partial structural diagram of another beam transformer provided by the present invention;

[0045] Figure 9 It is a flowchart of an installation method of a beam transformer provided by the present invention;

[0046] Figure 10 It is a flowchart of another installation method of a beam transformer provided by the present invention. Detailed implementation manners

[0047] To enable those skilled in the art to better understand the solutions of the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0048] It should be noted that the terms "first", "second", etc. in the specification, claims and the above-mentioned drawings of the present invention are used to distinguish similar objects, and do not necessarily have to be used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances, so that the embodiments of the present invention described here can be implemented in an order other than those illustrated or described here. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device comprising a series of steps or units does not have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0049] It should be understood that various forms of the processes shown above can be used, reordering, adding or deleting steps. For example, the steps recited in the present invention can be executed in parallel, sequentially or in a different order, as long as the desired results of the technical solution of the present invention can be achieved, and no limitation is made herein.

[0050] Embodiment 1

[0051] Figure 1 is a schematic structural diagram of a beam transformer provided according to the present invention; Figure 2 is a partial structural diagram of a beam transformer provided according to the present invention. This embodiment is applicable to a particle accelerator and is used to detect the intensity of a particle beam. Refer to Figure 1 and Figure 2 According to the present invention, the beam transformer 100 provided in the embodiment of the present invention includes: a first flange 1, a second flange 2, a toroidal core coil 3, a ceramic gap ring 4, and a circumferential flat capacitor 5; an installation groove 6 is provided between the first flange 1 and the second flange 2, and the toroidal core coil 3, the circumferential flat capacitor 5, and the ceramic gap ring 4 are arranged in the installation groove 6; the circumferential flat capacitor 5 is arranged between the toroidal core coil 3 and the ceramic gap ring 4.

[0052] Among them, the circumferential flat capacitor 5 is arranged on the outer circumference of the ceramic gap ring 4. The beam transformer is a non-intercepting detector used in a particle accelerator to detect the intensity of a particle beam and is used to monitor the pulsed beam current passing through an acceleration pipe. Its main body is a magnetic ring and winding. When a beam passes through the magnetic ring, the pulsed beam-changing magnetic field will cause a change in the magnetic field intensity in the magnetic material. Regarding the beam as the primary winding of a transformer and the magnetic ring winding as the secondary coil, a current signal is induced in the secondary coil. Connecting the two ends of the lead of the secondary coil to an ammeter or an amplification circuit can be used to measure the intensity and time structure of the pulsed beam, ensuring the normal operation of the accelerator and optimizing its performance.

[0053] Specifically, the beam transformer 100 includes a first flange 1 and a second flange 2. The first flange 1 and the second flange 2 can be buckled with each other to form the housing of the beam transformer 100. An installation groove 6 is provided inside the housing. The installation groove 6 is used to install the toroidal core coil 3, the circumferential flat capacitor 5 and the ceramic spacer ring 4. The toroidal core coil 3, the circumferential flat capacitor 5 and the ceramic spacer ring 4 are distributed in a nested manner inside the installation groove. The circumferential flat capacitor 5 is arranged on the outer circumference of the ceramic spacer ring 4, and the toroidal core coil 3 is arranged on the outer circumference of the circumferential flat capacitor 5. Since the beam in the charged particle accelerator generally flies in an ultra-high vacuum pipeline, the flange-type beam transformer 100 is also an ultra-high vacuum component. Therefore, the ceramic spacer ring 4 is arranged at the inner circumference of the beam transformer 100. After the ceramic spacer ring 4 is welded to the first flange 1 and the second flange 2, the inner circumference of the ceramic spacer ring 4 and the installation groove 6 form a closed chamber to maintain the ultra-high vacuum of the beam flight pipeline and the beam transformer 100. At the same time, when the particle beam passes through the cylindrical channel (equivalent to the primary coil) inside the beam transformer 100, the toroidal core coil 3 (equivalent to the secondary coil) can sense the change of the electromagnetic field of the beam, realizing the monitoring of the pulsed beam passing through the acceleration pipeline.

[0054] In an alternative embodiment, both the first flange 1 and the second flange 2 are standard CF interface flanges, and the shortest longitudinal space is 40 mm.

[0055] It can be understood that when measuring the weak current and strong pulsed beam of microampere level through the beam transformer 100, in a complex electromagnetic environment, especially in the synchrotron tunnel with strong pulsed electromagnetic interference where the beam transformer 100 works, the high-frequency interference signals brought by the beam through the vacuum pipeline will also be sensed by the magnetic ring. The output signal of the toroidal core coil not only contains the real beam signal, but also contains a large number of high-frequency interference signals, resulting in a decrease in the signal-to-noise ratio of the probe and even an inability to effectively detect the beam. Therefore, the circumferential flat capacitor 5 is arranged between the toroidal core coil 3 and the ceramic spacer ring 4 to function as a bypass filter capacitor. According to the frequency range of the high-frequency interference signals, the capacitance value of the circumferential flat capacitor 5 is designed to provide a low-impedance mirror path for the high-frequency interference signals. The formed high-frequency mirror current is the same size as the high-frequency part in the beam but in the opposite direction, so as to cancel the high-frequency part in the beam, making the current finally sensed by the beam transformer 100 be the low-frequency part in the beam spectrum and realizing the accurate measurement of the weak current and strong pulsed beam of microampere level.

[0056] In the embodiment of the present invention, the first flange and the second flange are used as the housing of the beam transformer. An installation groove is provided in the housing between the first flange and the second flange. The annular core coil, the circumferential flat capacitor, and the ceramic gap ring are sequentially sleeved and distributed in the installation groove. Among them, the circumferential flat capacitor is arranged on the outer circumference of the ceramic gap ring, and the circumferential flat capacitor is arranged between the annular core and the ceramic gap ring. The circumferential flat capacitor is used to eliminate the interference of high-frequency interference signals on the measurement of microampere-level weak current and strong pulse beam current, improve the accuracy and reliability of detecting the intensity of the particle beam current, and realize the measurement of microampere-level pulse beam current intensity in a strong electromagnetic interference environment.

[0057] Optionally, the circumferential flat capacitor 5 includes a first metal layer 51, a first insulating layer 7, and a second metal layer 52; the first insulating layer 7 is between the first metal layer 51 and the second metal layer 52.

[0058] Specifically, referring to Figure 2 , the circumferential flat capacitor 5 is composed of a first metal layer 51 and a second metal layer 52 that are parallel to each other, and a first insulating layer 7. The first metal layer 51 and the second metal layer 52 have good electrical conductivity and can provide a low-impedance mirror path for high-frequency interference signals to form a high-frequency mirror current through the circumferential flat capacitor 5, thereby canceling the high-frequency part in the beam current. The first insulating layer 7 is between the first metal layer 51 and the second metal layer 52 and is used to isolate the charges on the two metal layers to prevent the first metal layer 51 and the second metal layer 52 from making direct contact, thereby avoiding the occurrence of a short-circuit phenomenon inside the capacitor, helping to extend the service life of the capacitor, and reducing the failures and maintenance costs caused by short circuits.

[0059] Exemplarily, the materials of the first metal layer 51 and the second metal layer 52 can be copper, aluminum, etc.; the material of the first insulating layer 7 can be ceramic, polymer film, etc. It should be noted that as long as the corresponding functions of the circumferential flat capacitor 5 can be realized, the types of materials of the first metal layer 51, the first insulating layer 7, and the second metal layer 52 are not specifically limited in this embodiment.

[0060] Optionally, the beam transformer 100 further includes a second insulating layer 8; the first metal layer 51 is between the first insulating layer 7 and the annular core coil 3; the second insulating layer 8 is between the ceramic gap ring 4 and the second metal layer 52.

[0061] Specifically, referring to Figure 3, the first metal layer 51 is disposed between the first insulating layer 7 and the annular core coil 3; the second insulating layer 8 is disposed between the ceramic gap ring 4 and the second metal layer 52, which can effectively isolate the direct contact between the ceramic gap ring 4 and the circular flat capacitor 5, prevent short circuits inside the ceramic gap ring 4 and the circular flat capacitor 5, and thus ensure the safety and stability of the circular flat capacitor 5 during normal operation.

[0062] Optionally, the first insulating layer 7 and the second insulating layer 8 are polyimide films.

[0063] Specifically, as can be seen from the above, the circular flat capacitor 5 is used to provide a low-impedance mirror path for high-frequency interference signals, and the current it carries is mostly high-frequency current. The polyimide film has the characteristics of high breakdown strength, low dielectric constant, and high corona resistance. Using the polyimide film as the material of the first insulating layer 7 and the second insulating layer 8, its dielectric constant is 3.5, which makes it have a lower capacitance under high-frequency voltage, helping to improve the working efficiency of the beam transformer; at the same time, the polyimide film can remain stable under high-frequency voltage, effectively preventing corona discharge and breakdown phenomena, ensuring the safe operation of the beam transformer, and reducing the maintenance frequency and cost of the beam transformer.

[0064] Optionally, the first metal layer 51 is welded to the second flange 2, and the second metal layer 52 is welded to the first flange 1; the projected portions of the first metal layer 51 and the second metal layer 52 overlap in the first direction X; wherein, the first direction X is the direction perpendicular to the outer circumferential surface of the ceramic gap ring 4.

[0065] Specifically, referring to Figures 1 to 3 , the first metal layer 51 is welded to the second flange 2 and insulated from the first flange 1 at the same time; the second metal layer 52 is welded to the first flange 1 and insulated from the second flange at the same time, that is, the projected portions of the first metal layer 51 and the second metal layer 52 in the first direction X perpendicular to the outer circumferential surface of the ceramic gap ring 4 overlap. Exemplarily, the first direction can be the radial direction of the first flange and / or the second flange.

[0066] In an alternative embodiment, the thickness of the first insulating layer 7, the relative dielectric constant of the first insulating layer 7, and the overlapping area of the projections of the first metal layer 51 and the second metal layer 52 in the first direction X determine the capacitance of the circular flat capacitor. The specific calculation formula is:

[0067] S = Cd / ε r ε0

[0068] wherein, S is the overlapping area of the projections of the first metal layer 51 and the second metal layer 52 in the first direction X, C is the capacitance value of the circular flat capacitor, d is the thickness of the first insulating layer, and ε ris the relative permittivity of the first insulating layer, and ε0 is the permittivity of free space.

[0069] Specifically, continue to refer to Figure 3 According to the frequency range of the high-frequency interference signals in the beam current, the capacitance value C of the circular flat capacitor 5 is designed. Then, according to the above calculation formula, in the installation groove 7 formed by the buckling of the first flange 1 and the second flange 2, the thickness of the first insulating layer 7 and the overlapping area of the projections of the first metal layer 51 and the second metal layer 52 in the first direction X are adjusted, so as to specifically cancel the high-frequency part in the beam current, and the application flexibility and adaptability of the beam current transformer are improved.

[0070] Optionally, the width of the first insulating layer 7 in the second direction Y is greater than the width of the first metal layer 51 in the second direction Y, and the width of the first insulating layer 7 in the second direction Y is greater than the width of the second metal layer 52 in the second direction Y; wherein, the second direction Y is the direction parallel to the outer circumferential surface of the ceramic gap ring 4.

[0071] Specifically, continue to refer to Figure 3 In the second direction Y parallel to the outer circumferential surface of the ceramic gap ring 4, the width of the first insulating layer 7 of the circular flat capacitor 5 is greater than the widths of the first metal layer 51 and the second metal layer 52 in the second direction Y parallel to the outer circumferential surface of the ceramic gap ring 4. The wider first insulating layer 7 can more effectively isolate the first metal layer 51 and the second metal layer 52, prevent them from directly contacting, thereby avoiding the occurrence of short-circuit phenomena, and helping to maintain the stability of the electric field between the first metal layer 51 and the second metal layer 52. At the same time, the wider first insulating layer 7 can increase the overall tensile strength of the circular flat capacitor 5, making it more stable when subjected to external forces, and helping to improve the seismic performance of the beam current transformer. Exemplarily, the second direction can be the axial direction of the first flange and / or the second flange.

[0072] Optionally, the toroidal core coil 3 includes a toroidal core 31, a signal coil 32 wound around the toroidal core 31, and a calibration coil 33 wound around the toroidal core 31.

[0073] Among them, the number of turns of the signal coil 32 can be N, where N is a natural number greater than 1; the number of turns of the calibration coil 33 can be 1, and the embodiments of the present invention do not make specific limitations thereon.

[0074] Specifically, refer to Figure 4, when the charged beam passes through the beam transformer 100, it will change the magnetic flux in the toroidal core, thereby causing an induced electromotive force to be generated in the signal coil 32. The magnitude of the induced electromotive force is proportional to the intensity of the beam. By connecting the positive terminal and negative terminal of the signal coil 32, the induced electromotive force is led out from the signal coil 32 and connected to an ammeter or an amplifier circuit, which can be used to measure the intensity and time structure of the pulsed beam, and realize the measurement of the intensity of the charged beam. A calibration coil 33 is added. By energizing the calibration coil 33, a standard magnetic field with a known intensity is generated. When the standard magnetic field acts on the beam transformer 100, an induced electromotive force will be generated inside it. The induced electromotive force is amplified by a preamplifier and converted into a digital signal for recording. If it is found that the response of the beam transformer is inconsistent with the standard magnetic field, the source of the systematic error can be identified, and then the measurement result can be corrected through a software algorithm to improve the accuracy of calibration and realize the calibration of the beam transformer.

[0075] Optionally, the beam transformer 100 further includes a base joint box 9. The base joint box 9 is provided on the annular outer surface of the first flange 1 and the second flange 2 and is electrically connected to the signal coil 32 and the calibration coil 33; the base joint box 9 includes a four-core joint or a two-core joint; the four-core joint includes a first joint 91 and a second joint 92 located on the surface of the semi-cylindrical body, and a third joint 93 and a fourth joint 94 located on the bottom surface of the base joint box 9. The positive terminal and negative terminal of the signal coil 32 and the positive terminal and negative terminal of the calibration coil 33 are respectively electrically connected to the first joint 91, the second joint 92, the third joint 93 and the fourth joint 94; the two-core joint includes a fifth joint 95 and a sixth joint 96 coaxially distributed, and a seventh joint 97 and an eighth joint 98 coaxially distributed. The positive terminal and negative terminal of the signal coil 32 and the positive terminal and negative terminal of the calibration coil 33 are respectively electrically connected to the fifth joint 95, the sixth joint 96, the seventh joint 97 and the eighth joint 98.

[0076] Specifically, referring to Figures 1 to 7 , the base joint box 9 is riveted on the annular outer surface of the first flange 1 and the second flange 2. The base joint box 9 can be a four-core joint, such as Figure 5 and Figure 6As shown, the base connection box 9 has four groups of connectors, namely the first connector 91 and the second connector 92 located on the surface of the semi-cylindrical body, and the third connector 93 and the fourth connector 94 located on the bottom surface of the base connection box 9. The signal coil 32 and the calibration coil 33 lead out four connection terminals, and each connector of the base connection box 9 is electrically connected to a connection terminal respectively, realizing the external transmission of the beam current transformer signal coil 32 and the calibration coil 33. Exemplarily, the positive connection terminal of the signal coil 32 is electrically connected to the first connector 91, the negative connection terminal of the signal coil 32 is electrically connected to the second connector 92, the positive connection terminal of the calibration coil 33 is electrically connected to the third connector 93, and the negative connection terminal of the calibration coil 33 is electrically connected to the fourth connector 94.

[0077] Alternatively, the base connection box 9 can be a two-core connector, such as Figure 1 and Figure 7 As shown, the base connection box 9 has two groups of connector groups with two connectors coaxially distributed, namely the connector group including the fifth connector 95 and the sixth connector 96 coaxially distributed, and the connector group including the seventh connector 97 and the eighth connector 98 coaxially distributed. The signal coil 32 and the calibration coil 33 lead out four connection terminals. The positive connection terminal and the negative connection terminal of the signal coil 32 are electrically connected to the connector group with two connectors coaxially distributed of the base connection box 9, and the positive connection terminal and the negative connection terminal of the calibration coil 33 are electrically connected to the other connector group with two connectors coaxially distributed of the base connection box 9. Among them, each connector of the base connection box 9 is electrically connected to a connection terminal respectively, realizing the external transmission of the beam current transformer signal coil 32 and the calibration coil 33. Exemplarily, the positive connection terminal of the signal coil 32 is electrically connected to the fifth connector 95, the negative connection terminal of the signal coil 32 is electrically connected to the sixth connector 96, the positive connection terminal of the calibration coil 33 is electrically connected to the seventh connector 97, and the negative connection terminal of the calibration coil 33 is electrically connected to the eighth connector 98.

[0078] Optionally, the beam current transformer 100 further includes a magnetic shielding part 10; the magnetic shielding part 10 is arranged in the installation groove 6 and wraps the annular magnetic core coil 3; wherein, the magnetic shielding part 10 includes a first sub-magnetic shielding part 101 and a second sub-magnetic shielding part 102, and the inner circumferential diameter of the second sub-magnetic shielding part 102 is greater than the outer circumferential diameter of the first sub-shielding part 101.

[0079] Specifically, referring to Figure 1 and Figure 8, the first sub-shielding part 101 is buckled on one side of the toroidal core coil 3, the second sub-shielding part 102 is buckled on the other side of the toroidal core coil 3, and the inner circumferential diameter of the second sub-magnetic shielding part 102 is greater than the outer circumferential diameter of the first sub-shielding part 101, so that the shielding part 10 formed by the first sub-shielding part 101 and the second sub-shielding part 102 can wrap the toroidal core coil 3, which can stabilize the magnetic field environment inside the toroidal core coil 3, reduce the measurement error caused by the change of the external magnetic field, and improve the accuracy of beam current intensity measurement. Exemplarily, the shielding part 10 can be a butt-jointed permalloy magnetic shielding box, and the present invention does not make specific limitations thereto.

[0080] Optionally, the beam current transformer 100 further includes: a first kovar ring 11 and a second kovar ring 12; the ceramic spacer ring 4 is welded to the first flange 1 based on the first kovar ring 11; the ceramic spacer ring 4 is welded to the second flange 2 based on the second kovar ring 12.

[0081] Specifically, continue to refer to Figure 1 , the first kovar ring 11 and the second kovar ring 12 provide necessary physical support for the ceramic spacer ring, ensuring its stable installation in the beam current transformer 100. While ensuring that the inside of the beam current transformer 100 is in an ultra-high vacuum, the first kovar ring 11 and the second kovar ring 12 as connecting parts also have an electromagnetic shielding function, which can prevent the influence of electromagnetic interference on the internal components of the beam current transformer. Exemplarily, the materials of the first kovar ring 11 and the second kovar ring 12 can be ceramics, 4J33, etc., and the present embodiment does not make specific limitations thereto.

[0082] Embodiment 2

[0083] Figure 9 is a flowchart of an installation method of a beam current transformer according to the present invention. This method is applied to the beam current transformer provided by the present invention. The beam current transformer includes: a first flange, a second flange, a toroidal core coil, a ceramic spacer ring, and a circumferential flat capacitor. Refer to Figure 9 , the installation method of the beam current transformer includes:

[0084] S1. Weld the second flange to the ceramic spacer ring;

[0085] S2. Install the circumferential flat capacitor on the outer circumference of the ceramic spacer ring;

[0086] S3. Install the toroidal core coil on the outer circumference of the circumferential flat capacitor;

[0087] S4. Buckle the first flange and the second flange, and fasten the first flange and the second flange by perforating with screws;

[0088] S5. Weld the first flange to the ceramic spacer ring.

[0089] Specifically, the housing of the beam transformer consists of a first flange and a second flange. The ceramic gap ring, the circumferential flat capacitor, and the toroidal core coil are all installed in the installation groove formed by the buckling of the first flange and the second flange. After welding the ceramic gap ring to the installation groove of the second flange, the circumferential flat capacitor is installed on the outer circumference of the ceramic gap ring, and then the toroidal core coil is installed on the outer circumference of the circumferential flat capacitor. Thus, a structure of the ceramic gap ring, the circumferential flat capacitor, and the toroidal core coil that are sequentially sleeved inside the installation groove is obtained. Buckle the first flange and the second flange that have completed the internal installation, and fasten the first flange and the second flange through screw perforation to complete the assembly of the housing of the beam transformer. Finally, on the inner circumference of the beam transformer, weld the ceramic gap ring to the first flange to ensure the ultra-high vacuum inside the beam transformer. After the welding is completed, use a clean non-woven fabric to dip an appropriate amount of anhydrous ethanol or acetone to wipe off the welding marks at the weld.

[0090] In the embodiment of the present invention, the first flange and the second flange are used as the housing of the beam transformer. An installation groove is provided in the housing between the first flange and the second flange. The toroidal core coil, the circumferential flat capacitor, and the ceramic gap ring are sequentially and circumferentially distributed in the installation groove. Among them, the circumferential flat capacitor is arranged on the outer circumference of the ceramic gap ring, and the circumferential flat capacitor is arranged between the toroidal core and the ceramic gap ring. The circumferential flat capacitor is used to eliminate the interference of high-frequency interference signals on the measurement of the microampere-level weak current and strong pulse beam current, improve the accuracy and reliability of detecting the particle beam current intensity, and realize the measurement of the microampere-level pulse beam current intensity in a strong electromagnetic interference environment.

[0091] Optionally, the circumferential flat capacitor includes a first metal layer, a first insulating layer, and a second metal layer. Refer to Figure 10 , and installing the circumferential flat capacitor on the outer circumference of the ceramic gap ring includes:

[0092] S21. Install the second metal layer on the outer circumference of the ceramic gap ring;

[0093] S22. Install the first insulating layer on the outer circumference of the second metal layer;

[0094] S23. Install the first metal layer on the outer circumference of the first insulating layer.

[0095] Specifically, the circumferential flat capacitor is composed of a first metal layer, a first insulating layer, and a second metal layer. Along the direction away from the outer circumference of the ceramic gap ring, the second metal layer, the first insulating layer, and the first metal layer are sequentially arranged.

[0096] Note that the above is only a preferred embodiment of the present invention and the technical principles applied. Those skilled in the art will understand that the present invention is not limited to the specific embodiments here, and various obvious changes, re-adjustments, combinations with each other and substitutions can be made by those skilled in the art without departing from the protection scope of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments only. Without departing from the concept of the present invention, more other equivalent embodiments can be included, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A beam current transformer, characterized in that: The beam transformer comprises: a first flange, a second flange, a ring-shaped magnetic core coil, a ceramic gap ring and a circumferential flat plate capacitor; A mounting groove is provided between the first flange and the second flange, and the annular magnetic core coil, the circumferential plate capacitor and the ceramic gap ring are arranged in the mounting groove; The circumferential flat plate capacitor is arranged between the annular magnetic core coil and the ceramic gap ring; wherein the circumferential flat plate capacitor is arranged on the outer circumference of the ceramic gap ring.

2. The beam current transformer according to claim 1, characterized in that: The circumferential flat plate capacitor comprises a first metal layer, a first insulating layer and a second metal layer; The first insulating layer is between the first metal layer and the second metal layer.

3. The beam current transformer according to claim 2, characterized in that: The beam current transformer also includes a second insulating layer; The first metal layer is between the first insulating layer and the toroidal magnetic core coil; The second insulating layer is between the ceramic gap ring and the second metal layer.

4. The beam current transformer according to claim 3, characterized in that: The first insulating layer and the second insulating layer are polyimide films.

5. The beam current transformer according to claim 2, characterized in that: The first metal layer is welded to the second flange, and the second metal layer is welded to the first flange; The projections of the first metal layer and the second metal layer in the first direction partially overlap; Wherein, the first direction is a direction perpendicular to the outer circumferential surface of the ceramic gap ring.

6. The beam current transformer according to claim 2, characterized in that: The width of the first insulating layer in the second direction is greater than the width of the first metal layer in the second direction, and the width of the first insulating layer in the second direction is greater than the width of the second metal layer in the second direction; Wherein, the second direction is a direction parallel to the outer circumferential surface of the ceramic gap ring.

7. The beam current transformer according to claim 1, characterized in that: The toroidal core coil comprises a toroidal core, a signal coil wound around the toroidal core, and a calibration coil wound around the toroidal core.

8. The beam current transformer according to claim 7, characterized in that: The beam current transformer further comprises a base joint box, which is arranged on the annular outer surface of the first flange and the second flange and is electrically connected to the signal coil and the calibration coil; The base connector box includes a four-core connector or a two-core connector; The four-core connector includes a first connector and a second connector located on the surface of the semi-cylinder, and a third connector and a fourth connector located on the bottom surface of the base connector box, and the positive connector and the negative connector of the signal coil and the positive connector and the negative connector of the calibration coil are electrically connected to the first connector, the second connector, the third connector and the fourth connector respectively; The two-core connector includes a fifth connector and a sixth connector that are coaxially distributed, and a seventh connector and an eighth connector that are coaxially distributed. The positive terminal and the negative terminal of the signal coil and the positive terminal and the negative terminal of the calibration coil are electrically connected to the fifth connector, the sixth connector, the seventh connector and the eighth connector, respectively.

9. A method for installing a beam transformer, characterized in that: Applied to the beam transformer according to any one of claims 1 to 8, the beam transformer comprises: a first flange, a second flange, a ring-shaped magnetic core coil, a ceramic gap ring and a circumferential flat plate capacitor, and the installation method of the beam transformer comprises: Welding the second flange to the ceramic gap ring; The circumferential plate capacitor is installed on the outer circumference of the ceramic gap ring; Install the annular magnetic core coil on the outer circumference of the circumferential flat plate capacitor; The first flange and the second flange are buckled together, and the first flange and the second flange are fastened by screws through holes; The first flange is welded to the ceramic gap ring.

10. The method for installing a beam current transformer according to claim 9, characterized in that: The circumferential flat plate capacitor comprises a first metal layer, a first insulating layer and a second metal layer, and the circumferential flat plate capacitor is mounted on the outer circumference of the ceramic gap ring and comprises: Installing the second metal layer on the outer circumference of the ceramic gap ring; Installing the first insulating layer on the outer circumference of the second metal layer; The first metal layer is installed on the outer circumference of the first insulating layer.

Images