Particle accelerator feeding isolation device and method

Abstract

The present invention discloses a particle accelerator feed isolation device and method, including: a feed tube; the feed tube includes: an external feed group, including an external feed line; an internal feed group, including two sections of internal feed lines that are connected to each other, namely internal feed one and internal feed two that are connected to the internal feed one; an isolation layer, arranged between the two sections of internal feed lines that are connected to each other; a stopper structure, arranged at the connection of the two sections of internal feed lines that are connected to each other, including an insulating stopper ring. The present invention achieves DC isolation of the inner core of the feed tube on the power source side and the acceleration cavity side by designing an isolation layer between the inner feed one and the inner feed two that are connected to the inner feed one, thereby avoiding the problem that the bias voltage of the coupler will be introduced into the inner core of the power source feed tube.

Description

Technical Field

[0001] The present invention relates to the field of particle accelerator feed isolation, and in particular to a particle accelerator feed isolation device and method. Background Art

[0002] Electromagnetic field accelerators use alternating electromagnetic fields to accelerate charged particles. The alternating electromagnetic field can be a magnetic induction field or an alternating radio frequency field.

[0003] High-frequency acceleration technology can be used to realize various forms of accelerator equipment such as cyclotron, synchrocyclotron, and linear accelerator.

[0004] The secondary electron multiplication effect on the output window refers to the electrons that are field-emitted by some free electrons in a vacuum or window under a high-frequency field strength. These electrons hit the window under the acceleration of the high-frequency field. Due to the secondary electron emission of the window, many times more secondary electrons than primary electrons are emitted. The emitted secondary electrons absorb the energy of the high-frequency field, and their motion trajectories are bent. They come back to hit the window and emit more secondary electrons, thus forming a vicious circle.

[0005] The bombardment of electrons will also cause a large amount of gas to be released from the coupling window, causing the vacuum condition inside the acceleration cavity to deteriorate, increasing the possibility of arc discharge, and forming a large reflection signal for high-frequency feed.

[0006] The energy of electrons bombarding the window is released and consumed in the form of kinetic energy and heat energy, which will cause a sharp increase in the local temperature of the coupling window and produce glow, which may cause damage to the coupling window;

[0007] There are many ways to suppress the secondary electron multiplication of the coupler.

[0008] One of them is a method of suppressing secondary electrons by using a bias voltage.

[0009] The emission of secondary electrons is suppressed by increasing the bias voltage between the inner and outer conductors of the coupler.

[0010] However, the connection between the coupler and the feeder is a direct connection.

[0011] The cavity vacuum and the external atmospheric environment are isolated by a coupler.

[0012] This direct connection relationship brings about the problem that the bias voltage of the coupler will be introduced into the core of the power source feed tube. Summary of the invention

[0013] Purpose of the invention: To provide a particle accelerator feeding isolation device and method to solve the above problems existing in the prior art.

[0014] Technical solution: A particle accelerator feed isolation device, comprising:

[0015] Feeder;

[0016] Characterized in that the feed pipe comprises:

[0017] An external feed group, including an external feed line;

[0018] The internal feed group includes two sections of internal feed lines connected to each other, namely, internal feed one and internal feed two connected to the internal feed one;

[0019] An isolation layer is provided between two sections of inner feeder lines butted against each other;

[0020] The stop structure is arranged at the joint of two sections of inner feeder lines that are butted against each other, and comprises an insulating stop ring.

[0021] The present invention realizes DC isolation of the feeding tube inner core on the power source side and the accelerating cavity side by designing an isolation layer between the inner feed one and the inner feed two connected to the inner feed one, thereby avoiding the problem that the bias voltage of the coupler will be introduced into the inner core of the power source feeding tube.

[0022] In a further embodiment, the second internal feedback is connected to a high voltage bias circuit.

[0023] In a further embodiment, the isolation layer is composed of a polyimide film.

[0024] In a further embodiment, feeder line support flanges are provided at the ends of the internal feed one and the internal feed two.

[0025] A particle accelerator feed isolation method, comprising:

[0026] The electrical connection between the power source and the cavity is achieved by using a coaxial feed-in method with an external high voltage bias circuit;

[0027] The DC isolation between the power source side and the accelerating cavity side is realized by using a double inner-feed sleeve wrapped with a high-isolation insulating material; a typical high-insulation material may be polyimide;

[0028] Design the length and thickness of the insulation material according to the voltage and insulation distance requirements;

[0029] A tight winding method is selected to achieve a tight connection between the insulating material and the inner feed one and the inner feed two, and to achieve DC isolation.

[0030] For the terminal between the inner feed one and the inner feed two, a material suitable for high frequency electric field and with low loss is designed to fix the terminal between the inner feed one and the inner feed two;

[0031] Thereby, a reliable microwave connection and a reliable high-voltage isolation structure are achieved between the accelerator cavity and the power source.

[0032] Beneficial effect: The present invention discloses a particle accelerator feed isolation device and method. The present invention achieves DC isolation of the inner core of the feed tube on the power source side and the acceleration cavity side by designing an isolation layer between the inner feed one and the inner feed two connected to the inner feed one, thereby avoiding the problem that the bias voltage of the coupler will be introduced into the inner core of the power source feed tube. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a structural schematic diagram of the present invention.

[0034] Figure 2 It is a schematic diagram of the structure of the feed-in isolation device of the present invention.

[0035] Figure 3 It is a partially enlarged schematic diagram of the feed-in isolation device of the present invention.

[0036] Figure 4 It is a typical example diagram of the feed-in isolation device of the present invention.

[0037] Figure 5 This is a schematic diagram of the principle of the high-frequency feed system.

[0038] Figure 6 This is a schematic diagram of a standard feed tube. DETAILED DESCRIPTION

[0039] The present application relates to a particle accelerator feed isolation device and method, which is explained in detail below through specific implementation methods.

[0040] The secondary electron multiplication effect on the output window refers to the electrons that are field-emitted by some free electrons in a vacuum or the window under a high-frequency field strength. These electrons bombard the window under the acceleration of the high-frequency field. Due to the secondary electron emission of the window, it will emit many times more secondary electrons than the primary electrons. The emitted secondary electrons absorb the energy of the high-frequency field, and their motion trajectories bend, and they come back to bombard the window, emitting more secondary electrons, thus forming a vicious circle.

[0041] The bombardment of electrons will also cause the coupling window to release a large amount of gas, causing the vacuum condition inside the accelerating cavity to deteriorate, increasing the possibility of arc discharge, and forming a large reflection signal for high-frequency input. The energy of electrons bombarding the window is released and consumed in the form of kinetic energy and thermal energy, which will cause the local temperature of the coupling window to rise sharply and produce glow. This may cause damage to the coupling window.

[0042] The high-frequency feed power of modern accelerators is usually high, and they are high-power couplers. The couplers are mainly composed of ceramic windows, inner and outer conductors, and coupling rings.

[0043] A coaxial feed tube is used to achieve power transmission from the power source to the accelerating cavity coupler. Typical coaxial feed tube sizes include 1-7 / 8, 3-1 / 8, 4-1 / 2, 6-1 / 8, etc.)

[0044] There are many ways to suppress the secondary electron multiplication of the coupler.

[0045] One of them is a method of suppressing secondary electrons by using a bias voltage.

[0046] The emission of secondary electrons is suppressed by increasing the bias voltage between the inner and outer conductors of the coupler.

[0047] The connection between the coupler and the feeder is a direct connection.

[0048] The cavity vacuum and the external atmospheric environment are isolated by a coupler.

[0049] This direct connection relationship brings about the problem that the bias voltage of the coupler will be introduced into the core of the power source feed tube.

[0050] Generally speaking, the output of the power source is in the form of a coaxial interface, which is implemented using a coaxial feed tube (a waveguide method can also be used to achieve power transmission).

[0051] Ordinary coaxial feed tubes use a combination of internal feeding and external feeding to achieve the transmission of RF signals with corresponding impedance.

[0052] The size of the feed tube is related to the power of the transmitted RF signal.

[0053] We designed a high-frequency feed isolation method to realize the function of power coupling feed with bias voltage isolation.

[0054] The electrical connection between the power source and the cavity is achieved by using a coaxial feed-in method with an external high voltage bias circuit;

[0055] The DC isolation between the power source side and the accelerating cavity side is realized by using a double inner-feed sleeve wrapped with a high-isolation insulating material; a typical high-insulation material may be polyimide;

[0056] Design the length and thickness of the insulation material according to the voltage and insulation distance requirements;

[0057] A tight winding method is selected to achieve a tight connection between the insulating material and the inner feed one and the inner feed two, and to achieve DC isolation.

[0058] For the terminal between the inner feed one and the inner feed two, a material suitable for high frequency electric field and with low loss is designed to fix the terminal between the inner feed one and the inner feed two;

[0059] Thereby, a reliable microwave connection and a reliable high-voltage isolation structure are achieved between the accelerator cavity and the power source.

[0060] A particle accelerator feed isolation device, comprising:

[0061] Feeder;

[0062] Characterized in that the feed pipe comprises:

[0063] An external feed group, including an external feed line;

[0064] The internal feed group includes two sections of internal feed lines connected to each other, namely, internal feed one and internal feed two connected to the internal feed one;

[0065] An isolation layer is provided between two sections of inner feeder lines butted against each other;

[0066] The stop structure is arranged at the joint of two sections of inner feeder lines that are butted against each other.

[0067] The present invention realizes DC isolation of the feeding tube inner core on the power source side and the accelerating cavity side by designing an isolation layer between the inner feed one and the inner feed two connected to the inner feed one, thereby avoiding the problem that the bias voltage of the coupler will be introduced into the inner core of the power source feeding tube.

[0068] The second internal feedback is connected to a high voltage bias circuit.

[0069] The isolation layer is made of a polyimide film.

[0070] Feeder support flanges are provided at the ends of the inner feed 1 and the inner feed 2.

[0071] Typical example: For example, a high-frequency feed-in isolation device with a length of 395.5 mm and an interface size of 3-1 / 8” standard feed-in line specification used in a synchrocyclotron power feed-in.

[0072] In this synchrocyclotron application, a high frequency feed isolator is used to block the 3000V DC high voltage bias at the feed end.

[0073] A particle accelerator feed isolation method, comprising:

[0074] The electrical connection between the power source and the cavity is achieved by using a coaxial feed-in method with an external high voltage bias circuit;

[0075] The DC isolation between the power source side and the accelerating cavity side is realized by using a double inner-feed sleeve wrapped with a high-isolation insulating material; a typical high-insulation material may be polyimide;

[0076] Design the length and thickness of the insulation material according to the voltage and insulation distance requirements;

[0077] A tight winding method is selected to achieve a tight connection between the insulating material and the inner feed one and the inner feed two, and to achieve DC isolation.

[0078] For the terminal between the inner feed one and the inner feed two, a material suitable for high frequency electric field and with low loss is designed to fix the terminal between the inner feed one and the inner feed two;

[0079] Thereby, a reliable microwave connection and a reliable high-voltage isolation structure are achieved between the accelerator cavity and the power source.

[0080] The preferred embodiments of the present invention are described in detail above in conjunction with the accompanying drawings. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, various equivalent transformations can be made to the technical scheme of the present invention, and these equivalent transformations all belong to the protection scope of the present invention.

Claims

1. A particle accelerator feed isolation device, comprising: Feeder; Characterized in that the feed pipe comprises: An external feed group, including an external feed line; The internal feed group includes two sections of internal feed lines connected to each other, namely, internal feed one and internal feed two connected to the internal feed one; An isolation layer is provided between two sections of inner feeder lines butted against each other; the isolation layer is made of a polyimide film; The stop structure is arranged at the joint of two sections of inner feeder lines that are butted against each other.

2. A particle accelerator feed isolation device according to claim 1, characterized in that: The second internal feedback is connected to a high voltage bias circuit.

3. A particle accelerator feed isolation device according to claim 1, characterized in that: Feeder support flanges are provided at the ends of the inner feed 1 and the inner feed 2.

4. A particle accelerator feed isolation method, characterized in that: include: The electrical connection between the power source and the cavity is achieved by using a coaxial feed-in method with an external high voltage bias circuit; The DC isolation between the power source side and the accelerating cavity side is achieved by using a double inner-feed sleeve wrapped with high-isolation insulating material; Design the length and thickness of the insulating material according to the voltage and insulation distance requirements.

5. A particle accelerator feed isolation method according to claim 4, characterized in that: Also includes: A tight winding method is selected to achieve a tight connection between the insulating material and the inner feed one and the inner feed two, and to achieve DC isolation.

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