CN-121995120-A - Multi-parameter high-precision cold state test equipment for radio-frequency quadrupole accelerator

CN121995120ACN 121995120 ACN121995120 ACN 121995120ACN-121995120-A

Abstract

The invention discloses multi-parameter high-precision cold state testing equipment for a radio-frequency quadrupole accelerator, and relates to the technical field of particle accelerator testing. The leveling system is provided with a plurality of test fixtures and lifting mechanisms which can adjust the distance along the axial direction and are used for fixing and automatically leveling the RFQ cavity. The two measuring platforms are respectively arranged at two ends of the leveling system, and a rope traction mechanism with a perturbation block is arranged on the two measuring platforms. The control system integrates units such as a measurement control industrial personal computer, a network analyzer and the like, synchronously controls the cavity to automatically level, the perturbation block to move and the sweep frequency to test, and automatically collects and calculates a plurality of parameters such as resonance frequency, quality factor, field distribution, phase and mode spectrum and the like in one clamping. The invention combines leveling, automatic measurement and integrated control, and improves the efficiency, precision and repeatability of RFQ cavity cold state test compared with the problems of complicated operation, low precision and poor universality of the traditional test.

Inventors

GU LONG
ZHOU WENMING
ZHANG LU
ZHANG SHIXU
WANG GUAN
Su Xingkang

Assignees

兰州大学
福建睿斯科医疗技术有限公司

Dates

Publication Date: 20260508
Application Date: 20260409

Claims (10)

1. A multi-parameter high-precision cold state test device for a radio frequency quadrupole accelerator, comprising: the leveling system is used for assembling the RFQ cavity to be tested and comprises a supporting platform, a plurality of test clamps and a plurality of lifting mechanisms, wherein the test clamps are used for fixing and positioning the RFQ cavity to be tested, the test clamps are slidably assembled on the supporting platform through the linear guide rail module and can be axially adjusted along the cavity to adapt to the RFQ cavities with different lengths, and the lifting mechanisms are assembled at the bottom of the supporting platform and are used for adjusting the height of the cavity so as to keep the axis of the cavity in a horizontal state; The two measuring platforms are respectively arranged at two ends of the leveling system, each measuring platform comprises a field probe positioning mechanism, a rope is hung on the field probe positioning mechanism, the rope penetrates through the RFQ cavity to be measured and is hung between the two measuring platforms, and a perturbation block is arranged on the rope and used for moving in the cavity to collect electromagnetic field distribution information; The control system is respectively and electrically connected with the lifting mechanism of the leveling system and the field probe positioning mechanism of the measuring platform, and is used for controlling the lifting mechanism to automatically level the cavity, controlling the field probe positioning mechanism to drive the rope to drive the perturbation block to axially move along the cavity, synchronously controlling the radio frequency measuring unit to carry out sweep test and collecting radio frequency response data in the moving process of the perturbation block, and calculating and outputting radio frequency parameters of the RFQ cavity to be measured.
2. The multi-parameter high-precision cold state testing device of the radio-frequency quadrupole accelerator according to claim 1 is characterized in that the measuring platform further comprises a platform base, a horizontal adjusting support plate, a three-dimensional adjusting stop block and a three-dimensional fine tuning platform, wherein the platform base, the horizontal adjusting support plate, the three-dimensional adjusting stop block and the three-dimensional fine tuning platform are assembled and connected sequentially from bottom to top; the horizontal adjusting support plate is detachably arranged on the platform base through a screw rod and a nut, and the height of the horizontal adjusting support plate is adjusted through screwing the nut; the field probe positioning mechanism is assembled on the three-dimensional fine adjustment platform.
3. The multi-parameter high-precision cold state testing device of the radio-frequency quadrupole accelerator according to claim 2, wherein the three-dimensional adjusting stop block comprises a bottom plate and first limiting blocks arranged on the periphery of the bottom plate, the first limiting blocks are connected with first threaded ejector rods in a threaded mode, the first threaded ejector rods are abutted to the side edges of the bottom plate and used for adjusting the left-right and front-back positions of the bottom plate, the three-dimensional adjusting stop block further comprises second limiting blocks arranged on two sides of the bottom plate, the second limiting blocks are connected with second threaded ejector rods in a threaded mode, and the bottoms of the second threaded ejector rods are rotatably connected to the top face of the bottom plate and used for adjusting the height of the bottom plate.
4. The multi-parameter high-precision cold state testing device of the radio-frequency quadrupole accelerator according to claim 2, wherein the three-dimensional fine tuning platform comprises a base, a first sliding block, a second sliding block and a third sliding block which are sequentially connected through sliding blocks, wherein the first sliding block is assembled on the base in a sliding way, the second sliding block is assembled on the first sliding block in a sliding way, and the third sliding block is assembled on the second sliding block in a sliding way; the second sliding block is of an L-shaped structure, one surface of the second sliding block is assembled with the first sliding block in a left-right sliding mode, and the other surface of the second sliding block is assembled with the third sliding block in a vertical sliding mode; Be provided with first regulation pole on the base, first slider is connected to first one end of adjusting the pole to promote first slider and reciprocate on the base, is provided with the second on the first slider and adjusts the pole, and the second slider is connected to the one end of second regulation pole to promote the second slider and reciprocate on first slider, is provided with the third on the second slider and adjusts the pole, and the third slider is connected to the one end of third regulation pole, so as to promote the third slider and reciprocate on the second slider.
5. The multi-parameter high-precision cold state testing device of the radio-frequency quadrupole accelerator of claim 1, wherein the field probe positioning mechanism comprises four pulleys and tensioning wheels, two of the pulleys are arranged on one measuring platform, and the other two are arranged on the other measuring platform, so that ropes are supported by the two pulleys at two ends of an RFQ cavity respectively; the rope passes through the RFQ cavity and is hung on pulleys arranged at two ends to form a closed loop structure, and the tensioning wheel is abutted with the rope and used for adjusting the tightness of the rope.
6. The multi-parameter high-precision cold state testing device of the radio-frequency quadrupole accelerator of claim 5, wherein the field probe positioning mechanism further comprises a traction wheel, the traction wheel is connected with a rope, and a servo motor is further connected with the traction wheel and used for driving the traction wheel to operate so that the rope drives the perturbation block to axially move in the RFQ cavity.
7. The multi-parameter high-precision cold state testing device of the radio-frequency quadrupole accelerator of claim 1, wherein each lifting mechanism comprises a servo motor, a speed reducer and a screw lifting assembly; the screw lifting assembly comprises a screw and a screw nut, the servo motor drives the screw to rotate through a speed reducer, and the screw nut is connected with a supporting table top for supporting the end part of the cavity; The servo motor is internally provided with an encoder and is used for feeding back the height position of the supporting table top in real time, and the control system is used for controlling the servo motors at the two ends to act in a closed loop mode according to the height difference at the two ends of the cavity until the height difference at the two ends is within a preset tolerance range, so that the axis of the cavity reaches a horizontal state.
8. The multi-parameter high-precision cold state testing device of the radio-frequency quadrupole accelerator of claim 1, wherein the testing fixture comprises a supporting seat and a clamping mechanism; The support seat comprises a T-shaped seat which is assembled at the top of the support seat in a sliding manner and is used for supporting a cylindrical shell or a flange part of the cavity; The clamping mechanism is used for fixing the cavity on the supporting seat, and the supporting seat is connected with the leveling system through the linear guide rail and is used for sliding along the axial direction of the cavity so as to adjust the distance between the supporting seats.
9. The multi-parameter high-precision cold state testing device of the radio-frequency quadrupole accelerator of claim 8, wherein the supporting seat is provided with a fine adjustment mechanism for finely adjusting the height and lateral position of the cavity; the fine adjustment mechanism comprises fixing blocks arranged on two sides of the supporting seat and bolts which are arranged on the fixing blocks in a threaded manner, one ends of the bolts are abutted against the T-shaped seat and used for pushing the T-shaped seat to move laterally on the supporting seat; the fine adjustment mechanism further comprises an adjustor which is rotatably arranged on the T-shaped seat and connected with the clamping mechanism and used for adjusting the height of the clamping mechanism.
10. The multi-parameter high-precision cold state test equipment of the radio-frequency quadrupole accelerator according to claim 1, wherein the control system comprises a control unit cabinet, and a measurement control industrial personal computer, a network data switch, a power supply system and a network analyzer which are arranged in the control unit cabinet; The measurement control industrial personal computer is in communication connection with the network analyzer through the network data switch, and the power supply system is used for supplying power to all the power utilization components; the measuring control industrial personal computer controls servo motors of the lifting mechanism and the field probe positioning mechanism through a servo driving module, and controls the network analyzer to execute sweep frequency test through the network data exchanger; When the perturbation block moves to each preset position, the measurement control industrial personal computer triggers the network analyzer to collect transmission characteristic data at the position, and the position information of the perturbation block is stored in association with radio frequency response data.

Description

Multi-parameter high-precision cold state test equipment for radio-frequency quadrupole accelerator Technical Field The invention relates to the technical field of particle accelerator testing, in particular to multi-parameter high-precision cold state testing equipment for a radio-frequency quadrupole accelerator. Background A radio frequency quadrupole accelerator (Radio Frequency Quadrupole, abbreviated as RFQ) is a commonly used linear accelerator structure that focuses and accelerates the ion beam at low energy segments through quadrupole electrodes. Electromagnetic parameters of the RFQ cavity, such as resonant frequency, field intensity distribution, phase position and the like, are critical to acceleration performance. Before RFQ is formally put into high power operation, it is usually necessary to perform a cold state test, i.e. to measure and verify the resonance characteristics and field distribution of the cavity under the condition of no beam and low power radio frequency. The cold state test can effectively reveal the problems of resonance frequency drift, nonuniform electric field distribution in an acceleration cavity, coupling of unexpected modes and the like caused by manufacturing tolerances and assembly deviations. The influence of the factors on the uniformity and stability of the acceleration field can be compensated by tuning and correcting the test result, so that the electromagnetic performance of the cavity in the actual working state is ensured to meet the design requirement. Existing RFQ cold test methods often require multiple independent measurement procedures and manual adjustments. In particular, the resonant frequency and quality factor of the cavity is typically measured using a network analyzer, the axial field strength distribution is measured using a "bead pull" method or a moving probe, and the resonant modes are identified using different coupling ports or probes. However, each measurement usually requires a separate device and step, which is complicated to operate, and multiple disassembly and assembly of the cavity between different measurement items are required, which easily introduces accumulated errors and affects the accuracy of the test result. Furthermore, in order to obtain reliable data, the cavity needs to be precisely aligned and leveled before testing. In the prior art, manual leveling is usually carried out by adopting a mode of adjusting gaskets or bolts at two ends of a cavity, and the method has limited precision and poor repeatability. The same test condition is difficult to recover after each disassembly and assembly, so that the consistency of test results of different batches is difficult to ensure, and the subsequent tuning and correction work is difficult. Meanwhile, the adaptation of RFQ cavities of different specifications on a test platform is also problematic. The RFQ cavity has various structural forms, such as four-bar type or four-plate type, and has different lengths. The existing test platform often needs to customize a special supporting clamp for each cavity, lacks generality, increases test cost and period, and limits the application range of the test platform. Disclosure of Invention In order to overcome the defects in the prior art, the invention provides multi-parameter high-precision cold state testing equipment for a radio-frequency quadrupole accelerator, which solves the problems in the background art. The invention provides a technical scheme that a multi-parameter high-precision cold state test device of a radio-frequency quadrupole accelerator comprises the following components: the leveling system is used for assembling the RFQ cavity to be tested and comprises a supporting platform, a plurality of test clamps and a plurality of lifting mechanisms, wherein the test clamps are used for fixing and positioning the RFQ cavity to be tested, the test clamps are slidably assembled on the supporting platform through the linear guide rail module and can be axially adjusted along the cavity to adapt to the RFQ cavities with different lengths, and the lifting mechanisms are assembled at the bottom of the supporting platform and are used for adjusting the height of the cavity so as to keep the axis of the cavity in a horizontal state; The two measuring platforms are respectively arranged at two ends of the leveling system, each measuring platform comprises a field probe positioning mechanism, a rope is hung on the field probe positioning mechanism, the rope penetrates through the RFQ cavity to be measured and is hung between the two measuring platforms, and a perturbation block is arranged on the rope and used for moving in the cavity to collect electromagnetic field distribution information; The control system is respectively and electrically connected with the lifting mechanism of the leveling system and the field probe positioning mechanism of the measuring platform, and is used for controlling the lifting mechanism to automaticall