A high-voltage insulation detection device for superconducting cyclotron electrostatic deflection plates

Abstract

This invention discloses a high-voltage insulation detection device for an electrostatic deflection plate in a superconducting cyclotron accelerator, relating to particle accelerator engineering and high-voltage insulation testing technology. The device includes: a C-type diode, a vacuum chamber, an electrostatic deflection plate, a high-voltage vacuum feedthrough, a high-voltage insulation platform, and a collaborative monitoring and data acquisition system. The collaborative monitoring and data acquisition system includes leakage current, vacuum level, magnetic field, and high-voltage status acquisition units, an optical observation unit, and a control and processing unit. The control and processing unit performs synchronous sampling of multi-source signals using a unified time reference, stores image frames in association according to timestamps, and generates discharge event markers based on leakage current mutations or discharge characteristics. This invention reproduces the combined strong magnetic field and high vacuum conditions before assembly, making the test environment closer to the actual operating state; through synchronous acquisition of multi-source signals and event-triggered association storage, it achieves full-dimensional traceability recording of the discharge process; improving the authenticity and reliability of test results.

Description

Technical Field

[0001] This invention relates to the fields of particle accelerator engineering and high-voltage insulation testing technology, and in particular to a high-voltage insulation testing device for electrostatic deflection plates in superconducting cyclotron accelerators. Background Technology

[0002] As a core piece of equipment in fields such as proton therapy, isotope production, and nuclear physics research, the operational stability and reliability of superconducting cyclotrons are of paramount importance. The electrostatic deflector plate is a key component of the superconducting cyclotron's extraction system. By applying a high voltage of tens of kilovolts to create a strong electrostatic field, it deflects and extracts the charged particle beam accelerated to its rated energy from the main magnetic field region. In actual operation, the electrostatic deflector plate operates under the extreme combined conditions of strong magnetic field, high vacuum, and high voltage. Its insulation reliability directly affects the efficiency and stability of beam extraction, and even the overall operational safety of the accelerator.

[0003] In traditional engineering practice, the high-voltage insulation performance verification of electrostatic deflection plates is often carried out using the following methods:

[0004] Firstly, it relies on on-site commissioning after the entire superconducting cyclotron accelerator is assembled. This involves conducting withstand voltage tests and aging treatments on the electrostatic deflection plates under actual operating conditions after the superconducting cyclotron accelerator is fully assembled. The drawback of this method is that if an insulation failure event such as arcing, flashover, or breakdown occurs during commissioning, troubleshooting requires shutdown, vacuum breaking, and disassembly of the chamber, resulting in a long rectification period, high costs, and severely impacting equipment delivery schedules and operational availability.

[0005] Secondly, offline testing is conducted using an independent vacuum testing device. For example, Chinese utility model patent announcement number CN217879498U discloses a high-voltage testing device for an electrostatic deflection plate. This device places the electrostatic deflection plate inside a vacuum chamber, evacuates it to a high vacuum using an external vacuum pump, and applies a detection voltage via a high-voltage power supply unit to evaluate the deflection plate's withstand voltage performance in a vacuum environment. However, this type of device can only reproduce high vacuum conditions and cannot simulate the strong magnetic field background of the superconducting cyclotron accelerator's extraction region. This results in significant differences between the test conditions and actual operating conditions, making it difficult to accurately reflect the insulation behavior and discharge characteristics of the deflection plate under a magnetic field-vacuum coupled field.

[0006] Thirdly, status monitoring and fault prediction are performed during operation. For example, Chinese patent application publication number CN119403029A discloses a method for controlling the impact of arcing in the extraction system. This method involves real-time acquisition of parameters such as leakage current and vacuum level of the electrostatic deflection plate during proton therapy, and prediction of feed voltage fluctuations based on an LSTM model, thereby preemptively shutting off the beam to avoid the impact of arcing on treatment. This approach focuses on real-time control and fault avoidance during operation, rather than verifying the insulation performance during the manufacturing or assembly phase of the deflection plate; its data acquisition and processing logic serves the control objective of "pausing treatment" and does not involve simultaneous recording of multiple parameters or traceable storage of discharge events.

[0007] In summary, the existing technology has the following shortcomings:

[0008] 1. Offline testing devices can only provide vacuum conditions and cannot simulate strong magnetic field backgrounds, resulting in a disconnect between the test conditions and actual working conditions;

[0009] 2. Relying on a single electrical parameter (such as leakage current) for judgment makes it difficult to fully capture the multi-dimensional characteristics of discharge transients;

[0010] 3. The lack of a multi-source signal synchronous acquisition and event triggering recording mechanism makes it difficult to reproduce and analyze the causes and consequences after a discharge occurs;

[0011] 4. The testing process lacks standardized and automated process management, resulting in poor comparability of test results from different batches.

[0012] Therefore, a detection device is needed that can perform high-voltage tests under strong magnetic field conditions and has the ability to simultaneously acquire multi-source parameters and record discharge events, in order to support the quantitative evaluation and acceptance of electrostatic deflection plate process schemes. Summary of the Invention

[0013] In order to overcome the above-mentioned defects of the prior art, the present invention provides a high-voltage insulation detection device for electrostatic deflection plates of superconducting cyclotron accelerators, so as to solve the problems existing in the background art.

[0014] This invention provides the following technical solution: a high-voltage insulation detection device for an electrostatic deflection plate of a superconducting cyclotron accelerator, comprising:

[0015] A C-type dipole iron, with a test air gap formed between its upper and lower magnetic poles to simulate the background magnetic field of the extraction region of a superconducting cyclotron accelerator;

[0016] A vacuum chamber is arranged within the test air gap;

[0017] A vacuum system, connected to the vacuum chamber, is used to pump the vacuum level inside the vacuum chamber to a predetermined value and maintain it stably.

[0018] An electrostatic deflection plate is installed inside the vacuum chamber;

[0019] A high-voltage vacuum power supply passes through the wall of the vacuum chamber and is electrically connected to the high-voltage electrode of the electrostatic deflection plate, used to introduce high voltage between the vacuum and the atmosphere;

[0020] A high-voltage insulation platform is used to support the vacuum box and electrically isolate the high-voltage components from ground potential, providing the necessary electrical clearance and equivalent creepage path;

[0021] Collaborative monitoring and data acquisition system, including:

[0022] Multiple acquisition units, including at least a leakage current acquisition unit, a vacuum degree acquisition unit, a magnetic field acquisition unit, a high voltage status acquisition unit, and an optical observation unit;

[0023] The control and processing unit is connected to the plurality of acquisition units and the optical observation unit, respectively;

[0024] The control processing unit performs synchronous sampling of leakage current, vacuum degree, magnetic field strength and high voltage state quantity under a unified time reference, and stores the image frames collected by the optical observation unit in association with the synchronous sampling data according to the timestamp; the control processing unit has a built-in event criterion module, which is used to monitor multi-source signals in real time based on preset discharge criteria, and generate discharge event markers when the criteria are met, so as to form a corresponding record of discharge events and multi-source parameters.

[0025] Preferably, the pole face dimensions of the C-type diode are matched with the outer dimensions of the vacuum chamber, and the vacuum chamber is set in the central region between the upper and lower pole faces of the C-type diode, so that the electrostatic deflection plate is subjected to high voltage testing in an approximately uniform magnetic field of 0.9 to 1.2T.

[0026] Preferably, the high-voltage insulation platform includes a metal support base located below and a G10 epoxy fiberglass board disposed on the metal support base, wherein the thickness of the G10 epoxy fiberglass board is not less than 30mm.

[0027] Preferably, the optical observation unit is a CCD camera, which observes the surface discharge morphology of the electrostatic deflection plate through a transparent observation window set on the side wall of the vacuum chamber; the transparent observation window is made of quartz glass or optical glass and is fixed to the vacuum chamber by a metal sealing method.

[0028] Preferably, the discharge criterion of the event criterion includes at least one or a combination of the following: leakage current exceeding a preset threshold, leakage current change rate exceeding a preset threshold, and optically observed discharge characteristics.

[0029] Preferably, the collaborative monitoring and data acquisition system further includes a host computer, which manages the test process in a streamlined manner based on a preset test formula. The test formula includes at least magnetic field settings, step voltage ramp parameters, holding time, and event handling rules. When the control processing unit outputs a discharge event marker, the host computer records the corresponding data before and after the event and executes the corresponding handling strategy.

[0030] Preferably, the leakage current acquisition unit includes a microammeter or current sensor connected in series with the high-voltage circuit of the electrostatic deflection plate, with a range of no more than 200μA.

[0031] Preferably, the high-voltage vacuum power supply is a metal-ceramic sealed structure, with its vacuum side end connected to the high-voltage electrode of the electrostatic deflection plate via a detachable connector, and the atmospheric side provided with a shielded connector for connecting to the output cable of an external high-voltage system.

[0032] Preferably, the control processing unit is a PLC controller, and the host computer receives multi-source monitoring signals with timestamps uploaded by the PLC controller; when a discharge event is detected, the PLC controller outputs an event marker, and the host computer saves the electrical parameter records within a preset time window before and after the event and the corresponding image frames of the same time period, so as to realize the traceable recording of the discharge process.

[0033] Preferably, it further includes a position adjustment mechanism, the position adjustment mechanism comprising:

[0034] The drive unit is located outside the vacuum chamber;

[0035] The adjusting rod has one end connected to the drive unit and the other end extending through the vacuum chamber wall into the vacuum chamber.

[0036] A vacuum bellows is fitted over the outside of the adjusting rod, with one end sealed to the wall of the vacuum chamber and the other end sealed to the adjusting rod.

[0037] An insulating transmission component is disposed between the end of the adjusting rod that extends into the vacuum chamber and the electrostatic deflection plate, for transmitting driving force and achieving electrical isolation;

[0038] The drive unit drives the electrostatic deflection plate to move within the vacuum chamber via the adjusting rod and the insulating transmission component to adjust its position.

[0039] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0040] 1. This invention integrates a C-type diode and a vacuum chamber into the same testing device, allowing the electrostatic deflection plate to undergo high-voltage testing within the test air gap between the upper and lower magnetic poles of the C-type diode. This enables the simultaneous reproduction of the combined strong magnetic field and high vacuum conditions of the superconducting cyclotron's extraction zone during the testing phase. Compared to traditional methods that can only be tested in a vacuum environment, this testing environment is closer to the actual operating conditions of the deflection plate, and can truly reflect the influence of the strong magnetic field on the electric field distribution, secondary electron emission, and discharge characteristics, thereby improving the effectiveness and reliability of insulation performance evaluation.

[0041] 2. This invention integrates at least five types of acquisition units—leakage current, vacuum level, magnetic field strength, high voltage status, and optical observation—through a collaborative monitoring and data acquisition system. These signals are synchronously sampled using a unified time reference. Image frames acquired by the CCD camera are stored in association with electrical parameter data according to timestamps. Compared to traditional methods that rely solely on a single optical signal to detect discharge or only acquire electrical parameters for predictive control, this invention constructs a five-dimensional integrated data recording system encompassing voltage, current, vacuum, magnetic field, and images, providing complete data support for the mechanism analysis of discharge behavior and fault reproduction.

[0042] 3. This invention is equipped with an event criterion module, which has multiple criteria such as leakage current exceeding the threshold, leakage current change rate exceeding the threshold, or optical observation of discharge characteristics. When the criteria are met, a discharge event marker is automatically generated, triggering data encryption sampling and image capture. The multi-source data within a preset time window before and after the event is associated and stored. This mechanism effectively solves the problem of the difficulty in stably capturing transient discharge events, so that each discharge can be accurately located and completely recorded, thereby improving the repeatability and consistency of criteria in aging and withstand voltage evaluation.

[0043] 4. The host computer set in this invention supports preset test formulas, including at least magnetic field setting values, step voltage increase parameters, holding time and event handling rules. It can automatically execute processes such as interlock checks, voltage increase and holding cycles, discharge event response and data archiving. Compared with the traditional testing method that relies on manual operation and experience judgment, formula-based management ensures the consistency of test conditions between different batches and different parts. It not only reduces the impact of human factors on test results, but also improves the objectivity and efficiency of process verification and factory acceptance.

[0044] 5. This invention, through the collaborative work of the control processing unit and the host computer, adds a unified time stamp to multi-source monitoring signals, and automatically saves the electrical parameter data within a preset time window before and after the discharge event and the corresponding image frames in the same time period, forming a traceable record file of the discharge process. The traceability system provides a detailed data foundation for subsequent fault analysis, process optimization and quality backtracking, effectively solving the problem of broken evidence chains caused by traditional manual recording or asynchronous recording by multiple devices. Attached Figure Description

[0045] Figure 1 This is a three-dimensional schematic diagram of the detection device of the present invention.

[0046] Figure 2 This is a schematic diagram of the electrostatic deflection plate installation according to the present invention.

[0047] Figure 3 This is a side view schematic diagram of the detection device of the present invention.

[0048] Figure 4 This is a schematic diagram of the adjustment mechanism of the present invention.

[0049] Figure 5 This is a block diagram of the collaborative monitoring and data acquisition system of the present invention.

[0050] The attached diagram is labeled as follows: 1. Type C polaritron; 2. Vacuum chamber; 3. Pumping system; 4. Electrostatic deflection plate; 5. High-voltage vacuum power supply; 6. High-voltage insulating platform; 61. Metal bearing base; 62. G10 epoxy fiberglass board; 7. Collaborative monitoring and data acquisition system; 71. Leakage current acquisition unit; 72. Vacuum degree acquisition unit; 73. Magnetic field acquisition unit; 74. High-voltage status acquisition unit; 75. Optical observation unit; 76. Control and processing unit; 77. Host computer; 78. Transparent observation window; 8. Adjustment mechanism; 81. Servo motor; 82. Reducer; 83. Electric cylinder; 84. Adjusting rod; 85. Vacuum bellows; 86. PEEK connector; 87. Insulating shaft. Detailed Implementation

[0051] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby providing a clearer and more explicit definition of the scope of protection of the present invention.

[0052] This invention provides a high-voltage insulation detection device for electrostatic deflection plates in superconducting cyclotron accelerators, such as... Figure 1-4 As shown, it includes: a C-type diode 1, a vacuum box 2, a pumping system 3, an electrostatic deflection plate 4, a high-voltage vacuum power supply 5, a high-voltage insulation platform 6, and a collaborative monitoring and data acquisition system 7.

[0053] The C-type dipole 1 consists of upper and lower magnetic poles and a yoke connecting them, forming a test air gap between the upper and lower magnetic poles to simulate the background magnetic field in the extraction region of a superconducting cyclotron accelerator. The pole face dimensions of the C-type dipole 1 match the external dimensions of the vacuum chamber 2 to ensure the uniformity of the magnetic field distribution. The excitation coil of the C-type dipole 1 is electrically connected to an external excitation power supply. By adjusting the excitation current, the magnetic field strength within the test air gap can be controlled to achieve the preset test requirements.

[0054] Vacuum chamber 2 is positioned within the test air gap of the C-type dipole 1, specifically in the central region between the upper and lower magnetic poles, to ensure that the electrostatic deflection plate 4 is in a uniform magnetic field. Vacuum chamber 2 is welded from stainless steel, possessing sufficient mechanical strength and vacuum sealing performance. Multiple interfaces are provided on the side walls and bottom of vacuum chamber 2, including an air extraction port, a feedthrough mounting hole, an observation window mounting hole, and a measurement interface.

[0055] The evacuation system 3 is connected to the evacuation port of the vacuum chamber 2 via a bellows, and is used to evacuate the vacuum level inside the vacuum chamber 2 to a predetermined value and maintain it stably. The evacuation system 3 includes a vacuum pump, vacuum valves, and a vacuum gauge, and can achieve an ultimate vacuum level inside the vacuum chamber 2 better than 3 × 10⁻⁶. -5 Pa, and remains dynamically stable during the test.

[0056] The electrostatic deflection plate 4 is installed inside the vacuum chamber 2. Its shape, size and installation method are the same as or scaled down to the actual deflection plate used in the take-off area of ​​the superconducting cyclotron.

[0057] The high-voltage vacuum feeder 5 passes through the wall of the vacuum chamber 2 and is electrically connected to the high-voltage electrode of the electrostatic deflection plate 4, used to introduce high voltage between the vacuum environment and the atmospheric environment. In this embodiment, the high-voltage vacuum feeder 5 adopts a metal-ceramic sealing structure, giving it excellent vacuum sealing and high-voltage insulation performance. Its vacuum side end is connected to the high-voltage electrode of the electrostatic deflection plate 4 through a detachable connector, facilitating disassembly and maintenance; the atmospheric side is equipped with a shielded connector for connecting to the output cable of an external high-voltage system, reducing electromagnetic interference.

[0058] A high-voltage insulation platform 6 supports the vacuum chamber 2 and electrically isolates the high-voltage components from ground potential. In this embodiment, the high-voltage insulation platform 6 includes a lower metal support base 61 and a G10 epoxy fiberglass board 62 mounted on the metal support base 61. The G10 epoxy fiberglass board 62 has a thickness of not less than 30 mm. The metal support base 61 is fixed to the laboratory foundation with anchor bolts, and the G10 epoxy fiberglass board 62 is fixedly connected to the metal support base 61 with insulating bolts. The vacuum chamber 2 is entirely mounted on the G10 epoxy fiberglass board 62, ensuring sufficient insulation strength between the vacuum chamber 2 and its internal high-voltage components and ground potential.

[0059] The collaborative monitoring and data acquisition system 7 includes: multiple acquisition units, an optical observation unit 75, a control and processing unit 76, and a host computer 77.

[0060] Multiple acquisition units include at least:

[0061] Leakage current acquisition unit 71: includes a microammeter or high-precision current sensor connected in series with the high-voltage circuit of the electrostatic deflection plate 4, used to measure the leakage current change of the electrostatic deflection plate 4 in real time during the withstand voltage and aging process. In this embodiment, the leakage current acquisition unit 71 is connected in series with the ground terminal of the high-voltage circuit, and its output signal is connected to the control processing unit 76.

[0062] Vacuum acquisition unit 72: Connected to the vacuum gauge installed on the vacuum chamber 2, it is used to acquire the pressure value inside the vacuum chamber 2 in real time. The vacuum gauge can be an ionization vacuum gauge or a compound vacuum gauge, and its analog output or digital communication interface is connected to the control processing unit 76.

[0063] Magnetic field acquisition unit 73: Connected to a magnetic field sensor, it is used to read the magnetic flux density in the test air gap of the C-type dipole iron 1 in real time. The magnetic field sensor can be a Hall probe or a nuclear magnetic resonance probe, which is arranged outside the vacuum chamber 2 near the center of the test air gap, and its output signal is connected to the control processing unit 76.

[0064] High voltage status acquisition unit 74: connected to the voltage feedback port of the external high voltage system, or acquired through a high voltage divider and current sampling resistor, used to monitor the high voltage value applied to the electrostatic deflection plate 4 and the output status of the high voltage power supply in real time, and its output signal is connected to the control processing unit 76.

[0065] The optical observation unit 75 is a CCD camera that observes the surface discharge, flashover, or arc morphology of the electrostatic deflection plate 4 through a transparent observation window 78 located on the side wall of the vacuum chamber 2. The transparent observation window 78 is made of quartz glass or optical glass, possessing good light transmittance and insulation properties, and is fixed to the vacuum chamber 2 using a metal ring seal or welding method to ensure reliable vacuum sealing. The CCD camera is positioned outside the vacuum chamber 2 at an appropriate distance from the observation window and is equipped with a zoom lens to adapt to different field-of-view requirements. The image output of the CCD camera is directly connected to the host computer 77 monitoring terminal via communication interfaces such as GigE, CameraLink, or USB.

[0066] The control processing unit 76 is used for synchronous acquisition of multi-source signals, judgment of event criteria, issuance of control commands, and data interaction with the host computer 77.

[0067] In this embodiment, the control processing unit 76 is implemented using a PLC controller, which includes a CPU module, an analog input module, a digital input / output module, and a communication module. The control processing unit 76 is connected to the leakage current acquisition unit 71, the vacuum degree acquisition unit 72, the magnetic field acquisition unit 73, and the high voltage status acquisition unit 74, respectively, and performs periodic synchronous sampling of each analog signal, and adds a unified timestamp based on the system clock to each sampling point.

[0068] The control processing unit 76 has a built-in event criterion module, which is embedded in the PLC's CPU execution program as a software function block. The event criterion module includes at least one or a combination of the following: leakage current exceeds a preset threshold, leakage current change rate exceeds a preset threshold. When the control processing unit 76 detects that the criteria are met, it immediately generates a discharge event flag and outputs an event trigger signal to trigger data encryption sampling, image capture, or data storage.

[0069] Meanwhile, the control processing unit 76 controls the start and stop of the high voltage power supply, voltage setting, and excitation current of the magnet power supply through the digital output module to realize the automated control of the test process; it communicates with the host computer 77 via Ethernet through the communication module, uploads multi-source data with timestamps, and receives test formula parameters issued by the host computer 77.

[0070] It should be noted that the control processing unit 76 is not limited to a PLC controller. In other embodiments, it can also be implemented using hardware with data processing and control functions such as an industrial control computer, embedded system, or FPGA, as long as it can complete the synchronous acquisition of multi-source signals, the judgment of event criteria, and the control of equipment.

[0071] The host computer 77, a monitoring terminal, is an industrial control computer or workstation equipped with dedicated monitoring software. It communicates with the control processing unit 76 via Ethernet to read multi-source monitoring data with timestamps in real time. Simultaneously, it connects to a CCD camera via a GigE or USB interface to receive image data. The host computer 77 is responsible for human-computer interaction, experimental formula management, image processing, data storage, and report generation.

[0072] The host computer 77 includes an image processing module that can analyze the image frames acquired by the CCD camera in real time, identify discharge characteristics (such as the optical characteristics of flashover and arc), and feed the identification results back to the control processing unit 76 as supplementary input for event criteria.

[0073] In this embodiment, the host computer 77 manages the test process in a streamlined manner based on preset test recipes. The test recipe includes at least: magnetic field setting value, initial voltage for stepped voltage increase, voltage increase step, single-stage holding time, target voltage, cumulative holding time, leakage current threshold, event handling rules, and interlocking conditions. Operators can create, edit, and select different test recipes through the human-machine interface of the host computer 77 software.

[0074] Before the test begins, the host computer 77 automatically performs interlock checks, including: determining whether the vacuum level has reached the set value, whether the deviation between the actual magnetic field and the set value is within the allowable range, access control safety interlocks, and whether the cooling system is ready. Only after all interlock conditions are met can the next step be performed.

[0075] During the experiment, the host computer 77, following the stepped voltage increase strategy set in the formula, sends control commands to the high-voltage power supply through the control processing unit 76, gradually increasing the high voltage applied to the electrostatic deflection plate 4. After reaching each voltage level, it maintains the voltage for a preset time. During this period, the control processing unit 76 continuously collects multi-source data and uploads it to the host computer 77 for real-time display.

[0076] When the event criterion built into the control processing unit 76 detects that the leakage current exceeds the threshold or the leakage current change rate exceeds the threshold, it immediately generates a discharge event marker and uploads the event occurrence time and event identifier to the host computer 77 via Ethernet. After receiving the event marker, the host computer 77 automatically records the event occurrence time, corresponding voltage level, and handling result, and performs voltage reduction, shutdown, or maintenance operations through the control processing unit 76 according to the event handling rules preset in the recipe.

[0077] Once the voltage reaches its maximum and the cumulative holding time meets the requirements, the host computer 77 determines that the test is qualified and automatically generates a test report; if an irreversible continuous discharge or leakage current continues to exceed the limit within the specified time, the test is deemed unqualified and terminated.

[0078] To ensure the traceability of discharge events, this embodiment employs a multi-source signal synchronous acquisition and associated storage mechanism with a unified time reference.

[0079] The control processing unit 76 synchronously samples the signals from each sensor and adds a unique timestamp to each sampling point. The sampled data includes leakage current, vacuum level, magnetic field strength, and high-voltage status. Simultaneously, the host computer 77 receives image frames acquired by the CCD camera and adds a timestamp to each frame.

[0080] When the control processing unit 76 detects a discharge event, it generates an event marker and sends the event occurrence time to the host computer 77. Upon receiving the event marker, the host computer 77 automatically extracts all electrical parameter sampling data within a preset time window from the database, matches it with image frames within that time window, and stores the associated data packet in a dedicated folder named after the test number. The stored data packet includes: event marker, timestamp sequence, electrical parameter values, image file path, and event description information.

[0081] This associated storage mechanism ensures that each discharge event can be fully reproduced, providing a detailed data foundation for subsequent fault analysis, process optimization, and quality backtracking.

[0082] Based on the above-described device, this embodiment also provides a high-voltage insulation detection method for the electrostatic deflection plate 4 of a superconducting cyclotron accelerator, comprising the following steps:

[0083] S1: Environment Setup. The electrostatic deflection plate 4 to be tested is installed in the vacuum chamber 2, and the vacuum chamber 2 is placed in the center region of the test air gap of the C-type diode 1; the pumping system 3 is started to pump the vacuum chamber 2 to the predetermined vacuum level and maintain it stable; the C-type diode 1 is energized to establish a uniform background magnetic field of 0.9 to 1.2 T in the test air gap.

[0084] S2: High Voltage Application and Testing. A high voltage is applied to the high voltage electrode of the electrostatic deflection plate 4 via the high-voltage vacuum feedthrough 5, and a withstand voltage or aging test is performed according to a preset stepped voltage ramping strategy. The stepped voltage ramping strategy includes setting the initial voltage, voltage ramping step, single-stage holding time, and target voltage.

[0085] S3: Synchronous acquisition of multi-source signals. During the experiment, the control and processing unit 76 synchronously acquires leakage current, vacuum degree, magnetic field strength, and high voltage status with a unified time reference, while the host computer 77 synchronously acquires surface discharge images of the electrostatic deflection plate 4.

[0086] S4: Event Detection and Trigger Recording. The control processing unit 76 monitors multi-source signals in real time. When the preset event criteria (leakage current exceeding the threshold, leakage current change rate exceeding the threshold) are met, a discharge event marker is automatically generated, and the event occurrence time is sent to the host computer 77. The host computer 77 associates all electrical parameter data and image frames within the preset time window before and after the event and stores them in the test database to form a traceable discharge event record.

[0087] S5: Formula-based process management. The host computer 77 automates the management of the test process based on preset test formulas, including interlock checks, stepped voltage control, event response and handling, and pass / fail determination. After the test, a test report is automatically generated.

[0088] As a further improvement, the device may also include a position adjustment mechanism 8 for adjusting the gap or orientation of the electrostatic deflection plate 4 before or during the test.

[0089] The adjustment mechanism 8 includes: a drive unit, an adjustment rod 84, a vacuum bellows 85, and an insulated transmission component.

[0090] The drive unit is located outside the vacuum chamber 2 and provides adjustment power. In this preferred embodiment, the drive unit includes a servo motor 81, a reducer 82, and an electric cylinder 83. The output shaft of the servo motor 81 is connected to the input end of the reducer 82, and the output end of the reducer 82 is connected to the drive end of the electric cylinder 83, converting rotary motion into linear motion through the electric cylinder 83. The entire drive unit is mounted on a dedicated bracket on the high-voltage insulated platform 6 to ensure isolation from ground potential.

[0091] One end of the adjusting rod 84 is connected to the drive unit, and the other end extends into the vacuum chamber 2 through the wall of the vacuum chamber 2. Specifically, one end of the adjusting rod 84 is fixedly connected to the telescopic end of the electric cylinder 83 via a connecting shaft, and the other end is connected to the electrostatic deflection plate 4 via an insulated transmission component.

[0092] The vacuum bellows 85 is sleeved outside the adjusting rod 84. One end is welded to the sealing interface on the wall of the vacuum chamber 2 or connected by a flange seal, and the other end is welded to the adjusting rod 84 or connected by a dynamic sealing structure. While ensuring a vacuum seal, the vacuum bellows 85 allows the adjusting rod 84 to move axially and swing slightly at an angle, realizing mechanical transmission under dynamic sealing conditions.

[0093] An insulated transmission component is positioned between the end of the adjusting rod 84 that extends into the vacuum chamber 2 and the electrostatic deflection plate 4, serving to transmit driving force and achieve electrical isolation. In this embodiment, the insulated transmission component includes a PEEK connector 86 and an insulated shaft 87. One end of the PEEK connector 86 is fixedly connected to the adjusting rod 84, and the other end is connected to the insulated shaft 87; the insulated shaft 87 is rotatably connected to the electrostatic deflection plate 4 via a rotating support. PEEK material possesses excellent high-voltage insulation properties and mechanical strength, capable of withstanding tens of kilovolts of high voltage without breakdown or creepage. The rotating support is fixed to the side of the electrostatic deflection plate 4 near the adjusting rod 84, and contains bearings or bushings, allowing the insulated shaft 87 to rotate relative to the rotating support, thereby achieving angle adjustment of the deflection plate.

[0094] The drive unit moves the electrostatic deflector plate 4 within the vacuum chamber 2 via the adjusting rod 84 and the insulating transmission component to adjust its position or orientation. Specifically, when the drive unit outputs linear motion, the adjusting rod 84 pushes or pulls the insulating transmission component, causing the electrostatic deflector plate 4 to translate axially; when two drive units work together, the electrostatic deflector plate 4 can rotate around the rotating support, achieving angle adjustment. The entire adjustment process can be completed without disrupting the vacuum or stopping the machine, significantly improving experimental efficiency.

[0095] In another embodiment, the drive unit can also employ a manually adjustable structure (such as a differential head with a bellows) or a precision drive element such as a piezoelectric ceramic actuator, which can also achieve the position adjustment function. The insulated transmission components can also be made of other highly insulating materials.

[0096] The installation steps for this device are as follows:

[0097] Step 1: Install and align the C-type dipole 1 on the foundation of the test chamber. Adjust the gap and parallelism between the upper and lower pole surfaces using a level and feeler gauge to ensure that the magnetic pole air gap meets the external dimensions of the vacuum chamber 2 and the predetermined test space requirements.

[0098] Step 2: Fix a stainless steel bearing base on the foundation below the C-type diode 1, and install a G10 epoxy fiberglass board 62 with a thickness of not less than 30mm on the bearing base to form a high-voltage insulation platform 6.

[0099] Step 3: Install the vacuum chamber 2 into the test air gap formed by the C-type diode 1, and tighten the fixing bolts after confirming the position with the laser tracker.

[0100] Step 4: Install the electrostatic deflection plate 4 inside the vacuum chamber 2 via the adjustment mechanism 8, which is used to adjust the gap or orientation of the electrostatic deflection plate 4 before or during the test.

[0101] Step 5: Install the vacuum system 3. Connect the vacuum port on the vacuum box 2 to the vacuum pump unit through the corrugated pipe, and install components such as vacuum gauges and valves.

[0102] Step 6: Install the transparent observation window 78 at the corresponding position on the side wall of the vacuum chamber 2, fix the CCD camera on the bracket at an appropriate distance from the observation window, and adjust the focus and field of view; connect the leakage current acquisition unit 71 in series in the high voltage circuit of the electrostatic deflection plate 4, and connect its output terminal to the control processing unit 76.

[0103] Step 7: Connect the C-type diode 1 excitation coil to the external excitation power supply via cable, and lay out the signal lines and power lines of detection elements such as vacuum gauges and magnetic field sensors. All signal cables are centralized to the control processing unit 76 or the data acquisition module.

[0104] Step 8: Connect the outer shell of vacuum chamber 2, C-type diode 1, the lower metal structure of high-voltage insulation platform 6, and the outer shells of all electrical equipment to the grounding busbar, and check whether the grounding resistance meets the specified requirements; according to the system interlocking logic, connect the access control switch, vacuum ready, cooling ready, magnet ready, high-voltage input allowed, and other signals to the safety interlocking circuit, and confirm that the interlocking action is correct and the emergency stop button is effective.

[0105] Step 9: After completing the above installation, conduct a vacuum leak check and motion stroke test under conditions of no high voltage and no magnetic field to confirm that the vacuum box 2 is reliably sealed and the deflection plate is adjusted smoothly without jamming. Then, gradually excite the magnet and monitor the magnetic field distribution. Then, check the insulation of the high voltage circuit and measure the linearity and zero point of the measurement link under low voltage conditions. Finally, under the premise of meeting safety conditions, carry out the high voltage insulation test and aging test of the electrostatic deflection plate 4 according to the established test formula.

[0106] During operation, the vacuum chamber 2 is first evacuated to a predetermined vacuum level by the pumping system 3 and kept stable. The C-type diode 1 is energized to establish a background magnetic field in the test air gap between the upper and lower magnetic poles, so that the electrostatic deflection plate 4 is in a magnetic field-vacuum composite environment close to the working conditions of the superconducting cyclotron accelerator take-off area. The external high-voltage power supply applies high voltage to the high-voltage electrode of the electrostatic deflection plate 4 through the high-voltage vacuum feeder 5, forming a high electric field between the deflection plate and the adjacent grounding structure, and conducting withstand voltage and aging tests.

[0107] During the experiment, the control processing unit 76 synchronously collects leakage current, vacuum level, magnetic field strength, and high-voltage status parameters under a unified time reference and uploads them to the host computer 77; the host computer 77 synchronously acquires image frames from the CCD camera. When the event criterion built into the control processing unit 76 detects a sudden change in leakage current or an exceedance of the threshold, it immediately generates a discharge event marker and notifies the host computer 77; the host computer 77 associates and stores the electrical parameter data within a preset time window before and after the event occurrence with the image frames, realizing reliable capture and traceable analysis of discharge transients.

[0108] The host computer 77 automatically manages the test process based on the preset test formula, including magnetic field setting, step voltage increase, voltage holding, event response and data archiving, and finally completes the evaluation of the insulation performance of the electrostatic deflection plate 4 according to the criteria of the formula process.

[0109] Several points should be noted: First, in the description of this application, it should be noted that, unless otherwise specified and limited, the terms "installation", "connection" and "linkage" should be interpreted broadly, and can be mechanical or electrical connection, or internal connection between two components, or direct connection. "Up", "down", "left", "right", etc. are only used to indicate relative positional relationship. When the absolute position of the described object changes, the relative positional relationship may change.

[0110] The above description is only a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiments. Any equivalent modifications or changes made by those skilled in the art based on the content disclosed in the present invention should be included within the scope of protection set forth in the claims.

Claims

1. A high voltage insulation detection device for a superconducting cyclotron electrostatic deflection plate, characterized by, include: A C-type dipole iron, with a test air gap formed between its upper and lower magnetic poles to simulate the background magnetic field of the extraction region of a superconducting cyclotron accelerator; A vacuum chamber is arranged within the test air gap; A vacuum system, connected to the vacuum chamber, is used to pump the vacuum level inside the vacuum chamber to a predetermined value and maintain it stably. An electrostatic deflection plate is installed inside the vacuum chamber; A high-voltage vacuum power supply passes through the wall of the vacuum chamber and is electrically connected to the high-voltage electrode of the electrostatic deflection plate, used to introduce high voltage between the vacuum and the atmosphere; A high-voltage insulation platform is used to support the vacuum box and electrically isolate the high-voltage components from ground potential, providing the necessary electrical clearance and equivalent creepage path; Collaborative monitoring and data acquisition system, including: Multiple acquisition units, including at least a leakage current acquisition unit, a vacuum degree acquisition unit, a magnetic field acquisition unit, a high voltage status acquisition unit, and an optical observation unit; The control and processing unit is connected to multiple acquisition units and optical observation units, respectively. The control processing unit performs synchronous sampling of leakage current, vacuum degree, magnetic field strength and high voltage state quantity under a unified time reference, and stores the image frames collected by the optical observation unit in association with the synchronous sampling data according to the timestamp; the control processing unit has a built-in event criterion module, which is used to monitor multi-source signals in real time based on preset discharge criteria, and generate discharge event markers when the criteria are met, so as to form a corresponding record of discharge events and multi-source parameters; The control processing unit is a PLC controller. The host computer receives multi-source monitoring signals with timestamps uploaded by the PLC controller. When a discharge event is detected, the PLC controller outputs an event marker. The host computer records the electrical parameters within a preset time window before and after the event and saves them in correspondence with the image frames of the same time period, so as to realize the traceable recording of the discharge process. It also includes a position adjustment mechanism, which comprises: The drive unit is located outside the vacuum chamber; The adjusting rod has one end connected to the drive unit and the other end extending through the vacuum chamber wall into the vacuum chamber. A vacuum bellows is fitted over the outside of the adjusting rod, with one end sealed to the wall of the vacuum chamber and the other end sealed to the adjusting rod. An insulating transmission component is disposed between the end of the adjusting rod that extends into the vacuum chamber and the electrostatic deflection plate, for transmitting driving force and achieving electrical isolation; The drive unit drives the electrostatic deflection plate to move within the vacuum chamber via the adjusting rod and the insulating transmission component to adjust its position.

2. The high-voltage insulation detection device for an electrostatic deflection plate of a superconducting cyclotron accelerator according to claim 1, characterized in that, The dimensions of the C-type diode's pole face are matched with the external dimensions of the vacuum chamber. The vacuum chamber is set in the central region between the upper and lower pole faces of the C-type diode, so that the electrostatic deflection plate is subjected to high-voltage testing in an approximately uniform magnetic field of 0.9 to 1.2 T.

3. The high-voltage insulation detection device for an electrostatic deflection plate of a superconducting cyclotron accelerator according to claim 1, characterized in that, The high-voltage insulation platform includes a metal support base located below and a G10 epoxy fiberglass board disposed on the metal support base, wherein the thickness of the G10 epoxy fiberglass board is at least 30mm.

4. A high-voltage insulation detection device for an electrostatic deflection plate of a superconducting cyclotron accelerator according to claim 1, characterized in that, The optical observation unit is a CCD camera, which observes the surface discharge morphology of the electrostatic deflection plate through a transparent observation window set on the side wall of the vacuum chamber. The transparent observation window is made of quartz glass or optical glass and is fixed to the vacuum chamber by a metal sealing method.

5. A high-voltage insulation detection device for an electrostatic deflection plate in a superconducting cyclotron accelerator according to claim 1, characterized in that, The discharge criteria of the event criterion include at least one or a combination of the following: leakage current exceeding a preset threshold, leakage current change rate exceeding a preset threshold, and optically observed discharge characteristics.

6. A high-voltage insulation detection device for an electrostatic deflection plate in a superconducting cyclotron accelerator according to claim 1, characterized in that, The collaborative monitoring and data acquisition system also includes a host computer, which manages the test process in a streamlined manner based on a preset test formula. The test formula includes at least magnetic field settings, step voltage ramp parameters, holding time, and event handling rules. When the control processing unit outputs a discharge event marker, the host computer records the corresponding data before and after the event and executes the corresponding handling strategy.

7. A high-voltage insulation detection device for an electrostatic deflection plate of a superconducting cyclotron accelerator according to claim 1, characterized in that, The leakage current acquisition unit includes a microammeter or current sensor connected in series with the high-voltage circuit of the electrostatic deflection plate, with a range of no more than 200μA.

8. A high-voltage insulation detection device for an electrostatic deflection plate of a superconducting cyclotron accelerator according to claim 1, characterized in that, The high-voltage vacuum power supply is a metal-ceramic sealed structure. Its vacuum side end is connected to the high-voltage electrode of the electrostatic deflection plate through a detachable connector, and the atmospheric side is provided with a shielded connector for connecting to the output cable of an external high-voltage system.

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