Apparatus and method for reducing high frequency power reflection in a large beam cyclotron

Abstract

The application discloses a device and method for reducing high-frequency power reflection of a large-beam current cyclotron, which comprises a motor compensation quantity and current intensity relation contrast table module, a beam current intensity measuring module, a PLC central controller, a motor driving module, an upper computer auxiliary adjusting module and a stepping motor module; the method comprises the following steps: establishing a current intensity compensation relation contrast table; programming the test result to the PLC and the upper computer auxiliary adjusting module; sending current current intensity measuring information to the PLC and the upper computer auxiliary adjusting module; the PLC receives a reverse sampling signal sent by a directional coupler and sends the signal to the upper computer auxiliary adjusting module; when the motor is in a closed loop working state, the PLC automatically adjusts at each 100 mu A integer multiple node; an operator determines whether manual adjustment is needed according to the reflected signal, the current intensity signal and the current direction compensation relation contrast table information displayed on the current upper computer; and the application reduces the possibility of damage of power reflection to high-frequency equipment.

Description

Technical Field

[0001] This invention belongs to the field of cyclotron technology, and particularly relates to a device and method for reducing high-frequency power reflection in large-beam cyclotrons. Background Technology

[0002] The high-frequency system is a crucial component of the cyclotron, and its stability and reliability play a key role in the cyclotron's performance. The high-frequency system of a cyclotron consists of four parts: a high-frequency power source, a transmission line system, a resonant cavity, and a low-level system. The high-frequency power source and the resonant cavity are connected by a transmission line with a coupling device. This coupling device not only feeds the high-frequency power output from the power source into the cavity to generate the high-frequency electric field required for particle acceleration, but also performs impedance transformation.

[0003] Capacitive coupling is one of the coupling methods used in cyclotrons. Capacitive coupling involves placing a capacitor in the region with the strongest electric field (i.e., near the Dee plate) to excite the resonant cavity and generate the desired field.

[0004] A resonant cavity using capacitive coupling can generally be equivalent to... Figure 5 As shown:

[0005] C c R is the coupling capacitor, while R, C, and L are the equivalent impedances of the resonant cavity itself. c When there is a beam load, from the perspective of the equivalent circuit, the equivalent parallel resistor R makes the effective impedance of the resonant cavity become R||R. c However, in the absence of a current load, R c It does not exist.

[0006] Under no-current load conditions, R, C, L, resonant frequency ω0, no-load quality factor Q0, and equivalent voltage V of the accelerating gap. eff The total power P of the cavity loss has the following relationship:

[0007]

[0008] The input impedance is: The optimal coupling condition is: Z r =Z0,Z i = 0. (Z0 is the characteristic impedance of the transmission line, and ω is the operating frequency)

[0009] make That is, the optimal coupling state is

[0010]

[0011] However, in the case of a beam load, due to Rc The generation of this phenomenon causes a change in the effective impedance of the equivalent circuit diagram, which breaks the optimal coupling state. The larger the beam current, the more obvious the impedance change and the worse the coupling state. Therefore, for high-beam-current cyclotrons, the coupling device needs to be adjusted during operation to prevent mismatch caused by changes in the coupling state. Otherwise, it will cause high-power reflection, and the reflected power will be transmitted back to the high-frequency power source along the transmission line, resulting in damage to the high-frequency power source or the transmission system.

[0012] Currently, when dealing with coupling devices in cyclotron accelerators, the coupling degree is usually not manually adjustable during accelerator operation due to practical limitations such as space constraints. Therefore, the general approach is to ensure that the cavity and power source are in an overcoupled state when there is no beam current, and then automatically transition to a near-matched state as the beam current intensity and energy increase. This method is feasible under low beam current conditions because R... c The range of variation is small, allowing for an approximate matching state. However, for high-current cyclotrons, R... c The amount of variation will be much larger, and a method must be developed to reduce high-frequency power reflection in large-beam cyclotrons; otherwise, the safety and reliability of high frequencies cannot be guaranteed. Summary of the Invention

[0013] To address the problems existing in the prior art, this invention proposes a device and method for reducing high-frequency power reflection in large-beam cyclotron accelerators. The aim is to solve the problem that existing technologies can only address the high-frequency power reflection problem in small-beam cyclotron accelerators, but cannot solve the problem of high-frequency power reflection in large-beam cyclotron accelerators under beam load, due to R... c The occurrence of this leads to a deterioration in coupling, which in turn causes a significant increase in reflected power.

[0014] To solve its technical problems, the present invention proposes the following technical solutions:

[0015] A device for reducing high-frequency power reflection in a large-beam cyclotron accelerator, characterized in that: the device includes a motor compensation and current intensity relationship lookup table module, a beam current intensity measurement module, a PLC central controller, a motor drive module, a host computer auxiliary adjustment module, and a stepper motor module; the motor compensation and current intensity relationship lookup table module is used to provide the PLC central controller with test results of the direction and distance that the motor needs to compensate for under different current intensity conditions; the beam current intensity measurement module is used to provide the PLC central controller with the current beam current intensity value; the host computer auxiliary adjustment module is used to compensate for the theoretical value and actual value of motor compensation in sudden situations. The PLC central controller receives the motor compensation amount and current intensity relationship comparison information and the beam current intensity information, calculates the current motor compensation amount, and outputs the current motor compensation amount command to the motor drive module; the PLC central controller also receives the reverse sampling signal of the directional coupler and sends the reverse sampling signal to the upper computer auxiliary adjustment module. The operator determines whether manual adjustment is needed based on the reflected signal, current intensity signal, and current intensity compensation relationship comparison table information displayed on the upper computer; it also receives the manual adjustment signal from the upper computer auxiliary adjustment module and controls the stepper motor according to the motor compensation amount sent by the upper computer auxiliary adjustment module.

[0016] Furthermore, the PLC central controller includes a reverse sampling signal receiving submodule, a current intensity compensation relationship receiving submodule, a beam intensity receiving submodule, and a calculation compensation quantum module. The calculation compensation quantum module obtains the motor compensation amount corresponding to each beam intensity from the current intensity compensation relationship receiving submodule and obtains the current beam intensity from the beam intensity receiving submodule, and then sends the corresponding motor compensation amount instruction to the motor drive module. The calculation compensation quantum module receives the current open-loop or closed-loop status information of the motor from the host computer auxiliary adjustment module, and simultaneously receives the manual motor compensation amount information sent by the host computer auxiliary adjustment module, and determines the current status. If the current status is an open-loop status, it sends an instruction to the motor drive module to control the stepper motor according to the motor compensation amount sent by the host computer auxiliary adjustment module; if the current status is a closed-loop status, it sends an instruction to the motor drive module to control the stepper motor according to the pre-test results. The reverse sampling signal receiving submodule receives the reverse sampling signal sent by the directional coupler and sends the signal to the host computer auxiliary adjustment module.

[0017] Furthermore, the host computer auxiliary adjustment module includes a reverse sampling signal receiving submodule, a current intensity compensation relationship receiving submodule, a beam intensity receiving submodule, an open-loop / closed-loop switching submodule, and a manual adjustment signal sending submodule. The open-loop / closed-loop switching submodule searches for the motor compensation amount corresponding to the current intensity in the current intensity compensation relationship receiving submodule based on the beam intensity information sent by the beam intensity receiving submodule. Then, it determines whether the current motor compensation amount has reached the preset compensation result in the lookup table based on the reverse sampling signal received by the reverse sampling signal receiving submodule. If it has not yet reached the motor compensation result in the lookup table, it selects the current state as the open-loop state and sends this state information to the calculation compensation quantum module of the PLC central controller. Subsequently, the motor movement button is clicked on the operation interface. Each click represents the motor moving one grid, and the information of each motor movement is sent to the calculation compensation quantum module of the PLC central controller.

[0018] Furthermore, the motor compensation amount and current intensity relationship lookup table module sets an ID number at each node that is an integer multiple of 100uA, along with the corresponding beam current intensity, motor compensation amount, and motor compensation direction. This lookup table information is programmed into the PLC central controller, so that the PLC central controller can control the stepper motor according to the current beam current intensity and the motor compensation amount corresponding to that current intensity in the lookup table.

[0019] A method for reducing high-frequency power reflection in a large-beam cyclotron accelerator, characterized by comprising the following steps:

[0020] Step 1: Establish a comparison table of the relationship between motor compensation and current intensity, conduct a stable test of the relationship between motor compensation and current intensity, and fill in the comparison table.

[0021] Step 2: Program the test results to the PLC central controller and send the test results to the host computer auxiliary adjustment module, and set the motor electronic ruler for feedback to make the motor movement distance more accurate;

[0022] Step 3: The accelerator is activated, and the current intensity increases from 0.

[0023] Step 4: Send the current current intensity measurement information to the PLC central controller and the host computer auxiliary adjustment module;

[0024] Step 5: The PLC central controller receives the reverse sampling signal sent by the current directional coupler and sends the reverse sampling signal to the host computer auxiliary adjustment module;

[0025] Step 6: When the motor is in closed-loop operation, the PLC central controller automatically adjusts at each node that is an integer multiple of 100μA based on the current current intensity value. The adjustment method is based on the motor's movement direction and distance in the pre-measured relationship table, thereby changing the distance between the coupling device capacitor disk and the Dee board and changing the capacitive coupling amount.

[0026] Step 7: The operator determines whether manual adjustment is required based on the information displayed on the host computer regarding the reflected signal, flow intensity signal, and flow direction compensation relationship table. If manual adjustment is not required, return to step 6. If manual adjustment is required, first select the motor in open-loop state on the operation interface and send the open-loop state signal to the PLC central controller. Then manually adjust the motor action button and send each manual adjustment signal to the PLC central controller.

[0027] Step 8: The PLC determines whether it has received a manual adjustment signal. If it has, it drives the stepper motor according to the manual adjustment instruction.

[0028] Step 9: After the operator has completed the manual adjustment, close the motor loop and return to Step 6.

[0029] Furthermore, the specific process of step one is as follows:

[0030] 1) Install the capacitive coupling device;

[0031] 2) During the process of the beam intensity increasing to the maximum intensity after the accelerator is started, the current beam intensity is obtained by the beam intensity measurement module and displayed in real time on the host computer human-machine interface.

[0032] 3) Manually operate the motor's movement direction and distance on the human-computer interaction interface, and manually adjust the motor according to the actual situation of the reflected signal to reduce the reflection and put the accelerator in a better matching state.

[0033] 4) Repeat the above process repeatedly and conduct multiple tests. Finally, a table showing the corresponding directions and distances that the motor needs to compensate for under different current intensities can be obtained.

[0034] Advantages and effects of the present invention

[0035] This invention addresses the issue of large-beam cyclotron accelerators operating under beam load, due to R... c To address the problem of deteriorated coupling and consequently a significant increase in reflected power caused by the generation of [something], a novel method for reducing high-frequency power reflection in high-current cyclotron accelerators was designed. This method is independent of the existing low-level system and incorporates an automatically adjustable coupling capacitor C. cThe coupling loop monitors the beam current through a beam current measurement system. As the beam current of the large-beam cyclotron accelerator gradually increases, this coupling loop can adjust the coupling capacitance C between the high-frequency power source and the resonant cavity in real time according to the change in current. c The size of the two is adjusted to ensure good coupling and matching, which greatly reduces the possibility of power reflection damaging high-frequency equipment, increases the feed power between the high-frequency power source and the resonant cavity, reduces power reflection, and effectively improves the stability and reliability of the high-frequency system and even the cyclotron. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of the device of the present invention for reducing high-frequency power reflection in a large-beam cyclotron accelerator;

[0037] Figure 2a This is a functional block diagram of the host computer auxiliary adjustment module of the present invention;

[0038] Figure 2b This is a schematic diagram of the human-machine interface of the host computer auxiliary adjustment module of the present invention;

[0039] Figure 3 This is a functional block diagram of the PLC central controller of the present invention;

[0040] Figure 4 This is a table showing the relationship between motor compensation and current intensity in this invention.

[0041] Figure 5 This is a schematic diagram of a capacitively coupled resonant cavity. Detailed Implementation

[0042] Design principle of the invention

[0043] 1. Design difficulties of this invention

[0044] The challenge lies in dealing with large-beam cyclotrons rather than small-beam cyclotrons, and the reflections in large-beam cyclotrons are dynamic and even uncontrollable. Small-beam cyclotrons typically handle coupling capacitance using an "overcoupling" method, predicting the current capacitance (R) when there is no current and then applying it in parallel with R. c The resistance changes to the desired value, but this "pre-compensation" method is limited to situations where the beam current is small and R... c In situations where the value changes little, for large-beam cyclotron accelerators, the beam load changes continuously with the increasing current intensity during startup, resulting in not only significant load variations but also load fluctuations. If the overcoupling methods used for small-beam cyclotron accelerators are applied, the matching will be very poor at startup, potentially preventing power input and beam output. The principle behind the continuously changing load is as follows: Figure 5 As shown, in the case of a beam load, due to Rc The generation of this leads to a change in the effective impedance of the equivalent circuit diagram, and as the current intensity increases during accelerator startup, R... c The value of R also gradually increases and changes continuously, because c The continuous changes in load worsen the coupling matching effect, leading to a continuous increase in the value sampled back from the directional coupler. The load fluctuations or uncontrollability are due to uncontrollable environmental factors, resulting in a discrepancy between theory and practice. As the beam current increases during accelerator startup, the impedance change becomes more pronounced, and the coupling state deteriorates. If the coupling device is not effectively adjusted during accelerator startup, high-power reflection will occur. The reflected power will travel along the transmission line back to the high-frequency power source, causing damage to the high-frequency power source or transmission system.

[0045] 2. Dynamic control principle

[0046] First, the design principle combines dynamic and static design. Dynamic design involves real-time beam intensity measurement and real-time motor movement. Static design involves pre-establishing a reference table showing the relationship between motor compensation and current intensity. The combination of dynamic and static design means that real-time beam intensity measurement and motor compensation rely on this reference table, which has been repeatedly tested and proven effective for each current intensity. Compared to methods that calculate motor compensation based on the current current intensity instantly, this method offers faster response and lower latency. Instantaneous calculations of motor compensation are often slow and have high latency due to their complex algorithms, and therefore may not effectively reduce reflected power. The motor compensation values ​​given in the reference table for each current intensity value are conclusions drawn from repeated testing and proven effectiveness in reducing reflected power.

[0047] Secondly, the design principle combines theoretical design and manual adjustment. Theoretical design refers to a design derived from experience and theory within a certain range. In this invention, the theoretical design is based on a "motor compensation amount and current intensity relationship comparison table." Manual adjustment is based on a "host computer-assisted adjustment" design. Without theoretical design, the host computer-assisted adjustment module has no basis for judgment. For example, if the current current intensity is 100μA, looking up the comparison table, the reverse sampling signal after motor compensation should show a decreasing trend, and the reflection should decrease, even approaching zero. However, if the reflected signal is not in a range close to "0" but exceeds this range significantly, it indicates that the theoretically designed motor compensation amount cannot solve the problem of high current reflected power. This is because the theoretical design does not consider environmental factors under sudden conditions. The increase in reflected power caused by environmental factors under sudden conditions cannot be reduced using conventional motor compensation amounts. Determining the appropriate motor compensation amount to reduce reflected power under sudden conditions cannot be obtained through automatic control; only manual adjustment can be used until the reflected power is reduced to an acceptable range. Therefore, theoretical design must be combined with manual adjustment to perfectly solve various problems. Similarly, manual adjustment also relies on theoretical design. Without a theoretical design, there is no basis for judgment when making manual adjustments.

[0048] Based on the above-mentioned inventive principles, this invention designs a device for reducing high-frequency power reflection in large-beam cyclotron accelerators, such as... Figure 1 , Figure 2a , Figure 2b , Figure 3 , Figure 4 As shown, the device is characterized by the following: it includes a motor compensation and current intensity relationship comparison table module, a beam current intensity measurement module, a PLC central controller, a motor drive module, a host computer auxiliary adjustment module, and a stepper motor module; the motor compensation and current intensity relationship comparison table module is used to provide the PLC central controller with test results of the direction and distance that the motor needs to compensate for under different current intensities; the beam current intensity measurement module is used to provide the PLC central controller with the current beam current intensity value; the host computer auxiliary adjustment module is used to compensate for the deviation between the theoretical value and the actual value of the motor compensation in sudden situations; the PLC... The central controller receives the motor compensation amount and current intensity relationship comparison information and the beam current intensity information, calculates the current motor compensation amount, and outputs the current motor compensation amount command to the motor drive module. The PLC central controller also receives the reverse sampling signal from the directional coupler and sends the reverse sampling signal to the host computer auxiliary adjustment module. The operator determines whether manual adjustment is needed based on the reflected signal, current intensity signal, and current intensity compensation relationship comparison table information displayed on the host computer. It also receives the manual adjustment signal from the host computer auxiliary adjustment module and controls the stepper motor according to the motor compensation amount sent by the host computer auxiliary adjustment module.

[0049] Furthermore, the PLC central controller includes a reverse sampling signal receiving submodule, a current intensity compensation relationship receiving submodule, a beam intensity receiving submodule, and a calculation compensation quantum module. The calculation compensation quantum module obtains the motor compensation amount corresponding to each beam intensity from the current intensity compensation relationship receiving submodule and obtains the current beam intensity from the beam intensity receiving submodule, and then sends the corresponding motor compensation amount instruction to the motor drive module. The calculation compensation quantum module receives the current open-loop or closed-loop status information of the motor from the host computer auxiliary adjustment module, and simultaneously receives the manual motor compensation amount information sent by the host computer auxiliary adjustment module, and determines the current status. If the current status is an open-loop status, it sends an instruction to the motor drive module to control the stepper motor according to the motor compensation amount sent by the host computer auxiliary adjustment module; if the current status is a closed-loop status, it sends an instruction to the motor drive module to control the stepper motor according to the pre-test results. The reverse sampling signal receiving submodule receives the reverse sampling signal sent by the directional coupler and sends the signal to the host computer auxiliary adjustment module.

[0050] Furthermore, the host computer auxiliary adjustment module includes a reverse sampling signal receiving submodule, a current intensity compensation relationship receiving submodule, a beam intensity receiving submodule, an open-loop / closed-loop switching submodule, and a manual adjustment signal sending submodule. The open-loop / closed-loop switching submodule searches for the motor compensation amount corresponding to the current intensity in the current intensity compensation relationship receiving submodule based on the beam intensity information sent by the beam intensity receiving submodule. Then, it determines whether the current motor compensation amount has reached the preset compensation result in the lookup table based on the reverse sampling signal received by the reverse sampling signal receiving submodule. If it has not yet reached the motor compensation result in the lookup table, it selects the current state as the open-loop state and sends this state information to the calculation compensation quantum module of the PLC central controller. Subsequently, the motor movement button is clicked on the operation interface. Each click represents the motor moving one grid, and the information of each motor movement is sent to the calculation compensation quantum module of the PLC central controller.

[0051] Furthermore, the motor compensation amount and current intensity relationship lookup table module sets an ID number at each node that is an integer multiple of 100uA, along with the corresponding beam current intensity, motor compensation amount, and motor compensation direction. This lookup table information is programmed into the PLC central controller, so that the PLC central controller can control the stepper motor according to the current beam current intensity and the motor compensation amount corresponding to that current intensity in the lookup table.

[0052] A method for reducing high-frequency power reflection in a large-beam cyclotron accelerator, characterized by comprising the following steps:

[0053] Step 1: Establish a comparison table of the relationship between motor compensation and current intensity, conduct a stable test of the relationship between motor compensation and current intensity, and fill in the comparison table.

[0054] Step 2: Program the test results to the PLC central controller and send the test results to the host computer auxiliary adjustment module, and set the motor electronic ruler for feedback to make the motor movement distance more accurate;

[0055] Step 3: The accelerator is activated, and the current intensity increases from 0.

[0056] Step 4: Send the current current intensity measurement information to the PLC central controller and the host computer auxiliary adjustment module;

[0057] Step 5: The PLC central controller receives the reverse sampling signal sent by the current directional coupler and sends the reverse sampling signal to the host computer auxiliary adjustment module;

[0058] Step 6: When the motor is in closed-loop operation, the PLC central controller automatically adjusts at each node that is an integer multiple of 100μA based on the current current intensity value. The adjustment method is based on the direction and distance of the motor's movement in the pre-measured relationship table, thereby changing the distance between the coupling device capacitor disk and the DEE board and changing the capacitive coupling amount.

[0059] Step 7: The operator determines whether manual adjustment is required based on the information displayed on the host computer regarding the reflected signal, flow intensity signal, and flow direction compensation relationship table. If manual adjustment is not required, return to step 6. If manual adjustment is required, first select the motor in open-loop state on the operation interface and send the open-loop state signal to the PLC central controller. Then manually adjust the motor action button and send each manual adjustment signal to the PLC central controller.

[0060] Step 8: The PLC determines whether it has received a manual adjustment signal. If it has, it drives the stepper motor according to the manual adjustment instruction.

[0061] Step 9: After the operator has completed the manual adjustment, close the motor loop and return to Step 6.

[0062] Furthermore, the specific process of step one is as follows:

[0063] 1) Install the capacitive coupling device;

[0064] 2) During the process of the beam intensity increasing to the maximum intensity after the accelerator is started, the current beam intensity is obtained by the beam intensity measurement module and displayed in real time on the host computer human-machine interface.

[0065] 3) Manually operate the motor's movement direction and distance on the human-computer interaction interface, and manually adjust the motor according to the actual situation of the reflected signal to reduce the reflection and put the accelerator in a better matching state.

[0066] 4) Repeat the above process repeatedly and conduct multiple tests. Finally, a table showing the corresponding directions and distances that the motor needs to compensate for under different current intensities can be obtained.

[0067] Example 1

[0068] This embodiment of the device includes a motor compensation and current intensity relationship lookup table module, a beam current intensity measurement module, a PLC central controller, a motor drive module, a host computer auxiliary adjustment module, and a stepper motor module. The motor compensation and current intensity relationship lookup table module provides the PLC central controller with test results of the direction and distance that the motor needs to compensate for under different current intensities. The beam current intensity measurement module provides the PLC central controller with the current beam current intensity value. The host computer auxiliary adjustment module compensates for the deviation between the theoretical and actual values ​​of the motor compensation in sudden situations. The PLC central controller receives the motor compensation and current intensity relationship lookup information and the beam current intensity information, calculates the current motor compensation amount, and outputs the current motor compensation amount command to the motor drive module. The PLC central controller also receives the reverse sampling signal from the directional coupler and sends this reverse sampling signal to the host computer auxiliary adjustment module. The operator determines whether manual adjustment is needed based on the reflected signal, current intensity signal, and current intensity compensation relationship lookup table information displayed on the host computer. The implementation method is as follows:

[0069] First, based on the physical design of the resonant cavity and the actual space, the installation position of the capacitive coupling device is determined. The capacitive coupling device is installed by opening a hole at the lower end of the resonant cavity. The distance between the capacitor disk of the coupling device and the Dee plate can be adjusted by adjusting the movement of the motor, thereby changing the amount of capacitive coupling.

[0070] Secondly, the coupling degree needs to be adjusted based on the current intensity parameter. Therefore, a beam current intensity detection system is required. When the current intensity is a multiple of 100μA, the coupling capacitor of the coupling device is adjusted. Considering that changes in the coupling capacitor will also affect the operating frequency, the tuning loop of the low-level system is kept running normally to maintain a constant operating frequency.

[0071] Third, the relative compensation amount required for the coupling capacitance under different current intensities, especially in the range near integer multiples of 100μA, was tested. The motor movement data at each compensation point was recorded and input into the PLC. This allows the PLC controller to automatically control the motor movement distance for every 100μA change in current intensity, and an electronic ruler is set for feedback to make the motor movement distance more accurate. To further improve the safety and stability of this method and prevent uncontrollable situations, an alternative method is proposed: using a directional coupler to obtain reflected sampling signals from the transmission line, which can be displayed in real time on the host computer's human-machine interface. The human-machine interface also allows manual operation of the motor's movement direction and distance. After each automatic adjustment at the compensation point, manual fine-tuning can be selected based on the real-time reflection changes, thus better ensuring the safety of the high-frequency system.

[0072] Fourth, the implementation of sampling signal display on the host computer human-machine interface: The sampling signal is an analog quantity. The sampling signal is transmitted to the PLC for AD conversion, and then the voltage signal is converted into a success rate signal by formula and reflected on the human-machine interface, so as to realize the real-time monitoring of the magnitude of the reflected power.

[0073] Fifth, the implementation of automatic motor adjustment: the human-machine interface is selected to be in closed-loop mode, and a stepper motor can be selected. The PLC issues instructions at each compensation point based on the data of the beam measurement system. By sending pulse signals to control the stepper motor's step angle, the movement direction and distance of the stepper motor are controlled. An electronic ruler is set to provide feedback on the motor's movement to prevent step loss.

[0074] Sixth, implementation of manual motor adjustment: Select open-loop mode on the human-machine interface, select the direction and step distance of motor movement according to the actual situation, the host computer sends the instruction to the lower PLC, and the PLC then controls the motor driver to realize the function of motor movement.

[0075] It should be emphasized that the above specific embodiments are merely explanations of the present invention and are not intended to limit the present invention. After reading this specification, those skilled in the art can make modifications to the above embodiments without contributing any inventive step, but as long as they are within the scope of the claims of the present invention, they are protected by patent law.

Claims

1. A device for reducing high-frequency power reflection in a large-beam cyclotron accelerator, characterized in that: The device includes a motor compensation and current intensity relationship lookup table module, a beam current intensity measurement module, a PLC central controller, a motor drive module, a host computer auxiliary adjustment module, and a stepper motor module. The motor compensation and current intensity relationship lookup table module provides the PLC central controller with test results of the direction and distance the motor needs to compensate for under different current intensities. The beam current intensity measurement module provides the PLC central controller with the current beam current intensity value. The host computer auxiliary adjustment module compensates for deviations between the theoretical and actual motor compensation values ​​in sudden situations. The PLC central controller receives the motor compensation and current intensity relationship lookup information and the beam current intensity information, calculates the current motor compensation amount, and outputs the current motor compensation amount command to the motor drive module. The PLC central controller also receives the reverse sampling signal from the directional coupler and sends this reverse sampling signal to the host computer auxiliary adjustment module. The operator determines whether manual adjustment is needed based on the reflected signal, current intensity signal, and current intensity compensation relationship lookup table information displayed on the host computer. When the motor is in closed-loop operation, the PLC central controller automatically adjusts at every node that is an integer multiple of 100μA based on the current current intensity value. The adjustment method is based on the direction and distance of the motor's movement in the pre-measured relationship table, thereby changing the distance between the coupling device capacitor disk and the DEE board and changing the capacitive coupling amount.

2. The device for reducing high-frequency power reflection in a large-beam cyclotron accelerator according to claim 1, characterized in that: The PLC central controller includes a reverse sampling signal receiving submodule, a current intensity compensation relationship receiving submodule, a beam intensity receiving submodule, and a calculation compensation quantum module. The calculation compensation quantum module obtains the motor compensation amount corresponding to each beam intensity from the current intensity compensation relationship receiving submodule and obtains the current beam intensity from the beam intensity receiving submodule, and then sends the corresponding motor compensation amount instruction to the motor drive module. The calculation compensation quantum module receives the current open-loop or closed-loop status information of the motor from the host computer auxiliary adjustment module, and simultaneously receives the manual motor compensation amount information sent by the host computer auxiliary adjustment module, and determines the current status. If the current status is an open-loop status, it sends an instruction to the motor drive module to control the stepper motor according to the motor compensation amount sent by the host computer auxiliary adjustment module; if the current status is a closed-loop status, it sends an instruction to the motor drive module to control the stepper motor according to the pre-test results. The reverse sampling signal receiving submodule receives the reverse sampling signal sent by the directional coupler and sends the signal to the host computer auxiliary adjustment module.

3. The device for reducing high-frequency power reflection in a large-beam cyclotron accelerator according to claim 1, characterized in that: The host computer auxiliary adjustment module includes a reverse sampling signal receiving submodule, a current intensity compensation relationship receiving submodule, a beam intensity receiving submodule, an open-loop / closed-loop switching submodule, and a manual adjustment signal sending submodule. The open-loop / closed-loop switching submodule searches for the motor compensation amount corresponding to the current intensity in the current intensity compensation relationship receiving submodule based on the beam intensity information received by the beam intensity receiving submodule. Then, it determines whether the current motor compensation amount has reached the preset compensation result in the lookup table based on the reverse sampling signal received by the reverse sampling signal receiving submodule. If it has not reached the motor compensation result in the lookup table, it selects the current state as the open-loop state and sends the state information to the calculation compensation quantum module of the PLC central controller. Then, click the motor movement button on the operation interface. Each click represents the motor moving one grid, and the information of each motor movement is sent to the calculation and compensation quantum module of the PLC central controller.

4. The device for reducing high-frequency power reflection in a large-beam cyclotron accelerator according to claim 1, characterized in that: The motor compensation amount and current intensity relationship lookup table module sets an ID number at each node that is an integer multiple of 100uA, along with the corresponding beam current intensity, motor compensation amount, and motor compensation direction. This lookup table information is programmed into the PLC central controller, so that the PLC central controller can control the stepper motor according to the current beam current intensity and the motor compensation amount corresponding to that current intensity in the lookup table.

5. A method for reducing high-frequency power reflection in a large-beam cyclotron accelerator, based on the apparatus for reducing high-frequency power reflection in any one of claims 1-4, characterized in that, Includes the following steps: Step 1: Establish a comparison table of the relationship between motor compensation and current intensity, conduct a stable test of the relationship between motor compensation and current intensity, and fill in the comparison table. Step 2: Program the test results to the PLC central controller and send the test results to the host computer auxiliary adjustment module, and set the motor electronic ruler for feedback to make the motor movement distance more accurate; Step 3: The accelerator is activated, and the current intensity increases from 0. Step 4: Send the current current intensity measurement information to the PLC central controller and the host computer auxiliary adjustment module; Step 5: The PLC central controller receives the reverse sampling signal sent by the current directional coupler and sends the reverse sampling signal to the host computer auxiliary adjustment module; Step 6: When the motor is in closed-loop operation, the PLC central controller automatically adjusts at each node that is an integer multiple of 100μA based on the current current intensity value. The adjustment method is based on the direction and distance of the motor's movement in the pre-measured relationship table, thereby changing the distance between the coupling device capacitor disk and the DEE board and changing the capacitive coupling amount. Step 7: The operator determines whether manual adjustment is required based on the information displayed on the host computer regarding the reflected signal, flow intensity signal, and flow direction compensation relationship table. If manual adjustment is not required, return to step 6. If manual adjustment is required, first select the motor in open-loop state on the operation interface and send the open-loop state signal to the PLC central controller. Then manually adjust the motor action button and send each manual adjustment signal to the PLC central controller. Step 8: The PLC determines whether it has received a manual adjustment signal. If it has, it drives the stepper motor according to the manual adjustment instruction. Step 9: After the operator has completed the manual adjustment, close the motor loop and return to Step 6.

6. The method for reducing high-frequency power reflection in a large-beam cyclotron accelerator according to claim 5, characterized in that, The specific process of step one is as follows: 1) Install a capacitive coupling device; 2) During the process of the beam intensity increasing to the maximum intensity after the accelerator is started, the current beam intensity is obtained by the beam intensity measurement module and displayed in real time on the host computer human-machine interface. 3) Manually operate the direction and distance of the motor's movement on the human-computer interaction interface, and manually adjust the motor according to the actual situation of the reflected signal to reduce the reflection and put the accelerator in a better matching state. 4) Repeat the above process repeatedly and conduct multiple tests. Finally, a table showing the corresponding directions and distances that the motor needs to compensate for under different flow intensities can be obtained.

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