Vacuum regulating valve pressure control system and control method thereof

Abstract

The invention provides a vacuum regulating valve pressure control system and a control method thereof, and relates to the technical field of vacuum regulating valve pressure control. The control method comprises the steps that after a specified rotating speed is obtained through a valve rotating speed model, a valve plate of the vacuum regulating valve is controlled to rotate to a specified angle position according to the specified rotating speed; the valve rotating speed model is established based on the PWM pulse frequency and the Simoid function. According to the control method of the vacuum regulating valve pressure control system, the problem that an existing vacuum regulating valve pressure control system cannot meet the response speed and stability required by a production line is solved, and the effect of improving the response speed and stability of the system is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of vacuum regulating valve pressure control, and in particular to a vacuum regulating valve pressure control system and a control method thereof. Background Art

[0002] The regulating valve can effectively control the pressure of the vacuum chamber under different vacuum environments and is widely used in the fields of semiconductor technology, new display manufacturing and solar energy. In the vacuum system, the regulating valve is installed at the air inlet or exhaust port and connected to the vacuum chamber equipment. The pressure is controlled by adjusting the valve plate through the control algorithm. However, the current vacuum regulating valve pressure control system fails to take into account both speed and accuracy when controlling the rotation of the valve plate. When the valve plate rotates at a higher speed, its actual position often has a large error that is difficult to control from the specified position, resulting in unstable cavity pressure of the vacuum chamber, which makes the current vacuum regulating valve pressure control system unable to meet the response speed and stability required by the production line.

[0003] There is currently no effective technical solution to the above problems. Summary of the invention

[0004] The purpose of the present invention is to provide a vacuum regulating valve pressure control system and a control method thereof, which solves the problem that the current vacuum regulating valve pressure control system cannot meet the response speed and stability required by the production line, thereby achieving the effect of improving the system response speed and stability.

[0005] In the first aspect, the present invention provides a control method for a vacuum regulating valve pressure control system, comprising obtaining a specified speed through a valve speed model, and then controlling the valve plate of the vacuum regulating valve to rotate to a specified angular position according to the specified speed; the valve speed model is established based on PWM pulse frequency and Simoid function.

[0006] The control method of the vacuum regulating valve pressure control system of the present invention utilizes a preset valve speed model to achieve better control of the valve plate speed, thereby ensuring that the valve plate can reach the specified position faster and more accurately, thereby improving the response speed and stability of the system.

[0007] Furthermore, the specific expression of the Simoid function is: ; in, About Simoid function, is less than integer variable, is the preset number of acceleration times; The specific expression of the valve speed model is: ; in, About The valve speed model, is the minimum value of PWM pulse frequency, It is the maximum value of PWM pulse frequency.

[0008] Further, obtaining the specified speed through the valve speed model includes calculating the specified speed according to the following formula: ; in, is the specified speed, are preset parameters.

[0009] Further, when the vacuum regulating valve is powered on, the following steps are performed: A1. Controlling the valve plate to rotate at the specified speed through a stepper driver; A2. Detect the blocking of the valve plate and control the valve plate to stop rotating when the valve plate is detected to be blocked; A3. Using the valve speed model to control the stepper driver according to a preset number of steps to drive the valve plate to reverse at the specified speed; A4. After the valve plate stops rotating, the vacuum regulating valve pressure control system is restored to an initial state.

[0010] This step ensures that the system returns to a known, controllable initial state each time it is powered on, laying the foundation for subsequent precise control.

[0011] Furthermore, the specific steps in step A2 include: A21. Detect the blocking condition of the valve plate according to the following steps: A211 obtains the two-phase current difference of the stepper driver; A212. When the two-phase current difference increases, it is determined that the valve plate is blocked and the valve plate is controlled to stop rotating.

[0012] This method can respond at an early stage when the valve plate is blocked, effectively preventing the valve plate from being damaged due to continuous force. At the same time, the valve plate is reversed a certain number of steps using the stall as a signal, so that the valve plate can return to zero more accurately.

[0013] Furthermore, the step of setting the initial state of the vacuum regulating valve pressure control system includes: B1. Controlling the valve plate to rotate at the specified speed so that the vacuum regulating valve is closed; B2. Using the valve speed model to control the valve plate to rotate 90° at the specified speed and record the cavity pressure of the vacuum chamber corresponding to the valve plate at different angular positions, to obtain a data table of the angular position of the valve plate and the cavity pressure of the vacuum chamber; B3. Control the angular position of the valve plate according to the data table so that the vacuum chamber reaches a specified chamber pressure.

[0014] In a second aspect, the present invention provides a vacuum regulating valve pressure control system, comprising a stepper driver and a vacuum regulating valve, wherein the stepper driver is used to obtain a specified speed through a valve speed model, and then control the valve plate of the vacuum regulating valve to rotate to a specified angular position according to the specified speed; the valve speed model is established based on PWM pulse frequency and Simoid function.

[0015] The device provided by the present invention uses this method, and the system can accurately control the rotation speed and angular position of the valve plate, thereby achieving accurate regulation of the vacuum chamber pressure.

[0016] Furthermore, it also includes a return-to-zero controller, which is used to perform the following steps when the vacuum regulating valve is powered on: A1. Controlling the valve plate to rotate at the specified speed through a stepper driver; A2. Detect the blocking of the valve plate and control the valve plate to stop rotating when the valve plate is detected to be blocked; A3. Using the valve speed model to control the stepper driver according to a preset number of steps to drive the valve plate to reverse at the specified speed; A4. After the valve plate stops rotating, the vacuum regulating valve pressure control system is restored to an initial state.

[0017] Furthermore, when the return-to-zero controller is used to detect the blocking condition of the valve plate, the following steps are performed: A21 detects the blocking condition of the valve plate according to the following steps: A211 obtains the two-phase current difference of the stepper driver; A212. When the two-phase current difference increases, it is determined that the valve plate is blocked and the valve plate is controlled to stop rotating.

[0018] Furthermore, it also includes an initialization controller, wherein the initialization controller is used to perform the following steps: B1. Using the valve speed model to control the valve plate to rotate at the specified speed to close the vacuum regulating valve; B2. Using the valve speed model to control the valve plate to rotate 90° at the specified speed and record the cavity pressure of the vacuum chamber corresponding to the valve plate at different angular positions, to obtain a data table of the angular position of the valve plate and the cavity pressure of the vacuum chamber; B3. Control the angular position of the valve plate according to the data table so that the vacuum chamber reaches a specified chamber pressure.

[0019] From the above, it can be seen that the control method of the vacuum regulating valve pressure control system provided by the present invention establishes a valve speed model based on PWM pulse frequency and Simoid function to obtain the ability to control the valve to accurately reach the specified angular position at a faster and smoother speed, thereby effectively reducing the error between its actual position and the specified position, making the cavity pressure of the vacuum chamber more stable, thereby achieving the effect of improving the system response speed and stability.

[0020] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or be understood by implementing the embodiments of the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the written description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 A flow chart of a control method for a vacuum regulating valve pressure control system provided in an embodiment of the present invention.

[0022] Figure 2 A schematic structural diagram of a vacuum regulating valve pressure control system provided in an embodiment of the present invention.

[0023] Description of labels: 100, stepping driver; 200, vacuum regulating valve; 300, return to zero controller; 400, initialization controller. DETAILED DESCRIPTION

[0024] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. The components of the embodiments of the present invention generally described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents the selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present invention.

[0025] It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings. At the same time, in the description of the present invention, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0026] In the vacuum regulating valve pressure control system, the vacuum chamber needs to switch from one pressure state to another in a very short time to adapt to different process steps. However, when the valve plate of the existing vacuum regulating valve system rotates at high speed, position errors often occur, resulting in the pressure of the vacuum chamber being unable to stabilize at the expected value. This instability will directly affect the quality and production efficiency of the product.

[0027] For this, please refer to the attached Figure 1 The present invention provides a control method for a vacuum regulating valve pressure control system, comprising obtaining a specified speed through a valve speed model, and then controlling a valve plate of the vacuum regulating valve to rotate to a specified angular position according to the specified speed; the valve speed model is established based on a PWM pulse frequency and a Simoid function.

[0028] The valve speed model of this embodiment can realize smooth acceleration of the valve plate from a stationary state to a maximum speed, and then smooth deceleration when approaching a target position, thereby avoiding the problem of sudden acceleration and deceleration in traditional control methods.

[0029] The valve speed model is closely related to the stepper driver and the vacuum control valve. The stepper driver controls the rotation of the stepper driver by adjusting the PWM signal according to the specified speed output by the model. The valve plate of the vacuum control valve achieves precise angular positioning according to the rotation of the stepper driver. This connection enables the system to improve response speed while maintaining accuracy.

[0030] The technical solution of the present application realizes precise control of the valve plate through the valve speed model. First, the system calculates the required valve plate angle position based on the current vacuum chamber pressure and the target pressure. Then, a smooth speed curve is generated by the valve speed model. Finally, the stepper driver controls the valve plate of the vacuum regulating valve to move from the current position to the target position according to this speed curve.

[0031] During the rotation of the valve plate, the system continuously monitors the vacuum chamber pressure and the valve plate position. If it detects that the pressure change trend is not in line with expectations, the system can adjust the speed curve in real time to ensure that the target pressure is finally reached. This closed-loop control method greatly improves the stability and accuracy of the system.

[0032] Compared with the traditional control method, the technical solution of the present application has the following advantages: First, by combining PWM pulse frequency and Sigmoid function, more precise and smooth speed control is achieved. This not only improves the accuracy of valve plate position control, but also reduces the mechanical stress and wear of the system, extending the service life of the equipment.

[0033] Secondly, the introduction of the valve speed model enables the system to adaptively adjust control parameters according to different working conditions, improving the flexibility and adaptability of the system.

[0034] Finally, this control method significantly improves the response speed and stability of the system, making pressure control more reliable and efficient, and can better meet the stringent requirements of semiconductor processes, new display manufacturing, solar energy and other fields.

[0035] In practical applications, the range of PWM pulse frequency can be set, such as 100Hz to 10kHz, to meet different speed requirements. At the same time, the accuracy of the angular position can be set according to actual needs, such as ±0.1 degrees. In addition, this method can also be used in combination with other control technologies, such as adding a simple feedback mechanism to check the actual position after each adjustment and make fine adjustments if there is an error.

[0036] In order to specifically illustrate the implementation of the present application, the following takes a photolithography device in a semiconductor manufacturing process as an example. A vacuum regulating valve is installed on a vacuum chamber of the photolithography device to accurately control the pressure in the chamber.

[0037] First, the valve speed model is established. When the vacuum chamber pressure needs to be adjusted from 100Pa to 50Pa, the angle that the valve plate needs to rotate is calculated based on the pressure change, assuming it is 30°. Then, the valve speed model is used to obtain the speed curve of the valve plate. According to the speed curve, the valve plate is controlled to rotate at different speeds during the movement process and finally reach the angle position.

[0038] Next, the calculated specified speed is converted into the corresponding PWM pulse frequency and sent to the stepper driver. The stepper driver drives the valve plate of the vacuum regulating valve to accurately rotate to the specified angle position according to the received PWM signal. During the whole process, the system continuously monitors the actual pressure of the vacuum chamber. If a deviation is found between the actual pressure and the target pressure, it will be fine-tuned according to the valve speed model to ensure that the pressure is stable at 50Pa.

[0039] By using a valve speed model based on PWM pulse frequency and Sigmoid function, the system can accurately adjust the vacuum chamber pressure from 100Pa to 50Pa within 0.1 seconds while maintaining a pressure stability of ±0.1Pa. This high-speed response and precise control capability significantly improves the efficiency and quality of the lithography process.

[0040] Compared with the existing technology, the traditional vacuum regulating valve control system usually adopts a linear control method, which is difficult to accurately describe the nonlinear characteristics of the valve plate movement. This leads to a large position error during high-speed adjustment, which in turn affects the accuracy of pressure control. For example, under the same conditions, a certain existing technology takes 0.5 seconds to complete the pressure adjustment, and the pressure fluctuation can reach ±1Pa.

[0041] The valve speed model based on PWM pulse frequency and Sigmoid function introduced in this application can more accurately describe the motion characteristics of the valve plate, especially the nonlinear behavior at high speed. This enables the system to significantly improve the accuracy of position control while maintaining high-speed response. Therefore, this application not only solves the contradiction between speed and accuracy, but also greatly improves the overall performance and reliability of the vacuum regulating valve, as well as the stability of the system's pressure control.

[0042] In addition, the control methods in the prior art are often difficult to adapt to vacuum systems of different specifications. The technical solution of the present application can flexibly adapt to vacuum systems of different volumes and pressure ranges through adjustable model parameters, greatly improving the versatility and adaptability of the system.

[0043] Finally, the traditional method is prone to pressure fluctuations and mechanical shocks during high-speed adjustment, affecting system stability and service life. The smooth speed control of this application effectively solves this problem, not only improving the stability of pressure control, but also extending the service life of the equipment and reducing maintenance costs.

[0044] Specifically, the specific expression of the Simoid function is: ; in, About Simoid function, is less than integer variable, is the preset number of acceleration times; The specific expression of the valve speed model is: ; in, About The valve speed model, is the minimum value of PWM pulse frequency, It is the maximum value of PWM pulse frequency.

[0045] Specifically, obtaining the specified speed through the valve speed model includes calculating the specified speed according to the following formula: ; in, is the specified speed, are preset parameters.

[0046] It should be noted that the preset parameter needs to be determined according to the specifications of the stepper driver actually used, and its value range is generally 1-256. For example, if the stepper driver uses a 1.8° stepper motor, the value is 32, but it is not limited to this.

[0047] In some embodiments, when the vacuum regulating valve is powered on, the following steps are performed: A1. The valve plate is controlled to rotate at a specified speed through a stepper driver; A2. Detect the blocking of the valve plate and control the valve plate to stop rotating when the valve plate is detected to be blocked; A3. Use the valve speed model to control the stepper driver to drive the valve plate to reverse at a specified speed according to the preset number of steps; A4. After the valve plate stops rotating, restore the vacuum regulating valve pressure control system to its initial state.

[0048] In this embodiment, the valve plate is controlled to rotate at a specified speed by a stepper driver, which ensures the accuracy and controllability of the valve plate movement. Secondly, the system will detect the blocking of the valve plate. Once the valve plate is detected to be blocked, the valve plate will be immediately controlled to stop rotating. This step can protect the safe operation of the stepper driver and improve the safety and reliability of the system. Then, the valve speed model is used to control the stepper driver to drive the valve plate to reverse at a specified speed according to the preset number of steps. This step ensures that the valve plate returns to its initial position accurately by accurately controlling the number of reversal steps. Finally, after the valve plate stops rotating, the vacuum regulating valve pressure control system is restored to its initial state. This step ensures that the system can return to a known and controllable initial state each time it is powered on, laying the foundation for subsequent precise control.

[0049] In practice, there are many ways to control the valve plate to rotate at a specified speed using a stepper driver. For example, a pulse width modulation (PWM) signal can be used to control the speed of the stepper driver, and different speeds can be achieved by adjusting the frequency and duty cycle of the PWM signal. Another method is to use micro-stepping drive technology to achieve more precise speed control by subdividing each step of the stepper driver.

[0050] The detection of valve plate stalling can be achieved by monitoring the current change of the stepper driver. When the valve plate is blocked, the motor current will suddenly increase. A current threshold can be set, and when the current exceeds this threshold, the motor will stop running immediately. In addition, the actual position of the valve plate can also be monitored by the encoder. If it is detected that the valve plate position remains unchanged for a long time but the motor is still running, it is determined to be stalled.

[0051] Using the valve speed model to control the valve plate reversal is a key point of this solution. This model can be established based on the PWM pulse frequency and the Sigmoid function. Through this model, the reversal speed and position of the valve plate can be accurately controlled. For example, the preset number of steps for reversal can be set to 1000 steps, and the specific speed of each step can be calculated through the model to achieve a smooth acceleration and deceleration process.

[0052] The association and interaction between these steps form a closed-loop control system. The stepper driver controls the valve plate rotation and detects the stall situation in real time to ensure the safety of the system. Once a stall is detected, the system stops immediately and performs a reverse operation. This rapid response mechanism greatly improves the reliability of the system. Finally, the system is restored to its initial state, laying the foundation for subsequent precise pressure control.

[0053] When the vacuum regulating valve is powered on, the technical solution of the present application first controls the valve plate to rotate at a specified speed through a stepper driver. This step utilizes the aforementioned valve speed model to accurately control the speed of the valve plate, avoiding the position error caused by the excessive start-up speed in the traditional method. For example, the initial speed can be set to 60rpm, and then gradually increased to 200rpm according to the valve speed model.

[0054] Next, the system will detect the valve plate blocking in real time. This can be achieved by monitoring the two-phase current difference of the stepper driver. When the two-phase current difference is detected to increase suddenly, for example, exceeding 0.5A, the system will determine that the valve plate is blocked and immediately control the valve plate to stop rotating. This mechanism effectively prevents mechanical damage that may be caused by forced rotation of the valve plate.

[0055] After detecting a stall and stopping, the system will use the valve speed model to control the stepper driver to drive the valve plate to reverse at a specified speed according to the preset number of steps. The preset number of steps here can be set according to actual conditions, for example, 500 steps. During the reversal process, the system will dynamically adjust the speed according to the valve speed model to ensure the smoothness and accuracy of the reversal process.

[0056] Finally, after the valve plate stops rotating, the system will restore the vacuum regulating valve pressure control system to its initial state. This includes clearing the encoder registers and position data on the MCU, clearing any error flags, and setting the system parameters to the predetermined initial values. This step prevents the errors generated by each control from being accumulated, ensuring that the system can start working from a known and stable state every time it is powered on.

[0057] Through this series of steps, the technical solution of the present application effectively solves the problem of precise control and initialization of the vacuum regulating valve when it is powered on. By restoring the system to a known initial state, the present solution ensures that the system is in a predictable and controllable state after each startup. This greatly improves the stability and reliability of the system and reduces the control error caused by the uncertainty of the initial state.

[0058] In some embodiments, the specific steps in step A2 include: A21. Check the valve plate blocking condition according to the following steps: A211. Get the two-phase current difference of the stepper driver; A212. When the current difference between the two phases increases, it is determined that the valve plate is blocked and the valve plate is controlled to stop rotating.

[0059] In actual application, an obstacle is installed on the transmission shaft between the stepper drive and the valve plate to block the return to zero position, so that the valve plate will be stuck when it rotates. When the stall occurs, it means that the valve plate has reached a predetermined position. Thereafter, in combination with the steps of the above embodiment, the valve plate is controlled to reverse according to a predetermined number of steps based on this position. Compared with controlling the valve plate to rotate directly to the preset return to zero position, the actual position of the valve plate may have an error with the return to zero position, and this error is often greater than the error of the stepper drive controlling the movement of the valve plate according to the predetermined number of steps. Therefore, the stall is used as a signal to reverse the valve plate by a certain number of steps, so that the valve plate can return to zero more accurately (not rotate to the return to zero position, but a certain number of steps away from the return to zero position, which is equivalent to returning to zero).

[0060] The present embodiment detects the blocking of the valve plate by monitoring the two-phase current difference of the stepper driver. When the valve plate is operating normally, the two-phase current difference of the stepper driver should be maintained within a relatively stable range. If the valve plate encounters an obstacle or is hindered by other external forces, the motor needs to increase the output torque to overcome these resistances, which will cause the two-phase current difference to increase. By monitoring the changes in the two-phase current difference in real time, the system can quickly detect whether the valve plate is blocked. Once an increase in the two-phase current difference is detected, the system immediately determines that the valve plate is blocked and quickly controls the valve plate to stop rotating. This method can respond in the early stages of valve plate obstruction and effectively prevent the valve plate from being damaged due to continuous force.

[0061] In specific implementation, obtaining the two-phase current difference of the stepper driver can be achieved in many ways. One method is to use a current sensor to directly measure the two-phase current of the stepper driver and then calculate the difference. Another method is to indirectly calculate the current difference by measuring the output voltage of the motor driver. In addition, the current difference can also be estimated by monitoring the back electromotive force of the stepper driver.

[0062] The criteria for judging the increase of the two-phase current difference can be set according to the specific application scenario. For example, a fixed threshold can be set, and when the current difference exceeds this threshold, it is judged to be increased. A dynamic threshold can also be used to dynamically adjust the judgment criteria based on the historical data of the motor operation. More complex algorithms may consider the rate of change of the current difference to more accurately determine whether the valve plate is blocked.

[0063] In practical applications, the implementation process of this method is as follows: First, the system controls the valve plate to rotate at a specified speed through a stepper driver. During the rotation process, the system continuously monitors the two-phase current of the stepper driver. Assume that the two-phase current difference during normal operation is 0.1A, and the threshold set by the system is 0.3A. When the valve plate encounters an obstacle, the motor needs to increase the torque, causing the two-phase current difference to rise rapidly to 0.4A. The system detects this change, immediately determines that the valve plate is blocked, and issues a stop command within 10 milliseconds to control the valve plate to stop rotating. This process only takes tens of milliseconds from detection to reaction, effectively preventing damage to the valve plate and motor.

[0064] This current difference-based detection method has several advantages over the traditional mechanical sensor method. First, it does not require additional mechanical components, reducing system complexity and potential failure points. Second, the current detection response speed is very fast, and it can react when the valve plate encounters slight resistance, greatly improving the timeliness of protection. In addition, the sensitivity of this method can be adjusted through software to adapt to different working environments and requirements, and it has high flexibility.

[0065] In some embodiments, the steps of setting the initial state of the vacuum regulating valve pressure control system include: B1. The control valve plate rotates at a specified speed to close the vacuum regulating valve; B2. Use the valve speed model to control the valve plate to rotate 90° at a specified speed and record the cavity pressure of the vacuum chamber corresponding to the valve plate at different angles to obtain a data table of the angle position of the valve plate and the cavity pressure of the vacuum chamber; B3. Control the angle position of the valve plate according to the data sheet to make the vacuum chamber reach the specified chamber pressure.

[0066] In this embodiment, the control valve plate rotates at a specified speed to close the vacuum regulating valve. This step ensures that the system starts from a known starting point. The valve speed model is then used to control the valve plate to rotate 90°, while recording the cavity pressure at different angles in a scanning-like manner. This step establishes the relationship between the angle position of the valve plate and the cavity pressure, forming a data table. This data table provides the basis for subsequent precise control. Finally, based on the obtained data table, the system can accurately control the angle position of the valve plate so that the vacuum cavity reaches the specified cavity pressure.

[0067] Different sampling strategies can be used in the process of controlling the valve plate to rotate 90° using the valve speed model. For example, pressure data can be recorded every 1°, or non-uniform sampling can be used to increase the sampling frequency in areas with large pressure changes. This flexible sampling strategy can improve the accuracy of the data table while optimizing data storage and processing efficiency.

[0068] The establishment of a data table is the core of this technical solution. The data table can be stored in a data structure such as a two-dimensional array or a hash table, with the key being the valve plate angle and the value being the corresponding cavity pressure. This structure facilitates fast search and interpolation calculations. In practical applications, it may be necessary to consider the impact of environmental factors such as temperature and humidity on pressure, so the data table structure can be expanded to add these parameters as additional dimensions.

[0069] When controlling the valve plate angle position according to the data table, an interpolation algorithm can be used to handle the situation where the target pressure is not in the data table. Common interpolation methods include linear interpolation and spline interpolation. The appropriate algorithm can be selected according to the system's accuracy requirements. In addition, an adaptive control algorithm can be introduced to dynamically adjust the valve plate position according to real-time feedback to further improve control accuracy.

[0070] When this technical solution is used in combination with the aforementioned valve speed model, a more efficient initialization process can be achieved. The valve speed model provides the basis for accurate control of valve plate rotation, while the data table established by this solution through actual measurement provides a direct correspondence between the valve plate position and the cavity pressure. This combination not only improves the accuracy of initialization, but also greatly shortens the initialization time, because the system can quickly locate the valve plate position corresponding to the target pressure directly based on the data table without multiple attempts and adjustments.

[0071] In practical applications, the technical solution can be implemented as follows: First, when the system starts, the control valve plate rotates to the fully closed position at a speed of 2 rpm. Then, the valve speed model is used to control the valve plate to slowly open at a speed of 1 rpm, and the cavity pressure is recorded every time it rotates 1° until it rotates 90°. This process usually takes 1.5-2 seconds to complete. The recorded data forms a data table containing 90 data points. Assuming that the target cavity pressure is 50Pa, the system will query the data table and find the two data points closest to 50Pa, for example, 48Pa corresponds to 45°, and 52Pa corresponds to 46°. Through linear interpolation, the system calculates that the angle corresponding to 50Pa is approximately 45.5°. Finally, the system accurately controls the valve plate to rotate to a position of 45.5° to achieve precise control of the cavity pressure.

[0072] This solution establishes a data table through actual measurement, which can accurately reflect the characteristics of a specific system and greatly improve the control accuracy. In addition, this solution establishes a data table through a single scan, and can quickly and accurately locate the target pressure later, significantly improving the system response speed and efficiency. This method not only realizes the system's autonomous learning and achieves the effect of adapting to various operating conditions, but also provides a reliable foundation for subsequent pressure control, effectively improving the overall performance of the vacuum regulating valve pressure control system.

[0073] Reference Figure 2 The present invention provides a vacuum regulating valve pressure control system, including a stepper driver 100 and a vacuum regulating valve 200. The stepper driver 100 is used to obtain a specified speed through a valve speed model, and then control the valve plate of the vacuum regulating valve 200 to rotate to a specified angular position according to the specified speed; the valve speed model is established based on PWM pulse frequency and Simoid function.

[0074] The vacuum regulating valve pressure control system mainly includes two core components: a stepper driver 100 and a vacuum regulating valve 200. The key to the system is to control the rotation of the valve plate through a valve speed model. The function of the stepper driver 100 is to control the valve plate of the vacuum regulating valve 200 to rotate to a specified angle position according to the specified speed obtained by the valve speed model. This precise control can achieve precise regulation of the vacuum chamber pressure. The valve speed model is established based on PWM pulse frequency and Sigmoid function. The PWM pulse frequency can provide precise speed control, while the Sigmoid function can achieve smooth acceleration and deceleration processes, avoid sudden changes during valve plate movement, and thus improve the stability and accuracy of control. In this way, the system can accurately control the rotation speed and angular position of the valve plate, thereby achieving precise regulation of the vacuum chamber pressure. Compared with traditional control methods, this model-based control method can provide higher accuracy, better dynamic response characteristics and higher stability.

[0075] In some embodiments, the vacuum regulating valve pressure control system further includes a return-to-zero controller 300, and the return-to-zero controller 300 is used to perform the following steps when the vacuum regulating valve 200 is powered on: A1. The valve plate is controlled to rotate at a specified speed by the stepping driver 100; A2. Detect the blocking of the valve plate and control the valve plate to stop rotating when the valve plate is detected to be blocked; A3. Using the valve speed model to control the stepper driver 100 to drive the valve plate to reverse at a specified speed according to a preset number of steps; A4. After the valve plate stops rotating, restore the vacuum regulating valve pressure control system to its initial state.

[0076] The zero return controller 300 is the core of the whole zero return process, responsible for controlling and coordinating the execution of each step. It can be implemented by a microcontroller or a programmable logic controller (PLC), and manages the whole zero return process through preset program logic. The zero return controller 300 is connected to the stepper driver 100 and various sensors, receives and processes relevant signals, and makes corresponding control decisions.

[0077] In some embodiments, the return-to-zero controller 300 performs the following when detecting a valve plate jam: A21 detects valve plate blocking according to the following steps: A211 obtains the two-phase current difference of the stepper driver 100; A212. When the current difference between the two phases increases, it is determined that the valve plate is blocked and the valve plate is controlled to stop rotating.

[0078] This technical solution detects the jamming of the valve plate by monitoring the two-phase current difference of the stepper motor. When the valve plate is operating normally, the two-phase current difference of the stepper motor should be maintained within a relatively stable range. If the valve plate is blocked by an obstacle or other reasons, the motor needs to increase the output torque to overcome the resistance, which will cause the two-phase current difference to increase. By monitoring the changes in the two-phase current difference in real time, the system can quickly detect whether the valve plate is blocked. Once an increase in the two-phase current difference is detected, the zero return controller 300 immediately determines that the valve plate is blocked and quickly controls the valve plate to stop rotating. This method can detect problems in a timely manner when the valve plate is just beginning to be blocked, avoiding damage that may be caused by continued forced rotation of the valve plate.

[0079] In some embodiments, the vacuum regulating valve pressure control system further includes an initialization controller 400, and the initialization controller 400 is used to perform the following steps: B1. Using the valve speed model to control the valve plate to rotate at a specified speed to close the vacuum regulating valve 200; B2. Use the valve speed model to control the valve plate to rotate 90° at a specified speed and record the cavity pressure of the vacuum chamber corresponding to the valve plate at different angles to obtain a data table of the angle position of the valve plate and the cavity pressure of the vacuum chamber; B3. Control the angle position of the valve plate according to the data sheet to make the vacuum chamber reach the specified chamber pressure.

[0080] The initialization controller 400 plays a key role in the vacuum regulating valve pressure control system. It establishes the correspondence between the valve plate angle position and the vacuum chamber pressure by executing a series of steps, so that the system has adaptive learning capabilities. The data table is the basis for achieving precise pressure control. The system can adjust the valve plate angle position according to this data table to achieve the specified chamber pressure. This method allows the system to quickly and accurately adjust the valve plate position under different pressure requirements.

[0081] In this document, relational terms such as first and second, etc. are used merely to distinguish one entity or operation from another entity or operation, but do not necessarily require or imply any such actual relationship or order between these entities or operations.

[0082] The above description is only an embodiment of the present invention and is not intended to limit the protection scope of the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A control method for a vacuum regulating valve pressure control system, characterized in that: The method comprises obtaining a specified speed through a valve speed model, and then controlling a valve plate of a vacuum regulating valve to rotate to a specified angle position according to the specified speed; the valve speed model is established based on a PWM pulse frequency and a Simoid function.

2. The control method of the vacuum regulating valve pressure control system according to claim 1, characterized in that: The specific expression of the Simoid function is: ； in, For about Simoid function, is less than integer variable, is the preset number of acceleration times; The specific expression of the valve speed model is: ； in, For about The valve speed model, is the minimum value of PWM pulse frequency, It is the maximum value of PWM pulse frequency.

3. The control method of the vacuum regulating valve pressure control system according to claim 2, characterized in that: Obtaining the specified speed through the valve speed model includes calculating the specified speed according to the following formula: ； in, is the specified speed, are preset parameters.

4. The control method of the vacuum regulating valve pressure control system according to claim 1, characterized in that: When the vacuum regulating valve is powered on, the following steps are performed: A1. Controlling the valve plate to rotate at the specified speed through a stepper driver; A2. Detect the blocking of the valve plate and control the valve plate to stop rotating when the valve plate is detected to be blocked; A3. Using the valve speed model to control the stepper driver according to a preset number of steps to drive the valve plate to reverse at the specified speed; A4. After the valve plate stops rotating, the vacuum regulating valve pressure control system is restored to an initial state.

5. The control method of the vacuum regulating valve pressure control system according to claim 4, characterized in that: The specific steps in step A2 include: A21. Detect the blocking condition of the valve plate according to the following steps: A211 obtains the two-phase current difference of the stepper driver; A212. When the two-phase current difference increases, it is determined that the valve plate is blocked and the valve plate is controlled to stop rotating.

6. The control method of the vacuum regulating valve pressure control system according to claim 4, characterized in that: The steps of setting the initial state of the vacuum regulating valve pressure control system include: B1. Controlling the valve plate to rotate at the specified speed so that the vacuum regulating valve is closed; B2. Using the valve speed model to control the valve plate to rotate 90° at the specified speed and record the cavity pressure of the vacuum chamber corresponding to the valve plate at different angular positions, to obtain a data table of the angular position of the valve plate and the cavity pressure of the vacuum chamber; B3. Control the angular position of the valve plate according to the data table so that the vacuum chamber reaches a specified chamber pressure.

7. A vacuum regulating valve pressure control system, characterized in that: It includes a stepper driver and a vacuum regulating valve. The stepper driver is used to obtain a specified speed through a valve speed model, and then control the valve plate of the vacuum regulating valve to rotate to a specified angle position according to the specified speed; the valve speed model is established based on PWM pulse frequency and Simoid function.

8. The vacuum regulating valve pressure control system according to claim 7, characterized in that: It also includes a return-to-zero controller, which is used to perform the following steps when the vacuum regulating valve is powered on: A1. Controlling the valve plate to rotate at the specified speed through a stepper driver; A2. Detect the blocking of the valve plate and control the valve plate to stop rotating when the valve plate is detected to be blocked; A3. Using the valve speed model to control the stepper driver according to a preset number of steps to drive the valve plate to reverse at the specified speed; A4. After the valve plate stops rotating, the vacuum regulating valve pressure control system is restored to an initial state.

9. The vacuum regulating valve pressure control system according to claim 8, characterized in that: The return-to-zero controller performs the following when used to detect the blocking condition of the valve plate: A21. Detect the blocking condition of the valve plate according to the following steps: A211 obtains the two-phase current difference of the stepper driver; A212. When the two-phase current difference increases, it is determined that the valve plate is blocked and the valve plate is controlled to stop rotating.

10. The vacuum regulating valve pressure control system according to claim 7, characterized in that: The initialization controller is used to perform the following steps: B1. Using the valve speed model to control the valve plate to rotate at the specified speed to close the vacuum regulating valve; B2. Using the valve speed model to control the valve plate to rotate 90° at the specified speed and record the cavity pressure of the vacuum chamber corresponding to the valve plate at different angular positions, to obtain a data table of the angular position of the valve plate and the cavity pressure of the vacuum chamber; B3. Control the angular position of the valve plate according to the data table so that the vacuum chamber reaches a specified chamber pressure.

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