Valve plate control method, device and storage medium for vacuum butterfly valve

Abstract

The valve plate control method, device, and storage medium for the vacuum butterfly valve proposed in this application acquire the back electromotive force signal generated internally by the motor when driving the valve plate to rotate, and the driving parameters at the current moment; based on the back electromotive force signal and driving parameters, the reference position and speed of the motor are estimated using a preset motion state estimation logic; based on the reference position and speed estimation, the driving control quantity of the motor is calculated using a preset dual closed-loop control logic; an S-curve acceleration / deceleration planning algorithm is used to perform secondary processing on the speed command quantity to generate a speed control curve containing multiple stages, and the driving control quantity is adjusted based on the speed control curve; the valve plate of the motor is controlled to complete the opening and closing operation based on the driving control quantity. This invention does not require an external position sensor, and by setting a dual closed-loop control logic for position and speed, it achieves fast, smooth, and overshoot-free opening and closing of the valve plate throughout its entire stroke, while reducing the risk of step loss and vacuum disturbance.

Description

Technical Field

[0001] This application relates to the field of valve control technology for semiconductor process equipment, and in particular to a valve plate control method, device and storage medium for a vacuum butterfly valve. Background Technology

[0002] Vacuum butterfly valves are widely used in semiconductor equipment, vacuum coating equipment, vacuum pump systems, and vacuum transmission systems to achieve vacuum chamber isolation, gas path switching, and vacuum level regulation.

[0003] Existing vacuum butterfly valves typically employ stepper motor open-loop control, encoder closed-loop control, or servo control to achieve valve plate opening and closing. Furthermore, current methods for controlling valve plate opening and closing primarily utilize simple position pulse planning or single-loop speed regulation, which cannot simultaneously achieve rapid response, low vibration, and high stability, resulting in vibration, noise, and mechanical shock during valve plate movement. Summary of the Invention

[0004] In view of this, this application proposes a valve plate control method, device and storage medium for a vacuum butterfly valve to solve the problem that the valve plate control of existing vacuum butterfly valves cannot simultaneously achieve rapid response and smooth control of valve plate opening and closing.

[0005] In a first aspect, embodiments of this application provide a valve plate control method for a vacuum butterfly valve, applied to a valve opening control system, wherein the valve opening control system includes at least a motor connected to the valve plate, and the method includes: Obtain the back electromotive force signal generated inside the motor when it drives the valve plate to rotate and the driving parameters at the current moment; Based on the back electromotive force signal and the driving parameters, the reference position and speed of the motor are estimated using a preset motion state estimation logic. Based on the reference position and the estimated speed, the drive control quantity of the motor is calculated through a preset dual closed-loop control logic, wherein the preset dual closed-loop control logic includes a position loop control logic as the outer loop and a speed control loop logic as the inner loop. An S-curve acceleration / deceleration planning algorithm is used to perform secondary processing on the speed command quantity to generate a speed control curve containing multiple stages, and the drive control quantity is adjusted based on the speed control curve. The motor's valve plate is controlled to perform opening and closing operations based on the drive control quantity.

[0006] Secondly, embodiments of this application provide a vacuum butterfly valve device, including a processor and a memory. The memory stores machine-executable instructions that can be executed by the processor. The processor executes the machine-executable instructions to implement the valve plate control method of the vacuum butterfly valve described above.

[0007] Thirdly, embodiments of this application provide a computer-readable storage medium storing computer-executable instructions. When the computer-executable instructions are called and executed by a processor, the computer-executable instructions cause the processor to implement the above-described valve plate control method for a vacuum butterfly valve.

[0008] The embodiments of this application bring the following beneficial effects: The aforementioned vacuum butterfly valve control method, device, and storage medium acquire the back electromotive force signal generated internally by the motor when driving the valve plate to rotate, and the current driving parameters. Based on the back electromotive force signal and the driving parameters, a preset motion state estimation logic is used to estimate the reference position and speed of the motor. Based on the reference position and speed estimation, a preset dual-closed-loop control logic is used to calculate the driving control quantity of the motor, and the valve plate is controlled to complete the opening and closing operation based on the driving control quantity. The preset dual-closed-loop control logic includes a position loop control logic as the outer loop and a speed control loop logic as the inner loop. This application utilizes the estimated speed to drive the valve plate to complete the opening and closing operation through the preset closed-loop control logic, achieving real-time perception and closed-loop control of the valve plate's motion state throughout its entire stroke. This effectively suppresses load disturbances, reduces the risk of step loss, and improves the valve plate's positioning accuracy and operational reliability. Meanwhile, by introducing strategies such as S-curve acceleration and deceleration planning, speed limiting, integral limiting, and feedforward compensation, the mechanical shock and vibration during the valve plate opening and closing process can be reduced, the pressure disturbance to the vacuum system can be reduced, and the valve plate can achieve fast, smooth, and overshoot-free opening and closing action.

[0009] Other features and advantages of this application will be set forth in the following description and will be apparent in part from the description or may be learned by practicing the application. The objectives and other advantages of this application are realized and obtained through the structures particularly pointed out in the description, claims and drawings.

[0010] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0011] To more clearly illustrate the specific embodiments of this application or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0012] Figure 1 A flowchart of a first embodiment of the valve plate control method for a vacuum butterfly valve provided in this application; Figure 2A flowchart illustrating a second embodiment of the valve plate control method for the vacuum butterfly valve provided in this application. Figure 3 A schematic diagram of the valve opening control system provided in the embodiments of this application; Figure 4 A schematic diagram of acceleration / deceleration planning curves provided in an embodiment of this application; Figure 5 This is a schematic diagram of the structure for obtaining the back electromotive force signal provided in an embodiment of this application; Figure 6 A schematic diagram of a first structure of a valve plate control device for a vacuum butterfly valve provided in an embodiment of this application; Figure 7 A second structural schematic diagram of the valve plate control device for the vacuum butterfly valve provided in the embodiments of this application; Figure 8 This is a schematic diagram of a vacuum butterfly valve device provided in an embodiment of this application. Detailed Implementation

[0013] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0014] The terms “first,” “second,” “third,” “fourth,” etc. (if present) in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a particular order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments described herein can be implemented in a sequence other than that illustrated or described herein. Furthermore, the terms “comprising” or “having,” and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0015] In semiconductor processing applications, vacuum butterfly valves are mainly used for vacuum chamber isolation, vacuum regulation, and gas path switching. Currently, the opening and closing action of the valve plate in vacuum butterfly valves is typically driven by a stepper motor, servo motor, or DC motor, which rotates the valve stem through a reduction gear to achieve the opening and closing of the valve plate. However, regardless of the driving method used, there is a problem of low control accuracy, especially during the control process when the motor is starting up or at low speed. Current control principles cannot achieve this, and even if they can, the control accuracy is extremely poor.

[0016] To address this issue, this application proposes a precision motion control method that eliminates the need for an external encoder, reliably senses the valve plate status during low-speed and startup phases, and achieves dual closed-loop control of position and speed. Specifically, it detects the back electromotive force (EMF) of the motor windings, then selects the corresponding estimation logic based on the specific value of the back EMF to estimate the motor's control input. Furthermore, when controlling the valve plate's movement based on the control input, a dual closed-loop control logic is introduced, thereby solving problems such as startup blind zone, low-speed blind zone, high risk of step loss, insufficient control accuracy, and complex structure in existing technologies.

[0017] For ease of understanding, the specific process of the embodiments of this application is described below. Figure 1 A schematic diagram of the valve plate control method for a vacuum butterfly valve is shown. Figure 1 As shown, this application provides a valve plate control method for a vacuum butterfly valve, applied to a valve opening control system. This valve opening control system includes at least a motor connected to the valve plate. The method includes: Step S110: Obtain the back electromotive force signal generated inside the motor when it drives the valve plate to rotate.

[0018] It should be noted that the motor can be a servo motor, stepper motor, or other controllable rotation motor. The back electromotive force (EMF) signal refers to the induced voltage signal generated when the motor's windings cut magnetic lines of force during operation, which is opposite in direction to the driving voltage. In this application, this signal is generated by the motor's detection winding or non-driving phase winding, and is used to indirectly reflect the motor's actual speed and rotor position; wherein the detection winding can be one or more sets of coils located inside the motor specifically for inducing back EMF, independent of the driving winding, and used to provide feedback signals reflecting the motor's motion state.

[0019] In one embodiment, step S110 can be achieved by acquiring an induced voltage signal and then converting it into a back electromotive force signal. Specifically, the induced voltage signal generated by the detection winding of the motor is acquired when the motor drives the valve plate to rotate; the induced voltage signal is modulated to obtain the corresponding back electromotive force signal.

[0020] In practical applications, data acquisition is achieved by configuring a unit with a generator coil, either inside or outside the motor. When installed inside the motor, a detection winding can be placed inside the motor to form the physical source of the signal acquisition. When installed outside the motor, a magnetic field plus a detection winding is required.

[0021] After acquiring the induced voltage signal, it typically contains a fundamental component proportional to the motor speed, as well as a large amount of switching noise and harmonics. Therefore, modulation processing of the induced voltage signal is necessary to effectively suppress noise and extract a back electromotive force (EMF) signal that accurately reflects the motor speed and rotor phase. The signal acquired in this way transforms the original analog signal, which contains a lot of interference, into a stable and effective back EMF signal that can be used for subsequent digital processing, providing a reliable first-hand data source for the entire control chain.

[0022] As a specific implementation, the above-mentioned modulation processing of the induced voltage signal to obtain the corresponding back electromotive force signal includes: inputting the induced voltage signal into an integral filter circuit, introducing a bias voltage and reset control logic, performing filtering and calibration processing on the induced voltage signal to obtain a calibration voltage signal; performing amplitude clamping protection processing on the calibration voltage signal and then performing analog-to-digital conversion sampling to obtain the corresponding back electromotive force signal.

[0023] Specifically, the integrating filter circuit here essentially performs low-pass filtering and noise smoothing of the signal. It effectively filters out the high-frequency noise from PWM chopping commonly found in stepper motor drivers, extracting the low-frequency effective component of the back electromotive force. Simultaneously, the introduced bias voltage is used to raise or lower the signal zero point to match the input range of the subsequent analog-to-digital converter circuit and compensate for the circuit's own drift. The reset control logic prevents saturation drift of the integrator after prolonged operation, ensuring the consistency and stability of the extracted signal. The calibration voltage signal obtained by the integrating filter circuit is then subjected to amplitude clamping protection to prevent abnormal high voltage from damaging the analog-to-digital converter. This multi-level modulation processing ensures that the finally acquired back electromotive force signal has an extremely high signal-to-noise ratio and high reliability.

[0024] Step S120: Determine whether the motor meets the preset low-speed condition based on the back electromotive force signal, and obtain the judgment result.

[0025] It should be noted that "low speed" should be understood as the motor rotating within a specific low speed range, the motor starting stage, or the valve plate of the vacuum butterfly valve approaching the target opening position at a specific low speed.

[0026] The preset low-speed condition is pre-set based on the motor parameters and usage status. It is mainly used as a logical condition to determine that the motor is in a low-speed or stationary state where the back electromotive force signal is insufficient for reliable estimation. Specifically, the judgment is based on the magnitude of the back electromotive force signal.

[0027] The implementation of step S120 is specifically achieved by determining whether the effective voltage of the back electromotive force signal is greater than the voltage threshold set in the low-speed state. If it is, the preset low-speed condition is met; otherwise, it is not.

[0028] In this embodiment, the step of determining whether the motor meets the preset low-speed condition based on the back EMF signal and obtaining the determination result includes: extracting the corresponding back EMF feature quantity from the back EMF signal and determining whether the back EMF feature quantity is greater than a preset validity threshold; if the back EMF feature quantity is not greater than the preset validity threshold, then the motor is determined to be in a low-speed operating state; if the back EMF feature quantity is greater than the preset validity threshold, then the motor is determined to be in a normal operating state.

[0029] In other words, this back EMF characteristic is a feature value that can describe the signal strength, such as the signal amplitude, RMS value, or filtered DC component. The preset validity threshold is a dividing line, set based on experimental or calibration data, defining the minimum signal strength at which the back EMF mode can reliably operate. Through this explicit threshold comparison, it is possible to clearly distinguish between a low-speed operating state requiring special handling and a normal operating state that can rely on back EMF, thus providing a clear and quantitative basis for subsequent mode estimation decisions.

[0030] In one embodiment, the above-mentioned determination of whether the back electromotive force characteristic quantity is greater than a preset validity threshold includes: calculating the absolute value of the difference between the back electromotive force characteristic quantity and the zero-point bias of the back electromotive force of the valve plate in a static state; and determining whether the absolute value is greater than the preset validity threshold. The calculation formula is as follows: , It is a characteristic quantity of back electromotive force. The zero-point bias value of the back electromotive force of the valve plate in a static state. This is the effective threshold for back electromotive force.

[0031] This method provides a more accurate judgment by eliminating the influence of zero-point bias. The back EMF signal may not be strictly zero when the motor is completely stationary, and there may be... This circuit bias is used. By calculating the absolute value of the difference, the algorithm can accurately extract the effective signal components truly generated by the motor rotation, and then compare them with the effectiveness threshold. Comparison. This method eliminates judgment errors caused by factors such as temperature drift of electronic components, and improves the accuracy of low-speed state identification.

[0032] Step S130: Based on the target state estimation mode corresponding to the judgment result, and based on the estimation logic corresponding to the target state estimation mode, estimate the motion state of the motor. The motion state estimation includes at least the speed estimation.

[0033] The motion state estimation quantity refers to a physical quantity characterizing the current motion state of the motor, calculated through a physical or mathematical model. It includes at least a speed estimation quantity and may further include a position estimation quantity. The speed estimation quantity is an estimate of the motor's current actual speed. It serves as the basis for closed-loop control and can be calculated from the back electromotive force signal or predicted by a model under low-speed conditions.

[0034] In one embodiment, the above-mentioned estimation of the motor's motion state based on the target state estimation mode corresponding to the judgment result and the estimation logic corresponding to the target state estimation mode includes two processing scenarios: In the first scenario, if the judgment result indicates a low-speed operation, the corresponding target state estimation mode is determined to be the model prediction estimation mode. Based on the motor's control parameters and a preset startup phase model, the first estimated speed of the motor is calculated. The model prediction estimation mode refers to an estimation mode that predicts the current motion state of the motor based on its control parameters (such as input pulses, cumulative angles, etc.) and a preset mathematical model when the back EMF signal cannot be effectively used due to the low motor speed.

[0035] At low speeds, the back EMF signal is weak or even unusable, at which point the system relies entirely on the motor's control parameters and the startup phase model. These control parameters are commands issued by the controller itself, unaffected by load disturbance noise, and provide a stable, noise-free reference prediction. The first speed estimate fills the gap in back EMF during startup and low-speed ranges, ensuring continuous and usable speed feedback for the closed-loop controller across the entire speed domain, achieving complete coverage of the low-speed and startup blind zones.

[0036] Specifically, the reference speed ω is predicted based on the motor input pulses, accumulated micro-step angles, and acceleration / deceleration planning. ref With reference position θ ref .

[0037] In the second scenario, if the judgment result indicates normal operation, the corresponding target state estimation mode is determined to be the back EMF estimation mode. Based on the back EMF characteristic quantity and the pre-established calibration compensation and mathematical model, the second speed estimate of the motor is calculated. The back EMF estimation mode refers to an estimation mode that calculates the current motion state of the motor by using the back EMF signal and combining it with the motor's mathematical model when the motor speed reaches a certain level and the back EMF signal is sufficiently stable and reliable.

[0038] Once the motor is in normal operation, the back EMF signal already possesses sufficient signal-to-noise ratio and reliability. At this point, the back EMF estimation mode can directly and in real-time reflect the motor's actual speed, with accuracy and dynamic response superior to model predictions. Pre-established calibration compensation and mathematical models have calibrated parameter differences between individual motors and under different temperature environments, ensuring a high degree of consistency in the second speed estimate calculated based on back EMF characteristic quantities.

[0039] The calibration compensation and mathematical model are actually trained and constructed through pre-calibration. Specifically, the zero-point offset of the back EMF of the valve plate in a static state and the characteristic back EMF of the motor at each calibrated speed are collected. A relationship curve is plotted based on each calibrated speed and the characteristic back EMF, and this curve is fitted and temperature compensation is applied to obtain the calibration compensation and mathematical model of back EMF and speed. By collecting the zero-point offset in a static state and the characteristic back EMF at multiple known calibrated speeds, an original "speed-back EMF" relationship curve can be plotted. Due to manufacturing tolerances, the curve is different for each motor. Through mathematical fitting (such as linear or polynomial fitting), the curve can be transformed into a specific mathematical formula. This "personalized" calibration compensation and mathematical model is called every time back EMF estimation is performed subsequently to eliminate inconsistencies caused by individual motor differences.

[0040] In practical applications, due to differences in the number of winding turns, magnet strength, assembly eccentricity, and temperature drift among different motors, direct control using back electromotive force will produce errors. Therefore, when establishing calibration compensation and mathematical models, a calibration compensation mechanism is introduced. The specific implementation process includes: S1: Static zero-point calibration.

[0041] This step mainly involves calibrating the valve plate in a static state, by collecting data at the calibration points. As a zero-point offset.

[0042] S2: Multi-speed point calibration.

[0043] It should be noted that the speed point refers to the rotor speed point in the motor, that is, setting multiple speed acquisition points, driving the motor at several known speeds (e.g., ω1, ω2, ω3), and collecting the back electromotive force characteristic quantity. Then, based on the collected data, establish The mapping relationship with ω.

[0044] S3: Fitting modeling.

[0045] Two methods were used to build the model: The first method uses a linear or piecewise linear model to fit the model, and the corresponding formula for the model is as follows: ,in, This is the actual speed of the motor. It is a characteristic quantity of back electromotive force. The zero-point bias value of the back electromotive force of the valve plate in a static state, where a and b are constants, and b Stored in the controller.

[0046] The second method uses polynomial fitting to construct the model, and the corresponding formula for the model is as follows: ,in, denoted as the fitting coefficients of the i-th order polynomial, where i is the polynomial order index and n is the highest order of the polynomial.

[0047] S4: Temperature compensation.

[0048] This step involves constructing the model based on steps S1-S3. Since temperature affects the back electromotive force, temperature compensation is added to the model. Specifically, the driver temperature T or motor temperature T is collected and adjusted accordingly. : ,in, This is the back electromotive force coefficient after temperature compensation. The back electromotive force coefficient at the reference temperature, This is the temperature compensation coefficient at temperature T. To determine the reference temperature.

[0049] In one embodiment, for the model prediction estimation mode under low-speed operation, the above-mentioned estimation of the first speed of the motor based on the motor control parameters and the preset start-up stage model includes: acquiring the motor input pulse, microstep angle accumulation and acceleration / deceleration planning, and inputting them into the preset start-up stage model to estimate the first speed of the motor.

[0050] It should be noted that the input pulse, cumulative microstep angle, and acceleration / deceleration planning control parameters are all instructions actively issued by the driver that controls the motor operation. These parameters are known in the controller and are free from interference.

[0051] The pre-defined startup phase model is actually a set of equations based on motor kinematics or dynamics, which can translate these commands into predictions of the current speed. This process is completed entirely in the digital domain and does not rely on any analog signals, making it particularly suitable for operating conditions where signals are missing, such as startup and extremely low speeds.

[0052] Furthermore, in order to improve the accuracy of model prediction and estimation, especially to compensate for prediction deviations caused by load disturbances, the above-mentioned model estimation of the first speed of the motor based on the motor control parameters and the preset start-up stage also includes: injecting a disturbance current of preset amplitude into the detection winding of the motor and collecting the current response change parameters of the detection winding after the disturbance; estimating the load state estimate and the rotor hysteresis trend estimate of the motor based on the current response change parameters; and correcting the first speed estimate based on the load state estimate and the rotor hysteresis trend estimate.

[0053] In the low-speed phase, by actively injecting a known, small disturbance current into the sensing winding and observing the resulting changes in current response parameters (such as the rate of change of current), the motor's load state and the rotor's actual following ability can be indirectly detected. If the load is heavy, the rotor's lag will be more pronounced, and the response parameters will also change. Through this correction, the initial speed estimate is no longer a purely open-loop prediction but incorporates the perception of the actual physical load, further improving the control accuracy and disturbance rejection capability in the low-speed phase.

[0054] In one embodiment, after estimating the motor's motion state based on the target state estimation mode corresponding to the judgment result and the estimation logic corresponding to the target state estimation mode, the method further includes: determining the corresponding fusion weight based on the motor's motion state estimation, and performing fusion calculation on the first speed estimation and the second speed estimation based on a preset weighted fusion algorithm to obtain the final speed estimation.

[0055] To ensure a smooth transition from the low-speed prediction mode to the high-speed back-EMF mode, a soft fusion strategy is employed instead of a hard switch. The fusion weights are determined based on the motion state estimation (e.g., the current speed level). For example, in the low-speed range, the first speed estimate from the model prediction has a dominant weight; as the speed increases, the weight of the second speed estimate from the back-EMF gradually increases. Through weighted fusion, a smooth and seamless switch between the two estimation modes is achieved, avoiding control command jumps caused by sudden changes in the estimation source and ensuring the smoothness of the valve plate movement.

[0056] Specifically, the aforementioned pre-defined weighted fusion algorithm is as follows: ,in, This is the estimated value for the second rotational speed. This is the estimated value for the first rotational speed. The fusion weighting coefficient increases in value as the motor speed increases.

[0057] The above fusion calculation formula provides a specific calculation method for first-order linear fusion, including the weighting coefficients. It is a variable that varies between 0 and 1, and it is positively correlated with the motor speed. When the motor speed is very low, Approaching 0, It mainly depends on the model's prediction and estimation. When the engine speed enters the high-speed range, Approaching 1, It is mainly estimated by back electromotive force. The decision is made. This continuously changing weighting mechanism ensures the continuity and smoothness of the velocity feedback signal.

[0058] In one embodiment, for the back EMF estimation mode under normal operating conditions, the above-mentioned estimation of the second motor speed based on the back EMF characteristic quantity and a pre-established calibration compensation and mathematical model includes: obtaining the current operating temperature of the motor, and calculating the back EMF compensation coefficient based on the operating temperature and temperature compensation strategy; inputting the back EMF compensation coefficient and the back EMF characteristic quantity into the pre-established calibration compensation and mathematical model for estimation to obtain the second speed estimate. Changes in the motor's operating temperature will alter the characteristics of the internal magnetic materials, thereby affecting the back EMF coefficient. If the temperature effect is ignored, the speed estimation will introduce a large error. This embodiment introduces a temperature compensation strategy linked to the operating temperature to calculate the back EMF compensation coefficient to correct the mathematical model, ensuring that the second speed estimate maintains high accuracy even when the temperature changes due to long-term operation of the equipment, thus improving the long-term stability and environmental adaptability of the system.

[0059] Step S140: Based on the estimated rotational speed, the valve plate of the motor is driven to complete the opening and closing operation through the preset closed-loop control logic.

[0060] In this step, the number of cumulative input pulses of the motor at the current moment is collected, and the corresponding reference position is calculated based on the number; the estimated speed is integrated to obtain the estimated position; based on the reference position and the estimated position, the drive control quantity of the motor is calculated through a preset dual closed-loop control logic, and the valve plate of the motor is controlled to complete the opening and closing operation based on the drive control quantity.

[0061] Specifically, when controlling the opening and closing of the control valve plate, it is actually controlled by controlling the opening and closing position of the control valve plate, which is first obtained from the reference position Pcmd obtained by accumulating control pulses; The estimated position Pest is obtained by integrating the actual velocity estimated from the back electromotive force.

[0062] Location estimation formula: ,in, Estimate the quantity for the current position. This is the estimated position at the previous sampling time. This is an estimate of the current rotational speed. To control the sampling period, This represents the current discrete sampling time.

[0063] Furthermore, the reduction ratio and valve stem transmission ratio are converted into valve plate angle or valve plate opening percentage. At the same time, the valve mechanical limits (mechanical limit, stroke end point) can be combined for boundary correction to improve the estimation stability. Finally, the position is gradually controlled based on the estimated parameters until the target position is reached.

[0064] The valve plate control method for vacuum butterfly valves provided in the above embodiments acquires the back electromotive force signal generated by the motor during the rotation of the valve plate, and determines whether the motor meets the preset low-speed conditions based on the back electromotive force signal. Then, based on the determination result, the corresponding target state estimation mode is selected to estimate the motor motion state. On this basis, the speed estimation is used to construct a dual closed-loop control logic to drive the valve plate to complete the opening and closing operation. Thus, real-time perception and closed-loop control of the valve plate motion state can be achieved without configuring an external encoder. This solves the problem that the valve plate control of existing vacuum butterfly valves cannot cover the start-up stage and low-speed stage, and the opening and closing control accuracy is low. At the same time, it can also effectively perceive the actual operating state of the motor, reduce the risk of loss of synchronization caused by load disturbance, and improve the valve plate positioning accuracy and operational reliability.

[0065] like Figure 2 and 3 As shown in the embodiments of this application, another valve plate control method for a vacuum butterfly valve is also provided, which is applied to a valve opening control system, such as... Figure 3 As shown, the valve opening control system includes: a stepper motor drive module, a detection winding / feedback winding module, a signal conditioning module, an actuator module, a power supply and protection module, and an induction coil, wherein the stepper motor drive module is connected to the motor driving the valve plate.

[0066] The stepper motor drive module is used to drive the windings of a two-phase stepper motor and supports constant current control and micro-step drive. The detection winding / feedback winding module is used to acquire the induced voltage signal generated by the motor movement, and this module is installed inside the motor; The signal conditioning module includes a high-impedance input, integral filtering, bias voltage generation, and clamping protection circuit, which converts the detection signal into an analog quantity suitable for MCU sampling. The MCU control module is used for ADC sampling, back EMF signal calculation, state estimation, closed-loop PID calculation, and motion planning. The actuator module includes a reduction mechanism, a valve stem, and a limiting structure, which are used to connect to the valve plate of the vacuum butterfly valve; The power supply and protection module provides power to the driver and operational amplifier and provides overcurrent and overvoltage protection.

[0067] The signal conditioning module preferably adopts an integrating operational amplifier structure to filter and integrate the output signal of the detection winding, suppress PWM switching noise and extract stable back electromotive force characteristics, while achieving zero-point calibration and low-speed drift compensation through bias voltage.

[0068] Based on the above system framework, such as Figure 2 As shown, the valve plate control method of the vacuum butterfly valve in this embodiment specifically includes the following steps: Step S210: Obtain the back electromotive force signal generated inside the motor when driving the valve plate to rotate and the driving parameters at the current moment.

[0069] In this embodiment, when acquiring the back electromotive force signal, the induced voltage signal generated by the detection winding of the motor is acquired when the motor drives the valve plate to rotate; the induced voltage signal is modulated to obtain the corresponding back electromotive force signal.

[0070] Obtaining the driving parameters at the current moment actually involves acquiring the control parameters of the motor, including motor input pulses, microstep angle accumulation, and acceleration / deceleration planning.

[0071] In one embodiment, the back electromotive force signal is obtained based on the modulation of the detection winding response, such as... Figure 3 As shown, after the induced voltage signal is collected by the induction coil L, it is transmitted to the operational amplifier for modulation processing, and finally outputs the back electromotive force signal.

[0072] During data acquisition, the induced voltage generated by the detection winding satisfies: ,in, The back electromotive force coefficient, For rotational speed, It is a periodic function related to the rotor electrical angle (which can be approximated as sine / cosine). The rotor electrical angle.

[0073] The detection winding signal enters the integral filter circuit through a high-impedance input resistor. The integral filter circuit sequentially suppresses the high-frequency ripple caused by PWM chopping, extracts the low-frequency effective component of the back electromotive force signal, and avoids integral drift through bias voltage and reset control.

[0074] The output of the integral filter is clamped and protected before being input into the MCU ADC channel to form a digitized back electromotive force signal.

[0075] Step S220: Based on the back EMF signal and drive parameters, the reference position and speed of the motor are estimated using a preset motion state estimation logic.

[0076] In this embodiment, the back EMF signal is determined to meet a preset validity condition. If it does not meet the condition, the first estimated speed and reference position of the motor are estimated based on the input pulse, cumulative microstep angle, and acceleration / deceleration planning in the driving parameters and input into a preset start-up stage model. If the condition is met, the back EMF signal is input into a linear estimation model pre-constructed through calibration compensation to estimate the second estimated speed of the motor. The first estimated speed and the second estimated speed are weighted and fused to obtain the estimated speed of the motor.

[0077] To determine whether the back EMF signal meets the preset validity condition, specifically by setting a back EMF validity threshold. ,when: ,in, It is a characteristic quantity of back electromotive force. The zero-point bias value of the back electromotive force of the valve plate in a static state. This is the effective threshold for back electromotive force.

[0078] In one embodiment, estimating the first speed estimate and reference position of the motor based on the input pulses, cumulative microstep angles, and acceleration / deceleration plans in the driving parameters and inputting them into a preset startup phase model includes: estimating the first speed estimate of the motor by inputting the input pulses, cumulative microstep angles, and acceleration / deceleration plans of the motor into a preset startup phase model; and calculating the corresponding reference position based on the number of cumulative input pulses of the motor at the current moment.

[0079] The back EMF signal is input into a pre-established linear estimation model constructed through calibration and compensation to estimate the second speed estimate of the motor. Specifically, the current operating temperature of the motor is obtained, and the back EMF compensation coefficient is calculated based on the operating temperature and temperature compensation strategy. The back EMF compensation coefficient and the back EMF characteristic quantity are input into the pre-established calibration compensation and mathematical model for estimation to obtain the second speed estimate.

[0080] The step of weighted fusion calculation of the first speed estimate and the second speed estimate to obtain the motor speed estimate includes: determining the corresponding fusion weight based on the motor motion state estimate, and performing a fusion calculation on the first speed estimate and the second speed estimate based on a preset weighted fusion algorithm to obtain the final speed estimate. Specifically, the preset weighted fusion algorithm is as follows: , This is the estimated value for the second rotational speed. This is the estimated value for the first rotational speed. The fusion weighting coefficient increases in value as the motor speed increases.

[0081] Step S230: Based on the reference position and speed estimation, calculate the motor drive control quantity through a preset dual closed-loop control logic, wherein the preset dual closed-loop control logic includes a position loop control logic as the outer loop and a speed control loop logic as the inner loop.

[0082] In this embodiment, an integral operation is first performed based on the estimated rotational speed to obtain the estimated position. Then, based on the reference position and the estimated position, the drive control quantity of the motor is calculated through a preset dual closed-loop control logic, and the motor valve plate is controlled to complete the opening and closing operation based on the drive control quantity.

[0083] Understandably, this step utilizes a complete position-velocity dual closed-loop control system. The reference position is the position the controller expects the motor to reach, calculated from accumulated input pulses, representing the target. The estimated position is obtained by integrating the estimated speed, representing the current actual position. By comparing the two and calculating the drive control quantity through preset dual closed-loop control logic, the valve plate can accurately follow the target position, eliminating the step loss accumulation phenomenon that may occur in open-loop control and achieving a position closed loop without the need for an external encoder.

[0084] In one embodiment, the above-mentioned calculation of the motor drive control quantity based on the reference position quantity and the estimated position quantity through a preset dual-closed-loop control logic includes: generating a speed command quantity through the position loop control logic in the preset dual-closed-loop control logic based on the position deviation between the reference position quantity and the estimated position quantity; and generating the motor drive control quantity through the speed control loop logic in the preset dual-closed-loop control logic based on the speed deviation between the speed command quantity and the speed estimation quantity. This clarifies the hierarchical cooperation relationship within the dual-closed-loop control logic. The outer loop is the position loop control logic, which compares the reference position quantity and the estimated position quantity to generate a speed command quantity as the given target for the inner loop. The inner loop is the speed control loop logic, which compares the speed command quantity with the real-time speed estimation quantity to finally calculate the drive control quantity. The speed loop has a much higher response frequency than the position loop, enabling it to quickly suppress instantaneous speed fluctuations caused by load disturbances, while the position loop ensures that the valve plate is accurately positioned macroscopically. Together, they achieve a balance of speed, stability, and accuracy.

[0085] To generate speed commands using position loop control logic, the position deviation is first calculated, and the calculation formula is as follows: ,in, For positional deviation, For reference position quantity, This is the current estimated location.

[0086] Then, based on the position deviation, the speed command is output, and the output formula is as follows: ,in, The speed command output by the position loop. It is a position loop PID controller, which includes proportional, integral, and derivative terms, and the integral term is limited to prevent integral saturation.

[0087] To generate the motor drive control quantity using the speed control loop logic, the speed deviation is first calculated, and the calculation formula is as follows: ,in, For speed deviation, The target speed.

[0088] Then calculate the drive control quantity. Its calculation formula is , where u is the drive control quantity, and the pulse frequency and acceleration planning are updated based on u.

[0089] Step S240: Using the S-curve acceleration / deceleration planning algorithm, the speed command quantity is processed a second time to generate a speed control curve containing multiple stages, and the drive control quantity is adjusted based on the speed control curve.

[0090] Specifically, based on the travel distance between the current position and the target position, the valve plate movement process is divided into an acceleration phase, a constant speed phase, and a deceleration phase, and a continuously changing speed control curve is generated according to preset acceleration parameters. Specifically, the speed is gradually increased during the acceleration phase, the target operating speed is maintained during the constant speed phase, and the speed is gradually reduced during the deceleration phase as the valve approaches the target position, ensuring a continuous and smooth speed change process.

[0091] Furthermore, the drive control quantity output by the dual closed-loop control logic is adjusted according to the speed control curve to obtain the target drive control quantity. The target drive control quantity includes the drive pulse frequency, drive current amplitude, or corresponding motion control parameters. By adjusting the drive control quantity using a smoothly varying speed control curve, abrupt acceleration changes during the motor-driven valve plate movement can be reduced, mechanical shock and vibration can be decreased, and the valve plate's operational stability can be improved.

[0092] Step S250: The valve plate of the motor is controlled based on the drive control quantity to complete the opening and closing operation.

[0093] In this embodiment, the motor is controlled to run according to the adjusted drive control quantity, and the motor motion is converted into valve plate rotation through the reduction mechanism and valve stem transmission mechanism. Specifically, the drive control quantity is converted into a corresponding valve plate opening control quantity according to the reduction transmission ratio between the motor and the valve plate and the valve stem transmission ratio, thereby driving the valve plate to complete the opening or closing operation according to a predetermined motion trajectory.

[0094] During the valve plate's movement, the dual closed-loop control logic continuously acquires estimated rotational speed and estimated position, and corrects the drive control input in real time, causing the valve plate to gradually approach the target position. Once the valve plate reaches the target position, the controller stops outputting motion commands or maintains the corresponding holding torque to achieve precise positioning control of the valve plate. By combining S-curve acceleration / deceleration planning with dual closed-loop control, the mechanical shock and vibration during the valve plate's opening and closing process can be effectively reduced, achieving rapid, smooth, and non-overshoot-prone opening and closing control of the valve plate.

[0095] In one embodiment, the aforementioned control of the valve plate by the motor based on the drive control quantity to complete the opening and closing operation includes: converting the drive control quantity into corresponding valve plate opening information according to the reduction ratio between the motor and the valve plate and the valve stem transmission ratio, and controlling the valve plate of the motor to complete the opening and closing operation. The drive control quantity is essentially a command to drive the motor, such as the frequency or current amplitude of a stepping pulse. This command acts on the motor and needs to be transmitted through a reducer and valve stem to be finally converted into the actual opening degree of the valve plate. By introducing mechanical parameters such as the reduction ratio and valve stem transmission ratio, the control quantity of the motor can be directly mapped to the control of the valve plate opening degree, allowing the user or upper-level system to operate the valve with intuitive physical quantities such as opening percentage or angle.

[0096] In summary, by using the speed loop as the fast inner loop, load disturbances can be quickly suppressed; while the position loop, as the slow outer loop, ensures the valve plate reaches its final position. When a persistently large speed error is detected, the system automatically reduces acceleration or limits the maximum speed to avoid loss of synchronization.

[0097] In one embodiment, the above-mentioned calculation of the motor drive control quantity based on the reference position quantity and the estimated position quantity through a preset dual closed-loop control logic further includes: using an S-curve acceleration / deceleration programming algorithm to perform secondary processing on the speed command quantity to generate a speed control curve containing multiple stages; and adjusting the drive control quantity based on the speed control curve. The speed command quantity calculated by the position loop control logic may be a step or a rapidly changing signal, and direct execution would cause shock. The S-curve acceleration / deceleration programming algorithm softens the speed command quantity, shaping it into a smooth speed control curve containing multiple stages such as acceleration, constant speed, and deceleration. Adjusting the drive control quantity based on such a smooth curve can greatly reduce the mechanical shock and vibration of the valve plate during start-up, stopping, and speed change processes. Figure 4 As shown, according to the S-curve acceleration and deceleration planning algorithm, a three-stage control strategy is adopted to control the valve plate to the target position. The control stages are acceleration control, constant speed control, and deceleration control. In the acceleration control stage, the acceleration remains constant and the control speed increases with the percentage of the complete stroke. When the stroke reaches 30%, constant speed control is applied until the stroke reaches 90%, which means that the target position is approaching. At this point, control is needed to avoid overshoot, and the third stage, deceleration control, is entered. The acceleration is continuously increased to reduce the control speed of the motor on the valve plate.

[0098] In one embodiment, during the opening and closing operation of the valve plate controlling the motor, in order to achieve overshoot-free arrival at the target endpoint, the method also sets up an anti-step-loss control strategy and an overshoot-free control strategy for control. Specifically, the following strategies can be used: Strategy A: S-curve acceleration / deceleration planning After the position loop outputs the speed command, the system uses an S-curve to generate an actual speed reference to avoid vibration caused by sudden acceleration changes.

[0099] Strategy B: Velocity Limiting and Acceleration Limiting When the valve approaches its end point, it automatically reduces the maximum speed to ensure that it reaches its destination without impact.

[0100] Strategy C: Anti-integral saturation Limit the integral terms of the position and velocity loops to prevent excessive integral accumulation due to sudden load changes, which could cause overshoot.

[0101] Strategy D: Feedforward Compensation for Friction and Vacuum Pressure Difference Based on the valve position and empirical models, feedforward torque is applied at the initial stage of opening and closing to improve start-up reliability.

[0102] Strategy E: Closed-loop step loss detection and protection A risk of losing synchronization is determined when the following conditions are met: Duration ,in, To allow for a speed error threshold, This is the threshold for the duration of the error.

[0103] or: and ,in, The minimum effective back electromotive force threshold, The speed threshold is used to determine the rotational speed.

[0104] This will trigger protection actions: speed reduction, current increase, pause, or alarm.

[0105] In another embodiment, during the process of controlling the valve plate of the motor to complete the opening and closing operation, the method further includes: acquiring the current estimated position of the valve plate and the corresponding target endpoint position; calculating the remaining travel distance between the current estimated position and the target endpoint position; determining whether the remaining travel distance is less than a preset deceleration threshold; if the remaining travel distance is less than the deceleration threshold, reducing the upper speed limit value corresponding to the speed control curve according to a preset speed limiting strategy; regenerating the target drive control quantity based on the reduced upper speed limit value, and controlling the motor to drive the valve plate to move to the target endpoint position. This is a strategy that dynamically limits the maximum speed based on the remaining distance to the endpoint. When the valve plate approaches the target endpoint position, the remaining travel distance decreases. Once the remaining travel distance is lower than the deceleration threshold, the speed limiting strategy is activated, forcibly reducing the maximum speed allowed by the speed control curve. This forces the valve plate to decelerate when approaching the endpoint, approaching the target at an extremely low speed, thereby effectively avoiding the valve plate impacting the sealing surface due to inertia or control overshoot.

[0106] In one embodiment, the aforementioned reduction of the upper speed limit corresponding to the speed control curve according to a preset speed limiting strategy includes: determining a corresponding target speed limit coefficient based on the remaining stroke; proportionally reducing the speed command output of the current position loop based on the target speed limit coefficient; calculating the corresponding target acceleration based on the reduced speed command; limiting the target acceleration when it exceeds a preset acceleration threshold; and updating the speed control curve based on the limited target acceleration. This embodiment refines the processes of speed limiting and acceleration limiting. First, the speed limit coefficient related to the remaining stroke is calculated by looking up a table or function, and the speed command is proportionally reduced. Subsequently, the new acceleration calculated from the reduced speed command may exceed the mechanical tolerance range, so secondary protection is introduced, namely, limiting the target acceleration. Finally, the speed control curve, which is simultaneously limited by speed and acceleration, ensures that the valve plate moves slowly at the end and that the acceleration and deceleration process is extremely smooth.

[0107] In one embodiment, both the position loop control logic and the speed control loop logic include an integral operation unit. The above-mentioned calculation of the motor drive control quantity based on the reference position quantity and the estimated position quantity using a preset dual-closed-loop control logic further includes: acquiring the integral cumulative quantity of the position loop control logic and the speed control loop logic respectively; determining whether the integral cumulative quantity exceeds the corresponding integral limit threshold; if the integral cumulative quantity exceeds the corresponding integral limit threshold, performing integral clamping processing on the integral cumulative quantity, and calculating the corresponding drive control quantity based on the integrally clamped integral cumulative quantity. In control theory, the integral term in a PI (proportional-integral) or PID controller is used to eliminate steady-state error. However, if the system has a large deviation for a long time, the integral term will accumulate infinitely, leading to "integral saturation," causing overshoot and long-term oscillation. This embodiment, by setting integral limit thresholds and integral clamping processing for the position loop control logic and the speed control loop logic respectively, forcibly limits the integral cumulative quantity to a reasonable range, effectively preventing integral saturation, improving the stability of the system under large-scale dynamic adjustment and fault conditions, and avoiding shocks to the valve plate due to integral runaway.

[0108] In one embodiment, the above-mentioned integral clamping processing of the integral accumulation includes: determining the actuator output state corresponding to the current drive control quantity; determining whether the actuator output state has reached a preset saturation condition; if the preset saturation condition is reached, pausing the integral accumulation operation of the corresponding control loop; resuming the integral accumulation operation when the actuator output state recovers to a non-saturated state; and continuing closed-loop control based on the recovered integral accumulation. This is a conditional integration or limit-reduced integration method. If the actuator output state, such as the drive pulse frequency or current amplitude, has reached its physical limit (e.g., maximum speed), i.e., reached the saturation condition, then no matter how much the integral term is increased, the output cannot be improved further. In this case, the algorithm intelligently pauses the integral accumulation operation, fundamentally avoiding saturation. Once the controller output exits the saturated state, the integral accumulation operation immediately resumes, ensuring the rapid response capability of the control. This strategy is more advanced and effective than simple amplitude limiting.

[0109] In one embodiment, during the opening and closing operation of the valve plate controlled by the motor, to enhance the system's resistance to load disturbances, the method further includes: acquiring the current estimated position, direction of motion, and vacuum system operating status parameters of the valve plate; determining corresponding load compensation parameters based on the current estimated position, direction of motion, and vacuum system operating status parameters; calculating a feedforward compensation amount based on the load compensation parameters; and superimposing the feedforward compensation amount with the output of the speed control loop logic to generate a new drive control amount. The speed control loop logic is adjusted based on "deviation" and belongs to feedback control, whose response always lags behind the disturbance. This embodiment introduces the concept of feedforward control. By acquiring the current position, direction of motion, and vacuum system operating status parameters (such as cavity pressure) of the valve plate, the upcoming load situation of the valve plate can be predicted in advance, such as the huge resistance that will be encountered when opening under atmospheric pressure difference. Based on this, the feedforward compensation amount is calculated and directly superimposed on the output of the speed control loop logic, which can compensate for load changes in advance, significantly improve the dynamic response of the system, and reduce the pressure of feedback control.

[0110] In one embodiment, the calculation of the feedforward compensation amount based on load compensation parameters includes: establishing a friction compensation model between the valve plate position and the friction torque; establishing a pressure difference compensation model between the vacuum pressure difference and the load torque; determining the corresponding target friction compensation amount based on the current valve plate position; determining the corresponding target pressure difference compensation amount based on the vacuum system operating state parameters; and calculating the feedforward compensation amount based on the target friction compensation amount and the target pressure difference compensation amount. This embodiment decomposes the feedforward compensation and models them separately. First, a friction compensation model is established to characterize how the friction torque changes with the valve plate position; second, a pressure difference compensation model is established to characterize how the vacuum pressure difference is converted into a load torque acting on the valve plate. During actual operation, the target friction compensation amount is found in the friction compensation model based on the current valve plate position, and the target pressure difference compensation amount is calculated in the pressure difference compensation model based on the vacuum system operating state parameters (such as upstream and downstream pressure differences). The two are added together to obtain the total feedforward compensation amount. This structured feedforward scheme provides more accurate compensation.

[0111] In one embodiment, during the opening and closing operation of the valve plate controlling the motor, a step loss monitoring and protection mechanism is also included: acquiring the real-time speed deviation of the motor and its corresponding duration; based on the real-time speed deviation, duration, and position deviation, determining whether the motor has a step loss risk; if so, determining the level of the step loss risk and adjusting the opening and closing operation of the valve plate based on the level. Step loss is one of the most fatal faults of a stepper motor. This embodiment continuously monitors the real-time speed deviation of the motor (i.e., the difference between the estimated speed and the commanded speed) and its duration. If the speed deviation is large and lasts for a long time, or if there is an unreducible deviation between the reference position and the estimated position, this strongly indicates the occurrence of a step loss risk. Once a step loss risk is determined and its severity level is identified, the system will take a series of graded adjustment measures, from reducing speed and increasing drive current to emergency stop alarms, to achieve proactive protection of the system.

[0112] As a specific implementation method, the judgment of the risk of loss of synchronization can be further realized through the following logic: when the absolute value of the real-time speed deviation... Greater than the allowable speed error threshold And the duration of this state is greater than the error duration threshold. When a step loss risk is detected, another independent criterion is that the absolute value of the difference between the back electromotive force characteristic quantity and the zero-point bias is... Less than the minimum effective back EMF threshold However, the speed command output of the position loop control logic... Greater than the speed determination threshold At the same time, it is also determined that there is a risk of loss of synchronization. The former detects "the command is seriously inconsistent with the actual situation and has not recovered for a long time", while the latter detects the abnormal state of "almost no back electromotive force can be measured under high-speed command". These two conditions complement each other and can comprehensively cover various fault characteristics of loss of synchronization.

[0113] It should be noted that, in some optional implementations, the aforementioned preset startup phase model, mathematical fitting model, calibration compensation, and mathematical model can all be generated by an automatic calibration program before the equipment leaves the factory. During the calibration process, the valve plate can be driven to perform a full-stroke reciprocating motion, while simultaneously recording the ECU input pulses, motor phase currents, back electromotive force signals, and data from an external standard reference position sensor. For scenarios where an external reference sensor cannot be installed, endpoint self-learning calibration can be performed based on mechanical limits. In other optional implementations, the temperature data for the temperature compensation strategy can come from the thermistors built into the motor or on the drive board, or the temperature can be indirectly calculated by estimating the change in motor winding resistance. Furthermore, the acceleration, constant speed, and deceleration parameters of the S-curve acceleration / deceleration planning algorithm, as well as the PID parameters of the position loop control logic and speed control loop logic in the dual closed-loop control logic, can all be adjusted according to the actual size, inertia, and response speed requirements of the vacuum butterfly valve to achieve optimal control performance.

[0114] In summary, by acquiring the back electromotive force signal generated inside the motor when driving the valve plate to rotate; determining whether the motor meets the preset low-speed condition based on the back electromotive force signal; estimating the motion state of the motor based on the target state estimation mode corresponding to the determination result, the motion state estimation includes at least the speed estimation; and driving the valve plate of the motor to complete the opening and closing operation through the preset closed-loop control logic based on the speed estimation. This achieves at least the following beneficial effects: Position and speed closed-loop control can be achieved without an external encoder, reducing cost and structural complexity; Eliminate low-speed and start-up blind spots to achieve full-stroke controllability of the valve plate; Reduce stepper motor step loss issues and improve valve plate position reliability; This enables the valve plate to open and close quickly, smoothly, and without overshoot, reducing pressure disturbances in the vacuum chamber. Reduce vibration, noise, and mechanical shock; improve valve life and system stability. Reduce energy consumption and heat generation by reducing excessive current output through closed-loop control.

[0115] The valve plate control method of the vacuum butterfly valve in the embodiments of this application has been described above. The valve plate control device of the vacuum butterfly valve in the embodiments of this invention is described below. Please refer to [link / reference]. Figure 6 One embodiment of the valve plate control device for the vacuum butterfly valve in this invention includes: The first acquisition module 410 is used to acquire the back electromotive force signal generated inside the motor when it drives the valve plate to rotate. The judgment module 420 is used to determine whether the motor meets the preset low-speed condition based on the back electromotive force signal, and to obtain the judgment result; The first estimation module 430 is used to estimate the motion state of the motor based on the target state estimation mode corresponding to the judgment result and the estimation logic corresponding to the target state estimation mode. The motion state estimation includes at least the speed estimation. The first drive control module 440 is used to drive the valve plate of the motor to complete the opening and closing operation based on the estimated speed through a preset closed-loop control logic.

[0116] In this embodiment, the first acquisition module 410 is specifically used for: The induced voltage signal generated by the detection winding of the motor when the motor drives the valve plate to rotate is obtained; The induced voltage signal is modulated to obtain the corresponding back electromotive force signal.

[0117] In this embodiment, the first acquisition module 410 is specifically used for: The induced voltage signal is input to the integral filter circuit, and a bias voltage and reset control logic are introduced to filter and calibrate the induced voltage signal to obtain a calibration voltage signal. After amplitude clamping protection processing is performed on the calibration voltage signal, analog-to-digital conversion sampling is performed to obtain the corresponding back electromotive force signal.

[0118] In this embodiment, the judgment module 420 is specifically used for: Extract the corresponding back EMF feature from the back EMF signal and determine whether the back EMF feature is greater than a preset validity threshold. If the back electromotive force characteristic is not greater than a preset validity threshold, then the motor is determined to be in a low-speed operating state. If the back electromotive force characteristic is greater than the preset validity threshold, the motor is determined to be in normal operating condition.

[0119] In this embodiment, the first estimation module 430 is specifically used for: If the judgment result is the low-speed operation state, the corresponding target state estimation mode is determined to be the model prediction estimation mode; the first speed estimate of the motor is estimated based on the control parameters of the motor and the preset start-up stage model; If the judgment result is the normal operating state, the corresponding target state estimation mode is determined to be the back EMF estimation mode; based on the back EMF characteristic quantity and the pre-established calibration compensation and mathematical model, the second speed estimate of the motor is estimated.

[0120] In this embodiment, the first estimation module 430 is specifically used for: The input pulses, cumulative microstep angles, and acceleration / deceleration plans of the motor are obtained and input into a preset start-up stage model to estimate the first speed of the motor.

[0121] In this embodiment, the first estimation module 430 is further configured to: A disturbance current of a preset amplitude is injected into the detection winding of the motor, and the current response change parameters of the detection winding after the disturbance are collected. The load state estimate and rotor hysteresis trend estimate of the motor are estimated based on the current response change parameters. The first speed estimate is corrected based on the load state estimate and the rotor hysteresis trend estimate.

[0122] In this embodiment, the first estimation module 430 is further configured to: Based on the estimated motion state of the motor, the corresponding fusion weight is determined, and the first speed estimate and the second speed estimate are fused and calculated based on a preset weighted fusion algorithm to obtain the final speed estimate.

[0123] In this embodiment, the first estimation module 430 is specifically used for: The current operating temperature of the motor is obtained, and the back electromotive force compensation coefficient is calculated and determined based on the operating temperature and the temperature compensation strategy. The back EMF compensation coefficient and the back EMF characteristic quantity are input into the pre-established calibration compensation and mathematical model estimation to obtain the second speed estimate.

[0124] In this embodiment, the valve plate control device of the vacuum butterfly valve further includes a model building module 450, used for: The zero-point bias of the back electromotive force of the valve plate in a static state and the characteristic quantity of the calibrated back electromotive force of the motor at each calibrated speed are collected. Based on the calibrated speed and the calibrated back EMF characteristic quantity, a relationship curve is plotted, and the relationship curve is fitted and temperature compensation is applied to obtain the calibration compensation and mathematical model of back EMF and speed.

[0125] In this embodiment, the device acquires the back electromotive force signal generated by the motor during the rotation of the valve plate, and determines whether the motor meets the preset low-speed condition based on the back electromotive force signal. Then, it selects the corresponding target state estimation mode according to the judgment result to estimate the motor motion state. Based on this, it uses the speed estimation to construct a dual closed-loop control logic to drive the valve plate to complete the opening and closing operation. Thus, it can realize real-time perception and closed-loop control of the valve plate motion state without configuring an external encoder. This solves the problem that the valve plate control of the existing vacuum butterfly valve cannot cover the start-up stage and low-speed stage, and the opening and closing control accuracy is low. At the same time, it can also effectively perceive the actual operating state of the motor, reduce the risk of loss of synchronization caused by load disturbance, and improve the valve plate positioning accuracy and operational reliability.

[0126] Please see Figure 7 This application also provides another embodiment of a valve plate control device for a vacuum butterfly valve, wherein the device is connected to a motor connected to the valve plate, and the device includes: The second acquisition module 510 is used to acquire the back electromotive force signal generated inside the motor when it drives the valve plate to rotate and the driving parameters at the current moment. The second estimation module 520 is used to estimate the reference position and speed of the motor based on the back electromotive force signal and the driving parameters using a preset motion state estimation logic. The second drive control module 530 is used to calculate the drive control quantity of the motor based on the reference position quantity and the estimated speed quantity through a preset dual closed-loop control logic. The preset dual closed-loop control logic includes a position loop control logic as the outer loop and a speed control loop logic as the inner loop. The speed command quantity is processed in a secondary manner using an S-curve acceleration and deceleration planning algorithm to generate a speed control curve containing multiple stages, and the drive control quantity is adjusted based on the speed control curve. The motor valve plate is controlled to complete the opening and closing operation based on the drive control quantity.

[0127] In this embodiment, the second estimation module 520 is specifically used for: Determine whether the back electromotive force signal meets the preset validity conditions; If not satisfied, the first speed estimate and reference position of the motor are estimated based on the input pulse, microstep angle accumulation and acceleration / deceleration planning in the driving parameters and input to the preset start-up stage model. If satisfied, the back EMF signal is input into a linear estimation model pre-constructed through calibration and compensation to estimate the second speed estimate of the motor. The first speed estimate and the second speed estimate are weighted and fused to obtain the speed estimate of the motor.

[0128] In this embodiment, the second drive control module 530 is specifically used for: The estimated position is obtained by integrating the estimated rotational speed. Based on the reference position and the estimated position, the drive control quantity of the motor is calculated through a preset dual closed-loop control logic.

[0129] In this embodiment, the second drive control module 530 is specifically used for: Based on the position deviation between the reference position and the estimated position, a speed command is generated through the position loop control logic in the preset dual closed-loop control logic. Based on the speed deviation between the speed command and the estimated speed, the drive control quantity of the motor is generated through the speed control loop logic in the preset dual closed-loop control logic.

[0130] In this embodiment, the second drive control module 530 is specifically used for: Based on the reduction ratio between the motor and the valve plate and the valve stem transmission ratio, the drive control quantity is converted into corresponding valve plate opening information, and the valve plate of the motor is controlled to complete the opening and closing operation.

[0131] In this embodiment, the second drive control module 530 is further configured to: Obtain the current estimated position of the valve plate and the corresponding target endpoint position; Calculate the remaining distance between the current estimated location and the target endpoint location; Determine whether the remaining travel distance is less than a preset deceleration threshold; If the remaining travel distance is less than the deceleration threshold, the upper speed limit value corresponding to the speed control curve is reduced according to the preset speed limiting strategy. Based on the reduced upper speed limit, the target drive control quantity is regenerated, and the motor is controlled to drive the valve plate to move to the target endpoint position.

[0132] In this embodiment, both the position loop control logic and the speed control loop logic include an integral operation unit; The second drive control module 530 is also specifically used for: The integral cumulative values ​​of the position loop control logic and the speed control loop logic are obtained respectively; Determine whether the accumulated points exceed the corresponding points limit threshold; If the cumulative integral exceeds the corresponding integral limit threshold, then the cumulative integral is clamped, and the corresponding drive control quantity is calculated based on the clamped cumulative integral.

[0133] In this embodiment, the second drive control module 530 is further configured to: Obtain the current estimated position, direction of movement, and vacuum system operating status parameters of the valve plate; The corresponding load compensation parameters are determined based on the current estimated position, the direction of motion, and the operating status parameters of the vacuum system. The feedforward compensation amount is calculated based on the load compensation parameters, and then the feedforward compensation amount is superimposed with the speed control loop logic output to generate a new drive control amount.

[0134] In this embodiment, the second drive control module 530 is further configured to: Obtain the real-time speed deviation of the motor and the corresponding duration; Based on the real-time speed deviation, the duration, and the position deviation, it is determined whether the motor is at risk of losing steps; If it exists, the level of the risk of loss of synchronization is determined, and the opening and closing operation of the valve plate is adjusted based on the level.

[0135] In this embodiment, the valve plate control device of the vacuum butterfly valve further includes a model building module 450, used for: The zero-point bias of the back electromotive force of the valve plate in a static state and the characteristic quantity of the calibrated back electromotive force of the motor at each calibrated speed are collected. Based on the calibrated speed and the calibrated back EMF characteristic quantity, a relationship curve is plotted, and the relationship curve is fitted and temperature compensation is applied to obtain the calibration compensation and mathematical model of back EMF and speed.

[0136] This device acquires the back electromotive force signal generated internally by the motor when driving the valve plate to rotate, along with the current driving parameters. Based on the back electromotive force signal and the driving parameters, it estimates the reference position and speed of the motor using a preset motion state estimation logic. Based on the reference position and the speed estimation, it calculates the driving control quantity of the motor using a preset dual closed-loop control logic. An S-curve acceleration / deceleration planning algorithm is used to perform secondary processing on the speed command quantity, generating a multi-stage speed control curve, and adjusting the driving control quantity based on the speed control curve. The valve plate is then controlled to complete the opening and closing operation based on the driving control quantity. This invention eliminates the need for external position sensors and solves the problem of difficult precise control of the valve plate during startup and low-speed phases due to weak back electromotive force signals by fusing estimation modes from different states, achieving precise closed-loop control of the valve plate throughout its entire stroke.

[0137] This embodiment also provides a vacuum butterfly valve device, including a processor and a memory. The memory stores machine-executable instructions that can be executed by the processor. The processor executes the machine-executable instructions to implement the valve plate control method of the vacuum butterfly valve described above. This vacuum butterfly valve device can be a server or a terminal device.

[0138] The vacuum butterfly valve device includes a vacuum chamber, a vacuum butterfly valve, and a valve plate control device for the vacuum butterfly valve as described in the above embodiments of this application. The vacuum butterfly valve is mounted on the vacuum chamber and connected to the valve plate control device. Because this vacuum butterfly valve device uses the control device provided in this application, its vacuum butterfly valve can achieve high-precision, low-disturbance opening and closing control, thereby ensuring stable vacuum levels within the process chamber and improving the yield of semiconductor processes.

[0139] In another embodiment, the vacuum butterfly valve device further includes a processor 800 and a memory 801, wherein the processor 800 and the memory 801 are equivalent to the valve plate control device of the vacuum butterfly valve, and the memory 801 stores machine-executable instructions that can be executed by the processor 800, which executes the machine-executable instructions to implement the valve plate control method of the vacuum butterfly valve described above.

[0140] Furthermore, Figure 8 The vacuum butterfly valve device shown also includes a bus 802 and a communication interface 803. The processor 800, the communication interface 803 and the memory 801 are connected via the bus 802.

[0141] The memory 801 may include high-speed random access memory (RAM) and may also include non-volatile memory, such as at least one disk storage device. Communication between this system network element and at least one other network element is achieved through at least one communication interface 803 (which can be wired or wireless), such as the Internet, wide area network, local area network, metropolitan area network, etc. The bus 802 may be an ISA bus, PCI bus, or EISA bus, etc. The bus can be divided into address bus, data bus, control bus, etc. For ease of representation, Figure 8 The symbol is represented by a single double-headed arrow, but this does not mean that there is only one bus or one type of bus.

[0142] The processor 800 may be an integrated circuit chip with signal processing capabilities. In implementation, each step of the above method can be completed by the integrated logic circuitry in the hardware of the processor 800 or by instructions in software form. The processor 800 may be a general-purpose processor, including a Central Processing Unit (CPU), a Network Processor (NP), etc.; it may also be a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field-Programmable Gate Array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. It can implement or execute the methods, steps, and logic block diagrams disclosed in the embodiments of this application. The general-purpose processor may be a microprocessor or any conventional processor. The steps of the methods disclosed in the embodiments of this application can be directly manifested as execution by a hardware decoding processor, or execution by a combination of hardware and software modules in the decoding processor. The software module can reside in a readily available storage medium in the art, such as random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, or registers. This storage medium is located in memory 801. The processor 800 reads information from memory 801 and, in conjunction with its hardware, completes the steps of the method described in the foregoing embodiments.

[0143] This embodiment also provides a computer-readable storage medium storing computer-executable instructions. When the computer-executable instructions are called and executed by a processor, the computer-executable instructions cause the processor to implement the valve plate control method of the vacuum butterfly valve described above.

[0144] The computer program product for the valve plate control method, vacuum butterfly valve device, and storage medium of the vacuum butterfly valve provided in this application includes a computer-readable storage medium storing program code. The instructions included in the program code can be used to execute the methods described in the preceding method embodiments. For specific implementation details, please refer to the method embodiments, which will not be repeated here.

[0145] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working process of the system and apparatus described above can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0146] Furthermore, in the description of the embodiments of this application, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0147] If the aforementioned functions are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0148] In the description of this application, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0149] Finally, it should be noted that the above embodiments are merely specific implementations of this application, used to illustrate the technical solutions of this application, and not to limit them. The protection scope of this application is not limited thereto. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any person skilled in the art can still modify or easily conceive of changes to the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some of the technical features, within the technical scope disclosed in this application. Such modifications, changes, or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be covered within the protection scope of this application. Therefore, the protection scope of this application should be determined by the protection scope of the claims.

Claims

1. A valve plate control method for a vacuum butterfly valve, applied to a valve opening control system, characterized in that, The valve opening control system includes at least a motor connected to the valve plate, and the method includes: Obtain the back electromotive force signal generated inside the motor when it drives the valve plate to rotate and the driving parameters at the current moment; Based on the back electromotive force signal and the driving parameters, the reference position and speed of the motor are estimated using a preset motion state estimation logic. Based on the reference position and the estimated speed, the drive control quantity of the motor is calculated through a preset dual closed-loop control logic, wherein the preset dual closed-loop control logic includes a position loop control logic as the outer loop and a speed control loop logic as the inner loop. An S-curve acceleration / deceleration planning algorithm is used to perform secondary processing on the speed command quantity to generate a speed control curve containing multiple stages, and the drive control quantity is adjusted based on the speed control curve. The motor's valve plate is controlled to perform opening and closing operations based on the drive control quantity.

2. The valve plate control method for the vacuum butterfly valve according to claim 1, characterized in that, The step of estimating the reference position and speed of the motor based on the back electromotive force signal and the driving parameters using a preset motion state estimation logic includes: Determine whether the back electromotive force signal meets the preset validity conditions; If not satisfied, the first speed estimate and reference position of the motor are estimated based on the input pulse, microstep angle accumulation and acceleration / deceleration planning in the drive parameters and input to the preset start-up stage model. If satisfied, the back EMF signal is input into a linear estimation model pre-constructed through calibration and compensation to estimate the second speed estimate of the motor. The first speed estimate and the second speed estimate are weighted and fused to obtain the speed estimate of the motor.

3. The valve plate control method for the vacuum butterfly valve according to claim 1, characterized in that, The calculation of the motor drive control quantity based on the reference position and the estimated rotational speed using preset dual-closed-loop control logic includes: The estimated position is obtained by integrating the estimated rotational speed. Based on the reference position and the estimated position, the drive control quantity of the motor is calculated through a preset dual closed-loop control logic.

4. The valve plate control method for the vacuum butterfly valve according to claim 3, characterized in that, The step of calculating the drive control quantity of the motor based on the reference position and the estimated position using a preset dual-closed-loop control logic includes: Based on the position deviation between the reference position and the estimated position, a speed command is generated through the position loop control logic in the preset dual closed-loop control logic. Based on the speed deviation between the speed command and the estimated speed, the drive control quantity of the motor is generated through the speed control loop logic in the preset dual closed-loop control logic.

5. The valve plate control method for the vacuum butterfly valve according to claim 1, characterized in that, In the process of controlling the valve plate of the motor to complete the opening and closing operation based on the drive control quantity, the following is also included: Obtain the current estimated position of the valve plate and the corresponding target endpoint position; Calculate the remaining distance between the current estimated location and the target endpoint location; Determine whether the remaining travel distance is less than a preset deceleration threshold; If the remaining travel distance is less than the deceleration threshold, the upper speed limit value corresponding to the speed control curve is reduced according to the preset speed limiting strategy. Based on the reduced upper speed limit, the target drive control quantity is regenerated, and the motor is controlled to drive the valve plate to move to the target endpoint position.

6. The valve plate control method for the vacuum butterfly valve according to claim 4, characterized in that, Both the position loop control logic and the speed control loop logic include an integral operation unit; The step of calculating the drive control quantity of the motor based on the reference position and the estimated position using a preset dual-closed-loop control logic further includes: The integral cumulative values ​​of the position loop control logic and the speed control loop logic are obtained respectively; Determine whether the accumulated points exceed the corresponding points limit threshold; If the cumulative integral exceeds the corresponding integral limit threshold, then the cumulative integral is clamped, and the corresponding drive control quantity is calculated based on the clamped cumulative integral.

7. The valve plate control method for the vacuum butterfly valve according to claim 5, characterized in that, In the process of controlling the valve plate of the motor to complete the opening and closing operation based on the drive control quantity, the following is also included: Obtain the current estimated position, direction of movement, and vacuum system operating status parameters of the valve plate; The corresponding load compensation parameters are determined based on the current estimated position, the direction of motion, and the operating status parameters of the vacuum system. The feedforward compensation amount is calculated based on the load compensation parameters, and then superimposed with the speed control loop logic output to generate a new drive control amount.

8. The valve plate control method for the vacuum butterfly valve according to claim 5, characterized in that, In the process of controlling the valve plate of the motor to complete the opening and closing operation based on the drive control quantity, the following is also included: Obtain the real-time speed deviation of the motor and the corresponding duration; Based on the real-time speed deviation, the duration, and the position deviation, it is determined whether the motor is at risk of losing synchronization. If it exists, the level of the risk of loss of synchronization is determined, and the opening and closing operation of the valve plate is adjusted based on the level.

9. A vacuum butterfly valve device, characterized in that, It includes a processor and a memory, the memory storing machine-executable instructions that can be executed by the processor, the processor executing the machine-executable instructions to implement the valve plate control method of the vacuum butterfly valve according to any one of claims 1-8.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the program is executed by the processor, it implements the valve plate control method for the vacuum butterfly valve as described in any one of claims 1-8.

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