Molecular pump full-speed-domain operation control method and device and medium

Abstract

The invention discloses a molecular pump full-speed-domain operation control method and device and a medium, and relates to the field of molecular pump operation control, and the technical scheme is characterized in that a control instruction is received, and whether the control instruction is a starting instruction or a stopping instruction is judged; when the control instruction is a starting instruction, the current rotating speed of the molecular pump is obtained, and a fast speed reduction algorithm, a sliding mode observation algorithm and a current frequency control algorithm are executed according to the size relation between the current rotating speed and a first rotating speed condition so that the molecular pump can run to the rated rotating speed; wherein the first rotating speed condition comprises a target rotating speed condition, a low critical rotating speed condition and a rotating speed zero condition; when the control instruction is a shutdown instruction, the current rotating speed of the molecular pump is obtained, and a fast speed reduction algorithm and a sliding mode observation algorithm are executed according to the size relation between the current rotating speed and a second rotating speed condition so that the rotating speed of the molecular pump can be reduced to zero; wherein the second rotating speed condition comprises three conditions of a preset rotating speed before shutdown, a low critical rotating speed and zero rotating speed.

Description

Technical Field

[0001] The present invention relates to the field of molecular pump operation control, and more particularly to a molecular pump full-speed range operation control method, equipment and medium. Background Art

[0002] Turbomolecular pumps, also known as turbomolecular pumps (TMP), can reach speeds of up to 90,000 rpm. They are essential equipment in the field of modern vacuum technology applications and are specifically used to generate and maintain high vacuum (HV) to ultra-high vacuum (UHV) environments (usually in the range of 10 -3 Pa to 10 -10 It overcomes the limitation of traditional mechanical pumps (such as vortex pumps and screw pumps) that the pumping speed drops sharply at low pressures, and is the basis for cutting-edge fields such as mass spectrometry analysis, semiconductor manufacturing, coating technology, surface science research, and particle accelerators.

[0003] However, the operation control of the ultra-high-speed motor of a molecular pump differs from that of an ordinary motor. Stable and reliable startup at any speed within the rated speed range is required, and speed data must be output throughout the entire process of startup acceleration and natural deceleration. Therefore, controlling the full-speed operation of the molecular pump is one of the key challenges affecting its reliable operation.

[0004] In the prior art, the molecular pump may receive a start or stop command at any time in the entire system. When the speed is low, the back electromotive force signal is too small, and the sliding mode observation algorithm cannot effectively estimate the speed and rotor position of the molecular pump motor, thereby failing to start the molecular pump directly. A more conventional method is to use a high-frequency injection algorithm and a flux control algorithm to estimate the speed and rotor position, and switch to a sliding mode observation algorithm when a certain speed is reached. However, since the saliency of the surface-mounted permanent magnet synchronous motor used in the molecular pump is not obvious, the effect of the high-frequency injection algorithm is limited, and high-frequency injection will bring new noise and vibration, affecting the performance of the product, and it is impossible to achieve 100% successful startup. Furthermore, the flux control algorithm will also cause strong initial vibration and poor load disturbance resistance during zero-speed startup. Both methods cannot guarantee 100% successful startup. In addition, the rated speed of the molecular pump is 90,000 revolutions per minute, which belongs to the ultra-high-speed operation range. In order to avoid the molecular pump being exposed to the atmosphere when the front pump is closed before it is completely stationary, causing the impeller components to be scratched or damaged, it is necessary to output the speed data during the entire process of speed reduction and shutdown. Due to the large operating speed range, the complexity of the back electromotive force signal processing circuit will be significantly increased, the reliability of the product will be reduced, and it is not conducive to the miniaturization design of the product. Summary of the Invention

[0005] The purpose of the present invention is to provide a molecular pump full-speed operation control method, equipment and medium, which solves the problem that the control method provided by the prior art cannot achieve reliable operation control of the molecular pump in the full speed range of startup speed increase and shutdown speed reduction.

[0006] The above technical objectives of the present invention are achieved through the following technical solutions: A first aspect of the present invention provides a method for controlling a molecular pump in full speed range, the method comprising: Receive a control command and determine whether the control command is a start command or a stop command; When the control instruction is a start instruction, the current speed of the molecular pump is obtained, and according to the relationship between the current speed and the first speed condition, the rapid deceleration algorithm, the sliding mode observation algorithm and the current frequency control algorithm are executed to make the molecular pump run to the rated speed; wherein the first speed condition includes the target speed, the low critical speed and the speed being zero; When the control instruction is a shutdown instruction, the current speed of the molecular pump is obtained, and the rapid deceleration algorithm and the sliding mode observation algorithm are executed according to the relationship between the current speed and the second speed condition to reduce the speed of the molecular pump to zero; wherein, the second speed condition includes three conditions: the speed preset before shutdown, the low critical speed and the speed of zero.

[0007] In one implementation, executing a rapid speed reduction algorithm, a sliding mode observation algorithm, and a current frequency control algorithm based on a magnitude relationship between the current speed and the first speed condition to make the speed of the molecular pump run to the rated speed includes: When the current speed is less than the target speed and less than the low critical speed, the rapid speed reduction algorithm is activated, a first current value when the rapid speed reduction algorithm is activated is collected, and a second coefficient for characterizing the speed is obtained based on a ratio of the current speed to the first current value; A second current value is collected during the process of starting the rapid speed reduction algorithm, and a second actual speed that satisfies both the target speed and the low critical speed is obtained based on the product of the second current value and the second coefficient; When the second actual speed is zero, the current frequency control algorithm is turned on to control the start of the molecular pump. When the operating speed of the molecular pump controlled by the current frequency control algorithm is greater than the low critical speed, the sliding mode observation algorithm is switched to estimate the motor speed and rotor position of the molecular pump in real time until it reaches the rated speed, and the start-up control of the molecular pump is ended.

[0008] In one implementation, the method further includes: When the current speed is greater than or equal to the target speed, the rapid speed reduction algorithm is activated, a first current value when the rapid speed reduction algorithm is activated is collected, and a first coefficient for representing the speed is obtained based on a ratio of the current speed to the first current value; wherein the first coefficient is greater than the second coefficient; The second current value during the process of starting the fast speed reduction algorithm is collected, and the first actual speed that meets the target speed is obtained according to the product of the second current value and the first coefficient, and the first actual speed is used as the current speed when the start command is received.

[0009] In one implementation, the method further includes: If the current speed is greater than or equal to the low critical speed, read the back electromotive force data at the current moment; The current molecular pump motor speed and rotor position are calculated based on the back electromotive force data, and then the sliding mode observation algorithm is switched to estimate the molecular pump motor speed and rotor position in real time, and the operation continues to the rated speed.

[0010] In one implementation, if the second actual speed is not zero, the rapid speed reduction algorithm is continuously executed until the second actual speed is reduced to zero; If the operating speed of the molecular pump controlled by the current frequency control algorithm is less than or equal to the low critical speed, the current frequency control algorithm is continuously executed until the operating speed of the molecular pump controlled by the current frequency control algorithm is greater than the low critical speed.

[0011] In one implementation, when the control instruction is a stop instruction, the current speed of the molecular pump is obtained, and according to the magnitude relationship between the current speed and the second speed condition, a rapid speed reduction algorithm and a sliding mode observation algorithm are executed to reduce the speed of the molecular pump to zero, including: When the current speed is less than the speed preset before shutdown and less than the low critical speed, the rapid speed reduction algorithm is activated, a first current value when the rapid speed reduction algorithm is activated is collected, and a fourth coefficient for characterizing the speed is obtained based on a ratio of the current speed to the first current value; A second current value is collected during the process of starting the rapid speed reduction algorithm, and a fourth actual speed that satisfies both the target speed and the low critical speed is obtained based on the product of the second current value and the fourth coefficient; When the fourth actual rotation speed is zero, the shutdown control of the molecular pump is completed.

[0012] In one implementation, the method further includes: When the current speed is greater than or equal to the speed preset before shutdown, the rapid speed reduction algorithm is activated, a first current value when the rapid speed reduction algorithm is activated is collected, and a third coefficient for representing the speed is obtained based on the ratio of the current speed to the first current value; wherein the third coefficient is greater than the fourth coefficient; The second current value during the process of starting the fast speed reduction algorithm is collected, and the third actual speed that meets the target speed is obtained according to the product of the second current value and the third coefficient, and the third actual speed is used as the current speed when the shutdown command is received.

[0013] In one implementation, the method further includes: If the current speed is greater than or equal to the low critical speed, the back electromotive force data at the current moment is read; The motor speed and rotor position of the molecular pump at the current moment are calculated according to the back electromotive force data until the current speed drops to the low critical speed.

[0014] A second aspect of the present invention provides a control device for a molecular pump, comprising a memory and a processor; a memory for storing a computer program, wherein the computer program includes program instructions; The processor is configured to execute the program instructions so as to enable the control device to perform the steps of a molecular pump full-speed operation control method provided by the first aspect of the present invention.

[0015] According to a third aspect of the present invention, a computer-readable storage medium is provided, wherein the computer-readable storage medium includes a computer program. When the computer program is executed by one or more processors, the computer program implements a molecular pump full-speed operation control method provided by the first aspect of the present invention.

[0016] Compared with the prior art, the present invention has the following beneficial effects: 1. This invention provides a full-speed range operation strategy. It first sets a low critical speed (approximately 3% of the rated speed). Upon receiving a start command, if the current speed is below the low critical speed, it is reduced to zero speed before starting using the current-frequency control algorithm. Then, it switches to the sliding-mode control algorithm. If the current speed is above the low critical speed, it starts directly using the sliding-mode control algorithm. Upon receiving a stop command, if the current speed is below the low critical speed, it is rapidly reduced to zero speed using the rapid deceleration algorithm. If the current speed is above the low critical speed, it is naturally decelerated. During operation, if a start or stop command is received and the current speed is below the low critical speed, it is rapidly reduced to zero speed using the rapid deceleration algorithm. This method eliminates the need for complex observation algorithms and achieves 100% start-up success.

[0017] 2. The present invention also provides a speed detection and output strategy for the molecular pump in the full speed range, that is, when the speed is lower than the low critical speed, whether in the startup state or the shutdown state, the current coefficient in the rapid deceleration method is used to characterize the speed of the molecular pump. When the speed is higher than the low critical speed, the speed of the molecular pump can be obtained according to the back electromotive force, thereby realizing the speed detection and output of the molecular pump in the full speed range. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The drawings described herein are used to provide a further understanding of the embodiments of the present invention, constitute a part of this application, and do not constitute a limitation of the embodiments of the present invention. In the drawings: Figure 1 A flowchart of a molecular pump full-speed operation control method provided by an embodiment of the present invention; Figure 2 A schematic flow chart of a method for controlling a molecular pump in full speed range according to an embodiment of the present invention; Figure 3 A graph showing the speed and current of a molecular pump in a stationary state during a start-stop test provided by an embodiment of the present invention; Figure 4 A graph showing the speed and current of a molecular pump start-stop test below a low critical speed provided by an embodiment of the present invention; Figure 5 This is a speed and current curve diagram of the start-stop test of the molecular pump above the low critical speed provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0019] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with examples and drawings. The exemplary embodiments of the present invention and their descriptions are only used to explain the present invention and are not intended to limit the present invention.

[0020] It should be noted that the terms "include" or "may include" used in various embodiments of the present application indicate the presence of the claimed function, operation or element, and do not limit the addition of one or more functions, operations or elements. In addition, as used in various embodiments of the present application, the terms "include", "have" and their cognates are only intended to indicate specific features, numbers, steps, operations, elements, components or combinations of the foregoing items, and should not be understood as first excluding the presence of one or more other features, numbers, steps, operations, elements, components or combinations of the foregoing items or the possibility of adding one or more features, numbers, steps, operations, elements, components or combinations of the foregoing items.

[0021] It should be understood that terms such as "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features indicated. Thus, a feature specified as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, "plurality" means two or more, unless otherwise specifically defined.

[0022] Please refer to Figure 1 , Figure 1 A flowchart of a molecular pump full-speed domain operation control method provided by an embodiment of the present invention is shown as follows: Figure 1 As shown, the method includes: S101, receiving a control instruction and determining whether the control instruction is a start instruction or a stop instruction.

[0023] In this embodiment, receiving a control instruction and determining its type are common knowledge in the technical field, and therefore no redundant description is given in this embodiment.

[0024] S102, when the control instruction is a start instruction, obtain the current speed of the molecular pump, and execute the rapid deceleration algorithm, the sliding mode observation algorithm and the current frequency control algorithm according to the relationship between the current speed and the first speed condition, so as to make the molecular pump run to the rated speed; wherein, the first speed condition includes the target speed, the low critical speed and the speed of zero.

[0025] In this embodiment, please refer to Figure 2 The left part of the flowchart shows the control process when the control instruction is a start instruction, which is as follows: When the current speed is less than the target speed and less than the low critical speed, the rapid speed reduction algorithm is activated, a first current value when the rapid speed reduction algorithm is activated is collected, and a second coefficient for characterizing the speed is obtained based on a ratio of the current speed to the first current value; A second current value is collected during the process of starting the rapid speed reduction algorithm, and a second actual speed that satisfies both the target speed and the low critical speed is obtained based on the product of the second current value and the second coefficient; When the second actual speed is zero, the current frequency control algorithm is turned on to control the start of the molecular pump. When the operating speed of the molecular pump controlled by the current frequency control algorithm is greater than the low critical speed, the sliding mode observation algorithm is switched to estimate the motor speed and rotor position of the molecular pump in real time until it reaches the rated speed, and the start-up control of the molecular pump is ended.

[0026] Among them, when the current speed is greater than or equal to the target speed, the rapid deceleration algorithm is turned on, and the first current value when the rapid deceleration algorithm is turned on is collected, and the first coefficient used to characterize the speed is obtained according to the ratio of the current speed to the first current value; wherein, the first coefficient is greater than the second coefficient; the second current value in the process of turning on the rapid deceleration algorithm is collected, and the first actual speed that meets the target speed is obtained according to the product of the second current value and the first coefficient, and the first actual speed is used as the current speed when the start command is received.

[0027] Among them, if the current speed is greater than or equal to the low critical speed, the back electromotive force data at the current moment is read; the motor speed and rotor position of the molecular pump at the current moment are calculated based on the back electromotive force data, and then the sliding mode observation algorithm is switched to estimate the electronic speed and rotor position of the molecular pump in real time, and continue to run to the rated speed.

[0028] Specifically, if the second actual speed is not zero, the rapid deceleration algorithm is continuously executed until the second actual speed is reduced to zero; if the operating speed of the molecular pump controlled by the current frequency control algorithm is less than or equal to the low critical speed, the current frequency control algorithm is continuously executed until the operating speed of the molecular pump controlled by the current frequency control algorithm is greater than the low critical speed.

[0029] Combined with the above control process, this embodiment is based on Figure 2 Taking the start command as an example, the full-speed domain control process of the start command is explained in detail. A low critical speed (about 3% of the rated speed) is set. When the start command is received, the current speed is first judged. If the current speed is lower than the low critical speed, it is reduced to zero speed and then started using the current frequency control algorithm. If the current speed is higher than the low critical speed, it is directly closed-loop started.

[0030] The specific implementation is: if it is a start command, first get the current speed oh , and determine the current speed oh Is it less than the set target speed? oh set , if the current speed oh Greater than the set target speed oh set , start the fast speed reduction algorithm, and according to the first current value I max Calculate the first coefficient that can be used to characterize the speed k 1. Then, collect the second current value during the process of starting the fast speed reduction algorithm i max , according to the first coefficient k 1 and the second current value, calculate the current first actual speed oh 1= k 1× i max At this time, after the speed reduction control of the rapid speed reduction algorithm, the current speed can be quickly reduced to the set target speed oh set ; If the current speed oh Less than the set target speed oh set , and then determine whether the current speed is less than the low critical speed oh 0, if the current speed oh Less than low critical speed oh 0, turn on the fast speed reduction algorithm and adjust the speed according to the first current value. I max Calculate the second coefficient that can be used to characterize the speed k 2, according to the second coefficient k 2Calculate the current second actual speed oh 2= k2× i max , until the second actual speed oh 2 quickly decreases to zero, and then executes the current frequency control algorithm to start the molecular pump until the second actual speed oh 2 Reaching low critical speed oh After 0, switch to the sliding mode observation algorithm to estimate the speed of the molecular pump motor in real time oh obs and location i obs , continue to run to the rated speed; if the current speed oh Greater than the lower critical speed oh 0, read the current back electromotive force data and calculate the current speed and rotor position, then switch to the sliding mode observation algorithm to estimate the speed of the molecular pump motor in real time oh obs and location i obs , and continue running to the rated speed.

[0031] S103, when the control instruction is a shutdown instruction, obtain the current speed of the molecular pump, and execute the rapid deceleration algorithm and the sliding mode observation algorithm according to the relationship between the current speed and the second speed condition to reduce the speed of the molecular pump to zero; wherein, the second speed condition includes three conditions: the speed preset before shutdown, the low critical speed, and the speed of zero.

[0032] For details, please refer to Figure 2 The right part of the flow chart shows the control process when the control instruction is a stop instruction, as follows: When the current speed is less than the speed preset before shutdown and less than the low critical speed, the rapid speed reduction algorithm is activated, a first current value when the rapid speed reduction algorithm is activated is collected, and a fourth coefficient for characterizing the speed is obtained based on a ratio of the current speed to the first current value; A second current value is collected during the process of starting the rapid speed reduction algorithm, and a fourth actual speed that satisfies both the target speed and the low critical speed is obtained based on the product of the second current value and the fourth coefficient; When the fourth actual rotation speed is zero, the shutdown control of the molecular pump is completed.

[0033] When the current speed is greater than or equal to the speed preset before shutdown, the rapid deceleration algorithm is activated, a first current value when the rapid deceleration algorithm is activated is collected, and a third coefficient for characterizing the speed is obtained based on the ratio of the current speed to the first current value; wherein the third coefficient is greater than the fourth coefficient; The second current value during the process of starting the fast speed reduction algorithm is collected, and the third actual speed that meets the target speed is obtained according to the product of the second current value and the third coefficient, and the third actual speed is used as the current speed when the shutdown command is received.

[0034] Among them, if the current speed is greater than or equal to the low critical speed, the back electromotive force data at the current moment is read; the motor speed and rotor position of the molecular pump at the current moment are calculated according to the back electromotive force data until the current speed drops to the low critical speed.

[0035] Combined with the above control process, this embodiment is based on Figure 2 For example, the full-speed domain control process of the stop command is described in detail. When a stop command is received, if it is a stop command, the current speed is obtained first. oh , and determine the current speed oh Is it less than the speed set before shutdown? oh set1 , if the current speed oh Greater than the speed set before shutdown oh set1 , start the fast speed reduction algorithm, and according to the first current value I max The third coefficient that can be used to characterize the speed is calculated k 3, according to the third coefficient k 3Calculate the current third actual speed oh 3= k 3× i max , the current third actual speed oh 3 Quickly reduce the speed to the set value oh set1 Then it will naturally slow down; if the current speed oh Lower than the speed set before shutdown oh set1 , and then determine whether the current speed is less than the low critical speed oh 0, if the current speed oh Less than low critical speed oh 0, turn on the fast speed reduction algorithm and adjust the speed according to the first current value. I max The fourth coefficient that can be used to characterize the speed is calculated k 4, according to the fourth coefficient k 4Calculate the current fourth time speed oh 4= k 4× i max , the current fourth time speed oh 4 Rapidly reduce to zero; if the current speed oh Greater than the lower critical speed oh 0, read the current back EMF data and calculate the current speed and rotor position natural deceleration.

[0036] The following is an actual application case to illustrate the technical effects of the present invention: In a molecular pump drive control project, the full-speed range operation control method of the present invention is used to drive and control a molecular pump with a rated speed of 90,000 rpm. The lower critical speed is set to 3,000 rpm.

[0037] Using the method of the present invention, the molecular pump is started in a stationary state, such as Figure 3 As shown, after receiving the start command, The current speed of the molecular pump is lower than the lower critical speed of 3000rpm. The execution condition calculates the second actual speed. At this time, the current speed of the molecular pump is zero, and the current frequency control is entered to start the molecular pump. When the speed is too high than the lower critical speed of 3000rpm, the sliding mode observation algorithm is switched to drive the rated speed to 90000rpm. The startup process is smooth and reliable. Figure 3 As shown in FIG, when the machine receives a shutdown command while running at a steady speed of 90,000 rpm, the target speed before shutdown is 90,000 rpm, so the machine decelerates naturally. When the speed naturally decelerates to the low critical speed of 3,000 rpm, the rapid deceleration algorithm is started, as shown in FIG. Figure 3 As shown, the molecular pump speed drops to zero quickly, the shutdown and speed reduction process is smooth and reliable, and the full range of speed values can be displayed.

[0038] Using the method of the present invention, the molecular pump is started at a low critical speed below 3000 rpm, such as Figure 4 As shown in the figure, when the machine starts from a stationary state and reaches about 12500rpm, a stop command is sent and the molecular pump naturally decelerates. When the molecular pump naturally decelerates to the low critical speed of 3000rpm, the fast deceleration algorithm is turned on to accelerate the molecular pump deceleration. Figure 4 As shown, a start command is sent at about 800rpm. The molecular pump speed is now lower than the low critical speed of 3000rpm, and the rapid deceleration algorithm is continued to be turned on. When the speed drops to zero, the molecular pump starts. At this time, the current speed of the molecular pump is zero, and the current frequency control is entered to start the molecular pump. When the speed is too high than the low critical speed of 3000rpm, the sliding mode observation algorithm is switched to drive it to about 16000rpm and the stop command is sent again. The molecular pump start is repeated below the low critical speed of 3000rpm. Figure 4 As shown in the figure, during multiple start and stop processes, the molecular pump can start and stop reliably and can display Displays the current speed value.

[0039] Using the method of the present invention, the molecular pump is started at a low critical speed of 3000 rpm or more, such as Figure 5As shown, after starting the molecular pump to about 1000rpm in a static state, a stop command is sent, and the molecular pump naturally slows down. A start command is sent again, and the molecular pump starts quickly. This test is repeated many times, and the molecular pump is started to the rated speed of 90000rpm. After the test is completed, a stop command is sent, and the molecular pump drops to zero speed. The whole process is smooth and reliable.

[0040] By adopting the method of the present invention, reliable operation control of the molecular pump in the full speed range of starting speed increase and stopping speed reduction can be achieved, 100% successful startup of the molecular pump in the full speed range can be achieved, the full range of speed can be displayed when the molecular pump starts speed increase and stops speed reduction, and a smooth transition between the starting and stopping states can be achieved.

[0041] The control method provided by the present invention has been verified on approximately 200 molecular pumps of the same model, with a startup success rate of 100%, demonstrating high reliability. Compared with the traditional full-speed domain operation control method, the full-speed domain operation control method of the present invention has obvious advantages: the success rate at any speed within the rated speed range of the molecular pump reaches 100%, and the full-speed domain speed detection output can be realized during the start and stop process of the molecular pump without introducing additional high-frequency noise and vibration. These improvements significantly improve the reliability of the full-speed domain operation control of the molecular pump and provide an effective solution for the optimization of the full-speed domain operation control of the molecular pump.

[0042] An embodiment of the present invention also provides a control device for a molecular pump. The control device includes a processor, a memory, a communication interface, and at least one communication bus for connecting the processor, the memory, and the communication interface. The memory includes, but is not limited to, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (PROM), or compact disc read-only memory (CD-ROM), and is used to store relevant instructions and data.

[0043] The communication interface is used to receive and send data. The processor can be one or more CPUs. When the processor is a CPU, the CPU can be a single-core CPU or a multi-core CPU. The processor in the control device is used to read one or more programs stored in the memory and perform the following operations: receiving a control instruction and determining whether the control instruction is a start instruction or a shutdown instruction; when the control instruction is a start instruction, obtaining the current speed of the molecular pump, and executing a rapid deceleration algorithm, a sliding mode observation algorithm, and a current frequency control algorithm based on the relationship between the current speed and a first speed condition to make the molecular pump run to the rated speed; wherein the first speed condition includes three conditions: target speed, low critical speed, and zero speed; when the control instruction is a shutdown instruction, obtaining the current speed of the molecular pump, and executing a rapid deceleration algorithm and a sliding mode observation algorithm based on the relationship between the current speed and a second speed condition to reduce the speed of the molecular pump to zero; wherein the second speed condition includes three conditions: a speed preset before shutdown, a low critical speed, and zero speed.

[0044] It should be noted that the specific implementation of each operation can be as described above. Figure 1 The corresponding description of the method embodiment shown is that the control device can be used to execute a molecular pump full-speed operation control method of the above method embodiment of the present application, which will not be described in detail here.

[0045] The embodiment of the present invention further provides a computer-readable storage medium, which is a memory device in a computer device for storing programs and data. It is understandable that the computer-readable storage medium here can include both built-in storage media in the computer device and, of course, extended storage media supported by the computer device. The computer-readable storage medium provides a storage space that stores the operating system of the terminal. In addition, one or more instructions suitable for being loaded and executed by the processor are also stored in the storage space. These instructions can be one or more computer programs (including program codes). It should be noted that the computer-readable storage medium here can be a high-speed RAM memory or a non-volatile memory (non-volatile memory), such as at least one disk memory. The processor can load and execute one or more instructions stored in the computer-readable storage medium to implement the corresponding steps of the full-speed domain operation control method of a molecular pump in the above embodiment. Those skilled in the art should understand that the embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes.

[0046] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A molecular pump full speed range operation control method, characterized in that: Methods include: Receive a control command and determine whether the control command is a start command or a stop command; When the control instruction is a start instruction, the current speed of the molecular pump is obtained, and according to the relationship between the current speed and the first speed condition, the rapid deceleration algorithm, the sliding mode observation algorithm and the current frequency control algorithm are executed to make the molecular pump run to the rated speed; wherein the first speed condition includes the target speed, the low critical speed and the speed being zero; When the control instruction is a shutdown instruction, the current speed of the molecular pump is obtained, and the rapid deceleration algorithm and the sliding mode observation algorithm are executed according to the relationship between the current speed and the second speed condition to reduce the speed of the molecular pump to zero; wherein, the second speed condition includes three conditions: the speed preset before shutdown, the low critical speed and the speed of zero.

2. A molecular pump full speed range operation control method according to claim 1, characterized in that: The method of executing a rapid speed reduction algorithm, a sliding mode observation algorithm, and a current frequency control algorithm according to a magnitude relationship between the current speed and the first speed condition to make the speed of the molecular pump run to the rated speed includes: When the current speed is less than the target speed and less than the low critical speed, the rapid speed reduction algorithm is activated, a first current value when the rapid speed reduction algorithm is activated is collected, and a second coefficient for characterizing the speed is obtained based on a ratio of the current speed to the first current value; A second current value is collected during the process of starting the rapid speed reduction algorithm, and a second actual speed that satisfies both the target speed and the low critical speed is obtained based on the product of the second current value and the second coefficient; When the second actual speed is zero, the current frequency control algorithm is turned on to control the start of the molecular pump. When the operating speed of the molecular pump controlled by the current frequency control algorithm is greater than the low critical speed, the sliding mode observation algorithm is switched to estimate the motor speed and rotor position of the molecular pump in real time until it reaches the rated speed, and the start-up control of the molecular pump is ended.

3. A molecular pump full speed range operation control method according to claim 2, characterized in that: Also includes: When the current speed is greater than or equal to the target speed, the rapid speed reduction algorithm is activated, a first current value when the rapid speed reduction algorithm is activated is collected, and a first coefficient for representing the speed is obtained based on a ratio of the current speed to the first current value; wherein the first coefficient is greater than the second coefficient; The second current value during the process of starting the fast speed reduction algorithm is collected, and the first actual speed that meets the target speed is obtained according to the product of the second current value and the first coefficient, and the first actual speed is used as the current speed when the start command is received.

4. A molecular pump full speed range operation control method according to claim 2, characterized in that: Also includes: If the current speed is greater than or equal to the low critical speed, read the back electromotive force data at the current moment; The current molecular pump motor speed and rotor position are calculated based on the back electromotive force data, and then the sliding mode observation algorithm is switched to estimate the molecular pump motor speed and rotor position in real time, and the operation continues to the rated speed.

5. A molecular pump full speed range operation control method according to claim 2, characterized in that: If the second actual speed is not zero, the rapid speed reduction algorithm is continuously executed until the second actual speed is reduced to zero; If the operating speed of the molecular pump controlled by the current frequency control algorithm is less than or equal to the low critical speed, the current frequency control algorithm is continuously executed until the operating speed of the molecular pump controlled by the current frequency control algorithm is greater than the low critical speed.

6. A molecular pump full speed range operation control method according to claim 1, characterized in that: When the control instruction is a stop instruction, the current speed of the molecular pump is obtained, and according to the relationship between the current speed and the second speed condition, a rapid speed reduction algorithm and a sliding mode observation algorithm are executed to reduce the speed of the molecular pump to zero, including: When the current speed is less than the speed preset before shutdown and less than the low critical speed, the rapid speed reduction algorithm is activated, a first current value when the rapid speed reduction algorithm is activated is collected, and a fourth coefficient for characterizing the speed is obtained based on a ratio of the current speed to the first current value; A second current value is collected during the process of starting the rapid speed reduction algorithm, and a fourth actual speed that satisfies both the target speed and the low critical speed is obtained based on the product of the second current value and the fourth coefficient; When the fourth actual rotation speed is zero, the shutdown control of the molecular pump is completed.

7. A molecular pump full speed range operation control method according to claim 6, characterized in that: Also includes: When the current speed is greater than or equal to the speed preset before shutdown, the rapid speed reduction algorithm is activated, a first current value when the rapid speed reduction algorithm is activated is collected, and a third coefficient for representing the speed is obtained based on the ratio of the current speed to the first current value; wherein the third coefficient is greater than the fourth coefficient; The second current value during the process of starting the fast speed reduction algorithm is collected, and the third actual speed that meets the target speed is obtained according to the product of the second current value and the third coefficient, and the third actual speed is used as the current speed when the shutdown command is received.

8. A molecular pump full speed range operation control method according to claim 6, characterized in that: Also includes: If the current speed is greater than or equal to the low critical speed, the back electromotive force data at the current moment is read; The motor speed and rotor position of the molecular pump at the current moment are calculated according to the back electromotive force data until the current speed drops to the low critical speed.

9. A control device for a molecular pump, characterized in that: including memory and processor; a memory for storing a computer program, wherein the computer program includes program instructions; The processor is configured to execute the program instructions so that the control device performs the steps of the full-speed range operation control method of a molecular pump according to any one of claims 1 to 8.

10. A computer-readable storage medium, characterized in that The computer-readable storage medium includes a computer program, and when the computer program is executed by one or more processors, the computer program implements the full-speed range operation control method of a molecular pump according to any one of claims 1 to 8.

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