Self-adjusting magnetic suspension pump and control method thereof

Abstract

The invention discloses a self-adjusting magnetic suspension pump and a control method thereof.The self-adjusting magnetic suspension pump comprises a magnetic suspension pump body, a viscosity detection module, a control module and a rotating speed adjusting module; the viscosity detection module is arranged at an inlet of the magnetic suspension pump body, and the viscosity detection module is used for detecting the viscosity parameter of a medium entering the pump body in real time; the control module is connected with the viscosity detection module and the rotating speed adjusting module, and the control module is used for determining the target rotating speed under the target flow according to the viscosity parameters and sending a rotating speed adjusting instruction to the rotating speed adjusting module according to the target rotating speed; the rotating speed adjusting module is used for adjusting the rotating speed to be the target rotating speed according to the rotating speed adjusting instruction, high-precision stable control over the outlet flow can be achieved, the stability of medium conveying in the semiconductor wet process is guaranteed, and the product machining quality and yield are improved.

Description

Technical Field

[0001] Embodiments of the present invention relate to the technical field of semiconductor manufacturing equipment, and in particular, to a self-regulating magnetic levitation pump and a control method thereof. Background Art

[0002] In semiconductor wet processes, magnetic levitation pumps are widely used in the transportation of media such as chemical solutions and ultrapure water due to their advantages of no mechanical contact, low wear, and high cleanliness. However, in the actual production process, the viscosity of the transported medium will fluctuate due to factors such as temperature changes and changes in the mixing ratio of chemical components.

[0003] Existing magnetic levitation pumps usually operate in a constant speed mode. When the viscosity of the medium changes, the output flow rate of the pump will fluctuate accordingly. Unstable flow rate will lead to problems such as insufficient cleaning and uneven etching in semiconductor wet processes, seriously affecting the yield and quality of semiconductor products. Summary of the Invention

[0004] The present invention provides a self-regulating magnetic levitation pump and a control method thereof, which can achieve a rapid response to changes in the viscosity of the medium, effectively overcome the lag problem of traditional flow feedback control, achieve high-precision stable control of the outlet flow rate, ensure the stability of the medium transportation in the semiconductor wet process, and improve the product processing quality and yield.

[0005] In a first aspect, embodiments of the present invention provide a self-regulating magnetic levitation pump, including: a magnetic levitation pump body, a viscosity detection module, a control module, and a speed regulation module;

[0006] The viscosity detection module is arranged at the inlet of the magnetic levitation pump body, and the viscosity detection module is used to detect the viscosity parameter of the medium entering the pump body in real time;

[0007] The control module is respectively connected to the viscosity detection module and the speed regulation module. The control module is used to determine the target speed at the target flow rate according to the viscosity parameter, and send a speed regulation instruction to the speed regulation module according to the target speed;

[0008] The speed regulation module is used to adjust the speed to the target speed according to the speed regulation instruction.

[0009] Optionally, the control module includes: a data model unit and a comparison unit;

[0010] The data model unit includes a pre-set relationship model between viscosity parameters, medium flow rate, and speed. The data model unit is used to match the target speed according to the viscosity parameter and the relationship model;

[0011] The comparison unit is connected to the data model unit. The comparison unit is configured to compare the target speed with the actual speed of the magnetic levitation pump at present, obtain a speed adjustment amount, and output the speed adjustment command according to the speed adjustment amount.

[0012] Optionally, the speed adjustment module includes an adjustment unit and a detection unit;

[0013] The adjustment unit is configured to adjust the speed of the magnetic levitation pump according to the speed adjustment command;

[0014] The detection unit is connected to the control module. The detection unit is configured to detect the actual speed of the magnetic levitation pump after adjustment and feedback it to the control module;

[0015] The control module further includes an optimization unit; the optimization unit is configured to optimize the speed adjustment command according to the comparison result between the adjusted actual speed and the target speed, so that the actual speed of the magnetic levitation pump remains at the target speed.

[0016] Optionally, the optimization unit optimizes the speed adjustment command based on the PID control algorithm.

[0017] Optionally, the viscosity detection module includes: a detection unit and a temperature compensation unit;

[0018] The detection unit is configured to detect the viscosity parameter of the medium;

[0019] The temperature compensation unit is connected to the detection unit. The temperature compensation unit is configured to correct the viscosity parameter according to the temperature parameter and output the corrected viscosity parameter.

[0020] Optionally, the detection unit includes a vibrating viscometer sensor.

[0021] In a second aspect, an embodiment of the present invention provides a control method for a self-regulating magnetic levitation pump. The magnetic levitation pump includes: a magnetic levitation pump body, a viscosity detection module, a control module, and a speed adjustment module;

[0022] The control method includes:

[0023] The viscosity detection module continuously detects the viscosity parameter of the medium entering the pump body;

[0024] The control module determines the target speed at the target flow rate according to the viscosity parameter, and sends a speed adjustment command to the speed adjustment module according to the target speed;

[0025] The speed adjustment module adjusts the speed to the target speed according to the speed adjustment command.

[0026] Optionally, the control module includes: a data model unit and a comparison unit;

[0027] The data model unit includes a relationship model among preset viscosity parameters, medium flow rate, and rotational speed. The data model unit is configured to match the target rotational speed according to the viscosity parameters and the relationship model;

[0028] The comparison unit is connected to the data model unit. The comparison unit is configured to compare the target rotational speed with the actual rotational speed of the current magnetic levitation pump to obtain a rotational speed adjustment amount, and output the rotational speed adjustment instruction according to the rotational speed adjustment amount.

[0029] Optionally, the rotational speed adjustment module includes an adjustment unit and a detection unit;

[0030] The adjustment unit adjusts the rotational speed of the magnetic levitation pump according to the rotational speed adjustment instruction;

[0031] The detection unit detects the actual rotational speed of the magnetic levitation pump after adjustment and feeds it back to the control module;

[0032] The control module further includes an optimization unit. The optimization unit optimizes the rotational speed adjustment instruction according to the comparison result between the adjusted actual rotational speed and the target rotational speed, so that the actual rotational speed of the magnetic levitation pump remains at the target rotational speed.

[0033] Optionally, the viscosity detection module includes: a viscosity detection unit and a temperature compensation unit;

[0034] The viscosity detection unit detects the viscosity parameters of the medium;

[0035] The temperature compensation unit corrects the viscosity parameters according to the temperature parameters and outputs the corrected viscosity parameters.

[0036] The magnetic levitation pump and its control method provided by the embodiments of the present invention, by setting a viscosity detection module at the inlet of the magnetic levitation pump body, using the viscosity detection module to detect the viscosity parameters of the passing medium in real time, and the control module analyzes and processes the viscosity parameters, can quickly respond to the change of the medium viscosity, and finally quickly adjust the rotational speed to the target rotational speed through the rotational speed adjustment module, realizing a quick response to the change of the medium viscosity, effectively overcoming the lag problem of traditional flow feedback control, realizing high-precision stable control of the outlet flow rate, ensuring the stability of medium transportation in the semiconductor wet process, and improving the product processing quality and yield. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a structural schematic diagram of a self-regulating magnetic levitation pump provided by an embodiment of the present invention;

[0038] Figure 2 This is a schematic structural diagram of another self - regulating magnetic levitation pump provided by an embodiment of the present invention;

[0039] Figure 3 This is a schematic flow diagram of a control method for a self - regulating magnetic levitation pump provided by an embodiment of the present invention. Detailed implementation manners

[0040] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Apparently, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0041] In semiconductor wet - process technology, magnetic levitation pumps are widely used in the transportation of media such as chemical liquids and ultrapure water due to their advantages of no mechanical contact, low wear, and high cleanliness. However, during the actual production process, the viscosity of the transported medium will fluctuate due to factors such as temperature changes and changes in the mixing ratio of chemical components.

[0042] Existing magnetic levitation pumps usually operate in a constant - speed mode. When the viscosity of the medium changes, the output flow rate of the pump will fluctuate accordingly. Unstable flow rates will lead to problems such as insufficient cleaning and uneven etching in semiconductor wet - process technology, seriously affecting the yield and quality of semiconductor products. Existing technologies have tried to increase flow sensors to monitor the outlet flow rate in real - time and feedback to adjust the pump speed, but this method has the problem of response lag and cannot quickly adapt to sudden changes in viscosity, still making it difficult to achieve precise and stable control of the flow rate.

[0043] In view of this, Figure 1 This is a schematic structural diagram of a self - regulating magnetic levitation pump provided by an embodiment of the present invention. Refer to Figure 1 , including: a magnetic levitation pump body 110, a viscosity detection module 120, a control module 130, and a speed regulation module 140;

[0044] The viscosity detection module 120 is arranged at the inlet of the magnetic levitation pump body 110, and the viscosity detection module 120 is used to detect the viscosity parameters of the medium entering the pump body in real - time;

[0045] The control module 130 is respectively connected to the viscosity detection module 120 and the speed regulation module 140. The control module 130 is used to determine the target speed at the target flow rate according to the viscosity parameters and send a speed regulation instruction to the speed regulation module 140 according to the target speed;

[0046] The speed regulation module 140 is used to adjust the speed to the target speed according to the speed regulation instruction.

[0047] Specifically, the magnetic levitation pump body 110 is supported by a non-contact magnetic levitation bearing for the rotor, and the rotor is driven to rotate at a high speed by electromagnetic force to achieve the transportation of the medium. The magnetic levitation pump body 110 can be made of corrosion-resistant materials and is applicable to the transportation of various chemical media and ultrapure water in semiconductor wet processes. Because there is no mechanical contact, it can ensure that the internal flow path is smooth and reduce the flow resistance of the medium. The viscosity detection module 120 is arranged at the medium inlet of the magnetic levitation pump body 110. The flowing medium will contact the viscosity detection module 120, and the viscosity detection module 120 detects the viscosity parameter of the medium entering the pump body in real time. Exemplarily, the viscosity detection module 120 can detect the viscosity parameter of the medium by means of vibration measurement or rotational resistance measurement. The control module 130 is the control core of the self-regulating magnetic levitation pump. The control module 130 can adopt an industrial microcontroller with functions such as storage and operation. The control module 130 can determine the target speed at the target flow rate according to the detected viscosity parameter. Exemplarily, a viscosity-flow rate-speed relationship model can be established in advance in the control module 130. According to the specific process requirements, the target flow rate can be known. By calling the viscosity-flow rate-speed relationship model and performing a matching query on the detected viscosity parameter, the corresponding target speed can be obtained. The control module 130 can convert the target speed into a corresponding speed adjustment instruction and send it to the speed adjustment module 140. The speed adjustment module 140 can adjust the speed to the target speed according to the speed adjustment instruction.

[0048] Exemplarily, taking the application of the magnetic levitation pump in the semiconductor wet process as an example, the magnetic levitation pump can be installed in the medium transportation pipeline of the semiconductor wet bench to ensure that the inlet of the magnetic levitation pump is connected to the medium storage container or the pre-stage processing unit, and the outlet of the magnetic levitation pump is connected to the wet process processing chamber. The medium enters the magnetic levitation pump through the inlet. The viscosity detection module 120 located at the pump inlet can detect the viscosity parameter of the medium accordingly. The control module 130 receives the viscosity parameter transmitted by the viscosity detection module 120, analyzes and processes it, and generates a corresponding speed adjustment instruction. The speed adjustment module 140 receives the speed adjustment instruction output by the control module 130 and adjusts the power supply frequency or current magnitude of the magnetic levitation pump drive motor according to the instruction requirements to achieve the speed of the magnetic levitation pump body 110 being the target speed.

[0049] The magnetic levitation pump provided by the embodiment of the present invention is provided with a viscosity detection module 120 at the inlet of the magnetic levitation pump body 110. By using the viscosity detection module 120 to detect the viscosity parameter of the passing medium in real time, and the control module 130 analyzes and processes the viscosity parameter, it can quickly respond to the change of the medium viscosity, and finally quickly adjust the rotation speed to the target rotation speed through the rotation speed adjustment module 140, realizing a quick response to the change of the medium viscosity, effectively overcoming the lag problem of the traditional flow feedback control, realizing high-precision stable control of the outlet flow, ensuring the stability of the medium transportation in the semiconductor wet process, and improving the product processing quality and yield.

[0050] Figure 2 The following is a schematic structural diagram of another self-regulating magnetic levitation pump provided by the embodiment of the present invention. Refer to Figure 2 , the control module 130 includes: a data model unit 131 and a comparison unit 132;

[0051] The data model unit 131 includes a relationship model among preset viscosity parameters, medium flow rate, and rotation speed. The data model unit 131 is used to match the target rotation speed according to the viscosity parameter and the relationship model;

[0052] The comparison unit 132 is connected to the data model unit 131. The comparison unit 132 is used to compare the target rotation speed with the actual rotation speed of the current magnetic levitation pump, obtain the rotation speed adjustment amount, and output a rotation speed adjustment instruction according to the rotation speed adjustment amount.

[0053] Specifically, the data model unit 131 stores a relationship model among preset viscosity parameters, medium flow rate, and rotation speed. The relationship model can be obtained through machine learning algorithms based on a large amount of experimental data. Among them, the machine learning algorithms can be modeled, trained, and verified based on existing learning algorithms. The relationship model is used to reflect the optimal target rotation speed corresponding to the viscosity parameter under different flow rates. Therefore, when the data model unit 131 receives the viscosity parameter, according to the requirement of the target flow rate, it can find and match the corresponding target rotation speed in the relationship model. The comparison unit 132 can compare the actual rotation speed of the current magnetic levitation pump with the target rotation speed, so as to calculate the rotation speed adjustment amount. For example, if the actual rotation speed of the current magnetic levitation pump is 200 r / min and the target rotation speed is 300 r / min, then the rotation speed adjustment amount is 100 r / min. The comparison unit 132 can output a rotation speed adjustment instruction corresponding to the rotation speed adjustment module 140 according to the rotation speed adjustment amount.

[0054] Based on the above embodiment, optionally, the rotation speed adjustment module 140 includes an adjustment unit 141 and a detection unit 142;

[0055] The adjustment unit 141 is used to adjust the rotation speed of the magnetic levitation pump according to the rotation speed adjustment instruction;

[0056] The detection unit 142 is connected to the control module 130. The detection unit 142 is used to detect the actual rotational speed of the magnetic levitation pump after adjustment and feedback it to the control module 130;

[0057] The control module 130 further includes an optimization unit 133; the optimization unit 133 is connected to the detection unit 142. The optimization unit 133 is used to compare the adjusted actual rotational speed with the target rotational speed and optimize the rotational speed adjustment command according to the comparison result, so that the actual rotational speed of the magnetic levitation pump is maintained at the target rotational speed.

[0058] Specifically, the adjustment unit 141 receives the rotational speed adjustment command and realizes rapid and precise adjustment of the pump rotational speed by changing the power supply frequency or current magnitude of the drive motor of the magnetic levitation pump. Among them, during the process of the adjustment unit 141 adjusting the magnetic levitation pump to the target rotational speed, the detection unit 142 can detect the real-time rotational speed of the magnetic levitation pump and feedback it to the optimization unit 133 of the control module 130. The optimization unit 133 compares the adjusted actual rotational speed with the target rotational speed. When there is a deviation between the adjusted actual rotational speed and the target rotational speed, for example, the difference between the adjusted actual rotational speed and the target rotational speed exceeds the reasonable range, the optimization unit 133 needs to optimize the rotational speed adjustment command, thereby finely adjusting the actual rotational speed to make the difference between the adjusted actual rotational speed and the target rotational speed within the reasonable range. Thus, the actual rotational speed of the magnetic levitation pump is maintained at the target rotational speed. Among them, the optimization unit 133 can use the commonly used proportional-integral-derivative (PID) control algorithm in the existing technology to calculate the rotational speed amount that needs to be adjusted between the adjusted actual rotational speed and the target rotational speed and generate the corresponding rotational speed adjustment command to achieve automatic adjustment. The core advantages of the PID algorithm are simple structure, strong robustness, easy implementation and wide applicability. Through the combination of the proportional (P), integral (I), and derivative (D) three links, this algorithm can effectively eliminate the steady-state error, suppress system oscillation, and achieve stable control without relying on an accurate mathematical model. The optimization unit 133 can dynamically adjust the rotational speed adjustment command according to the feedback actual rotational speed, continuously optimize the adjustment process until the actual rotational speed of the magnetic levitation pump is stable near the target rotational speed, thereby ensuring that the outlet flow rate is stable within the set target flow rate range.

[0059] And during the operation of the magnetic levitation pump, the viscosity detection module 120 can still continuously and real-time detect the change of the medium viscosity. Based on the above process, the control module 130 and the rotational speed adjustment module 140 continuously perform rotational speed adjustment according to the viscosity change, forming a dynamic closed-loop control process to ensure that throughout the semiconductor wet process, regardless of how the medium viscosity fluctuates, the magnetic levitation pump can stably transport the medium to meet the process requirements. When the process ends or the medium needs to be replaced, the magnetic levitation pump stops running according to the predetermined program and corresponding cleaning and maintenance operations can be carried out.

[0060] In the embodiment of the present invention, through the viscosity-flow-rotation speed relationship model built in the data model unit 131 and the control algorithm of PID, the magnetic levitation pump can have the ability of autonomous perception and adjustment, realize intelligent operation, reduce the technical requirements for operators, reduce manual intervention, and improve the production automation level. It can be applied to the transportation of media with various viscosity characteristics in semiconductor wet processes, without the need for complex manual parameter adjustment for different media, improving the versatility and production efficiency of the magnetic levitation pump.

[0061] Optionally, the viscosity detection module 120 includes: a viscosity detection unit and a temperature compensation unit;

[0062] The viscosity detection unit is used to detect the viscosity parameter of the medium;

[0063] The temperature compensation unit is connected to the viscosity detection unit, and the temperature compensation unit is used to correct the viscosity parameter according to the temperature parameter and output the corrected viscosity parameter.

[0064] Specifically, the viscosity detection unit includes a vibrating viscometer. The vibrating element of the vibrating viscometer is in full contact with the medium. As the viscosity of the medium changes, the vibration characteristics of the vibrating element change, and the signal processing circuit of the vibrating viscometer converts this physical change into an electrical signal. When the viscometer measures viscosity, it usually needs to be carried out at a certain temperature. However, the viscosity parameters at different temperatures are different because temperature affects the intermolecular friction and molecular motion ability of the liquid itself, thus affecting the accuracy of the viscosity measurement result. To eliminate the influence of temperature on the measurement result, the viscosity detection module 120 is also equipped with a temperature compensation unit. The temperature compensation unit can adopt dynamic temperature compensation or static temperature compensation. In the embodiment of the present invention, dynamic temperature compensation is taken as an example. When the temperature changes, the temperature compensation unit calculates the standardized viscosity parameter according to the temperature-viscosity relationship curve, so as to use the temperature compensation unit to correct the influence of temperature change on viscosity measurement. After being corrected by the temperature compensation unit, the viscosity parameter representing the viscosity of the medium is transmitted to the control module 130 in real time.

[0065] Figure 3 The following is a schematic flowchart of a control method for a self-regulating magnetic levitation pump provided by an embodiment of the present invention. This embodiment is applicable to the situation of flow control of semiconductor wet benches. This method can be executed by a self-regulating magnetic levitation pump, and this device can be implemented in a hardware and / or software manner. Combining Figure 1 , the method specifically includes the following steps:

[0066] S110. The viscosity detection module 120 detects the viscosity parameter of the medium entering the pump body in real time;

[0067] Specifically, the magnetic levitation pump body 110 uses a contactless magnetic levitation bearing to support the rotor, and drives the rotor to rotate at a high speed through electromagnetic force to achieve the transportation of the medium. The magnetic levitation pump body 110 can be made of corrosion-resistant materials and is applicable to the transportation of various chemical media and ultrapure water in semiconductor wet processes. Because there is no mechanical contact, it can ensure that the internal flow channel is smooth and reduce the medium flow resistance. The viscosity detection module 120 is arranged at the medium inlet of the magnetic levitation pump body 110, and the flowing medium will contact the viscosity detection module 120. The viscosity detection module 120 detects the viscosity parameters of the medium entering the pump body in real time. Exemplarily, the viscosity detection module 120 can detect the viscosity parameters of the medium by means of vibration measurement or rotational resistance measurement, etc.

[0068] S120. The control module 130 determines the target speed at the target flow rate according to the viscosity parameter, and sends a speed adjustment instruction to the speed adjustment module 140 according to the target speed;

[0069] Specifically, the control module 130 is the control core of the self-regulating magnetic levitation pump. The control module 130 can use an industrial microcontroller with functions such as storage and operation. The control module 130 can determine the target speed at the target flow rate according to the detected viscosity parameter. Exemplarily, a viscosity-flow rate-speed relationship model can be established in advance in the control module 130. According to specific process requirements, the target flow rate can be known. By calling the viscosity-flow rate-speed relationship model and performing matching queries on the detected viscosity parameter, the corresponding target speed can be obtained. The control module 130 can convert the target speed into a corresponding speed adjustment instruction and send it to the speed adjustment module 140.

[0070] S130. The speed adjustment module 140 adjusts the speed to the target speed according to the speed adjustment instruction.

[0071] Specifically, the speed adjustment module 140 can adjust the speed to the target speed according to the speed adjustment instruction.

[0072] Exemplarily, taking the application of the magnetic levitation pump in the semiconductor wet process as an example, the magnetic levitation pump can be installed in the medium transportation pipeline of the semiconductor wet processing machine to ensure that the inlet of the magnetic levitation pump is connected to the medium storage container or the pre-treatment unit, and the outlet of the magnetic levitation pump is connected to the wet process processing chamber. The medium enters the magnetic levitation pump through the inlet. The viscosity detection module 120 located at the pump inlet can detect the viscosity parameters of the medium accordingly. The control module 130 receives the viscosity parameters transmitted by the viscosity detection module 120, analyzes and processes them, and generates corresponding speed adjustment instructions. The speed adjustment module 140 receives the speed adjustment instructions output by the control module 130, and adjusts the power supply frequency or current magnitude of the magnetic levitation pump drive motor according to the instruction requirements to achieve the speed of the magnetic levitation pump body 110 being the target speed.

[0073] The control method of the magnetic levitation pump provided by the embodiment of the present invention sets a viscosity detection module 120 at the inlet of the magnetic levitation pump body 110, uses the viscosity detection module 120 to detect the viscosity parameter of the passing medium in real time, and the control module 130 analyzes and processes the viscosity parameter, can quickly respond to the change of the medium viscosity, and finally quickly adjusts the rotational speed to the target rotational speed through the rotational speed adjustment module 140, realizes quickly responding to the change of the medium viscosity, effectively overcomes the lag problem of the traditional flow feedback control, realizes the high-precision stable control of the outlet flow, ensures the stability of the medium transportation in the semiconductor wet process, and improves the product processing quality and yield.

[0074] Optionally, the control module 130 includes: a data model unit 131 and a comparison unit 132;

[0075] The control method further includes:

[0076] The data model unit 131 includes a relationship model among preset viscosity parameters, medium flow rate and rotational speed. The data model unit 131 is used to match the target rotational speed according to the viscosity parameter and the relationship model;

[0077] The comparison unit 132 is connected to the data model unit 131. The comparison unit 132 is used to compare the target rotational speed with the actual rotational speed of the current magnetic levitation pump, obtain the rotational speed adjustment amount, and output a rotational speed adjustment instruction according to the rotational speed adjustment amount.

[0078] Specifically, the data model unit 131 stores a relationship model among preset viscosity parameters, medium flow rate and rotational speed. The relationship model can be obtained by training through a machine learning algorithm based on a large amount of experimental data. Among them, the machine learning algorithm can be modeled, trained and verified based on the existing learning algorithms. The relationship model is used to reflect the optimal target rotational speed corresponding to the viscosity parameter under different flow rates. Therefore, when the data model unit 131 receives the viscosity parameter, according to the requirement of the target flow rate, it can search and match the corresponding target rotational speed in the relationship model. The comparison unit 132 can compare the actual rotational speed of the current magnetic levitation pump with the target rotational speed, so as to calculate the rotational speed adjustment amount. For example, the actual rotational speed of the current magnetic levitation pump is 200 r / min, and the target rotational speed is 300 r / min, then the rotational speed adjustment amount is 100 r / min. The comparison unit 132 can output a rotational speed adjustment instruction corresponding to the rotational speed adjustment module 140 according to the rotational speed adjustment amount.

[0079] Optionally, the rotational speed adjustment module 140 includes an adjustment unit 141 and a detection unit 142;

[0080] The control method further includes:

[0081] The adjustment unit 141 adjusts the rotational speed of the magnetic levitation pump according to the rotational speed adjustment instruction;

[0082] The detection unit 142 detects the actual rotational speed of the magnetic levitation pump after adjustment and feeds it back to the control module 130;

[0083] The control module 130 further includes an optimization unit 133; the optimization unit 133 optimizes the rotational speed adjustment instruction according to the comparison result between the adjusted actual rotational speed and the target rotational speed, so that the actual rotational speed of the magnetic levitation pump remains at the target rotational speed.

[0084] Specifically, the adjustment unit 141 receives the rotational speed adjustment instruction and realizes the fast and precise adjustment of the pump rotational speed by changing the power supply frequency or current magnitude of the driving motor of the magnetic levitation pump. Among them, during the process of the adjustment unit 141 adjusting the magnetic levitation pump to the target rotational speed, the detection unit 142 can detect the rotational speed of the magnetic levitation pump in real time and feed it back to the optimization unit 133 of the control module 130. The optimization unit 133 compares the adjusted actual rotational speed with the target rotational speed. When there is a deviation between the adjusted actual rotational speed and the target rotational speed, for example, the difference between the adjusted actual rotational speed and the target rotational speed exceeds the reasonable range, the optimization unit 133 needs to optimize the rotational speed adjustment instruction, thereby finely adjusting the actual rotational speed to make the difference between the adjusted actual rotational speed and the target rotational speed within the reasonable range. Thus, the actual rotational speed of the magnetic levitation pump is kept at the target rotational speed. Among them, the optimization unit 133 can use the PID control algorithm to calculate the rotational speed amount that needs to be adjusted between the adjusted actual rotational speed and the target rotational speed and generate the corresponding rotational speed adjustment instruction. The optimization unit 133 can dynamically adjust the rotational speed adjustment instruction according to the fed-back actual rotational speed, continuously optimize the adjustment process until the actual rotational speed of the magnetic levitation pump is stable near the target rotational speed, thereby ensuring that the outlet flow rate is stable within the set target flow rate range.

[0085] And during the operation of the magnetic levitation pump, the viscosity detection module 120 can still continuously and real-time detect the change of the medium viscosity. The control module 130 and the rotational speed adjustment module 140 continuously perform rotational speed adjustment according to the viscosity change, forming a dynamic closed-loop control process, ensuring that during the entire semiconductor wet process, no matter how the medium viscosity fluctuates, the magnetic levitation pump can stably transport the medium to meet the process requirements. When the process ends or the medium needs to be replaced, the magnetic levitation pump stops running according to the predetermined program and corresponding cleaning and maintenance operations can be carried out.

[0086] Through the viscosity-flow-rotational speed relationship model built in the data model unit 131 and the PID control algorithm in the embodiment of the present invention, the magnetic levitation pump can be made to have the ability of autonomous perception and adjustment, realize intelligent operation, reduce the technical requirements for operators, reduce manual intervention, and improve the production automation level. It can be applied to the transportation of media with various different viscosity characteristics in the semiconductor wet process, without the need for complex manual parameter adjustment for different media, improving the versatility and production efficiency of the magnetic levitation pump.

[0087] Optionally, the viscosity detection module 120 includes: a viscosity detection unit and a temperature compensation unit;

[0088] The viscosity detection unit detects the viscosity parameter of the medium;

[0089] The temperature compensation unit corrects the viscosity parameter according to the temperature parameter and outputs the corrected viscosity parameter.

[0090] Specifically, the viscosity detection unit includes a vibrating viscosity sensor. The vibrating element of the vibrating viscosity sensor is in full contact with the medium. As the viscosity of the medium changes, the vibration characteristics of the vibrating element change. The signal processing circuit of the vibrating viscosity sensor converts this physical change into an electrical signal. Considering the influence of temperature change on viscosity measurement, the viscosity detection module 120 is also equipped with a temperature compensation unit. By using experimental data, the relationship between temperature change and viscosity change is established. The temperature compensation unit is used to correct the influence of temperature change on viscosity measurement. After being corrected by the temperature compensation unit, the viscosity parameter representing the viscosity of the medium is transmitted to the control module 130 in real time.

[0091] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A self-regulating magnetic levitation pump, characterized in that, It includes: A magnetic levitation pump body, a viscosity detection module, a control module, and a speed regulation module; The viscosity detection module is arranged at the inlet of the magnetic levitation pump body, and the viscosity detection module is used to detect the viscosity parameter of the medium entering the pump body in real time; The control module is respectively connected to the viscosity detection module and the speed regulation module. The control module is used to determine the target speed at the target flow rate according to the viscosity parameter, and send a speed regulation instruction to the speed regulation module according to the target speed; The speed regulation module is used to adjust the speed to the target speed according to the speed regulation instruction.

2. The self-regulating magnetic levitation pump according to claim 1, wherein The control module includes: a data model unit and a comparison unit; The data model unit includes a pre-set relationship model between viscosity parameter, medium flow rate, and speed. The data model unit is used to match and obtain the target speed according to the viscosity parameter and the relationship model; The comparison unit is connected to the data model unit. The comparison unit is used to compare the target speed with the actual speed of the current magnetic levitation pump, obtain a speed regulation amount, and output the speed regulation instruction according to the speed regulation amount.

3. The self-regulating magnetic levitation pump according to claim 1, characterized in that, The speed regulation module includes an adjustment unit and a detection unit; The adjustment unit is used to adjust the speed of the magnetic levitation pump according to the speed regulation instruction; The detection unit is connected to the control module. The detection unit is used to detect the actual speed of the magnetic levitation pump after adjustment and feedback it to the control module; The control module further includes an optimization unit; the optimization unit is used to optimize the speed regulation instruction according to the comparison result between the adjusted actual speed and the target speed, so that the actual speed of the magnetic levitation pump remains at the target speed.

4. The self-regulating magnetic levitation pump according to claim 3, wherein The optimization unit optimizes the speed regulation instruction based on the PID control algorithm.

5. The self-regulating magnetic levitation pump according to claim 3, characterized in that, The viscosity detection module includes: a detection unit and a temperature compensation unit; The detection unit is used to detect the viscosity parameter of the medium; The temperature compensation unit is connected to the detection unit. The temperature compensation unit is used to correct the viscosity parameter according to the temperature parameter and output the corrected viscosity parameter.

6. The self-regulating magnetic levitation pump according to claim 5, wherein The detection unit includes a vibrating viscosity sensor.

7. A control method for a self-regulating magnetic levitation pump, characterized in that, The magnetic levitation pump includes: a magnetic levitation pump body, a viscosity detection module, a control module, and a speed regulation module; The control method includes: The viscosity detection module detects the viscosity parameter of the medium entering the pump body in real time; The control module determines the target speed at the target flow rate according to the viscosity parameter, and sends a speed regulation instruction to the speed regulation module according to the target speed; The speed regulation module adjusts the speed to the target speed according to the speed regulation instruction.

8. The control method of the self-regulating magnetic levitation pump according to claim 7, wherein, The control module includes: a data model unit and a comparison unit; The data model unit includes a pre-set relationship model between viscosity parameter, medium flow rate, and speed. The data model unit is used to match and obtain the target speed according to the viscosity parameter and the relationship model; The comparison unit is connected to the data model unit. The comparison unit is configured to compare the target speed with the actual speed of the magnetic levitation pump at present, obtain a speed adjustment amount, and output the speed adjustment command according to the speed adjustment amount.

9. The control method of the self-regulating magnetic levitation pump according to claim 7, wherein, The speed adjustment module includes an adjustment unit and a detection unit; The adjustment unit adjusts the speed of the magnetic levitation pump according to the speed adjustment command; The detection unit detects the actual speed of the magnetic levitation pump after adjustment and feeds it back to the control module; The control module further includes an optimization unit; the optimization unit optimizes the speed adjustment command according to the comparison result between the adjusted actual speed and the target speed, so that the actual speed of the magnetic levitation pump is maintained at the target speed.

10. The control method of the self-regulating magnetic levitation pump according to claim 7, wherein The viscosity detection module includes: a viscosity detection unit and a temperature compensation unit; The viscosity detection unit detects the viscosity parameter of the medium; The temperature compensation unit corrects the viscosity parameter according to the temperature parameter and outputs the corrected viscosity parameter.

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