Magnetic levitation molecular pump temperature control method, computer device and magnetic levitation molecular pump

Abstract

The application relates to the technical field of magnetic suspension, in particular to a magnetic suspension molecular pump temperature control method, computer equipment and a magnetic suspension molecular pump. The method comprises the following steps: obtaining operation data of the magnetic suspension molecular pump; independently performing anti-deposition heating demand analysis, thermal zone coordination analysis and safety power analysis based on the operation data; determining candidate power of each heating channel according to a demand heating power and a power correction amount, and determining final output power of each heating channel under the constraints of a total heating power upper limit and a safety heating power upper limit of each heating channel; and controlling the heating channels corresponding to a first traction stage thermal zone, a second traction stage thermal zone and an air outlet thermal zone to work according to the final output power. The technical scheme provided by the application reasonably controls the temperature of the magnetic suspension molecular pump for the purpose of preventing deposition, and improves the operation stability and safety.

Description

Technical Field

[0001] This application relates to the field of magnetic levitation technology, and in particular to a temperature control method for a magnetic levitation molecular pump, a computer device, and a magnetic levitation molecular pump. Background Technology

[0002] Magnetic levitation molecular pumps utilize magnetic bearings for contactless support of high-speed rotors, featuring oil-free operation, low vibration, high cleanliness, and long lifespan. They are widely used in vacuum processes such as semiconductor etching, thin film deposition, ion implantation, and vacuum coating. During these processes, process gases and reaction byproducts can easily condense, deposit, or solidify in areas such as the traction stage, threaded grooves, and outlet of the molecular pump. Continuous accumulation of deposits can narrow the gas flow path, increase the pump load, and in severe cases, affect the normal operation of the molecular pump. Therefore, it is usually necessary to increase the temperature of these areas through heating to reduce the risk of condensation and deposition of reaction byproducts.

[0003] Existing temperature management solutions for molecular pumps typically employ overall or partial heating of the pump base, foundation, or other pump body components, combined with external heating elements, water cooling, temperature sensors, and over-temperature protection to achieve temperature control. For magnetically levitated molecular pumps, overall heating easily leads to heat transfer to temperature-sensitive components such as the motor, magnetic bearings, and displacement sensors. External heating methods suffer from long heat transfer paths, and the contact state and heat transfer efficiency are easily affected by installation conditions, making it difficult to simultaneously ensure effective heating of areas at risk of deposition and temperature control of other components. Furthermore, the thermal state of magnetically levitated molecular pumps changes under different operating stages and process conditions. Simply relying on fixed temperature thresholds or relatively independent temperature control loops for heating and cooling is insufficient to adequately meet the requirements of high-temperature anti-deposition operation and the thermal safety of magnetically levitated components.

[0004] Therefore, there is an urgent need for a temperature control method suitable for magnetic levitation molecular pumps, so as to reasonably control the temperature of magnetic levitation molecular pumps for the purpose of preventing deposition, thereby improving operational stability and safety. Summary of the Invention

[0005] This application provides a temperature control method, computer equipment, and magnetic levitation molecular pump for magnetic levitation molecular pumps, which can reasonably control the temperature of magnetic levitation molecular pumps to prevent deposition, thereby improving operational stability and safety.

[0006] To achieve the above objectives, the main technical solutions adopted in this application include: In a first aspect, embodiments of this application provide a temperature control method for a magnetically levitated molecular pump. The magnetically levitated molecular pump is provided with a first traction stage hot zone located above the traction stage, a second traction stage hot zone located below the traction stage, and an outlet hot zone. The first traction stage hot zone, the second traction stage hot zone, and the outlet hot zone are each provided with an independent heating channel. The method includes: Obtain the operating data of the magnetically levitated molecular pump; Based on the operational data, anti-deposition heating demand analysis, thermal zone coordination analysis, and safe power analysis are performed independently. Specifically, the anti-deposition heating demand analysis determines the required heating power of each heating channel, the thermal zone coordination analysis determines the power correction amount of each heating channel according to the thermal coupling relationship between each thermal zone, and the safe power analysis determines the upper limit of the total heating power of the magnetic levitation molecular pump and the upper limit of the safe heating power of each heating channel. The candidate power of each heating channel is determined based on the required heating power and the power correction amount, and the final output power of each heating channel is determined under the constraints of the total heating power limit and the safe heating power limit of each heating channel. The heating channels corresponding to the first traction stage hot zone, the second traction stage hot zone, and the outlet hot zone are controlled to operate according to the final output power.

[0007] The temperature control method for a magnetic levitation molecular pump proposed in this application sets independent heating channels in the first traction stage hot zone, the second traction stage hot zone, and the outlet hot zone. Based on the operating data of the magnetic levitation molecular pump, it independently performs anti-deposition heating demand analysis, hot zone coordination analysis, and safe power analysis. This allows the power determination of each heating channel to take into account the actual heating demand of the corresponding hot zone, the thermal coupling effect between different hot zones, and the current allowable heating power range of the magnetic levitation molecular pump. Furthermore, it forms candidate power based on the required heating power and power correction amount, and uses the upper limit of the total heating power and the upper limit of the safe heating power of each heating channel to constrain the candidate power. This avoids problems such as insufficient local heating, temperature imbalance caused by thermal coupling, and heating power exceeding the thermal safety tolerance caused by relying solely on a single temperature threshold or independent control of each hot zone. Thus, it achieves coordinated temperature control between multiple hot zones while meeting the anti-deposition heating demand, and limits the heating power of the whole machine and each heating channel within the allowable range, improving the rationality, stability, and safety of the temperature control of the magnetic levitation molecular pump.

[0008] Secondly, embodiments of this application provide a computer device, including: The system includes a memory and a processor, which are communicatively connected to each other. The memory stores computer instructions, and the processor executes the computer instructions to perform the magnetic levitation molecular pump temperature control method described in the first aspect.

[0009] Thirdly, this application provides a magnetic levitation molecular pump, which is provided with a first traction stage hot zone located at the upper part of the traction stage, a second traction stage hot zone located at the lower part of the traction stage, and an outlet hot zone. The first traction stage hot zone, the second traction stage hot zone, and the outlet hot zone are each provided with an independent heating channel. The magnetically levitated molecular pump is also equipped with the computer equipment described in the second aspect. Attached Figure Description

[0010] To more clearly illustrate the technical solutions in the specific embodiments of this application or 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.

[0011] Figure 1 A step diagram illustrating a method for temperature control of a magnetically levitated molecular pump provided in this application embodiment; Figure 2 This is a schematic diagram of the structure of a magnetic levitation molecular pump and its control box provided in an embodiment of this application; Figure 3 A structural diagram of a magnetic levitation molecular pump temperature control device provided in this application embodiment; Figure 4 This is a schematic diagram of the structure of a computer device provided in an embodiment of this application. Detailed Implementation

[0012] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments 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.

[0013] Before describing the embodiments of this application, the magnetic levitation molecular pump and the temperature control object involved in this application will be described first. The magnetic levitation molecular pump utilizes magnetic bearings to provide contactless support for a high-speed rotor. During operation, process gases and reaction byproducts are discharged downstream along the gas channels inside the pump, and are prone to condensation, deposition, or solidification at locations with relatively low temperatures or changes in flow conditions, such as the traction stage, threaded grooves, and gas outlet. For the magnetic levitation molecular pump, it is generally desirable to maintain a high temperature in the anti-deposition area. However, components such as magnetic bearings, motors, and displacement sensors are temperature-sensitive components. Therefore, it is necessary to increase the temperature of the deposition-risk area while limiting heat transfer to the bearing-sensitive area.

[0014] like Figure 2 As shown, in one engineering embodiment, the magnetic levitation molecular pump can adopt the structure of the KTP-800 high-heat version. Figure 2 The upper part of the diagram shows the main structure, 45° view, and water-cooled structure of the molecular pump, while the lower part shows the magnetic levitation control box and the heating control box. The magnetic levitation control box can serve as the main control unit, used for starting, stopping, accelerating, stabilizing, and decelerating the molecular pump, controlling magnetic bearing levitation, adjusting speed, detecting faults, and providing operational protection. The heating control box can serve as the heating control unit, used for multi-channel heating control, water-cooling linkage, fault reporting, and various temperature control calculations described later. The main control unit and the heating control unit can be set up separately or integrated into a single controller, industrial computer, host computer, or control board. Communication between the two can be via RS232, RS485, CAN, EtherCAT, Ethernet, or other communication methods capable of transmitting operating status, fault status, and heating feedback.

[0015] The first embodiment of this application provides a temperature control method for a magnetically levitated molecular pump. The magnetically levitated molecular pump is provided with a first traction stage hot zone located above the traction stage, a second traction stage hot zone located below the traction stage, and an outlet hot zone. The first traction stage hot zone, the second traction stage hot zone, and the outlet hot zone are each provided with an independent heating channel.

[0016] Specifically, in this embodiment, the controlled area directly related to deposition risk is divided into a first traction stage hot zone Z1, a second traction stage hot zone Z2, and an outlet hot zone Z3. Z1 specifically corresponds to the upstream traction stage, the inlet side of the threaded groove, and the adjacent gas channel; Z2 specifically corresponds to the downstream traction stage, the end of the threaded groove, and the intermediate exhaust channel; and Z3 specifically corresponds to the outlet, the exhaust-side transition area, and the downstream location prone to condensation and blockage. Each of the three hot zones is equipped with an independent heating channel, which can be connected to the first traction stage heating module H1, the second traction stage heating module H2, and the outlet heating module H3, respectively, so that the local heating area corresponds to the location of deposition risk.

[0017] In one embodiment, each heating module adopts an embedded structure and includes a heating rod, a temperature sensor, and a mechanical over-temperature protection device. The embedded structure can be achieved by providing blind holes, stepped holes, arc-shaped mounting grooves, or mating surface grooves on the traction stage housing, the gas outlet connector, or adjacent thermally conductive substrate, so that the heating rod is arranged close to the gas flow path along the axial, circumferential, or tangential direction; the heating rod and the mounting position can adopt a transition fit, thermally conductive filler, or compression structure to improve thermal conductivity stability; the temperature sensor can be set at a temperature measuring position between the heating rod and the deposition risk surface or close to the deposition risk surface.

[0018] In one specific embodiment, the heating rod can be a 200 W / 220 VAC AC heating rod, the temperature sensor can be a PT1000, and the power limit of each heating channel can be set independently, for example, not exceeding 500W.

[0019] In one embodiment, a water-cooling module can also be installed in the pump body, pump bottom, or bearing sensitive area of ​​the magnetic levitation molecular pump to remove heat from non-target areas. Localized embedded heating and water cooling of the pump body or bearing sensitive area employ different thermal execution paths, thereby spatially decoupling the localized heating of the anti-deposition area from the cooling of the temperature-sensitive components.

[0020] like Figure 1 As shown, the method flow specifically includes the following steps. It should be noted that the steps shown in the flowchart can be executed in a computer system such as a set of computer-executable instructions. Furthermore, although a logical order is shown in the flowchart, in some cases, the steps shown or described may be performed in a different order than that shown here: Step 110: Obtain the operating data of the magnetic levitation molecular pump.

[0021] In this embodiment, the operational data is used to describe the current and historical operational status, thermal status, and heating execution status of the magnetically levitated molecular pump. The operational data may include the molecular pump's operational stage, process status, rotational speed, magnetic levitation status, main control unit fault status, communication heartbeat, first traction stage hot zone temperature T1, second traction stage hot zone temperature T2, outlet hot zone temperature T3, bearing or bearing sensitive area temperature Tb, water cooling status, mechanical temperature control switch status, power commands and actual power feedback for each heating channel, actual output power of the previous control cycle, ambient temperature, and one or more of the following: historical under-temperature, over-temperature, and fault data.

[0022] Operational data can be recorded and updated according to certain rules, such as periodic updates based on a preset control cycle, and data from multiple acquisition times can be retained for data statistics and subsequent analysis tasks.

[0023] Step 120: Based on the operating data, perform anti-deposition heating demand analysis, thermal zone coordination analysis, and safe power analysis independently. Among them, the anti-deposition heating demand analysis determines the required heating power of each heating channel, the thermal zone coordination analysis determines the power correction amount of each heating channel according to the thermal coupling relationship between each thermal zone, and the safe power analysis determines the upper limit of the total heating power of the magnetic levitation molecular pump and the upper limit of the safe heating power of each heating channel.

[0024] In this embodiment, anti-deposition heating demand analysis, thermal zone coordination analysis, and safe power analysis answer different control questions. Anti-deposition heating demand analysis is used to determine "how much heat is desired" for each thermal zone, and its results include at least the required heating power for the corresponding heating channel; thermal zone coordination analysis is used to determine the impact of heat input and temperature relationships between adjacent thermal zones on the power of this channel, and its results are power correction amounts or power redistribution suggestions; safe power analysis is used to determine "the maximum allowable heat output" for the entire unit and each channel, and its results include the total heating power limit and the safe heating power limit for each heating channel.

[0025] The above analyses are independent of each other, meaning that each analysis can be performed based on the same shared operational data, but one analysis does not use the intermediate results output by another analysis in the current control cycle as the object that must be corrected in sequence, nor does it directly modify the results of other analyses.

[0026] Each analysis can be executed in parallel or asynchronously according to different execution cycles, and the results can be stored and retrieved when needed.

[0027] Therefore, each analysis yields corresponding results from three different aspects: heating demand, thermal coupling within the heating zone, and thermal safety. These results are independent of each other during the analysis process but are used uniformly in the subsequent power determination process. Specifically, the required heating power and power correction amount are used to determine the candidate power for each heating channel, while the upper limit of the total heating power and the upper limit of the safe heating power for each heating channel are used to limit the output range of the candidate power.

[0028] Step 130: Determine the candidate power of each heating channel based on the required heating power and power correction amount, and determine the final output power of each heating channel under the constraints of the total heating power limit and the safe heating power limit of each heating channel.

[0029] In this embodiment, a first traction stage hot zone, a second traction stage hot zone, and an outlet hot zone are provided, that is, at least three hot zones. Each hot zone is provided with an independent heating channel, so at least three heating channels are provided.

[0030] Specifically, for the i-th heating channel, the required heating power can be determined first. Power correction obtained from co-analysis with thermal zones Combined, candidate power is obtained. .

[0031] In one embodiment, candidate power can be obtained based on the following method : The power correction can be positive or negative. Positive values ​​are used to increase the recommended power for lagging heat zones, while negative values ​​are used to decrease the recommended power for heat zones that are subject to large adjacent heat inputs or have abnormal temperature difference trends.

[0032] After obtaining the candidate power for each heating channel, the final output power is determined within a feasible range limited by the total heating power limit and the safe heating power limit for the corresponding channel. Specifically, the final output power of any channel shall not exceed its corresponding safe heating power limit, and the sum of the final output powers of all channels shall not exceed the total heating power limit.

[0033] The specific methods for determining the final output power of each heating channel can include direct cutting, priority allocation, projection onto a feasible power set, or constrained optimization calculations.

[0034] Step 140: Control the heating channels corresponding to the first traction stage hot zone, the second traction stage hot zone, and the outlet hot zone to operate according to the final output power.

[0035] After obtaining the final output power, control commands are sent to the execution units corresponding to the first traction stage hot zone, the second traction stage hot zone, and the outlet hot zone, causing the three heating channels to operate according to their respective final output power. During the power execution process, the actual operating power of each heating channel and temperature data such as T1, T2, and T3 can continue to be acquired, and the above data acquisition, analysis, and power determination process is repeated in the next cycle, thus forming a closed loop for the temperature control of the magnetic levitation molecular pump.

[0036] In one embodiment, in addition to the final output power of each heating channel, the water-cooling module can be synchronously controlled according to the thermal state of the magnetic levitation molecular pump, and alarm, channel isolation, or system interlock commands can be output. The water-cooling module is used to cool non-target areas such as bearing-sensitive areas. When water cooling is activated, each heating channel can continue limited heating according to the current thermal safety status, rather than completely stopping operation. In case of a single channel malfunction, the corresponding channel can be isolated while other normal channels remain operational; in case of severe overheating, magnetic levitation malfunction, communication failure, cooling failure, or system-level fault, the power output of each heating channel can be stopped.

[0037] The second embodiment of this application further specifies the temperature control method of the magnetic levitation molecular pump in the first embodiment in a more detailed and specific way. Some or all of the technical features in the second embodiment can be combined with or replaced by the first embodiment, either individually or in combination, to obtain more feasible temperature control methods for the magnetic levitation molecular pump.

[0038] The temperature control method of the magnetic levitation molecular pump in the second embodiment of this application is described in detail below: Optionally, the method further includes: performing channel reliability analysis based on operational data, independently of anti-deposition heating demand analysis, thermal zone coordination analysis, and safe power analysis, wherein the channel reliability analysis determines the channel reliability of each heating channel based on the consistency between the temperature signal, power execution status, and thermal response of each heating channel; and determining the final output power of each heating channel under the constraints of the total heating power limit and the safe heating power limit of each heating channel, including: determining the reliable power limit of the corresponding heating channel based on the channel reliability of each heating channel and the preset power limit of each heating channel, and determining the final output power of each heating channel under the constraints of the total heating power limit, the safe heating power limit of each heating channel, and the reliable power limit.

[0039] This embodiment further introduces independent channel reliability analysis to address the question of whether the calculated power meets the thermal safety boundary, but the corresponding temperature measurement, power execution, or thermal response is still reliable.

[0040] Specifically, the channel reliability analysis is independent of the anti-deposition heating requirement analysis, hot zone synergy analysis, and safe power analysis. The usability of the channel is mainly evaluated based on whether the temperature signal, power command and power feedback of the i-th heating channel, and the temperature rise response of the current hot zone and adjacent hot zones after heating meet the expected relationship.

[0041] In one embodiment, the channel confidence level is denoted as... . Normalize to 0 to 1. The closer the result is to 1, the more reliable the temperature measurement, execution, and thermal response of the i-th heating channel are; When the power is reduced, the range of power distribution that the corresponding channel can participate in shrinks accordingly.

[0042] Let the preset power limit for each channel be... In one embodiment, the reliable power upper limit of the i-th heating channel is determined according to the following method: : The final output power is determined under the combined constraints of the total heating power limit, the safe heating power limit, and the reliable power limit.

[0043] In one embodiment, channel-level licensing can also be configured. When the mechanical over-temperature protection device trips, or when a hard fault such as an open circuit, short circuit, or power device adhesion is confirmed, the system no longer relies solely on continuous reliability scoring, but instead directly... Setting it to 0 directly reduces the reliable power limit of that channel to zero. Channel-level permission reflects whether an individual heating channel is allowed to participate in heating, serving as a last resort in case of problems with individual channels.

[0044] In one embodiment, when a channel-level license is configured... hour, It can also be expressed as: Optionally, the channel reliability analysis includes: performing the following analysis for each hot zone in the magnetically levitated molecular pump: determining the temperature reliability score of the heating channel corresponding to the hot zone based on whether the temperature signal of the hot zone is within a preset effective temperature measurement range and whether the temperature change between adjacent sampling periods exceeds a preset temperature jump threshold; determining the power reliability score of the heating channel corresponding to the hot zone based on the deviation between the power command and the actual heating power feedback; determining the effective temperature rise of the hot zone based on the temperature response of the hot zone and other hot zones that are thermally coupled to the hot zone, and determining the thermal response reliability score of the heating channel corresponding to the hot zone based on the relationship between the effective temperature rise and the preset normal temperature rise under the corresponding power input; and determining the channel reliability of the corresponding heating channel based on the temperature reliability score, power reliability score, and thermal response reliability score.

[0045] This embodiment further defines the specific implementation method of channel reliability analysis.

[0046] Specifically, for the i-th hot zone and its corresponding heating channel, its temperature reliability score is... Used to determine whether the temperature sensor output meets basic physical rationality. When the temperature signal... When the temperature exceeds the sensor's or preset effective temperature measurement range, it can be... Set to 0; when When the temperature is within the effective measurement range, further evaluation can be performed based on the temperature jump between adjacent sampling periods. For example, suppose... This represents the allowed temperature jump within a sampling period. In one embodiment, it is obtained based on the following method: : Where sat(x,u,z) represents the limiting function, which is used to limit the data x to the interval [u,z] by transformation or truncation; This indicates the positive part operation; This represents the temperature signal of the i-th thermal zone during the k-th sampling period.

[0047] When the temperature change between adjacent sampling periods does not exceed hour, It can be set to 1; once this threshold is exceeded, It decreases as the abnormal jump variable increases.

[0048] In one embodiment, The parameters can be determined in advance based on the thermal inertia and sampling period of the magnetic levitation molecular pump under normal heating conditions.

[0049] For the i-th hot zone and its corresponding heating channel, its power reliability score This is used to determine whether the heating channel is outputting the previously determined final output power. Let... To control the output of the channel corresponding to the i-th hot zone to output the power command corresponding to the final output power, This refers to the actual power of the heating channel when executing the aforementioned power command. For permissible instructions—feedback deviations. In one embodiment, power reliability scoring. The method of obtaining it is: The closer the power command is to the actual power, The closer q_P,i is to 1, the lower it becomes when the actual power is significantly insufficient relative to the power command, or when no power command is given but the heating channel is detected to be outputting actual power. This evaluation can help identify situations such as insufficient power execution and abnormal conduction of power devices.

[0050] For the i-th hot zone and its corresponding heating channel, the thermal response reliability score is... This is used to determine whether the actual power input produces a temperature rise that conforms to the basic thermal response law. To reduce misjudgments caused by rapid changes in operating conditions, updates can be made only when the actual power feedback of the corresponding channel is consistently higher than the preset evaluation power, the hot zone is in a state of temperature rise demand, and the operating status of each temperature control structure in the magnetic levitation molecular pump is basically stable within the preset evaluation time window. .

[0051] Within the preset evaluation time window W, determine the effective temperature rise of the i-th thermal zone. In one embodiment, for the i-th hot zone, the effective temperature rise is determined by combining the temperature rise generated by the heating power of this hot zone with the influence of adjacent hot zones calculated according to their thermal coupling relationship. .

[0052] set up The minimum normal temperature rise that a normal heating channel should achieve within a certain power level and evaluation time window can be calculated as follows: When the actual effective temperature rise reaches the minimum normal temperature rise amount The value is 1; when the actual effective temperature rise is insufficient, The corresponding decrease; if there is a continuous actual power input and the temperature rise of this hot zone and its adjacent thermally coupled zones is basically zero, then Close to 0.

[0053] If the current operating data is insufficient for thermal response evaluation, the previous valid data can be retained. .

[0054] It can be determined in advance based on normal prototype testing or factory calibration.

[0055] In one embodiment, the channel reliability of the heating channel corresponding to the i-th hot zone is determined by the minimum value among the aforementioned three scores: Using a minimum value allows for timely reduction of the availability of the corresponding channel when any critical link in temperature acquisition, power execution, or thermal response exhibits significant anomalies. It should be noted that the thermal response reliability score is primarily used to identify channel anomalies that clearly violate basic thermal response laws, while general changes in heating efficiency or thermal performance degradation due to deposition are evaluated by anti-deposition thermal performance analysis to avoid repeated treatment of the same phenomenon by different analytical branches.

[0056] In one embodiment, in addition to continuous scoring, channel reliability analysis can also perform multi-source consistency diagnosis. For example, if there is a power command and power feedback but the local and adjacent hot zones have not effectively heated up for a long time, it can be determined that there is an open circuit risk in the heating rod, cable, or power device; if there is no power command but the temperature of the local hot zone continues to rise or the power feedback is not zero, it can be determined that there is a risk of sticking in the relay or solid-state relay; if the temperature sensor reading changes abruptly but the power, adjacent hot zone, and bearing temperatures do not change accordingly, it can be determined that the reliability of the temperature sensor reading has decreased; when the mechanical temperature control switch is activated, the corresponding channel permission can be directly revoked and automatic recovery can be prohibited until manual inspection or reset.

[0057] Optionally, the anti-deposition heating requirement analysis includes: performing the following analysis for each hot zone in the magnetic levitation molecular pump: obtaining deposition-related data for the hot zone from the operating data, and weighting the deposition-related data based on pre-set weights to obtain the deposition risk value of the hot zone. The deposition-related data includes at least two of the following: cumulative undertemperature data, insufficient heating data, abnormal high duty cycle low heating data, continuous operation data, historical undertemperature data, and historical fault data for the hot zone; obtaining the anti-deposition thermal efficiency index of the hot zone based on the relationship between the temperature rise and heating energy of the hot zone, or based on the relationship between the actual heating rate of the hot zone and the pre-calibrated benchmark heating rate; obtaining the basic target temperature, expected heating rate, basic holding time, and basic priority of the hot zone, and correcting the basic target temperature, basic holding time, and basic priority based on the deposition risk value and the anti-deposition thermal efficiency index to determine the target temperature, holding time, and heating priority of the hot zone; and determining the required heating power of the heating channel corresponding to the hot zone based on the deviation between the target temperature and the current temperature of the hot zone and the expected heating rate.

[0058] In this embodiment, the anti-deposition heating requirement analysis determines the staged temperature control state based on the operation stage of the magnetic levitation molecular pump and the temperature of the three hot zones, and provides the basic target temperature for each hot zone based on different states. Desired heating rate Basic insulation time and basic priority .

[0059] Specifically, the phased temperature control states can include states such as prohibiting heating, prioritizing preheating at the outlet, raising the temperature of the three hot zones, stabilizing the temperature, relieving risks and maintaining the temperature, normal shutdown with phased cooling, and fault degradation. For example, in the priority preheating state at the outlet, the hot zone Z3 at the outlet is prioritized to reach the anti-deposition threshold; in the raising the temperature of the three hot zones, the three hot zones are raised according to the restricted slope; and in the stabilizing the temperature, the target temperature of each hot zone is maintained while continuously identifying deposition risks and thermal efficiency.

[0060] To quantify the risk of deposition, calculations can be performed based on the operating data within a preset sliding time window W to obtain cumulative undertemperature data, insufficient heating data, abnormal data of high duty cycle and low heating, continuous operating data, and historical undertemperature / fault data.

[0061] Specifically, the following data can be obtained directly from the operational data: Let a certain control cycle be... The temperature of the i-th hot zone during this control cycle is The anti-deposition threshold temperature for this hot zone is Actual heating rate It can be represented as: Heating duty cycle (power percentage) is The heating duty cycle represents the normalized heating input of the heating channel corresponding to the i-th hot zone during the k-th sampling period, and its value ranges from 0 to 1. When using on-off power control, the heating duty cycle can be determined by the ratio of the cumulative duration of the heating channel being in the on state within the period to the total duration of the entire period. When using continuous power regulation, the heating duty cycle can be determined by the ratio of the actual heating power or power command of the heating channel to the preset maximum power of that heating channel. Therefore, the heating input under different power control methods can be converted into a heating duty cycle with uniform dimensions to characterize the heating level of the corresponding heating channel.

[0062] In one embodiment, under-temperature cumulative data Insufficient heating data High duty cycle low temperature anomaly data They are represented as follows: in, To statistically analyze the historical range of the above data; I(·) is an indicator function that takes 1 if the condition is true and 0 otherwise; This refers to the duration of a cycle; For a predetermined high duty cycle threshold, The minimum effective heating rate is predetermined.

[0063] This represents the total amount of "insufficient temperature × duration". Insufficient temperature rise data. This characterizes the cumulative extent to which the actual heating rate is lower than the expected heating rate during the heating phase. High duty cycle, low heating anomaly data. This characterizes an abnormal situation where a large amount of power has been applied, but the temperature still cannot rise effectively.

[0064] Continuous running data The duration of continuous operation of the magnetic levitation molecular pump during this startup can be used as a reference. With calibration runtime Confirmed. In one embodiment, continuously running data... Determined in the following manner: Historical low temperature data The temperature can be determined based on the undertemperature conditions during the most recent startups of the magnetic levitation molecular pump.

[0065] Historical fault data can be determined based on the fault conditions of the corresponding heating channels during the most recent startup and operation of the magnetic levitation molecular pump.

[0066] After normalizing the above data, the data is weighted according to preset weights to determine the deposition risk value. In one embodiment, for Insufficient heating data High duty cycle low temperature rise anomaly data Continuous operation data and historical low temperature data After normalization, determine The method is as follows: Where a1 to a5 are the preset weights corresponding to each data point; the subscript norm in each data point indicates that the data has been normalized. The closer the value is to 1, the higher the deposition risk in that hot zone.

[0067] In practical applications, the weights can be calibrated based on the pump type of the magnetic levitation molecular pump, the process gas, and the correlation between different deposition-related data and deposition risk.

[0068] Anti-deposition thermal efficiency index Used to determine whether the input heating energy is effectively converted into a temperature rise in the deposition risk area.

[0069] In one embodiment, the temperature rise of a certain thermal zone within a specified time window W can be used as a reference. The ratio of the heating energy input to the corresponding hot zone determines the anti-deposition thermal efficiency index. The specific calculation method is as follows: in, The heating power of this hot zone within the time window W. To prevent constants with a denominator of zero.

[0070] In another embodiment, the temperature can be determined based on the ratio between the actual heating rate and the reference heating rate under clean or factory-calibrated conditions. .

[0071] In this embodiment, the deposition risk value A higher value indicates a greater risk of deposition; the thermal efficiency index for preventing deposition is [not specified]. A decrease indicates insufficient effective temperature rise under the same or higher power input. According to... and It allows for limited adjustments to the base target temperature, base insulation time, and base priority.

[0072] For example, setting a thermal efficiency benchmark. and according to as well as Determine the target temperature correction amount Including the extension of insulation time and priority correction. Target temperature. It can be obtained in the following way: Similarly, heat preservation time It can be done in the same way, The heating priority is extended as the deposition risk increases or the thermal efficiency decreases; exist The value increases with increasing deposition risk or decreased thermal efficiency. Based on this, the deposition risk value is converted into the heating demand of the hot zone.

[0073] In one embodiment, when the deposition risk value exceeds a preset risk threshold and the anti-deposition thermal efficiency index is lower than a preset thermal efficiency threshold, a risk-clearing insulation state can be entered. In this state, the anti-deposition heating demand analysis can propose a need to increase the target temperature of the corresponding hot zone or extend the insulation time; whether the power can actually be increased is still determined by the boundary formed by the safe power analysis and / or channel reliability analysis. Exiting the risk-clearing insulation state can be determined based on at least two of the following conditions: the hot zone remains above the anti-deposition threshold within a preset time; the anti-deposition thermal efficiency index recovers to a preset percentage above the baseline value; the cumulative under-temperature amount or the abnormal amount of high duty cycle low temperature rise decreases below the recovery threshold; and the temperature difference between the hot zone and the bearing temperature are within a safe range.

[0074] After determining the target temperature and the desired heating rate, the required heating power can be calculated based on the deviation between the target temperature and the current temperature, as well as the desired heating rate. The specific calculation method for the required heating power can employ a pre-calibrated transfer function, PID control, lookup table, or other methods, and can be further limited by the temperature regulation hysteresis range.

[0075] For example, in a continuous power regulation embodiment, the base power demand can be calculated based on the temperature deviation and limited within a preset power range. To reduce temperature sampling noise and frequent on / off cycles caused by thermal inertia, a heating on-time threshold can also be set around the current target temperature. : And setting the heating off threshold : And maintain the heating state of the previous control cycle between the two.

[0076] In one specific embodiment, for a target temperature requirement of 85°C, a hysteresis range can be set to start heating at 84.5°C and stop heating at 85.5°C.

[0077] Optionally, the thermal zone collaborative analysis includes: obtaining a thermal coupling matrix to characterize the thermal coupling relationship between each heating channel and each thermal zone, wherein the element in the i-th row and j-th column of the thermal coupling matrix characterizes the influence of the heating power change of the j-th heating channel on the temperature change of the i-th thermal zone; and performing the following analysis for each thermal zone in the magnetic levitation molecular pump: determining the adjacent heat input generated by other heating channels on the thermal zone based on the thermal coupling matrix and the actual heating power of each heating channel in the previous control cycle; and determining the power correction amount of the heating channel corresponding to the thermal zone based on the adjacent heat input and the temperature relationship between the first traction stage thermal zone, the second traction stage thermal zone and the outlet thermal zone, so as to maintain a preset ordered temperature difference relationship between the first traction stage thermal zone, the second traction stage thermal zone and the outlet thermal zone along the gas discharge direction.

[0078] In this embodiment, the thermal coupling matrix K is used to describe the cross-thermal effects of different heating channels on different hot zones. The rows of the matrix correspond to the affected hot zones, and the columns correspond to the heating channels on which power is applied. This represents the effect of the change in heating power of the j-th heating channel on the temperature change of the i-th hot zone. For example, This indicates the thermal impact of changes in the heating power of the first traction stage heating channel on the hot zone of the second traction stage.

[0079] In one embodiment, the thermal coupling matrix can be obtained through offline power calibration. Specifically, under preset rotational speed, cooling conditions, and environmental conditions, a power step can be applied only to the j-th heating channel. It also records the temperature changes of each hot zone within a preset time period. Or the change in the slope of the temperature rise, based on which to determine .

[0080] In one embodiment, the thermal coupling matrix can be determined and updated online during operation. For example, when the power change of the j-th channel is significantly greater than that of other channels within a certain time window, and the temperature sensor and cooling status are normal, a new estimate is obtained based on the temperature response of each thermal zone within that time window. And based on: Perform recursive updates, where λ is the update coefficient between 0 and 1; [k] represents the k-th running cycle or control cycle.

[0081] To maintain the independence between the thermal zone collaborative analysis and the anti-deposition heating demand analysis, this embodiment predicts adjacent heat inputs based on the actual output power of each heating channel in historical control cycles or power feedback confirmed by measurement, rather than directly reading the required heating power for the current control cycle. For the i-th thermal zone, its adjacent heat inputs can be expressed as: in, This represents the heating power of the j-th heating channel in the previous cycle. When... When the i-th hot zone is large and is still heating in the previous control cycle, a negative power correction can be given to the i-th channel to reduce repeated heating and temperature rise overshoot; when the i-th hot zone is no longer heating in the previous control cycle, zero correction can be maintained or the power of the channel can no longer be reduced.

[0082] In one embodiment, the power correction amount can also be determined or adjusted based on the current temperature relationship of the three hot zones. Specifically, an ordered temperature difference relationship between the hot zones is preset. For example, the three hot zones maintain a restricted and clearly defined ordered temperature difference along the gas discharge direction, i.e., the temperature of the outlet hot zone is not lower than the temperature of the second traction stage hot zone, the temperature of the second traction stage hot zone is not lower than the temperature of the first traction stage hot zone, or T3−T2 and T2−T1 are respectively within a preset small temperature difference range. When the temperature rise of a certain hot zone lags behind, the power correction amount of that hot zone is increased accordingly through hot zone co-analysis; when the temperature of a certain hot zone is too high or it is subjected to a large adjacent heat input, the power correction amount of that hot zone can be reduced or a power redistribution suggestion between channels can be directly given.

[0083] In this embodiment, the above analysis belongs to the soft coordination objective of the collaborative analysis. The rigid requirements of the magnetic levitation molecular pump, such as the maximum allowable temperature, hard temperature difference, bearing overheating and other insurmountable limitations, are determined by the safety power analysis.

[0084] Optionally, the safe power analysis includes: acquiring the temperature of the bearing sensitive area of ​​the magnetically levitated molecular pump, the temperature rise rate of the bearing sensitive area, and the thermal coupling relationship between each hot zone and the bearing sensitive area; determining the coupled heat load generated by each heating channel to the bearing sensitive area based on the thermal coupling relationship between each hot zone and the bearing sensitive area and the actual output power of each heating channel in the previous control cycle; determining the anti-deposition heat budget coefficient based on the temperature of the bearing sensitive area, the temperature rise rate, and the coupled heat load corresponding to each heating channel, and scaling the preset total heating power benchmark value based on the anti-deposition heat budget coefficient to determine the upper limit of the total heating power; and determining the safe heating power upper limit of the heating channel corresponding to each hot zone based on the preset heating power benchmark value of the heating channel corresponding to each hot zone, and at least one of the following data: the relationship between the current temperature of the hot zone and the preset maximum temperature threshold, the relationship between the current temperature difference between each hot zone and the preset temperature difference threshold, and the predicted temperature rise rate of the hot zone.

[0085] This embodiment defines the specific method for determining the upper limit of total heating power and the upper limit of safe heating power for each channel through safe power analysis.

[0086] Specifically, in order to quantify the thermal impact of each heating channel on the bearing sensitive area, the thermal coupling coefficient between the i-th heating zone and the bearing sensitive area can be obtained in advance. And based on the heating power of the previous control cycle Determine the coupled heat load generated by this channel, for example, using express.

[0087] The coupled thermal loads of each channel can be used individually to determine local risks, or they can be normalized and aggregated to form a coupled thermal load risk characterizing the degree of heating in the bearing area. .

[0088] In one embodiment, the temperature risk of the bearing sensitive area, the bearing temperature rise risk, and the coupled thermal load risk are normalized to: , and All three are between 0 and 1, among which Based on the temperature of the bearing sensitive area Sure, Based on bearing temperature rise rate Sure, according to and the actual output power of the previous control cycle Confirmed. The anti-deposition thermal budget coefficient B is expressed as: Where c1, c2, and c3 are pre-set non-negative weighting coefficients, satisfying c1 + c2 + c3 = 1. The anti-deposition heat budget coefficient B represents the proportion of power currently available for anti-deposition heating while ensuring the thermal safety of the bearing's sensitive area. When the temperature of the bearing's sensitive area... Bearing temperature rise rate When the heat load transferred to the sensitive area of ​​the bearing increases, the heat budget coefficient B for preventing heat deposition decreases; when the aforementioned heat risk decreases, B increases.

[0089] set up The preset total heating power reference value is the total heating power allowed for anti-deposition heating under normal thermal conditions, then the upper limit of the total heating power is... It can be determined in the following ways: For the i-th heating channel, the rated power of that channel can be used as the preset heating power reference value, or a heating power reference value can be preset based on other criteria. Based on one or more of the following data: the margin between the current temperature and the maximum allowable temperature of the corresponding hot zone, the margin between the current temperature difference and the hard temperature difference threshold between each hot zone, and the predicted heating rate, the basic safe power limit is corrected by scaling, segmented limiting, or table lookup to obtain the safe heating power limit for the corresponding heating channel of that hot zone. .

[0090] Specifically, when the corresponding hot zone approaches the safety boundary When the temperature drops to the level where further heating is prohibited. It should be zero.

[0091] This allows for the formation of a safe power set. This limits the range of total heating power for all channels and the heating power for each individual channel: The embodiment proposed The total power available for anti-deposition heating of the entire machine is limited, and P_i,safe limits the local safe power that cannot be exceeded in a single hot zone. Both limits are applied simultaneously in the process of determining the final output power of each channel.

[0092] In one embodiment, system-level heating permission can also be determined. Only when heating is permitted during the molecular pump operation phase, the magnetic levitation state is normal, there are no emergency stops or serious system failures, the communication heartbeat is valid, and the cooling capacity meets the requirements, Take 1; in cases of severe overheating, magnetic levitation anomaly, communication failure, cooling failure, or system-level failure, Take 0. When When the value is 0, the maximum total heating power and the maximum safe heating power of each channel can be directly reduced to zero, and heating is prohibited.

[0093] In one embodiment, safe power analysis can also be used to control the start and stop of the water-cooling module. The water cooling can employ hysteresis control using start and stop thresholds. For example, water cooling is activated when the temperature of a certain hot zone, pump bottom, bearing sensitive area, or preset monitoring location is higher than the water cooling start threshold, and deactivated when it is lower than the water cooling stop threshold. In one embodiment, 90°C can be used as the water cooling start threshold and 80°C as the water cooling stop threshold, and a strong power limiting or protection state can be entered when the bearing temperature approaches 95°C.

[0094] It should be noted that activating water cooling does not automatically shut down all heating channels: if a target hot zone experiences overheating, the corresponding channel can be reduced or shut off; if water cooling is activated primarily due to temperature rise in sensitive bearing areas, then, within permissible thermal safety limits, restricted heating can still be maintained for hot zones requiring anti-deposition treatment. The actual cooling effect of water cooling is determined by… and Changes in B are fed back to B, rather than water-cooling related data being considered a direct influencing factor of B.

[0095] Optionally, the anti-deposition heating requirement analysis also determines the heating priority of each heating channel; under the constraints of the total heating power limit, the safe heating power limit and the reliable power limit of each heating channel, the final output power of each heating channel is determined, including: determining the allowable power limit of each heating channel according to the safe heating power limit and the reliable power limit of each heating channel respectively; limiting each candidate power according to the allowable power limit, and if the sum of the limited candidate powers exceeds the total heating power limit, allocating the limited candidate powers within the total heating power limit according to the heating priority of each heating channel to determine the final output power of each heating channel.

[0096] This embodiment further defines the power allocation method for the final output power of each heating channel.

[0097] Specifically, for the i-th heating channel, based on the upper limit of safe heating power... and trusted power limit Determine the upper limit of allowable power In one embodiment, the allowable power limit is determined as follows: : Then, the candidate power obtained from the required heating power and the power correction amount will be... Crop to [0, Within the specified range, the candidate power after limitations is obtained. If the sum of all the candidate power after limitations does not exceed the upper limit of the total heating power P_Σ,safe, then the candidate power after limitations can be used as the final output power, or the power change between adjacent control cycles can be smoothed without exceeding the above upper limit.

[0098] If the sum of the power of each constrained candidate exceeds This indicates that while the local power of each channel is acceptable, the total usable power of the entire unit is insufficient. In this embodiment, the heating priority can be determined based on the analysis of anti-deposition heating requirements. ,exist Within a given range, limited power is redistributed to determine the final output power of each heating channel. For example, higher-priority heating zones are given priority in retaining their required power, and when a channel reaches its limit... Then, the remaining total power is further allocated to other channels that have not yet reached their allowable power limits, ensuring that the total output power does not exceed the limit throughout the allocation process. And each heating channel does not exceed its corresponding Alternatively, in another embodiment, a weighted approach can be used for power redistribution. That is, the corresponding allocation weight is determined according to the heating priority of each heating channel, and the limited power is proportionally allocated within the total heating power limit according to each allocation weight. During the weighting process, when a heating channel reaches its allowable power limit, the remaining power is allocated according to the allocation weight of other heating channels until the total heating power is allocated or each heating channel reaches its corresponding allowable power limit.

[0099] In another alternative embodiment, the allocation process may also take into account channel confidence and remaining security margin, so that channels with lower confidence or smaller security margins are subject to more stringent power limits.

[0100] In this way, the final output power of each heating channel will not exceed the safe power limit or the reliable power limit. When the total power is reduced due to bearing thermal risk, the priority obtained from the demand analysis can still determine which hot zone the limited safe power is preferentially used for, thereby avoiding the simple coverage of anti-deposition requirements by safety restrictions.

[0101] Optionally, the operational data includes operational data of the magnetically levitated molecular pump acquired at multiple acquisition times; anti-deposition heating demand analysis, thermal zone synergy analysis, safety power analysis, and channel reliability analysis respectively acquire operational data related to the corresponding analysis from the operational data, and the acquisition time ranges corresponding to the operational data used in different analyses may be the same or different.

[0102] This embodiment further illustrates that the anti-deposition heating demand analysis, thermal zone coordination analysis, safety power analysis, and / or channel reliability analysis can be executed in parallel or asynchronously according to different update cycles. Parallel execution means that within the same control cycle, each analysis reads the required operating data and completes its calculation independently. Asynchronous execution means that different analyses are updated separately according to their corresponding thermal process change rate, control real-time requirements, or fault response requirements, without requiring all four analyses to be recalculated simultaneously in every control cycle. Therefore, while the analyses are functionally independent, they do not need to form a fixed sequential calling relationship in terms of execution timing.

[0103] To support the aforementioned parallel or asynchronous execution methods, this embodiment proposes that the runtime data can include not only runtime data acquired during the current control cycle or at the most recent acquisition moment, but also historical runtime data acquired and saved at multiple acquisition moments. Each analysis can select data relevant to its own analysis from the shared runtime data, and select the same or different acquisition time ranges based on the time scale of the physical process being analyzed.

[0104] For example, in anti-deposition heating demand analysis, cumulative undertemperature data, insufficient temperature rise data, and the anti-deposition thermal efficiency index are typically used to reflect changes in thermal state over a period of time and can be determined based on data within a relatively long sliding time window. Hot zone coordination analysis can primarily determine adjacent heat inputs and power corrections based on the actual heating power of the previous control cycle and the recent temperature response of each hot zone. Safe power analysis can primarily determine the upper limit of total heating power and the upper limit of safe heating power based on the current temperature of the bearing's sensitive area and the bearing temperature rise rate over a short time range. Temperature jump judgment in channel reliability analysis can use data from adjacent sampling cycles, while thermal response reliability scoring can use power input and temperature response data over a period of time that meets preset evaluation conditions. Therefore, the data used in different analyses can come from the same set of acquisition times or from historical data windows of different lengths or locations.

[0105] Furthermore, the update cycle for each analysis can be set according to the dynamic characteristics of the corresponding analysis object. Typically, safety power analysis and channel reliability analysis involve safety-related states such as over-temperature, abnormal power execution, and channel failure, and can use relatively short update cycles. Anti-deposition heating demand analysis mainly reflects the cumulative changes in deposition risk and thermal efficiency over time, while thermal zone synergy analysis mainly reflects thermal coupling processes with a certain thermal inertia; therefore, relatively long update cycles can be used. In one embodiment, based on the thermal inertia of the magnetically levitated molecular pump, the sensor sampling cycle, and the controller's computing power, the basic control cycle is set to 1 s, and the statistical time window for deposition risk analysis-related data is set to 60 s to 300 s.

[0106] When using asynchronous updates, the results of each analysis can also include validity information such as generation time, validity period, and status code, and be written to the corresponding result cache. For unified power determination, the latest valid analysis results from each analysis can be read, without requiring all results to have exactly the same generation time. Therefore, for example, if the safety power analysis has updated the total heating power limit based on the latest bearing temperature, even if the anti-deposition heating demand analysis still uses the demand heating power obtained from the previous update cycle, the latest safety power limit can be used for final power determination, allowing safety-related analyses to be applied to heating control in a timely manner.

[0107] When an analysis result exceeds its preset validity period, corresponding conservative measures can be taken based on the function of the analysis. For example, if the anti-deposition heating demand analysis result fails, the preset basic heating demand can be reverted; if the thermal zone synergy analysis result fails, the power correction amount can be set to zero or a default correction result based on pre-calibrated thermal coupling relationships can be adopted; if the safe power analysis result fails, the upper limit of total heating power and the safe heating power upper limit of each heating channel can be tightened; if the channel reliability analysis result fails, the reliable power upper limit of the corresponding heating channel can be reduced or the corresponding heating channel can be prohibited from participating in power allocation. Through the above processing, different analyses can be updated independently according to their respective time scales, while avoiding the impact of expired analysis results on the safety of current heating control.

[0108] The third embodiment of this application also proposes a temperature control device for a magnetically levitated molecular pump, such as... Figure 3 As shown, the device includes: Data acquisition unit 310 is used to acquire the operating data of the magnetic levitation molecular pump; The data analysis unit 320 independently performs anti-deposition heating demand analysis, thermal zone coordination analysis, and safe power analysis based on the operating data. The anti-deposition heating demand analysis determines the required heating power of each heating channel. The thermal zone coordination analysis determines the power correction amount of each heating channel based on the thermal coupling relationship between each thermal zone. The safe power analysis determines the upper limit of the total heating power of the magnetic levitation molecular pump and the upper limit of the safe heating power of each heating channel. The power calculation unit 330 is used to determine the candidate power of each of the heating channels based on the required heating power and the power correction amount, and to determine the final output power of each of the heating channels under the constraints of the total heating power limit and the safe heating power limit of each of the heating channels; The control execution unit 340 is used to control the heating channels corresponding to the first traction stage hot zone, the second traction stage hot zone and the outlet hot zone to operate according to the final output power.

[0109] Further functional descriptions of the above modules and units are the same as those in the corresponding embodiments described above, and will not be repeated here.

[0110] In this embodiment, the temperature control device for the magnetic levitation molecular pump is presented in the form of a functional unit. Here, a unit refers to an ASIC (Application Specific Integrated Circuit) circuit, a processor and memory that execute one or more software or fixed programs, and / or other devices that can provide the above functions.

[0111] Please see Figure 4 , Figure 4 This is a schematic diagram of the structure of a computer device provided in the fourth embodiment of this application, as shown below. Figure 4 As shown, the computer device includes one or more processors 410, memory 420, and interfaces for connecting the components, including high-speed interfaces and low-speed interfaces. The components communicate with each other via different buses and can be mounted on a common motherboard or otherwise installed as needed. The processors can process instructions executed within the computer device, including instructions stored in or on memory to display graphical information of a GUI on external input / output devices (such as display devices coupled to the interfaces). In some alternative implementations, multiple processors and / or multiple buses can be used with multiple memories, if desired. Similarly, multiple computer devices can be connected, each providing some of the necessary operations (e.g., as a server array, a group of blade servers, or a multiprocessor system). Figure 4 Take a processor 410 as an example.

[0112] Processor 410 may be a central processing unit, a network processor, or a combination thereof. Processor 410 may further include a hardware chip. The hardware chip may be an application-specific integrated circuit (ASIC), a programmable logic device (PLD), or a combination thereof. The programmable logic device may be a complex programmable logic device (CAMP), a field-programmable gate array (FPGA), a general-purpose array logic (GDA), or any combination thereof.

[0113] The memory 420 stores instructions executable by at least one processor 410 to cause the at least one processor 410 to perform the method shown in the above embodiments.

[0114] The memory 420 may include a program storage area and a data storage area. The program storage area may store the operating system and applications required for at least one function; the data storage area may store data created based on the use of the computer device. Furthermore, the memory 420 may include high-speed random access memory and may also include non-transitory memory, such as at least one disk storage device, flash memory device, or other non-transitory solid-state storage device. In some alternative embodiments, the memory 420 may optionally include memory remotely located relative to the processor 410, and these remote memories may be connected to the computer device via a network. Examples of such networks include, but are not limited to, the Internet, intranets, local area networks, mobile communication networks, and combinations thereof.

[0115] The memory 420 may include volatile memory, such as random access memory; the memory may also include non-volatile memory, such as flash memory, hard disk or solid-state drive; the memory 420 may also include a combination of the above types of memory.

[0116] The computer device also includes a communication interface 430 for communicating with other devices or communication networks.

[0117] This application embodiment also provides a magnetic levitation molecular pump, which is provided with a first traction stage hot zone located at the upper part of the traction stage of the magnetic levitation molecular pump, a second traction stage hot zone located at the lower part of the traction stage, and an outlet hot zone. The first traction stage hot zone, the second traction stage hot zone, and the outlet hot zone are each provided with an independent heating channel. The magnetically levitated molecular pump is also equipped with the computer equipment described in the fourth embodiment.

[0118] This application also provides a computer-readable storage medium. The methods described in this application can be implemented in hardware or firmware, or implemented as recordable on a storage medium, or implemented as computer code downloaded over a network and originally stored on a remote storage medium or a non-transitory machine-readable storage medium and subsequently stored on a local storage medium. Thus, the methods described herein can be processed by software stored on a storage medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware. The storage medium can be a magnetic disk, optical disk, read-only memory, random access memory, flash memory, hard disk, or solid-state drive, etc.; further, the storage medium can also include combinations of the above types of memory. It is understood that computers, processors, microprocessor controllers, or programmable hardware include storage components capable of storing or receiving software or computer code. When the software or computer code is accessed and executed by the computer, processor, or hardware, the methods shown in the above embodiments are implemented.

[0119] This application provides a computer program product including computer instructions stored in a computer-readable storage medium. A processor of a computer device reads the computer instructions from the computer-readable storage medium and executes the computer instructions, causing the computer device to perform the method of any embodiment of this application.

[0120] The methods, apparatus, computer devices, magnetically levitated molecular pumps, computer-readable storage media, and computer program products described in the above embodiments can be implemented by computer chips or entities, or by products with certain functions. A typical implementing device is a computer. Specifically, a computer can be, for example, a personal computer, laptop computer, cellular phone, camera phone, smartphone, personal digital assistant, media player, navigation device, email device, game console, tablet computer, wearable device, or any combination of these devices.

[0121] For ease of description, the above devices are described separately by function as various units. Of course, in implementing this application, the functions of each unit can be implemented in one or more software and / or hardware.

[0122] Those skilled in the art will understand that embodiments of this application can be provided as methods, apparatus, computer devices, magnetically levitated molecular pumps, computer-readable storage media, and computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-readable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-readable program code.

[0123] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus, computer devices, magnetically levitated molecular pumps, computer-readable storage media, and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0124] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0125] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0126] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0127] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to interchangeably. Each embodiment focuses on describing the differences from other embodiments. In particular, the embodiments of apparatus, computer equipment, magnetically levitated molecular pumps, computer-readable storage media, and computer program products are basically similar to the method embodiments, so the descriptions are relatively simple, and relevant parts can be referred to the descriptions of the method embodiments.

[0128] The above description is merely an embodiment of this application and is not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

[0129] Although embodiments of this application have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of this application, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A method for temperature control of a magnetically levitated molecular pump, characterized in that, The magnetically levitated molecular pump is provided with a first traction stage hot zone located at the upper part of the traction stage, a second traction stage hot zone located at the lower part of the traction stage, and an outlet hot zone. The first traction stage hot zone, the second traction stage hot zone, and the outlet hot zone are each provided with an independent heating channel. The method includes: Obtain the operating data of the magnetically levitated molecular pump; Based on the operational data, anti-deposition heating demand analysis, thermal zone coordination analysis, and safe power analysis are performed independently. Specifically, the anti-deposition heating demand analysis determines the required heating power of each heating channel, the thermal zone coordination analysis determines the power correction amount of each heating channel according to the thermal coupling relationship between each thermal zone, and the safe power analysis determines the upper limit of the total heating power of the magnetic levitation molecular pump and the upper limit of the safe heating power of each heating channel. The candidate power of each heating channel is determined based on the required heating power and the power correction amount, and the final output power of each heating channel is determined under the constraints of the total heating power limit and the safe heating power limit of each heating channel. The heating channels corresponding to the first traction stage hot zone, the second traction stage hot zone, and the outlet hot zone are controlled to operate according to the final output power.

2. The temperature control method for a magnetically levitated molecular pump according to claim 1, characterized in that, The method further includes: Based on the operational data, channel reliability analysis is performed independently of the anti-deposition heating demand analysis, the thermal zone coordination analysis, and the safety power analysis. The channel reliability analysis determines the channel reliability of each heating channel based on the consistency between the temperature signal, power execution status, and thermal response of each heating channel. Determining the final output power of each heating channel under the constraints of the total heating power limit and the safe heating power limit of each heating channel includes: Based on the channel reliability of each heating channel and the preset power limit of each heating channel, the reliable power limit of the corresponding heating channel is determined, and under the constraints of the total heating power limit, the safe heating power limit of each heating channel and the reliable power limit, the final output power of each heating channel is determined.

3. The method according to claim 2, characterized in that, The channel reliability analysis includes: The following analysis is performed on each of the hot zones in the magnetically levitated molecular pump: Based on whether the temperature signal of the hot zone is within a preset effective temperature measurement range and whether the temperature change between adjacent sampling periods exceeds a preset temperature jump threshold, the temperature reliability score of the heating channel corresponding to the hot zone is determined. Based on the deviation between the power command and the actual heating power feedback of the heating channel corresponding to the hot zone, a power reliability score for the heating channel corresponding to the hot zone is determined. Based on the temperature response of the hot zone and other hot zones that are thermally coupled with the hot zone, the effective temperature rise of the hot zone is determined, and based on the relationship between the effective temperature rise and the preset normal temperature rise under the corresponding power input, the thermal response reliability score of the heating channel corresponding to the hot zone is determined. The channel confidence level of the corresponding heating channel is determined based on the temperature confidence score, the power confidence score, and the thermal response confidence score.

4. The temperature control method for a magnetically levitated molecular pump according to claim 1, characterized in that, The analysis of the anti-deposition heating requirements includes: The following analysis is performed on each of the hot zones in the magnetically levitated molecular pump: Deposition-related data of the hot zone is obtained from the operational data, and the deposition-related data is weighted according to a pre-set weight to obtain the deposition risk value of the hot zone. The deposition-related data includes at least two of the following: cumulative undertemperature data, insufficient heating data, high duty cycle low heating anomaly data, continuous operation data, historical undertemperature data, and historical fault data of the hot zone. The anti-deposition thermal efficiency index of the hot zone is obtained based on the relationship between the temperature rise of the hot zone and the heating energy, or based on the relationship between the actual heating rate of the hot zone and the pre-calibrated reference heating rate. The basic target temperature, expected heating rate, basic heat preservation time, and basic priority of the hot zone are obtained, and the basic target temperature, basic heat preservation time, and basic priority are corrected according to the deposition risk value and the anti-deposition thermal efficiency index to determine the target temperature, heat preservation time, and heating priority of the hot zone. The required heating power of the heating channel corresponding to the hot zone is determined based on the deviation between the target temperature and the current temperature of the hot zone and the expected heating rate.

5. The method according to claim 1, characterized in that, The thermal zone co-analysis includes: Obtain a thermal coupling matrix to characterize the thermal coupling relationship between each of the heating channels and each of the hot zones, wherein the element in the i-th row and j-th column of the thermal coupling matrix characterizes the effect of the heating power change of the j-th heating channel on the temperature change of the i-th hot zone; The following analysis is performed on each of the hot zones in the magnetically levitated molecular pump: Based on the thermal coupling matrix and the actual heating power of each heating channel in the previous control cycle, determine the adjacent heat input generated by the other heating channels to the hot zone; Based on the adjacent heat inputs and the temperature relationships between the first traction stage hot zone, the second traction stage hot zone, and the outlet hot zone, the power correction amount of the heating channel corresponding to the hot zone is determined so that the first traction stage hot zone, the second traction stage hot zone, and the outlet hot zone maintain a preset ordered temperature difference relationship along the gas discharge direction.

6. The method according to claim 1, characterized in that, The secure power analysis includes: The temperature of the bearing sensitive area of ​​the magnetic levitation molecular pump, the temperature rise rate of the bearing sensitive area, and the thermal coupling relationship between each of the hot zones and the bearing sensitive area are obtained. Based on the thermal coupling relationship between each of the hot zones and the bearing sensitive area, and the actual output power of each of the heating channels in the previous control cycle, the coupled thermal load generated by each of the heating channels to the bearing sensitive area is determined. Based on the temperature of the bearing sensitive area, the temperature rise rate, and the coupled heat load corresponding to each heating channel, an anti-deposition heat budget coefficient is determined, and the preset total heating power benchmark value is scaled according to the anti-deposition heat budget coefficient to determine the upper limit of the total heating power. Based on the preset heating power benchmark value of the heating channel corresponding to each of the hot zones, and according to at least one of the following data: the relationship between the current temperature of the hot zone and the preset maximum temperature threshold, the relationship between the current temperature difference between each of the hot zones and the preset temperature difference threshold, and the predicted heating rate of the hot zones, the safe heating power upper limit of the heating channel corresponding to each of the hot zones is determined.

7. The method according to claim 2, characterized in that, The anti-deposition heating requirement analysis also determines the heating priority of each of the heating channels; Determining the final output power of each heating channel under the constraints of the total heating power limit, the safe heating power limit for each heating channel, and the reliable power limit includes: The permissible power limit of each heating channel is determined based on the safe heating power limit and the reliable power limit of each heating channel. The candidate power is limited according to the allowed power limit. If the sum of the limited candidate power exceeds the total heating power limit, the limited candidate power is allocated within the total heating power limit according to the heating priority of each heating channel to determine the final output power of each heating channel.

8. The method according to claim 2, characterized in that, The operational data includes operational data of the magnetically levitated molecular pump acquired at multiple acquisition times; The anti-deposition heating demand analysis, the thermal zone coordination analysis, the safe power analysis, and the channel reliability analysis each obtain operational data related to the corresponding analysis from the operational data. The acquisition time ranges corresponding to the operational data used in different analyses may be the same or different.

9. A computer device, characterized in that, include: A memory and a processor are communicatively connected, the memory stores computer instructions, and the processor executes the computer instructions to perform the magnetic levitation molecular pump temperature control method according to any one of claims 1 to 8.

10. A magnetically levitated molecular pump, characterized in that, The magnetic levitation molecular pump is provided with a first traction stage hot zone located at the upper part of the traction stage, a second traction stage hot zone located at the lower part of the traction stage, and an outlet hot zone. The first traction stage hot zone, the second traction stage hot zone, and the outlet hot zone are each provided with an independent heating channel. The magnetically levitated molecular pump is also equipped with the computer device described in claim 9.

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