Phase change cooling system for punching machine and control method of phase change cooling system

Abstract

The invention discloses a phase change cooling system for a punching machine and a control method of the phase change cooling system, and relates to the technical field of intelligent temperature control of punching equipment. The phase change cooling system comprises a cooling pipeline module, and the cooling pipeline module comprises a dynamic micro-channel pipeline and a static main pipeline. The dynamic micro-channel pipeline is embedded into the upper die, the lower die and the guide column; the static main pipeline is fixed on a punching machine rack and is independent of a mold moving part; the dynamic micro-channel pipeline is connected with the static main pipeline through a floating quick release interface; and the compression and condensation module drives a phase change medium to circulate in the cooling path module to realize phase change cooling based on the compression and condensation module. Water cooling is replaced by the phase change medium, and the cooling efficiency is improved; a cooling system is independent of a die moving part, the weight of the upper die is prevented from being increased, and equipment stability during stamping is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of intelligent temperature control of stamping equipment, and in particular to a phase change cooling system for a punch press and a control method thereof. BACKGROUND

[0002] In the field of precision stamping processing, a large amount of heat is generated due to friction and plastic deformation during the high-speed continuous work of the die and punch, resulting in a sharp rise in temperature. High temperature not only reduces the hardness of the die and accelerates wear, but also causes thermal expansion deformation, which seriously affects the stamping precision and part quality.

[0003] For example, patent CN117798247A (an automatic punch press with a punch cooling structure) adopts a "water cooling + air cooling" dual mode. Although it realizes pump-free cooling liquid circulation through mechanical linkage, the water cooling heat exchange efficiency is limited, the air cooling heat dissipation contact surface is incomplete, and it is difficult to meet the requirements of high-precision punch press on temperature control precision. In addition, the cooling mechanism is integrated in the upper die, which increases the weight and complexity of the moving parts, and is prone to vibration problems during high-speed stamping, reducing the reliability of the equipment. SUMMARY

[0004] To solve the above problems, the present application provides a phase change cooling system for a punch press, which replaces water cooling with phase change medium to improve cooling efficiency. The cooling system is independent of the die moving parts, avoiding increasing the weight of the upper die and improving the stability of the equipment during stamping. A corresponding control method is provided, which can be applied to the phase change cooling system for the punch press.

[0005] The first technical solution adopted by the present application is to provide a phase change cooling system for a punch press, comprising: A cooling pipeline module, the cooling pipeline module comprises a dynamic micro-channel pipeline and a static main pipeline; the dynamic micro-channel pipeline is embedded inside the upper die, the lower die and the guide column; the static main pipeline is fixed to the punch press frame and is independent of the die moving parts; the dynamic micro-channel pipeline is connected with the static main pipeline through a floating quick-release interface; A compression condensation module, based on which the phase change medium is driven to circulate in the cooling pipeline module to realize phase change cooling.

[0006] In an optional embodiment, the dynamic micro-channel pipeline comprises spiral channels distributed in the upper die punch blade edge region, mesh channels in the lower die forming region, and axial channels on the friction surface of the guide column.

[0007] In an optional embodiment, the compression condensation module drives the phase change medium to realize phase change cooling, which includes compression, condensation, expansion and evaporation stages. Compression stage: low-pressure superheated steam generated in the dynamic micro-channel pipeline is sucked in and output as high-pressure high-temperature gas-phase medium after compression; Condensing stage: the high-pressure high-temperature gas-phase medium flows through the air-cooled condenser to release sensible heat and is converted into high-pressure supercooled liquid; Expansion stage: the high-pressure supercooled liquid is depressurized by the expansion valve to generate a low-temperature low-pressure gas-liquid two-phase flow; Evaporation stage: the low-temperature low-pressure gas-liquid two-phase flow enters the dynamic micro-channel pipeline to absorb the heat of the mold and realize the conversion of the liquid phase to the gas phase.

[0008] In an optional embodiment, the condensing stage further comprises a secondary condensing stage; Part of the high-pressure supercooled liquid flows through the hot end of the thermoelectric generator module; the cold end of the thermoelectric generator module is connected with the secondary cooling circuit; The hot end and the cold end of the thermoelectric generator module form a stable temperature difference to generate electricity; the output end of the thermoelectric generator module is connected with the electric energy management circuit, and the stabilized voltage is supplied to the system load or stored.

[0009] In an optional embodiment, a temperature sensor assembly and a control module are further included; the temperature data of the upper mold, the lower mold and the guide column are obtained based on the temperature sensor assembly; the control module outputs the valve opening degree instruction based on the obtained temperature data.

[0010] In an optional embodiment, the control module comprises a real-time control layer and a prediction correction layer; The real-time control layer adopts a proportional-integral-derivative controller to output the valve opening degree instruction based on the deviation between the set value and the measured temperature in the first period; The prediction correction layer adopts a space-time prediction model to predict the mold temperature change trend in the second period, and dynamically optimizes the temperature set value of the real-time control layer based on the prediction result; When it is detected that the space-time prediction model is invalid, the system automatically switches to a pure feedback control mode, and only the valve opening degree instruction output by the real-time control layer.

[0011] In an optional embodiment, the input of the space-time prediction model comprises a historical temperature sequence, process parameters and frequency domain decomposition features of the temperature signal; The output of the space-time prediction model is used to adaptively adjust the differential term coefficient and the integral term coefficient of the proportional-integral-derivative controller.

[0012] In an optional embodiment, a process adaptive module is further included; the process adaptive module adjusts the cooling strategy based on the material type, the stamping speed and the material thickness.

[0013] The second technical solution adopted in the present application is to provide a control method applied to the phase change cooling system according to any one of the above, comprising: The space-time prediction model of the prediction correction layer periodically outputs the mold temperature change trend; Based on the temperature change trend, the temperature set value of the real-time control layer is dynamically adjusted; In the real-time control layer, based on the deviation between the adjusted temperature set value and the measured temperature, the valve opening control amount of the cooling medium circulation loop is calculated and output.

[0014] In an optional embodiment, it also includes: When a sudden change in process parameters is detected, the frequency domain features of the current temperature signal are extracted; According to the strength of the extracted frequency domain features, the differential action or integral action of the proportional-integral-derivative controller in the real-time control layer is enhanced.

[0015] The present application has the following at least one beneficial effect compared with the prior art by adopting the above technical solutions:

[0016] 1. The cooling system is independent of the mold moving parts, avoiding increasing the weight of the upper mold and improving the stability of the equipment during stamping.

[0017] 2. The cooling efficiency is improved by replacing water cooling with phase change medium.

[0018] 3. Through intelligent control means such as temperature sensor assembly, control module, and prediction correction layer, the cooling parameters can be automatically adjusted according to the actual temperature distribution of the mold, realizing precise dynamic closed-loop control.

[0019] 4. A secondary condensation stage is introduced in the compression condensation module, and a thermoelectric generator module (TEG) is used to recover waste heat and convert it into electrical energy, improving energy utilization efficiency. BRIEF DESCRIPTION OF DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings needed in the embodiment description. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor. Among them: Figure 1 The frame schematic diagram of the phase change cooling system for the punch provided by an embodiment of the present application; Figure 2 The frame schematic diagram of the phase change cooling system for the punch provided by another embodiment of the present application; Figure 3 The frame schematic diagram of the control module in the present application; Figure 2 The frame schematic diagram of the control module in the present application; Figure 4 The control logic schematic diagram of the control module in the present application; Figure 2 The control logic schematic diagram of the control module in the present application; Figure 5 The flowchart schematic diagram of the control method provided by an embodiment of the present application. DETAILED DESCRIPTION

[0021] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. It will be understood that the specific embodiments described herein are only used to explain the present application, rather than to limit the present application. It should also be noted that, for ease of description, only some, rather than all, structures related to the present application are shown in the drawings. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0022] The terms "first," "second," and the like in this application are used to distinguish between different objects, not to describe a particular order. Furthermore, the terms "including," "having," and any variations thereof, are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or apparatus comprising a series of steps or elements is not limited to the listed steps or elements, but may optionally include steps or elements not listed, or may optionally include other steps or elements inherent to the process, method, product, or apparatus.

[0023] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0024] The existing technology has significant drawbacks in the cooling of high-precision punching machines, mainly manifested in low cooling efficiency, the integrated cooling mechanism increases the weight of the upper mold, resulting in increased vibration during high-speed stamping, the lack of intelligent temperature control means making it difficult to respond to mold temperature changes in real time, and high energy consumption and insufficient recycling; in view of this, the present application provides a phase change cooling system for a punching machine, which replaces water cooling with a phase change medium to improve cooling efficiency; the cooling system is independent of the moving parts of the mold to avoid increasing the weight of the upper mold and improve the stability of the equipment during stamping.

[0025] The phase change cooling system for a punching machine provided in this application is suitable for the stamping process of square battery shells for new energy vehicles; the battery shell material is aluminum alloy or stainless steel, and the local temperature of the mold can reach 200-300°C during stamping. The working temperature needs to be controlled below 80-120°C to ensure dimensional accuracy and surface quality.

[0026] like Figure 1 As shown, Figure 1 A schematic diagram of a phase change cooling system for a punch press according to an embodiment of the present application includes: The cooling pipeline module comprises a dynamic micro-channel pipeline and a static main pipeline; the dynamic micro-channel pipeline is embedded inside the upper die, the lower die and the guide column; the dynamic micro-channel pipeline comprises spiral channels distributed in the upper die punch blade edge area, which ensures that the cooling medium can directly contact the high-temperature area and quickly absorb heat, effectively reducing the temperature of the punch.

[0027] The mesh channel of the lower die forming area, the application of the mesh channel in the lower die forming area helps to achieve more uniform cooling effect, avoids the local overcooling or overheating phenomenon that may be caused by the traditional cooling method, and improves the dimensional accuracy of the product.

[0028] The axial channel of the guide column friction surface, the design of the axial channel effectively manages the friction heat generated by long-time high-speed movement, reduces the material expansion or wear caused by temperature rise, and prolongs the service life of the guide column.

[0029] In this embodiment, the upper die punch blade edge is integrally formed with 36 spiral micro-channels at the rear 5mm by 3D printing technology, the channel cross section is semicircular, the depth is 3mm, and the spacing is 2mm. The lower die forming area is formed by electric spark machining and nickel plating treatment, and the mesh micro-channel is arranged at the lower 2mm, the channel width is 2mm, the depth is 3mm, and the node spacing is 3mm. The guide column friction surface is processed by deep hole drilling and polishing treatment, and 8 axial straight channels are evenly distributed along the circumference, the channel diameter is 2mm, and the distance from the surface is 3mm.

[0030] In other embodiments, the material, width, spacing and number of the dynamic micro-channel pipeline can be additionally selected, and no limitation is made thereto.

[0031] The static main pipeline is fixed to the punch machine frame and is independent of the die moving parts; the design of the static main pipeline independent of the die moving parts avoids increasing the mass of the upper die, reduces the vibration problem that may occur during high-speed stamping, and improves the overall stability and reliability of the equipment.

[0032] The dynamic micro-channel pipeline and the static main pipeline are connected through a floating quick-release interface; the design of the floating quick-release interface simplifies the die replacement process, and the operator can quickly disconnect or reconnect the cooling system, shortening the downtime and improving the production efficiency.

[0033] The compression condensation module is based on the compression condensation module to drive the phase change medium to circulate in the cooling pipeline module to realize phase change cooling; in this embodiment, Freon (R134a) is selected as the cooling medium; in other embodiments, propane, isobutane or hydrofluoroolefin can be selected, and no limitation is made thereto.

[0034] The phase change medium boiling point is matched with the process requirement by adjusting the pressure of the variable frequency compressor. The micro channel is arranged inside the mold to directly cool the high temperature area, so that the punch blade temperature is controlled below 100℃, the concave die forming surface is below 90℃, and the guide column friction surface is below 80℃. The compressed condensing module drives the phase change medium to realize the phase change cooling, including compression, condensation, expansion and evaporation stages. The compression, condensation, expansion and evaporation stages are described in detail as follows: Compression stage: the low pressure superheated steam generated by the dynamic micro channel pipeline is compressed and output as high pressure high temperature gas phase medium; that is, the low pressure superheated steam generated by the dynamic micro channel pipeline is sucked into the variable frequency scroll compressor. The compressor can adjust the power according to the actual requirement, so as to compress the low pressure superheated steam into high pressure high temperature gas phase medium.

[0035] Condensation stage: the high pressure high temperature gas phase medium flows through the air-cooled condenser to release sensible heat and is converted into high pressure supercooled liquid. Expansion stage: the high pressure supercooled liquid is decompressed by the expansion valve to generate low temperature low pressure gas-liquid two-phase flow; that is, the high pressure supercooled liquid after condensation is decompressed by the expansion valve to generate low temperature low pressure gas-liquid two-phase flow; the accurate control of the expansion valve ensures that the medium entering the evaporation stage is in the best state to maximize the absorption of mold heat.

[0036] Evaporation stage: the low temperature low pressure gas-liquid two-phase flow enters the dynamic micro channel pipeline to absorb the mold heat and realize the conversion of liquid phase to gas phase; the low temperature low pressure gas-liquid two-phase flow enters the dynamic micro channel pipeline to directly contact the key parts such as the upper die, the lower die and the guide column; the medium rapidly absorbs the heat emitted by the mold and changes from liquid state to gas state, completing a complete phase change cooling cycle.

[0037] The condensation stage also includes a secondary condensation stage; when the primary condensation is not enough to cool the high pressure gas phase medium to the required supercooled liquid state, the secondary condensation can provide additional cooling capacity; the implementation process of the secondary condensation is described in detail as follows: Part of the high pressure supercooled liquid flows through the hot end of the thermoelectric generator module; the cold end of the thermoelectric generator module is connected with the secondary cooling circuit; that is, the high pressure supercooled liquid first flows through the hot end of the thermoelectric generator module (TEG), which is made of In this embodiment, the TEG module is made of base material and contains 16 pairs of series-connected thermocouples with a size of 40×40×5mm. At a working temperature of 80-120℃, the maximum output power can reach 15W.

[0038] The stable temperature difference between the hot end and the cold end of the thermoelectric generator module realizes power generation; the output end of the thermoelectric generator module is connected with the electric energy management circuit, which supplies the system load or stores after voltage stabilization; the electric energy generated by the TEG module is converted by DC-DC conversion and stabilized to 12V, and then preferentially supplied to the sensor network of the system, and the remaining electric energy is stored in the super capacitor for subsequent use.

[0039] After passing through the TEG module, the high-pressure supercooled liquid continues to flow to the secondary cooling circuit, and is further cooled to the ambient temperature through liquid cooling, completing the secondary condensation process; secondary condensation not only ensures that the cooling medium can reach the optimal physical state, but also realizes the effective recovery and reuse of energy, thereby improving energy utilization efficiency.

[0040] like Figure 2 As shown, Figure 2 A framework schematic diagram of a phase change cooling system for a punch press provided in another embodiment of the present application also includes a temperature sensor assembly and a control module; temperature data of the upper die, lower die and guide post are obtained based on the temperature sensor assembly; in this embodiment, three infrared thermocouples spaced 120° apart are arranged on the punch cutting edge to obtain temperature data of the upper die, two optical fiber sensors 10 mm away from the edge are arranged on the forming surface of the die to obtain temperature data of the lower die, and two PT100 platinum resistors are arranged on each guide post to obtain temperature data of the guide post.

[0041] Through high-precision temperature sensors distributed in different parts of the mold, the actual temperature data of the upper mold, lower mold and guide column can be accurately obtained.

[0042] The control module outputs the valve opening instruction based on the acquired temperature data; Figure 3 As shown, Figure 3 for Figure 2 Schematic diagram of the control module framework; the control module consists of a control execution unit, a data acquisition unit, and an edge computing unit.

[0043] The data acquisition unit is responsible for collecting data from various temperature sensors and transmitting this information to the edge computing unit.

[0044] The edge computing unit runs a spatiotemporal prediction model and a PID (proportional-integral-derivative) control algorithm to process this data and outputs valve opening instructions based on the analysis results.

[0045] The control execution unit receives the valve opening instruction to adjust the opening and closing degree of the valve.

[0046] The control module includes a real-time control layer and a prediction and correction layer. That is, the edge computing unit performs calculations based on the real-time control layer and the prediction and correction layer. The following describes the workflow of the control module in detail: The real-time control layer uses a proportional-integral-differential controller, which outputs a valve opening instruction based on the deviation between the set value and the measured temperature in the first cycle. In this embodiment, the real-time control layer directly controls the opening of the electronic expansion valve with a first cycle of 10ms. The input of the proportional-integral-differential controller is the difference between the temperature set value and the current temperature, and the output is the valve opening adjustment amount. The PID control algorithm is as follows: .

[0047] wherein, is the difference between the temperature setpoint and the current temperature, , and are the proportional, integral and derivative gain coefficients, respectively; in the present embodiment, ; in other embodiments, the values of the proportional, integral and derivative gain coefficients can be selected otherwise, without any limitation.

[0048] The prediction correction layer employs a spatio-temporal prediction model, in the present embodiment, the spatio-temporal prediction model employs STC-LSTM (spatio-temporal convolutional long short-term memory network) to realize prediction; the mold temperature variation trend is predicted in the second cycle, and the temperature setpoint of the real-time control layer is dynamically optimized based on the prediction result. In the present embodiment, the second cycle is 1 s, i.e., the prediction is performed once every second.

[0049] The input of the spatio-temporal prediction model includes the historical temperature sequence, the process parameters and the frequency domain decomposition features of the temperature signal; the spatio-temporal prediction model receives the historical temperature sequence, the process parameters and the frequency domain decomposition features of the temperature signal as input, and outputs the temperature prediction value in the next 5 seconds; the working process of the spatio-temporal prediction model in the present embodiment is described in detail as follows: The temperature and process data of the last 20 time steps (a total of 18 dimensions x 20 = 360 input points) are received.

[0050] The input signal is decomposed into high-frequency and low-frequency components by using Haar wavelet.

[0051] Three groups of causal convolution kernels with expansion rates are set to extract multi-scale features; in the present embodiment, the three groups of expansion rates are 1, 2 and 4, respectively.

[0052] The cell state is updated through the gating mechanism, and the temperature prediction value in the next 5 seconds is finally output.

[0053] When it is detected that the spatio-temporal prediction model is invalid, the system automatically switches to a pure feedback control mode, and only the valve opening degree instruction is output by the real-time control layer; in order to prevent excessive regulation from causing system instability, a hardware limit of the valve opening degree is set (for example, the valve opening degree is limited between 20% and 90%); even in the case of invalid spatio-temporal prediction model, the system can still rely on the PID controller to maintain basic temperature control function, avoiding production interruption caused by prediction model failure.

[0054] As shown in Figure 4 , Fig. 4 is a control logic diagram of the control module in Figure 4 . Figure 2

[0055] ​The set value optimizer dynamically calculates the formula according to the prediction result as follows: .

[0056] Wherein, is the process reference temperature, is the safety threshold temperature, can be adaptively adjusted.

[0057] The output of the spatio-temporal prediction model is used to adaptively adjust the derivative term coefficient and the integral term coefficient of the proportional-integral-derivative controller; if the prediction result shows that a rapid temperature rise is about to occur, the derivative term coefficient can be increased to enhance the response speed of the system; if a sustained temperature deviation is expected, the integral term coefficient can be increased to eliminate the steady-state error.

[0058] The PID controller calculates a new valve opening instruction according to the adjusted parameters and sends it to the electric regulating valve for execution; the system periodically (e.g., every 30 minutes) performs incremental learning on the spatio-temporal prediction model based on the latest collected data to ensure that it can accurately reflect the latest changes in working conditions, and simultaneously adjusts the PID parameters in the opposite direction to optimize the control effect.

[0059] The control logic is described in detail below in conjunction with a specific embodiment: in this embodiment, the stamping speed suddenly increases from 60 times / minute to 80 times / minute, and the process parameter change of the first detection of the stamping speed increase.

[0060] The sudden high-frequency component of the temperature signal is captured through wavelet decomposition.

[0061] Output prediction: will rise from 98℃ to 112℃; is the temperature prediction value for the next 5 seconds.

[0062] Calculate the new temperature set value: .

[0063] In this embodiment, the process reference temperature is 100℃, and the safety temperature is 120℃; the set value is lowered in advance to reserve a buffer space for the upcoming temperature rise.

[0064] Adjust the valve opening based on PID, and detect the current temperature as 98℃; calculate the control amount: .

[0065] It can be seen that the valve opening needs to be increased by 15% to strengthen cooling in advance.

[0066] In an embodiment, the phase change cooling system further comprises a process adaptive module (not shown in the figure); the process adaptive module adjusts the cooling strategy based on the material type, the punching speed and the material thickness; based on the input process parameters, the process adaptive module automatically matches the optimal cooling mode and dynamically adjusts the cooling strategy. For example, for thicker materials or higher punching speeds, the system can increase the cooling medium flow or lower the set temperature to ensure that the mold is kept within the ideal temperature range.

[0067] By customizing the adjustment of the cooling strategy for different material properties and processing conditions, the mold temperature can be more accurately controlled, and the product size accuracy can be improved; the process adaptive module can quickly respond to changes in process parameters, without the need for frequent manual adjustment of cooling settings, reducing downtime and improving the overall efficiency of the production line.

[0068] As shown in Figure 5 , Figure 5 The flowchart of the control method provided by an embodiment of the present application, the control method can be applied to the phase change cooling system for a punch as in any of the above embodiments, comprising the following steps:

[0069] S11: periodically output the mold temperature change trend through the time and space prediction model of the prediction correction layer.

[0070] S12: based on the temperature change trend, dynamically adjust the temperature set value of the real-time control layer.

[0071] S13: in the real-time control layer, based on the deviation between the adjusted temperature set value and the measured temperature, calculate and output the valve opening degree control amount of the cooling medium circulation loop.

[0072] The control method further comprises: when a sudden change in process parameters is detected, extracting the frequency domain features of the current temperature signal; According to the strength of the extracted frequency domain features, the differential action or integral action of the proportional-integral-derivative controller in the real-time control layer is enhanced.

[0073] In several embodiments provided by the present application, it should be understood that the disclosed methods and devices can be implemented in other ways. For example, the device embodiments described above are only schematic, for example, the division of the modules or units is only a logical function division, and actual implementation can have another division manner, for example, a plurality of units or components can be combined or integrated into another system, or some features can be ignored or not executed.

[0074] The units described as separate components may or may not be physically separate, and the components displayed as units may or may not be physical units, that is, may be located in one place, or may be distributed on multiple network units. Part or all of the units can be selected according to actual needs to achieve the purpose of the present embodiment scheme.

[0075] In addition, each functional unit in each embodiment of the present application can be integrated into one processing unit, or each unit can exist physically alone, or two or more units can be integrated into one unit. The integrated unit can be realized in the form of hardware or in the form of a software functional unit.

[0076] The above is only an embodiment of the present application, and does not limit the patent scope of the present application, and any equivalent structure or equivalent flow transformation using the content of the present application specification and drawings, or direct or indirect application in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A phase change cooling system for a punch press, characterized in that: include: A cooling pipe module, comprising a dynamic microchannel pipe and a static main pipe; the dynamic microchannel pipe is embedded in the upper die, lower die, and guide column; the static main pipe is fixed to the punch press frame and is independent of the mold moving parts; the dynamic microchannel pipe and the static main pipe are connected via a floating quick-release interface; The compression condensation module drives the phase change medium to circulate in the cooling pipe module to achieve phase change cooling.

2. The phase change cooling system for a punch press according to claim 1, characterized in that: The dynamic microchannel pipeline includes a spiral channel distributed in the cutting edge area of ​​the upper die punch, a mesh channel in the forming area of ​​the lower die, and an axial channel on the friction surface of the guide column.

3. The phase change cooling system for a punch press according to claim 1, characterized in that: The compression condensation module drives the phase change medium to achieve phase change cooling including compression, condensation, expansion and evaporation stages; Compression stage: The low-pressure superheated steam generated by the dynamic microchannel pipeline is sucked in and compressed to output as a high-pressure and high-temperature gaseous medium; Condensation stage: The high-pressure and high-temperature gaseous medium flows through the air-cooled condenser to release sensible heat and is converted into a high-pressure subcooled liquid; Expansion stage: The high-pressure subcooled liquid is depressurized by the expansion valve to generate a low-temperature and low-pressure gas-liquid two-phase flow; Evaporation stage: Low-temperature and low-pressure gas-liquid two-phase flow enters the dynamic microchannel pipeline, absorbs the heat of the mold and realizes the transformation from liquid phase to gas phase.

4. The phase change cooling system for a punch press according to claim 3, characterized in that: The condensation stage also includes a secondary condensation stage; Part of the high-pressure supercooled liquid flows through the hot end of the thermoelectric power generation module; the cold end of the thermoelectric power generation module is connected to the secondary cooling circuit; The hot end and the cold end of the thermoelectric power generation module form a stable temperature difference to achieve power generation; the output end of the thermoelectric power generation module is connected to the power management circuit and supplies the system load or storage after voltage stabilization.

5. The phase change cooling system for a punch press according to claim 1, characterized in that: It also includes a temperature sensor component and a control module; based on the temperature sensor component, temperature data of the upper mold, the lower mold and the guide column are obtained; and the control module outputs a valve opening instruction based on the obtained temperature data.

6. The phase change cooling system for a punch press according to claim 5, characterized in that: The control module includes a real-time control layer and a prediction and correction layer; The real-time control layer adopts a proportional-integral-differential controller to output a valve opening instruction based on the deviation between the set value and the measured temperature in the first cycle; The prediction and correction layer uses a spatiotemporal prediction model to predict the mold temperature change trend in the second period, and dynamically optimizes the temperature setting value of the real-time control layer based on the prediction result; When it is detected that the spatiotemporal prediction model fails, the system automatically switches to a pure feedback control mode, and only the real-time control layer outputs the valve opening instruction.

7. The phase change cooling system for a punch press according to claim 6, characterized in that: The input of the spatiotemporal prediction model includes historical temperature series, process parameters and frequency domain decomposition characteristics of temperature signals; The output of the spatiotemporal prediction model is used to adaptively adjust the differential term coefficient and the integral term coefficient of the proportional-integral-derivative controller.

8. The phase change cooling system for a high-precision punch press according to claim 1, characterized in that: It also includes a process adaptation module; the process adaptation module adjusts the cooling strategy based on the material type, stamping speed and material thickness.

9. A control method for the phase change cooling system according to any one of claims 1 to 8, characterized in that: include: The mold temperature change trend is periodically output through the spatiotemporal prediction model of the prediction correction layer; Dynamically adjust the temperature setting value of the real-time control layer based on the temperature change trend; In the real-time control layer, the valve opening control quantity of the cooling medium circulation loop is calculated and output based on the deviation between the adjusted temperature setting value and the measured temperature.

10. The control method according to claim 9, characterized in that: Also includes: When a sudden change in process parameters is detected, the frequency domain features of the current temperature signal are extracted; According to the extracted frequency domain feature intensity, the differential action or the integral action of the proportional-integral-differential controller in the real-time control layer is enhanced.

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