Water temperature estimation method and device, electronic equipment, storage medium and vehicle

Abstract

The invention discloses a water temperature estimation method and device, electronic equipment, a storage medium and a vehicle. The method comprises the following steps: acquiring heating electric power and circuit board temperature of an electronic device; the electronic device is fixed on the circuit board and is connected with a heat dissipation element which is in contact with the water path; when the current stage of the electronic device is a steady-state stage, calculating a steady-state heat transfer proportion at the current temperature sampling moment according to a first temperature difference between the current temperature sampling moment and the circuit board temperature at the previous temperature sampling moment; according to the steady-state heat transfer proportion, calculating a first heat dissipation amount of the electronic device for dissipating heat to the heat dissipation element under the heating electric power and a second heat dissipation amount of the electronic device for dissipating heat to the circuit board; and estimating the waterway end water temperature of the heat dissipation element according to the first heat dissipation capacity and the second heat dissipation capacity. According to the method, the steady-state heat transfer proportion is calculated, and the fact that the proportions of outward heat transfer of the electronic device under different conditions are different is considered, so that the estimation of the water temperature of the end part of the waterway when the electronic device is in the steady-state stage is more accurate.

Description

Technical Field

[0001] The present invention relates to the technical field related to vehicles, and in particular to a water temperature estimation method, device, electronic equipment, storage medium and vehicle. Background Art

[0002] When cooling electronic devices, such as chips, a temperature sensor is usually set to measure the temperature in order to monitor the temperature of the electronic device. In addition, the electronic device will be connected to a heat dissipation element, and heat conduction is performed through water in the heat dissipation element to achieve heat dissipation.

[0003] In order to monitor the end water temperature in the water circuit of the heat dissipation element, for example, to monitor the water temperature at the water circuit outlet and the water circuit inlet, it is necessary to monitor the water temperature in the water circuit.

[0004] In order to reduce costs, the water temperature at the end of the water path of the heat dissipation element connected to the electronic device can be determined by the thermal resistance model of the electronic device, thereby reducing the use of water temperature sensors.

[0005] However, the heat dissipation of electronic devices will change when they are in different working states. For example, in the steady state stage, the upstream water temperature in the water circuit of the heat dissipation element changes, which will cause the heat transfer from the electronic device to the heat dissipation element and the circuit board to change. The existing technology does not take this situation into consideration, making the existing thermal resistance model inaccurate when estimating the water temperature at the end of the water channel. Summary of the invention

[0006] Based on this, it is necessary to provide a water temperature estimation method, device, electronic device, storage medium and vehicle to address the technical problem of inaccurate water temperature estimation at the end of the water channel during the steady-state stage of electronic devices in the prior art.

[0007] The present invention provides a water temperature estimation method, comprising:

[0008] Acquiring the heating power of the electronic device and the temperature of the circuit board; the electronic device is fixed on the circuit board, and the electronic device is connected to a heat dissipation element in contact with the water channel;

[0009] When the current stage of the electronic device is a steady-state stage, the steady-state heat transfer ratio at the current temperature sampling moment is calculated according to the first temperature difference between the temperature of the circuit board at the current temperature sampling moment and the temperature of the circuit board at the previous temperature sampling moment, and the steady-state heat transfer ratio is the heat transfer distribution ratio of the electronic device to the heat dissipation element and to the circuit board in the steady-state stage;

[0010] Calculate, according to the steady-state heat transfer ratio, a first heat dissipation amount of heat dissipated by the electronic device to the heat dissipation element under the heating electric power, and a second heat dissipation amount of heat dissipated by the electronic device to the circuit board;

[0011] The water temperature at the end of the water path of the heat dissipating element is estimated according to the first heat dissipation and the second heat dissipation.

[0012] Furthermore, the method further comprises:

[0013] When the electronic device is powered on, if the absolute value of the first temperature difference is less than a preset first state judgment value, and the absolute value of the second temperature difference between the circuit board temperature and the ambient temperature is less than a preset second state judgment value, then the current stage of the electronic device is judged to be a steady state stage, otherwise, the current stage of the electronic device is judged to be a cold start stage;

[0014] When the electronic device is powered off, the current stage of the electronic device is cleared.

[0015] Further, according to a first temperature difference between the temperature of the circuit board at the current temperature sampling moment and the temperature at the previous temperature sampling moment, a steady-state heat transfer ratio at the current temperature sampling moment is calculated, specifically including:

[0016] Calculate the steady-state heat transfer ratio at the current temperature sampling moment:

[0017] Among them, R is the steady-state heat transfer ratio, R0 is the steady-state heat transfer reference ratio, dT is the first temperature difference, k1 is the coefficient of the first steady-state heat transfer ratio relationship formula, k2 is the coefficient of the second steady-state heat transfer ratio relationship formula, and e is a natural constant.

[0018] Further, the calculating, based on the steady-state heat transfer ratio and the heating electric power, a first heat dissipation amount of heat dissipated by the electronic device to a heat dissipation element connected to the electronic device, and a second heat dissipation amount of heat dissipated by the electronic device to the circuit board specifically includes:

[0019] The first heat dissipation is calculated as: Q1=(1-R)Q, and the second heat dissipation is calculated as: Q2=RQ, wherein Q1 is the first heat dissipation, Q2 is the second heat dissipation, Q is the heat generation per unit time of the electronic device calculated based on the heat generation electric power, and R is the steady-state heat transfer ratio.

[0020] Furthermore, estimating the water temperature at the end of the water path of the heat dissipation element according to the first heat dissipation and the second heat dissipation specifically includes:

[0021] Calculate the temperature of the electronic device at the location of the electronic device according to the second heat dissipation and the circuit board temperature and based on the second thermal resistance between the temperature measurement point and the electronic device;

[0022] According to the temperature of the electronic device and the first heat dissipation amount, based on the first thermal resistance between the electronic device and the water path, an average heat exchange water temperature in a heat dissipation element connected to the electronic device is calculated, the average heat exchange water temperature being an average value of the heat exchange temperatures between the heat dissipation element and the electronic device;

[0023] The water temperature at the end of the water path of the heat dissipating element is estimated according to the average water exchange water temperature.

[0024] Further:

[0025] The calculating the temperature of the electronic device at the location of the electronic device based on the second heat dissipation and the circuit board temperature and based on the second thermal resistance between the temperature measurement point and the electronic device specifically includes: calculating the second thermal resistance between the temperature measurement point and the electronic device as:

[0026] Where R2 is the second thermal resistance, L2 is the temperature measurement distance from the temperature measurement point to the middle of the electronic device, L1 is the radius of the electronic device, δ is the thickness of the circuit board, λ PCB is the thermal conductivity of the circuit board;

[0027] Calculate the temperature of the electronic device as: T e =T2+Q2·R2, where T e is the temperature of the electronic device, T2 is the temperature of the circuit board, Q2 is the second heat dissipation, and R2 is the second thermal resistance;

[0028] The calculating, based on the temperature of the electronic device and the first heat dissipation amount and the first thermal resistance between the electronic device and the water path, the average water exchange temperature in the heat dissipation element connected to the electronic device specifically includes: calculating the average water exchange temperature as: T w =T e -R1·Q1, where T w is the average water exchange temperature, T e is the temperature of the electronic device, R1 is the first thermal resistance, and Q1 is the first heat dissipation.

[0029] Furthermore, the water temperature at the end of the water channel of the heat dissipating element includes the water temperature at the water channel inlet, and the estimating the water temperature at the end of the water channel of the heat dissipating element according to the average water exchange water temperature specifically includes:

[0030] According to the structural thickness of each layer between the electronic device and the heat dissipation element, the thermal conductivity coefficient of each layer and the area of ​​each layer, the thermal conduction resistance from the electronic device to the heat dissipation element is calculated as: Among them, R 1,cond is the thermal conduction resistance, δ iis the structural thickness of the i-th layer, λ i is the thermal conductivity of the i-th layer, A i is the area of ​​the i-th layer, and n is the number of layers;

[0031] The wall temperature of the heat dissipation element in contact with water is calculated as: T wall =T e -Q1·R 1,cond , where T wall is the wall temperature, T e is the temperature of the electronic device, Q1 is the first heat dissipation, R 1,cond is the thermal conduction thermal resistance;

[0032] The estimated water temperature at the waterway inlet is: Among them, T in is the water temperature at the water channel inlet, α is the water heat transfer coefficient, is the water mass flow rate, Cp w is the specific heat of water at constant pressure, A w is the water heat transfer area, T w is the average water exchange temperature, T wall is the wall temperature.

[0033] Furthermore, the water temperature at the end of the water channel of the heat dissipating element also includes the water temperature at the water channel outlet, and the estimating the water temperature at the end of the water channel of the heat dissipating element according to the average water exchange water temperature specifically includes:

[0034] The estimated water temperature at the waterway outlet is: Among them, T out is the water temperature at the water channel outlet, R is the heat exchange area per unit length, and L is the water channel length.

[0035] The present invention provides a water temperature estimation device, comprising:

[0036] An acquisition module is used to acquire the heating power of the electronic device and the temperature of the circuit board; the electronic device is fixed on the circuit board, and the electronic device is connected to a heat dissipation element in contact with the water channel;

[0037] a steady-state heat transfer ratio calculation module, for calculating the steady-state heat transfer ratio at the current temperature sampling moment when the current stage of the electronic device is the steady-state stage, according to a first temperature difference between the temperature of the circuit board at the current temperature sampling moment and the temperature of the previous temperature sampling moment, wherein the steady-state heat transfer ratio is a heat transfer distribution ratio of the electronic device to the heat dissipation element and to the circuit board in the steady-state stage;

[0038] a heat dissipation calculation module, used for calculating a first heat dissipation of the electronic device to the heat dissipation element under the heating electric power and a second heat dissipation of the electronic device to the circuit board according to the steady-state heat transfer ratio;

[0039] A water temperature calculation module at the end of the water channel is used to estimate the water temperature at the end of the water channel of the heat dissipation element according to the first heat dissipation and the second heat dissipation.

[0040] The present invention provides an electronic device, comprising:

[0041] at least one processor; and,

[0042] a memory communicatively connected to at least one of the processors; wherein,

[0043] The memory stores instructions that can be executed by at least one of the processors. The instructions are executed by at least one of the processors to enable the at least one of the processors to perform the water temperature estimation method as described above.

[0044] The present invention provides a storage medium, wherein the storage medium stores computer instructions. When a computer executes the computer instructions, the storage medium is used to execute all steps of the water temperature estimation method as described above.

[0045] The present invention provides a vehicle, comprising the water temperature estimation device as described above, or the electronic device as described above.

[0046] According to the present invention, when the current stage of the electronic device is a steady-state stage, the steady-state heat transfer ratio at the current temperature sampling moment is calculated according to the first temperature difference between the temperature of the circuit board at the current temperature sampling moment and the temperature of the previous temperature sampling moment. The steady-state heat transfer ratio is the heat transfer distribution ratio of the electronic device to the heat dissipation element and to the circuit board in the steady-state stage; the first heat dissipation amount of the electronic device to the heat dissipation element under the heating electric power and the second heat dissipation amount of the electronic device to the circuit board are calculated according to the steady-state heat transfer ratio, and the water temperature at the end of the water path in the heat dissipation element is estimated according to the first heat dissipation amount and the second heat dissipation amount. Therefore, the present invention takes into account that the proportion of heat transfer to the outside of the electronic device under different circumstances is different. By calculating the steady-state heat transfer ratio and based on the steady-state heat transfer ratio, the first heat dissipation amount of the electronic device to the heat dissipation element under the heating electric power and the second heat dissipation amount of the electronic device to the circuit board in the steady-state stage are obtained, so that the water temperature at the end of the water path of the electronic device in the steady-state stage is estimated more accurately. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 This is a working flow chart of a water temperature estimation method according to an embodiment of the present invention;

[0048] Figure 2 This is a working flow chart of a water temperature estimation method according to another embodiment of the present invention;

[0049] Figure 3 A schematic diagram of a heat conduction model according to an embodiment of the present invention;

[0050] Figure 4 A flowchart for determining the current stage of an electronic device in accordance with the best embodiment of the present invention;

[0051] Figure 5 This is a schematic diagram of building a waterway flow model according to an example of the present invention;

[0052] Figure 6 A schematic diagram of the calculation effect of an example of the present invention;

[0053] Figure 7 A schematic diagram of a water temperature estimation device according to an embodiment of the present invention;

[0054] Figure 8 The figure is a schematic diagram of the hardware structure of an electronic device of the present invention. DETAILED DESCRIPTION

[0055] The specific embodiments of the present invention are further described below in conjunction with the accompanying drawings. The same components are represented by the same reference numerals. It should be noted that the words "front", "rear", "left", "right", "upper" and "lower" used in the following description refer to directions in the accompanying drawings, and the words "inner" and "outer" refer to directions toward or away from the geometric center of a specific component, respectively.

[0056] like Figure 1 The figure shows a working flow chart of a water temperature estimation method according to an embodiment of the present invention, comprising:

[0057] Step S101, obtaining the heating power of the electronic device and the temperature of the circuit board; the electronic device is fixed on the circuit board, and the electronic device is connected to a heat dissipation element in contact with the water channel;

[0058] Step S102, when the current stage of the electronic device is a steady-state stage, the steady-state heat transfer ratio at the current temperature sampling moment is calculated according to the first temperature difference between the temperature of the circuit board at the current temperature sampling moment and the temperature of the circuit board at the previous temperature sampling moment, wherein the steady-state heat transfer ratio is the heat transfer distribution ratio of the electronic device to the heat dissipation element and to the circuit board in the steady-state stage;

[0059] Step S103, calculating a first heat dissipation amount of the electronic device to the heat dissipation element under the heating electric power and a second heat dissipation amount of the electronic device to the circuit board according to the steady-state heat transfer ratio;

[0060] Step S104: estimating the water temperature at the end of the water path of the heat dissipation element according to the first heat dissipation and the second heat dissipation.

[0061] Specifically, the present invention can be applied to electronic devices with processing capabilities, such as an electronic control unit (ECU) or an extended domain control unit (XCU) of a vehicle.

[0062] Specifically, first, the electronic device executes step S101 to obtain the heating power of the electronic device and the temperature of the circuit board.

[0063] In some embodiments, the electronic device is a chip.

[0064] like Figure 3 The figure shows a schematic diagram of a heat conduction model of an embodiment of the present invention, including an electronic device 1, a circuit board 2 and a heat dissipation element 3. The heat source is the heat generation power of the electronic device 1, which is completely converted into heat because it does not need to do work externally. The circuit board 2 (Printed Circuit Board, PCB) connected to the electronic device 1 has poor thermal conductivity, so the heat dissipation Q to the environment is 环 It can be ignored. The heat generated by the electronic device 1 is transferred through the circuit board 2 and the contacting heat dissipation element 3 respectively. The heat dissipation element 3 is preferably a heat dissipation plate, such as a heat dissipation aluminum plate. The heat dissipation element contacts the cooling water in the water channel and transfers the heat to the cooling water. The water channel refers to a passage formed by the heat dissipation element for the circulation of cooling water. The heat dissipated through the heat dissipation element 3 accounts for more than 90% of the total amount. The electronic device 1 is connected to the heat dissipation element 3 through the heat conductive structure 4. The heat dissipated by the electronic device 1 to the water through the heat dissipation element 3 is Q 水 .

[0065] A sensor is provided at the temperature measurement point 21 of the circuit board 2 to obtain the temperature of the circuit board through the sensor, wherein the distance from the temperature measurement point 21 to the center position of the electronic device 1 is the sensor measurement distance L2.

[0066] Then, step S102 is executed to determine whether the current stage of the electronic device is a steady-state stage. When the current stage of the electronic device is a steady-state stage, the steady-state heat transfer ratio at the current temperature sampling moment is calculated based on the first temperature difference between the circuit board temperature at the current temperature sampling moment and the previous temperature sampling moment.

[0067] The state of the electronic device is in the steady state stage during normal use, and after powering off and then powering on again, the electronic device transitions from the cold start stage to the steady state stage. Therefore, by judging whether the electronic device is in the steady state stage, and in the steady state stage, according to the steady state heat transfer ratio relationship, according to the first temperature difference between the temperature of the circuit board at the current temperature sampling moment and the temperature of the previous temperature sampling moment, the steady state heat transfer ratio is determined. The steady state heat transfer ratio is the heat transfer distribution ratio of the electronic device to the heat dissipation element and to the circuit board in the steady state stage.

[0068] Then, step S103 is performed to calculate a first heat dissipation amount of the electronic device to the heat dissipation element under the heating electric power and a second heat dissipation amount of the electronic device to the circuit board according to the steady-state heat transfer ratio.

[0069] Specifically, the heat generation electric power of the electronic device can be used as the heat dissipation per unit time of the electronic device. Based on the heat generation electric power, the heat dissipation per unit time Q of the electronic device can be calculated as the product of the heat generation electric power and the unit time. Then the heat dissipation per unit time of the electronic device can be decomposed into a first heat dissipation Q1 through the heat dissipation element and a second heat dissipation Q2 through the circuit board. The heat dissipation element is preferably an aluminum plate. According to the steady-state heat transfer ratio and the heat generation electric power of the electronic device, the first heat dissipation and the second heat dissipation can be calculated.

[0070] Finally, step S104 is executed to estimate the water temperature at the end of the water path of the heat dissipating element according to the first heat dissipation and the second heat dissipation based on steady-state heat exchange.

[0071] Specifically, the average water temperature for heat exchange is calculated based on the first heat dissipation and the second heat dissipation calculated in step S103, and the water temperature at the end of the water channel of the heat dissipating element is estimated based on the average water temperature for heat exchange. The average water temperature for heat exchange is the average value of the heat exchange temperature between the heat dissipating element and the electronic device. Since the water in the heat dissipating element flows in from the water channel inlet, exchanges heat with the electronic device, and then flows out from the water channel outlet, the water temperature at the end of the water channel in the heat dissipating element is different from the average water temperature for heat exchange. In order to obtain the water temperature at the end of the water channel, the wall temperature of the pipe wall of the heat dissipating element in contact with water can be calculated based on the average water temperature for heat exchange. Steady-state heat exchange means that the temperature distribution in the entire heat exchange system, including the electronic components as heat sources and the heat transfer elements for heat dissipation, does not change, wherein the temperature distribution does not change means that the temperature at each point does not change or changes very slightly. Under the condition of uniform wall temperature, based on the wall temperature, the relationship between the average water temperature for heat exchange and the water temperature at the end of the water channel in the heat dissipating element can be obtained. Thus, the water temperature at the end of the water channel in the heat dissipating element is estimated based on the average water temperature for heat exchange.

[0072] In some embodiments, the water temperature at the end of the water channel is the water temperature at the water channel inlet or the water temperature at the water channel outlet.

[0073] According to the present invention, when the current stage of the electronic device is a steady-state stage, the steady-state heat transfer ratio at the current temperature sampling moment is calculated according to the first temperature difference between the temperature of the circuit board at the current temperature sampling moment and the temperature of the previous temperature sampling moment. The steady-state heat transfer ratio is the heat transfer distribution ratio of the electronic device to the heat dissipation element and to the circuit board in the steady-state stage; the first heat dissipation amount of the electronic device to the heat dissipation element under the heating electric power and the second heat dissipation amount of the electronic device to the circuit board are calculated according to the steady-state heat transfer ratio, and the water temperature at the end of the water path in the heat dissipation element is estimated according to the first heat dissipation amount and the second heat dissipation amount. Therefore, the present invention takes into account that the proportion of heat transfer to the outside of the electronic device under different circumstances is different. By calculating the steady-state heat transfer ratio and based on the steady-state heat transfer ratio, the first heat dissipation amount of the electronic device to the heat dissipation element under the heating electric power and the second heat dissipation amount of the electronic device to the circuit board in the steady-state stage are obtained, so that the water temperature at the end of the water path of the electronic device in the steady-state stage is estimated more accurately.

[0074] like Figure 2 The flowchart of a water temperature estimation method in another embodiment of the present invention is shown, comprising:

[0075] Step S201, obtaining the heating power of the electronic device and the temperature of the circuit board; the electronic device is fixed on the circuit board, and the electronic device is connected to a heat dissipation element in contact with the water channel.

[0076] Step S202, when the electronic device is powered on, if the absolute value of the first temperature difference is less than the preset first state judgment value, and the absolute value of the second temperature difference between the circuit board temperature and the ambient temperature is less than the preset second state judgment value, then the current stage of the electronic device is judged to be the steady-state stage, otherwise the current stage of the electronic device is judged to be the cold start stage; when the electronic device is powered off, the current stage of the electronic device is cleared.

[0077] Step S203, when the current stage of the electronic device is a steady-state stage, the steady-state heat transfer ratio at the current temperature sampling moment is calculated according to the first temperature difference between the temperature of the circuit board at the current temperature sampling moment and the temperature of the circuit board at the previous temperature sampling moment, and the steady-state heat transfer ratio is the heat transfer distribution ratio of the electronic device to the heat dissipation element and to the circuit board in the steady-state stage.

[0078] In one embodiment, the calculating of the steady-state heat transfer ratio at the current temperature sampling moment according to the first temperature difference between the temperature of the circuit board at the current temperature sampling moment and the temperature at the previous temperature sampling moment specifically includes:

[0079] Calculate the steady-state heat transfer ratio at the current temperature sampling moment:

[0080] Among them, R is the steady-state heat transfer ratio, R0 is the steady-state heat transfer reference ratio, dT is the first temperature difference, k1 is the coefficient of the first steady-state heat transfer ratio relationship formula, k2 is the coefficient of the second steady-state heat transfer ratio relationship formula, and e is a natural constant.

[0081] Step S204, calculating a first heat dissipation amount of the electronic device to the heat dissipation element under the heating electric power and a second heat dissipation amount of the electronic device to the circuit board according to the steady-state heat transfer ratio.

[0082] In one embodiment, calculating, according to the steady-state heat transfer ratio, a first heat dissipation amount of heat dissipated by the electronic device to the heat dissipation element under the heating electric power, and a second heat dissipation amount of heat dissipated by the electronic device to the circuit board specifically includes:

[0083] The first heat dissipation is calculated as: Q1=(1-R)Q, and the second heat dissipation is calculated as: Q2=RQ, wherein Q1 is the first heat dissipation, Q2 is the second heat dissipation, Q is the heat generation per unit time of the electronic device calculated based on the heat generation electric power, and R is the steady-state heat transfer ratio.

[0084] Step S205: Calculate the temperature of the electronic device at the location of the electronic device according to the second heat dissipation and the circuit board temperature and based on a second thermal resistance between the temperature measurement point and the electronic device.

[0085] In one embodiment, the calculating the temperature of the electronic device at the location of the electronic device based on the second heat dissipation and the circuit board temperature and based on the second thermal resistance between the temperature measurement point and the electronic device specifically includes: calculating the second thermal resistance between the temperature measurement point and the electronic device as:

[0086] Where R2 is the second thermal resistance, L2 is the temperature measurement distance from the temperature measurement point to the middle of the electronic device, L1 is the radius of the electronic device, δ is the thickness of the circuit board, λ PCB is the thermal conductivity of the circuit board;

[0087] Calculate the temperature of the electronic device as: T e =T2+Q2·R2, where T e is the temperature of the electronic device, T2 is the temperature of the circuit board, Q2 is the second heat dissipation, and R2 is the second thermal resistance.

[0088] Step S206, calculating an average heat exchange water temperature in a heat dissipation element connected to the electronic device according to the temperature of the electronic device, the first heat dissipation, and based on a first thermal resistance between the electronic device and the water path, wherein the average heat exchange water temperature is an average value of the heat exchange temperatures between the heat dissipation element and the electronic device.

[0089] In one embodiment, the calculating, based on the temperature of the electronic device and the first heat dissipation amount and based on the first thermal resistance between the electronic device and the water path, an average water exchange temperature in a heat dissipation element connected to the electronic device specifically includes: calculating the average water exchange temperature as: T w =T e -R1·Q1, where T w is the average water exchange temperature, T e is the temperature of the electronic device, R1 is the first thermal resistance, and Q1 is the first heat dissipation.

[0090] Step S207, estimating the water temperature at the end of the water path of the heat dissipating element according to the average water exchange water temperature.

[0091] In one embodiment, the water temperature at the end of the water path of the heat dissipating element includes the water temperature at the water path inlet, and the estimating the water temperature at the end of the water path of the heat dissipating element according to the average water exchange water temperature specifically includes:

[0092] According to the structural thickness of each layer between the electronic device and the heat dissipation element, the thermal conductivity coefficient of each layer and the area of ​​each layer, the thermal conduction resistance from the electronic device to the heat dissipation element is calculated as: Among them, R 1,cond is the thermal conduction resistance, δ i is the structural thickness of the i-th layer, λ i is the thermal conductivity of the i-th layer, A i is the area of ​​the i-th layer, and n is the number of layers;

[0093] The wall temperature of the heat dissipation element in contact with water is calculated as: T wall =T e -Q1·R 1,cond , where T wall is the wall temperature, T e is the temperature of the electronic device, Q1 is the first heat dissipation, R 1,cond is the thermal conduction thermal resistance;

[0094] The estimated water temperature at the waterway inlet is: Among them, T in is the water temperature at the water channel inlet, α is the water heat transfer coefficient, is the water mass flow rate, Cp w is the specific heat of water at constant pressure, A w is the water heat transfer area, Tw is the average water exchange temperature, T wall is the wall temperature.

[0095] In one embodiment, the water temperature at the end of the water path of the heat dissipating element also includes the water temperature at the water path outlet, and the estimating the water temperature at the end of the water path of the heat dissipating element according to the average water exchange water temperature specifically includes:

[0096] The estimated water temperature at the waterway outlet is: Among them, T out is the water temperature at the water channel outlet, R is the heat exchange area per unit length, and L is the water channel length.

[0097] Specifically, step S201 is first performed to obtain the heating power of the electronic device and the temperature of the circuit board.

[0098] Then, step S202 is executed to determine whether the current stage of the electronic device is a steady-state stage. When the electronic device is powered on, if the absolute value of the first temperature difference dT of the circuit board temperature at the current temperature sampling moment and the previous temperature sampling moment is less than the preset first state judgment value, and the absolute value of the second temperature difference between the circuit board temperature and the ambient temperature is less than the preset second state judgment value, then the current stage of the electronic device is determined to be a steady-state stage, otherwise, the current stage of the electronic device is determined to be a cold start stage; and when the electronic device is powered off, the current stage of the electronic device is cleared.

[0099] After the electronic device is powered on, it first goes through a cold start phase, and the temperature rises rapidly. After that, the temperature reaches a stable state, dT = 0, and enters the steady state phase and remains there. In the steady state phase, the temperature may fluctuate slightly. dT = 0 is a steady state condition, and 0 < |dT| <T 阈值 When is the quasi-steady state condition, T 阈值 is a very small temperature threshold. Both the steady-state condition and the quasi-steady-state condition are steady-state stages. Therefore, the stage of the electronic device can be determined based on the temperature.

[0100] In some embodiments, the first state judgment value is the second quantile of the absolute value of the temperature difference between the circuit board temperature at two consecutive temperature sampling moments under steady-state conditions in the big data, such as the 95% quantile. The second state judgment value is the first quantile of the absolute value of the temperature difference between the circuit board temperature and the ambient temperature under steady-state conditions in the big data, such as the 20% quantile.

[0101] Specifically, Figure 4 The flowchart of the best embodiment of the present invention for determining the current stage of an electronic device is shown, the electronic device is a chip, and the method includes:

[0102] Step S401, if the chip is powered off, then execute step S402, otherwise the current stage of the chip remains in the steady state stage;

[0103] Step S402, the chip goes into sleep mode;

[0104] Step S403, the chip is powered on;

[0105] Step S404, if |T2 - T 环 | < Limit2 and dT < Limit1, it is determined as the steady state stage, otherwise it is determined as the cold start stage, i.e., the dynamic stage.

[0106] Among them, Limit1 is the preset first state judgment value, and Limit2 is the preset second state judgment value. Among them, Limit1 is set as the 95% quantile of the absolute value of the temperature difference between the circuit board temperatures at two consecutive temperature sampling moments under steady state conditions in the big data, and Limit2 is set as the 20% quantile of the absolute value of the temperature difference between the measured value of the circuit board temperature and the ambient temperature under steady state conditions in the big data.

[0107] Among them, T2 is the circuit board temperature, and T 环 is the ambient temperature. When the absolute value of the difference between the two is less than the second state judgment value and the absolute value of the first temperature difference dT is less than the first state judgment value, the current stage of the chip is determined as the steady state stage. After entering the steady state stage, when the chip is powered off, the state is cleared and the state is rejudged after power on. When the absolute value of the temperature difference between the circuit board temperature and the ambient temperature is greater than or equal to the second state judgment value or the absolute value of the first temperature difference dT is greater than or equal to the first state judgment value, the current stage of the chip is determined as the cold start state. During the entire cold start process, Tx and the circuit board temperature are compared at each temperature sampling moment to determine whether the current stage still remains as the cold start stage.

[0108] Then, when the current stage of the electronic device is the steady state stage, step S203 is executed to calculate the steady state heat transfer ratio at the current temperature sampling moment according to the first temperature difference between the circuit board temperatures at the current temperature sampling moment and the previous temperature sampling moment. The steady state heat transfer ratio is the heat transfer distribution ratio of the electronic device to the heat dissipation element and to the circuit board under the steady state stage.

[0109] In one embodiment, calculating the steady state heat transfer ratio at the current temperature sampling moment according to the first temperature difference between the circuit board temperatures at the current temperature sampling moment and the previous temperature sampling moment specifically includes:

[0110] Calculating the steady state heat transfer ratio at the current temperature sampling moment as:

[0111] Among them, R is the steady-state heat transfer ratio, R0 is the steady-state heat transfer reference ratio, dT is the first temperature difference between the circuit board temperature at the current temperature sampling moment and the previous temperature sampling moment, k1 is the first steady-state heat transfer proportional relationship coefficient, k2 is the second steady-state heat transfer proportional relationship coefficient, and e is a natural constant.

[0112] Specifically, the steady-state heat transfer proportional relationship is established as:

[0113]

[0114] Among them, R is the steady-state heat transfer ratio, R0 is the steady-state heat transfer reference ratio, dT is the first temperature difference between the circuit board temperature at the current temperature sampling moment and the previous temperature sampling moment, k1 is the first steady-state heat transfer proportional relationship coefficient, k2 is the second steady-state heat transfer proportional relationship coefficient, and e is a natural constant.

[0115] In some embodiments, the electronic device is a chip, the heat dissipation element is a heat dissipation aluminum plate, and the steady-state heat transfer reference ratio is the chip-aluminum plate steady-state heat transfer reference ratio, which is set to R0=0.9.

[0116] This embodiment provides a steady-state heat transfer proportional relationship. The coefficient k1 of the first steady-state heat transfer proportional relationship in formula (1) represents the proportional relationship between dR and dT, that is, a larger dT will cause a larger dR. The coefficient k2 of the second steady-state heat transfer proportional relationship represents the scaling factor of dT, which can fit the speed of change of R with dT in dynamic changes, that is, the size of the temperature transfer capacity. The right side of formula (1) uses a sigmoid function. On the one hand, the exponential function is more in line with the law of heat conduction change. On the other hand, R tends to saturation with the increase of dT, avoiding factors such as error interference that cause excessive R changes caused by excessive dT.

[0117] In some embodiments, the thermal resistance steady-state model includes at least: a heat dissipation distribution equation, a device temperature equation, and a water temperature equation.

[0118] Therefore, the thermal resistance steady-state model includes:

[0119] Step S204, calculating a first heat dissipation amount of the electronic device to the heat dissipation element under the heating power and a second heat dissipation amount of the electronic device to the circuit board according to the steady-state heat transfer ratio; and

[0120] Step S205, calculating the electronic device temperature at the location of the electronic device according to the second heat dissipation and the circuit board temperature and based on a second thermal resistance between the temperature measurement point and the electronic device; and

[0121] Step S206 , calculating an average water exchange temperature in a heat dissipation element connected to the electronic device according to the temperature of the electronic device, the first heat dissipation, and based on a first thermal resistance between the electronic device and the water path.

[0122] In one embodiment, calculating, according to the steady-state heat transfer ratio, a first heat dissipation amount of heat dissipated by the electronic device to the heat dissipation element under the heating electric power, and a second heat dissipation amount of heat dissipated by the electronic device to the circuit board specifically includes:

[0123] The first heat dissipation is calculated as: Q1=(1-R)Q, and the second heat dissipation is calculated as: Q2=RQ, wherein Q1 is the first heat dissipation, Q2 is the second heat dissipation, Q is the heat generation per unit time of the electronic device calculated based on the heat generation electric power, and R is the steady-state heat transfer ratio.

[0124] Specifically, after the steady-state heat transfer proportional relationship is determined, the first heat dissipation and the second heat dissipation are calculated using the heat dissipation distribution relationship.

[0125] Based on the heating power, the heat dissipation per unit time Q of the electronic device can be calculated as the product of the heating power and the unit time. Then the heat dissipation per unit time of the electronic device can be decomposed into the first heat dissipation Q1 through the heat dissipation element and the second heat dissipation Q2 through the circuit board. The heat dissipation element is preferably an aluminum plate.

[0126] The first heat dissipation Q1 and the second heat dissipation Q2 are respectively:

[0127] Q1=(1-R)Q (2)

[0128] Q2=RQ (3)

[0129] Among them, Q1 is the first heat dissipation, Q2 is the second heat dissipation, Q is the heat generation per unit time of the electronic device calculated according to the heat generation electric power, and R is the steady-state heat transfer ratio.

[0130] More specifically, the first temperature difference is the temperature difference between the circuit board temperature at the current temperature sampling moment and the previous temperature sampling moment, and the absolute value of the first temperature difference is the absolute value of the temperature difference between the circuit board temperature at the current temperature sampling moment and the previous temperature sampling moment.

[0131] In this embodiment, a first heat dissipation amount through the heat dissipation element and a second heat dissipation amount through the circuit board are determined in combination with a steady-state heat transfer ratio.

[0132] In one embodiment, the calculating the temperature of the electronic device at the location of the electronic device based on the second heat dissipation and the circuit board temperature and based on the second thermal resistance between the temperature measurement point and the electronic device specifically includes: calculating the second thermal resistance between the temperature measurement point and the electronic device as:

[0133] Where R2 is the second thermal resistance, L2 is the temperature measurement distance from the temperature measurement point to the middle of the electronic device, L1 is the radius of the electronic device, δ is the thickness of the circuit board, λ PCB is the thermal conductivity of the circuit board;

[0134] Calculate the temperature of the electronic device as: T e =T2+Q2·R2, where T e is the temperature of the electronic device, T2 is the temperature of the circuit board, Q2 is the second heat dissipation, and R2 is the second thermal resistance.

[0135] Specifically, assuming that the temperature distribution from the center of the electronic device to the circuit board conforms to the circular distribution in a steady state, the heat dissipation per unit time in the radial direction is:

[0136]

[0137] Where Q is the radial heat dissipation per unit time of the electronic device, that is, the heat generation power of the electronic device. R is the radial distance of the chip, δ is the thickness of the circuit board, λ is the thermal conductivity, A is the heat exchange area, λ PCB is the thermal conductivity of the circuit board. The second thermal resistance from the temperature measurement point to the electronic device can be obtained by integrating formula (4) from L1 to L2, that is:

[0138]

[0139] Wherein, R2 is the second thermal resistance, L2 is the sensor measurement distance from the temperature measurement point to the center of the electronic device, L1 is the radius of the electronic device, δ is the thickness of the circuit board, λ PCB is the thermal conductivity of the circuit board.

[0140] Then, in the steady-state stage, the temperature of the electronic device can be calculated by the device temperature relationship, that is, formula (6):

[0141] T e =T2+Q2·R2 (6)

[0142] Among them, T e is the temperature of the electronic device, T2 is the temperature of the circuit board, Q2 is the second heat dissipation, and R2 is the second thermal resistance.

[0143] This embodiment determines the accurate temperature of the electronic device through the second thermal resistance.

[0144] In one embodiment, the calculating, based on the temperature of the electronic device and the first heat dissipation amount and based on the first thermal resistance between the electronic device and the water path, an average water exchange temperature in a heat dissipation element connected to the electronic device specifically includes: calculating the average water exchange temperature as: T w =T e -R1·Q1, where T w is the average water exchange temperature, T e is the temperature of the electronic device, R1 is the first thermal resistance, and Q1 is the first heat dissipation.

[0145] Specifically, the average water exchange temperature is calculated as:

[0146] T w =T e -R1·Q1 (7)

[0147] Where T w is the average water exchange temperature, T e is the temperature of the electronic device, R1 is the first thermal resistance, and Q1 is the first heat dissipation.

[0148] Specifically, the first thermal resistance is calculated. Figure 3 As shown, the first thermal resistance is the thermal conduction resistance R from the electronic device 1 to the heat dissipation element 3 1,cond The convection heat transfer resistance R between the heat dissipation element 3 and water 1,conv sum.

[0149] In some embodiments, the method further comprises:

[0150] Calculate the heat conduction thermal resistance from the electronic device to the heat dissipation element according to the structural thickness of each layer between the electronic device and the heat dissipation element, the thermal conductivity coefficient of each layer and the area of ​​each layer, wherein the electronic device is connected to the heat dissipation element through one or more heat-conducting structures, and the layers include multiple structural layers in the electronic device, one or more heat-conducting structures and the heat dissipation element;

[0151] Calculating the convection heat transfer thermal resistance between the heat dissipation element and water;

[0152] The first thermal resistance between the electronic device and the water in the heat dissipation element is calculated as the sum of the thermal conduction resistance and the convection resistance, that is, R1 = R 1,cond +R 1,conv , where R1 is the first thermal resistance, R 1,cond is the thermal conduction resistance, R 1,conv is the convective heat transfer thermal resistance.

[0153] Specifically, electronic devices generally include multiple structural layers. Taking a chip as an example, the structural layers of a chip generally include: substrate layer, solder layer, substrate layer, heat source layer, active layer, etc. Each structural layer has a structural thickness and area of ​​each layer, and each structural layer has a thermal conductivity coefficient of each layer according to the material of the different layers.

[0154] Therefore, the thermal resistance of heat conduction from the electronic device to the heat dissipation element is calculated according to the structural thickness of each layer between the electronic device and the heat dissipation element, the thermal conductivity coefficient of each layer and the area of ​​each layer. In addition, the layer between the electronic device and the heat dissipation element also includes a heat-conducting structure and a heat dissipation element. The heat-conducting structure includes various existing thermally conductive adhesives and thermally conductive parts. Each thermally conductive adhesive or thermally conductive part is regarded as a layer. At the same time, since the heat dissipation element is generally a flat plate, the heat dissipation element is regarded as a whole layer. By calculating the relevant parameters of each layer between the electronic device and the heat dissipation element, the thermal resistance of heat conduction from the electronic device to the heat dissipation element is obtained.

[0155] In some embodiments, the heat conduction thermal resistance from the electronic device to the heat dissipation element is calculated based on the structural thickness of each layer between the electronic device and the heat dissipation element, the thermal conductivity coefficient of each layer, and the area of ​​each layer, specifically including:

[0156] Calculate the thermal resistance of heat conduction as: Among them, R 1,cond is the thermal conduction resistance, δ i is the structural thickness of the i-th layer, λ i is the thermal conductivity of the i-th layer, A i is the area of ​​the i-th layer, and n is the number of layers.

[0157] Specifically, the thermal conduction resistance is calculated using formula (8):

[0158]

[0159] Among them, R 1,cond is the thermal conduction resistance, δ i is the structural thickness of the i-th layer, λ i is the thermal conductivity of the i-th layer, A i is the area of ​​the i-th layer, and n is the number of layers.

[0160] This embodiment provides a method for calculating the thermal conductivity.

[0161] Then the convective heat transfer thermal resistance between the heat dissipation element and the water is calculated. The convective heat transfer thermal resistance can be calculated based on the water heat exchange area.

[0162] In some embodiments, the convective heat transfer resistance between the heat dissipation element and water is calculated as: Among them, R 1,conv is the convection heat transfer thermal resistance, A w is the water heat transfer area, and α is the water heat transfer coefficient.

[0163] Finally, the water temperature in the heat dissipation element can be calculated according to the temperature of the electronic device, the first thermal resistance, and the first heat dissipation. The water temperature in the heat dissipation element calculated according to the temperature of the electronic device, the first thermal resistance, and the first heat dissipation is the average water exchange temperature.

[0164] This embodiment calculates the average water exchange temperature in the heat dissipation element based on the thermal resistance.

[0165] In some embodiments, the method further comprises:

[0166] Obtaining, under the test condition, the test value of the first temperature difference, the test value of the heating electric power, the test value of the circuit board temperature, and the test value of the water temperature;

[0167] Substituting the steady-state heat transfer proportional relationship into the thermal resistance steady-state model;

[0168] Taking the test value of the first temperature difference, the test value of the heating electric power, and the test value of the circuit board temperature as input variables, the thermal resistance steady-state model is trained based on the deviation between the average water exchange water temperature output by the thermal resistance steady-state model and the test value of the water temperature to obtain the first steady-state heat transfer proportional relationship coefficient and the second steady-state heat transfer proportional relationship coefficient.

[0169] Specifically, in the test condition, the test temperature difference is obtained as dT. The test temperature difference is the first temperature difference between the temperature of the circuit board at the current temperature sampling moment and the temperature of the previous temperature sampling moment, and then is brought into formula (1) and embedded into the thermal resistance steady-state model of the electronic device, that is, substituted into formula (2).

[0170] The test conditions should include all input and output variable ranges of the model, including control variables such as valve opening, pump speed, and state variables such as temperature. The test conditions can include all steady-state and quasi-steady-state conditions.

[0171] Based on the test values ​​obtained under the test conditions, the deviation between the average water exchange water temperature output by the training model and the measured value of the water temperature obtained under the test conditions is globally optimized using least squares to obtain the final k1 and k2.

[0172] Substitute k1 and k2 into formula (1) to form the final dynamic thermal resistance model.

[0173] Finally, step S207 is executed to estimate the water temperature at the end of the water path of the heat dissipating element according to the average water exchange water temperature based on steady-state heat exchange.

[0174] Specifically, the thermal resistance steady-state model outputs the average water temperature of the exchange water. Since the water channel sensor is usually arranged upstream or downstream, it is necessary to calculate the inlet and outlet water temperatures through the average water temperature. The first step in calculating the water temperature is to calculate the wall temperature in contact with the water.

[0175] In some embodiments, the wall temperature of the heat dissipation element tube wall is calculated according to the first heat dissipation amount and the heat conduction thermal resistance.

[0176] In some embodiments, calculating the wall temperature of the heat dissipation element tube wall according to the first heat dissipation amount and the heat conduction thermal resistance specifically includes:

[0177] The wall temperature of the heat dissipation element in contact with water is calculated as: T wall =T e -Q1·R 1,cond , where T wall is the wall temperature, T e is the temperature of the electronic device, Q1 is the first heat dissipation, R 1,cond is the thermal conduction resistance.

[0178] The first step in calculating the water temperature is to calculate the temperature of the wall in contact with the water:

[0179] T wall =T e -Q1·R 1,cond (9)

[0180] Where T wall is the wall temperature, T e is the temperature of the electronic device, Q1 is the first heat dissipation, R 1,cond is the thermal conduction resistance.

[0181] Then, the water temperature at the end of the water channel of the heat dissipation element is estimated according to the average water exchange water temperature and the wall temperature.

[0182] In one embodiment, the water temperature at the end of the water channel of the heat dissipation element is the water temperature at the water channel inlet, and the estimating the water temperature at the end of the water channel of the heat dissipation element according to the average water exchange water temperature specifically includes:

[0183] The estimated water temperature at the waterway inlet is: Among them, T in is the water temperature at the water channel inlet, α is the water heat transfer coefficient, is the water mass flow rate, Cp w is the specific heat of water at constant pressure, A w is the water heat transfer area, T wis the average water exchange temperature, T wall is the wall temperature.

[0184] Specifically, under the condition of uniform wall temperature, the steady-state heat transfer in the control volume can be expressed as follows:

[0185]

[0186] Where α is the water heat transfer coefficient, is the water mass flow rate, R is the heat transfer area per unit length, Cp w is the specific heat of water at constant pressure, T0 is the water temperature at position 0, usually the inlet is taken as position 0, T L is the water temperature at position L, dT water is the water temperature difference of the length differential, dx is the length differential, and L is the length of the waterway. The position from the inlet to the length x is referred to as position x, and the integral from the inlet to position x gives:

[0187]

[0188] Among them, T x is the temperature at position x, T in is the water temperature at the waterway inlet, that is, the water temperature T0 at position 0.

[0189] Then the temperature at position x is:

[0190]

[0191] The average water exchange temperature can be calculated as:

[0192]

[0193] From formula (13), the water temperature at the waterway inlet can be obtained:

[0194]

[0195] Among them, T in is the water temperature at the water channel inlet, α is the water heat transfer coefficient, is the water mass flow rate, Cp w is the specific heat of water at constant pressure, A w is the water heat transfer area, T w is the average water exchange temperature, T wall is the wall temperature.

[0196] In one embodiment, the water temperature at the end of the water path of the heat dissipating element also includes the water temperature at the water path outlet, and the estimating the water temperature at the end of the water path of the heat dissipating element according to the average water exchange water temperature specifically includes:

[0197] The estimated water temperature at the waterway outlet is: Among them, Tout is the water temperature at the water channel outlet, R is the heat exchange area per unit length, and L is the water channel length.

[0198] After obtaining the water temperature at the water channel inlet, the water channel outlet water temperature can be calculated according to formula (12). The water channel outlet water temperature T out In fact, it is the temperature T from the inlet to the position with a length of L L , therefore, the water temperature at the waterway outlet is:

[0199]

[0200] Among them, T out It is the water temperature at the waterway outlet.

[0201] The waterway flow model can be constructed using existing physical models.

[0202] In some embodiments, a waterway flow model is constructed through a neural network model to obtain water mass flow.

[0203] The neural network model is established by obtaining physical model data according to experimental data, and then expanded from the physical model data.

[0204] Specifically, the water mass flow rate of the heating element in different states is constant. The heating element is an electronic device that serves as a heat source. Therefore, the existing water flow model building method can be used to build a water flow model, and when the state of the heating element is determined, the corresponding water mass flow rate is obtained. Figure 5 As shown, firstly, the experimental data 501 is acquired, then modeling correction is performed, and the GT Power (engine working process simulation calculation software) model 502 is input, and the mapping database 503 is obtained through DoE, and the ANN flow static model 504 is obtained through feature screening, training, and verification, and the flow dynamic model 505 is obtained through the time constant.

[0205] As an example, the waterway flow model is built as follows:

[0206] 1. Obtain key flow data in the experiment, correct parameters such as pump pressure rise, component pressure drop, and along-the-way loss, build a physical model, and make corrections based on key experimental data.

[0207] 2. Build a physical model based on the experimental data and expand the experimental data. This step can calculate the branch flow that is not measured in the experiment but is relevant to the simulation. Specifically, the physical model is built through GT Power software. Then the database is mapped through the Design of Experiment (DOE). The mapping database can be regarded as a large amount of mapping data corresponding to input and output, and a neural network model can be established.

[0208] 3. Based on the data obtained in step 2, the control quantity in the system is used as the modeling feature, and the feature is expanded according to the physical meaning, as shown in Table 1. The expansion basis can be the order relationship between the pump speed and head, temperature and radiation heat transfer, and the instantaneous energy and cumulative energy entering the system.

[0209] Control volume Extended Features Pump speed Speed ​​2, Speed ​​3, temperature Water temperature 2, water temperature 3, water temperature 4 Valve opening Opening, opening 3 Engine speed, torque Engine speed*torque, ∫ speed*torque

[0210] Feature screening is performed based on the extended features, and the screening method is based on the pan-neural network GRNN with joint probability distribution.

[0211] The screening process is as follows:

[0212] 4.1 Put all the features to be selected into the set to be selected, and the selected set is an empty set at this time;

[0213] 4.2 Use the features in the candidate set to approximate the output value through GRNN, traverse the features in the candidate set, and select the feature with the minimum mean squared error (MSE) to enter the selected set;

[0214] 4.3 Then enter the iterative process, at this time the fitting target is changed to the remaining information after the output value of the feature fitting in the selected set, and the feature with the smallest MSE is selected to enter the selected set;

[0215] 4.4 Iterate in sequence until all the features in the set to be selected are traversed.

[0216] GRNN is based on probability and can better reflect the one-to-one correspondence between the control quantity as the model input and the state quantity as the model output.

[0217] 5. According to the feature order given by the screening results, the first four features that reduce the GRNN fitting MSE to 0 are selected, which can ensure accuracy and avoid feature redundancy.

[0218] 6. Randomly divide the data obtained in step 2 into training sets and test sets, establish a neural network model based on the screening features, use the K test to obtain the accuracy comparison of the model, and select the best traffic model based on the comprehensive training accuracy and test accuracy, that is, Figure 5 Static model of traffic.

[0219] 7. Build a steady-state heat exchange model of the heat exchange components in the system, for example, using the steady-state heat exchange model of this application, or various steady-state heat exchange models in the prior art, and the heat absorbed under steady-state conditions causes its temperature to change

[0220]

[0221] The heat source is the heat exchange between the heating element and the water flow, so there are:

[0222] Q 吸 =α·dA·(T B -T w )=α·L c ·dx·(T B -T w )(17)

[0223] Among them, Q 吸 is the absorbed heat, C p is the specific heat of cooling water at constant pressure, is the cooling water flow rate, T w is the water temperature, T B is the temperature of the heating element, L C is the characteristic length of the heat exchange component, indicating the heat exchange area per unit length, α is the heat transfer coefficient, dA is the differential of the heat exchange area, and dx is the differential of the heat exchange length. Formula (16) and formula (17) are combined and integrated over the length from the inlet to the outlet of the heat exchange component to obtain

[0224]

[0225] Among them, T w,out is the outlet water temperature, T w,in is the inlet water temperature, and A is the heat exchange area.

[0226] Since the thermal mass of the heat exchange component is relatively large relative to the heat transfer amount within a unit step, it can be considered that the temperature of the heat exchange component remains unchanged within a unit step.

[0227] 8. Fit the heat transfer coefficient according to the mass flow rate to ensure that the heat transfer coefficient in the water channel is within a reasonable range and the trend is correct.

[0228] 9. Calculate the heat transfer heat Q within the unit time step, calculate the temperature change of the heat exchange component within the step by formula (16), and update the temperature of the heat exchange component when calculating the next step.

[0229] 10. Identify the characteristic length of the heat exchange element through experimental data, compensate for the lack of flow accuracy, calibrate the flow model, and obtain the following Figure 5 The flow dynamic model shown is a model obtained by adding filtering to the static model of the neural network. According to the flow dynamic model, the water mass flow of cooling water of the heating element, that is, the electronic device, under different conditions can be determined.

[0230] After determining the water mass flow rate, the water heat transfer coefficient can be fitted according to the water mass flow rate or the Reynolds number can be calculated according to the dimensionless method, and then the water heat transfer coefficient can be determined according to the relationship between the Prandtl number and the Nusselt number.

[0231] According to the water mass flow rate, the water heat transfer coefficient can be fitted by a quadratic polynomial, and the formula is as follows:

[0232]

[0233] Where α is the water heat transfer coefficient, is the water mass flow rate, C1, C2, C3 are fitting coefficients, which need to be fitted according to experimental values.

[0234] The dimensionless method involves two flow regimes, laminar and turbulent, which are distinguished by the Reynolds number, which is calculated as:

[0235]

[0236] Nusselt number calculation formula:

[0237]

[0238] In the formula, V is the water flow rate, L is the heat transfer length, v is the dynamic viscosity of water, and λ is the thermal conductivity of water. The water heat transfer coefficient can then be calculated as:

[0239]

[0240] In the formula, Pr is the Prandtl number of water, and f(Re,Pr) is the empirical function used to calculate the Nusselt number. Due to the different internal structures of the water channel, the calculation of Nu in laminar flow, transition state and turbulent flow must be identified based on experimental temperature data.

[0241] In some embodiments, the method further comprises:

[0242] Acquire a plurality of experimental data, wherein the experimental data include measured values ​​of water channel inlet temperatures;

[0243] Estimate the initial value of the Nusselt number according to the empirical function, obtain the initial value of the water heat transfer coefficient according to the initial value of the Nusselt number, and estimate the water temperature at the water channel inlet of the heat dissipation element according to the average water exchange water temperature and the wall temperature. Specifically, calculate the water temperature at the water channel inlet according to formula (14);

[0244] Adjust the Nusselt number and thus the water heat transfer coefficient until the estimated water temperature at the water channel inlet is consistent with the experimental water temperature at the water channel inlet.

[0245] like Figure 6 The figure shows a schematic diagram of the calculation effect of an example of the present invention, including a main circuit test water temperature curve 61, an uncorrected predicted water temperature curve 62, and a water temperature curve 63 predicted by the method of this embodiment. The horizontal axis is time, unit: s, and the vertical axis is temperature, unit: ° C. From the effect, it can be seen that the model after dynamic correction in this embodiment can better predict the water temperature change of electronic devices, such as chips in the dynamic process.

[0246] This embodiment dynamically corrects the water temperature prediction of the heat dissipation element of the electronic device in the steady state stage to solve the delay problem of the existing prediction method. This embodiment simplifies the heat transfer model of the electronic device, reversely infers the water temperature through the temperature change of the device, improves the accuracy through correction, reduces the sensor requirements, and thus reduces costs.

[0247] Based on the same inventive concept, Figure 7 FIG. 1 is a schematic diagram of a water temperature estimation device according to an embodiment of the present invention, comprising:

[0248] The acquisition module 701 is used to acquire the heating power of the electronic device and the temperature of the circuit board; the electronic device is fixed on the circuit board, and the electronic device is connected to a heat dissipation element in contact with the water channel;

[0249] A steady-state heat transfer ratio calculation module 702 is used to calculate the steady-state heat transfer ratio at the current temperature sampling moment according to the first temperature difference between the temperature of the circuit board at the current temperature sampling moment and the temperature of the circuit board at the previous temperature sampling moment when the current stage of the electronic device is the steady-state stage, wherein the steady-state heat transfer ratio is the heat transfer distribution ratio of the electronic device to the heat dissipation element and to the circuit board in the steady-state stage;

[0250] a heat dissipation calculation module 703, for calculating a first heat dissipation of the electronic device to the heat dissipation element under the heating electric power and a second heat dissipation of the electronic device to the circuit board according to the steady-state heat transfer ratio;

[0251] The water temperature calculation module 704 at the end of the water channel is used to estimate the water temperature at the end of the water channel of the heat dissipation element according to the first heat dissipation and the second heat dissipation.

[0252] According to the present invention, when the current stage of the electronic device is a steady-state stage, the steady-state heat transfer ratio at the current temperature sampling moment is calculated according to the first temperature difference between the temperature of the circuit board at the current temperature sampling moment and the temperature of the previous temperature sampling moment. The steady-state heat transfer ratio is the heat transfer distribution ratio of the electronic device to the heat dissipation element and to the circuit board in the steady-state stage; the first heat dissipation amount of the electronic device to the heat dissipation element under the heating electric power and the second heat dissipation amount of the electronic device to the circuit board are calculated according to the steady-state heat transfer ratio, and the water temperature at the end of the water path in the heat dissipation element is estimated according to the first heat dissipation amount and the second heat dissipation amount. Therefore, the present invention calculates the steady-state heat transfer ratio, and based on the steady-state heat transfer ratio, obtains the accurate first heat dissipation amount of the electronic device to the heat dissipation element under the heating electric power in the steady-state stage, and the accurate second heat dissipation amount of the electronic device to the circuit board, thereby replacing the water temperature sensor with an algorithm to reduce costs and estimate the accurate water temperature at the end of the water path of the heat dissipation element when the electronic device is in the steady-state stage.

[0253] In one embodiment, the device further includes a determination module, configured to:

[0254] When the electronic device is powered on, if the absolute value of the second temperature difference between the circuit board temperature and the ambient temperature is less than the preset second state judgment value, and the absolute value of the first temperature difference is less than the preset first state judgment value, then the current stage of the electronic device is judged to be the steady state stage, otherwise, the current stage of the electronic device is judged to be the cold start stage;

[0255] When the electronic device is powered off, the current stage of the electronic device is cleared.

[0256] In one embodiment, the calculating of the steady-state heat transfer ratio at the current temperature sampling moment according to the first temperature difference between the temperature of the circuit board at the current temperature sampling moment and the temperature at the previous temperature sampling moment specifically includes:

[0257] Calculate the steady-state heat transfer ratio at the current temperature sampling moment:

[0258] Among them, R is the steady-state heat transfer ratio, R0 is the steady-state heat transfer reference ratio, dT is the first temperature difference, k1 is the coefficient of the first steady-state heat transfer ratio relationship formula, k2 is the coefficient of the second steady-state heat transfer ratio relationship formula, and e is a natural constant.

[0259] In one embodiment, calculating, based on the steady-state heat transfer ratio and the heat generation electric power, a first heat dissipation amount of heat dissipated by the electronic device to a heat dissipation element connected to the electronic device, and a second heat dissipation amount of heat dissipated by the electronic device to the circuit board specifically includes:

[0260] The first heat dissipation is calculated as: Q1=(1-R)Q, and the second heat dissipation is calculated as: Q2=RQ, wherein Q1 is the first heat dissipation, Q2 is the second heat dissipation, Q is the heat generation per unit time of the electronic device calculated based on the heat generation electric power, and R is the steady-state heat transfer ratio.

[0261] In one embodiment, estimating the water temperature at the end of the water path of the heat dissipation element according to the first heat dissipation and the second heat dissipation specifically includes:

[0262] Calculate the temperature of the electronic device at the location of the electronic device according to the second heat dissipation and the circuit board temperature and based on the second thermal resistance between the temperature measurement point and the electronic device;

[0263] According to the temperature of the electronic device and the first heat dissipation amount, based on the first thermal resistance between the electronic device and the water path, an average heat exchange water temperature in a heat dissipation element connected to the electronic device is calculated, the average heat exchange water temperature being an average value of the heat exchange temperatures between the heat dissipation element and the electronic device;

[0264] The water temperature at the end of the water path of the heat dissipating element is estimated according to the average water exchange water temperature.

[0265] In one embodiment:

[0266] The calculating the temperature of the electronic device at the location of the electronic device according to the second heat dissipation and the circuit board temperature and based on the second thermal resistance between the temperature measurement point and the electronic device specifically includes:

[0267] The second thermal resistance between the temperature measurement point and the electronic device is calculated as:

[0268] Where R2 is the second thermal resistance, L2 is the temperature measurement distance from the temperature measurement point to the middle of the electronic device, L1 is the radius of the electronic device, δ is the thickness of the circuit board, λ PCB is the thermal conductivity of the circuit board;

[0269] Calculate the temperature of the electronic device as: T e =T2+Q2·R2, where T e is the temperature of the electronic device, T2 is the temperature of the circuit board, Q2 is the second heat dissipation, and R2 is the second thermal resistance;

[0270] The calculating, based on the temperature of the electronic device and the first heat dissipation amount and the first thermal resistance between the electronic device and the water path, the average water exchange temperature in the heat dissipation element connected to the electronic device specifically includes: calculating the average water exchange temperature as: T w =T e -R1·Q1, where T w is the average water exchange temperature, T e is the temperature of the electronic device, R1 is the first thermal resistance, and Q1 is the first heat dissipation.

[0271] In one embodiment, the water temperature at the end of the water path of the heat dissipating element includes the water temperature at the water path inlet, and the estimating the water temperature at the end of the water path of the heat dissipating element according to the average water exchange water temperature specifically includes:

[0272] According to the structural thickness of each layer between the electronic device and the heat dissipation element, the thermal conductivity coefficient of each layer and the area of ​​each layer, the thermal conduction resistance from the electronic device to the heat dissipation element is calculated as: Among them, R1,cond is the thermal conduction resistance, δ i is the structural thickness of the i-th layer, λ i is the thermal conductivity of the i-th layer, A i is the area of ​​the i-th layer, and n is the number of layers;

[0273] The wall temperature of the heat dissipation element in contact with water is calculated as: T wall =T e -Q1·R 1,cond , where T wall is the wall temperature, T e is the temperature of the electronic device, Q1 is the first heat dissipation, R 1,cond is the thermal conduction thermal resistance;

[0274] The estimated water temperature at the waterway inlet is: Among them, T in is the water temperature at the water channel inlet, α is the water heat transfer coefficient, is the water mass flow rate, Cp w is the specific heat of water at constant pressure, A w is the water heat transfer area, T w is the average water exchange temperature, T wall is the wall temperature.

[0275] In one embodiment, the water temperature at the end of the water path of the heat dissipating element also includes the water temperature at the water path outlet, and the estimating the water temperature at the end of the water path of the heat dissipating element according to the average water exchange water temperature specifically includes:

[0276] The estimated water temperature at the waterway outlet is: Among them, T out is the water temperature at the water channel outlet, R is the heat exchange area per unit length, and L is the water channel length.

[0277] Regarding the device in the above embodiment, the specific manner in which each module performs operations has been described in detail in the embodiment of the method, and will not be elaborated here.

[0278] like Figure 8 The figure shows a hardware structure diagram of an electronic device of the present invention, including:

[0279] at least one processor 801; and,

[0280] A memory 802 is communicatively connected to at least one of the processors 801; wherein,

[0281] The memory 802 stores instructions that can be executed by at least one of the processors. The instructions are executed by at least one of the processors so that the at least one of the processors can execute the water temperature estimation method as described above.

[0282] Figure 8 A processor 801 is taken as an example.

[0283] The electronic device may further include: an input device 803 and a display device 804 .

[0284] The processor 801, the memory 802, the input device 803 and the display device 804 may be connected via a bus or other means, and the figure takes the connection via a bus as an example.

[0285] The memory 802 is a non-volatile computer-readable storage medium that can be used to store non-volatile software programs, non-volatile computer executable programs and modules, such as program instructions / modules corresponding to the water temperature estimation method in the embodiment of the present application, for example, Figure 1 , Figure 2 The processor 801 executes various functional applications and data processing by running the non-volatile software programs, instructions and modules stored in the memory 802, that is, the water temperature estimation method in the above embodiment is implemented.

[0286] The memory 802 may include a program storage area and a data storage area, wherein the program storage area may store an operating system, an application required by at least one function; the data storage area may store data created according to the use of the water temperature estimation method, etc. In addition, the memory 802 may include a high-speed random access memory, and may also include a non-volatile memory, such as at least one disk storage device, a flash memory device, or other non-volatile solid-state storage device. In some embodiments, the memory 802 may optionally include a memory remotely arranged relative to the processor 801, and these remote memories may be connected to the device for executing the water temperature estimation method via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0287] The input device 803 can receive user clicks and generate signal inputs related to user settings and function controls of the water temperature estimation method. The display device 804 can include display devices such as a display screen.

[0288] The one or more modules are stored in the memory 802 , and when executed by the one or more processors 801 , the water temperature estimation method in any of the above method embodiments is executed.

[0289] According to the present invention, when the current stage of the electronic device is a steady-state stage, the steady-state heat transfer ratio at the current temperature sampling moment is calculated according to the first temperature difference between the temperature of the circuit board at the current temperature sampling moment and the temperature of the previous temperature sampling moment. The steady-state heat transfer ratio is the heat transfer distribution ratio of the electronic device to the heat dissipation element and to the circuit board in the steady-state stage; the first heat dissipation amount of the electronic device to the heat dissipation element under the heating electric power and the second heat dissipation amount of the electronic device to the circuit board are calculated according to the steady-state heat transfer ratio, and the water temperature at the end of the water path in the heat dissipation element is estimated according to the first heat dissipation amount and the second heat dissipation amount. Therefore, the present invention calculates the steady-state heat transfer ratio, and based on the steady-state heat transfer ratio, obtains the accurate first heat dissipation amount of the electronic device to the heat dissipation element under the heating electric power in the steady-state stage, and the accurate second heat dissipation amount of the electronic device to the circuit board, thereby replacing the water temperature sensor with an algorithm to reduce costs and estimate the accurate water temperature at the end of the water path of the heat dissipation element when the electronic device is in the steady-state stage.

[0290] An embodiment of the present invention provides a storage medium, wherein the storage medium stores computer instructions. When a computer executes the computer instructions, the storage medium is used to execute all steps of the water temperature estimation method as described above.

[0291] In the context of the present disclosure, a storage medium may be a tangible medium that may contain or store a program for use by or in conjunction with an instruction execution system, device, or apparatus. The storage medium may be a machine-readable signal medium or a machine-readable storage medium. Alternatively, the storage medium may be a non-temporary computer-readable storage medium, for example, a non-temporary computer-readable storage medium may be a ROM, a random access memory (Random Access Memory, RAM), a compact disc read-only memory (Compact Disc ROM, CD-ROM), a magnetic tape, a floppy disk, and an optical data storage device, etc.

[0292] An embodiment of the present invention provides a vehicle, including the water temperature estimation device as described above, or the electronic device as described above. It is understandable that the vehicle may also include: a processor, a memory, and a computer program. The computer program is stored in the memory and is configured to be executed by the processor to implement the water temperature estimation method provided in the embodiment of the present disclosure. The processor and the memory are already in Figure 8 The parts described in the illustrated embodiment are not repeated here.

[0293] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A water temperature estimation method, characterized in that: include: Acquiring the heating power of the electronic device and the temperature of the circuit board; the electronic device is fixed on the circuit board, and the electronic device is connected to a heat dissipation element in contact with the water channel; When the current stage of the electronic device is a steady-state stage, the steady-state heat transfer ratio at the current temperature sampling moment is calculated according to the first temperature difference between the temperature of the circuit board at the current temperature sampling moment and the temperature of the previous temperature sampling moment, and the steady-state heat transfer ratio is the heat transfer distribution ratio of the electronic device to the heat dissipation element and to the circuit board in the steady-state stage; Calculate, according to the steady-state heat transfer ratio, a first heat dissipation amount of heat dissipated by the electronic device to the heat dissipation element under the heating electric power, and a second heat dissipation amount of heat dissipated by the electronic device to the circuit board; The water temperature at the end of the water path of the heat dissipating element is estimated according to the first heat dissipation and the second heat dissipation.

2. The water temperature estimation method according to claim 1, characterized in that: The method further comprises: When the electronic device is powered on, if the absolute value of the second temperature difference between the circuit board temperature and the ambient temperature is less than the preset second state judgment value, and the absolute value of the first temperature difference is less than the preset first state judgment value, then the current stage of the electronic device is judged to be the steady state stage, otherwise, the current stage of the electronic device is judged to be the cold start stage; When the electronic device is powered off, the current stage of the electronic device is cleared.

3. The water temperature estimation method according to claim 1, characterized in that: The calculating the steady-state heat transfer ratio at the current temperature sampling moment according to the first temperature difference between the temperature of the circuit board at the current temperature sampling moment and the temperature at the previous temperature sampling moment specifically includes: Calculate the steady-state heat transfer ratio at the current temperature sampling moment as: Among them, R is the steady-state heat transfer ratio, R0 is the steady-state heat transfer reference ratio, dT is the first temperature difference, k1 is the coefficient of the first steady-state heat transfer ratio relationship formula, k2 is the coefficient of the second steady-state heat transfer ratio relationship formula, and e is a natural constant.

4. The water temperature estimation method according to claim 1, characterized in that: The calculating, according to the steady-state heat transfer ratio and the heating electric power, a first heat dissipation amount of heat dissipated by the electronic device to a heat dissipation element connected to the electronic device, and a second heat dissipation amount of heat dissipated by the electronic device to the circuit board specifically includes: The first heat dissipation is calculated as: Q1=(1-R)Q, and the second heat dissipation is calculated as: Q2=RQ, wherein Q1 is the first heat dissipation, Q2 is the second heat dissipation, Q is the heat generation per unit time of the electronic device calculated based on the heat generation electric power, and R is the steady-state heat transfer ratio.

5. The water temperature estimation method according to claim 1, characterized in that: The estimating the water temperature at the end of the water path of the heat dissipation element according to the first heat dissipation and the second heat dissipation specifically includes: Calculate the temperature of the electronic device at the location of the electronic device according to the second heat dissipation and the circuit board temperature and based on the second thermal resistance between the temperature measurement point and the electronic device; According to the temperature of the electronic device and the first heat dissipation amount, based on the first thermal resistance between the electronic device and the water path, an average heat exchange water temperature in a heat dissipation element connected to the electronic device is calculated, the average heat exchange water temperature being an average value of the heat exchange temperatures between the heat dissipation element and the electronic device; The water temperature at the end of the water path of the heat dissipating element is estimated according to the average water exchange water temperature.

6. The water temperature estimation method according to claim 5, characterized in that: The calculating the temperature of the electronic device at the location of the electronic device based on the second heat dissipation and the circuit board temperature and based on the second thermal resistance between the temperature measurement point and the electronic device specifically includes: calculating the second thermal resistance between the temperature measurement point and the electronic device as: Where R2 is the second thermal resistance, L2 is the temperature measurement distance from the temperature measurement point to the middle of the electronic device, L1 is the radius of the electronic device, δ is the thickness of the circuit board, λ PCB is the thermal conductivity of the circuit board; Calculate the temperature of the electronic device as: T e =T2+Q2·R2, where T e is the temperature of the electronic device, T2 is the temperature of the circuit board, Q2 is the second heat dissipation, and R2 is the second thermal resistance; The calculating, based on the temperature of the electronic device and the first heat dissipation amount and the first thermal resistance between the electronic device and the water path, the average water exchange temperature in the heat dissipation element connected to the electronic device specifically includes: calculating the average water exchange temperature as: T w =T e -R1·Q1, where T w is the average water exchange temperature, T e is the temperature of the electronic device, R1 is the first thermal resistance, and Q1 is the first heat dissipation.

7. The water temperature estimation method according to claim 5, characterized in that: The water temperature at the end of the water channel of the heat dissipating element includes the water temperature at the water channel inlet, and the estimating the water temperature at the end of the water channel of the heat dissipating element according to the average water exchange water temperature specifically includes: According to the structural thickness of each layer between the electronic device and the heat dissipation element, the thermal conductivity coefficient of each layer and the area of ​​each layer, the thermal conduction resistance from the electronic device to the heat dissipation element is calculated as: Among them, R 1,cond is the thermal conduction resistance, δ i is the structural thickness of the i-th layer, λ i is the thermal conductivity of the i-th layer, A i is the area of ​​the i-th layer, and n is the number of layers; The wall temperature of the heat dissipation element in contact with water is calculated as: T wall =T e -Q1·R 1,cond , where T wall is the wall temperature, T e is the temperature of the electronic device, Q1 is the first heat dissipation, R 1,cond is the thermal conduction thermal resistance; The estimated water temperature at the waterway inlet is: Among them, T in is the water temperature at the water channel inlet, α is the water heat transfer coefficient, is the water mass flow rate, Cp w is the specific heat of water at constant pressure, A w is the water heat transfer area, T w is the average water exchange temperature, T wall is the wall temperature.

8. The water temperature estimation method according to claim 7, characterized in that: The water temperature at the end of the water path of the heat dissipating element also includes the water temperature at the water path outlet. The estimating the water temperature at the end of the water path of the heat dissipating element according to the average water exchange water temperature specifically includes: The estimated water temperature at the waterway outlet is: Among them, T out is the water temperature at the water channel outlet, R is the heat exchange area per unit length, and L is the water channel length.

9. A water temperature estimation device, characterized in that: include: An acquisition module is used to acquire the heating power of the electronic device and the temperature of the circuit board; the electronic device is fixed on the circuit board, and the electronic device is connected to a heat dissipation element in contact with the water channel; a steady-state heat transfer ratio calculation module, for calculating the steady-state heat transfer ratio at the current temperature sampling moment when the current stage of the electronic device is the steady-state stage, according to a first temperature difference between the temperature of the circuit board at the current temperature sampling moment and the temperature of the previous temperature sampling moment, wherein the steady-state heat transfer ratio is a heat transfer distribution ratio of the electronic device to the heat dissipation element and to the circuit board in the steady-state stage; a heat dissipation calculation module, used for calculating a first heat dissipation of the electronic device to the heat dissipation element under the heating electric power and a second heat dissipation of the electronic device to the circuit board according to the steady-state heat transfer ratio; A water temperature calculation module at the end of the water channel is used to estimate the water temperature at the end of the water channel of the heat dissipation element according to the first heat dissipation and the second heat dissipation.

10. An electronic device, characterized in that: include: at least one processor; as well as, a memory communicatively connected to at least one of the processors; wherein, The memory stores instructions that can be executed by at least one of the processors, and the instructions are executed by at least one of the processors to enable the at least one processor to execute the water temperature estimation method according to any one of claims 1 to 8.

11. A storage medium, characterized in that: The storage medium stores computer instructions, and when a computer executes the computer instructions, it is used to execute all steps of the water temperature estimation method according to any one of claims 1 to 8.

12. A vehicle, characterized in that: It includes the water temperature estimation device as claimed in claim 9, or the electronic device as claimed in claim 10.

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