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

Abstract

The application discloses a water temperature estimation method and device, electronic equipment, a storage medium and a vehicle. The method comprises the following steps: obtaining the heat generation electric power of an electronic device and the temperature of a circuit board; the electronic device is fixed on the circuit board, and the electronic device is connected with a heat dissipation element in contact with a water channel; when the current stage of the electronic device is a steady state stage, a steady state heat transfer proportion of a current temperature sampling time is calculated according to a first temperature difference between the temperature of the circuit board at the current temperature sampling time and the temperature of the circuit board at a previous temperature sampling time; a first heat dissipation amount of the electronic device to the heat dissipation element under the heat generation electric power and a second heat dissipation amount of the electronic device to the circuit board are calculated according to the steady state heat transfer proportion; and the water end water temperature of the heat dissipation element is estimated according to the first heat dissipation amount and the second heat dissipation amount. According to the application, the steady state heat transfer proportion is calculated, the proportion of heat dissipation of the electronic device under different conditions is considered, and therefore the water end water temperature of the electronic device in the steady state stage is more accurate.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of vehicles, and particularly relates to a water temperature estimation method and device, electronic equipment, storage medium and vehicle. BACKGROUND

[0002] When heat dissipation is performed on an electronic device, such as a chip, a temperature sensor is usually arranged to measure the temperature of the electronic device for monitoring the temperature of the electronic device. In addition, the electronic device is 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, such as the outlet water temperature and the inlet water temperature of the water circuit, the water temperature in the water circuit needs to be monitored.

[0004] In order to reduce the cost, the water circuit end water temperature of the heat dissipation element connected to the electronic device can be determined through a thermal resistance model of the electronic device, so as to reduce the use of the water temperature sensor.

[0005] However, the heat dissipation condition of the electronic device changes when the electronic device is in different working states. For example, when in a steady state stage, the upstream water temperature in the water circuit of the heat dissipation element changes, which causes the heat transfer condition of the electronic device to the heat dissipation element and the circuit board to change. However, the prior art does not consider this condition, so that the existing thermal resistance model is not accurate enough when estimating the water circuit end water temperature. SUMMARY

[0006] Therefore, it is necessary to provide a water temperature estimation method, device, electronic equipment, storage medium and vehicle to solve the problem of inaccurate water circuit end water temperature estimation of the prior art when the electronic device is in a steady state stage.

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

[0008] obtaining the heat generation electric power of an electronic device and the temperature of a 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 a water circuit;

[0009] when the current stage of the electronic device is a steady state stage, calculating a steady state heat transfer proportion of a current temperature sampling time according to a first temperature difference of the circuit board temperature between the current temperature sampling time and a previous temperature sampling time, the steady state heat transfer proportion being a heat transfer distribution proportion of the electronic device to the heat dissipation element and to the circuit board for heat dissipation in the steady state stage;

[0010] calculating a first heat dissipation amount of the electronic device to the heat dissipation element for heat dissipation under the heat generation electric power and a second heat dissipation amount of the electronic device to the circuit board for heat dissipation according to the steady state heat transfer proportion;

[0011] estimate the water temperature at the waterway end of the heat dissipation element according to the first heat dissipation amount and the second heat dissipation amount.

[0012] Further, 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, it is judged that the current stage of the electronic device is a steady state stage, otherwise it is judged that the current stage of the electronic device is a cold start stage.

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

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

[0016] The steady state heat transfer ratio at the current temperature sampling time is calculated as:

[0017] Wherein, 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 first steady state heat transfer ratio relationship coefficient, k2 is the second steady state heat transfer ratio relationship coefficient, and e is the natural constant.

[0018] Further, the first heat dissipation amount of the electronic device to the heat dissipation element connected with the electronic device 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 electric power, specifically including:

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

[0020] Further, the water temperature at the waterway end of the heat dissipation element is estimated according to the first heat dissipation amount and the second heat dissipation amount, specifically including:

[0021] According to the second heat dissipation amount and the circuit board temperature, the electronic device temperature at the location of the electronic device is calculated based on the second thermal resistance between the temperature measurement point and the electronic device.

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

[0023] According to the average heat exchange water temperature, a water path end water temperature of the heat dissipation element is estimated.

[0024] Further more,

[0025] According to the second heat dissipation amount and the circuit board temperature, and based on a second thermal resistance between the temperature measuring point and the electronic device, an electronic device temperature at a position of the electronic device is calculated, specifically including: the second thermal resistance between the temperature measuring point and the electronic device is calculated as:

[0026] wherein R2 is the second thermal resistance, L2 is a temperature measuring distance between the temperature measuring point and the electronic device, L1 is a radius of the electronic device, δ is a thickness of the circuit board, λ PCB is a thermal conductivity coefficient of the circuit board;

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

[0028] According to the electronic device temperature, the first heat dissipation amount, and based on a first thermal resistance between the electronic device and the water path, an average heat exchange water temperature in a heat dissipation element connected with the electronic device is calculated, the average heat exchange water temperature being an average of heat exchange temperatures of the heat dissipation element and the electronic device; w = T e - R1·Q1, wherein T w is the average heat exchange water temperature, T e is the electronic device temperature, R1 is the first thermal resistance, and Q1 is the first heat dissipation amount.

[0029] Further more, the water path end water temperature of the heat dissipation element includes a water path inlet water temperature, and according to the average heat exchange water temperature, the water path end water temperature of the heat dissipation element is estimated, specifically including:

[0030] According to structural thicknesses of each layer between the electronic device and the heat dissipation element, thermal conductivity coefficients of each layer, and areas of each layer, a thermal conduction thermal resistance between the electronic device and the heat dissipation element is calculated as: wherein R 1,cond is the thermal conduction thermal resistance, δ iis the structure thickness of the i-th layer, λ i is the heat conduction coefficient of the i-th layer, A i is the area of the i-th layer, 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 , wherein T wall is the wall temperature, T e is the electronic device temperature, Q1 is the first heat dissipation amount, R 1,cond is the heat conduction thermal resistance;

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

[0033] Further, the water channel end water temperature of the heat dissipation element also includes the water channel outlet water temperature, and the water channel end water temperature of the heat dissipation element is estimated according to the average heat exchange water temperature, specifically comprising:

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

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

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

[0037] A steady-state heat transfer proportion calculation module is configured to, when the current stage of the electronic device is a steady-state stage, calculate a steady-state heat transfer proportion at a current temperature sampling time according to a first temperature difference of the temperature of the circuit board at the current temperature sampling time and at a previous temperature sampling time; the steady-state heat transfer proportion is a heat transfer distribution proportion of the electronic device to the heat dissipation element and to the circuit board for heat dissipation in the steady-state stage;

[0038] A heat dissipation amount calculation module is configured to calculate, according to the steady-state heat transfer proportion, a first heat dissipation amount of the electronic device to the heat dissipation element for heat dissipation under the heat generation electric power and a second heat dissipation amount of the electronic device to the circuit board for heat dissipation.

[0039] a waterway end water temperature calculation module configured to estimate a waterway end water temperature of the heat dissipation element according to the first heat dissipation amount and the second heat dissipation amount.

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

[0041] at least one processor; and,

[0042] a memory in communication with the at least one processor; wherein,

[0043] the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the water temperature estimation method as described above.

[0044] The present application provides a storage medium storing computer instructions, when the computer executes the computer instructions, all steps of the water temperature estimation method as described above are performed.

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

[0046] The present application calculates a steady-state heat transfer ratio at a current temperature sampling time according to a first temperature difference of the circuit board temperature between the current temperature sampling time and a previous temperature sampling time when the electronic device is in a current stage of a steady state, the steady-state heat transfer ratio being a heat transfer distribution ratio of the electronic device to the heat dissipation element and to the circuit board in the steady state; calculates a first heat dissipation amount of the electronic device to the heat dissipation element and a second heat dissipation amount of the electronic device to the circuit board according to the steady-state heat transfer ratio under the heating electric power, and estimates a waterway end water temperature in the heat dissipation element according to the first heat dissipation amount and the second heat dissipation amount. Therefore, the present application considers that the heat transfer ratio of the electronic device to the outside is different under different conditions, calculates the steady-state heat transfer ratio, and obtains the first heat dissipation amount of the electronic device to the heat dissipation element and the second heat dissipation amount of the electronic device to the circuit board under the heating electric power in the steady state based on the steady-state heat transfer ratio, so as to make the waterway end water temperature of the electronic device in the steady state more accurate. BRIEF DESCRIPTION OF DRAWINGS

[0047] Figure 1 A workflow diagram of a water temperature estimation method according to an embodiment of the present application;

[0048] Figure 2 A workflow diagram of a water temperature estimation method according to another embodiment of the present application;

[0049] Figure 3 A schematic diagram of a heat conduction model for an embodiment of the present application;

[0050] Figure 4 A working flow chart for determining a current stage of an electronic device for an embodiment of the present application;

[0051] Figure 5 A schematic diagram of a water flow model for an embodiment of the present application;

[0052] Figure 6 A schematic diagram of a calculation result for an embodiment of the present application;

[0053] Figure 7 A schematic diagram of a water temperature estimation device for an embodiment of the present application;

[0054] Figure 8 A schematic diagram of a hardware structure of an electronic device according to the present application. DETAILED DESCRIPTION

[0055] The specific embodiments of the present application will be further described below with reference to the accompanying drawings. Identical parts are denoted by identical reference numerals in the drawings. It should be noted that the words "front", "back", "left", "right", "up" and "down" used in the following description refer to the directions in the drawings, and the words "inner" and "outer" refer to the directions towards or away from the geometric center of a particular part.

[0056] As Figure 1 shown is a working flow chart of a water temperature estimation method for an embodiment of the present application, comprising:

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

[0058] Step S102, when a current stage of the electronic device is a steady state stage, calculating a steady state heat transfer proportion of a current temperature sampling time according to a first temperature difference of the temperature of the circuit board at the current temperature sampling time and at a previous temperature sampling time; the steady state heat transfer proportion is a heat transfer distribution proportion of the electronic device to the heat dissipation element and to the circuit board for heat dissipation in the steady state stage;

[0059] Step S103, calculating a first heat dissipation amount of the electronic device to the heat dissipation element for heat dissipation and a second heat dissipation amount of the electronic device to the circuit board for heat dissipation according to the steady state heat transfer proportion;

[0060] Step S104, estimating a water temperature at an end portion of the heat dissipation element according to the first heat dissipation amount and the second heat dissipation amount.

[0061] Specifically, the present invention can be applied to electronic devices with processing capabilities, such as electronic control units (ECUs) or extended domain control units (XCUs) in vehicles.

[0062] Specifically, the electronic device first performs 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 diagram shown illustrates a heat conduction model according to 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 electrical power generated by the electronic device 1, which is entirely converted into heat since it does not require external work. Connected to the electronic device 1 is the circuit board 2 (Printed Circuit Board, PCB). Due to the poor thermal conductivity of the circuit board, its heat dissipation to the environment is limited. 环 This is negligible. The heat generated by electronic device 1 is transferred through circuit board 2 and through contacting heat dissipation element 3, which is preferably a heat sink, such as a heat-dissipating aluminum plate. The heat dissipation element contacts the cooling water in the water channel, transferring heat to the cooling water. The water channel refers to the passageway for cooling water flow formed by the heat dissipation element. More than 90% of the heat is dissipated through heat dissipation element 3. Electronic device 1 is connected to heat dissipation element 3 through thermally conductive structure 4. The heat dissipation of electronic device 1 to the water through heat dissipation element 3 is Q. 水 .

[0065] A sensor is installed at temperature measurement point 21 on circuit board 2 to obtain the circuit board temperature. The distance from temperature measurement point 21 to the center of 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 time is calculated based on the first temperature difference between the circuit board temperature at the current temperature sampling time and the previous temperature sampling time.

[0067] The state of the electronic device is in a steady state phase during normal use, and after power-off and re-powering, the electronic device transitions from a cold start phase to a steady state phase. Therefore, by determining whether the electronic device is in a steady state phase, and in the steady state phase, according to the steady state heat transfer proportion relationship, according to the first temperature difference of the circuit board temperature at the current temperature sampling time and the last temperature sampling time, the steady state heat transfer proportion at the current temperature sampling time is determined. The steady state heat transfer proportion is the heat transfer distribution proportion of the electronic device to the heat dissipation element and to the circuit board in the steady state phase.

[0068] Then step S103 is performed, and the first heat dissipation amount of the electronic device to the heat dissipation element and the second heat dissipation amount of the electronic device to the circuit board are calculated according to the steady state heat transfer proportion under the heat generating electric power.

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

[0070] Finally, step S104 is performed, and the water temperature at the end of the water channel of the heat dissipation element is estimated according to the first heat dissipation amount and the second heat dissipation amount based on the steady state heat transfer.

[0071] Specifically, the average heat transfer water temperature is calculated based on the first heat dissipation amount and the second heat dissipation amount calculated in step S103, and the water temperature at the end of the water channel of the heat dissipation element is estimated according to the average heat transfer water temperature. The average heat transfer water temperature is the average of the heat transfer temperatures of the heat dissipation element and the electronic device. Since the water flow in the heat dissipation element flows 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 dissipation element is different from the average heat transfer water temperature. In order to obtain the water temperature at the end of the water channel, the wall temperature of the pipe wall of the heat dissipation element in contact with the water can be calculated according to the average heat transfer water temperature. The steady state heat transfer refers to the temperature distribution of the entire heat transfer system, including the electronic device as the heat source and each heat transfer element for heat dissipation, which does not change, wherein the temperature distribution does not change means that the temperature at each point does not change or changes very little. Under the condition of uniform wall temperature, based on the wall temperature, the relationship between the average heat transfer water temperature and the water temperature at the end of the water channel in the heat dissipation element can be obtained. Thus, the water temperature at the end of the water channel in the heat dissipation element is estimated according to the average heat transfer water temperature.

[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] The application calculates the steady-state heat transfer ratio at the current temperature sampling moment according to the first temperature difference of the circuit board temperature between the current temperature sampling moment and the last temperature sampling moment when the current stage of the electronic device is the steady-state stage, the steady-state heat transfer ratio being the heat transfer distribution ratio of the electronic device to the heat dissipation element and to the circuit board in the steady-state stage; calculates the first heat dissipation amount of the electronic device to the heat dissipation element and the second heat dissipation amount of the electronic device to the circuit board according to the steady-state heat transfer ratio, and estimates the waterway end water temperature in the heat dissipation element according to the first heat dissipation amount and the second heat dissipation amount. Therefore, the application considers that the proportion of the electronic device to the outside heat transfer is different under different conditions, calculates the steady-state heat transfer ratio, and obtains the first heat dissipation amount of the electronic device to the heat dissipation element and the second heat dissipation amount of the electronic device to the circuit board under the heat generating electric power in the steady-state stage based on the steady-state heat transfer ratio, so that the waterway end water temperature of the electronic device in the steady-state stage is more accurate.

[0074] As Figure 2 The working flow chart of a water temperature estimation method in another embodiment of the application is shown in the figure, which includes:

[0075] Step S201, obtaining the heat generating electric power of the electronic device and the circuit board temperature; the electronic device is fixed on the circuit board, and the electronic device is connected with the heat dissipation element in contact with the waterway.

[0076] Step S202, 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 environment temperature is less than a preset second state judgment value, it is judged that the current stage of the electronic device is the steady-state stage, otherwise it is judged that the current stage of the electronic device is 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 the steady-state stage, calculating the steady-state heat transfer ratio at the current temperature sampling moment according to the first temperature difference of the circuit board temperature between the current temperature sampling moment and the last temperature sampling moment, the steady-state heat transfer ratio being 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 calculation of the steady-state heat transfer ratio at the current temperature sampling moment according to the first temperature difference of the circuit board temperature between the current temperature sampling moment and the last temperature sampling moment specifically includes:

[0079] The calculation of the steady-state heat transfer ratio at the current temperature sampling moment is:

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

[0081] In step S204, a first heat dissipation amount of the electronic device to the heat dissipation element under the heat generating electric power and a second heat dissipation amount of the electronic device to the circuit board are calculated according to the steady-state heat transfer ratio.

[0082] In one embodiment, the calculation of the first heat dissipation amount of the electronic device to the heat dissipation element under the heat generating electric power and the second heat dissipation amount of the electronic device to the circuit board specifically includes:

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

[0084] In step S205, an electronic device temperature at the location of the electronic device is calculated according to the second heat dissipation amount and the circuit board temperature based on a second thermal resistance between the temperature measuring point and the electronic device.

[0085] In one embodiment, the calculation of the electronic device temperature at the location of the electronic device according to the second heat dissipation amount and the circuit board temperature based on the second thermal resistance between the temperature measuring point and the electronic device specifically includes:

[0086] wherein R2 is the second thermal resistance, L2 is a temperature measuring distance between the temperature measuring point and the electronic device, L1 is a radius of the electronic device, δ is a thickness of the circuit board, and λ PCB is a thermal conductivity coefficient of the circuit board.

[0087] The electronic device temperature is calculated as T e =T2+Q2·R2, wherein T e is the electronic device temperature, T2 is the circuit board temperature, Q2 is the second heat dissipation amount, and R2 is the second thermal resistance.

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

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

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

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

[0092] Calculating a thermal conduction thermal resistance between the electronic device and the heat dissipation element according to structural thicknesses of layers between the electronic device and the heat dissipation element, thermal conduction coefficients of the layers, and areas of the layers as R 1,cond = ∑(δ i i·λ i i·A i i), where R 1,cond is the thermal conduction thermal resistance, δ i is the structural thickness of the i-th layer, λ i is the thermal conduction coefficient of the i-th layer, A i is the area of the i-th layer, and n is the number of layers.

[0093] Calculating a wall temperature of the heat dissipation element in contact with water as T wall = T e - Q1·R 1,cond , where T wall is the wall temperature, T e is the electronic device temperature, Q1 is the first heat dissipation amount, and R 1,cond is the thermal conduction thermal resistance.

[0094] Estimating the water path inlet water temperature as T in = T w - (α·Cp w ·A w ·Q wall ), where T in is the water path inlet water temperature, α is a water heat exchange coefficient, is a water mass flow, Cp w is a water specific heat at constant pressure, A w is a water heat exchange area, and T w is the wall temperature.w T is the average heat exchange water temperature, T wall is the wall temperature.

[0095] In one embodiment, the water temperature at the water channel end of the heat dissipation element further includes a water channel outlet water temperature, and the water temperature at the water channel end of the heat dissipation element is estimated according to the average heat exchange water temperature, specifically comprising:

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

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

[0098] Then, step S202 is performed 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 time and the last temperature sampling time is less than a preset first state determination value, and the absolute value of the second temperature difference between the circuit board temperature and the environment temperature is less than a preset second state determination value, it is determined that the current stage of the electronic device is a steady state stage, otherwise it is determined that the current stage of the electronic device is a cold start stage; while the electronic device is powered off, the current stage of the electronic device is cleared.

[0099] Wherein, after the electronic device is powered on, the electronic device first experiences a cold start stage, and the temperature rises rapidly. Then the temperature reaches a steady state, dT = 0, and enters a steady state stage and remains, in the steady state stage, the temperature may have slight fluctuations, wherein, dT = 0 is a steady state condition, 0 < | dT | < T 阈值 is a quasi-steady state condition, and 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 according to the temperature.

[0100] In some embodiments, the first state determination value is the absolute value of the temperature difference of the circuit board temperature at two consecutive temperature sampling times in the steady state condition, and the second quantile, for example, the 95% quantile, in the large data. The second state determination value is the absolute value of the temperature difference between the circuit board temperature and the environment temperature in the steady state condition, and the first quantile, for example, the 20% quantile, in the large data.

[0101] Specifically, as shown in Figure 4 the working flow chart for determining the current stage of the electronic device in the best embodiment of the present application, the electronic device is a chip, and the method comprises:

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

[0103] Step S402, the chip is in hibernation;

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

[0105] Step S404, if |T2-T 环 If |T2-T

[0106] Wherein, Limit1 is a preset first state judgment value, Limit2 is a preset second state judgment value, wherein, Limit1 is set as the 95th percentile of the absolute value of the temperature difference of the circuit board temperature at two continuous temperature sampling moments under the steady state condition in the large data, and Limit2 is set as the 20th percentile of the absolute value of the temperature difference between the circuit board temperature measurement value and the environment temperature under the steady state condition in the large data.

[0107] Wherein, T2 is the circuit board temperature, T 环 The absolute value of the temperature difference between the circuit board temperature and the environment 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 judged as the cold start state, and in the whole process of the cold start, Tx is compared with the circuit board temperature at each temperature sampling moment to determine whether the current stage still remains the cold start stage.

[0108] Then, when the current stage of the electronic device is the steady state stage, step S203 is performed, and the steady state heat transfer proportion at the current temperature sampling moment is calculated according to the first temperature difference of the circuit board temperature between the current temperature sampling moment and the last temperature sampling moment, the steady state heat transfer proportion is the heat transfer distribution proportion of the electronic device to the heat dissipation element and to the circuit board under the steady state stage.

[0109] In one embodiment, the steady state heat transfer proportion at the current temperature sampling moment is calculated according to the first temperature difference of the circuit board temperature between the current temperature sampling moment and the last temperature sampling moment, specifically including:

[0110] The steady state heat transfer proportion at the current temperature sampling moment is calculated as:

[0111] R = k1 * e k2 * dT + R0, wherein R is the steady-state heat transfer ratio, R0 is a steady-state heat transfer reference ratio, dT is a first temperature difference of the circuit board temperature at a current temperature sampling time and a previous temperature sampling time, k1 is a first steady-state heat transfer ratio relationship formula coefficient, k2 is a second steady-state heat transfer ratio relationship formula coefficient, and e is a natural constant.

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

[0113]

[0114] R = k1 * e k2 * dT + R0, wherein R is the steady-state heat transfer ratio, R0 is a steady-state heat transfer reference ratio, dT is a first temperature difference of the circuit board temperature at a current temperature sampling time and a previous temperature sampling time, k1 is a first steady-state heat transfer ratio relationship formula coefficient, k2 is a second steady-state heat transfer ratio relationship formula 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 a chip-aluminum plate steady-state heat transfer reference ratio, which is set as R0 = 0.9.

[0116] The embodiment provides a steady-state heat transfer ratio relationship. The first steady-state heat transfer ratio relationship formula coefficient k1 in formula (1) represents a proportional relationship between dR and dT, that is, a larger dT will cause a larger dR. The second steady-state heat transfer ratio relationship formula coefficient k2 represents a scaling coefficient of dT, which can fit the speed of change of R with dT in dynamic change, that is, the size of temperature transfer capability. The right side of formula (1) uses a sigmoid function, on the one hand, the exponential function is more in line with the change law of heat conduction, and on the other hand, it makes R tend to saturation with the increase of dT, avoiding the change of too large R caused by too large dT due to error interference and other factors.

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

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

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

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

[0121] Step S206, according to the electronic device temperature, the first heat dissipation amount, based on the first thermal resistance between the electronic device to the waterway, the average heat exchange water temperature in the heat dissipation element connected with the electronic device is calculated.

[0122] In one embodiment, the first heat dissipation amount of the electronic device to the heat dissipation element and the second heat dissipation amount of the electronic device to the circuit board are calculated according to the steady-state heat transfer ratio, specifically comprising:

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

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

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

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

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

[0128] Q2=RQ (3)

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

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

[0131] This embodiment combines the steady-state heat transfer ratio to determine the first heat dissipation amount through the heat dissipation element and the second heat dissipation amount through the circuit board.

[0132] In one embodiment, calculating the electronic device temperature at the location of the electronic device based on the second heat dissipation and the circuit board temperature, and using 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 follows:

[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, and λ PCB The thermal conductivity coefficient of the circuit board;

[0134] The temperature of the electronic device is calculated as: T e =T² + Q²·R², where T e T1 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 the temperature distribution from the center of the electronic device to the circuit board follows a circular distribution in 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, i.e., the electrical power of the electronic device's heat generation. R is the radial distance of the chip, δ is the thickness of the circuit board, λ is the thermal conductivity coefficient, and A is the heat transfer area. PCB It is the thermal conductivity coefficient of the circuit board. The second thermal resistance between the temperature measurement point and the electronic device can be obtained by integrating equation (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, and λ PCB The thermal conductivity coefficient of the circuit board is denoted as .

[0140] Then, in the steady-state phase, the temperature of the electronic device can be calculated from the device temperature relationship, i.e., formula (6):

[0141] T e =T2+Q2·R2 (6)

[0142] Among them, T e T1 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 uses a second thermal resistance to determine the accurate temperature of electronic devices.

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

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

[0146] T w =T e -R1·Q1 (7)

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

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

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

[0150] 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, the thermal resistance of the electronic device to the heat dissipation element is calculated. The electronic device is connected to the heat dissipation element through one or more thermally conductive structures. The layer includes multiple structural layers within the electronic device, one or more of the thermally conductive structures, and the heat dissipation element.

[0151] Calculate the convective heat transfer thermal resistance between the heat dissipation element and the 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 thermal convection resistance, i.e., R1 = R 1,cond +R 1,conv Where R1 is the first thermal resistance, R 1,cond R is the thermal resistance for thermal conduction. 1,conv The convective heat transfer thermal resistance is given.

[0153] Specifically, electronic devices generally consist of multiple structural layers. Taking a chip as an example, the structural layers of a chip typically include: a substrate layer, a solder layer, a substrate layer, a heat source layer, an active region layer, and so on. Each structural layer has its own thickness and area, and depending on the material of different layers, each structural layer has its own thermal conductivity.

[0154] Therefore, the thermal resistance between the electronic device and the heat dissipation element is calculated based on the structural thickness, thermal conductivity coefficient, and area of ​​each layer between the electronic device and the heat dissipation element. Furthermore, the layers between the electronic device and the heat dissipation element also include thermally conductive structures and heat dissipation elements. The thermally conductive structures include various existing thermally conductive adhesives and components. Each thermally conductive adhesive or component is considered as a layer. Since the heat dissipation element is generally a flat plate, it is considered as a single layer. The thermal resistance between the electronic device and the heat dissipation element is obtained by calculating the relevant parameters of each layer between the electronic device and the heat dissipation element.

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

[0156] The thermal resistance for heat conduction is calculated as follows: Among them, R 1,cond For the thermal resistance of the heat conduction, δ i Let λ be the structural thickness of the i-th layer. i Let A be the thermal conductivity coefficient of the i-th layer. i Let n be the area of ​​the i-th layer and n be the number of layers.

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

[0158]

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

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

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

[0162] In some embodiments, the heat transfer resistance of the heat dissipation element to water is calculated as: wherein R 1,conv is the heat transfer resistance of the heat dissipation element to water, A w is the water heat transfer area, and a is the water heat transfer coefficient.

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

[0164] The present embodiment calculates the average heat transfer water temperature in the heat dissipation element according to the heat transfer resistance.

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

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

[0167] substituting the steady-state heat transfer proportionality relationship into the heat transfer resistance steady-state model;

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

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

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

[0171] Based on the test values obtained under the test working condition, the deviation between the average heat transfer water temperature output by the trained model and the measured value of the water temperature obtained under the test working condition is globally optimized by least squares to obtain the final k1 and k2.

[0172] The k1 and k2 are brought into formula (1) to form the final dynamic heat transfer resistance model.

[0173] Finally, a step S207 is performed to estimate the water temperature at the water channel end of the heat dissipation element based on the steady-state heat exchange according to the average heat exchange water temperature.

[0174] In particular, the thermal resistance steady-state model outputs an average heat exchange water temperature. Since the water channel sensor is usually arranged at the upstream or downstream, the inlet and outlet water temperatures need to be calculated by the average water temperature. The first step to calculate the water temperature is to calculate the wall temperature of the wall in contact with water.

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

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

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

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

[0179] T wall = T e - Q1·R 1,cond (9)

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

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

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

[0183] The water channel inlet water temperature is estimated as follows: , wherein T in is the water channel inlet water temperature, α is the water heat exchange coefficient, is the water mass flow, Cp w is the water specific heat at constant pressure, A w is the water heat exchange area, and T wT is the average heat exchange water temperature, T wall T is the wall temperature.

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

[0185]

[0186] wherein a is the water heat exchange coefficient, is the water mass flow rate, R is the heat exchange area per unit length, Cp w is the specific heat capacity of water at constant pressure, T0 is the water temperature at position 0, generally taken as the inlet, T L is the water temperature at position L, dT water is the water temperature difference of length differential, dx is the length differential, and L is the water path length. From the inlet to the position of length x is referred to as position x, and the integral from the inlet to position x is:

[0187]

[0188] wherein T x is the temperature at position x, T in is the water inlet temperature of the water path, i.e., the water temperature at position 0 T0.

[0189] The temperature at position x is:

[0190]

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

[0192]

[0193] The water inlet temperature of the water path can be obtained from formula (13):

[0194]

[0195] wherein T in is the water inlet temperature of the water path, a is the water heat exchange coefficient, is the water mass flow rate, Cp w is the specific heat capacity of water at constant pressure, A w is the water heat exchange area, T w is the average heat exchange water temperature, T wall is the wall temperature.

[0196] In one embodiment, the water path end temperature of the heat dissipation element further includes a water path outlet temperature, and the water path end temperature of the heat dissipation element is estimated according to the average heat exchange water temperature, specifically comprising:

[0197] The water path outlet temperature is estimated as: wherein Tout Tout is the water outlet temperature of the water path, R is the heat exchange area per unit length, and L is the length of the water path.

[0198] After obtaining the water inlet temperature of the water path, the water outlet temperature of the water path Tout can be calculated according to formula (12). out Tout is actually the temperature T L Therefore, the water outlet temperature of the water path is:

[0199]

[0200] Tout is the water outlet temperature of the water path. out

[0201] The water path flow model can be built by using an existing physical model.

[0202] In some embodiments, the water path flow model is built by a neural network model to obtain the water mass flow.

[0203] The neural network model is built according to experimental data to obtain physical model data, and then extended from the physical model data.

[0204] Specifically, the water mass flow of the heating element in different states is certain. The heating element is an electronic device as a heat source, so the existing water path flow model building method can be used to build the water path flow model, and the corresponding water mass flow is obtained when the state of the heating element is determined. As shown in Figure 5 First, the experimental data 501 is obtained, then the modeling correction is performed, and the GT Power (engine working process simulation calculation software) model 502 is input, the mapping database 503 is obtained through DoE, 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 water path flow model is built as follows:

[0206] 1. Obtain key flow data in the experiment, correct data such as water pump pressure rise, component pressure drop, and along-the-way loss, build a physical model, and correct according to key experimental data.

[0207] 2. Build a physical model according to experimental data, and extend the experimental data. This step can calculate the branch flow that is not measured in the experiment but is related to the simulation. Specifically, a physical model is built by using the GT Power software. Then, a mapping database is obtained through Design of Experiment (DOE). The mapping database can be regarded as a large number of mapping data corresponding to input-output, and a neural network model can be established.

[0208] ​3. On the basis of the data obtained in step 2, the control quantity in the system is taken as a modeling feature, and the features are extended according to the physical meaning, as shown in Table 1. The extension basis can be the order relationship between the water pump rotating speed and the lift, the temperature and the radiation heat exchange, and the instantaneous energy and the cumulative energy entering the system.

[0209] Control quantity Extended feature Water 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, ∫ engine speed * torque

[0210] On the basis of the extended features, feature screening is performed, and the screening method is based on the generalized radial neural network GRNN of the joint probability distribution.

[0211] The screening process is as follows:

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

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

[0214] 4.3 Enter the iteration process, and the fitting target is changed to the remaining information after fitting the output value by using the features in the selected set, and select the feature with the smallest MSE to enter the selected set;

[0215] 4.4 Iteration in turn until the features in the candidate set are traversed.

[0216] The 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 result, select the first four features that make the GRNN fitting MSE reduce to 0, that is, ensure the accuracy and avoid feature redundancy.

[0218] 6. Randomly divide the data obtained in step 2 into a training set and a test set, establish a neural network model according to the selected features, use K test to obtain the accuracy comparison of the model, and select the best flow model according to the training accuracy and the test accuracy, that is Figure 5 The flow static model.

[0219] 7. Build a steady-state heat exchange model of the heat exchange component in the system, for example, use the steady-state heat exchange model of the present application, or various steady-state heat exchange models in the prior art, and the heat absorbed under the steady-state condition causes the temperature change

[0220]

[0221] The heat sources are the heating elements and the water flow heat exchange, so there are

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

[0223] where Q 吸 is the heat absorbed, C p is the specific heat of the cooling water at constant pressure, is the flow rate of the cooling water, T w is the water temperature, T B is the temperature of the heat generating element, L C is the characteristic length of the heat exchange component, a is the heat exchange coefficient, dA is the differential of the heat exchange area, and dx is the differential of the heat exchange length. By combining formula (16) and formula (17) and integrating from the inlet to the outlet of the heat exchange component, we obtain

[0224]

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

[0226] Because the thermal mass of the heat exchange component is large relative to the heat exchange amount in a unit step, it can be considered that the temperature of the heat exchange component in a unit step does not change.

[0227] 8. The heat exchange coefficient is fitted according to the mass flow rate, and it is ensured that the heat exchange coefficient in the water path is within a reasonable range, and the trend is correct

[0228] 9. The heat exchange heat Q in a unit time step is calculated, the temperature change of the heat exchange component in the step is calculated through formula (16), and the temperature of the heat exchange element is updated when calculating the next step.

[0229] 10. The characteristic length of the heat exchange element is identified through experimental data, the deficiency of the flow rate accuracy is compensated, the flow rate model is calibrated, and the flow rate dynamic model as shown in Figure 5 is obtained. The flow rate dynamic model is a model obtained by adding filtering to the static model of the neural network. According to the flow rate dynamic model, the water mass flow rate of the cooling water in different states of the heat generating element, i.e., the electronic device, can be determined.

[0230] After the water mass flow rate is determined, the water heat exchange 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 exchange coefficient can be determined according to the relationship between the Prandtl number and the Nusselt number.

[0231] The water heat exchange coefficient can be fitted according to the water mass flow rate using a second order polynomial fitting, and the formula is as follows:

[0232]

[0233] wherein, a 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 states, laminar flow state and turbulent flow state, which are distinguished according to the Reynolds number, and the calculation formula of the Reynolds number is:

[0235]

[0236] The calculation formula of the Nusselt number is:

[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. Then the water heat transfer coefficient can be obtained as:

[0239]

[0240] In the formula, Pr is the Prandtl number of water, and f(Re, Pr) is an empirical function for calculating the Nusselt number. Due to the different internal structures of the water path, the Nu calculation under laminar flow, transition state and turbulent flow needs to be identified according to the experimental temperature data.

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

[0242] Obtaining a plurality of experimental data, the experimental data including a measured value of the water inlet temperature of the water path;

[0243] According to the initial value of the Nusselt number, an initial value of the water heat transfer coefficient is obtained, and according to the average heat transfer water temperature and the wall temperature, the water inlet temperature of the heat dissipation element is estimated, specifically, the water inlet temperature of the water path is calculated according to formula (14);

[0244] Adjusting the Nusselt number, thereby adjusting the water heat transfer coefficient, until the estimated water inlet temperature of the water path is consistent with the experimental water inlet temperature of the water path.

[0245] As Figure 6 The calculation effect schematic diagram of one example of the present application is shown in the figure, including the main loop test water temperature curve 61, the uncorrected predicted water temperature curve 62, and the water temperature curve 63 predicted by the method of the present embodiment. The abscissa is time, unit: s, and the ordinate is temperature, unit: ℃. From the effect, it can be seen that the model of the present embodiment after dynamic correction can better predict the water temperature change of electronic devices, such as chips, in the dynamic process.

[0246] The embodiment corrects the water temperature prediction of the heat dissipation element of the electronic device in the steady state stage, and solves the delay problem of the existing prediction method. The embodiment simplifies the heat transfer model of the electronic device, inversely calculates the water inlet temperature through the temperature change of the device, improves the accuracy through correction, reduces the sensor demand, and thus reduces the cost.

[0247] Based on the same inventive concept, as Figure 7 Fig. 1 shows a schematic diagram of a water temperature estimation device according to an embodiment of the present application, which comprises:

[0248] The acquisition module 701 is configured to acquire the heat generation electric 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 with the heat dissipation element in contact with the water path.

[0249] The steady state heat transfer proportion calculation module 702 is configured to, when the current stage of the electronic device is a steady state stage, calculate the steady state heat transfer proportion of the current temperature sampling time according to the first temperature difference of the temperature of the circuit board at the current temperature sampling time and the last temperature sampling time, the steady state heat transfer proportion being the heat transfer distribution proportion of the electronic device to the heat dissipation element and to the circuit board in the steady state stage.

[0250] The heat dissipation amount calculation module 703 is configured to calculate the first heat dissipation amount of the electronic device to the heat dissipation element under the heat generation electric power and the second heat dissipation amount of the electronic device to the circuit board according to the steady state heat transfer proportion.

[0251] The water path end water temperature calculation module 704 is configured to estimate the water path end water temperature of the heat dissipation element according to the first heat dissipation amount and the second heat dissipation amount.

[0252] The present application calculates the steady state heat transfer proportion of the current temperature sampling time according to the first temperature difference of the temperature of the circuit board at the current temperature sampling time and the last temperature sampling time when the current stage of the electronic device is a steady state stage, the steady state heat transfer proportion being the heat transfer distribution proportion of the electronic device to the heat dissipation element and to the circuit board in the steady state stage; calculates the first heat dissipation amount of the electronic device to the heat dissipation element under the heat generation electric power and the second heat dissipation amount of the electronic device to the circuit board according to the steady state heat transfer proportion, and estimates the water path end water temperature of the heat dissipation element according to the first heat dissipation amount and the second heat dissipation amount. Therefore, the present application calculates the steady state heat transfer proportion, and obtains the accurate first heat dissipation amount of the electronic device to the heat dissipation element under the heat generation electric power and the accurate second heat dissipation amount of the electronic device to the circuit board in the steady state stage based on the steady state heat transfer proportion, so as to replace the water temperature sensor through the algorithm, reduce the cost, and estimate the accurate water path end water temperature of the heat dissipation element of the electronic device in the steady state stage.

[0253] In one of the embodiments, the device further comprises a judging module for:

[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 a preset second state judging value, and the absolute value of the first temperature difference is less than a preset first state judging value, it is judged that the current stage of the electronic device is a steady state stage, otherwise it is judged that the current stage of the electronic device is a cold start stage;

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

[0256] In one of the embodiments, the steady state heat transfer ratio at the current temperature sampling moment is calculated according to the first temperature difference between the circuit board temperature at the current temperature sampling moment and the circuit board temperature at the last temperature sampling moment, specifically including:

[0257] The steady state heat transfer ratio at the current temperature sampling moment is calculated as:

[0258] Wherein, 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 first steady state heat transfer ratio relationship formula coefficient, k2 is the second steady state heat transfer ratio relationship formula coefficient, and e is the natural constant.

[0259] In one of the embodiments, the first heat dissipation amount of the electronic device to the heat dissipation element connected to the electronic device 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 electric heat power, specifically including:

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

[0261] In one of the embodiments, the water temperature at the end of the waterway of the heat dissipation element is estimated according to the first heat dissipation amount and the second heat dissipation amount, specifically including:

[0262] The electronic device temperature at the location of the electronic device is calculated according to the second heat dissipation amount and the circuit board temperature, based on the second thermal resistance between the temperature measuring point and the electronic device;

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

[0264] According to the average heat exchange water temperature, a water path end water temperature of the heat dissipation element is estimated.

[0265] In one of the embodiments, the electronic device temperature is calculated according to the second heat dissipation amount and the circuit board temperature, and based on a second thermal resistance between the temperature measuring point and the electronic device.

[0266] The electronic device temperature is calculated according to the second heat dissipation amount and the circuit board temperature, and based on a second thermal resistance between the temperature measuring point and the electronic device, specifically including:

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

[0268] wherein R2 is the second thermal resistance, L2 is a temperature measuring distance between the temperature measuring point and the electronic device, L1 is a radius of the electronic device, δ is a thickness of the circuit board, λ PCB is a thermal conductivity coefficient of the circuit board;

[0269] The electronic device temperature is calculated as: T e = T2 + Q2·R2, wherein T e is the electronic device temperature, T2 is the circuit board temperature, Q2 is the second heat dissipation amount, and R2 is the second thermal resistance.

[0270] The average heat exchange water temperature is calculated according to the electronic device temperature and the first heat dissipation amount, and based on the first thermal resistance between the electronic device and the water path, specifically including: the average heat exchange water temperature is calculated as: T w = T e - R1·Q1, wherein T w is the average heat exchange water temperature, T e is the electronic device temperature, R1 is the first thermal resistance, and Q1 is the first heat dissipation amount.

[0271] In one of the embodiments, the water path end water temperature of the heat dissipation element includes a water path inlet water temperature, and the water path end water temperature of the heat dissipation element is estimated according to the average heat exchange water temperature, specifically including:

[0272] According to structural thicknesses of layers between the electronic device and the heat dissipation element, thermal conductivity coefficients of the layers, and areas of the layers, a thermal conduction thermal resistance between the electronic device and the heat dissipation element is calculated as: wherein R1,cond is the thermal conduction thermal resistance, δ i is the structure thickness of the i-th layer, λ i is the thermal conduction coefficient 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 , wherein T wall is the wall temperature, T e is the electronic device temperature, Q1 is the first heat dissipation amount, and R 1,cond is the thermal conduction thermal resistance.

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

[0275] In one of the embodiments, the water channel end water temperature of the heat dissipation element further includes the water channel outlet water temperature, and the water channel end water temperature of the heat dissipation element is estimated according to the average heat exchange water temperature, specifically including:

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

[0277] As to the device in the above-mentioned embodiments, the specific manner in which each module performs the operation has been described in detail in the embodiments related to the method, and will not be described in detail here.

[0278] As Figure 8 shown is a hardware structure schematic diagram of an electronic device, which includes:

[0279] at least one processor 801; and

[0280] a memory 802 in communication connection with the at least one processor 801; wherein

[0281] the memory 802 stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the water temperature estimation method as described above.

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

[0283] The electronic device can 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 can be connected through a bus or other means, and an example of connection through a bus is taken in the figure.

[0285] The memory 802, as a non-volatile computer readable storage medium, 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 embodiments of the present application, for example, the method flow shown in the figure. 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, implements the water temperature estimation method in the above embodiments. Figure 1 Figure 2

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

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

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

[0289] ​​The application calculates a steady-state heat transfer ratio at a current temperature sampling moment according to a first temperature difference of the circuit board at the current temperature sampling moment and a previous temperature sampling moment when the electronic device is in a current stage of steady state, the steady-state heat transfer ratio being a heat transfer distribution ratio of the electronic device to the heat dissipation element and to the circuit board in the steady state; calculates a first heat dissipation amount of the electronic device to the heat dissipation element and a second heat dissipation amount of the electronic device to the circuit board according to the steady-state heat transfer ratio, and estimates the water temperature at the end of the water circuit in the heat dissipation element according to the first heat dissipation amount and the second heat dissipation amount. Therefore, the application calculates the steady-state heat transfer ratio, and obtains the accurate first heat dissipation amount of the electronic device to the heat dissipation element and the accurate second heat dissipation amount of the electronic device to the circuit board in the steady state under the heating electric power based on the steady-state heat transfer ratio, so as to replace the water temperature sensor by the algorithm, reduce the cost, and estimate the accurate water temperature at the end of the water circuit in the heat dissipation element of the electronic device in the steady state.

[0290] An embodiment of the application provides a storage medium, which stores computer instructions, when a computer executes the computer instructions, all steps of the water temperature estimation method are executed.

[0291] In the context of the present disclosure, the storage medium can be a tangible medium, which can contain or store programs for use by or in connection with an instruction execution system, apparatus or device. The storage medium can be a machine-readable signal medium or a machine-readable storage medium. Alternatively, the storage medium can be a non-transitory computer-readable storage medium, for example, the non-transitory computer-readable storage medium can be a ROM, a random access memory (RAM), a compact disc read-only memory (CD-ROM), a magnetic tape, a floppy disk and an optical data storage device, etc.

[0292] An embodiment of the application provides a vehicle, which comprises the water temperature estimation apparatus or the electronic device. It can be understood that the vehicle can also comprise 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 by the embodiments of the present disclosure. The processor and the memory have been described in the foregoing embodiments, and details are not described herein. Figure 8 The parts described in the foregoing embodiments are not described herein.

[0293] The above embodiments only express several implementation manners of the present application, and the description is more specific and detailed, but it should not be understood as a limitation on the patent scope of the present application. It should be noted that for ordinary skilled persons in the art, without departing from the concept of the present application, several modifications and improvements can be made, which are all within the protection scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. A method for estimating water temperature, characterized in that, include: The heating power of the electronic device and the temperature of the circuit board are obtained; the electronic device is fixed on the circuit board and is connected to a heat dissipation element that is 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 time is calculated based on the first temperature difference between the current temperature sampling time and the previous temperature sampling time of the circuit board. 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. Calculate the first heat dissipation amount of the electronic device to the heat dissipation element under the heat dissipation power, and the second heat dissipation amount of the electronic device to the circuit board, based on the steady-state heat transfer ratio. The water temperature at the water outlet of the heat dissipation element is estimated based on 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 includes: 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 determined to be the steady state stage; otherwise, the current stage of the electronic device is determined to be the cold start stage. Clear the current stage of the electronic device when it is powered off.

3. The water temperature estimation method according to claim 1, characterized in that, The step of calculating the steady-state heat transfer ratio at the current temperature sampling moment based on the first temperature difference between the circuit board temperature at the current temperature sampling moment and the previous temperature sampling moment specifically includes: The steady-state heat transfer ratio at the current temperature sampling moment is calculated as follows: Wherein, 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 formula, k2 is the coefficient of the second steady-state heat transfer ratio formula, and e is the natural constant.

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

5. The water temperature estimation method according to claim 1, characterized in that, The step of estimating the water temperature at the water outlet of the heat dissipation element based on the first heat dissipation and the second heat dissipation specifically includes: Based on the second heat dissipation and the circuit board temperature, and using the second thermal resistance between the temperature measurement point and the electronic device, the temperature of the electronic device at the location of the electronic device is calculated. Based on the temperature of the electronic device, the first heat dissipation, and the first thermal resistance between the electronic device and the water path, the average hot water temperature in the heat dissipation element connected to the electronic device is calculated, where the average hot water temperature is the average of the heat exchange temperatures between the heat dissipation element and the electronic device. The water temperature at the end of the heat dissipation element is estimated based on the average heat exchange water temperature.

6. The water temperature estimation method according to claim 5, characterized in that: The step of calculating the electronic device temperature at the location of the electronic device based on the second heat dissipation and the circuit board temperature, and using 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 follows: 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, and λ PCB The thermal conductivity coefficient of the circuit board; The temperature of the electronic device is calculated as: T e =T² + Q²·R², where T e T1 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 step of calculating the average hot water temperature within the heat dissipation element connected to the electronic device based on the electronic device temperature, the first heat dissipation, and the first thermal resistance between the electronic device and the water path, specifically includes: calculating the average hot water temperature as: T w =T e -R1·Q1, where T w The average water exchange temperature, T e R1 is the temperature of the electronic device, Q1 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 water outlet of the heat dissipation element includes the water inlet temperature. Estimating the water temperature at the water outlet of the heat dissipation element based on the average hot water exchange temperature specifically includes: Based on the structural thickness, thermal conductivity coefficient, and area of ​​each layer between the electronic device and the heat dissipation element, the thermal resistance of the electronic device to the heat dissipation element is calculated as follows: Among them, R 1,cond For the thermal resistance of the heat conduction, δ i Let λ be the structural thickness of the i-th layer. i Let A be the thermal conductivity coefficient of the i-th layer. i Let n be the area of ​​the i-th layer, and n be 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 T wall T is the wall temperature. e The temperature of the electronic device is given by R, Q1 is the first heat dissipation, and R is the first heat dissipation. 1,cond The thermal resistance is the thermal conductivity. The estimated water inlet temperature is: Among them, T in The inlet water temperature is α, and the heat transfer coefficient of the water is α. Cp is the water mass flow rate. w For the specific heat of water at constant pressure, A w For the water heat exchange area, T w The average water exchange temperature, T wall The wall temperature is [value].

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

9. A water temperature estimation device, characterized in that, include: An acquisition module is used to acquire the heating power of electronic devices and the temperature of the circuit board; the electronic devices are fixed on the circuit board and are connected to heat dissipation elements that are in contact with the water channel; The steady-state heat transfer ratio calculation module is used to calculate the steady-state heat transfer ratio at the current temperature sampling time based on the first temperature difference between the circuit board temperature at the current temperature sampling time and the previous temperature sampling time when the current stage of the electronic device is a steady-state stage. 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. The heat dissipation calculation module is used to calculate, based on the steady-state heat transfer ratio, the first heat dissipation amount of the electronic device dissipating heat to the heat dissipation element under the heat dissipation power, and the second heat dissipation amount of the electronic device dissipating heat to the circuit board; The 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 based on 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 to enable at least one of the processors to perform the water temperature estimation method as described in any one of claims 1 to 8.

11. A storage medium, characterized in that, The storage medium stores computer instructions, which, when executed by the computer, are used to perform all the steps of the water temperature estimation method as described in any one of claims 1 to 8.

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

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