Whole vehicle hybrid thermal management method and hybrid thermal management system

Abstract

The application provides a whole vehicle hybrid heat management method and a heat management system, and the heat management method comprises the following steps: constructing a pre-control heat exchange intensity model and a feedback heat exchange intensity model; obtaining the heat source heat load and the measured temperature of the cooling medium in each heat exchange loop, and inputting the pre-control heat exchange intensity model to obtain a heat exchange intensity pre-control value; obtaining the target temperature of the cooling medium in each heat exchange loop, and inputting the feedback heat exchange intensity model to obtain a heat exchange intensity feedback value; respectively calculating the total heat exchange intensity value in each heat exchange loop according to the heat exchange intensity pre-control value and the heat exchange intensity feedback value, adjusting the rotating speed, the pulsation amplitude and the pulsation frequency of the variable frequency pump according to the total heat exchange intensity, and then adjusting the heat exchange coefficient of the cooling medium; and realizing heat exchange according to the cooling medium in each heat exchange loop to perform whole vehicle hybrid heat management. The application adjusts the heat exchange by adjusting the heat exchange coefficient of the cooling medium, effectively reduces the power and volume of the pump and the cooling fan of the system, and avoids the waste of resources.

Description

Technical Field

[0001] This invention belongs to the technical field of automotive thermal management, specifically relating to a hybrid thermal management method and hybrid thermal management system for a vehicle. Background Technology

[0002] In the context of vehicle electrification and hybridization, energy management and thermal management have become the two core technology routes that compete in technological competition. Among them, the high-efficiency and low-energy thermal management system has attracted the attention of relevant scholars because it can maximize the performance of power sources such as batteries and engines within a suitable operating temperature range.

[0003] Automotive engines, automotive batteries, and other power sources release a large amount of heat during the process of converting chemical energy into other forms of energy. If this heat cannot be exchanged with the outside environment in a timely manner, it will greatly affect the working performance of the power source and even lead to power source safety accidents. Therefore, the cooling system in the thermal management system needs to play a significant role in this regard.

[0004] Currently, in order to fully consider the maximum heat dissipation capacity of the cooling system, the cooling fan speed, radiator area, and backup power of the cooling inverter pump are generally increased. However, in most operating conditions, this part of the performance does not need to be utilized, resulting in a waste of resources. In addition, the heat generation time of the existing cooling systems is different, and it is difficult to coordinate the heat between the cooling systems well, resulting in low thermal management efficiency. Summary of the Invention

[0005] Based on this, the present invention provides a vehicle hybrid thermal management method and hybrid thermal management system to solve the problems in the prior art.

[0006] This invention provides a vehicle hybrid thermal management method applied to a vehicle thermal circuit, wherein the vehicle thermal circuit includes at least two heat exchange circuits, each of which is equipped with a variable frequency pump. The vehicle hybrid thermal management method includes:

[0007] Construct a pre-controlled heat transfer intensity model and a feedback heat transfer intensity model;

[0008] The heat load of the heat source and the measured temperature of the cooling medium in each heat exchange loop are obtained respectively. The heat load of the heat source and the measured temperature of the cooling medium are input into the pre-controlled heat exchange intensity model to obtain the pre-controlled value of the heat exchange intensity.

[0009] The target temperature of the cooling medium in each heat exchange loop is obtained, and the measured temperature of the cooling medium and the target temperature of the cooling medium are input into the feedback heat transfer intensity model to obtain the heat transfer intensity feedback value.

[0010] The total heat exchange intensity value in each heat exchange loop is calculated based on the heat exchange intensity pre-control value and the heat exchange intensity feedback value. The speed, pulsation amplitude and pulsation frequency of the variable frequency pump are adjusted based on the total heat exchange intensity value. The heat transfer coefficient of the cooling medium in each heat exchange loop is adjusted based on the pulsation amplitude and the pulsation frequency.

[0011] Heat exchange is achieved using the cooling medium within each heat exchange circuit to perform mixed thermal management of the vehicle.

[0012] Preferably, the pre-controlled heat transfer intensity model includes a pre-controlled heat transfer intensity value table. The step of inputting the heat source heat load and the measured temperature of the cooling medium into the pre-controlled heat transfer intensity model to obtain the pre-controlled heat transfer intensity value specifically includes: querying the pre-controlled heat transfer intensity value table according to the heat source heat load and the measured temperature of the cooling medium to obtain the pre-controlled heat transfer intensity value.

[0013] Preferably, the step of inputting the measured temperature of the cooling medium and the target temperature of the cooling medium into the feedback heat transfer intensity model to obtain the heat transfer intensity feedback value specifically includes: using PI control to calculate the input measured temperature of the cooling medium and the target temperature of the cooling medium to obtain the heat transfer intensity feedback value.

[0014] Preferably, the calculation expression for the PI control is:

[0015] p fdb (t)=k p e(t)+k i ∫e(t)dt+u

[0016] In the formula, e(t) represents the control error, which is the target temperature of the cooling medium minus the measured temperature of the cooling medium, and k p k is the proportional term correction coefficient in the PI control. i U is the correction coefficient for the integral term in the PI control, and u is the basic control quantity.

[0017] Preferably, the step of adjusting the heat transfer coefficient of the cooling medium in each heat exchange circuit according to the pulsation amplitude and the pulsation frequency specifically includes: adjusting the Nusselt coefficient of the cooling medium according to the pulsation amplitude and the pulsation frequency, and adjusting the cooling coefficient of the cooling medium according to the Nusselt coefficient.

[0018] Preferably, the expression for calculating the Nusselt coefficient is:

[0019]

[0020] In the formula, D is the geometric length of the heat transfer surface; λ is the thermal conductivity of the fluid; and h is the heat transfer coefficient of the cooling medium.

[0021] Another aspect of the present invention provides a vehicle hybrid thermal management system using the above-described vehicle hybrid thermal management method, wherein the hybrid thermal management system includes at least: a battery heat exchange circuit, an engine heat exchange circuit, and an air conditioning heat exchange circuit;

[0022] A first heat exchanger is provided between the battery heat exchange circuit and the engine heat exchange circuit, and the cooling medium in the battery heat exchange circuit and the cooling medium in the engine heat exchange circuit exchange heat in the first heat exchanger.

[0023] A second heat exchanger is provided between the battery heat exchange circuit and the air conditioning heat exchange circuit, and the cooling medium in the battery heat exchange circuit and the cooling medium in the engine heat exchange circuit exchange heat in the second heat exchanger.

[0024] Preferably, the battery heat exchange circuit further includes a power battery and a heating device, and the cooling medium in the battery heat exchange circuit passes sequentially through the power battery outlet end, the heating device, the first heat exchanger, the second heat exchanger, and the variable frequency pump back to the power battery inlet end.

[0025] Preferably, the engine heat exchange circuit further includes an engine, a radiator, a variable frequency pump, and a cabin heat source, and the engine heat exchange circuit includes a first circuit and a second circuit;

[0026] The cooling medium in the first circuit passes sequentially through the engine outlet, the radiator, the variable frequency pump, and the cabin heat source back to the engine inlet.

[0027] The cooling medium in the second circuit passes sequentially through the engine outlet, the radiator, the variable frequency pump, and the first heat exchanger before returning to the engine inlet.

[0028] Preferably, the air conditioning heat exchange circuit further includes a compressor, a cabin evaporator, and a variable frequency pump, and the air conditioning heat exchange circuit includes a third circuit and a fourth circuit;

[0029] The cooling medium in the third circuit passes sequentially through the compressor outlet end and the cabin evaporator back to the compressor inlet end;

[0030] The cooling medium in the fourth circuit passes sequentially through the compressor outlet, the second heat exchanger, and the variable frequency pump back to the compressor inlet.

[0031] The beneficial effects of the present invention are as follows: The vehicle hybrid thermal management method in the above embodiments of the present invention, based on the different heat source heat loads, measured temperatures of cooling media, and target temperatures of cooling media in each heat exchange circuit of the vehicle system, calculates the total heat transfer intensity value p for different heat exchange circuits. otoThe difference lies in the total heat transfer intensity value p within different heat exchange loops. oto By adaptively adjusting the speed, pulsation amplitude, and pulsation frequency of the variable frequency pumps in each heat exchange loop, the flow rate and heat transfer coefficient of the cooling medium in each loop change accordingly. This ultimately enables rapid heat exchange between the cooling media in different heat exchange loops, keeping the temperature of each component in each heat exchange loop within a suitable range. Specifically, in this embodiment, the cooling media in different heat exchange loops can exchange heat through heat exchangers. The flow rate and heat transfer coefficient of the cooling media in each cooling loop can be changed according to heat dissipation needs. Under the same heat dissipation effect for the entire vehicle system, compared with the traditional method of increasing the speed of the cooling fan, the area of ​​the radiator, and the backup power of the variable frequency pump, this avoids wasting resources. The cooperation of multiple heat exchange loops can effectively improve the overall thermal management efficiency of the system and has practical application value.

[0032] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of the vehicle hybrid thermal management method provided in Embodiment 1 of the present invention;

[0034] Figure 2 This is a schematic diagram of the hybrid thermal management system provided in Embodiment 2 of the present invention;

[0035] Figure 3 For the present invention Figure 2 Schematic diagram of pulse signal feedback during normal operation of a medium-frequency variable pump;

[0036] Figure 4 For the present invention Figure 2 Schematic diagram of pulse signal feedback when a medium-frequency variable pump experiences a stall error;

[0037] Figure 5 For the present invention Figure 2 Schematic diagram of pulse signal feedback when a medium-frequency variable pump experiences a stall error;

[0038] Figure 6 For the present invention Figure 2 Schematic diagram of pulse signal feedback when a medium-frequency variable pump malfunctions due to idling.

[0039] Figure 7 For the present invention Figure 2 Schematic diagram of pulse signal feedback when a medium-frequency variable pump malfunctions due to idling.

[0040] Figure 8 For the present invention Figure 2 Schematic diagram of pulse signal feedback when a medium-frequency variable pump experiences an over-temperature error;

[0041] Figure 9 For the present invention Figure 2 Schematic diagram of pulse signal feedback when an overcurrent error occurs in a medium-frequency variable pump;

[0042] Figure 10 For the present invention Figure 2 A schematic diagram of pulse signal feedback when there is no PWM signal or input to the medium-frequency pump.

[0043] Explanation of key component symbols:

[0044] 10. Battery heat exchange circuit; 11. First heat exchanger; 12. Second heat exchanger; 13. Power battery; 14. Heating device; 20. Engine heat exchange circuit; 21. Engine; 22. Radiator; 23. Cabin heat source; 24. First three-way valve; 30. Air conditioning heat exchange circuit; 31. Compressor; 32. Cabin evaporator; 33. Second three-way valve; 40. Variable frequency pump.

[0045] The following detailed description, in conjunction with the accompanying drawings, will further illustrate the present invention. Detailed Implementation

[0046] To facilitate understanding of the present invention, a more complete description will be given below with reference to the accompanying drawings. Several embodiments of the invention are illustrated in the drawings. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

[0047] It should be noted that when a component is said to be "fixed to" another component, it can be directly on the other component or there may be an intervening component. When a component is said to be "connected to" another component, it can be directly connected to the other component or there may be an intervening component. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this document are for illustrative purposes only.

[0048] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0049] Example 1

[0050] Please see Figure 1The image shows a vehicle hybrid thermal management method according to the first embodiment of the present invention. This vehicle hybrid thermal management method is applied to a vehicle thermal circuit, which includes at least two heat exchange circuits that exchange heat with each other. Each heat exchange circuit is equipped with a variable frequency pump. The vehicle hybrid thermal management method specifically includes steps S10 to S50:

[0051] S10, construct the pre-controlled heat transfer intensity model and the feedback heat transfer intensity model;

[0052] S20: Obtain the heat load of the heat source and the measured temperature of the cooling medium in each heat exchange loop, and input the heat load of the heat source and the measured temperature of the cooling medium into the pre-controlled heat exchange intensity model to obtain the pre-controlled value of the heat exchange intensity.

[0053] In practical implementation, nanofluids can be used as the cooling medium in each heat exchange loop. During implementation, it was found that the nonlinearity of heat transfer intensity in the system's heat exchange loops is significant. For nonlinear calculations, appropriately reducing the calculation precision can improve the program's calculation speed. The lookup table method is the most commonly used method for quickly performing nonlinear calculations. A table is created based on the range and precision requirements of the independent variable. The calculation required for the lookup table method is simply to determine the table address based on the input value, and then obtain the corresponding value based on the address, thus requiring relatively little computation.

[0054] Specifically, in this implementation, the pre-controlled heat transfer intensity model contains a pre-defined pre-controlled heat transfer intensity value table. Optionally, the pre-controlled heat transfer intensity value table can be pre-drawn based on engineering experience. Different addresses in the specific pre-controlled heat transfer intensity value table correspond to different pre-controlled heat transfer intensity values. In this embodiment, the heat load of the heat source in each heat exchange loop and the corresponding measured temperature of the cooling medium are obtained as input values ​​for querying the pre-controlled heat transfer intensity value table. The heat load of the heat source directly determines the heat output per unit time of the heat source, while the temperature of the cooling medium determines the basic cooling capacity. The address of the pre-controlled heat transfer intensity value table is determined based on the two input values, and the corresponding pre-controlled heat transfer intensity value can be obtained from the address, denoted as p. pre .

[0055] S30, acquire the target temperature of the cooling medium in each heat exchange loop, and input the measured temperature of the cooling medium and the target temperature of the cooling medium into the feedback heat exchange intensity model to obtain the heat exchange intensity feedback value;

[0056] In practical implementation, the PI (Proportional-Integral) control principle is used in the feedback heat transfer intensity model to calculate the measured temperature and target temperature of the cooling medium. The PI control principle mainly uses proportional and integral algorithms to adjust the controlled value; it is widely used in control systems for variables such as temperature, pressure, flow rate, and velocity. The specific control process of the PI control principle is an existing control process and will not be elaborated here. Specifically, in this embodiment, the calculation expression for the heat transfer intensity feedback value through PI control is:

[0057] p fdb (t)=k p e(t)+k i ∫e(t)dt+u

[0058] In the formula, p fdb The calculated heat transfer intensity feedback value is given by k, where e(t) is the control error, which is the target temperature of the cooling medium minus the measured temperature of the cooling medium. p k is the proportional term correction coefficient in the PI control. i The integral term correction coefficient in the PI control is given by u, which is the basic control variable and is usually a set value; k is the coefficient of variation. p and k i The specific determination can be made after comprehensive calibration based on the sensitivity and stability of the heat exchange circuit.

[0059] S40, calculate the total heat exchange intensity value in each heat exchange loop according to the heat exchange intensity pre-control value and the heat exchange intensity feedback value, adjust the speed, pulsation amplitude and pulsation frequency of the variable frequency pump according to the total heat exchange intensity value, and adjust the heat transfer coefficient of the cooling medium in each heat exchange loop according to the pulsation amplitude and the pulsation frequency.

[0060] In practical implementation, the aforementioned heat exchange intensity pre-control value p in each heat exchange loop will be used. pre The total heat transfer intensity value p in each heat exchange loop is obtained by summing the heat transfer intensity feedback value and the total heat transfer intensity value p. oto The specific calculation formula is as follows:

[0061] p tot =p pre +p fdb

[0062] In the formula, p oto p represents the total heat transfer intensity. pre Pre-controlled value of heat transfer intensity, p fdb This is the feedback value for heat exchange intensity.

[0063] Based on the total heat transfer intensity value in different heat exchange loops, the speed, pulsation amplitude, and pulsation frequency of the variable frequency pump in the heat exchange loop are adjusted accordingly. The flow rate of the cooling medium in the heat exchange loop is adjusted by the speed of the variable frequency pump, and the Nusselt coefficient N of the cooling medium is adjusted by the pulsation amplitude and pulsation frequency of the variable frequency pump. u .

[0064] Specifically, the pulsating frequency refers to the number of periodic changes in velocity or pressure of a pulsating flow per unit time. For pulsating fluids in a pipe, the pulsating frequency determines the pulsating velocity and pulsating pressure. The pulsating velocity directly affects the changes in axial and radial velocity gradients, especially the radial velocity gradient near the wall and the rate of backflow. The pulsating amplitude mainly includes the amplitude of pulsating velocity and pulsating pressure. When the pulsating pressure amplitude reaches a certain level, it will cause reciprocating flow phenomena. The Nusselt number N... u The Nusselt number is a metric indicating the intensity of convective heat transfer, and also represents the ratio of the thermal resistance of the laminar sublayer to the convective heat transfer resistance. u The calculation expression is:

[0065]

[0066] In the formula, D is the geometric length of the heat transfer surface; λ is the thermal conductivity of the fluid; and h is the heat transfer coefficient of the fluid.

[0067] Experiments have shown that the Nusselt number N under pulsating flow u The value will vary depending on the pulsation frequency and amplitude. Therefore, by adjusting the pulsation amplitude and frequency of the variable frequency pump, the pulsation amplitude and frequency of the cooling medium can be changed, thus affecting the Nusselt number N of the pulsating fluid. u This, in turn, affects the heat transfer coefficient of the fluid.

[0068] S50, heat exchange is achieved according to the cooling medium in each heat exchange circuit to perform mixed thermal management of the whole vehicle;

[0069] In practice, different heat sources in different heat exchange loops may lead to variations in the heat load of the heat source, the measured temperature of the cooling medium, and the target temperature of the cooling medium, thus affecting the calculated total heat transfer intensity value p for different heat exchange loops. oto Different, specifically, in this embodiment, based on the total heat transfer intensity value p in different heat exchange loops. otoThe speed, pulsation amplitude, and pulsation frequency of the variable frequency pumps in each heat exchange circuit are adaptively adjusted to change the flow rate and heat dissipation coefficient of the cooling medium in each circuit accordingly. This ultimately enables rapid heat exchange between the cooling mediums in different heat exchange circuits, keeping the temperature of each component in each heat exchange circuit within a suitable range. Under the same heat dissipation effect, the power and volume of the pumps and cooling fans are effectively reduced. Specifically, in this embodiment, the cooling mediums in different heat exchange circuits can exchange heat through heat exchangers.

[0070] In summary, the vehicle hybrid thermal management method in the above embodiments of the present invention calculates the total heat transfer intensity value p for different heat exchange circuits based on the different heat source heat loads, measured temperatures of cooling media, and target temperatures of cooling media in each heat exchange circuit of the vehicle system. oto The difference lies in the total heat transfer intensity value p within different heat exchange loops. oto By adaptively adjusting the speed, pulsation amplitude, and pulsation frequency of the variable frequency pumps in each heat exchange loop, the flow rate and heat transfer coefficient of the cooling medium in each loop change accordingly. This ultimately enables rapid heat exchange between the cooling media in different heat exchange loops, keeping the temperature of each component in each heat exchange loop within a suitable range. Specifically, in this embodiment, the cooling media in different heat exchange loops can exchange heat through heat exchangers. The flow rate and heat transfer coefficient of the cooling media in each cooling loop can be changed according to heat dissipation needs. Under the same heat dissipation effect for the entire vehicle system, compared with the traditional method of increasing the speed of the cooling fan, the area of ​​the radiator, and the backup power of the variable frequency pump, this avoids wasting resources. The cooperation of multiple heat exchange loops can effectively improve the overall thermal management efficiency of the system and has practical application value.

[0071] Example 2

[0072] In another aspect, this invention also proposes a vehicle hybrid thermal management system, employing the vehicle hybrid thermal management method described in Embodiment 1. Please refer to [link / reference needed]. Figure 2 The image shows a vehicle hybrid thermal management system according to a second embodiment of the present invention. The system includes at least: a battery heat exchange circuit 10, an engine heat exchange circuit 20, and an air conditioning heat exchange circuit 30.

[0073] It should be noted that this embodiment is based on an HTCM (Hybrid Thermal Control Module), which has at least cabin system thermal management and powertrain system thermal management functions. The hybrid thermal management system operates under various typical conditions. When cabin system thermal management and powertrain system thermal management coexist, the HTCM prioritizes different operating modes to ensure the thermal management needs of both the passenger cabin and the powertrain system are met. For example, when the battery temperature exceeds a limit and the BMS (Battery Management System) issues a cooling or heating request, priority is given to ensuring the battery's cooling and heating needs. When the passenger cabin or battery requires cooling or heating, the HTCM sends a power request to the VCU (Vehicle Control Unit), and the HTCM provides feedback on the actual current power of the electric compressor.

[0074] Optionally, in this embodiment, a first heat exchanger 11 is provided between the battery heat exchange circuit 10 and the engine heat exchange circuit 20. The cooling medium in the battery heat exchange circuit 10 and the cooling medium in the engine heat exchange circuit 20 exchange heat in the first heat exchanger 11, and the heat generated by the engine raises the temperature of the cooling medium in the battery heat exchange circuit 10. A second heat exchanger 12 is provided between the battery heat exchange circuit 10 and the air conditioning heat exchange circuit 30. The cooling medium in the battery heat exchange circuit 10 and the cooling medium in the engine heat exchange circuit 20 exchange heat in the second heat exchanger 12, and the cooling medium in the battery heat exchange circuit 10 is cooled by the air conditioning. Each of the battery heat exchange circuit 10, the engine heat exchange circuit 20 and the air conditioning heat exchange circuit 30 is equipped with a variable frequency pump 40. The variable frequency pump adjusts the flow rate, pulsation amplitude and pulsation frequency of the cooling medium in each circuit to adjust the flow rate and heat transfer coefficient of the cooling medium according to the specific operating conditions, so as to achieve rapid heat transfer between the heat exchange circuits.

[0075] Specifically, the battery heat exchange circuit 10 also includes a power battery 13 and a heating device 14. The cooling medium in the battery heat exchange circuit 10 passes sequentially through the outlet end of the power battery 13, the heating device 14, the first heat exchanger 11, the second heat exchanger 12, the variable frequency pump 40, and returns to the inlet end of the power battery 13. The battery heat exchange circuit 10 is mainly used to keep the power battery working within a suitable temperature range. The heating device adopts electric heating to heat the cooling medium in the battery heat exchange circuit under low temperature conditions. The flow rate and heat transfer coefficient of the cooling medium in the battery heat exchange circuit 10 can be adjusted by the variable frequency pump 40 in the battery heat exchange circuit 10.

[0076] The engine heat exchange circuit 20 also includes an engine 21, a radiator 22, a variable frequency pump 40, and a cabin heat source 23. The engine heat exchange circuit 20 includes a first circuit and a second circuit. In the first circuit, the cooling medium sequentially passes through the engine 21 outlet, radiator 22, variable frequency pump 40, and cabin heat source 23 before returning to the engine inlet. In the first circuit, some of the heat generated by the engine can be used by the cabin through the cabin heat source 23 as needed. In the second circuit, the cooling medium sequentially passes through the engine 21 outlet, radiator 22, variable frequency pump 40, and first heat exchanger 11 before returning to the engine inlet. In the second circuit, some of the heat generated by the engine can be used by the power battery through the first heat exchanger 11 as needed, and some can be released into the air through the radiator 22 to prevent the engine from overheating. Specifically, by using the first three-way valve 24 after the variable frequency pump in the engine heat exchange circuit 20, a partially shared first circuit and second circuit are formed, thereby maximizing the utilization of the waste heat generated by the engine and improving the energy efficiency of the whole vehicle. The flow rate and heat transfer coefficient of the cooling medium in the engine heat exchange circuit 20 can be adjusted by the variable frequency pump 40 in the engine heat exchange circuit 20.

[0077] The air conditioning heat exchange circuit 30 also includes a compressor 31, a cabin evaporator 32, and a variable frequency pump 40. The air conditioning heat exchange circuit 30 includes a third circuit and a fourth circuit. The cooling medium in the third circuit passes sequentially through the outlet end of the compressor 31, the cabin evaporator 32, and returns to the inlet end of the compressor 31. The cooling medium in the air conditioning heat exchange circuit 30 absorbs heat from the cabin through the cabin evaporator 32 in the third circuit, thus cooling the cabin. The cooling medium in the fourth circuit passes sequentially through the outlet end of the compressor 31, the second heat exchanger 12, and the variable frequency pump 40 and returns to the inlet end of the compressor. The cooling medium in the air conditioning heat exchange circuit 30 absorbs heat from the battery heat exchange circuit 10 through the second heat exchanger 12 in the fourth circuit, thus cooling the power battery. Specifically, the air conditioning heat exchange circuit 30 is split at the outlet end using a second three-way valve 33 to form a partially shared third circuit and a fourth circuit. Optionally, the compression and condensation of the cooling medium in the compressor 31 allows the heat in the cooling medium to be carried away by the air; the flow rate and heat transfer coefficient of the cooling medium in the air conditioning heat exchange circuit 30 can be adjusted by the variable frequency pump 40 in the air conditioning heat exchange circuit 30.

[0078] The vehicle hybrid thermal management system provided in this embodiment of the invention has a similar implementation principle and technical effects to the aforementioned method embodiment. For the sake of brevity, any parts not mentioned in the system embodiment can be referred to the corresponding content in the aforementioned method embodiment.

[0079] Specifically, in this embodiment, the HTCM can continuously monitor the operating status of the variable frequency pump and send feedback signals to the VCU based on the operating status; specifically, the operating status of the variable frequency pump includes, but is not limited to, the following:

[0080] Normal operation:

[0081] like Figure 3 As shown, when the variable frequency pump is working normally, it continuously outputs a low-level signal.

[0082] Stall error:

[0083] like Figure 4 As shown, when a stall occurs, the variable frequency pump will automatically stop and restart after 5 seconds. After three consecutive failed restarts, the pump will not restart and will output a PWM (Pulse Width Modulation) signal with a 100% duty cycle. The pump will resume operation only after a power cycle (with the protection threshold adjusted to 255).

[0084] Overvoltage error:

[0085] like Figure 5 As shown, when the variable frequency pump detects a power supply voltage greater than 18.5V for 1 second, the pump will stop running and enter overvoltage protection mode, while simultaneously outputting a PWM signal with a 100% duty cycle. When the power supply voltage drops below 16V, the pump will automatically release the overvoltage protection and restart running within 1 second.

[0086] Idle spin error:

[0087] like Figure 6 As shown, the variable frequency pump controller determines that the pump is running idle for 2 minutes. After this period, the pump stops and requires a power cycle to resume operation. When idle operation is detected, a PWM signal with a frequency of 10Hz and a duty cycle of 40% is output (the protection threshold is adjusted to 250).

[0088] Undervoltage error:

[0089] like Figure 7 As shown, when the variable frequency pump detects a power supply voltage below 7V for 1 second, it will stop running and enter undervoltage protection mode, while simultaneously outputting a PWM signal with a 100% duty cycle. When the power supply voltage recovers to above 8.5V, the variable frequency pump will automatically release the undervoltage protection and then restart running within 1 second.

[0090] Over-temperature error:

[0091] like Figure 8 As shown, when the temperature of the variable frequency pump controller chip exceeds 150℃, the variable frequency pump will enter a shutdown protection state and simultaneously output a PWM signal with a 100% duty cycle. After an over-temperature error occurs, the variable frequency pump needs to be powered on again to run again (the protection threshold is adjusted to 255).

[0092] Overcurrent error:

[0093] like Figure 9 As shown, when the variable frequency pump is running, if the instantaneous current is too large, the variable frequency pump will immediately stop for protection. After 0.5 seconds, the error will be automatically cleared and the pump will restart. If the current is greater than a certain value and the duration exceeds 3 seconds, the variable frequency pump will stop running and output a PWM signal with a duty cycle of 100%. In this case, the overcurrent error will not be cleared automatically and will need to be cleared by restarting after power failure (the protection threshold is adjusted to 255).

[0094] When the variable frequency pump is running with no PWM input:

[0095] like Figure 10 As shown, if there is no PWM control signal input, or the PWM input duty cycle is 0%, or the PWM input duty cycle is 100%, or the PWM signal line is floating, the variable frequency pump will operate at maximum power (rated power) and the variable frequency pump fault signal output will have a 70% duty cycle fault signal; this fault will be automatically cleared when the PWM control signal input is normal.

[0096] It should be noted that the above implementation process is only to illustrate the feasibility of this application, but it does not mean that the sub-dashboard hover armrest of this application has only the above implementation process. On the contrary, as long as the sub-dashboard hover armrest of this application can be implemented, it can be included in the feasible implementation scheme of this application.

[0097] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0098] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

Claims

1. A vehicle hybrid thermal management method, applied to a vehicle thermal circuit, wherein the vehicle thermal circuit includes at least two heat exchange circuits, each of which is equipped with a variable frequency pump, characterized in that: The vehicle hybrid thermal management method includes: Construct a pre-controlled heat transfer intensity model and a feedback heat transfer intensity model; The heat load of the heat source and the measured temperature of the cooling medium in each heat exchange loop are obtained respectively. The heat load of the heat source and the measured temperature of the cooling medium are input into the pre-controlled heat exchange intensity model to obtain the pre-controlled value of the heat exchange intensity. The target temperature of the cooling medium in each heat exchange loop is obtained, and the measured temperature of the cooling medium and the target temperature of the cooling medium are input into the feedback heat transfer intensity model to obtain the heat transfer intensity feedback value. The total heat exchange intensity value in each heat exchange loop is calculated based on the heat exchange intensity pre-control value and the heat exchange intensity feedback value. The speed, pulsation amplitude and pulsation frequency of the variable frequency pump are adjusted based on the total heat exchange intensity value. The heat transfer coefficient of the cooling medium in each heat exchange loop is adjusted based on the pulsation amplitude and the pulsation frequency. Heat exchange is achieved using the cooling medium within each heat exchange circuit to perform mixed thermal management of the vehicle.

2. The vehicle hybrid thermal management method according to claim 1, characterized in that, The pre-controlled heat transfer intensity model includes a pre-controlled heat transfer intensity value table. The step of inputting the heat source heat load and the measured temperature of the cooling medium into the pre-controlled heat transfer intensity model to obtain the pre-controlled heat transfer intensity value specifically includes: querying the pre-controlled heat transfer intensity value table according to the heat source heat load and the measured temperature of the cooling medium to obtain the pre-controlled heat transfer intensity value.

3. The vehicle hybrid thermal management method according to claim 1, characterized in that, The step of inputting the measured temperature of the cooling medium and the target temperature of the cooling medium into the feedback heat transfer intensity model to obtain the heat transfer intensity feedback value specifically includes: using PI control to calculate the input measured temperature of the cooling medium and the target temperature of the cooling medium to obtain the heat transfer intensity feedback value.

4. The vehicle hybrid thermal management method according to claim 3, characterized in that, The calculation expression for the PI control is: P fdb (t)=k p e(t)+k i ∫e(t)dt+u In the formula, e(t) represents the control error, which is the target temperature of the cooling medium minus the measured temperature of the cooling medium, and k p k is the proportional term correction coefficient in the PI control. i U is the correction coefficient for the integral term in the PI control, and u is the basic control quantity.

5. The vehicle hybrid thermal management method according to claim 1, characterized in that, The step of adjusting the heat transfer coefficient of the cooling medium in each heat exchange circuit according to the pulsation amplitude and the pulsation frequency specifically includes: adjusting the Nusselt coefficient of the cooling medium according to the pulsation amplitude and the pulsation frequency, and adjusting the cooling coefficient of the cooling medium according to the Nusselt coefficient.

6. The vehicle hybrid thermal management method according to claim 5, characterized in that, The expression for calculating the Nusselt coefficient is as follows: In the formula, D is the geometric length of the heat transfer surface; λ is the thermal conductivity of the fluid; and h is the heat transfer coefficient of the cooling medium.

7. A vehicle hybrid thermal management system employing the vehicle hybrid thermal management method according to any one of claims 1-6, characterized in that, The hybrid thermal management system includes at least: a battery heat exchange circuit, an engine heat exchange circuit, and an air conditioning heat exchange circuit; A first heat exchanger is provided between the battery heat exchange circuit and the engine heat exchange circuit, and the cooling medium in the battery heat exchange circuit and the cooling medium in the engine heat exchange circuit exchange heat in the first heat exchanger. A second heat exchanger is provided between the battery heat exchange circuit and the air conditioning heat exchange circuit, and the cooling medium in the battery heat exchange circuit and the cooling medium in the engine heat exchange circuit exchange heat in the second heat exchanger.

8. The vehicle hybrid thermal management system according to claim 7, characterized in that, The battery heat exchange circuit also includes a power battery and a heating device. The cooling medium in the battery heat exchange circuit passes sequentially through the power battery outlet, the heating device, the first heat exchanger, the second heat exchanger, and the variable frequency pump back to the power battery inlet.

9. The vehicle hybrid thermal management system according to claim 7, characterized in that, The engine heat exchange circuit also includes an engine, a radiator, a variable frequency pump, and a cabin heat source, and the engine heat exchange circuit includes a first circuit and a second circuit; The cooling medium in the first circuit passes sequentially through the engine outlet, the radiator, the variable frequency pump, and the cabin heat source back to the engine inlet. The cooling medium in the second circuit passes sequentially through the engine outlet, the radiator, the variable frequency pump, and the first heat exchanger before returning to the engine inlet.

10. The vehicle hybrid thermal management system according to claim 7, characterized in that, The air conditioning heat exchange circuit also includes a compressor, a cabin evaporator, and a variable frequency pump. The air conditioning heat exchange circuit includes a third circuit and a fourth circuit. The cooling medium in the third circuit passes sequentially through the compressor outlet end and the cabin evaporator back to the compressor inlet end; The cooling medium in the fourth circuit passes sequentially through the compressor outlet, the second heat exchanger, and the variable frequency pump back to the compressor inlet.

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