Cooling circuit regulation method, system and readable storage medium based on pressure protection

Abstract

The present application discloses a cooling circuit regulation method, system, and readable storage medium based on pressure protection, which belongs to the field of thermal management of new energy vehicles. The method includes: obtaining the maximum allowable pressure value of the cooling pipeline by presetting the target flow of the cooling circuit; determining the maximum cooling allowable flow of the cooling circuit based on the maximum allowable pressure value; obtaining the cooling demand flow of each component to be cooled; determining the ideal output flow of the water pump that meets the cooling demand of each component to be cooled based on the cooling demand flow of multiple components to be cooled; determining the actual output flow of the water pump based on the maximum cooling allowable flow and the ideal output flow of the water pump. The present application not only takes into account the impact of temperature on the cooling circuit, but also takes into account pressure changes. It can make timely corrections to the flow rate or flow rate change rate of the water pump of the cooling circuit, solving the problem of pipeline rupture caused by excessive pressure in the cooling circuit.

Description

Technical Field

[0001] The present application relates to the field of thermal management of new energy vehicles, and specifically relates to a cooling circuit adjustment method, system and readable storage medium based on pressure protection. Background Art

[0002] New energy vehicles have high requirements for the sealing and stability of the liquid cooling system. Once the cooling system pipes rupture, fall off, or leak, the vehicle will be unable to apply high voltage, high-voltage components will short-circuit and cause components to burn, and the vehicle will directly release high voltage, insulation / short-circuit (internal pipes of high-voltage components rupture), and pipe rupture without cooling function. Components will quickly overheat and stop working. These faults may affect the normal use of the vehicle functions at the least and endanger driving safety at the worst.

[0003] Currently, when designing thermal management systems for new energy vehicles, the primary principle is to control the cooling system's water pump and fan based on a target temperature. When the circuit coolant temperature is too high, the system controls the fan and water pump to run at a higher speed. When the circuit coolant temperature is below the target temperature, the system controls the fan and water pump to run at medium or low speeds, or simply maintains the water pump at a constant speed. During the implementation of this application, the inventors discovered that the prior art has at least the following problems: It only considers adjusting the coolant target temperature, without considering the impact of changes in cooling circuit pressure due to changes in cooling flow on the cooling circuit's function. This single cooling control approach can lead to problems such as pipe rupture and coolant leakage due to excessive pressure in the cooling circuit. Summary of the Invention

[0004] The purpose of the embodiments of the present application is to provide a cooling circuit regulation method, system and readable storage medium based on pressure protection, which can solve the problem of cooling circuit rupture caused by excessive cooling circuit pressure during cooling regulation of the cooling system through a water pump.

[0005] In order to solve the above technical problems, this application is implemented as follows:

[0006] In a first aspect, an embodiment of the present application provides a cooling circuit regulation method based on pressure protection, the method comprising:

[0007] The maximum allowable pressure value of the cooling pipeline is obtained by presetting the target flow of the cooling circuit;

[0008] According to the maximum allowable pressure value, determine the maximum allowable cooling flow of the cooling circuit;

[0009] Obtain the cooling flow required for each component to be cooled;

[0010] determining an ideal output flow rate of a water pump that satisfies the cooling demand of each of the plurality of components to be cooled based on the cooling demand flow rates of the plurality of components to be cooled;

[0011] Determine the actual output flow of the water pump based on the maximum cooling allowable flow and the ideal output flow of the water pump.

[0012] Optionally, the step of obtaining the maximum allowable pressure value of the cooling pipeline by presetting the target flow of the cooling circuit specifically includes:

[0013] Based on the initial flow, multiple target flows are obtained according to the preset flow increment rules;

[0014] Controlling the cooling circuit to operate at multiple target flow rates respectively, and obtaining pressure values ​​of multiple cooling pipes corresponding to the multiple target flow rates;

[0015] Formulate a first calibration table based on the target flow rate and pressure value, wherein the pressure value is the maximum value of the pressure value at each point of the cooling pipeline;

[0016] Based on the first calibration table, a maximum allowable pressure value of the cooling pipe is determined.

[0017] Optionally, the step of determining the maximum allowable cooling flow rate of the cooling circuit according to the maximum allowable pressure value specifically includes:

[0018] Collect the real-time maximum pressure value of the cooling pipeline, wherein the real-time maximum pressure value is the maximum value of the real-time pressure values ​​of multiple points in the cooling pipeline;

[0019] If the real-time maximum pressure value is less than the maximum allowable pressure value, the target flow corresponding to the maximum allowable pressure value is set as the maximum cooling demand flow of the cooling circuit according to the first calibration table.

[0020] Optionally, the step of obtaining the required cooling flow of each component to be cooled specifically includes:

[0021] Based on the calibrated temperature of each component to be cooled and the change in the preset flow rate, the cooling flow rate corresponding to each calibrated temperature is determined. The cooling flow rate is the minimum flow rate required for the initial temperature of the component to be cooled to no longer rise and to have a downward trend.

[0022] Establishing a second calibration table according to the calibration temperatures of the plurality of components to be cooled and the plurality of cooling flow rates corresponding thereto;

[0023] Collect the real-time temperature of each component to be cooled;

[0024] Based on the second calibration table, the cooling flow corresponding to the real-time temperature is set as the cooling demand flow.

[0025] Optionally, the step of determining an ideal output flow rate of a water pump that meets the cooling demand of each of the multiple components to be cooled based on the cooling demand flow rates of the multiple components to be cooled specifically includes:

[0026] Determine the ideal output flow of the pump according to the following relationship:

[0027] S T =max{S T1 , S T2 , S T3 ,…,S Tn}

[0028] Among them, S T is the ideal output flow of the water pump, S Tn The cooling demand flow corresponding to the real-time temperature of each component to be cooled.

[0029] Optionally, the step of determining the actual output flow of the water pump according to the maximum cooling allowable flow and the ideal output flow of the water pump specifically includes:

[0030] Determine whether the ideal output flow of the water pump is greater than the maximum cooling allowable flow of the cooling circuit;

[0031] If so, the actual output flow of the pump is determined according to the following relationship:

[0032] S=min{S P0 , S T}

[0033] If not, determine the actual output flow of the pump according to the following relationship:

[0034] S=S T <S P0

[0035] Among them, S is the actual output flow of the pump, S P0 is the maximum cooling flow allowed by the cooling circuit, S T It is the ideal output flow of the water pump.

[0036] Optionally, the cooling circuit adjustment method based on pressure protection may further include:

[0037] Based on the initial flow rate change rate, target flow rate change rates of the plurality of cooling circuits are obtained according to a preset flow rate change rate increasing rule;

[0038] Controlling the cooling circuit to operate at a plurality of target flow rate change rates respectively, and obtaining transient pressure values ​​of a plurality of cooling pipes corresponding to the plurality of target flow rate change rates;

[0039] A third calibration table is formulated based on the target flow rate change rate and the transient pressure value, wherein the transient pressure value is the maximum value of the transient pressure value at each point in the cooling pipeline;

[0040] determining a maximum transient allowable pressure value of the cooling circuit based on a third calibration table;

[0041] Collect the instantaneous real-time maximum pressure value of the cooling pipe;

[0042] If the instantaneous real-time maximum pressure value is less than the maximum instantaneous allowable pressure value, the absolute value of the target flow rate change rate corresponding to the maximum instantaneous allowable pressure value is set as the maximum allowable flow rate change rate according to the third calibration table;

[0043] The absolute value of the actual output flow rate change rate of the control water pump shall not be greater than the maximum allowable flow rate change rate.

[0044] In a second aspect, an embodiment of the present application provides a cooling circuit regulation system based on pressure protection, the system comprising:

[0045] Signal acquisition and processing module: used to detect and collect data on temperature, pressure, flow rate and flow rate change rate, and transmit the data to the control decision module after processing;

[0046] Control decision module: used to receive the data from the signal acquisition and processing module, generate corresponding control instructions, and pass them to the control output module;

[0047] Control output module: used to receive the control instructions transmitted by the control decision module, and send PWM signals according to the control instructions to drive the processor to complete the corresponding control instructions for the water pump.

[0048] In a third aspect, an embodiment of the present application provides a computer device comprising a processor, a memory, and a program or instruction stored in the memory and executable on the processor, wherein the program or instruction, when executed by the processor, implements the steps of the method described in the first aspect.

[0049] In a fourth aspect, an embodiment of the present application provides a readable storage medium, on which a program or instruction is stored. When the program or instruction is executed by a processor, the steps of the method described in the first aspect are implemented.

[0050] In an embodiment of the present application, the pressure of the cooling circuit and the temperature of the components to be cooled in the cooling circuit are monitored in real time, thereby controlling the flow rate or flow rate change rate of the cooling circuit to adjust the pressure of the cooling circuit so that the pressure of the cooling circuit is within the maximum allowable pressure range that the cooling circuit can withstand; the maximum allowable pressure value of the cooling pipe is obtained by presetting the target flow rate of the cooling circuit, and this maximum allowable pressure value is the boundary value of the cooling circuit pressure, and the flow rate of the cooling circuit can be controlled according to the maximum allowable pressure value; according to the maximum allowable pressure value, the maximum cooling allowable flow rate of the cooling circuit is determined, and the actual output flow rate of the water pump is controlled based on this maximum cooling allowable flow rate; each component to be cooled is obtained The cooling flow rate of the components to be cooled is determined by monitoring the cooling flow rate of all components to be cooled in real time, thereby determining the ideal output flow rate of the water pump. Based on the cooling flow rates of multiple components to be cooled, the ideal output flow rate of the water pump that meets the cooling needs of each of the multiple components to be cooled is determined, and the actual output flow rate of the water pump is controlled based on this ideal output flow rate. The actual output flow rate of the water pump is determined based on the maximum cooling allowable flow rate and the ideal output flow rate of the water pump, and the output flow value of the water pump is controlled based on this actual output flow rate. The flow rate change rate is also adjusted so that the absolute value of the actual output flow rate change rate of the water pump is not greater than the maximum allowable flow rate change rate. Therefore, this adjustment method can effectively and timely control the water pump flow rate or flow rate change rate, thereby adjusting the pressure of the cooling circuit to ensure that it does not exceed the maximum allowable pressure value. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 is a flow chart of a cooling circuit adjustment method based on pressure protection provided by some embodiments of the present application;

[0052] Figure 2 is a schematic diagram of a cooling circuit provided by some embodiments of the present application;

[0053] Figure 3 is a communication principle diagram of a cooling control system provided by some embodiments of the present application;

[0054] Figure 4 is a flow chart of controlling flow rate change based on pressure provided by some embodiments of the present application;

[0055] Figure 5 This is a structural diagram of a cooling circuit regulation system based on pressure protection provided in some embodiments of the present application. DETAILED DESCRIPTION

[0056] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0057] The terms "first," "second," and the like in the specification and claims of this application are used to distinguish similar objects and are not used to describe a particular order or precedence. It should be understood that the terms used in this manner are interchangeable where appropriate so that the embodiments of this application can be implemented in an order other than those illustrated or described herein. In addition, the term "and / or" in the specification and claims refers to at least one of the connected objects, and the character " / " generally indicates that the objects associated with each other are in an "or" relationship.

[0058] The following, in conjunction with the accompanying drawings, describes in detail the cooling circuit regulation method, system and readable storage medium based on pressure protection provided by the embodiments of the present application through specific embodiments and their application scenarios.

[0059] In one possible embodiment, see Figure 1 , which is a flow chart of a cooling circuit regulation method based on pressure protection proposed in a possible embodiment of the present application, the proposed method includes:

[0060] S101: Obtaining a maximum allowable pressure value of the cooling pipeline by presetting a target flow rate of the cooling circuit;

[0061] S102: Determine the maximum cooling flow rate of the cooling circuit according to the maximum allowable pressure value;

[0062] S103: Obtaining the cooling flow required for each component to be cooled;

[0063] S104: determining an ideal output flow rate of a water pump that satisfies the cooling demand of each of the plurality of components to be cooled based on the cooling demand flows of the plurality of components to be cooled;

[0064] S105: Determine the actual output flow of the water pump according to the maximum cooling allowable flow and the ideal output flow of the water pump.

[0065] In this embodiment, the maximum allowable pressure value in step S101 can be obtained by experiments, simulations or optimization algorithms to obtain the correspondence between the target flow of the cooling circuit and the maximum allowable pressure value of the cooling pipe. The correspondence can be made into a first calibration table and stored in a lookup table of the vehicle control unit.

[0066] Optionally, step S101 specifically includes selecting a target vehicle, including selecting a thermal management system, a layout scheme, pipe material selection, coolant viscosity, etc. Pipe materials and coolant viscosity vary from vehicle to vehicle, and are selected based on actual conditions. Pressure gauges are placed at multiple points in the cooling pipeline, and flow meters are placed to measure the flow at the water pump output, and tests are conducted under different ambient temperature conditions. The test process can be based on an initial flow rate, and according to a preset flow rate increment rule, multiple target flow rates are obtained; the cooling circuit is controlled to operate at the multiple target flow rates, respectively, to obtain pressure values ​​of multiple cooling pipelines corresponding to the multiple target flow rates; a first calibration table is prepared based on the target flow rates and pressure values, wherein the pressure value is the maximum value of the pressure values ​​at each point in the cooling pipeline; and based on the first calibration table, the maximum allowable pressure value of the cooling pipeline is determined.

[0067] It should be noted that the traffic increase rule needs to be analyzed according to the specific actual situation to obtain a reasonable increment and obtain multiple target traffic.

[0068] It should be noted that this maximum allowable pressure value is the maximum pressure value that the system can withstand. In order to prevent the maximum pressure corresponding to the target flow from having a tendency and risk of coolant leakage, the maximum allowable pressure value must satisfy the relationship: P0=Pa-△P, where △P is the pressure redundancy value to ensure the safe operation of the system. The redundancy value must be determined according to the specific situation. Pa is the maximum pressure value corresponding to a certain flow rate, and P0 is the maximum allowable pressure value. This maximum allowable pressure value is the maximum pressure value that the system can withstand.

[0069] Table 1 First calibration table of target flow rate of cooling circuit and maximum allowable pressure value of cooling pipe

[0070]

[0071] In this embodiment, in step S102, the maximum cooling allowable flow rate of the cooling circuit is determined based on the maximum allowable pressure value. Specifically, the real-time maximum pressure value of the cooling pipeline is collected in real time by a pressure sensor, wherein the real-time maximum pressure value is the maximum value of the real-time pressure values ​​collected by pressure sensors arranged at multiple points in the cooling pipeline; if this real-time maximum pressure value meets the condition of being less than the maximum allowable pressure value, then the target flow rate corresponding to the maximum allowable pressure value is set as the maximum cooling demand flow rate of the cooling circuit according to the first calibration table, and the table lookup method can adopt the existing linear interpolation method.

[0072] In this example, see Figure 2 Cooling circuit schematic, Figure 3The cooling control system communication schematic diagram shows the cooling circuit, which includes cooling lines, a water pump, multiple components to be cooled, a low-temperature radiator (fan), an auxiliary water tank, temperature sensors, pressure sensors, and more. The components to be cooled include a DC inverter controller (DCDC / OBC two-in-one), a motor controller, and the motor itself. The system uses data collected by temperature and pressure sensors to control the coolant stored in the auxiliary water tank to circulate through the cooling pipes, passing through each component to be cooled. This coolant is removed through heat exchange, lowering the temperature. The low-temperature radiator (fan) then dissipates the heat to the outside environment. A greater flow rate removes more heat, while also increasing the pressure in the cooling lines. The cooling control system communication principle involves the cooling controller acquiring electrical signals from the pressure and temperature sensors to obtain temperature and pressure data. The cooling controller, high-voltage inverter controller, and motor controller are connected via the CAN bus. The cooling controller is integrated into the vehicle controller.

[0073] In this embodiment, step S103 can obtain the corresponding relationship between the temperature of multiple components to be cooled and the cooling required flow rate through experiments, simulations or optimization algorithms. The corresponding relationship can be made into a second calibration table and stored in the lookup table of the vehicle control unit.

[0074] Optionally, the cooling demand flow of each component to be cooled in step S103 can be obtained by determining the cooling flow corresponding to each calibrated temperature based on the calibrated temperature of each component to be cooled and the change in the preset flow, the cooling flow being the minimum flow required to ensure that the initial temperature of the component to be cooled no longer rises and has a downward trend, and the temperature of the component to be cooled falls back to its reasonable range; a second calibration table is established based on the calibrated temperatures of multiple components to be cooled and the multiple corresponding cooling flows; the real-time temperature of each component to be cooled in the cooling circuit is obtained through communication interaction between the cooler and the components to be cooled in the cooling circuit, the second calibration table is looked up based on this real-time temperature, and the flow corresponding to this real-time temperature is set as the cooling demand flow of the component to be cooled, wherein the table lookup method can adopt the existing linear interpolation method.

[0075] It should be noted that the preset flow rate change should be analyzed based on specific actual conditions and maintained within a reasonable range. The temperature range within which the component to be cooled can operate normally and maintain performance is defined as follows: for example, under normal operating conditions, the recommended motor controller temperature should not exceed 80°C, the motor body (stator) temperature should not exceed 135°C, and the motor controller IGBT junction temperature should not exceed 145°C. Maintaining component temperatures within a reasonable range improves performance and lifespan, minimizing the risk of failure. The reasonable temperature range varies for different components to be cooled and should be determined based on actual conditions.

[0076] It should be noted that the second calibration table includes calibration tables of multiple components to be cooled, such as a calibration table of the correspondence between the motor body calibration temperature and the cooling flow rate, a calibration table of the motor controller calibration temperature and the cooling flow rate, etc.

[0077] Table 2 Calibration table of motor body temperature and cooling flow in the second calibration table

[0078]

[0079] Table 3 Calibration table of motor controller temperature and cooling flow in the second calibration table

[0080]

[0081] Table 4 Calibration table of temperature and cooling flow of DC inverter controller (DCDC / OBC two-in-one) in the second calibration table

[0082]

[0083] From the above, the other components to be cooled S can be obtained by the same logic Tn Calibration table of temperature and cooling flow.

[0084] In this embodiment, the specific steps of determining the ideal output flow rate of the water pump that meets the cooling demand of each of the multiple components to be cooled based on the cooling demand flow rates of the multiple components to be cooled in step S104 are:

[0085] The ideal output flow of the water pump is calculated according to the following relationship:

[0086] S T =max{S T1 , S T2 , S T3 ,…,S Tn}

[0087] Among them, S T is the ideal output flow of the water pump, S Tn The maximum value among them is the ideal output flow rate of the water pump, which can ensure that the ideal output flow rate of the water pump can meet the cooling requirements of all components to be cooled.

[0088] In this embodiment, the specific steps of determining the actual output flow rate of the water pump according to the maximum cooling allowable flow rate and the ideal output flow rate of the water pump in step S105 are:

[0089] Determine whether the ideal output flow of the water pump is greater than the maximum cooling allowable flow of the cooling circuit;

[0090] If so, the actual output flow of the pump is determined according to the following relationship:

[0091] S=min{S P0 , S T}

[0092] If not, determine the actual output flow of the pump according to the following relationship:

[0093] S=S T <S P0

[0094] Among them, S is the actual output flow of the pump, S P0 is the maximum cooling flow allowed by the cooling circuit, S T It is the ideal output flow of the water pump.

[0095] It should be noted that if the ideal output flow rate of the water pump is greater than the maximum cooling allowable flow rate of the cooling circuit, it means that the pressure of the cooling circuit caused by this ideal output flow rate of the water pump will exceed the maximum cooling allowable pressure of the cooling circuit, causing the cooling pipe to burst, thereby making the components in the cooling circuit unable to function. The purpose of taking the maximum cooling allowable flow rate of the cooling circuit as the ideal output flow rate of the water pump is to ensure the safety of the cooling circuit and prevent excessive pressure in the cooling pipe.

[0096] It should be noted that if the ideal output flow of the water pump is less than the maximum cooling allowable flow of the cooling circuit, the actual output flow of the water pump is equal to the ideal output flow of the water pump and less than the maximum cooling allowable flow of the cooling circuit, ensuring that the pressure caused by the actual output flow of the water pump is no higher than the maximum cooling allowable pressure of the cooling circuit while allowing the components to be cooled to be fully cooled.

[0097] In summary, by real-time monitoring of the pressure of the cooling circuit and the temperature of the components to be cooled in the cooling circuit, the flow rate or flow rate change rate of the cooling circuit is controlled to adjust the pressure of the cooling circuit so that the pressure of the cooling circuit is within the maximum allowable pressure range that the cooling circuit can withstand; by presetting the target flow rate of the cooling circuit, the maximum allowable pressure value of the cooling pipe is obtained, and this maximum allowable pressure value is the boundary value of the cooling circuit pressure, and the flow rate of the cooling circuit can be controlled according to this maximum allowable pressure value; based on the maximum allowable pressure value, the maximum cooling allowable flow rate of the cooling circuit is determined, and the actual output flow rate of the water pump is controlled based on this maximum cooling allowable flow rate as one basis; the cooling demand flow rate of each component to be cooled is obtained, and the cooling demand flow rate of all components to be cooled is obtained by real-time monitoring of the temperature of the components to be cooled, so that the flow rate to be output by the water pump under ideal conditions can be obtained; based on the cooling demand flow rates of multiple components to be cooled, the ideal output flow rate of the water pump that meets the cooling demand of each of the multiple components to be cooled is determined, and the actual output flow rate of the water pump is controlled based on this ideal output flow rate as another basis; based on the maximum cooling allowable flow rate and the ideal output flow rate of the water pump, the actual output flow rate of the water pump is determined, and the output flow value of the water pump is controlled based on this actual output flow rate. Therefore, the regulation method can effectively and timely control the water pump flow rate and thus regulate the pressure of the cooling circuit so that it does not exceed the maximum allowable pressure value.

[0098] In one possible embodiment, see Figure 4 The cooling circuit regulation method based on pressure protection may further include the step of regulating the cooling circuit pressure by controlling the flow rate change rate: S401: based on the initial flow rate change rate, according to the preset flow rate change rate increasing rule, obtaining the target flow rate change rate of multiple cooling circuits; S402: controlling the cooling circuit to operate at multiple target flow rate change rates respectively, and obtaining the transient pressure values ​​of multiple cooling pipes corresponding to the multiple target flow rate change rates; S403: formulating a third calibration table according to the target flow rate change rate and the transient pressure value, wherein the transient pressure value is the maximum value of the transient pressure value of each point in the cooling pipe ; S404: Based on the third calibration table, determine the maximum transient allowable pressure value of the cooling circuit; S405: Collect the transient real-time maximum pressure value of the cooling pipe through the pressure sensor; S406: If the transient real-time maximum pressure value meets the condition of being less than the maximum transient allowable pressure value, then the absolute value of the target flow rate change rate corresponding to the maximum transient allowable pressure value is set as the maximum allowable flow rate change rate according to the third calibration table, and the table lookup method can adopt the existing linear interpolation method; S407: Under all working conditions, the absolute value of the actual output flow rate change rate of the water pump is controlled to be no greater than the maximum allowable flow rate change rate.

[0099] It should be noted that the increasing rule of the flow rate change rate in S401 needs to be analyzed according to the specific actual situation to obtain a reasonable increasing amount and obtain multiple target flow rates.

[0100] Optionally, the maximum allowable flow rate change rate in S406 can be obtained by experiments, simulations or optimization algorithms to obtain the correspondence between the target flow rate of the cooling circuit and the maximum transient allowable pressure value of the cooling pipe. The third calibration table made from the correspondence can be stored in the lookup table of the vehicle control unit.

[0101] Table 5 The third calibration table of the target flow rate change rate of the cooling circuit and the transient pressure value of the cooling pipe

[0102]

[0103] Optionally, in S407, the actual output flow rate change rate of the water pump is controlled to be no greater than the maximum allowable flow rate change rate under all working conditions. Specifically, when identifying the need to stop the water pump, the on-off state of the water pump relay, the duty cycle value of the water pump, etc. can be used for judgment; when identifying the need to power off the entire vehicle, the vehicle start switch state can be used for judgment. Currently, the cooling water pumps on the entire vehicle are mostly controlled by voltage duty cycle. For example, the duty cycle and flow characteristics of a certain water pump are as follows: when PWM is 0, the water pump stops; when PWM is in the (0, 7%) range, it runs at the maximum speed; when PWM is When the PWM duty cycle is in the range of (7%, 12%), the pump stops; when the PWM duty cycle is in the range of (12%, 17%), the pump runs at the minimum speed; when the PWM duty cycle is in the range of (17%, 93%), the pump speed runs linearly (the duty cycle is positively correlated with the pump speed); when the PWM duty cycle is in the range of (93%, 100%), the pump runs at the maximum speed. The operating speed of the pump is linearly proportional to the pump flow rate (the faster the pump speed, the greater the output water flow rate). Therefore, the rate of change of the pump flow rate can be controlled by changing the duty cycle sent to the pump.

[0104] The above-mentioned step of regulating the cooling circuit pressure by controlling the flow change rate can avoid the problem of damage to the cooling circuit due to water hammer effect caused by excessive transient pressure caused by water pump flow instantaneous change too fast or shutdown by controlling the flow change rate.

[0105] In one possible embodiment, see Figure 5 , shown is a schematic diagram of the structure of a cooling circuit regulation system based on pressure protection, which includes:

[0106] Signal acquisition and processing module 501: used to detect and acquire data on temperature, pressure, flow rate and flow rate change rate, and transmit the processed data to the control decision module;

[0107] Control decision module 502: used to receive the data from the signal acquisition and processing module, generate corresponding control instructions, and pass them to the control output module;

[0108] The control output module 503 is used to receive the control instructions transmitted by the control decision module, and send PWM signals according to the control instructions to control the flow change or flow change rate of the water pump, and control the speed of the low-temperature radiator (fan).

[0109] Optionally, an embodiment of the present application also provides a computer device, including a processor, a memory, and a program or instruction stored in the memory and executable on the processor. When the program or instruction is executed by the processor, the various processes of the above-mentioned embodiment of the cooling circuit regulation method based on pressure protection are implemented, and the same technical effect can be achieved. To avoid repetition, it will not be repeated here.

[0110] An embodiment of the present application also provides a readable storage medium, on which a program or instruction is stored. When the program or instruction is executed by a processor, the various processes of the above-mentioned cooling circuit adjustment method embodiment based on pressure protection are implemented, and the same technical effect can be achieved. To avoid repetition, it will not be repeated here.

[0111] The processor is the processor in the electronic device described in the above embodiment. The readable storage medium includes a computer-readable storage medium, such as a computer read-only memory (ROM), random access memory (RAM), a magnetic disk, or an optical disk.

[0112] It should be noted that, in this article, the terms "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the statement "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device comprising the element. In addition, it should be noted that the scope of the methods and devices in the embodiments of the present application is not limited to performing functions in the order shown or discussed, and may also include performing functions in a substantially simultaneous manner or in the opposite order according to the functions involved. For example, the described method may be performed in an order different from that described, and various steps may also be added, omitted, or combined. In addition, the features described with reference to certain examples may be combined in other examples.

[0113] Through the description of the above embodiments, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus the necessary general hardware platform. Of course, they can also be implemented by hardware, but in many cases the former is a more preferred embodiment. Based on this understanding, the technical solution of this application, or the part that contributes to the existing technology, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk), and includes a number of instructions for enabling a terminal (which can be a mobile phone, computer, server, air conditioner, or network device, etc.) to execute the methods described in each embodiment of this application.

[0114] The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of this application, ordinary technicians in this field can also make many forms without departing from the purpose of this application and the scope of protection of the claims, all of which are within the protection of this application.

Claims

1. A cooling circuit adjustment method based on pressure protection, applied to new energy vehicles, wherein the cooling circuit includes a cooling pipe, a water pump and a plurality of components to be cooled, characterized in that: The method comprises: Obtaining a maximum allowable pressure value of the cooling pipeline by presetting a target flow rate of the cooling circuit; determining a maximum cooling allowable flow rate of the cooling circuit according to the maximum allowable pressure value; Obtaining the cooling flow rate required for each component to be cooled; Determining an ideal output flow rate of a water pump that satisfies the cooling demand of each of the plurality of components to be cooled based on the cooling demand flow rates of the plurality of components to be cooled, specifically includes: The ideal output flow of the water pump is determined according to the following relationship: S T =max{S T1 ,S T2 ,S T3 ,…,S Tn } Among them, S T is the ideal output flow of the water pump, S Tn The cooling demand flow corresponding to the real-time temperature of each component to be cooled; Determining the actual output flow of the water pump based on the maximum cooling allowable flow rate and the ideal output flow rate of the water pump, specifically including: Determining whether the ideal output flow of the water pump is greater than the maximum cooling allowable flow of the cooling circuit; If so, the actual output flow of the water pump is determined according to the following relationship: S=min{S P0 ,S T } If not, the actual output flow of the water pump is determined according to the following relationship: S=S T <S P0 Wherein, S is the actual output flow of the water pump, S P0 is the maximum cooling flow allowed by the cooling circuit, S T is the ideal output flow of the water pump.

2. The cooling circuit adjustment method based on pressure protection according to claim 1, characterized in that: The step of obtaining the maximum allowable pressure value of the cooling pipeline by presetting the target flow of the cooling circuit specifically includes: Based on the initial flow rate, a plurality of target flow rates are obtained according to a preset flow rate increasing rule; controlling the cooling circuit to operate at a plurality of target flow rates respectively, and obtaining pressure values ​​of a plurality of cooling pipes corresponding to the plurality of target flow rates; formulating a first calibration table according to the target flow rate and the pressure value, wherein the pressure value is the maximum value of the pressure values ​​at each point of the cooling pipeline; Based on the first calibration table, a maximum allowable pressure value of the cooling pipe is determined.

3. The cooling circuit adjustment method based on pressure protection according to claim 2, characterized in that: The step of determining the maximum cooling allowable flow rate of the cooling circuit according to the maximum allowable pressure value specifically includes: collecting a real-time maximum pressure value of the cooling pipeline, wherein the real-time maximum pressure value is a maximum value of real-time pressure values ​​of multiple points in the cooling pipeline; If the real-time maximum pressure value is less than the maximum allowable pressure value, the target flow corresponding to the maximum allowable pressure value is set as the maximum cooling demand flow of the cooling circuit according to the first calibration table.

4. The cooling circuit adjustment method based on pressure protection according to claim 1, characterized in that: The step of obtaining the cooling flow rate required for each component to be cooled specifically includes: Based on the calibrated temperature of each component to be cooled and the change in the preset flow rate, determining the cooling flow rate corresponding to each calibrated temperature, the cooling flow rate being the minimum flow rate required for the initial temperature of the component to be cooled to no longer rise and to have a downward trend; Establishing a second calibration table according to the calibration temperatures of the plurality of components to be cooled and the plurality of cooling flow rates corresponding thereto; Collecting the real-time temperature of each component to be cooled; Based on the second calibration table, the cooling flow corresponding to the real-time temperature is set as the cooling demand flow.

5. The cooling circuit adjustment method based on pressure protection according to claim 1, characterized in that: The method further comprises: Based on the initial flow rate change rate, according to a preset flow rate change rate increasing rule, a target flow rate change rate of the plurality of cooling circuits is obtained; controlling the cooling circuit to operate at a plurality of target flow rate change rates, respectively, and obtaining transient pressure values ​​of a plurality of cooling pipes corresponding to the plurality of target flow rate change rates; formulating a third calibration table according to the target flow rate change rate and the transient pressure value, wherein the transient pressure value is the maximum value of the transient pressure values ​​at each point of the cooling pipeline; determining a maximum transient allowable pressure value of the cooling circuit based on the third calibration table; Collecting the instantaneous real-time maximum pressure value of the cooling pipe; If the instantaneous real-time maximum pressure value is less than the maximum instantaneous allowable pressure value, then setting the absolute value of the target flow rate change rate corresponding to the maximum instantaneous allowable pressure value as the maximum allowable flow rate change rate according to the third calibration table; The absolute value of the actual output flow rate change rate of the water pump is controlled to be no greater than the maximum allowable flow rate change rate.

6. A system used in the cooling circuit regulation method based on pressure protection according to any one of claims 1 to 5, characterized in that: The system comprises: Signal acquisition and processing module: used to detect and collect data on temperature, pressure, flow rate and flow rate change rate, and transmit the data to the control decision module after processing; Control decision module: used to receive the data from the signal acquisition and processing module, generate corresponding control instructions, and pass them to the control output module; Control output module: used to receive the control instructions transmitted by the control decision module, and send PWM signals according to the control instructions to drive the processor to complete the corresponding control instructions.

7. A computer device, characterized in that: The computer device includes a memory, a processor, and a processing program stored in the memory and executable on the processor. When the processing program is executed by the processor, the cooling circuit regulation method based on pressure protection according to any one of claims 1 to 5 is implemented.

8. A readable storage medium, characterized in that: The readable storage medium stores a program or instruction, and when the program or instruction is executed by the processor, the steps of the cooling circuit regulation method based on pressure protection according to any one of claims 1 to 5 are implemented.

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