Cooling structure of intercooler of hybrid electric vehicle and control method of cooling structure

Abstract

The invention discloses a cooling structure of an intercooler of a hybrid electric vehicle and a control method of the cooling structure. A low-temperature radiator water outlet pipe is connected with a low-temperature radiator and an electronic water pump, an outlet of the electronic water pump is connected with a first connector of an electromagnetic three-way valve through an electronic water pump water outlet pipe, and a second connector of the electromagnetic three-way valve is connected with the intercooler through an intercooler water inlet pipe; according to the system and the method, the cooling performance of the intercooler can be accurately and dynamically controlled on the basis of not increasing the complexity and the arrangement space of the system. The control mode is particularly suitable for changeable weather conditions, and particularly in a high-humidity environment, the risk that water vapor is converted into condensate water at the rear portion of the intercooler can be effectively managed and reduced. According to the scheme, the problem that the engine is abnormal due to condensate water is remarkably solved, and therefore the reliability of the engine and the driving safety of the whole vehicle are improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of automobiles, and in particular relates to a cooling structure of an intercooler of a hybrid vehicle and a control method thereof. Background Art

[0002] In the process of implementing the present invention, the inventors found that the prior art has at least the following problems:

[0003] New energy hybrid vehicles with integrated intercoolers in the engine have multiple cooling system circuits, mainly including high-temperature engine cooling circuit, auxiliary heating circuit, battery cooling circuit, drive motor cooling circuit, circuit equipment cooling circuit and intercooler cooling circuit. Due to the limited space in the front cabin, the layout becomes extremely complicated. In order to reduce complexity and reduce vehicle cost, cooling circuits with similar water temperature requirements should be integrated as much as possible.

[0004] The integrated system integrates the battery cooling circuit, drive motor cooling circuit, circuit equipment cooling circuit and intercooler cooling circuit into a circuit driven by a single water pump through series and parallel connections. Since the circuit is equipped with only one water pump, a throttle valve is required to distribute the flow of each circuit. This practice may cause the intercooler cooling circuit to be overcooled under certain specific operating conditions. In a high humidity environment, water vapor in the fresh air and exhaust gas in the EGR (exhaust gas recirculation) system will be converted into condensed water after being cooled by the intercooler. If the condensed water is brought into the cylinder during transient acceleration of the vehicle, it will cause engine failure.

[0005] CN220009451U-Front end cooling module of hybrid vehicle and hybrid vehicle, discloses a front end cooling module of hybrid vehicle and hybrid vehicle. The front end cooling module includes an intermediate radiator, a first radiator, a second radiator, a third radiator and a fourth radiator. The first radiator and the second radiator are arranged on the windward side of the intermediate radiator, and the first radiator and the second radiator are arranged in the same row. The above technical problem cannot be solved either. Summary of the invention

[0006] The technical problem to be solved by the present invention is to provide a cooling structure and a control method for a hybrid vehicle intercooler, which can dynamically control the cooling performance of the intercooler without increasing the system complexity and layout space, and solve the problem that water vapor in the exhaust gas in the fresh air and EGR (exhaust gas recirculation) system is converted into condensed water in the intercooler under high humidity conditions.

[0007] In order to solve the above technical problems, the technical solution adopted by the present invention is: a cooling structure of a hybrid vehicle intercooler,

[0008] The low-temperature radiator water outlet pipe connects the low-temperature radiator and the electronic water pump, the outlet of the electronic water pump is connected to the first interface of the electromagnetic three-way valve through the electronic water pump water outlet pipe, the second interface of the electromagnetic three-way valve is connected to the intercooler through the intercooler water inlet pipe, and the intercooler water outlet pipe is connected to the low-temperature radiator return pipe.

[0009] The third interface of the electromagnetic three-way valve leads to other water branches.

[0010] The electronic water pump is fixed to the engine via a bracket.

[0011] In the initial state, the first, second and third interfaces of the electromagnetic three-way valve are all in a fully open state; when the intercooler cooling control strategy is activated, the system only adjusts the opening ratio of the second interface of the electromagnetic three-way valve, while the first and third interfaces remain in a fully open state.

[0012] The control method of the cooling structure of the hybrid vehicle intercooler comprises the following steps:

[0013] 1) Determine the target values ​​of the pressure after turbocharging and the gas temperature after intercooling;

[0014] 2) Determine the maximum relative humidity of the environment under common operating conditions of the vehicle model;

[0015] 3) Locking triggers the maximum ambient temperature of the intercooler condensate;

[0016] 4) Determine the control strategy for the three-way proportional solenoid valve.

[0017] In the above step 1), for hybrid vehicles, the engine is operated close to the optimal efficiency point; based on the engine's optimal efficiency point operating conditions, the pressure value after the turbocharger is measured to be 1.6 bar, and the intake air temperature after the intercooler is 42°C; the boost pressure value and the gas temperature value after the intercooler are initially locked in.

[0018] In the above step 2), an environmental chamber is established, and the intercooler performance is adjusted to ensure that the boost pressure is 1.6 bar, the air temperature after intercooling is 42°C, and the ambient relative humidity is 90%. The above three parameter targets are locked, the ambient temperature is adjusted, and the lowest ambient temperature of the condensed water after intercooling is tested.

[0019] In the above step 3), the maximum temperature of the condensed water after intercooling is tested in an environmental chamber under the same conditions; when the ambient temperature exceeds a certain critical value, the maximum cooling capacity of the intercooler is no longer sufficient to reduce the gas temperature after intercooling to below the dew point; at this time, the maximum ambient temperature that triggers the condensed water can be preliminarily locked as the critical value.

[0020] In the above step 4), the adjustment temperature range and adjustment frequency of the solenoid valve should be determined according to the accuracy and durability of the solenoid valve.

[0021] One of the above technical solutions has the following advantages or beneficial effects: it can dynamically control the cooling performance of the intercooler without increasing the system complexity and layout space, and solves the problem of water vapor in the exhaust gas in the fresh air and EGR (exhaust gas recirculation) system being converted into condensed water in the intercooler under high humidity environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 A schematic structural diagram of a cooling structure of a hybrid vehicle intercooler provided in an embodiment of the present invention;

[0023] Figure 2 for Figure 1 Schematic diagram of the cooling structure of the hybrid vehicle intercooler;

[0024] Figure 3 for Figure 1 The three-way solenoid valve angle flow diagram of the cooling structure of the hybrid vehicle intercooler;

[0025] The markings in the above figures are: 1. Engine, 2. Water inlet pipe, 3. Intercooler, 4. Water outlet pipe, 5. Solenoid three-way valve, 6. Low-temperature radiator return pipe, 7. Water branch, 8. Electronic water pump outlet pipe, 9. Electronic water pump, 10. Low-temperature radiator outlet pipe. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] Embodiment 1

[0028] See also Figures 1 to 3A cooling structure of an intercooler 3 of a hybrid vehicle, wherein a low-temperature radiator water outlet pipe 10 connects the low-temperature radiator and an electronic water pump, the outlet of the electronic water pump is connected to a first interface of an electromagnetic three-way valve 5 through an electronic water pump water outlet pipe 8, the second interface of the electromagnetic three-way valve 5 is connected to the intercooler 3 through an intercooler 3 water inlet pipe 2, and the intercooler 3 water outlet pipe is connected to a low-temperature radiator water return pipe 6, and finally returns to the low-temperature radiator. This path constitutes a cooling circuit of the intercooler 3. The electronic water pump is fixed to the engine 1 through a bracket. It is possible to achieve accurate and dynamic control of the cooling performance of the intercooler 3 without increasing the complexity of the system and the layout space. This control method is particularly suitable for variable climatic conditions, especially in high humidity environments, and can effectively manage and reduce the risk of water vapor being converted into condensed water at the rear of the intercooler 3. This solution significantly reduces the abnormal problems of the engine 1 caused by condensed water, thereby improving the reliability of the engine 1 and the driving safety of the whole vehicle.

[0029] The third interface of the electromagnetic three-way valve 5 leads to other water branch 7, which will not be elaborated here.

[0030] In the initial state, ports V1, V2 and V3 of the electromagnetic three-way valve 5 are all in a fully open state (the angle of the three-way electromagnetic valve is 66.7%). When the intercooler 3 temperature reduction control strategy is activated, the system will only adjust the opening ratio of port V2 of the electromagnetic three-way valve 5, while ports V1 and V3 remain in a fully open state.

[0031] The original intercooler 3 branch ordinary three-way valve is changed to an adjustable proportional electromagnetic three-way valve 5 (such as Figure 1 ), port V1 is the water inlet of the solenoid valve, port V2 is the water inlet of the cooling branch of the intercooler 3, and port V3 is the water inlet of the cooling circuit of the drive motor and the cooling circuit of the circuit equipment. Ports V1 and V3 are always connected, and port V2 is dynamically adjusted according to the needs of the intercooler 3 branches.

[0032] It is possible to achieve accurate and dynamic control of the cooling performance of the intercooler 3 without increasing the complexity of the system and the layout space. This control method is particularly suitable for changing climate conditions, especially in high humidity environments, and can effectively manage and reduce the risk of water vapor converting into condensed water at the rear of the intercooler 3. This solution significantly reduces the abnormal problems of the engine 1 caused by condensed water, thereby improving the reliability of the engine 1 and the driving safety of the entire vehicle.

[0033] Embodiment 2

[0034] A control method for the cooling structure of a hybrid vehicle intercooler, wherein a low-temperature radiator outlet pipe 1010 connects the low-temperature radiator and the electronic water pump 9, and the electronic water pump 9 is fixed to the engine 1 through a bracket. The outlet of the electronic water pump 9 is connected to the V1 port of the electromagnetic three-way valve 5 through the electronic water pump outlet pipe 88. The V2 port of the electromagnetic three-way valve 5 is connected to the intercooler 3 through the intercooler water inlet pipe 2, and the intercooler outlet pipe 4 is connected to the low-temperature radiator return pipe 6, and finally returns to the low-temperature radiator. This path constitutes the cooling circuit of the intercooler. The V3 port of the electromagnetic three-way valve 5 leads to other water branches 77, which will not be expanded in detail here.

[0035] In the initial state, ports V1, V2 and V3 of the electromagnetic three-way valve are all in full-open state (the angle of the three-way electromagnetic valve is 66.7%). When the intercooler cooling control strategy is activated, the system will only adjust the opening ratio of port V2 of the electromagnetic three-way valve, while ports V1 and V3 remain in full-open state.

[0036] Three-way solenoid valve control method:

[0037] The first step is to determine the target values ​​of the pressure after turbocharging and the gas temperature after intercooling. For hybrid models, the engine can work as close to the best efficiency point as possible. According to the engine's best efficiency point operating conditions, the pressure value after turbocharging is measured to be 1.6 bar, and the intake temperature after intercooling is 42°C. This preliminarily locks the target values ​​of the boost pressure value and the gas temperature value after intercooling.

[0038] The second step is to determine the maximum relative humidity of the environment under the common working conditions of this model. Taking China as an example, the relative humidity in different regions of China varies greatly. Generally, the relative humidity in coastal areas is higher, up to 90%. When the relative humidity is the same, the higher the temperature, the higher the water vapor content. It is necessary to establish an environmental chamber, adjust the performance of the intercooler, ensure the boost pressure is 1.6 bar, the air temperature after intercooling is 42°C, and the relative humidity of the environment is 90%. Lock the above three parameter targets, adjust the ambient temperature, and test the lowest ambient temperature of condensed water after intercooling. Assuming that the final result is measured at a temperature of -4°C, condensed water begins to appear after intercooling. At this time, the minimum ambient temperature that triggers the condensation of the intercooler can be initially locked as -4°C.

[0039] The third step is to lock the maximum ambient temperature that triggers the condensation of the intercooler. In an environmental chamber with the same conditions, test the maximum temperature of the condensed water after intercooling. Although the higher the temperature, the higher the ambient water vapor content, and the easier it is to form condensed water, the cooling performance of the intercooler will decrease with the increase in ambient temperature. When the ambient temperature exceeds a certain critical value, such as 35°C, the maximum cooling capacity of the intercooler is not enough to reduce the gas temperature after intercooling to below the dew point. Therefore, the maximum ambient temperature that triggers the condensation of water can be initially locked as 35°C.

[0040] The fourth step is to determine the control strategy of the three-way proportional solenoid valve. First, the accuracy of the solenoid valve must be determined. If the accuracy of the solenoid valve can only be controlled to 2%, then the angle adjustment amount of the solenoid valve in the control strategy cannot be less than 2%. Then, according to Figure 2 The angle flow diagram of the three-way proportional solenoid valve is used to formulate a preliminary control strategy, as shown in Table 1.

[0041] Table 1

[0042]

[0043] According to the preliminary strategy, the actual vehicle test confirmed that the adjustment frequency of the three-way proportional solenoid valve was too frequent. The adjustment frequency of the three-way valve in the HEV hybrid mode was 7 times / km under comprehensive road conditions. According to the mileage of 100,000 kilometers, the durability performance of the solenoid valve should be ≥ 700,000 times, which exceeds the durability requirement of the solenoid valve. Therefore, it is necessary to simplify and optimize the parameters in Table 1. The final optimization results are shown in Table 2.

[0044] Table 2

[0045]

[0046] In the actual vehicle test, no condensed water appeared after the intercooler in the comprehensive road conditions under the HEV hybrid mode. The adjustment frequency of the three-way valve is 3.2 times / km. According to the mileage of 100,000 km, the durability of the solenoid valve is about 320,000 times, which meets the durability requirements.

[0047] Step 5. Combining the above four steps, the three-way solenoid valve control strategy and activation conditions are finally locked as shown in Table 3.

[0048] Table 3

[0049]

[0050] Intercooler temperature control strategy:

[0051] The target temperature after the intercooler is 42°C.

[0052] 1) When the actual temperature after cooling is ≥49°C, the opening ratio of the three-way valve proportional valve is 66.7%, the opening ratio of the V1 port of the electromagnetic three-way valve is 100.00%, the opening ratio of the V2 port is 100.00%; the opening ratio of the V3 port is 100.00%;

[0053] 2) When the actual temperature after cooling is 48°C, the opening ratio of the three-way valve proportional valve is 70.4%, the opening ratio of the V1 port of the electromagnetic three-way valve is 100.00%, the opening ratio of the V2 port is 75.50%%; the opening ratio of the V3 port is 100.00%;

[0054] 3) When the actual temperature after cooling is 46°C, the opening ratio of the three-way valve proportional valve is 75.9%, the opening ratio of the V1 port of the electromagnetic three-way valve is 100.00%, the opening ratio of the V2 port is 38.02%; the opening ratio of the V3 port is 100.00%;

[0055] 4) When the actual temperature after cooling is 44°C, the opening ratio of the three-way valve proportional valve is 81.5%, the opening ratio of the V1 port of the electromagnetic three-way valve is 100.00%, the opening ratio of the V2 port is 8.32%; the opening ratio of the V3 port is 100.00%;

[0056] 5) When the actual temperature after cooling is 42°C, the opening ratio of the three-way valve proportional valve is 85.2%, the opening ratio of the V1 port of the electromagnetic three-way valve is 100.00%, the opening ratio of the V2 port is 1.54%; the opening ratio of the V3 port is 100.00%;

[0057] 6) When the actual temperature after cooling is ≤40°C, the opening ratio of the three-way valve proportional valve is 87.0%, the opening ratio of the V1 port of the electromagnetic three-way valve is 100.00%, the opening ratio of the V2 port is 0.00%; the opening ratio of the V3 port is 100.00%.

[0058] This hybrid vehicle intercooler cooling solution, through carefully designed control logic and technical applications, can achieve precise and dynamic control of intercooler cooling performance without increasing system complexity and layout space. This control method is particularly suitable for changing climate conditions, especially in high humidity environments, and can effectively manage and reduce the risk of water vapor converting into condensed water at the rear of the intercooler. This solution significantly reduces engine abnormalities caused by condensed water, thereby improving engine reliability and vehicle driving safety. In addition, the implementation of this solution does not require large-scale changes to the existing vehicle structure, providing automakers with a cost-effective solution without sacrificing vehicle performance and space efficiency.

[0059] The above solution can achieve accurate and dynamic control of the intercooler cooling performance without increasing the system complexity and layout space. This control method is particularly suitable for changing climate conditions, especially in high humidity environments, and can effectively manage and reduce the risk of water vapor turning into condensed water at the rear of the intercooler. This solution significantly reduces engine abnormalities caused by condensed water, thereby improving engine reliability and vehicle driving safety.

[0060] In the description of the present invention, it is necessary to understand that the terms "coaxial", "bottom", "one end", "top", "middle", "the other end", "upper", "one side", "top", "inside", "front", "center", "both ends" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0061] In the present invention, unless otherwise clearly stipulated and limited, the terms such as "installation", "setting", "connection", "fixation" and "screw-on" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be the internal connection of two elements or the interaction relationship between two elements. Unless otherwise clearly defined, ordinary technicians in this field can understand the specific meanings of the above terms in the present invention according to the specific circumstances.

[0062] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A cooling structure for a hybrid vehicle intercooler, characterized in that: The low-temperature radiator water outlet pipe connects the low-temperature radiator and the electronic water pump, the outlet of the electronic water pump is connected to the first interface of the electromagnetic three-way valve through the electronic water pump water outlet pipe, the second interface of the electromagnetic three-way valve is connected to the intercooler through the intercooler water inlet pipe, and the intercooler water outlet pipe is connected to the low-temperature radiator return pipe.

2. The cooling structure of the hybrid vehicle intercooler according to claim 1, characterized in that: The third interface of the electromagnetic three-way valve leads to other water branches.

3. The cooling structure of the hybrid vehicle intercooler according to claim 2, characterized in that: The electronic water pump is fixed to the engine via a bracket.

4. The cooling structure of the hybrid vehicle intercooler according to claim 3, characterized in that: In the initial state, the first, second and third interfaces of the electromagnetic three-way valve are all in a fully open state; when the intercooler cooling control strategy is activated, the system only adjusts the opening ratio of the second interface of the electromagnetic three-way valve, while the first and third interfaces remain in a fully open state.

5. The control method for the cooling structure of the hybrid vehicle intercooler according to claim 4, characterized in that: The steps include: 1) Determine the target values ​​of the pressure after turbocharging and the gas temperature after intercooling; 2) Determine the maximum relative humidity of the environment under common operating conditions of the vehicle model; 3) Locking triggers the maximum ambient temperature of the intercooler condensate; 4) Determine the control strategy of the three-way proportional solenoid valve.

6. The cooling structure and control method of the hybrid vehicle intercooler according to claim 5, characterized in that: In the above step 1), for hybrid vehicles, the engine is operated close to the optimal efficiency point; based on the engine's optimal efficiency point operating conditions, the pressure value after the turbocharger is measured to be 1.6 bar, and the intake air temperature after the intercooler is 42°C; the boost pressure value and the gas temperature value after the intercooler are initially locked in.

7. The control method of the cooling structure of the hybrid vehicle intercooler according to claim 6, characterized in that: In the above step 2), an environmental chamber is established, and the intercooler performance is adjusted to ensure that the boost pressure is 1.6 bar, the air temperature after intercooling is 42°C, and the ambient relative humidity is 90%. The above three parameter targets are locked, the ambient temperature is adjusted, and the lowest ambient temperature of the condensed water after intercooling is tested.

8. The control method for the cooling structure of the hybrid vehicle intercooler according to claim 7, characterized in that: In the above step 3), the maximum temperature of the condensed water after intercooling is tested in an environmental chamber under the same conditions; when the ambient temperature exceeds a certain critical value, the maximum cooling capacity of the intercooler is not enough to reduce the temperature of the gas after intercooling to below the dew point; At this point, the maximum ambient temperature that triggers condensation can be preliminarily locked as the critical value.

9. The control method for the cooling structure of the hybrid vehicle intercooler according to claim 8, characterized in that: In the above step 4), the adjustment temperature range and adjustment frequency of the solenoid valve should be determined according to the accuracy and durability of the solenoid valve.

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