Cooling method and cooling system for hybrid electric vehicle and hybrid electric vehicle

Abstract

The present application discloses a cooling method, cooling system and hybrid vehicle for a hybrid vehicle. The scheme is provided with a coupled radiator and a fluid on-off device. By obtaining first temperature information of a first cooling circuit and second temperature information of a second cooling circuit, and comparing the first temperature information with a first temperature threshold and the second temperature information with a second temperature threshold, the first temperature threshold is less than the second temperature threshold. When the first temperature information is lower than the first temperature threshold and the second temperature information is higher than the second temperature threshold, the fluid on-off device is controlled to conduct the flow path between the first fluid channel and the first component to be cooled and the first radiator, and the flow path between the second fluid channel and the second component to be cooled and the second radiator. The coolant of the first cooling circuit is pre-cooled to the coolant of the second cooling circuit, which can improve the cooling effect of the second cooling circuit, thereby improving the heat dissipation capacity of the entire cooling system.

Description

Technical Field

[0001] The present application relates to the technical field of vehicle thermal management, and in particular to a cooling method and cooling system for a hybrid electric vehicle and a hybrid electric vehicle. Background Art

[0002] Compared with traditional fuel vehicles, hybrid vehicles have added cooling requirements for the three-electric system in addition to the original cooling requirements. The heat load increases significantly, posing a huge challenge to the cooling system.

[0003] Currently, hybrid vehicle cooling systems consist of multiple, isolated cooling circuits, each dissipating heat independently for each subsystem. To maximize the cooling needs of each subsystem, the radiator in each cooling circuit is designed for maximum heat dissipation. This requires larger radiators and places greater demands on the hybrid vehicle's cabin space. Furthermore, isolated cooling circuits cannot fully utilize the cooling system's heat dissipation capacity. Summary of the Invention

[0004] In order to solve the above problems, the present application provides a cooling method, a cooling system and a hybrid vehicle for a hybrid vehicle.

[0005] The present application discloses a cooling method for a hybrid electric vehicle, wherein the hybrid electric vehicle includes a first cooling circuit and a second cooling circuit, wherein the first cooling circuit includes a first temperature detection device, a first fluid on-off device, a first radiator connected in sequence, a plurality of first heat dissipation components, a first connecting pipe connected in parallel, and a coupled radiator, wherein the coupled radiator has a first fluid channel and a second fluid channel, wherein the first fluid on-off device is disposed at one end of the first connecting pipe and the first fluid channel, and wherein the second cooling circuit includes a second temperature detection device, a second fluid on-off device, a second radiator connected in sequence, a plurality of second heat dissipation components, a second connecting pipe connected in parallel, and the coupled radiator, wherein the second fluid on-off device is disposed at one end of the second connecting pipe and the second fluid channel. The cooling method includes:

[0006] Acquire first temperature information detected by the first temperature detection device and second temperature information detected by the second temperature detection device;

[0007] comparing the first temperature information with a first temperature threshold and the second temperature information with a second temperature threshold, the first temperature threshold being smaller than the second temperature threshold;

[0008] When the first temperature information is lower than the first temperature threshold and the second temperature information is higher than the second temperature threshold, the first fluid on-off device is controlled to open the flow path between the first fluid channel and the first component to be cooled and the first radiator, and the second fluid on-off device is controlled to open the flow path between the second fluid channel and the second component to be cooled and the second radiator.

[0009] The above technical solutions provided by the embodiments of the present application include at least the following beneficial effects:

[0010] The above-mentioned technical solution provided by the present application is to set a coupling radiator, a first fluid on-off device, and a second fluid on-off device in the cooling system. The first fluid channel and the second fluid channel of the coupling radiator are respectively connected to the first cooling circuit and the second cooling circuit, and are connected in parallel with the first connecting pipe and the second connecting pipe. The first fluid on-off device is set at one end of the first connecting pipe and the first fluid channel, and the second fluid on-off device is set at one end of the second connecting pipe and the second fluid channel. By obtaining the first temperature information detected by the first temperature detection device and the second temperature information detected by the second temperature detection device, and comparing the size of the first temperature information with the first temperature threshold and the size of the second temperature information with the second temperature threshold, and the first temperature threshold is less than the second temperature threshold, Second temperature threshold: When the first temperature information is lower than the first temperature threshold and the second temperature information is higher than the second temperature threshold, the first cooling circuit has sufficient cooling capacity, while the second cooling circuit has insufficient cooling capacity. The first fluid on-off device is controlled to open the flow path between the first fluid channel and the first component to be cooled and the first radiator, and the second fluid on-off device is controlled to open the flow path between the second fluid channel and the second component to be cooled and the second radiator. At this time, the coolant in the first cooling circuit passes through the first fluid channel, and the coolant in the second cooling circuit passes through the second fluid channel. The coolant in the first cooling circuit is pre-cooled by the coolant in the second cooling circuit, which can improve the cooling effect of the second cooling circuit and thus improve the heat dissipation capacity of the entire cooling system. In addition, the present application has low cabin space requirements for hybrid vehicles.

[0011] In an exemplary embodiment, the cooling method further comprises:

[0012] When the second temperature information is lower than the second temperature threshold, controlling the first fluid on-off device to cut off the flow path between the first fluid channel and the first component to be cooled and the first radiator, and to open the flow path between the first connecting pipe and the first component to be cooled and the first radiator; and / or,

[0013] The second fluid on-off device is controlled to cut off the flow path between the second fluid channel and the second component to be cooled and the second radiator, and to open the flow path between the second connecting pipeline and the second component to be cooled and the second radiator.

[0014] The second cooling circuit serves as a high-temperature cooling circuit. When the cooling capacity of the second cooling circuit is sufficient, it is no longer necessary to use the coolant of the first cooling circuit for pre-cooling. The first fluid on-off device is controlled to cut off the flow path between the first fluid channel and the first component to be cooled and the first radiator, and the second fluid on-off device is controlled to cut off the flow path between the second fluid channel and the second component to be cooled and the second radiator, which can reduce the flow resistance of the coolant and improve the cooling efficiency.

[0015] In an exemplary embodiment, the first temperature detection device includes multiple first temperature sensors, each of which is arranged at the liquid inlet end or the liquid outlet end of the first component to be heat dissipated, and the first temperature information is the highest temperature among all temperature information detected by the multiple first temperature sensors; the second temperature detection device includes multiple second temperature sensors, each of which is arranged at the liquid inlet end or the liquid outlet end of the second component to be heat dissipated, and the second temperature information is the highest temperature among all temperature information detected by the multiple second temperature sensors.

[0016] Thereby, the first temperature information and the second temperature information can accurately represent the cooling conditions of the first cooling circuit and the second cooling circuit, while simplifying the subsequent temperature comparison procedure.

[0017] In an exemplary embodiment, the heat dissipation capacity of the first radiator is equal to the maximum heat dissipation demand of the several first components to be cooled, and the heat dissipation capacity of the second radiator is equal to the product of the difference between the maximum total heat dissipation demand of the several first components to be cooled and the several second components to be cooled and the maximum heat dissipation demand of the several first components to be cooled, and a preset safety factor.

[0018] Since the heat dissipation requirements of each subsystem do not reach their maximum at the same time under normal operating conditions, this method can save the space and cost required for the entire cooling system while meeting the heat dissipation requirements of each subsystem as much as possible.

[0019] In an exemplary embodiment, the coupled radiator includes a third fluid channel for circulating cooling air, an air inlet end of the third fluid channel is connected to an air inlet channel of the hybrid vehicle, and an air outlet end of the third fluid channel is connected to an air exhaust channel of the hybrid vehicle. The cooling method further includes:

[0020] When the first temperature information is higher than the first temperature threshold and the second temperature information is lower than the second temperature threshold, the first fluid on-off device is controlled to open the flow path between the first fluid channel and the first component to be cooled and the first radiator, and the second fluid on-off device is controlled to cut off the flow path between the second fluid channel and the second component to be cooled and the second radiator.

[0021] In this way, the coolant in the first cooling circuit and the coolant in the second cooling circuit can be cooled by the cooling air in the third fluid channel.

[0022] In an exemplary embodiment, the third fluid channel is provided between the first fluid channel and the second fluid channel, and the cooling method further comprises:

[0023] When the first temperature information is higher than the first temperature threshold and the second temperature information is higher than the second temperature threshold, the first fluid on-off device is controlled to open the flow path between the first fluid channel and the first component to be cooled and the first radiator, and the second fluid on-off device is controlled to open the flow path between the second fluid channel and the second component to be cooled and the second radiator.

[0024] In this way, the coolant in the first cooling circuit and the coolant in the second cooling circuit can be cooled by the cooling air in the third fluid channel.

[0025] In an exemplary embodiment, the first temperature threshold is less than or equal to the safe tolerance temperature of the plurality of first components to dissipate heat, and the second temperature threshold is less than or equal to the safe tolerance temperature of the plurality of second components to dissipate heat.

[0026] By determining whether the cooling capacity of the first cooling circuit and the second cooling circuit is insufficient or excessive based on the relationship between the coolant temperature of the first cooling circuit and the second cooling circuit and the safe tolerance temperature of the component to be dissipated, the cooling capacity of the first cooling circuit and the second cooling circuit can be accurately determined.

[0027] The present application also discloses a cooling system for a hybrid vehicle, which includes a first cooling circuit, a second cooling circuit and a control device, wherein the first cooling circuit includes a first temperature detection device, a first fluid on-off device, a first radiator connected in sequence, several first components to be cooled, a first connecting pipe in parallel and a coupling radiator, the coupling radiator has a first fluid channel and a second fluid channel, and the first fluid on-off device is arranged at one end of the first connecting pipe and the first fluid channel; the second cooling circuit includes a second temperature detection device, a second fluid on-off device, a second radiator connected in sequence, several second components to be cooled, a second connecting pipe in parallel and the coupling radiator, and the second fluid on-off device is arranged at one end of the second connecting pipe and the second fluid channel; the control device is electrically connected to the first temperature detection device, the second temperature detection device, the first fluid on-off device and the second fluid on-off device, and is configured to perform the cooling method as described above.

[0028] The above technical solutions provided by the embodiments of the present application include at least the following beneficial effects:

[0029] The above-mentioned technical solution provided by the present application is to set a coupling radiator, a first fluid on-off device, and a second fluid on-off device in the cooling system. The first fluid channel and the second fluid channel of the coupling radiator are respectively connected to the first cooling circuit and the second cooling circuit, and are connected in parallel with the first connecting pipe and the second connecting pipe. The first fluid on-off device is set at one end of the first connecting pipe and the first fluid channel, and the second fluid on-off device is set at one end of the second connecting pipe and the second fluid channel. By obtaining the first temperature information detected by the first temperature detection device and the second temperature information detected by the second temperature detection device, and comparing the size of the first temperature information with the first temperature threshold and the size of the second temperature information with the second temperature threshold, and the first temperature threshold is less than the second temperature threshold, Second temperature threshold: When the first temperature information is lower than the first temperature threshold and the second temperature information is higher than the second temperature threshold, the first cooling circuit has sufficient cooling capacity, while the second cooling circuit has insufficient cooling capacity. The first fluid on-off device is controlled to open the flow path between the first fluid channel and the first component to be cooled and the first radiator, and the second fluid on-off device is controlled to open the flow path between the second fluid channel and the second component to be cooled and the second radiator. At this time, the coolant in the first cooling circuit passes through the first fluid channel, and the coolant in the second cooling circuit passes through the second fluid channel. The coolant in the first cooling circuit is pre-cooled by the coolant in the second cooling circuit, which can improve the cooling effect of the second cooling circuit and thus improve the heat dissipation capacity of the entire cooling system. In addition, the present application has low cabin space requirements for hybrid vehicles.

[0030] In an exemplary embodiment, the first fluid on-off device is an electrically controlled three-way valve, the liquid inlet end of the first fluid on-off device is connected to the first component to be cooled, the first liquid outlet end of the first fluid on-off device is connected to the first connecting pipeline, the second liquid outlet end of the first fluid on-off device is connected to the first fluid channel, and the first connecting pipeline and the first fluid channel are connected to the first radiator via a first three-way pipe; and / or, the second fluid on-off device is an electrically controlled three-way valve, the liquid inlet end of the second fluid on-off device is connected to the second component to be cooled, the first liquid outlet end of the second fluid on-off device is connected to the second connecting pipeline, the second liquid outlet end of the second fluid on-off device is connected to the second fluid channel, and the second connecting pipeline and the second fluid channel are connected to the second radiator via a second three-way pipe.

[0031] The first fluid on-off device utilizes an electrically controlled three-way valve, which is low in cost and simplifies the control procedures for opening or closing the flow path between the first fluid channel and the first component to be cooled and the first radiator, and the flow path between the first connecting pipeline and the first component to be cooled and the first radiator. The second fluid on-off device utilizes an electrically controlled three-way valve, which is low in cost and simplifies the control procedures for opening or closing the flow path between the second fluid channel and the second component to be cooled and the second radiator, and the flow path between the second connecting pipeline and the second component to be cooled and the second radiator.

[0032] The present application also discloses a hybrid vehicle, which includes a vehicle body and a cooling system. The cooling system is arranged on the vehicle body and is as described above.

[0033] It should be understood that the foregoing general description and the following detailed description are merely illustrative and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0035] Figure 1 A schematic diagram showing a cooling system of a prior art hybrid vehicle is shown;

[0036] Figure 2 A flow chart showing a cooling method for a hybrid vehicle provided in the first embodiment of the present application is shown;

[0037] Figure 3 A flow chart showing a cooling method for a hybrid vehicle provided in the second embodiment of the present application is shown;

[0038] Figure 4 The figure shows the architecture of the cooling system of the hybrid vehicle provided in the first embodiment of the present application;

[0039] Figure 5 A block diagram showing part of the components of the cooling system provided in Example 1 of the present application is shown;

[0040] Figure 6 The figure shows the architecture of the cooling system of the hybrid vehicle provided in the second embodiment of the present application;

[0041] Figure 7 The following is an architecture diagram of a cooling system for a hybrid vehicle provided in the third embodiment of the present application;

[0042] Figure 8 A schematic diagram of the composition of a hybrid vehicle according to an embodiment of the present application is shown.

[0043] The following are the descriptions of the reference numerals:

[0044] 111. First temperature detection device; 112. First fluid switching device; 113. First radiator; 114. First pump body; LQ_1 / LQ_N, first component to be cooled; 115. First connecting pipeline; 116. First three-way pipe; 121. Second temperature detection device; 122. Second fluid switching device; 123. Second radiator; 124. Second pump body; HQ_1 / HQ_N, second component to be cooled; 125. Second connecting pipeline; 126. Second three-way pipe; 131. Cooling fan; 141. Control device; 151. Coupled radiator; 163. Third radiator; 164. Third pump body; MQ_1 / MQ_N, third component to be cooled; 801. Vehicle body; 802. Cooling system; 803. Air inlet channel; 804. Air exhaust channel; 805. Accommodation space. DETAILED DESCRIPTION

[0045] Although the present application can be easily embodied in different forms of embodiments, only some of the specific embodiments are shown in the drawings and will be described in detail in this specification. It should be understood that this description should be regarded as an exemplary illustration of the principles of the application and is not intended to limit the application to what is described herein.

[0046] In the description of the present application, it should be understood that the terms "front", "rear", etc. 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 application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", and "third" may explicitly or implicitly include one or more features. In the description of the present application, "several" means one or more, unless otherwise clearly and specifically defined, and "multiple" means two or more, unless otherwise clearly and specifically defined.

[0047] Furthermore, the terms "disposed," "equipped with," and "connected" should be interpreted broadly. For example, they can refer to fixed connections, removable connections, or integral structures; mechanical connections or point connections; direct connections, indirect connections through an intermediary, or internal connections between two devices, elements, or components. Those skilled in the art will understand the specific meanings of these terms in this application based on the specific circumstances.

[0048] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, these example embodiments are provided so that the description of this application will be thorough and complete and will fully convey the concepts of the example embodiments to those skilled in the art.

[0049] like Figure 1 As shown, the cooling system of an existing hybrid vehicle includes two isolated cooling circuits, one of which is a low-temperature cooling circuit for cooling the power battery, electronic control system, and motor (such as LQ_1, ..., LQ_N), and the other is a high-temperature cooling circuit for cooling the engine (such as HQ_1, ..., HQ_N).

[0050] To meet the cooling needs of each HEV subsystem, the radiators in each cooling circuit are currently designed for maximum cooling capacity, resulting in larger radiators and the use of high-power fans. This leaves little room for larger radiators in the HEV's engine compartment, making larger radiators impractical. Furthermore, the use of high-power fans significantly increases costs and negatively impacts noise and vehicle power management. Furthermore, under normal operating conditions, the cooling needs of each subsystem do not reach their maximum simultaneously. Furthermore, since each radiator cools the coolant through airflow, which in turn affects the wind flow field, cooling is affected. Consequently, some radiators often have insufficient cooling capacity while others have insufficient. This prevents the cooling system from fully utilizing its cooling capacity.

[0051] In response to the above problems, the present application provides a cooling method for a hybrid vehicle, a cooling system using the cooling method, and a hybrid vehicle having the cooling system. A coupling heat exchanger is arranged between different cooling circuits to achieve heat transfer between the coolants of different cooling circuits, so that the cooling circuit with excess cooling capacity can compensate for the cooling circuit with insufficient cooling capacity, thereby improving the cooling effect of the cooling circuit with insufficient cooling capacity, realizing coupled heat dissipation of each subsystem, and then through the fluid on-off device and pipeline setting, the heat dissipation of each subsystem is precisely controlled to give full play to the heat dissipation capacity of the cooling system.

[0052] The present application sets up a coupling radiator, a first fluid on-off device, and a second fluid on-off device in the cooling system. The first fluid channel and the second fluid channel of the coupling radiator are respectively connected to the first cooling circuit and the second cooling circuit, and are connected in parallel with the first connecting pipe and the second connecting pipe. The first fluid on-off device is set at one end of the first connecting pipe and the first fluid channel, and the second fluid on-off device is set at one end of the second connecting pipe and the second fluid channel. The first cooling circuit is used as a low-temperature cooling circuit and a first temperature detection device is set. The second cooling circuit is used as a high-temperature cooling circuit and a second temperature detection device is set. By obtaining first temperature information detected by a first temperature detection device and second temperature information detected by a second temperature detection device, and comparing the first temperature information with a first temperature threshold and the second temperature information with a second temperature threshold, and when the first temperature threshold is less than the second temperature threshold, it is determined that the cooling capacity of the first cooling circuit is sufficient and the cooling capacity of the second cooling circuit is insufficient. The first fluid switching device is controlled to open the flow path between the first fluid channel and the first component to be cooled and the first radiator, and the second fluid switching device is controlled to open the flow path between the second fluid channel and the second component to be cooled and the second radiator. At this time, the coolant in the first cooling circuit passes through the first fluid channel, and the coolant in the second cooling circuit passes through the second fluid channel. The coolant in the second cooling circuit is pre-cooled by the coolant in the first cooling circuit, thereby improving the cooling effect of the second cooling circuit and thereby improving the heat dissipation capacity of the entire cooling system. In addition, the present application has low cabin space requirements for hybrid vehicles.

[0053] First, the cooling method for the hybrid vehicle provided by the present application is described in detail below in conjunction with specific implementation methods.

[0054] Figure 2 The flowchart of the cooling method of the hybrid vehicle provided in the first embodiment of the present application is shown. The cooling method is applicable to the cooling system provided in the present application and can be executed by the control device of the hybrid vehicle, such as Figure 2 As shown, the cooling method includes at least the following steps S210 to S230, which are described in detail as follows:

[0055] In step S210, first temperature information detected by the first temperature detection device and second temperature information detected by the second temperature detection device are acquired.

[0056] In one embodiment, there are multiple first components to dissipate heat. Accordingly, the first temperature detection device includes multiple first temperature sensors, each of which is disposed at the liquid inlet or liquid outlet of a first component to dissipate heat. The first temperature information is the highest temperature among all the temperature information detected by the multiple first temperature sensors. By providing multiple first temperature sensors and using the highest temperature among all the temperature information detected by the multiple first temperature sensors as the first temperature information, the cooling condition of the first cooling circuit can be accurately characterized, while simplifying the temperature comparison procedure in the subsequent step S220.

[0057] Of course, the first temperature information is not limited to the highest temperature among all the temperature information detected by multiple first temperature sensors. For example, in some embodiments, only one first temperature sensor is set, and the first temperature information is the temperature information detected by the first temperature sensor. For another example, the average value of all the temperature information detected by multiple first temperature sensors is used as the first temperature information.

[0058] In one embodiment, there are multiple second components to dissipate heat. Accordingly, the second temperature detection device includes multiple second temperature sensors, each of which is positioned at the liquid inlet or liquid outlet of a second component to dissipate heat. The second temperature information is the highest temperature among all the temperature information detected by the multiple second temperature sensors. By providing multiple second temperature sensors and using the highest temperature among all the temperature information detected by the multiple second temperature sensors as the second temperature information, the cooling condition of the second cooling circuit can be accurately characterized, while simplifying the temperature comparison procedure in the subsequent step S220.

[0059] Of course, the second temperature information is not limited to the highest temperature among all the temperature information detected by multiple second temperature sensors. For example, in some embodiments, only one second temperature sensor is set, and the second temperature information is the temperature information detected by the second temperature sensor. For another example, the average value of all the temperature information detected by multiple second temperature sensors is used as the second temperature information.

[0060] In step S220, the first temperature information is compared with the first temperature threshold and the second temperature information is compared with the second temperature threshold. When the first temperature information is lower than the first temperature threshold and the second temperature information is higher than the second temperature threshold, it is considered that the cooling capacity of the first cooling circuit is sufficient, but the cooling capacity of the second cooling circuit is insufficient, and the process goes to step S230a. When the second temperature information is lower than the second temperature threshold, it is considered that the cooling capacity of the second cooling circuit is sufficient, and the process goes to step S230b.

[0061] The first temperature threshold is lower than the second temperature threshold. The first temperature threshold is lower than or equal to the safe tolerance temperature of each first component to be cooled, and the second temperature threshold is lower than or equal to the safe tolerance temperature of each second component to be cooled. That is, when the first temperature information is lower than the safe tolerance temperature of each first component to be cooled, and the second temperature information is higher than the safe tolerance temperature of each second component to be cooled, the process proceeds to step S230a. When the second temperature information is lower than the safe tolerance temperature of each second component to be cooled, the process proceeds to step S230b.

[0062] By determining whether the cooling capacity of the first cooling circuit and the second cooling circuit is insufficient or excessive based on the relationship between the coolant temperature of the first cooling circuit and the second cooling circuit and the safe tolerance temperature of the component to be dissipated, the cooling capacity of the first cooling circuit and the second cooling circuit can be accurately determined.

[0063] In step S230a, the first fluid on-off device is controlled to open the flow path between the first fluid channel and the first component to be cooled and the first radiator, and the second fluid on-off device is controlled to open the flow path between the second fluid channel and the second component to be cooled and the second radiator.

[0064] At this point, the coolant in the first cooling circuit passes through the first fluid channel, and the coolant in the second cooling circuit passes through the second fluid channel. The coolant in the first cooling circuit pre-cools the coolant in the second cooling circuit. The coolant in the second cooling circuit then passes through the second radiator, improving the cooling efficiency of the second cooling circuit and keeping the second temperature information below the second temperature threshold. In other words, the first cooling circuit's excess cooling capacity compensates for the second cooling circuit's insufficient cooling capacity, achieving coupled heat dissipation across the subsystems and fully utilizing the cooling capacity of the cooling system.

[0065] It should be noted that in step S230a, when controlling the first fluid on-off device to open the flow path between the first fluid channel and the first component to be cooled and the first radiator, the first fluid on-off device can be selectively controlled to simultaneously open the flow path between the first connecting pipeline and the first component to be cooled and the first radiator, that is, part of the cooling liquid after passing through the first component to be cooled flows to the first radiator through the first fluid channel, and part of the cooling liquid flows directly to the first radiator through the first connecting pipeline; or, the first fluid on-off device can be controlled to cut off the flow path between the first connecting pipeline and the first component to be cooled and the first radiator, that is, all the cooling liquid after passing through the first component to be cooled flows to the first radiator through the first fluid channel.

[0066] Similarly, in step S230a, when controlling the second fluid on-off device to open the flow path between the second fluid channel and the second component to be cooled and the second radiator, the second fluid on-off device can be selectively controlled to simultaneously open the flow path between the second connecting pipeline and the second component to be cooled and the second radiator, that is, part of the cooling liquid after passing through the second component to be cooled flows to the second radiator through the second fluid channel, and part of the cooling liquid directly flows to the second radiator through the second connecting pipeline; or, the second fluid on-off device can be controlled to cut off the flow path between the second connecting pipeline and the second component to be cooled and the second radiator, that is, all the cooling liquid after passing through the second component to be cooled flows to the second radiator through the second fluid channel.

[0067] In step S230b, the first fluid on-off device is controlled to cut off the flow path between the first fluid channel and the first component to be cooled and the first radiator, and to open the flow path between the first connecting pipeline and the first component to be cooled and the first radiator; and the second fluid on-off device is controlled to cut off the flow path between the second fluid channel and the second component to be cooled and the second radiator, and to open the flow path between the second connecting pipeline and the second component to be cooled and the second radiator.

[0068] The second cooling circuit serves as a high-temperature cooling circuit. When the cooling capacity of the second cooling circuit is sufficient, it is no longer necessary to use the coolant of the first cooling circuit for pre-cooling. The first fluid on-off device is controlled to cut off the flow path between the first fluid channel and the first component to be cooled and the first radiator, and the second fluid on-off device is controlled to cut off the flow path between the second fluid channel and the second component to be cooled and the second radiator, which can reduce the flow resistance of the coolant and improve the cooling efficiency.

[0069] In some embodiments, in step S230b, the first fluid on-off device may be controlled to cut off the flow between the first fluid channel and the first component to be cooled and the first radiator, while opening the flow between the first connecting pipe and the first component to be cooled and the first radiator. Furthermore, the second fluid on-off device may be controlled to open the flow between the second fluid channel and the second component to be cooled and the second radiator, while cutting off the flow between the second connecting pipe and the second component to be cooled and the second radiator. In this case, the coolant in the first cooling circuit does not exchange heat with the coolant in the second cooling circuit.

[0070] In some embodiments, in step S230b, the first fluid on-off device may be controlled to open the flow path between the first fluid channel and the first component to be cooled and the first radiator, while closing the flow path between the first connecting pipe and the first component to be cooled and the first radiator. Furthermore, the second fluid on-off device may be controlled to close the flow path between the second fluid channel and the second component to be cooled and the second radiator, while opening the flow path between the second connecting pipe and the second component to be cooled and the second radiator. In this case, the coolant in the first cooling circuit and the coolant in the second cooling circuit also do not exchange heat.

[0071] In one embodiment, the heat dissipation capacity of the first heat sink is equal to the maximum heat dissipation demand of all first components to be cooled, and the heat dissipation capacity of the second heat sink is equal to the product of the difference between the maximum total heat dissipation demand of all first components to be cooled and all second components to be cooled, and the maximum heat dissipation demand of all first components to be cooled, and a preset safety factor. That is, the first heat sink is designed according to the maximum heat dissipation demand of all first components to be cooled, ensuring that the cooling capacity of the first heat sink can meet the cooling needs of each first component to be cooled, while the cooling capacity of the second heat sink is determined based on the maximum total heat dissipation demand of all first components to be cooled and all second components to be cooled, and the required safety factor. Because the heat dissipation demand of each subsystem does not reach its maximum simultaneously under normal operating conditions, this approach can save space and cost required for the entire cooling system while simultaneously meeting the heat dissipation needs of each subsystem to the greatest extent possible.

[0072] The preset safety factor is the safety factor actually required, such as 1.1, 1.0, etc.

[0073] It should be noted that the maximum total heat dissipation demand of all first components to be cooled and all second components to be cooled is not equal to the sum of the maximum heat dissipation demand of all first components to be cooled and the maximum heat dissipation demand of all second components to be cooled. This is because under normal operating conditions, the heat dissipation demand of each subsystem will not reach the maximum at the same time.

[0074] In one embodiment, the coupled radiator is a three-medium heat exchanger. In addition to the first fluid channel and the second fluid channel, the coupled radiator also includes a third fluid channel arranged adjacent to the first fluid channel. The third fluid channel is used for cooling air circulation. The air inlet end of the third fluid channel is connected to the air inlet channel of the hybrid vehicle, and the air outlet end of the third fluid channel is connected to the exhaust channel of the hybrid vehicle. Figure 3 A flow chart of a cooling method for a hybrid vehicle provided in the second embodiment of the present application is shown. The cooling method is applicable to a cooling system in which the coupled radiator is a three-medium heat exchanger. The cooling method can be executed by a control device of the hybrid vehicle, such as Figure 3 As shown, the cooling method includes at least the following steps S310 to S330, which are described in detail as follows:

[0075] In step S310, first temperature information detected by a first temperature detection device and second temperature information detected by a second temperature detection device are acquired.

[0076] In step S320, the first temperature information is compared with the first temperature threshold and the second temperature information is compared with the second temperature threshold. When the first temperature information is lower than the first temperature threshold and the second temperature information is higher than the second temperature threshold, it is considered that the cooling capacity of the first cooling circuit is sufficient, but the cooling capacity of the second cooling circuit is insufficient, and the process goes to step S330a. When the second temperature information is lower than the second temperature threshold, it is considered that the cooling capacity of the second cooling circuit is sufficient, and the process goes to step S330b. When the first temperature information is higher than the first temperature threshold and the second temperature information is lower than the second temperature threshold, it is considered that the cooling capacity of the first cooling circuit is insufficient, but the cooling capacity of the second cooling circuit is sufficient, and the process goes to step S330c.

[0077] In step S330a, the first fluid on-off device is controlled to open the flow path between the first fluid channel and the first component to be cooled and the first radiator, and the second fluid on-off device is controlled to open the flow path between the second fluid channel and the second component to be cooled and the second radiator.

[0078] The specific implementation details of step S330a can be found in the description of the aforementioned step S230a, which will not be repeated here.

[0079] In step S330b, the first fluid on-off device is controlled to cut off the flow path between the first fluid channel and the first component to be cooled and the first radiator, and to open the flow path between the first connecting pipeline and the first component to be cooled and the first radiator; and the second fluid on-off device is controlled to cut off the flow path between the second fluid channel and the second component to be cooled and the second radiator, and to open the flow path between the second connecting pipeline and the second component to be cooled and the second radiator.

[0080] The specific implementation details of step S330b can be found in the description of the aforementioned step S230b, which will not be repeated here.

[0081] In step S330c, the first fluid on-off device is controlled to open the flow path between the first fluid channel and the first component to be cooled and the first radiator, and the second fluid on-off device is controlled to cut off the flow path between the second fluid channel and the second component to be cooled and the second radiator.

[0082] At this time, the coolant of the first cooling circuit passes through the first fluid channel, the coolant of the second cooling circuit does not pass through the second fluid channel, and the cooling air through the third fluid channel cools the coolant of the first cooling circuit so that the first temperature information is lower than the first temperature threshold.

[0083] In addition, in step S330c, when controlling the first fluid on-off device to conduct the flow path between the first fluid channel and the first component to be cooled and the first radiator, the first fluid on-off device can be selectively controlled to simultaneously conduct the flow path between the first connecting pipeline and the first component to be cooled and the first radiator, that is, part of the coolant after passing through the first component to be cooled flows to the first radiator through the first fluid channel, and part of the coolant directly flows to the first radiator through the first connecting pipeline; or, the first fluid on-off device can be controlled to cut off the flow path between the first connecting pipeline and the first component to be cooled and the first radiator, that is, all the coolant after passing through the first component to be cooled flows to the first radiator through the first fluid channel.

[0084] In some embodiments, the third fluid channel can be arranged between the first fluid channel and the second fluid channel. The cooling method of the present application further includes: when the first temperature information is higher than the first temperature threshold, and the second temperature information is higher than the second temperature threshold, it is considered that the cooling capacity of the first cooling circuit and the second cooling circuit are insufficient, and the first fluid on-off device is controlled to open the flow path between the first fluid channel and the first component to be cooled and the first radiator, and the second fluid on-off device is controlled to open the flow path between the second fluid channel and the second component to be cooled and the second radiator.

[0085] At this time, the coolant of the first cooling circuit passes through the first fluid channel, the coolant of the second cooling circuit passes through the second fluid channel, and the cooling air passing through the third fluid channel cools the coolant of the first cooling circuit and the second cooling circuit.

[0086] In addition, for the case where the cooling system has more than two cooling circuits, for example, the cooling system has a first cooling circuit, a second cooling circuit and a third cooling circuit, in this case, the coupled radiator can be a radiator with three fluid channels or even four fluid channels, and the third cooling circuit can be provided with a third fluid on-off device, and the cooling method of the present application can also be used.

[0087] See next Figures 4 to 6 , the cooling system of the hybrid vehicle provided by this application is described in detail below.

[0088] Figure 4 The diagram shows the architecture of the cooling system of the hybrid vehicle provided in the first embodiment of the present application. Figure 5 The figure shows a block diagram of some components of the cooling system provided in the first embodiment of the present application. Figure 4 and Figure 5 As shown, the cooling system of this embodiment includes a first cooling circuit, a second cooling circuit, a heat dissipation fan 131 and a control device 141, etc.

[0089] The first cooling circuit, serving as a low-temperature cooling circuit for cooling the power battery, electronic control system, and motor, includes a first temperature detection device 111, a first fluid on / off device 112, a first radiator 113 connected in sequence, a first pump body 114, several first components to dissipate heat (e.g., LQ_1, ..., LQ_N), a first connecting pipe 115 connected in parallel, and a coupling radiator 151. The coupling radiator 151 has a first fluid channel (not shown) and a second fluid channel (not shown). The first fluid on / off device 112 is disposed at one end of the first connecting pipe 115 and the first fluid channel.

[0090] Among them, the first fluid on-off device 112 can be arranged at the liquid inlet end of the first connecting pipeline 115 and the first fluid channel, or can be arranged at the liquid outlet end of the first connecting pipeline 115 and the first fluid channel, for conducting or cutting off the flow path between the first fluid channel and the first component to be cooled and the first radiator 113, and conducting or cutting off the flow path between the first connecting pipeline 115 and the first component to be cooled and the first radiator 113.

[0091] In one embodiment, the first fluid on-off device 112 is an electrically controlled three-way valve having a liquid inlet, a first liquid outlet, and a second liquid outlet. The liquid inlet of the first fluid on-off device 112 is connected to the first component to be cooled, the first liquid outlet of the first fluid on-off device 112 is connected to the first connecting pipeline 115, and the second liquid outlet of the first fluid on-off device 112 is connected to the first fluid channel. The use of an electrically controlled three-way valve for the first fluid on-off device 112 is low-cost and simplifies the control procedures for opening and closing the flow path between the first fluid channel and the first component to be cooled and the first radiator 113, as well as the flow path between the first connecting pipeline 115 and the first component to be cooled and the first radiator 113.

[0092] Of course, in other embodiments, the first fluid on-off device 112 may also include two independently controlled valves, with a valve provided at one end of the first connecting pipe 115 and the first fluid channel respectively, to open or cut off the flow path between the first fluid channel and the first component to be cooled and the first radiator 113, as well as the flow path between the first connecting pipe 115 and the first component to be cooled and the first radiator 113.

[0093] In one embodiment, the first connecting pipe 115 and the first fluid channel are connected to the first radiator 113 via a first tee pipe 116, which can simplify the piping structure of the first cooling circuit. Of course, in other embodiments, the first connecting pipe 115 and the first fluid channel can also be connected to the first radiator 113 via a pipeline respectively.

[0094] The second cooling circuit serves as a high-temperature cooling circuit for cooling the engine, etc., and includes a second temperature detection device 121, a second fluid on-off device 122, a second radiator 123 connected in sequence, a second pump body 124, a plurality of second components to be cooled (such as HQ_1, ..., HQ_N), a second parallel connecting pipe 125 and a coupling radiator 151. The second fluid on-off device 122 is arranged at one end of the second connecting pipe 125 and the second fluid channel.

[0095] Among them, the second fluid on-off device 122 can be arranged at the liquid inlet end of the second connecting pipeline 125 and the second fluid channel, or can be arranged at the liquid outlet end of the second connecting pipeline 125 and the second fluid channel, for conducting or cutting off the flow path between the second fluid channel and the second component to be cooled and the second radiator 123, and conducting or cutting off the flow path between the second connecting pipeline 125 and the second component to be cooled and the second radiator 123.

[0096] In one embodiment, the second fluid on-off device 122 is an electrically controlled three-way valve having a liquid inlet, a first liquid outlet, and a second liquid outlet. The liquid inlet of the second fluid on-off device 122 is connected to the second component to be cooled, the first liquid outlet of the second fluid on-off device 122 is connected to the second connecting pipeline 125, and the second liquid outlet of the second fluid on-off device 122 is connected to the second fluid channel. The use of an electrically controlled three-way valve for the second fluid on-off device 122 is low-cost and simplifies the control procedures for opening and closing the flow path between the second fluid channel and the second component to be cooled and the second radiator 123, as well as the flow path between the second connecting pipeline 125 and the second component to be cooled and the second radiator 123.

[0097] Of course, in other embodiments, the second fluid on-off device 122 may also include two independently controlled valves, with a valve being provided at one end of the second connecting pipe 125 and the second fluid channel respectively to open or cut off the flow path between the second fluid channel and the second component to be cooled and the second radiator 123, as well as the flow path between the second connecting pipe 125 and the second component to be cooled and the second radiator 123.

[0098] In one embodiment, the second connecting pipe 125 and the second fluid channel are connected to the second radiator 123 via a second T-tube 126, which can simplify the piping structure of the second cooling circuit. Of course, in other embodiments, the second connecting pipe 125 and the second fluid channel can also be connected to the second radiator 123 via a pipe respectively.

[0099] The coupling heat sink 151 may include only the first fluid channel and the second fluid channel, such as Figure 4 The cooling system shown can be used for Figure 2The cooling method shown. In this embodiment, the heat dissipation capacity of the first heat sink 113 is equal to the maximum heat dissipation demand of all first components to be cooled, and the heat dissipation capacity of the second heat sink 123 is equal to the product of the difference between the maximum total heat dissipation demand of all first components to be cooled and all second components to be cooled, and the maximum heat dissipation demand of all first components to be cooled, and a preset safety factor. In other words, the first heat sink 113 is designed according to the maximum heat dissipation demand of all first components to be cooled, ensuring that the cooling capacity of the first heat sink 113 can meet the cooling requirements of each first component to be cooled, while the cooling capacity of the second heat sink 123 is determined based on the maximum total heat dissipation demand of all first components to be cooled and all second components to be cooled, and the required safety factor.

[0100] Compared with the prior art, the second radiator 123 of this embodiment has a smaller design size. During operation, the first cooling circuit can always meet the cooling demand. Since the second radiator 123 is not designed according to the maximum heat dissipation demand of the second cooling circuit, a coupling heat exchanger is required to enable the first cooling circuit to pre-cool the coolant of the second cooling circuit. That is, when the heat dissipation demand of the second cooling circuit is the largest, since the heat dissipation demand of the first cooling circuit is not the largest at this time, the first cooling circuit can be used to pre-cool the coolant of the second cooling circuit to make up for the difference.

[0101] The coupled radiator 151 may further include a third fluid channel (not shown in the figure), that is, the coupled radiator 151 is a three-medium radiator (air, low-temperature water, high-temperature water), such as Figure 6 The cooling system shown can be used for Figure 3 The cooling method shown utilizes cooling air to cool the coolant in the first cooling circuit and / or the second cooling circuit, thereby improving the cooling effect.

[0102] The cooling fan 131, the second radiator 123, and the first radiator 113 are arranged side by side. In the air inlet direction, the first radiator 113 is arranged in front of the second radiator 123, and the cooling fan 131 is arranged behind the second radiator 123. The cooling fan 131 accelerates the flow of cooling air in the cooling system, thereby accelerating the cooling of the coolant.

[0103] Control device 141 is electrically connected to first temperature detection device 111, second temperature detection device 121, first fluid on / off device 112, and second fluid on / off device 122. It is configured to control first fluid on / off device 112 and second fluid on / off device 122 based on the temperature information detected by first temperature detection device 111 and second temperature detection device 121, thereby executing the aforementioned cooling method. Control device 141 may be a controller for a hybrid vehicle or any additional electronic device with information processing capabilities.

[0104] In some embodiments, the cooling system may be configured with more than two cooling circuits, such as Figure 7 As shown, the cooling system includes a first cooling circuit, a second cooling circuit, and a third cooling circuit. The first and second cooling circuits are as described above. The third cooling circuit serves as a medium-temperature cooling circuit, used to cool components such as the EGR intercooler. It includes a third radiator 163, a third pump body 164, and several third components to dissipate heat (such as MQ_1, ..., MQ_N) connected in sequence. Similar to the two cooling circuits, coupled heat dissipation can also be achieved through a coupling radiator 151. In this case, the coupling radiator 151 can be a radiator with three or even four fluid channels, or an additional coupling radiator can be provided, with one coupling radiator connected between the first and second cooling circuits, and another coupling radiator connected between the first / second cooling circuit and the third cooling circuit. Of course, the coupling radiator 151 can also be provided only between the first and second cooling circuits, with no coupling radiator provided between the first / second cooling circuit and the third cooling circuit.

[0105] It should be noted that Figure 7 The arrangement of the first radiator 113, the second radiator 123, and the third radiator 163 is only for illustrative purposes and is not limited to the arrangement of the first radiator 113, the second radiator 123, and the third radiator 163 in the specific implementation. Figure 7 Arrangement shown.

[0106] See next Figure 8 , the present application also provides a hybrid vehicle, such as Figure 8 As shown, the hybrid vehicle includes a vehicle body 801 and a cooling system 802. The vehicle body 801 is provided with an air inlet duct 803 for cooling air to enter and an air outlet duct 804 for exhausting the cooling air. The air inlet duct 803 can specifically be located at the front grille of the vehicle body 801. The cooling system 802 is disposed on the vehicle body 801. The air inlet duct 803 and the air outlet duct 804 communicate with a storage space 805 where the cooling system 802 is located. During driving, the cooling air enters the vehicle body 801 through the air inlet duct 803, specifically the storage space 805 where the cooling system 802 is located. The cooling air first passes through the first radiator 113 and then the second radiator 123 of the cooling system 802, where the cooling air accelerates the cooling of the coolant. The cooling air then exits the vehicle body 801 through the air outlet duct 804.

[0107] The specific structure and working principle of the cooling system 802 are described above and will not be repeated here.

[0108] It should be understood that the present application is not limited to the exact structures that have been described above and shown in the drawings, and that various modifications and changes can be performed without departing from the scope thereof. The scope of the present application is limited only by the appended claims.

Claims

1. A cooling method for a hybrid vehicle, characterized in that: The hybrid vehicle includes a first cooling circuit and a second cooling circuit, the first cooling circuit including a first temperature detection device, a first fluid on-off device, a first radiator connected in sequence, a plurality of first components to be cooled, a first connecting pipe connected in parallel, and a coupled radiator, the coupled radiator having a first fluid channel and a second fluid channel, the first fluid on-off device being disposed at one end of the first connecting pipe and the first fluid channel, the second cooling circuit including a second temperature detection device, a second fluid on-off device, a second radiator connected in sequence, a plurality of second components to be cooled, a second connecting pipe connected in parallel, and the coupled radiator, the second fluid on-off device being disposed at one end of the second connecting pipe and the second fluid channel, and the cooling method comprising: Acquire first temperature information detected by the first temperature detection device and second temperature information detected by the second temperature detection device; comparing the first temperature information with a first temperature threshold and the second temperature information with a second temperature threshold, the first temperature threshold being smaller than the second temperature threshold; When the first temperature information is lower than the first temperature threshold and the second temperature information is higher than the second temperature threshold, the first fluid on-off device is controlled to open the flow path between the first fluid channel and the first component to be cooled and the first radiator, and the second fluid on-off device is controlled to open the flow path between the second fluid channel and the second component to be cooled and the second radiator.

2. The cooling method according to claim 1, wherein: The cooling method further comprises: When the second temperature information is lower than the second temperature threshold, controlling the first fluid on-off device to cut off the flow path between the first fluid channel and the first component to be cooled and the first radiator, and to open the flow path between the first connecting pipe and the first component to be cooled and the first radiator; and / or, The second fluid on-off device is controlled to cut off the flow path between the second fluid channel and the second component to be cooled and the second radiator, and to open the flow path between the second connecting pipeline and the second component to be cooled and the second radiator.

3. The cooling method according to claim 1, wherein: The first temperature detection device includes multiple first temperature sensors, each of which is arranged at the liquid inlet end or the liquid outlet end of the first component to be cooled, and the first temperature information is the highest temperature among all the temperature information detected by the multiple first temperature sensors; the second temperature detection device includes multiple second temperature sensors, each of which is arranged at the liquid inlet end or the liquid outlet end of the second component to be cooled, and the second temperature information is the highest temperature among all the temperature information detected by the multiple second temperature sensors.

4. The cooling method according to any one of claims 1 to 3, characterized in that: The heat dissipation capacity of the first radiator is equal to the maximum heat dissipation demand of the several first components to be cooled, and the heat dissipation capacity of the second radiator is equal to the product of the difference between the maximum total heat dissipation demand of the several first components to be cooled and the several second components to be cooled and the maximum heat dissipation demand of the several first components to be cooled multiplied by a preset safety factor.

5. The cooling method according to claim 1, wherein: The coupled radiator includes a third fluid channel, the third fluid channel being used for circulating cooling air, an air inlet end of the third fluid channel being connected to an air inlet channel of the hybrid vehicle, and an air outlet end of the third fluid channel being connected to an air exhaust channel of the hybrid vehicle, and the cooling method further comprising: When the first temperature information is higher than the first temperature threshold and the second temperature information is lower than the second temperature threshold, the first fluid on-off device is controlled to open the flow path between the first fluid channel and the first component to be cooled and the first radiator, and the second fluid on-off device is controlled to cut off the flow path between the second fluid channel and the second component to be cooled and the second radiator.

6. The cooling method according to claim 5, characterized in that: The third fluid channel is provided between the first fluid channel and the second fluid channel, and the cooling method further comprises: When the first temperature information is higher than the first temperature threshold and the second temperature information is higher than the second temperature threshold, the first fluid on-off device is controlled to open the flow path between the first fluid channel and the first component to be cooled and the first radiator, and the second fluid on-off device is controlled to open the flow path between the second fluid channel and the second component to be cooled and the second radiator.

7. The cooling method according to claim 1, wherein: The first temperature threshold is less than or equal to the safe tolerance temperature of the plurality of first components to be cooled, and the second temperature threshold is less than or equal to the safe tolerance temperature of the plurality of second components to be cooled.

8. A cooling system for a hybrid vehicle, characterized in that: The cooling system comprises: a first cooling circuit, the first cooling circuit comprising a first temperature detection device, a first fluid on-off device, a first radiator connected in sequence, a plurality of first heat dissipation components, a first connecting pipe connected in parallel, and a coupling radiator, the coupling radiator having a first fluid channel and a second fluid channel, the first fluid on-off device being disposed at one end of the first connecting pipe and the first fluid channel; a second cooling circuit, the second cooling circuit comprising a second temperature detection device, a second fluid on-off device, a second radiator connected in sequence, a plurality of second components to be cooled, a second connecting pipe connected in parallel, and the coupled radiator, the second fluid on-off device being disposed at one end of the second connecting pipe and the second fluid channel; A control device, the control device is electrically connected to the first temperature detection device, the second temperature detection device, the first fluid on-off device, and the second fluid on-off device, and is configured to perform the cooling method according to any one of claims 1 to 7.

9. The cooling system according to claim 8, characterized in that The first fluid on-off device is an electrically controlled three-way valve, a liquid inlet end of the first fluid on-off device is connected to the first component to be cooled, a first liquid outlet end of the first fluid on-off device is connected to the first connecting pipeline, and a second liquid outlet end of the first fluid on-off device is connected to the first fluid channel. The first connecting pipeline, the first fluid channel and the first radiator are connected via a first three-way pipe. And / or, the second fluid on-off device is an electrically controlled three-way valve, the liquid inlet end of the second fluid on-off device is connected to the second component to be cooled, the first liquid outlet end of the second fluid on-off device is connected to the second connecting pipeline, the second liquid outlet end of the second fluid on-off device is connected to the second fluid channel, and the second connecting pipeline and the second fluid channel are connected to the second radiator through a second three-way pipe.

10. A hybrid vehicle, characterized in that: include: vehicle body; A cooling system is provided on the vehicle body, wherein the cooling system is as described in any one of claims 8 to 9.

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