Cooling system for internal combustion engines

Abstract

To provide a cooling system for an internal combustion engine capable of efficiently cooling the internal combustion engine.SOLUTION: A cooling system for an internal combustion engine includes: a cooling circuit in which cooling water for cooling the internal combustion engine circulates; an electric pump for circulating the cooling water in the cooling circuit; a plurality of components provided in the cooling circuit; a plurality of bypass circuits each provided corresponding to each of the components so that the cooling water bypasses the component; a control valve that switches flowing of the cooling water to either one of the component or the bypass circuit; and a control device that controls opening / closing of the control valve and controls the output of the electric pump. When the cooling water is caused to flow in the component, the control device controls the output of the electric pump on the basis of the type of the component in which the cooling water is caused to flow.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present disclosure relates to a cooling system for an internal combustion engine.

Background Art

[0002] Patent Document 1 discloses a cooling system for an internal combustion engine including a cooling water passage, a pump for circulating cooling water in the cooling water passage, a radiator for cooling the circulating cooling water in the cooling water passage, a valve disposed on the path of the cooling water passage, and a control device for controlling the valve. The cooling water passage includes a passage provided between the pump and the valve, a passage connecting the valve and the radiator, a passage connecting the radiator and the pump, and a passage bypassing the radiator and connecting the valve and the pump.

[0003] The pump disclosed in Patent Document 1 is a mechanical pump, which is connected to a crankshaft that is an output shaft of an internal combustion engine and is driven by the rotational driving force of the crankshaft. Therefore, in a mechanical pump, the output varies depending on the rotation of the internal combustion engine (crankshaft).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] On the other hand, an electric pump can obtain an output regardless of the rotation of the internal combustion engine. However, if the output is made constant, the internal combustion engine cannot be efficiently cooled.

[0006] In view of the above circumstances, at least one embodiment of the present invention aims to provide a cooling system for an internal combustion engine that can efficiently cool the internal combustion engine.

Means for Solving the Problems

[0007] (1) A cooling system for an internal combustion engine according to at least one embodiment of the present invention includes: a cooling circuit through which cooling water for cooling the internal combustion engine circulates; an electric pump for circulating the cooling water in the cooling circuit; a plurality of components provided in the cooling circuit; a plurality of bypass circuits provided corresponding to each component so that the cooling water bypasses each of the components; and the cooling water but The aforementioned component The state of flowing and The cooling water The bypass circuit A state where it flows only to The system includes a control valve that switches between one of the two states, and a control device that controls the opening and closing of the control valve and also controls the output of the electric pump, wherein the control device controls the output of the electric pump based on the type of component through which the cooling water is circulated when the cooling water is circulated through the component.

[0008] According to the configuration described in (1) above, when circulating coolant through components, the output of the electric pump is controlled based on the type of component through which the coolant is circulated, thereby enabling efficient cooling of the internal combustion engine.

[0009] (2) In some embodiments, in the configuration of (1) above, if the component is of a type that is in contact with the body of the internal combustion engine, the output of the electric pump is controlled such that when the temperature of the body of the internal combustion engine is above a predetermined temperature, the output of the electric pump is greater than when the temperature of the internal combustion engine is below the predetermined temperature.

[0010] According to the configuration described in (2) above, if the component is of a type that comes into contact with the body of the internal combustion engine, when the temperature of the body of the internal combustion engine is above a predetermined temperature, the output of the electric pump becomes greater than when the temperature of the internal combustion engine is below the predetermined temperature, so the component can be cooled efficiently.

[0011] (3) In some embodiments, in the configuration of (1) above, the control device controls the output of the electric pump so that when the pressure loss of the component through which the cooling water flows exceeds a predetermined pressure loss (reference value), the output of the electric pump increases by a predetermined amount.

[0012] According to the configuration described in (3) above, when the pressure loss of the component through which the cooling water circulates exceeds a predetermined pressure loss, the output of the electric pump increases by a predetermined amount, thereby enabling efficient cooling of the internal combustion engine.

[0013] (4) In some embodiments, in the configuration of (1) above, the control device controls the output of the electric pump so that when the volume of the cooling water circulating in the component exceeds a predetermined volume (reference value), the output of the electric pump increases by a predetermined amount.

[0014] According to the configuration described in (4) above, when the volume of coolant circulating in the component that distributes the coolant exceeds a predetermined volume, the output of the electric pump increases by a predetermined amount, thereby enabling efficient cooling of the internal combustion engine.

[0015] (5) In some embodiments, in any one of the configurations (1) to (4) above, the plurality of components include an EGR cooler for cooling the recirculating exhaust gas, and the control device controls the output of the electric pump to maintain the output of the electric pump as if the coolant were flowing through the EGR cooler, even when the coolant is bypassing the EGR cooler, during high-load operation of the internal combustion engine.

[0016] According to the configuration described in (5) above, even when the coolant bypasses the EGR cooler, the output of the electric pump is maintained at the same level as when the coolant flows through the EGR cooler during high-load operation of the internal combustion engine, thereby maintaining a high cooling capacity for the internal combustion engine.

[0017] (6) In some embodiments, in any one of the configurations (1) to (4) above, the at least one component is an EGR cooler for cooling the recirculating exhaust gas, and is mounted on a hybrid vehicle capable of selecting a series running mode in which a driving motor supplied with electric power generated by an internal combustion engine drives drive wheels, or a parallel running mode in which the internal combustion engine and the driving motor drive the drive wheels. When the cooling water bypasses the EGR cooler and the parallel running mode is selected, the output of the electric pump is controlled so as to maintain the output of the electric pump when the cooling water flows through the EGR cooler.

[0018] According to the configuration (6) above, even when the cooling water bypasses the EGR cooler and the parallel running mode is selected, the output of the electric pump when the cooling water flows through the EGR cooler is maintained, so that the cooling capacity of the internal combustion engine can be maintained at a high level.

[0019] (7) In some embodiments, in any one of the configurations (1) to (4) above, the control valve is a flow control valve that controls the flow rate of the cooling water to the component and the bypass circuit, and the control device determines the output of the electric pump based on the sum of the values obtained by multiplying the coefficients preset for the plurality of components by the opening degree of the flow control valve.

[0020] According to the configuration (7) above, since the output of the electric pump is determined based on the sum of the values obtained by multiplying the coefficients preset for the plurality of components by the opening degree of the flow control valve, the internal combustion engine can be efficiently cooled.

Effect of the Invention

[0021] According to at least one embodiment of the present invention, the internal combustion engine can be efficiently cooled.

Brief Description of the Drawings

[0022] [Figure 1] It is a schematic diagram showing a vehicle equipped with an internal combustion engine according to Embodiment 1. [Figure 2] Figure 1 is a block diagram showing the cooling system of an internal combustion engine. [Figure 3] This is a block diagram showing the cooling system for an internal combustion engine according to Embodiment 2. [Modes for carrying out the invention]

[0023] Embodiments of the present invention will be described below with reference to the attached drawings. However, the dimensions, materials, shapes, relative arrangements, etc., of the components described as embodiments or shown in the drawings are not intended to limit the scope of the present invention, but are merely illustrative examples.

[0024] [Embodiment 1] Figure 1 is a schematic diagram showing a vehicle equipped with an internal combustion engine according to Embodiment 1. Figure 2 is a block diagram showing the cooling system of the internal combustion engine shown in Figure 1.

[0025] As shown in Figure 1, the vehicle 1 equipped with the internal combustion engine 10 according to Embodiment 1 is a hybrid vehicle powered by the internal combustion engine 10 and the drive motors 12 and 14, but is not limited to this, and may be an engine vehicle powered solely by the internal combustion engine 10. The internal combustion engine 10 has a cylinder block 32 and a cylinder head 34. The vehicle 1 is equipped with a generator 16 driven by the internal combustion engine 10 and a drive battery 18 that charges the electricity generated by the generator 16. Such a vehicle 1 can select between a series driving mode in which the drive motors 12 and 14 drive the drive wheels 20 and 22 with electricity supplied from the generator 16, or a parallel driving mode in which the internal combustion engine 10 and the drive motors 12 and 14 drive the drive wheels 20. The hybrid vehicle 1 shown in Figure 1 is a four-wheel drive hybrid vehicle, but is not limited to this, and may be a two-wheel drive hybrid vehicle.

[0026] As shown in Figure 2, the internal combustion engine 10 according to Embodiment 1 is equipped with a cooling system 24A for cooling the internal combustion engine 10. The cooling system 24A includes a cooling circuit 26 through which cooling water circulates to cool the internal combustion engine 10, an electric pump 28 that circulates the cooling water in the cooling circuit 26, and a plurality of components 30 provided in the cooling circuit 26. The plurality of components 30 are, for example, a cylinder block 32 and a radiator 36, which are part of the internal combustion engine 10, and these are provided in the cooling circuit 26. The electric pump 28 is a pump driven by electricity supplied from an auxiliary battery (not shown) and can be operated separately from the operation of the internal combustion engine 10.

[0027] Furthermore, the cooling system 24A of the internal combustion engine 10 according to Embodiment 1 includes a plurality of bypass circuits 38 provided corresponding to each component 30 so that the coolant bypasses each component 30, and a control valve 40 that switches the flow of the coolant between the component 30 and the bypass circuits 38. The bypass circuits 38 include, for example, a bypass circuit 42 that bypasses the radiator 36 and a bypass circuit 44 that bypasses the cylinder block 32. When the coolant bypasses the radiator 36, the coolant flows through the bypass circuit 42, and when the coolant bypasses the cylinder block 32, the coolant flows through the bypass circuit 44. The bypass circuit 44 includes the cylinder head 34, and even when the coolant flows to the cylinder block 32 (when the control valve 48, described later, is fully open), the coolant also flows to the cylinder head 34. Furthermore, when the coolant bypasses the radiator 36 and cylinder block 32, the entire amount of coolant may flow through the bypass circuit 42 and cylinder head 34, or only a portion of it may flow through the bypass circuit 42 and cylinder head 34.

[0028] A control valve 46 provided for a bypass circuit 42 that bypasses the radiator 36 is, for example, provided at the branching point between the circuit to which the radiator 36 is connected and the bypass circuit 42 that bypasses the radiator 36. A control valve 48 provided for a bypass circuit 44 that bypasses the cylinder block 32 is, for example, provided downstream or upstream of the cylinder block 32.

[0029] Furthermore, the cooling system 24A of the internal combustion engine 10 according to Embodiment 1 includes a control device 50 that controls the opening and closing of the control valve 40 and also controls the output of the electric pump 28. The control device 50 consists of a processor (not shown) comprising an arithmetic unit, registers for storing instructions and information, and peripheral circuits, a memory (not shown) such as ROM (Read Only Memory) and RAM (Random Access Memory), and an input interface (not shown). When the control device 50 circulates coolant through a component 30, it controls the output of the electric pump 28 based on the type of component 30 through which the coolant is circulated. For example, components 30 through which coolant can be bypassed include the radiator 36 and the cylinder block 32, and when the control device 50 circulates coolant through these bypassable components 30, it controls the output of the electric pump 28 based on the type of component 30 through which the coolant is circulated.

[0030] For example, the control device 50 controls the output of the electric pump 28 so that when the pressure loss of the component 30 through which the cooling water flows exceeds a predetermined pressure loss (reference value), the output of the electric pump 28 increases by a predetermined amount. The pressure loss of component 30 is measured under predetermined conditions. These predetermined conditions include, for example, that the temperature of the cooling water is constant. The pressure loss ΔP varies depending on the pipe friction coefficient λ, pipe length l, pipe diameter d, fluid density ρ, and average flow velocity u, as shown in Equation 1 below. However, if the temperature of the cooling water changes, for example, the fluid density ρ changes, and therefore the pressure loss ΔP also changes. Thus, it is necessary to compare the pressure loss ΔP under predetermined conditions.

[0031]

number

[0032] For example, the control device 50 controls the output of the electric pump 28 so that when the volume of coolant remaining in the component 30 through which the coolant flows exceeds a predetermined volume (reference value), the output of the electric pump 28 increases by a predetermined amount. The volume of coolant remaining in the component 30 is the amount of coolant remaining in the component 30 when the operation of the electric pump 28 is stopped, and is usually recognized as the volume of the component 30. The predetermined volume is, for example, the volume that allows one to determine whether or not the component 30 is a heat exchanger. Heat exchangers increase the volume of coolant because they promote heat exchange between the coolant and other heat transfer media by increasing the surface area. Also, if the component 30 is a heat exchanger, the predetermined volume may be, for example, the volume that allows one to determine whether or not the heat exchanger is large. A large heat exchanger is, for example, a radiator 36, while a heat exchanger that is not large is, for example, an oil cooler or an EGR cooler.

[0033] The control valve 40 may be a flow control valve that controls the flow rate of cooling water to the component 30 and the bypass circuit 38. For example, by changing the opening degree of the control valve 40, the flow area to the component 30 and the bypass circuit 38 is changed. In this case, the control device 50 determines the output of the electric pump 28 based on the sum of the values ​​obtained by multiplying the preset flow rate for each component 30 by the opening degree of the control valve 40.

[0034] Specifically, the output (flow rate) of the electric pump when the coolant bypasses the radiator 36 and cylinder block 32 is V. BASE The opening degree of control valve 48 is set to K1, the opening degree of control valve 46 is set to K2, and the preset flow rate is set to V. C / B A preset flow rate is applied to the cylinder block 32. C / B A pre-set flow rate is applied to the radiator 36. RADTherefore, the output V of the electric pump 28 W / P This can be expressed by the following equation 2.

[0035]

number

[0036] If we replace this with the rotational speed NE of the electric pump 28, it can be expressed by the following equation 3.

[0037]

number

[0038] According to the cooling system 24A for the internal combustion engine 10 of Embodiment 1, when cooling water is circulated through the component 30, the output of the electric pump 28 is controlled based on the type of component 30 through which the cooling water is circulated, thereby enabling efficient cooling of the internal combustion engine 10. In other words, when cooling water is not circulated through the component 30, the output of the electric pump 28 is reduced to suppress overcooling of the internal combustion engine 10 and to reduce power consumption by the electric pump 28.

[0039] For example, if the pressure loss of the component 30 through which the cooling water flows exceeds a predetermined pressure loss, the output of the electric pump 28 increases by a predetermined amount, thereby efficiently cooling the internal combustion engine 10. In other words, if the pressure loss of the component 30 through which the cooling water flows is large, the output of the electric pump 28 is increased in proportion to that pressure loss, so that sufficient cooling water can be supplied to the internal combustion engine 10 and the component 30. On the other hand, if cooling water is not circulated through the component 30 with a large pressure loss, the output of the electric pump 28 is reduced, thereby suppressing overcooling of the internal combustion engine 10 and reducing power consumption by the electric pump 28.

[0040] For example, if the volume of coolant circulating in component 30 exceeds a predetermined volume, the output of the electric pump 28 increases by a predetermined amount, thereby efficiently cooling the internal combustion engine 10. In other words, if the volume of component 30 through which coolant circulates is large, the flow rate of coolant circulating in other cooling circuits decreases compared to when coolant is not circulated through component 30, so the output of the electric pump 28 is increased in accordance with the volume of component 30. On the other hand, if coolant is not circulated through the large-capacity component 30, the output of the electric pump 28 is reduced, thereby suppressing overcooling of the internal combustion engine 10 and reducing power consumption by the electric pump 28.

[0041] For example, if the control valve 40 is a flow control valve that controls the flow rate of cooling water, the output of the electric pump 28 is determined based on the sum of the values ​​obtained by multiplying a predetermined coefficient for multiple components 30 by the opening degree of the control valve 40, thereby efficiently cooling the internal combustion engine 10. In other words, the output of the electric pump 28 is determined according to the opening degree of the control valve 40, or in other words, the flow rate of cooling water flowing through the components 30. At this time, the required flow rate (coefficient) for each component 30 is also taken into consideration, so the internal combustion engine 10 can be efficiently cooled.

[0042] [Embodiment 2] Figure 3 is a block diagram showing the cooling system for an internal combustion engine according to Embodiment 2. Components identical to those in the cooling system 24A of the internal combustion engine 10 according to Embodiment 1 are denoted by the same reference numerals and their descriptions are omitted.

[0043] As shown in Figure 3, in the cooling system 24B for the internal combustion engine 10 according to Embodiment 2, the multiple components 30 include, in addition to those in Embodiment 1, an oil cooler 52 for cooling the oil used to lubricate the internal combustion engine 10, and an EGR cooler 54 for cooling the recirculating exhaust gas, and these are provided in the cooling circuit 26. Furthermore, the cooling system 24B for the internal combustion engine according to Embodiment 2 includes a bypass circuit 56 through which the cooling water bypasses the EGR cooler 54, and a control valve 58 that switches the flow of the cooling water between the EGR cooler 54 and the bypass circuit 56. When the cooling water bypasses the EGR cooler 54, the cooling water flows through the bypass circuit 56. Note that when the cooling water bypasses the EGR cooler 54, the entire amount of cooling water may flow through the bypass circuit 56, or only a portion may flow through the bypass circuit 56.

[0044] The control valve 58 provided for the bypass circuit 56 is, for example, provided at the junction of the circuit connected to the EGR cooler 54 and the bypass circuit 56 that bypasses the EGR cooler 54.

[0045] In the cooling system 24B of the internal combustion engine 10 according to Embodiment 2, the control device 50 controls the output of the electric pump 28 to maintain the output of the electric pump 28 when the cooling water is flowing through the EGR cooler 54, even when the cooling water is bypassing the EGR cooler 54, during high-load operation of the internal combustion engine 10. That is, during low-load operation of the internal combustion engine 10, when the cooling water bypasses the EGR cooler 54, the output of the electric pump 28 is reduced compared to when the cooling water does not bypass the EGR cooler 54. On the other hand, during high-load operation of the internal combustion engine 10, even when the cooling water bypasses the EGR cooler 54, the output of the electric pump 28 is set to be the same as when the cooling water does not bypass the EGR cooler 54. High-load operation of the internal combustion engine 10 occurs, for example, when the vehicle speed exceeds a predetermined speed, or when the rotational speed of the internal combustion engine 10 exceeds a predetermined rotational speed. Therefore, for example, high-load operation occurs when a vehicle is traveling on a highway or when a vehicle is traveling in an uphill lane.

[0046] For example, if the component 30 is of a type that comes into contact with the body of the internal combustion engine 10, the control device 50 controls the output of the electric pump 28 so that when the temperature of the body of the internal combustion engine 10 is above a predetermined temperature, the output of the electric pump 28 is greater than when the temperature of the internal combustion engine 10 is below a predetermined temperature. The "body of the internal combustion engine 10" refers to the cylinder block 32 and the cylinder head 34. The "component 30 that comes into contact with the body of the internal combustion engine 10" includes, for example, the cylinder block 32 fixed to the cylinder head 34 and the oil cooler 52 fixed to the cylinder block 32. Note that the "component 30 that comes into contact with the body of the internal combustion engine 10" is not limited to those fixed to the body of the internal combustion engine 10, but also includes components 30 that come into contact with the cylinder block 32 or the cylinder head 34.

[0047] For example, the control device 50 controls the output of the electric pump 28 to maintain the output of the electric pump 28 when the coolant is flowing through the EGR cooler 54, even when the coolant is bypassing the EGR cooler 54, if the parallel driving mode is selected. In this embodiment, in series driving mode, the output of the electric pump 28 is controlled based on the type of component 30 through which the coolant is flowing, similar to Embodiment 1. On the other hand, in parallel driving mode, the output of the electric pump 28 is generally controlled based on the type of component 30 through which the coolant is flowing, but when the component 30 through which the coolant is flowing is the EGR cooler 54, the output of the electric pump 28 is not changed depending on whether the coolant is passing through the EGR cooler 54 or bypassing the EGR cooler 54.

[0048] Similar to Embodiment 1, when the control valve 40 is a flow control valve that controls the flow rate of cooling water to the component 30 and the bypass circuit 38, the control device 50 determines the output of the electric pump 28 based on the sum of the values ​​obtained by multiplying the preset flow rate for each component 30 by the opening degree of the control valve 40. In this embodiment, an EGR cooler 54 is added as a component 30 to which the bypass circuit 38 is provided, compared to Embodiment 1. Therefore, Equation 2 is modified by the opening degree K3 of the control valve 58 and the preset flow rate V for the EGR cooler 54. EGR The output V of the electric pump 28 is calculated by adding the cumulative values ​​of the above. W / P Calculate.

[0049] According to the cooling system 24B for the internal combustion engine 10 of Embodiment 2, even when the cooling water bypasses the EGR cooler 54, the output of the electric pump 28 is maintained at the same level as when the cooling water flows through the EGR cooler 54 during high-load operation of the internal combustion engine 10, thereby maintaining a high cooling capacity for the internal combustion engine 10.

[0050] For example, if component 30 is of a type that comes into contact with the body of the internal combustion engine 10, when the temperature of the body of the internal combustion engine 10 is above a predetermined temperature, the output of the electric pump 28 will be greater than when the temperature of the internal combustion engine 10 is below the predetermined temperature, so component 30 can be cooled efficiently. Since component 30 that comes into contact with the body of the internal combustion engine 10 is affected by the heat of the internal combustion engine 10, the output of the electric pump 28 is increased when the internal combustion engine 10 is hot. On the other hand, when the internal combustion engine 10 is cold, even component 30 that comes into contact with the body of the internal combustion engine 10 is less affected by the heat of the internal combustion engine 10, so there is no need to increase the output of the electric pump 28.

[0051] For example, even when the coolant bypasses the EGR cooler 54, if the parallel driving mode is selected, the output of the electric pump 28 is maintained as if the coolant were circulating through the EGR cooler 54, thus maintaining a high cooling capacity for the internal combustion engine 10. In parallel driving mode, the output of the internal combustion engine 10 changes according to the driving conditions of the vehicle 1, but the output of the internal combustion engine 10 in series driving mode is approximately constant and is often lower than in parallel driving mode. Therefore, when the parallel driving mode is selected, even when the coolant bypasses the EGR cooler 54, the output of the electric pump 28 is maintained as if the coolant were circulating through the EGR cooler 54, thereby adequately cooling the internal combustion engine 10 in parallel driving mode. [Explanation of Symbols]

[0052] 1 vehicle 10 Internal combustion engine 12,14 Driving motor 16 Generators 18. Battery for driving 20, 22 drive wheels 24 Cooling System 26 Cooling circuit 28 Electric pump 30 components 32 Cylinder Block 34 Cylinder head 36 Radiator 38 Bypass Circuit 40 Control valve 42 Bypass circuit to bypass the radiator 44 Bypass circuit that bypasses the cylinder block 46 Control valve provided for a bypass circuit that bypasses the radiator. 48 Control valve provided for a bypass circuit that bypasses the cylinder block 50 Control device 52 Oil cooler 54 EGR cooler 56 Bypass circuit to bypass the EGR cooler 58 Control valve provided for the bypass circuit that bypasses the EGR cooler

Claims

1. A cooling circuit through which coolant circulates to cool an internal combustion engine, The cooling circuit includes an electric pump for circulating the cooling water, Multiple components provided in the cooling circuit, Multiple bypass circuits are provided corresponding to each component so that the cooling water bypasses each of the components, A control valve that switches between a state in which the cooling water flows to the component and a state in which the cooling water flows only to the bypass circuit, A control device that controls the opening and closing of the control valve and the output of the electric pump, Equipped with, The control device controls the output of the electric pump based on the type of component through which the cooling water is circulated when the cooling water is circulated through the component. Cooling system for an internal combustion engine.

2. If the component is of a type that is in contact with the body of the internal combustion engine, When the temperature of the internal combustion engine body is above a predetermined temperature, the output of the electric pump is controlled to be greater than when the temperature of the internal combustion engine is below the predetermined temperature. Cooling system for an internal combustion engine according to claim 1.

3. The control device controls the output of the electric pump so that when the pressure loss of the component through which the cooling water flows exceeds a predetermined pressure loss, the output of the electric pump increases by a predetermined amount. Cooling system for an internal combustion engine according to claim 1.

4. The control device controls the output of the electric pump so that when the volume of the cooling water circulating in the component exceeds a predetermined volume, the output of the electric pump increases by a predetermined amount. Cooling system for an internal combustion engine according to claim 1.

5. The aforementioned plurality of components include an EGR cooler for cooling the recirculated exhaust gas. The control device controls the output of the electric pump to maintain the output of the electric pump as if the coolant were flowing through the EGR cooler, even when the coolant is bypassing the EGR cooler, during high-load operation of the internal combustion engine. A cooling system for an internal combustion engine according to any one of claims 1 to 4.

6. The aforementioned plurality of components include an EGR cooler for cooling the recirculated exhaust gas. It is installed in a hybrid vehicle that can select between a series driving mode in which a drive motor, supplied with electricity generated by an internal combustion engine, drives the drive wheels, or a parallel driving mode in which the internal combustion engine and the drive motor drive the drive wheels. Even when the coolant bypasses the EGR cooler, if the parallel driving mode is selected, the output of the electric pump is controlled to maintain the output of the electric pump as if the coolant were flowing through the EGR cooler. A cooling system for an internal combustion engine according to any one of claims 1 to 4.

7. The control valve is a flow control valve that controls the flow rate of the cooling water to the component and the bypass circuit, The control device determines the output of the electric pump based on the sum of the values ​​obtained by multiplying the plurality of components by a predetermined coefficient and the opening degree of the flow control valve. A cooling system for an internal combustion engine according to any one of claims 1 to 4.

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