Temperature control system, temperature control method and vehicle

Abstract

A temperature control system comprises: a first cooling circuit (14) in which a first cooling medium circulates, the first cooling circuit being used for cooling a first structural unit (11); a second cooling medium flows in the second cooling loop (15), and the second cooling loop is used for cooling the second structural units (12 and 13); and the heat exchanger (16) is respectively communicated with the first cooling loop and the second cooling loop and is used for carrying out heat exchange between the first cooling medium and the second cooling medium. The first cooling loop comprises a bypass branch (141), and the bypass branch is connected with the heat exchanger in parallel. According to the temperature control system, the heat dissipation efficiency of the inverter and the overall heat dissipation capability of the power assembly are improved.

Description

[0001] This application is a divisional application. The application number of the original application is 202080032600.X, and the original application date is March 30, 2020. The entire contents of the original application are incorporated into this application by reference. Technical Field

[0002] The present application relates to the field of temperature control of electric vehicles, and specifically to a temperature control system, a temperature control method and a vehicle. Background Art

[0003] The powertrain of an electric vehicle includes: a motor (electric motor), a direct current (DC)-alternating current (AC) inverter, a motor control system, and a reducer. Among them, when dissipating heat from the powertrain of an electric vehicle, the existing technology usually dissipates heat from the motor and reducer through an oil cooling circuit, dissipates heat from the inverter through a water cooling circuit, and transfers the heat from the oil cooling circuit to the water cooling circuit through an oil-water heat exchanger. At present, driven by the market, the powertrain is moving towards miniaturization. This means that the maximum speed of the assembly needs to be increased to output the same power as the existing powertrain. The same power in a smaller volume means an increase in heat consumption density. How to dissipate heat out of the system in a timely and efficient manner has become a bottleneck restricting the miniaturization of the assembly. Therefore, heat dissipation technology is one of the key technologies for miniaturization of electric vehicle powertrains.

[0004] Specifically, when a large current is applied to the inverter (i.e., low-speed peak torque), the inverter core is at risk of overheating, and the heat dissipation capacity is usually improved by increasing the fin density of the inverter heat sink or increasing the cooling flow rate. When the motor is running at high speed, both the magnet and the coil are at risk of overheating, and the heat dissipation capacity is usually improved by increasing the fin density of the oil-water heat exchanger or increasing the cooling flow rate.

[0005] Since the water cooling cycle power (i.e., water pump power) of the vehicle thermal management is rated, increasing the fin density of the inverter heat sink and the fin density of the oil-water heat exchanger can improve the heat dissipation capacity of the inverter radiator and the oil-water heat exchanger. However, this solution will significantly increase the flow resistance of the cooling water when it circulates in the inverter radiator and the oil-water heat exchanger, resulting in a decrease in the coolant flow rate at the same water pump output power, making it impossible to increase the heat dissipation capacity of the powertrain when the water pump power is constant. In addition, if the fin density of the inverter heat sink is increased, the hardware and process costs will also be high; on the other hand, if the fin density of the oil-water heat exchanger is increased, not only will the cost increase, but the volume will also increase further, thereby restricting the powertrain success rate volume density.

[0006] Therefore, a more effective and low-cost temperature control solution for electric vehicles is needed. Summary of the invention

[0007] The embodiments of the present application aim to provide a more effective temperature control system for electric vehicles to address the deficiencies in the prior art.

[0008] To achieve the above-mentioned purpose, the present application provides a temperature control system on one hand, comprising: a first cooling circuit, a first cooling medium flows in the first cooling circuit, and the first cooling circuit is used to cool the first structural unit; a second cooling circuit, a second cooling medium flows in the second cooling circuit, and the second cooling circuit is used to cool the second structural unit; a heat exchanger, which is respectively connected to the first cooling circuit and the second cooling circuit, and is used to perform heat exchange between the first cooling medium and the second cooling medium; the first cooling circuit includes a bypass branch, and the bypass branch is connected in parallel with the heat exchanger. The temperature control system is used, for example, to dissipate heat for the powertrain of an electric vehicle, the first structural unit is, for example, an inverter in an electric vehicle, and the second structural unit is, for example, a motor and / or a motor reducer in the electric vehicle. The heat exchanger is, for example, an oil-water heat exchanger, which is used to exchange heat with the cooling oil (i.e., the second cooling medium) in the oil cooling circuit (i.e., the second cooling circuit) through the cooling water (i.e., the first cooling circuit) in the water cooling circuit, and the bypass branch is, for example, implemented as a bypass pipe. By using a bypass pipe to short-circuit the heat exchanger, the heat exchanger is completely or partially short-circuited, thereby reducing the system flow resistance, increasing the water flow rate in the water cooling circuit, and increasing the water flow rate in the water cooling circuit (that is, the amount of fluid flowing through a closed pipe per unit time), thereby enhancing the heat dissipation efficiency of the water cooling circuit for the inverter.

[0009] In one embodiment, a valve is provided in the first cooling circuit, and the valve is connected to the bypass branch, and is used to control the flow distribution of the first cooling medium to the heat exchanger and the bypass branch. By using the valve to control the flow percentage in the bypass pipe, the valve can be controlled to change the flow resistance in the water cooling circuit according to the heat dissipation requirements of each component in the powertrain of the electric vehicle, so that the heat dissipation of each component in the powertrain can be comprehensively considered, and the overall heat dissipation capacity of the temperature control system can be improved.

[0010] In one embodiment, the first structural unit is an inverter in an electric vehicle, and the valve is a controllable valve, which is controlled to increase the flow percentage of the first cooling medium flowing to the bypass branch during the process of increasing the heating power of the inverter or when the heating power of the inverter is about to increase. By controlling the valve to increase the flow percentage of the water flow in the water cooling circuit flowing into the bypass pipe during the process of increasing the heating power of the inverter or when the heating power of the inverter is about to increase, the flow resistance in the water cooling circuit is reduced to increase the flow rate of the entire water cooling circuit, thereby improving the heat dissipation efficiency of the inverter. In addition, while the flow in the water cooling circuit is increased, the heat exchange of the oil cooling circuit in the heat exchanger is reduced or stopped, and the motor can temporarily rely on its own heat capacity to maintain the current operating state for a period of time. Therefore, although increasing the percentage of water flow in the bypass pipe reduces the water flow flowing into the heat exchanger for heat exchange of the oil cooling circuit, the risk of overheating of the motor in a short time is low.

[0011] In one embodiment, the valve is controlled to reduce the flow percentage of the first cooling medium flowing to the bypass branch after the heating power of the inverter is reduced. After the heating power of the inverter is reduced, the over-temperature risk of the inverter is reduced. At the same time, under certain working conditions, the motor speed is high, the heating power of the motor is high, and there is a risk of over-temperature. Therefore, by controlling the valve to reduce the percentage of water flow in the bypass pipe, that is, allowing more water per unit time to flow into the heat exchanger to perform heat exchange on the oil cooling circuit, the heat exchange capacity of the motor is improved to avoid over-temperature of the motor.

[0012] In one embodiment, the valve is controlled to increase the flow percentage of the first cooling medium flowing to the bypass branch to a first percentage when the electric vehicle is about to reach a first predetermined operating condition. By dividing the operating conditions in the powertrain of the electric vehicle into at least two operating conditions, the valve state can be controlled by determining whether a specific operating condition is reached. Before reaching the first predetermined operating condition, it indicates that the heating power of the inverter will be greater than or equal to a predetermined value, so the state of the valve can be adjusted to increase the percentage of water flow flowing into the bypass component to increase the water flow rate in the water cooling circuit, thereby improving the heat dissipation efficiency of the inverter.

[0013] In one embodiment, the valve is controlled to increase the flow percentage of the first cooling medium flowing to the bypass branch to a second percentage when the electric vehicle is about to reach a second predetermined operating condition, wherein the heating power of the inverter corresponding to the first predetermined operating condition is higher than the heating power of the inverter corresponding to the second predetermined operating condition, and the first percentage is greater than the second percentage. In this embodiment, the operating conditions of the powertrain are divided into at least three operating conditions, wherein each operating condition corresponds to a different heating power interval of the inverter. Thus, in the case where the heating power of the inverter corresponding to the first predetermined operating condition is greater than the heating power of the inverter corresponding to the second predetermined operating condition, the opening size of the valve can be adjusted accordingly, so that the valve can be adaptively adjusted with respect to multiple heating power intervals of the inverter, and the valve is adjusted to make the percentage of water flow in the bypass pipe larger for the operating condition corresponding to the higher heating power interval, and the valve is adjusted to make the percentage of water flow in the bypass pipe smaller for the operating condition corresponding to the lower heating power, so that the adjustment of the valve is more finely adapted to the change of the heating power of the inverter.

[0014] In one embodiment, the valve is controlled to reduce the flow percentage of the first cooling medium flowing to the bypass branch to a third percentage after the electric vehicle reaches a third predetermined operating condition.

[0015] In one implementation, the first predetermined operating condition, the second predetermined operating condition and the third predetermined operating condition are determined based on any one or more of the following: motor torque, motor speed, motor power, motor heating power, motor stator current, inverter temperature, inverter heating power, motor temperature. Thus, the control of the valve can be determined by a variety of measurement methods and corresponding hardware configurations, so that the temperature control system of the present application has a variety of implementation forms.

[0016] In one embodiment, the valve is a two-way valve or a three-way valve. Corresponding to different valves, the temperature control system also has different pipelines and connections between pipelines. The temperature control system may also not include the valve. Different configurations of the temperature control system may have different manufacturing costs and volumes. Therefore, different configurations may be selected according to the needs of specific vehicle models to implement the temperature control system of the present application.

[0017] On the other hand, the present application provides a temperature control method, which is performed based on the above-mentioned temperature control system, including: determining the changes that will occur in the heating power of the inverter; when it is determined that the heating power of the inverter will increase, during the process of increasing the heating power of the inverter or before the heating power of the inverter increases, controlling the valve to increase the flow percentage of the first cooling medium flowing to the bypass branch.

[0018] In one embodiment, the method further includes, in a case where it is determined that the heating power of the inverter is to be reduced, controlling the valve to reduce the flow percentage of the first cooling medium flowing to the bypass branch after the heating power of the inverter is reduced.

[0019] In one embodiment, during the process of increasing the heating power of the inverter or before the heating power of the inverter increases, controlling the valve to increase the flow percentage of the first cooling medium flowing to the bypass branch includes: before the electric vehicle reaches a first predetermined operating condition, controlling the valve to increase the flow percentage of the first cooling medium flowing to the bypass branch to a first percentage.

[0020] In one embodiment, during the process of increasing the heating power of the inverter or before the heating power of the inverter increases, controlling the valve to increase the flow percentage of the first cooling medium flowing to the bypass branch also includes: when the electric vehicle is about to reach a second predetermined operating condition, controlling the valve to increase the flow percentage of the first cooling medium flowing to the bypass branch to a second percentage, wherein the heating power of the inverter corresponding to the first predetermined operating condition is higher than the heating power of the inverter corresponding to the second predetermined operating condition, and the first percentage is greater than the second percentage.

[0021] In one embodiment, after the heating power of the inverter is reduced, controlling the valve to reduce the flow percentage of the first cooling medium flowing to the bypass branch includes: after the electric vehicle reaches a third predetermined operating condition, controlling the valve to reduce the flow percentage of the first cooling medium flowing to the bypass branch to a third percentage.

[0022] On the other hand, the present application provides a chip, which includes a processor and an interface circuit, wherein the interface circuit is coupled to the processor, and the processor is used to run a computer program or instruction to implement any of the above-mentioned temperature control methods.

[0023] On the other hand, the present application provides a vehicle, which includes any one of the above-mentioned temperature control systems, wherein the first structural unit is specifically an inverter in the vehicle, and the second structural unit includes an electric motor in the vehicle.

[0024] According to the temperature control system of the present application, when the motor has a low speed and a large torque (peak current), the short-term water cooling circulation flow rate is increased by 1-2 times by bypassing (short-circuiting) the heat exchanger water circuit and the large heat capacity of the motor itself, thereby improving the short-term heat dissipation capacity of the inverter, so that the inverter temperature drops by more than 10 degrees in a short time. The advantage of this method is that it does not require the use of complex and high-cost heat dissipation design, and improves the short-term heat dissipation capacity of the inverter. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The embodiments of the present application may be described more clearly by referring to the accompanying drawings:

[0026] Figure 1 A schematic diagram of a temperature control system provided in an embodiment of the present application;

[0027] Figure 2 (a)- Figure 2 (f) is a curve diagram of the change of various operating parameters in the electric vehicle powertrain relative to the rotor speed;

[0028] Figure 3 A flow diagram of a water cooling circuit 24 and a schematic diagram of the 1.0 state of a valve 242 therein provided in another embodiment of the present application;

[0029] Figure 4 is an internal structure diagram of the valve 242 when it is in state 1.0;

[0030] Figure 5 for Figure 3 A schematic diagram of the valve 242 in the water cooling circuit 24 in the 0.0 state;

[0031] Figure 6 is a schematic diagram of the state control of the valve 242;

[0032] Figure 7 is another state control schematic diagram of the valve 242;

[0033] Figure 8 is another state control schematic diagram of the valve 242;

[0034] Fig. 9 is another state control schematic diagram of the valve 242;

[0035] Fig.10 is another state control schematic diagram of the valve 242;

[0036] Fig.11 is another state control schematic diagram of the valve 242;

[0037] Fig.12 for Figure 1A schematic diagram of the valve 142 in the water cooling circuit 14 in state 1.0 is shown;

[0038] Fig.13 for Figure 1 A schematic diagram of the valve 142 in the water cooling circuit 14 in the 0.0 state;

[0039] Fig.14 is a schematic diagram of a box-shaped bypass layer 141;

[0040] Fig.15 A flow diagram of a water cooling circuit 34 and a schematic diagram of a valve 342 in state 1.0 provided in another embodiment of the present application;

[0041] Fig.16 for Fig.15 A schematic diagram of the valve 342 in the water cooling circuit 34 in the 0.0 state;

[0042] Fig.17 A flow diagram of a water cooling circuit 44 provided in another embodiment of the present application;

[0043] Fig.18 A schematic diagram of a chip 1800 provided in an embodiment of the present application. DETAILED DESCRIPTION

[0044] The technical solutions in the embodiments of the present application will be described below in conjunction with the accompanying drawings.

[0045] Figure 1 A schematic diagram of a temperature control system provided in an embodiment of the present application, wherein the temperature control system is used to dissipate heat from a powertrain of an electric vehicle. The powertrain in an electric vehicle includes Figure 1 The inverter 11, the motor 12 and the motor reducer 13 shown in FIG. Figure 1As shown, the flow path of the temperature control system includes a water cooling circuit 14, an oil cooling circuit 15 and an oil-water heat exchanger 16. The water cooling circuit 14 includes a bypass pipe 141, a valve 142, a water inlet pipe 143 and a water outlet pipe 144 connected to the oil-water heat exchanger 16, a heat absorber 145 for dissipating heat from the inverter 11, a water pump 146, a cooling water tank 147 and a radiator 148. The oil cooling circuit 15 includes: a heat absorber 151 for dissipating heat from the motor reducer 13, a heat absorber 152 for dissipating heat from the motor 12, an oil pump 153 and a cooling oil tank 154. The oil-water heat exchanger 16 includes an absorber 161 connected to the water cooling circuit 14 and a radiator 162 connected to the oil cooling circuit 15, which is used to dissipate heat from the liquid in the oil cooling circuit 15 through the cooling water in the water cooling circuit 14. The bypass pipe 141 is used to be connected in parallel with the heat absorber 161 in the oil-water heat exchanger 16 via the valve 142, so that the flow distribution of water in the water cooling circuit 14 flowing into the bypass pipe 141 and the heat absorber 161 can be controlled by the valve 142 to optimize the heat dissipation capacity of the temperature control system for the powertrain.

[0046] like Figure 1 As shown, in the water cooling circuit 14, the cooling water tank 147 includes cooling water with a relatively low water temperature, and the water pump 146 pumps the water in the cooling water tank so that the water flows into the heat absorber 145 in the direction of the arrow on the right side of the water pump 146 to dissipate heat for the inverter 11. After the water in the water cooling circuit 14 flows through the heat absorber 145, it flows into the heat absorber 161 and / or the bypass pipe 141 under the control of the valve 142, and then flows into the radiator 148. The radiator 148 allows the water to exchange heat with the air, thereby reducing the temperature of the already heated water. Therefore, after passing through the radiator 148, the water in the water cooling circuit 14 flows back to the cooling water tank 147 at a relatively low temperature.

[0047] In the oil cooling circuit 15, the cooling oil tank 154 includes an oily liquid with a relatively low temperature. The oil pump 153 pumps the liquid in the cooling oil tank 154 so that the liquid flows into the heat absorber 152 in the direction of the arrow on the left side of the oil pump 153 to dissipate heat for the motor 12. After that, the liquid in the oil cooling circuit 15 flows into the heat absorber 151 to dissipate heat for the motor reducer 13. After flowing through the heat absorbers 152 and 151, the liquid in the oil cooling circuit 15 flows into the radiator 162 in the heat exchanger 16, thereby exchanging heat with the water flow in the heat absorber 161 in the heat exchanger 16, so that the already heated oil temperature drops. After that, the liquid in the oil cooling circuit 15 flows back to the cooling oil tank 154 at a relatively low temperature after passing through the heat exchanger 16.

[0048] Figure 2 (a)- Figure 2 (f) in the figure is a curve diagram showing the change of each operating parameter in the electric vehicle powertrain relative to the rotor speed. Figure 2As shown in (a) of FIG. 1 , the motor power increases with the increase of the rotor speed in the range of 0 to 6000 revolutions per minute (RPM). The motor power reaches the maximum value at 6000 RPM. After the speed increases to more than 6000 RPM, the motor power remains constant. Figure 2 (b) and Figure 2 As shown in (c) in the figure, the change of motor torque relative to speed is basically the same as the change of stator current relative to speed, which is maintained at a constant maximum value between the rotor speed of 0 and 6000RPM and decreases after the rotor speed exceeds 6000RPM. Figure 2 (d) and Figure 2 (e) in Figure 2 The winding temperature in (d) and Figure 2 The magnetic steel temperatures in (e) correspond to the temperatures of the winding and magnetic steel in the motor, respectively. The changing trends of the winding temperature and magnetic steel temperature relative to the speed basically increase with the increase of the speed. That is, when the rotor speed is higher, the temperature in the motor is also higher, that is, the greater the heating power; the heating power is the heat generated per unit time. If the heat generated by the motor is not dissipated in time, the accumulation of heat will lead to a rise in temperature. Figure 2 In (f), the temperature of the inverter maintains the highest temperature in the range of rotor speed from 0 to about 6000RPM, and starts to decrease after the speed is greater than 6000RPM. Figure 2 (b) Figure 2 (c) and Figure 2 From (f) in the figure, it can be concluded that the inverter temperature is the highest at high torque, high current, and medium and low speeds, that is, the inverter heat generation power is relatively large at this time. At medium and high speeds, the motor temperature is relatively high, that is, the motor heat generation power is relatively large at this time. It can be understood that Figure 2 (a)- Figure 2 The numbers in (f) are schematic. In practice, the corresponding numbers will change according to the different motor parameters and the different input configurations of the motor. Figure 2 (a)- Figure 2 (c) and Figure 2 The curve (f) in FIG. 1 shows the upper limit of the corresponding operating parameter during the driving process of the electric vehicle, which indicates that the value of the corresponding operating parameter can be the value of the curve and the point below the curve, for example, Figure 2As shown in (b) in the figure, during the driving of the electric vehicle, the values ​​of the motor torque and the rotor speed can be the values ​​of any point in the shaded area of ​​the figure. During the user's driving of the electric vehicle, the user changes the current of the motor through his own operation (for example, by stepping on or releasing the accelerator pedal), thereby changing the motor torque, and then changing the speed of the motor to control the electric vehicle. In an electric vehicle, the motor is powered by an inverter, so the current in the motor is changed by adjusting the conversion of the inverter to the current. For example, by allowing the inverter to convert direct current into alternating current with a larger amplitude, the motor current is increased. At the same time, this will increase the heat generation power of the inverter. In other words, the size of the heat generation power of the inverter during operation is related to the Figure 2 The magnitude of the current in (c) or Figure 2 The motor torque in (b) is directly related to the motor current. As the user manipulates the motor torque, it may change suddenly or gradually, from a small torque to a large torque, or from a large torque to a small torque. The heat generated by the inverter also changes with the motor current or the motor torque.

[0049] Therefore, based on the above working process analysis, in the embodiment provided in the present application, when the temperature of the powertrain is controlled, Figure 1The valve 142 in the inverter is controlled to improve the temperature control efficiency of the powertrain. When the inverter heat generation power is large, the valve 142 is in the 1.0 state or an intermediate state close to the 1.0 state. In the 1.0 state, the valve 142 conducts the bypass pipe 141, disconnects (or partially conducts) the connection between the water cooling circuit 14 and the water inlet pipe 143, thereby short-circuiting the oil-water heat exchanger 16 through the bypass pipe 141. When the inverter heat generation power is large, the valve is in the 1.0 state, and the water flow in the water cooling circuit 14 can quickly pass through the bypass pipe 141, which quickly increases the water flow rate in the water cooling circuit 14 and reduces the water temperature, thereby improving the heat dissipation efficiency of the inverter. At the same time, since the motor speed is at a medium-low speed and the heating power is low when the heating power of the inverter is relatively large, the motor can be cooled only by the specific heat of the oil in the oil cooling cycle and the heat capacity of the motor itself. Therefore, in this state, temporarily disconnecting (or partially disconnecting) the water cooling cycle inside the heat exchanger 16 will not cause the motor to be overheated. Risk. Similarly, when the heating power of the inverter is relatively small and the heating power of the motor and the reducer is relatively large, the valve 142 is in a 0.0 state or an intermediate state close to the 0.0 state. In the 0.0 state, the valve 142 disconnects the connection between the water cooling circuit 14 and the bypass pipe 141, and connects the water cooling circuit 14 to the water inlet pipe 143, so that the water in the water cooling circuit 14 enters the oil-water heat exchanger 16, and the cooling water in the water cooling circuit exchanges heat with the liquid in the oil cooling circuit to reduce the temperature of the liquid in the oil cooling circuit, thereby improving the heat dissipation efficiency of the motor and the motor reducer. The intermediate state is a state where both the bypass pipe 141 and the oil-water heat exchanger 16 are partially connected. The intermediate state can be represented by a value in the range of [0.0, 1.0], wherein the larger the intermediate state value is, the closer the bypass pipe 141 is to a fully connected state, i.e., the higher the flow rate ratio of the diverted cooling water is. For example, the intermediate state of 0.8 is a state where the valve 142 is 80% open relative to the opening of the bypass pipe 141, and the intermediate state of 0.2 is a state where the valve 142 is 20% open relative to the opening of the bypass pipe 141.

[0050] It is understandable that although the above reference Figure 1 and Figure 2 However, the above description is only exemplary and not restrictive. Figure 1 The valve 142 is shown as a controllable three-way valve. In the present application, the valve may be a valve in other forms, such as a controllable two-way valve, a mechanical two-way valve, a mechanical three-way valve, etc.

[0051] The temperature control system according to the present application will be described in detail below through specific embodiments.

[0052] Figure 3A flow diagram of a water cooling circuit 24 and a schematic diagram of the 1.0 state of a valve 242 therein are provided for another embodiment of the present application. Figure 3 The water cooling circuit 24 includes Figure 1 The following components are the same as the water cooling circuit 14 in the embodiment: an oil-water heat exchanger 16, a water inlet pipe 143 and a water outlet pipe 144 connected to the oil-water heat exchanger 16, a bypass pipe 141, a heat absorber 145 for dissipating heat from the inverter 11, a water pump 146, a cooling water tank 147 and a radiator 148.

[0053] Figure 3 The water cooling circuit 24 in Figure 1 The difference between the water cooling circuit 14 in the embodiment is that the water cooling circuit 24 includes a valve 242, which includes two water inlets, port A and port B, and a water outlet port P, wherein port A is connected to the bypass pipe 141, port B is connected to the water outlet pipe 144, and port P is connected to a section of the main pipe in the water cooling circuit 24. One end of the bypass pipe 141 located at "C" in the figure is connected to the water inlet pipe 143 and the main pipe of the water cooling circuit 24, and the other end is connected to port A of the valve 242, thereby being connected in parallel with the oil-water heat exchanger 16.

[0054] Figure 3 The 1.0 state of valve 242 is shown in FIG. Figure 4 2 is the internal structure diagram of the valve 242 when it is in the 1.0 state. Figure 4 As shown, the valve 242 includes a piston 41 and a piston 42 that are linked together. Figure 4 In the 1.0 state shown in FIG. 1 , the positions of pistons 41 and 42 are such that port A is opened and port B is closed. Figure 3 As shown by the solid arrow on the upper part of the bypass pipe 141, the valve 242 connects the bypass pipe 141 to the main pipe of the water cooling circuit 24, and at the same time, the valve 242 disconnects the water outlet pipe 144 from the main pipe of the water cooling circuit 24, so that Figure 3 As shown by the “×”, when the water flow in the water cooling circuit flows through point C, all of it passes through the bypass pipe 141 and does not flow into the oil-water heat exchanger 16.

[0055] Figure 5 for Figure 3 Schematic diagram of the 0.0 state of the valve 242 in the water cooling circuit 24. Figure 5 As shown, in the 0.0 state of valve 242, as Figure 4 As shown by the arrow in FIG. 1 , the valve 242 connects the outlet pipe 144 to the main pipe of the water cooling circuit 24. Figure 5 As shown by × in the figure, the valve 242 disconnects the bypass pipe 141 from the main pipe of the water cooling circuit 24, so that the water flow in the water cooling circuit flows into the oil-water heat exchanger 16 when passing through point C, and does not flow into the bypass pipe 141.

[0056] Figure 3 and Figure 5 The valve 242 shown in the figure can be a controllable valve, such as a solenoid valve, an electric valve, a hydraulic valve, etc., or the valve 242 can also be an uncontrollable valve, such as a mechanical valve. In the case where the valve 242 is an uncontrollable valve, the mechanical valve is pre-set so that the state of the valve is constantly maintained at an intermediate state between 0.0 and 0.1, that is, by pre-setting the mechanical valve as shown in the figure, the valve 242 can be controlled by the control valve 242, such as a solenoid valve, an electric valve, a hydraulic valve, etc., or the valve 242 can be controlled by the control valve 242, such as a mechanical valve. Figure 4 The valve shown makes both port A and port B partially open, so that the water flows to the bypass pipe 141 and the oil-water heat exchanger 16 respectively after passing through point C, thereby reducing the flow resistance of the entire water cooling circuit through the bypass pipe 141, increasing the flow rate of the water cooling circuit, and improving the heat dissipation efficiency of the inverter 11.

[0057] In the case where valve 242 is a controllable valve, the state of valve 242 can be controlled so that: during the process of increasing the heating power of the inverter 11 or before the heating power of the inverter 11 increases, the flow percentage of the cooling water flow in the water cooling circuit 24 flowing into the bypass pipe 141 is increased and the flow percentage of the cooling water flow flowing into the oil-water heat exchanger 16 is reduced; after the heating power of the inverter decreases, the flow percentage of the cooling water flow flowing into the bypass pipe 141 is reduced, and the flow percentage of the cooling water flow flowing into the oil-water heat exchanger 16 is increased, thereby further optimizing the heat dissipation efficiency of the temperature control system for the powertrain.

[0058] In the case where the valve 242 is an electromagnetic valve, for example, the initial state of the valve 242 is Figure 4 The 1.0 state shown in the figure, that is, port A is open and port B is closed. When the coil (not shown) on the linkage piston is energized to apply an electromagnetic force to the linkage piston to push the piston to the right, the linkage piston moves quickly to the right until the piston 42 reaches the rightmost side, so that port A is closed and port B is opened, that is, the valve 242 is in the 0.0 state. When the power supply to the coil is disconnected, the linkage piston returns to the Figure 4 Since the electromagnetic valve can only be in two states, 1.0 and 0.0, in the case where the valve 242 is an electromagnetic valve, the valve 242 does not have the above-mentioned intermediate state.

[0059] In the case where the valve 242 is an electric valve, such as Figure 4As shown, in valve 242, the linkage piston can be moved left and right at a predetermined speed, and the movement of the linkage piston can be stopped at any position during the movement and the linkage piston can be kept at this position. Therefore, in the case where valve 242 is an electric valve, the initial position of the linkage piston can be any position in its left and right movement space, and the position of the linkage piston in the valve can be changed by controlling the valve. For example, the linkage piston can be stopped at the middle position inside the valve so that both port A and port B are partially open. In the case where valve 242 is an electric valve, similar to the above-mentioned electromagnetic valve, Figure 4 The valve state shown is the 1.0 state, the state where the piston 42 is located at the far right is the 0.0 state, and in addition, the position where the linkage piston is located in the middle of the valve 242 so that both the A port and the B port are partially opened is the above-mentioned intermediate state.

[0060] Figure 6 This is a schematic diagram of the state control of the valve 242. The above-mentioned electromagnetic three-way valve or electric three-way valve can be used to achieve Figure 6 Status control shown. Figure 6 The control shown includes control relative to operating conditions I and II. Figure 6 As shown in the figure, operating condition I includes every point located in the surface marked with "I" in the figure, and operating condition II includes every point located in the surface marked with "II" in the figure. In operating condition I, the motor torque is greater than or equal to T1, combined with the above Figure 2 (b) Figure 2 (d) Figure 2 (e) and Figure 2 It can be seen from (f) in that for each torque value in the working condition I, the heating power of the inverter is greater than or equal to the predetermined threshold, while the heating power of the motor is smaller. Therefore, in the working condition I, by controlling the valve 242 to be in the 1.0 state, the cooling water only flows into the bypass pipe 141. Since the water resistance of the bypass pipe 141 is small, the water flow rate in the water cooling circuit is increased, and the heat dissipation efficiency of the inverter is improved.

[0061] In working condition II, if Figure 6 As shown in , the motor torque is less than T1. Figure 2 (b) Figure 2 (d) Figure 2 (e) and Figure 2As can be seen from (f) in the figure, the heating power of the inverter is less than the predetermined threshold value, while the heating power of the motor is larger when the speed is higher, that is, in some cases in working condition II, the heating power of the motor is larger. Therefore, in working condition II, by controlling valve 242 to be in the 0.0 state, the cooling water flow all flows into the oil-water heat exchanger 16 instead of flowing into the bypass pipe 141, so that the cooling water flow in the water cooling circuit 24 dissipates the heat of the oil cooling circuit 15, thereby improving the heat dissipation capacity of the motor. It can be understood that T1 marked in the figure is only schematic, and the size of T1 can be set according to the needs of the specific vehicle, so it is not necessarily located at the position shown in the figure. Reference Figure 2 (a)- Figure 2 In (f), since the changes of various working parameters in the powertrain are related, in the present application, it is not limited to dividing the working conditions and determining the control of the valve based on the predetermined torque value. For example, the working conditions can also be divided based on the predetermined values ​​of any one or several of the following items: motor power, motor stator current, motor rotor speed, motor heating power, motor winding temperature, motor magnetic steel temperature, inverter temperature, inverter heating power, etc. The above-mentioned parameter values ​​can be directly measured by the sensor unit of the electric vehicle and then transmitted to the controller of the electric vehicle, or can be determined by the controller based on the input calculation from the sensor unit, so that the controller can control the valve 242 based on the value of any parameter or the values ​​of several parameters. For example, refer to Figure 2 (d) in the figure can be used to divide the operating conditions based on the values ​​of both winding temperature and rotor speed and to determine the control of the valve.

[0062] As described above, when a user drives an electric vehicle, the heating power of the inverter may change based on the user's manipulation. For example, after the user accelerates by stepping on the accelerator pedal, the controller in the electric vehicle first determines the change in the torque of the motor based on the user's stepping depth sensed and input by the sensor, so as to determine the change in the heating power of the inverter. For example, based on the user's stepping depth on the accelerator pedal, it can be determined that the motor torque will change from Figure 6T3 in the figure changes to T2. Since T2 is in the range of working condition I and T3 is in the range of working condition II, the motor torque will increase, that is, the heating power of the inverter will increase. Therefore, the controller can change the state of valve 242 from 0.0 to 1.0 before or while increasing the motor torque (that is, during the process of increasing the motor torque, the process takes a short time and can be regarded as simultaneous) to adapt to the increase in the heating power of the inverter caused by the user's control action, so that the temperature of the inverter can be reduced by more than 10 degrees in a short time. After the state of valve 242 is controlled to be state 1.0, the motor speed increases due to the increase in motor current, thereby increasing the heat generation power of the motor, and there may be a risk of overheating. Therefore, after a predetermined period of time (for example, tens of seconds) after the state of valve 242 is changed to state 1.0, it is necessary to actively reduce the motor current in the electric vehicle and reduce the motor torque, so that the operating condition of the powertrain is changed to operating condition II again. After reducing the motor torque, the heat generation power of the inverter is reduced, and the inverter is no longer at risk of overheating, so that the controller can restore the state of valve 242 to state 0.0.

[0063] In the case where the controller in the electric vehicle determines that the motor torque will change from working condition I to working condition II based on the user's manipulation, the controller first reduces the motor torque so that the working condition of the electric vehicle powertrain changes from working condition I to working condition II accordingly. Since the heat generation power of the inverter is reduced after the motor torque is reduced, there is no risk of overheating, so the controller can change the valve state from 1.0 state to 0.0 state after reducing the motor torque.

[0064] Figure 7 FIG. 2 is another state control schematic diagram of the valve 242 . Figure 7 The control shown includes the control relative to working condition I to working condition III. In working condition I, the motor torque is greater than or equal to T1, and the same reference Figure 2 In (f), the inverter heating power is high. In this case, the controller controls valve 242 to make its state 1.0, thereby improving the heat dissipation efficiency of the inverter. In condition II, the motor torque is less than T1 and greater than or equal to T2. The inverter heating power is reduced compared to the heating power of condition I. Therefore, the controller controls valve 242 to make its state 0.6, that is, reference Figure 4 , so that port A is opened by about 60%, that is, port B is opened by about 40%, so that about 60% of the fluid flow in the cooling circuit 24 flows into the bypass pipe 141, and about 40% of the fluid flow flows into the oil-water heat exchanger 16. In working condition III, the motor torque is less than T2, and the heat generation power of the inverter is small. In the part with a larger speed in working condition III, the heat generation power of the motor is high, which is Figure 6Similarly, the controller controls the valve 242 to be in state 0.0, thereby increasing the water flow in the water cooling circuit 24 flowing into the oil-water heat exchanger 16 to improve the heat dissipation capacity of the motor.

[0065] Based on the above Figure 6 Similarly, the controller in the electric vehicle first determines the change that will occur in the torque of the motor based on the user's operation, so as to determine the change that will occur in the heating power of the inverter. In the case where the controller determines that the torque will be increased, the state of the valve 242 may be changed before or while the motor torque is increased, and in the case where the torque is determined to be reduced, the state of the valve 242 may be changed after the motor torque is reduced. For example, in the case where the controller determines that the torque will be changed from working condition III to working condition I, the state of the valve 242 is changed from 0.0 to 1.0 before or at the same time as the change; in the case where the controller determines that the torque will be changed from working condition III to working condition II, the state of the valve 242 is changed from 0.0 to 0.6 before or at the same time as the change; in the case where the controller determines that the torque will be changed from working condition II to working condition I, the state of the valve 242 is changed from 0.6 to 1.0 before or at the same time as the change. When the controller determines that the torque is going to change from condition I to condition II, after the change is made, the state of valve 242 is changed from 1.0 to 0.6. When the controller determines that the torque is going to change from condition I to condition III, after the change is made, the state of valve 242 is changed from 1.0 to 0.0. When the controller determines that the torque is going to change from condition II to condition III, after the change is made, the state of valve 242 is changed from 0.6 to 0.0.

[0066] Figure 8 FIG. 2 is another state control schematic diagram of the valve 242 . Figure 8 The control shown includes control relative to operating conditions I to IV. Figure 8 Relative to Figure 7 The difference of the control is that between the working condition I corresponding to the valve state 1.0 and the working condition IV corresponding to the valve state 0.0, there are two working conditions, working conditions II and working conditions III, corresponding to the two intermediate states of the valve (0.6 and 0.2). Figure 8As shown in, in working condition II, the motor torque is between T1 and T2, and the heating power of the inverter is not much lower than that of working condition I. The controller controls valve 242 so that valve 242 is in the 0.6 state, that is, about 60% of the water flow in the cooling circuit 24 flows into the bypass pipe 16, so that the heat dissipation efficiency of the inverter is higher. In working condition III, the motor torque is between T2 and T3, and the heating power of the inverter is much lower than that of working condition I. The controller controls valve 242 so that valve 242 is in the 0.2 state to reduce the heat dissipation of the inverter and increase the heat dissipation of the motor. Therefore, the controller can perform more precise valve control relative to the change of the heating power of the inverter. The specific control process of the controller on valve 242 when the working condition of the powertrain changes is the same as that based on the above. Figure 6 and Figure 7 The control process is similar and will not be described here.

[0067] Fig. 9 FIG. 2 is another state control schematic diagram of the valve 242 . Fig. 9 The control shown does not divide the working conditions, but makes the state of valve 242 change from 0.0 state to 1.0 state on average as the motor torque increases from small to large, that is, makes the state value of valve 242 proportional to the magnitude of the motor torque. Therefore, when the controller in the electric vehicle determines that the torque of the motor is about to change, it can determine the state value of valve 242 according to the value that the motor torque is about to reach, and control the state of valve 242 accordingly. Specifically, when the controller determines that the motor torque is about to increase, the value that the motor torque is about to reach after the increase is first determined, and then the state of valve 242 is determined based on the torque value to be reached, and then, before or at the same time as the motor torque is increased, the state of valve 242 is changed to the above-determined state. When the controller determines that the motor torque is about to decrease, the motor torque is first reduced, and then the state of valve 242 is determined based on the value after the motor torque is reduced, and the state of valve 242 is changed to the determined state.

[0068] exist Figure 6-Figure 9 In the state control schematic diagram shown in FIG. 1 , when the inverter heating power is large, the valve is in the 1.0 state, and when the inverter heating power is small, the valve is in the 0.0 state. The embodiment of the present application is not limited thereto. For example, in the case where the valve 242 is a controllable electric valve, the valve 242 can also be controlled by, for example, Figure 10-11 The state control schematic diagram is used to control valve 242.

[0069] Fig.10 FIG. 2 is another state control schematic diagram of the valve 242 . Fig.10The control shown includes valve control corresponding to working condition I and working condition II. In working condition I, the heating power of the inverter is greater than or equal to the predetermined value, while the heating power of the motor is relatively small. In this working condition I, the controller controls the valve 242 to be in the 0.8 state, so that about 80% of the flow of the cooling water flow flows into the bypass pipe 141, so that the flow rate of the cooling water flow increases, and the heat dissipation efficiency of the inverter is improved. At the same time, about 20% of the flow of the cooling water flow is maintained to flow into the heat exchanger 16 for heat exchange of the coolant in the oil cooling circuit. In working condition II, the motor torque is less than T1, and the heating power of the inverter is less than the predetermined value. In the part of working condition II where the speed is larger, the heating power of the motor is higher, so the valve 242 is controlled to be in the state 0.3, that is, about 70% of the flow of the cooling water flow flows into the oil-water heat exchanger 16, and about 30% of the flow flows into the bypass pipe 141, thereby improving the heat dissipation capacity of the motor.

[0070] Fig.11 FIG. 2 is another state control schematic diagram of the valve 242 . Fig.11 The control shown includes valve control corresponding to working conditions I to working conditions III. In working condition I, the motor torque is greater than or equal to T1, and the heating power of the inverter is relatively large. In this case, the controller controls valve 242 so that the state of valve 242 is 0.8, that is, about 80% of the flow of cooling water flows into the bypass pipe 141. In working condition II, the motor torque is between T1 and T2. At this time, the heating power of the inverter decreases. The valve 242 is controlled to be in a state of 0.6, so that about 60% of the flow of cooling water flows into the bypass pipe 141. In working condition III, the motor torque is less than T2, and the valve 242 is controlled to be in a state of 0.3, thereby further reducing the flow percentage in the bypass pipe 141 and improving the heat dissipation capacity of the motor.

[0071] The controller is based on the change of the powertrain operating conditions. Fig.10 and Fig.11 The control process of valve 242 can be referred to above for Figure 6 and Figure 7 The description will not be repeated here.

[0072] Fig.12 for Figure 1 The 1.0 state schematic diagram of the valve 142 in the water cooling circuit 14 is shown. The difference between the valve 142 and the valve 242 is that the valve 142 includes a water inlet (port P) and two water outlets (port A and port B). Fig.12 The valve 142 may also have a main pipe connected to the water cooling circuit 14 in the embodiment of the present invention, and the port A and the port B are connected to the bypass pipe 141 and the water inlet pipe 143 of the oil-water heat exchanger 16 respectively. Figure 4 The internal structure shown is Figure 3 The valve 242 in FIG. 1 is different in that, in this embodiment, Figure 4 The P port in the figure is the water inlet of the valve 142. Figure 4 Port A and port B are two water outlets of valve 142.

[0073] In the 1.0 state of valve 142, such as Fig.12 As shown by the arrow in FIG. 1 , the valve 142 connects the bypass pipe 141 to the main pipe of the water cooling circuit 14. Fig.12 As shown by the mark “×” in the figure, the valve 142 disconnects the main line of the water cooling circuit 14 from the water inlet pipe 143, so that the water in the water cooling circuit flows into the bypass pipe 141 when passing through the valve 142, and does not flow into the oil-water heat exchanger 16. The water flowing into the bypass pipe 141 flows into the main line of the water cooling circuit 14 through point C in the figure, that is, when the valve 142 is in the 1.0 state, the bypass pipe 141 short-circuits the oil-water heat exchanger.

[0074] Fig.13 for Figure 1 Schematic diagram of the 0.0 state of the valve 142 in the water cooling circuit 14. In the 0.0 state of the valve 142, as shown in FIG. Fig.13 As shown by the arrow in FIG. 1 , the valve 142 connects the water inlet pipe 143 to the main pipe of the water cooling circuit 14. Fig.13 As shown by the mark “×” in the figure, the valve 142 disconnects the bypass pipe 141 from the main pipe of the water cooling circuit 14, so that the water flow in the water cooling circuit 14 flows into the oil-water heat exchanger 16 when flowing through the valve 142, and does not flow into the bypass pipe 141.

[0075] In this embodiment, Figure 3 Similar to the embodiment shown, valve 142 can be a controllable valve or an uncontrollable valve. In the case where valve 142 is a controllable valve, the controller can be based on Figure 6-Figure 11 Any one of them controls the state of the valve 142 to optimize the heat dissipation efficiency of the powertrain, which will not be repeated here.

[0076] It can be understood that although in the above embodiments, the component for short-circuiting the oil-water heat exchanger 16 is described and shown as the bypass pipe 141, in practice, the component is not limited to being made into a tubular component, but can be made into a component of any shape as needed. Fig.14 Schematic diagram of the box-shaped bypass layer 141. Fig.14 As shown in FIG. 1 , the box-shaped bypass layer 141 is made to be adapted to the shape of the oil-water heat exchanger 16 so that it can be stacked on the upper part of the oil-water heat exchanger 16. The bypass layer 141 includes a hollow inner cavity, and a three-way valve 142 is installed in the inner cavity to communicate with the bypass layer 141. Fig.12Correspondingly, the three-way valve 142 includes a P port as a water inlet and an A port and a B port as water outlets, wherein the P port is connected to the main pipe of the water cooling circuit 14, the water outlet A is arranged to face the inner cavity of the bypass layer 141, and the water outlet B is connected to the water inlet pipe 143 of the oil-water heat exchanger 16. In addition, the inner cavity of the bypass layer 141 is also connected to the water outlet pipe 144 of the oil-water heat exchanger 16, and is connected to the main pipe of the water cooling circuit 14 at C. In the bypass layer 141, when the valve 142 is in the 1.0 state, that is, the A port is opened and the B port is closed, so that the water flowing from the main line of the water cooling circuit 14 through the P port into the valve 142 enters the inner cavity of the bypass layer 141 from the A port, and flows back to the main line of the water cooling circuit 14 through the C. When the valve 142 is in the 0.0 state, that is, the B port is opened and the A port is closed, so that the water flowing from the main line of the water cooling circuit 14 through the P port into the valve 142 enters the oil-water heat exchanger 16 from the water inlet pipe 143, and flows into the inner cavity of the bypass layer 141 from the water outlet pipe 144 of the oil-water heat exchanger 16, and flows back to the main line of the water cooling circuit 14 from the C. In other words, the bypass layer 141 can play the same effect as the bypass pipe 141.

[0077] Fig.15 FIG. 1 is a flow diagram of a water cooling circuit 34 and a schematic diagram of a valve 342 in a state 1.0 provided in another embodiment of the present application. Figure 3 Similar to the embodiment shown, the water cooling circuit 34 also includes a bypass pipe 141, an oil-water heat exchanger 16, a water inlet pipe 143 and a water outlet pipe 144 of the oil-water heat exchanger 16, a heat absorber 145, a water pump 146, a cooling water tank 147 and a radiator 148, and Figure 3 The embodiment shown is different in that the valve 342 in this embodiment is a two-way valve, which is arranged in the bypass pipe 141 and is used to control the connection and disconnection between the bypass pipe 141 and the main pipe of the water cooling circuit 34. Similar to the previous embodiment, the bypass pipe 141 is connected in parallel with the oil-water heat exchanger 16.

[0078] like Fig.15 As shown, in the 1.0 state of the valve 342, as shown by the solid arrow in the figure, the valve 342 conducts the communication between the bypass pipe 141 and the main pipe of the water cooling circuit 34. Fig.15 As shown by the dashed arrow in FIG. 1 , in the 1.0 state of the valve 342, the valve 342 cannot cut off the flow of water in the main line of the water cooling circuit 34 toward the oil-water heat exchanger 16. When the water in the main line of the water cooling circuit 34 reaches Fig.15Whether a part of the water flow is separated and flows to the oil-water heat exchanger 16 at the intersection point C in the water cooling circuit 34 depends on the flow resistance of the bypass pipe 141. If the bypass pipe 141 is set to be thicker and the flow resistance is very small, the water flow flowing to the oil-water heat exchanger 16 will be approximately zero. If the bypass pipe 141 is set to be thinner and the flow resistance is larger, the water flow at point C flows toward the bypass pipe 142 and the oil-water heat exchanger 16 respectively, that is, at point C in the water cooling circuit 34, the water flow is distributed to the two branches of the oil-water heat exchanger 16 and the bypass pipe 142 in a certain proportion through the control of the valve 143.

[0079] Fig.16 for Fig.15 Schematic diagram of the 0.0 state of the valve 342 in the water cooling circuit 34 shown in FIG. Fig.16 As shown, in the 0.0 state of the valve 342, as indicated by the mark “×” in the figure, the valve 342 disconnects the main line of the water cooling circuit 34 from the bypass pipe 141, so that the water flow in the water cooling circuit 34 flows through Fig.16 At point C in the diagram, all of the water flows into the oil-water heat exchanger 16 and does not flow into the bypass pipe 141.

[0080] In this embodiment, Figure 3 Similar to the embodiment shown, valve 342 can be a controllable valve or an uncontrollable valve. In the case where valve 342 is a controllable valve, the controller can be based on the above description similarly. Figure 6-Figure 11 Any of the above can be used to control the state of the valve 342, thereby optimizing the heat dissipation capacity of the powertrain, which will not be described in detail here. In this embodiment, the intermediate state of the valve 342 is the state in which the valve 342 is partially open relative to the opening of the bypass pipe 142, wherein the intermediate state close to 1.0 is the state in which the opening of the valve 342 is more open, and the intermediate state close to 0.0 is the state in which the opening of the valve 342 is less open. For example, the state 0.8 can be the state in which the valve 342 is about 80% open relative to the opening of the bypass pipe 142, and the state 0.2 can be the state in which the valve 342 is about 20% open relative to the opening of the bypass pipe 142.

[0081] Fig.17 FIG. 4 is a flow diagram of a water cooling circuit 44 provided in another embodiment of the present application. Fig.17As shown in , the water cooling circuit includes an oil-water heat exchanger 16, a water inlet pipe 143 and a water outlet pipe 144 connected to the oil-water heat exchanger 16, a bypass pipe 141, a heat absorber 145, a water pump 146, a cooling water tank 147 and a radiator 148, wherein the bypass pipe 141 is connected in parallel with the oil-water heat exchanger 16. Different from the previous embodiment, the embodiment does not include a valve for controlling the flow direction of water flow. By making the bypass pipe 141 have a predetermined flow resistance, when the water flow in the main line of the water cooling circuit 44 flows to the intersection C, the bypass pipe 141 and the oil-water heat exchanger 16 are diverted at a certain flow ratio, thereby reducing the flow resistance of the water cooling circuit 44 and increasing the water flow velocity in the water cooling circuit 44 compared to the circuit without the bypass pipe 141, thereby improving the heat dissipation efficiency of the inverter 11, and at the same time, it will not affect the heat dissipation of the motor. In this embodiment, since the flow resistance of the bypass pipe 141 is constant, the water flow in the water cooling circuit 44 is always split at the same flow ratio when it flows to the intersection C. In addition, since no valve is required in this embodiment, the manufacturing cost is low.

[0082] Fig.18 A schematic diagram of a chip 1800 provided in an embodiment of the present application includes: an interface circuit 181, a memory 182 and a processor 183,

[0083] The interface circuit 181 is coupled to the processor 183;

[0084] The memory 182 stores a computer program or instruction, and the processor 183 is used to run the computer program or instruction to implement the above-mentioned Figure 6-Figure 11 The control process of the valve in the above temperature control system is to perform temperature control based on the above temperature control system.

[0085] The chip 1800 is, for example, a chip included in a controller in the electric vehicle mentioned above.

[0086] The interface circuit 181 is used to receive sensed values ​​from sensors in the electric vehicle to obtain operating parameter values, such as torque value, current value, etc. The operating parameter values ​​are used as input parameters when running the computer program or instruction.

[0087] The memory 182 may be a volatile memory, such as a random-access memory (RAM); the memory 112 may be a non-volatile memory, such as a read-only memory (ROM), a flash memory, a hard disk drive (HDD) or a solid-state drive (SSD); the memory 112 may also include a combination of the above-mentioned types of memories.

[0088] The present application also discloses a vehicle, which includes a water cooling circuit according to any of the above embodiments in its temperature control system for the powertrain, so as to have a better heat dissipation effect than the prior art. It can be understood that in the above, although the temperature control system according to the embodiment of the present application is described by taking an electric vehicle as an example, the temperature control system according to the present application is not limited to electric vehicles, but can also be used for other vehicles, such as hybrid vehicles and the like. In addition, in the above description, although it is described that the temperature control system according to the present application includes a water cooling circuit and an oil cooling circuit, the embodiment of the present application is not limited to this. In the temperature control system according to the present application, a first cooling circuit and a second cooling circuit may be included, and the first cooling medium in the first cooling circuit and the second cooling medium in the second cooling circuit may be determined according to the actual needs of the vehicle, and there is no limitation on this.

[0089] Those of ordinary skill in the art should further appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described in terms of function in the above description. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the present invention.

[0090] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A vehicle, characterized in that: The vehicle includes an inverter, a motor, a heat exchanger, a first cooling circuit, and a second cooling circuit, wherein the inverter is used to supply power to the motor, heat of the inverter is absorbed by a first cooling medium of the first cooling circuit, heat of the motor is absorbed by a second cooling medium of the second cooling circuit, the first cooling medium of the first cooling circuit dissipates heat through the first radiator, and the first cooling medium of the first cooling circuit performs heat exchange with the second cooling medium of the second cooling circuit through the heat exchanger, wherein: The vehicle further includes a controllable valve and a bypass branch, wherein the bypass branch is connected in parallel with the heat exchanger, and the controllable valve controls the flow distribution of the first cooling medium to the heat exchanger and the bypass branch.

2. The vehicle according to claim 1, characterized in that The bypass branch includes a bypass layer, and the bypass layer and the heat exchanger are stacked.

3. The vehicle according to claim 2, characterized in that The bypass layer includes a hollow inner cavity, and the valve is arranged in the inner cavity.

4. The vehicle according to any one of claims 1 to 3, characterized in that: The heat exchanger includes a heat absorber and a second radiator. The heat absorber is in communication with the first cooling circuit, and the second radiator is in communication with the second cooling circuit.

5. The vehicle according to any one of claims 1 to 4, characterized in that: The controllable valve is a two-way valve, and the two-way valve is arranged in the bypass branch.

6. The vehicle according to any one of claims 1 to 5, characterized in that: The controllable valve is a three-way valve, two interfaces of the three-way valve are connected to the first cooling flow channel, and the third interface of the three-way valve is connected to the bypass branch.

7. The vehicle according to any one of claims 1 to 6, characterized in that: The first cooling medium is cooling water. The first cooling circuit further includes a water tank and a water pump. The water pump is used to pump out the cooling water in the water tank. The water tank is used to receive the cooling water flowing out of the first radiator.

8. The vehicle according to any one of claims 1 to 7, characterized in that: The second cooling medium is an oily liquid and the oil pump is used to pump the oily liquid out of the oil tank.

9. The vehicle according to any one of claims 1 to 8, characterized in that: The vehicle further includes a reducer, and the second cooling medium in the second cooling circuit flows through the motor and the reducer in sequence.

10. The vehicle according to any one of claims 1 to 9, characterized in that The controllable valve is used to control the flow distribution of the first cooling medium to the heat exchanger and the bypass branch according to any one or more of the motor speed, motor power, motor heating power, motor stator current, inverter temperature, inverter heating power, and motor temperature.

11. The vehicle according to any one of claims 1 to 10, characterized in that The controllable valve is controlled as follows: When the heat generation power of the inverter increases or when the heat generation power of the inverter is about to increase, the flow percentage of the first cooling medium flowing to the bypass branch is increased.

12. The vehicle according to any one of claims 1 to 10, characterized in that The controllable valve is controlled as follows: After the heat generation power of the inverter is reduced, the flow percentage of the first cooling medium flowing to the bypass branch is reduced.

13. The vehicle according to any one of claims 1 to 11, characterized in that The controllable valve is controlled as follows: When the electric vehicle is about to reach a first predetermined operating condition, wherein the first operating condition is that the torque of the motor reaches a first set threshold, the flow percentage of the first cooling medium flowing to the bypass branch is increased to a first percentage.

14. The vehicle according to claim 12, characterized in that The valve is controlled as follows: when the electric vehicle is about to reach a second predetermined operating condition, the second operating condition is that the torque of the motor reaches a second set threshold, the flow percentage of the first cooling medium flowing to the bypass branch is increased to a second percentage, wherein the heating power of the inverter corresponding to the first predetermined operating condition is greater than the heating power of the inverter corresponding to the second predetermined operating condition, and the first percentage is greater than the second percentage.

15. The vehicle according to claim 13 or 14, characterized in that The valve is controlled to reduce the flow percentage of the first cooling medium flowing to the bypass branch to a third percentage after the electric vehicle reaches a third predetermined operating condition, where the third operating condition is that the torque of the motor reaches a third set threshold.

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