Method, apparatus and vehicle for cooling a stalled drive motor of a vehicle

Abstract

A method for cooling a stalled traction motor of a vehicle, the vehicle (500) comprising a traction motor (501), an engine (502), an engine-end oil pump (503), and a cooling channel (504), the engine (502) is used to drive the operation of the engine-end oil pump (503), the cooling channel (504) connecting the engine-end oil pump (503) and the traction motor (501), the method comprising: when a driving mode of the vehicle (500) is in a pure electric mode, the vehicle (500) satisfies a predetermined motor stall operating condition, and a current temperature of the traction motor (501) is greater than an engine assisted cooling start-up temperature, controlling the start-up of the engine (502) of the vehicle (500), and the engine-end oil pump (503) of the vehicle (500) drives a coolant fluid in the cooling channel (504) to cool the traction motor (501).

Description

[Technical field]

[0001] The present disclosure relates to the field of vehicle heat dissipation, and more particularly to a method, apparatus, and vehicle for cooling a stalled drive motor of a vehicle. [Background technology]

[0002] For hybrid vehicles equipped with an electric oil pump, the cooling system can be driven by the electric oil pump to cool the drive motor under all driving conditions. However, for hybrid vehicles not equipped with an electric oil pump, in the pure electric mode, the cooling of the drive motor mainly relies on the rotation of the wheels to drive the wheel-end oil pump to perform the cooling work. However, when the hybrid vehicle is in the pure electric mode, if the drive motor stalls, the vehicle speed will slow down and the wheel-end oil pump will be low, which will not be able to supply enough coolant liquid to cool the drive motor, resulting in a shortened lifespan of the drive motor or even burnout. Summary of the Invention [Problem to be solved by the invention]

[0003] The present disclosure aims to provide a method, an apparatus and a vehicle for cooling a stalled drive motor of a vehicle, which are applied to a drive motor and solve the technical problem of being unable to provide sufficient coolant liquid to cool the drive motor due to stalling of the drive motor in pure electric mode. [Means for solving the problem]

[0004] In order to achieve the above object, a first aspect of the present disclosure provides a method for cooling a stalled drive motor of a vehicle, the vehicle comprising: a drive motor, an engine, an engine-end oil pump, and a cooling passage, the engine being used to drive operation of the engine-end oil pump, the cooling passage connecting the engine-end oil pump and the drive motor, the method comprising: When the driving mode of the vehicle is in a pure electric mode, and the vehicle satisfies a predetermined motor stall operating condition, and the current temperature of the driving motor is greater than an engine assisted cooling start-up temperature, controlling and starting the engine of the vehicle, so that the engine-end oil pump of the vehicle drives the coolant liquid in the cooling passage to cool the driving motor.

[0005] Optionally, the method further comprises: determining a first time length for the temperature of the driving motor to reach a first predetermined temperature based on a temperature change rate of the driving motor and a current temperature of the driving motor; If the first length of time is less than or equal to a first predetermined length of time, decreasing the engine assist cooling start-up temperature.

[0006] Optionally, decreasing the engine assisted cooling start temperature if the first length of time is less than or equal to a first predetermined length of time includes: If the first time length is equal to or shorter than a first predetermined time length, determining a target correction offset amount based on a temperature change rate of the driving motor and a predetermined relationship between the temperature change rate and a correction offset amount; The difference between the first predetermined temperature and the target correction offset amount is set as the engine assist cooling start temperature.

[0007] Optionally, decreasing the engine assisted cooling start temperature if the first length of time is less than or equal to a first predetermined length of time includes: If the first length of time is less than or equal to a first predetermined length of time, the engine assisted cooling start temperature is equal to a second predetermined temperature, the second predetermined temperature being less than the first predetermined temperature.

[0008] Optionally, the method further comprises: The method further includes, if the first length of time is greater than a first predetermined length of time, then the engine assisted cooling start temperature is equal to the first predetermined temperature.

[0009] Optionally, the method further comprises: and controlling the engine to stop operating after a second predetermined length of time if the vehicle satisfies a predetermined motor stall exit condition and the current temperature of the traction motor is determined to be less than an engine assist cooling stop temperature.

[0010] Optionally, the first predetermined temperature is a maximum allowable temperature of the drive motor, the second predetermined temperature is a safe start-up temperature when the drive motor is in a stalled condition, and the engine assisted cool start-up temperature is less than or equal to the first predetermined temperature.

[0011] Optionally, the method further comprises: Controlling the rotation speed of the engine based on the current temperature of the traction motor, where there is a positive correlation between the rotation speed of the engine and the current temperature of the traction motor; The method further includes, when the vehicle satisfies a predetermined motor stall operating condition and the flow rate of the cooling passage flowing through the drive motor is greater than a first predetermined cooling flow rate, controlling a heat dissipation fan of the vehicle to operate at a maximum rotational speed, thereby cooling the drive motor.

[0012] Optionally, the method further comprises: When the vehicle satisfies a predetermined motor stall termination condition and a flow rate of the cooling flow passage through the traction motor is less than a second predetermined cooling flow rate, the method further includes controlling the heat dissipation fan to operate; Here, the first predetermined cooling flow rate is greater than the second predetermined cooling flow rate.

[0013] Optionally, controlling engine start of the vehicle further comprises: Controlling the engine to output a predetermined rotation speed; and controlling a heat dissipation fan of the vehicle to operate at a maximum rotation speed to cool the drive motor.

[0014] Optionally, the method further comprises: determining that the vehicle meets a predetermined motor stall exit condition and that a current temperature of the traction motor is less than an engine assist cooling stop temperature; The method further includes controlling the heat dissipation fan to operate and, after a second predetermined time period, controlling the engine to stop operating, or controlling the engine and the heat dissipation fan to stop operating, after a second predetermined time period.

[0015] Optionally, the predetermined motor stall operating condition includes that the range of the vehicle is in a forward range or a reverse range, that the torque of the drive motor is equal to or greater than a first predetermined torque, and that the vehicle speed is equal to or less than a first predetermined vehicle speed; the predetermined motor stall termination conditions include: a range of the vehicle is not a forward range or a reverse range; a torque of the drive motor is less than a second predetermined torque; and a vehicle speed of the vehicle is greater than one or more of the second predetermined vehicle speeds; Here, the first predetermined torque is greater than the second predetermined torque, and the first predetermined vehicle speed is smaller than the second predetermined vehicle speed.

[0016] Optionally, the vehicle includes a relief valve for controlling a flow rate of the cooling flow passage, and the method further comprises: The method further includes requesting a relief valve of the vehicle to be forced to a closed state if, after starting the engine and cooling the drive motor, the flow rate of the cooling passage flowing through the drive motor is greater than a third predetermined cooling flow rate.

[0017] A second aspect of the present disclosure further provides an apparatus for cooling a stalled traction motor of a vehicle, the vehicle comprising: a traction motor, an engine, an engine-end oil pump, and a cooling passage, the engine being adapted to drive operation of the engine-end oil pump, the cooling passage connecting the engine-end oil pump and the traction motor, the apparatus comprising: A controller adapted to implement the steps of the method for cooling a stalled drive motor of the vehicle according to any of the first aspects above.

[0018] A third aspect of the present disclosure further provides a non-transitory computer readable storage medium having stored thereon a computer program which, when executed by a processor, implements the steps of the method for cooling a stalled drive motor of the vehicle as described in any of the first aspects above.

[0019] A fourth aspect of the present disclosure further provides a vehicle, the vehicle comprising: a drive motor; an engine; an engine end oil pump; a cooling passage; and a controller; the engine is adapted to drive the operation of the engine end oil pump; the cooling passage connects the engine end oil pump and the drive motor; The controller is adapted to implement the steps of a method for cooling a stalled drive motor of the vehicle as set forth in any of the first aspects above. Effect of the Invention

[0020] The above technical solutions can at least achieve the following technical effects:

[0021] When the driving mode of the vehicle is in a pure electric mode, and the vehicle meets a predetermined motor stall operating condition, and the current temperature of the driving motor is greater than the engine-assisted cooling start-up temperature, the vehicle engine start is controlled so that the engine end oil pump of the vehicle drives the coolant liquid in the cooling passage to cool the driving motor. With this method, when the vehicle is in a pure electric mode and the driving motor stalls, the vehicle engine is started to cool the driving motor, and the problem that the rotation speed of the wheel end oil pump is low due to the stall of the driving motor, and the coolant liquid cannot be provided enough to cool the driving motor, resulting in reduced service life and burning of the driving motor, is avoided.

[0022] Other features and advantages of the present disclosure are described, in part, in detail in the specific embodiments that follow. [Brief description of the drawings]

[0023] The drawings are provided for a further understanding of the present disclosure, constitute a part of the specification, and are intended to guide the present disclosure in conjunction with the following specific embodiments, but are not intended to constitute limitations thereon. [Figure 1] FIG. 1 is a schematic diagram illustrating a cooling system architecture. [Diagram 2] 4 is a flow chart illustrating a method for cooling a stalled traction motor of a vehicle according to an embodiment of the disclosure. [Diagram 3] 4 is a flow chart illustrating a method for cooling a stalled traction motor of another vehicle according to an embodiment of the present disclosure. [Figure 4] FIG. 1 is a block diagram illustrating an apparatus for cooling a stalled traction motor of a vehicle according to an embodiment of the present disclosure. [Diagram 5] FIG. 1 is a block diagram illustrating a vehicle according to an embodiment of the present disclosure. [Figure 6] FIG. 2 is a block diagram illustrating another vehicle according to an embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] Hereinafter, specific embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for the purpose of explaining and interpreting the present disclosure, and do not limit the present disclosure.

[0025] It should be understood that the steps described in the method embodiments of the present disclosure can be performed in a different order and / or in parallel. However, the method embodiments can include additional steps and / or omit steps shown. The scope of the present disclosure is not limited in this respect. As used herein, the term "including" and variations thereof are open-ended inclusions, i.e., "including but not limited to." The term "based on" refers to "based at least in part on." The term "an embodiment" refers to "at least one embodiment," the term "another embodiment" refers to "at least one other embodiment," and the term "some embodiments" refers to "at least some embodiments." Relevant definitions of other terms are provided in the following description.

[0026] It should be noted that the concepts of "first", "second", etc. mentioned in the present disclosure are only used to distinguish different devices, modules or units, and are not intended to limit the order or interdependence of the functions performed in these devices, modules or units. It should be noted that the modifications of "one" and "multiple" mentioned in the present disclosure are illustrative rather than limiting, and unless otherwise specified in the context, those skilled in the art should understand them as "one or more".

[0027] Currently, the cooling system architecture of a hybrid vehicle that does not have an electric oil pump is shown in FIG. 1. Both the wheel end oil pump 101 and the engine end oil pump 102 are mechanical pumps. The wheel end oil pump 101 is driven by the rotation of the wheels and is responsible for the low pressure oil passage (cooling and lubrication), while the engine end oil pump 102 is driven by the rotation of the engine and is responsible for the oil supply to the high pressure oil passage (hydraulic pressure of the clutch 108, etc.). At the same time, a control valve 103 is provided between the low pressure oil passage and the high pressure oil passage, and the control valve 103 includes at least a first state that allows the engine end oil pump 102 to supply oil to the cooling oil passage of the drive motor 104 and a second state that blocks it. When the hybrid vehicle is in a pure electric mode, the cooling operation of the wheel end oil pump 101 is mainly driven by the rotation of the wheels, and when the hybrid vehicle is in a hybrid mode, the engine end oil pump 102 performs the cooling operation together with the wheel end oil pump 101 by the drive of the engine. The drive motor 104 may be cooled when the heat dissipation fan 105 is operating. The relief valve 106 is an electromagnetic valve that controls the cooling flow rate of the cooling oil passage, and when there is no need to cool the drive motor 104, the relief valve 106 opens, allowing only a minimum flow rate of cooling oil (i.e., coolant) to flow to the drive motor 104, with the excess flowing back to the oil tank 107. When there is a need to cool the drive motor 104, the relief valve 106 closes, and all of the cooling oil exchanges heat with the outside via the cooling oil passage.

[0028] However, when a hybrid vehicle is in pure electric mode, if the drive motor stalls, the vehicle speed is low and the wheel end oil pump rotation speed is low, and sufficient coolant fluid cannot be provided to cool the drive motor, reducing the drive motor's lifespan and causing it to burn out.

[0029] In light of this, for hybrid vehicles not equipped with an electric oil pump, the present disclosure provides a method, apparatus, and vehicle for cooling a stalled drive motor of the vehicle to solve the above problems.

[0030] The following describes in detail the embodiments of the technical solutions of the present disclosure.

[0031] An embodiment of the present disclosure provides a method for cooling a stalled traction motor of a vehicle, the vehicle comprising: a traction motor, an engine, an engine-end oil pump, and a cooling passage, the engine is used to drive the operation of the engine-end oil pump, and the cooling passage connects the engine-end oil pump and the traction motor, as shown in FIG. 2 , the method includes: The method includes S201, when the driving mode of the vehicle is in a pure electric mode, and the vehicle satisfies a predetermined motor stall operating condition, and the current temperature of the driving motor is greater than an engine-assisted cooling start-up temperature, controlling and starting the engine of the vehicle, so that the engine-end oil pump of the vehicle drives the coolant liquid in the cooling passage to cool the driving motor.

[0032] By adopting the above method, when the driving mode of the vehicle is in a pure electric mode, the vehicle meets a predetermined motor stall operating condition, and the current temperature of the driving motor is greater than the engine-assisted cooling start temperature, the engine of the vehicle is controlled to start, so that the engine end oil pump of the vehicle drives the coolant liquid in the cooling passage to cool the driving motor. With this method, when the vehicle is in a pure electric mode and the driving motor stalls, the engine of the vehicle is started to cool the driving motor, so as to avoid the problem that the rotation speed of the wheel end oil pump is low due to the stall of the driving motor, and the coolant liquid cannot be provided enough to cool the driving motor, which reduces the life of the driving motor and causes it to burn out.

[0033] In order to allow those skilled in the art to further understand the method for cooling a stalled drive motor of a vehicle according to the present disclosure, each of the above steps will be described in detail below with examples.

[0034] In a possible aspect, the method further includes determining a first length of time for the temperature of the drive motor to reach a first predetermined temperature based on a temperature change rate of the drive motor and a current temperature of the drive motor, and decreasing the engine assisted cooling start-up temperature if the first length of time is less than or equal to the first predetermined length of time.

[0035] For example, decreasing the engine assist cooling start-up temperature when the first time length is equal to or less than a first predetermined time length may be: determining a target correction offset amount based on a temperature change rate of the drive motor and a predetermined relationship between the temperature change rate and the correction offset amount when the first time length is equal to or less than the first predetermined time length; and setting the difference between the first predetermined temperature and the target correction offset amount as the engine assist cooling start-up temperature.

[0036] Alternatively, decreasing the engine assist cooling start-up temperature when the first length of time is less than or equal to the first predetermined length of time may be equaling the engine assist cooling start-up temperature to a second predetermined temperature when the first length of time is less than or equal to the first predetermined temperature, the second predetermined temperature being less than the first predetermined temperature.

[0037] The first predetermined temperature is a maximum allowable temperature of the drive motor, the second predetermined temperature is a safe start-up temperature with the drive motor in a stalled condition, and an engine assisted cool start-up temperature is less than or equal to the first predetermined temperature.

[0038] It should be understood that under normal circumstances, the engine-assisted cooling start-up temperature is usually set as the maximum allowable temperature of the drive motor. However, due to a certain time delay in the temperature sensor, when the temperature sensor detects that the current temperature of the drive motor is higher than the maximum allowable temperature, the actual temperature of the drive motor will be much higher than the maximum allowable temperature, which may cause the drive motor to overheat and burn out. Therefore, the engine-assisted cooling start-up temperature can be adjusted according to the current temperature change rate and the maximum allowable temperature of the drive motor, for example, by lowering the engine-assisted cooling start-up temperature, the engine can be started early to participate in cooling the drive motor, thereby ensuring that the drive motor always operates within a reasonable temperature range and avoiding overheating and burning of the drive motor caused by the response delay of the temperature sensor.

[0039] For example, the predetermined relationship between the temperature change rate and the correction offset amount is determined by experiment and is shown in Table 1 below, where the temperature change rate is the temperature change rate of the driving motor every 3 seconds, and is obtained by rounding up or down.

[0040] [Table 1]

[0041] The engine assist cooling start temperature can be determined using the following formula: T=T0-A Here, T denotes the engine assist cooling start temperature, T0 denotes the maximum allowable temperature of the drive motor, and A denotes the correction offset amount, which can be found in Table 1 based on the current temperature change rate detected by the temperature sensor.

[0042] Alternatively, based on the safe start-up temperature in the stalled state of the drive motor, if the first time length is equal to or less than the first predetermined time length, the engine assist cooling start-up temperature is set as the safe start-up temperature (second predetermined temperature), and thus the engine is started early to participate in cooling the drive motor, thereby ensuring that the drive motor always operates in a reasonable temperature range and avoiding overheating and burning of the drive motor due to a delayed response of the temperature sensor. Alternatively, a relationship curve between the current temperature change rate and the engine assist cooling start-up temperature can be determined through experiments. In the relationship curve, when the current temperature change rate is 0, the engine assist cooling start-up temperature is equal to the maximum allowable temperature of the drive motor, and the larger the current temperature change rate is, the smaller the engine assist cooling start-up temperature becomes. Based on the relationship curve, the engine assist cooling start-up temperature is lowered to start the engine early to cool the drive motor, thereby ensuring that the drive motor always operates in a reasonable temperature range and avoiding overheating and burning of the drive motor due to a delayed response of the temperature sensor.

[0043] In one possible embodiment, the method further includes, if the first length of time is greater than a first predetermined length of time, the engine assisted cool start-up temperature is equal to a first predetermined temperature.

[0044] That is, if the time length for the temperature of the drive motor to reach the maximum allowable temperature is greater than the first predetermined time length, it indicates that the drive motor is not currently at risk of overheating and burning, so there is no need to start the engine early to participate in cooling the drive motor, and the engine-assisted cooling start-up temperature can be set to be equal to the maximum allowable temperature. If the time length for the temperature of the drive motor to reach the maximum allowable temperature is equal to or less than the first predetermined time length, it indicates that the drive motor is currently at risk of overheating and burning, so there is a need to start the engine early to participate in cooling the drive motor, and by lowering the engine-assisted cooling start-up temperature, it is possible to ensure that the drive motor always operates in a reasonable temperature range and avoid overheating and burning of the drive motor due to the response delay of the temperature sensor. The safe start-up temperature may be 80°C, and the maximum allowable temperature may be 110°C, which are specifically determined according to the physical characteristics of the drive motor, and the present disclosure is not specifically limited thereto. In a possible embodiment, the method further includes controlling the engine to stop operating after a second predetermined time length when it is determined that the vehicle meets the predetermined motor stall exit condition and the current temperature of the drive motor is less than the engine-assisted cooling stop temperature.

[0045] For example, when the vehicle meets a predetermined motor stall operating condition, and the vehicle meets a predetermined cooling end condition, and the current temperature of the driving motor is greater than the engine-assisted cooling start temperature, the engine is immediately started to participate in cooling the driving motor, to avoid overheating and burning of the driving motor. Then, when it is determined that the vehicle meets the predetermined cooling end condition and the current temperature of the driving motor is less than the engine-assisted cooling stop temperature, that is, when the driving motor no longer needs to participate in cooling the engine, the engine is turned off after a predetermined time period, so as not to frequently start the engine and cause losses to the engine, so that the state of the vehicle changes within a short time and it is possible to avoid restarting the engine to cool the driving motor. The engine-assisted cooling stop temperature is determined according to the physical characteristics of the driving motor, and may be, for example, 105°C, and the predetermined time period may be set based on experiments, and may be, for example, 14s, and the present disclosure is not limited thereto.

[0046] In a possible embodiment, the method further includes controlling the rotation speed of the engine based on a current temperature of the traction motor, where there is a positive correlation between the rotation speed of the engine and the current temperature of the traction motor. When the vehicle meets a predetermined motor stall operating condition and the flow rate through the cooling channel of the traction motor is greater than a first predetermined cooling flow rate, the heat dissipation fan of the vehicle is controlled to operate at a maximum rotation speed to cool the traction motor.

[0047] Additionally, the method further includes controlling the heat dissipation fan to stop operating when the vehicle meets a predetermined motor stall exit condition and a flow rate of the cooling passage through the traction motor is less than a second predetermined cooling flow rate, where the first predetermined cooling flow rate is greater than the second predetermined cooling flow rate.

[0048] The drive motor is cooled mainly by circulating a coolant liquid in a cooling passage, which removes heat generated by the drive motor while it is operating, and exchanges the heat with the outside via a heat dissipation system.

[0049] For example, there is a positive correlation between the rotation speed of the engine and the current temperature of the driving motor, that is, the higher the current temperature of the driving motor, the faster the heat needs to be dissipated, so the rotation speed of the engine is controlled to be high, and the cooling flow rate driven by the engine end oil pump is increased to take away more heat. In addition, when the vehicle meets a predetermined motor stall operating condition and the flow rate of the cooling flow passage flowing through the driving motor is greater than the first predetermined cooling flow rate, the heat dissipation fan of the vehicle is controlled to operate at the maximum rotation speed, so that the coolant liquid dissipates heat as quickly as possible and cools the driving motor.

[0050] However, when the vehicle meets a predetermined motor stall termination condition and the flow rate of the cooling passage through the drive motor is less than the second predetermined cooling flow rate, the heat dissipation fan is controlled to stop operating, thereby preventing the heat dissipation fan from always operating at its maximum rotation speed, which would cause unnecessary energy consumption.

[0051] Here, the first predetermined cooling flow rate and the second predetermined cooling flow rate can be determined by experiment, for example, the first predetermined cooling flow rate can be 3 L, and the second predetermined cooling flow rate can be 1.5 L, but the present disclosure does not specifically limit this, as long as it is ensured that the first predetermined cooling flow rate is greater than the second predetermined cooling flow rate.

[0052] In a possible embodiment, the start-up of a vehicle engine is controlled by the following method, the engine is controlled to output a predetermined rotation speed, and the vehicle's heat dissipation fan is controlled to operate at maximum rotation speed and cool the drive motor.

[0053] Furthermore, the method further includes determining that the vehicle meets a predetermined motor stall exit condition and determining that the current temperature of the drive motor is less than an engine assisted cooling stop temperature, and controlling the heat dissipation fan to stop operating and controlling the engine to stop operating after a second predetermined length of time, or controlling the engine and the heat dissipation fan to stop operating after the second predetermined length of time.

[0054] That is, when the driving mode of the vehicle is in the pure electric mode, and the vehicle meets a predetermined motor stall operating condition, and the current temperature of the driving motor is greater than the engine-assisted cooling start temperature, the engine is controlled to operate at a predetermined rotation speed to drive the engine end oil pump, and the heat dissipation fan of the vehicle is controlled to operate at the maximum rotation speed to cool the driving motor. The predetermined rotation speed is determined by experimentation while satisfying both the heat dissipation requirement and the energy saving requirement, so as to better cool the driving motor while satisfying both the heat dissipation requirement and the energy saving requirement.

[0055] Furthermore, when the vehicle meets a predetermined motor stall end condition and the current temperature of the driving motor is lower than the engine-assisted cooling stop temperature, the heat dissipation fan is controlled to stop operating, and the engine is controlled to stop operating after a second predetermined time. Or, when the vehicle meets a predetermined motor stall end condition and the current temperature of the driving motor is lower than the engine-assisted cooling stop temperature, the engine and the heat dissipation fan can be controlled to stop operating after a second predetermined time, so as to avoid unnecessary energy consumption. The second predetermined time can be set as required, and the present disclosure is not limited thereto.

[0056] In a possible embodiment, the vehicle includes a relief valve for controlling the flow rate of the cooling passage, and the method further includes, after starting the engine to cool the drive motor, requesting the vehicle's relief valve to be forced closed if the flow rate of the cooling passage through the drive motor is greater than a third predetermined cooling flow rate.

[0057] For example, after starting the engine to cool the drive motor, if the flow rate of the cooling passage flowing through the drive motor is greater than a third predetermined cooling flow rate, the vehicle's relief valve is requested to enter a forced closed state, so that all the coolant cools the drive motor through the vehicle's cooling passage, thereby improving the cooling effect of the drive motor. Then, if the vehicle meets the predetermined motor stall end condition or the flow rate of the cooling passage is less than the predetermined flow rate for opening the relief valve, the relief valve is requested to end the forced closed state, thereby reducing unnecessary power energy.

[0058] In addition, the relief valve needs to be energized to close, and the electrical resistance therein continues to generate heat. Therefore, if the relief valve is controlled to close immediately after the engine is started, that is, when the flow rate of the cooling passage is low, the relief valve will rapidly heat up and burn out. Therefore, the embodiment of the present disclosure requires the vehicle's relief valve to be forced to close after the engine is started to cool the driving motor, thereby avoiding the relief valve from burning out. Therefore, after the engine is started to cool the driving motor, the vehicle's relief valve can be controlled based on whether the flow rate of the cooling passage meets a predetermined requirement, for example, if the flow rate of the cooling passage is greater than 1.5L, the relief valve is controlled to close, and if the flow rate of the cooling passage is less than 3L after the relief valve is closed, the relief valve is controlled to open, which can be specifically set as needed, and the present disclosure is not limited thereto.

[0059] In a possible aspect, the predetermined motor stall activation conditions include the vehicle range being in a forward range or a reverse range, the torque of the drive motor being greater than or equal to a first predetermined torque, and the vehicle speed being less than or equal to the first predetermined vehicle speed, and the predetermined motor stall exit conditions include the vehicle range not being in a forward range or a reverse range, the torque of the drive motor being less than a second predetermined torque, and the vehicle speed being greater than one or more of the second predetermined vehicle speeds, where the first predetermined torque is greater than the second predetermined torque and the first predetermined vehicle speed is less than the second predetermined vehicle speed.

[0060] Exemplarily, the first predetermined torque, the first predetermined vehicle speed, and the first predetermined temperature are determined according to experiments and the physical characteristics of the vehicle. For example, the first predetermined torque may be 150N·m, and the first predetermined vehicle speed may be 3KM / h, and the present disclosure does not specifically limit this. The second predetermined torque, the second predetermined vehicle speed, and the second predetermined temperature are determined according to experiments and the physical characteristics of the vehicle. For example, the second predetermined torque may be 10N·m, and the second predetermined vehicle speed may be 5KM / h, and the present disclosure does not specifically limit this.

[0061] For example, when the vehicle is in a pure electric mode, the vehicle may determine that the vehicle's drive motor needs to be cooled in a stalled state when the vehicle's range is in a forward range or a reverse range, the torque of the drive motor is equal to or greater than a first predetermined torque, the current vehicle speed of the vehicle is equal to or less than a first predetermined vehicle speed, and the current temperature of the drive motor is greater than an engine-assisted cooling start temperature, and may further start the engine, so that the engine-end oil pump of the vehicle drives the coolant liquid in the cooling passage to cool the drive motor, thereby avoiding the drive motor from being shortened in life and burning out. Then, when the vehicle meets a predetermined motor stall end condition, i.e., the drive motor does not need the engine to participate in cooling, the engine may be turned off after a predetermined length of time to avoid frequent engine start-up and loss to the engine.

[0062] Furthermore, when the current vehicle speed is greater than the first predetermined vehicle speed and less than the second predetermined vehicle speed, or when the torque of the drive motor is less than the first predetermined torque and greater than the second predetermined torque, the engine is maintained in the current operating state, the effect of vehicle speed fluctuations or torque fluctuations on the engine operating state is reduced, and the engine is not started frequently to cause loss to the engine.

[0063] In order to make it easier for those skilled in the art to understand the method according to the embodiment of the present disclosure, the steps of the method for cooling a stalled drive motor of a vehicle according to the embodiment of the present disclosure are described in detail below. As shown in Figure 3, the method includes the following steps: In S301, it is determined that the driving mode of the vehicle is in a pure electric mode, and it is determined that the vehicle is in a predetermined motor stall operating condition and the current temperature of the driving motor is greater than the engine assisted cooling start-up temperature. In S302, the vehicle engine is started. In S303, it is determined whether the flow rate in the cooling channel is greater than a first predetermined cooling flow rate.

[0064] Furthermore, if the flow rate in the cooling channel is greater than the first predetermined cooling flow rate, then execute step S304; otherwise, execute step S308. S304 requests that the vehicle's heat dissipation fan be operated at maximum rotation speed. In S305, it is determined whether the flow rate in the cooling channel is greater than a third predetermined cooling flow rate.

[0065] Furthermore, if the flow rate of the cooling channel is greater than the third predetermined cooling flow rate, then execute step S306; otherwise, execute step S310.

[0066] In S306, a request is made for the vehicle's relief valve to be forced closed. In S307, it is determined whether the vehicle meets any predetermined motor stall exit condition and whether the flow rate in the cooling channel is less than a second predetermined cooling flow rate.

[0067] Furthermore, if the vehicle meets any predetermined motor stall exit condition and the cooling channel flow rate is less than the second predetermined cooling flow rate, then execute step S308; otherwise, execute step S304.

[0068] S308 requests that the vehicle's heat dissipation fan stop operating. In S309, it is determined whether the vehicle meets any predetermined motor stall exit condition and whether the flow rate in the cooling channel is less than the start flow rate.

[0069] Additionally, if the vehicle meets any predetermined motor stall exit condition or the cooling channel flow rate is less than the start flow rate, then step S310 is executed; otherwise, step S306 is executed.

[0070] S310 requests that the vehicle's relief valves open. In S311, it is determined whether the vehicle meets any predetermined motor stall exit conditions and whether the current temperature of the traction motor is less than the engine assist cooling stop temperature.

[0071] Furthermore, if it is determined that the vehicle meets any predetermined motor stall end condition and the current temperature of the traction motor is less than the engine assist cooling stop temperature, then execute step S312; otherwise, keep the engine running. S312 shuts off the engine after a predetermined amount of time.

[0072] By adopting the above method, when the vehicle is in pure electric mode and the drive motor stalls, the vehicle engine is started, and the engine-end oil pump of the vehicle drives the coolant in the cooling passage to cool the drive motor, thereby avoiding the problem that the wheel-end oil pump has a low rotation speed due to the drive motor stall, and cannot provide enough coolant to cool the drive motor, resulting in reduced service life and burnout of the drive motor. The heat dissipation fan and the relief valve are controlled to speed up the heat exchange with the outside, thereby improving the cooling effect of the drive motor.

[0073] Based on the same inventive concept, the present disclosure further provides an apparatus for cooling a stalled traction motor of a vehicle, the vehicle comprising a traction motor, an engine, an engine-end oil pump and a cooling passage, the engine being used to drive the operation of the engine-end oil pump, and the cooling passage connecting the engine-end oil pump and the traction motor. As shown in FIG. 4, the apparatus 400 includes: A controller 401 is provided for implementing the steps of the method for cooling a stalled drive motor of the vehicle.

[0074] Optionally, the controller 401 may: When the driving mode of the vehicle is in a pure electric mode, and the vehicle meets a predetermined motor stall operating condition, and the current temperature of the driving motor is greater than an engine-assisted cooling start-up temperature, the engine of the vehicle is controlled to start, and the engine-end oil pump of the vehicle is used to drive the coolant liquid in the cooling passage to cool the driving motor.

[0075] Optionally, the controller 401 further comprises: determining a first time length for the temperature of the driving motor to reach a first predetermined temperature based on a temperature change rate of the driving motor and a current temperature of the driving motor; and If the first length of time is less than or equal to a first predetermined length of time, the engine assist cooling start temperature is decreased.

[0076] Optionally, the controller 401 further comprises: If the first time length is equal to or less than a first predetermined time length, determining a target correction offset amount based on a temperature change rate of the driving motor and a predetermined relationship between the temperature change rate and a correction offset amount; and The difference between the first predetermined temperature and the target correction offset amount is used to set the engine assist cooling start temperature.

[0077] Optionally, the controller 401 further comprises: If the first length of time is less than or equal to a first predetermined length of time, the engine assist cooling start temperature is used to be equal to a second predetermined temperature, the second predetermined temperature being less than the first predetermined temperature.

[0078] Optionally, the controller 401 further comprises: If the first length of time is greater than a first predetermined length of time, the engine assist cooling start temperature is used to be equal to the first predetermined temperature.

[0079] Optionally, the controller 401 further comprises: The engine is controlled to stop operating after a second predetermined length of time if the vehicle determines that a predetermined motor stall exit condition is met and the current temperature of the traction motor is less than an engine assist cooling stop temperature.

[0080] Optionally, the first predetermined temperature is a maximum allowable temperature of the drive motor, the second predetermined temperature is a safe start-up temperature when the drive motor is in a stalled condition, and the engine assisted cool start-up temperature is less than or equal to the first predetermined temperature.

[0081] Optionally, the controller 401 further comprises: Controlling the rotation speed of the engine based on the current temperature of the traction motor, where there is a positive correlation between the rotation speed of the engine and the current temperature of the traction motor; When the vehicle satisfies a predetermined motor stall operating condition and the flow rate of the cooling passage flowing through the drive motor is greater than a first predetermined cooling flow rate, the heat dissipation fan of the vehicle is controlled to operate at a maximum rotation speed to cool the drive motor.

[0082] Optionally, the controller 401 further comprises: When the vehicle satisfies a predetermined motor stall termination condition and the flow rate of the cooling flow passage through the traction motor is less than a second predetermined cooling flow rate, the cooling fan is controlled to stop operating; Here, the first predetermined cooling flow rate is greater than the second predetermined cooling flow rate.

[0083] Optionally, the controller 401 further comprises: Controlling the engine to output a predetermined rotational speed; and The vehicle's heat dissipation fan is controlled to operate at a maximum rotation speed, thereby cooling the drive motor.

[0084] Optionally, the controller 401 further comprises: determining that the vehicle meets a predetermined motor stall exit condition and that the current temperature of the traction motor is less than an engine assist cooling stop temperature; and Controlling the heat dissipation fan to stop operation and, after a second predetermined time period, controlling the engine to stop operation, or controlling the engine and the heat dissipation fan to stop operation after a second predetermined time period.

[0085] Optionally, the predetermined motor stall operating condition includes that the range of the vehicle is in a forward range or a reverse range, that the torque of the drive motor is equal to or greater than a first predetermined torque, and that the vehicle speed is equal to or less than a first predetermined vehicle speed; the predetermined motor stall termination conditions include: a range of the vehicle is not a forward range or a reverse range; a torque of the drive motor is less than a second predetermined torque; and a vehicle speed of the vehicle is greater than one or more of the second predetermined vehicle speeds; Here, the first predetermined torque is greater than the second predetermined torque, and the first predetermined vehicle speed is smaller than the second predetermined vehicle speed.

[0086] Optionally, the vehicle includes a relief valve for controlling the flow rate of the cooling passage, and the controller 401 further includes: After starting the engine to cool the drive motor, if the flow rate of the cooling passage flowing through the drive motor is greater than a third predetermined cooling flow rate, the relief valve of the vehicle is forced to close.

[0087] By adopting the above device, when the vehicle is in pure electric mode and the drive motor stalls, the vehicle engine is started to cool the drive motor, and the stalled drive motor causes the oil pump at the wheel end to rotate at a low speed, and is unable to provide enough coolant liquid to cool the drive motor, thereby reducing the lifespan of the drive motor and causing it to burn out.

[0088] In the above embodiment of the apparatus, the specific manner in which each module performs the operations has been described in detail in the embodiment related to the method, but will not be described in detail here.

[0089] An embodiment of the present disclosure further provides a non-transitory computer-readable storage medium having a computer program stored thereon, the computer program, when executed by a processor, implementing steps of a method for cooling a stalled drive motor of a vehicle according to the above embodiment.

[0090] An embodiment of the present disclosure further provides a vehicle 500, referring to FIG. 5 , comprising a drive motor 501, an engine 502, an engine end oil pump 503, a cooling passage 504 and a controller 505; The engine 502 is used to drive the engine end oil pump 503; The cooling passage 504 connects the engine end oil pump 503 and the drive motor 501, The controller 505 is used to implement the steps of the method for cooling a stalled traction motor of a vehicle according to the above embodiment.

[0091] An embodiment of the present disclosure further provides a vehicle, A memory in which a computer program is stored; and a processor for executing the computer program in the memory so as to implement the steps of the method for cooling a drive motor according to the above embodiment.

[0092] Fig. 6 is a block diagram illustrating another vehicle 600 according to an exemplary embodiment. Referring to Fig. 6, the vehicle 600 comprises one or more processors 622 and a memory 632 for storing computer programs executable by the processor 622. The computer programs stored in the memory 632 may comprise one or more modules, each corresponding to a set of instructions. It is noted that the processor 622 may be arranged to execute the computer programs to perform the method for cooling a drive motor described above.

[0093] The vehicle 600 may further include a power assembly 626 and a communication assembly 660, where the power assembly 626 may be arranged to perform power management of the vehicle 600, and the communication assembly 660 may be arranged to realize communication, e.g., wired or wireless communication, of the vehicle 600. The vehicle 600 may further include an input / output (I / O) interface 668. The vehicle 600 may operate an operating system, e.g., Windows Server™, Mac OS X™, Unix™, Linux™, etc., stored in the memory 632.

[0094] In another exemplary embodiment, a computer-readable storage medium including program instructions is further provided, which, when executed by a processor, realizes the steps of the method for cooling the drive motor. For example, the non-transitory computer-readable storage medium may be a memory 632 including the program instructions, which can be executed by a processor 622 of the vehicle 600 to complete the method for cooling the drive motor.

[0095] In another exemplary embodiment, a computer program product is further provided, the computer program product including a computer program executable by a programmable device, the computer program being used to execute code portions of a method for cooling a stalled drive motor of the vehicle when executed by the programmable device.

[0096] Although the preferred embodiments of the present disclosure have been described in detail above with reference to the drawings, the present disclosure is not limited to the specific details of the above embodiments. Within the technical concept of the present disclosure, the technical solutions of the present disclosure may be modified in a number of simple ways, and all of these simple modifications fall within the scope of protection of the present disclosure.

[0097] It should be noted that the specific technical features described in the above specific embodiments may be combined in any suitable manner if not contradictory, and in order to avoid unnecessary duplication, the present disclosure does not separately describe various possible combination methods.

[0098] In addition, various different embodiments of the present disclosure should be considered as being disclosed in the present disclosure as long as they do not violate the concept of the present disclosure. (CROSS REFERENCE TO RELATED APPLICATIONS)

[0099] This application claims priority to a Chinese patent application, bearing application number 202210188260.0 and title "Method, Apparatus and Vehicle for Cooling a Stalled Drive Motor of a Vehicle," filed with the China Patent Office on February 28, 2022, the entire contents of which are incorporated herein by reference.

Claims

1. A method for cooling a stalled traction motor of a vehicle, the vehicle (500) comprising a traction motor (501), an engine (502), an engine-end oil pump (503) and a cooling passage (504), the engine (502) being used to drive the operation of the engine-end oil pump (503), the cooling passage (504) connecting the engine-end oil pump (503) and the traction motor (501), the method comprising: A method for cooling a stalled traction motor of a vehicle, comprising: when a driving mode of the vehicle (500) is in a pure electric mode, and the vehicle (500) satisfies a predetermined motor stall operating condition, and a current temperature of the traction motor is greater than an engine assisted cooling start-up temperature, controlling the start-up of an engine (502) of the vehicle (500), and causing an engine-end oil pump (503) of the vehicle (500) to drive coolant liquid in the cooling passage (504) to cool the traction motor (501).

2. The method comprises: determining a first time length for the temperature of the driving motor (501) to reach a first predetermined temperature based on a temperature change rate of the driving motor (501) and a current temperature of the driving motor (501); and 2. The method of claim 1, further comprising: decreasing the engine assisted cooled start-up temperature if the first length of time is less than or equal to a first predetermined length of time.

3. Decreasing the engine assist cooling start temperature if the first length of time is less than or equal to a first predetermined length of time. If the first time length is equal to or less than a first predetermined time length, determining a target correction offset amount based on a temperature change rate of the driving motor (501) and a predetermined relationship between the temperature change rate and a correction offset amount; and 3. The method of claim 2, further comprising: determining the engine assisted cool start temperature as the difference between the first predetermined temperature and the target correction offset amount.

4. Decreasing the engine assist cooling start temperature if the first length of time is less than or equal to a first predetermined length of time.

3. The method of claim 2, further comprising: if the first length of time is less than or equal to a first predetermined length of time, the engine assisted cool start temperature is equal to a second predetermined temperature, the second predetermined temperature being less than the first predetermined temperature.

5. The method comprises:

5. The method of claim 2, further comprising: if the first length of time is greater than a first predetermined length of time, then the engine assisted cool start temperature is equal to the first predetermined temperature.

6. The method comprises:

5. The method of claim 2, further comprising controlling the engine to stop operation after a second predetermined length of time upon determining that the vehicle satisfies a predetermined motor stall exit condition and the current temperature of the drive motor is less than an engine assisted cooling stop temperature.

7. The method according to any one of claims 2 to 4, characterized in that the first predetermined temperature is a maximum allowable temperature of the drive motor (501), the second predetermined temperature is a safe start-up temperature when the drive motor (501) is in a stalled state, and the engine assisted cooling start-up temperature is less than or equal to the first predetermined temperature.

8. The method comprises: Controlling the rotation speed of the engine (502) based on the current temperature of the driving motor (501), where there is a positive correlation between the rotation speed of the engine (502) and the current temperature of the driving motor (502); 2. The method of claim 1, further comprising: when the vehicle (500) satisfies a predetermined motor stall operating condition and the flow rate of the cooling flow path (504) through the drive motor (501) is greater than a first predetermined cooling flow rate, controlling a heat dissipation fan of the vehicle (500) to operate at a maximum rotational speed to cool the drive motor (501).

9. The method comprises: The method further includes controlling the heat dissipation fan to stop operating when the vehicle (500) satisfies a predetermined motor stall end condition and the flow rate of the cooling flow path (504) flowing through the driving motor (501) is less than a second predetermined cooling flow rate; 9. The method of claim 8, wherein the first predetermined cooling flow rate is greater than the second predetermined cooling flow rate.

10. Controlling the start of the engine (502) of the vehicle (500) comprises: Controlling the engine (502) to output a predetermined rotational speed; and 2. The method of claim 1, further comprising controlling a heat dissipation fan of the vehicle (500) to operate at a maximum rotational speed to cool the drive motor (501).

11. The method comprises: determining that the vehicle (500) meets a predetermined motor stall exit condition and that the current temperature of the traction motor (501) is less than an engine assist cooling stop temperature; and 11. The method of claim 10, further comprising: controlling the heat sink fan to stop operating and controlling the engine (502) to stop operating after a second predetermined amount of time, or controlling the engine (502) and the heat sink fan to stop operating after a second predetermined amount of time.

12. The predetermined motor stall operating conditions include that the range of the vehicle (500) is in a forward range or a reverse range, that the torque of the drive motor (501) is equal to or greater than a first predetermined torque, and that the vehicle speed of the vehicle (500) is equal to or less than a first predetermined vehicle speed; The predetermined motor stall exit conditions include: the range of the vehicle is not a forward range or a reverse range; the torque of the drive motor is less than a second predetermined torque; and the vehicle speed of the vehicle is greater than one or more of the second predetermined vehicle speeds.

12. The method of claim 6, 9 or 11, wherein the first predetermined torque is greater than the second predetermined torque and the first predetermined vehicle speed is less than the second predetermined vehicle speed.

13. The vehicle (500) includes a relief valve, the relief valve being used to control the flow rate of the cooling channel (504), and the method further comprises:

2. The method of claim 1, further comprising: after starting the engine to cool the drive motor, when a flow rate of the cooling passage through the drive motor is greater than a third predetermined cooling flow rate, requesting a relief valve of the vehicle to be forced closed.

14. An apparatus for cooling a stalled drive motor of a vehicle, the vehicle (500) comprising a drive motor (501), an engine (502), an engine-end oil pump (503) and a cooling passage (504), the engine (502) being used to drive the operation of the engine-end oil pump (503), the cooling passage (504) connecting the engine-end oil pump (503) and the drive motor (501), the apparatus comprising: A device for cooling a stalled drive motor of a vehicle, comprising a controller (505) for implementing the steps of the method for cooling a stalled drive motor of a vehicle according to any one of claims 1 to 13.

15. 14. A non-transitory computer readable storage medium having a computer program stored thereon, the computer program storing the computer program when executed by a processor, the computer program implementing the steps of the method for cooling a stalled drive motor of a vehicle according to any one of claims 1 to 13.

16. A vehicle (500) comprising a drive motor (501), an engine (502), an engine-end oil pump (503), a cooling passage (504), and a controller (505); The engine (502) is used to drive the operation of the engine end oil pump (503); The cooling passage (504) connects the engine end oil pump (503) and the drive motor (501); A vehicle (500), characterized in that the controller (505) is used to implement the steps of the method for cooling a stalled drive motor of a vehicle according to any one of claims 1 to 13.

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