Motor temperature determination method of vehicle, and motor control method and device of vehicle

Abstract

The embodiment of the invention provides a vehicle motor temperature determination method and device and a vehicle motor control method and device. The method comprises the steps that a motor load, motor rotating speed information and the external environment temperature are obtained; the motor temperature is determined based on the motor load, the motor rotating speed information and the external environment temperature, the motor temperature is calculated through the motor load, the motor rotating speed information and the external environment temperature, no extra sensor needs to be installed, the space of other parts cannot be occupied, and the reliability of obtaining the motor temperature is improved; and after the temperature of the motor is determined, the working mode of the motor is controlled based on the temperature of the motor to protect the safety of the motor, so that the driving safety is improved.

Description

Technical Field

[0001] The present application belongs to the field of vehicle technology, and specifically relates to a method for determining the motor temperature of a vehicle, and a method and device for controlling the motor of a vehicle. Background Art

[0002] With the increasing demand for passenger car driving quality, active stabilizer bar technology, as an emerging automotive chassis technology, has an increasingly higher installation rate. The active stabilizer bar can be controlled by an electric motor, and excessively high motor temperature can cause driving safety problems.

[0003] In the prior art, multiple sensors are additionally installed on the vehicle to collect relevant parameters of the motor when it is working and calculate the temperature of the motor.

[0004] However, using the existing technology, the installation space of the active stabilizer bar is limited, and the additional installation of sensors will occupy the space of other components, and the reliability is not high. Summary of the invention

[0005] The embodiments of the present application provide a method for determining the motor temperature of a vehicle, a method and a device for controlling the motor of a vehicle, so as to solve the problems in the prior art that the installation space of the active stabilizer bar is limited, the additional installation of sensors will occupy the space of other components, and the reliability is not high.

[0006] In a first aspect, an embodiment of the present application provides a method for determining a motor temperature of a vehicle, the method comprising:

[0007] Obtain motor load, motor speed information and external ambient temperature;

[0008] The motor temperature is determined based on the motor load, the motor speed information and the ambient temperature.

[0009] Optionally, determining the motor temperature based on the motor load, motor speed information and external ambient temperature includes:

[0010] The stator copper loss, stator iron loss and mechanical loss of the motor are obtained based on the motor load and motor speed information;

[0011] Based on the motor parameters, the thermal resistance of the motor when it is working is obtained;

[0012] The motor temperature is obtained based on the stator copper loss, stator iron loss, mechanical loss data, thermal resistance when the motor is working, and the external ambient temperature.

[0013] Optionally, obtaining the heat generation thermal resistance of the motor when it is working based on the motor parameters includes:

[0014] The insulation thermal resistance is obtained based on the insulation thickness of the motor slot, the equivalent thermal conductivity of the motor insulation and the inner surface area of ​​the motor slot;

[0015] The duct surface thermal resistance is obtained based on the core length, the thermal conductivity of the core, the thermal conductivity of the air, the thermal conductivity of the base material, the stator slot bottom radius, the stator outer radius, the inner radius of the base duct, and the equivalent air gap thickness;

[0016] The convection exchange thermal resistance is obtained based on the surface convection exchange heat coefficient and the surface area of ​​the air duct;

[0017] The heat generation thermal resistance of the motor when it is working is obtained based on the insulation thermal resistance, the duct surface thermal resistance and the convection exchange thermal resistance.

[0018] Optionally, the heat generation thermal resistance of the motor when it is working is obtained based on the insulation thermal conduction thermal resistance, the duct surface thermal resistance and the convection exchange thermal resistance, including:

[0019] The sum of the insulation heat conduction thermal resistance, the air duct surface thermal resistance and the convection exchange thermal resistance is determined as the heat generation thermal resistance when the motor is working.

[0020] Optionally, the insulation thermal resistance is obtained based on the motor slot insulation thickness, the motor insulation equivalent thermal conductivity and the inner surface area of ​​the motor slot, including:

[0021]

[0022] Among them, R Cu-core is the insulation thermal resistance, δ is the insulation thickness of the electroplating tank, λ insu A is the equivalent thermal conductivity of the electrolytic cell insulation, slot is the inner surface area of ​​the motor slot.

[0023] Optionally, the duct surface thermal resistance is obtained based on the core length, the thermal conductivity of the core, the thermal conductivity of the air, the thermal conductivity of the base material, the stator slot bottom radius, the stator outer radius, the base duct inner radius, and the equivalent air gap thickness, including:

[0024]

[0025] Among them, R core-flu is the thermal resistance of the duct surface, l is the core length, λ core is the thermal conductivity of the core, λ air is the thermal conductivity of air, λ base is the thermal conductivity of the base material, r1 is the radius of the stator slot bottom, r2 is the outer radius of the stator, r3 is the inner radius of the base air duct, δ air is the equivalent air gap thickness.

[0026] Optionally, obtaining the convection exchange thermal resistance based on the surface convection exchange heat coefficient and the air duct surface area includes:

[0027]

[0028] Among them, R conve is the convection heat transfer resistance, λ flu is the surface convection heat transfer coefficient, A wind is the duct surface area.

[0029] Optionally, obtaining the motor temperature based on stator copper loss, stator iron loss, mechanical loss data, thermal resistance of the motor when it is working, and external ambient temperature includes:

[0030] Based on the stator copper loss, stator iron loss and mechanical loss data, the copper loss power value and iron loss power value of the motor when it is working are obtained;

[0031] The stator core temperature rise and the winding copper conductor temperature rise are obtained based on the copper loss power value, iron loss power value and the heat generation thermal resistance of the motor when the motor is working;

[0032] The motor temperature is obtained based on the stator core temperature rise, winding copper conductor temperature rise and external ambient temperature.

[0033] Optionally, obtaining the copper loss power value and the iron loss power value when the motor is working based on the stator copper loss, the stator iron loss, and the mechanical loss data includes:

[0034] The copper loss power value is equal to the stator copper loss;

[0035] The iron loss power value is equal to half of the sum of the stator iron loss and the mechanical loss.

[0036] Optionally, the step of obtaining the stator core temperature rise and the winding copper conductor temperature rise based on the copper power loss value, the iron power loss value and the heat generation thermal resistance of the motor when the motor is working includes:

[0037] Based on T Fe =(P Cu +P Fe )*(R core-flu +R conve ) to obtain the stator core temperature rise, where P Cu is the copper power consumption value, P Fe is the iron loss power value, R core-flu is the thermal resistance of the duct surface, R conve is the convection exchange thermal resistance;

[0038] Based on T Cu =P Cu *R Cu-core +(P Cu +P Fe )*(R core-flu +R conve ) to obtain the winding copper conductor temperature rise, where P Cu is the copper power consumption value, P Fe is the iron loss power value, Rcore-flu is the thermal resistance of the duct surface, R conve is the convection heat transfer resistance, R Cu-core is the insulation thermal resistance.

[0039] Optionally, obtaining the motor temperature based on the stator core temperature rise, the winding copper conductor temperature rise and the external ambient temperature includes:

[0040] The sum of the stator core temperature rise, the winding copper conductor temperature rise and the external environment temperature is determined as the motor temperature.

[0041] In a second aspect, an embodiment of the present application provides a motor control method for a vehicle, the method comprising:

[0042] Determine the motor temperature based on the motor load, motor speed information and the ambient temperature;

[0043] An operating mode of the motor is controlled based on the motor temperature.

[0044] Optionally, controlling the working mode of the motor based on the motor temperature includes:

[0045] When the temperature of the motor is greater than or equal to a first preset temperature threshold, the motor is cooled based on a steering state of a vehicle or a working state of an active stabilizer bar until the temperature of the motor is reduced to a second preset temperature threshold.

[0046] Optionally, cooling the motor based on the steering state of the vehicle or the working state of the active stabilizer bar until the temperature of the motor drops to a second preset temperature threshold includes:

[0047] If the steering state of the vehicle is continuous steering, or the working state of the active stabilizer bar is output torque, limiting the speed of the motor until the temperature of the motor decreases to a second preset temperature threshold;

[0048] or,

[0049] If the steering state of the vehicle is no steering, or the working state of the active stabilizer bar is no need to output torque, the motor is powered off until the temperature of the motor drops to a second preset temperature threshold.

[0050] Optionally, if the steering state of the vehicle is continuous steering, or the working state of the active stabilizer bar is output torque, limiting the speed of the motor until the temperature of the motor drops to a second preset temperature threshold includes:

[0051] If the steering state of the vehicle is continuous steering, or the working state of the active stabilizer bar is output torque, the lower bridge arm of the power tube is controlled to be cut off to achieve a three-phase short circuit to reduce the rotation speed of the motor.

[0052] Optionally, determining the motor temperature based on the motor load, motor speed information and external ambient temperature includes:

[0053] The stator copper loss, stator iron loss and mechanical loss of the motor are obtained based on the motor load and motor speed information;

[0054] Based on the motor parameters, the thermal resistance of the motor when it is working is obtained;

[0055] The motor temperature is obtained based on the stator copper loss, stator iron loss, mechanical loss data, thermal resistance when the motor is working, and the external ambient temperature.

[0056] Optionally, obtaining the heat generation thermal resistance of the motor when it is working based on the motor parameters includes:

[0057] The insulation thermal resistance is obtained based on the insulation thickness of the motor slot, the equivalent thermal conductivity of the motor insulation and the inner surface area of ​​the motor slot;

[0058] The duct surface thermal resistance is obtained based on the core length, the thermal conductivity of the core, the thermal conductivity of the air, the thermal conductivity of the base material, the stator slot bottom radius, the stator outer radius, the inner radius of the base duct, and the equivalent air gap thickness;

[0059] The convection exchange thermal resistance is obtained based on the surface convection exchange heat coefficient and the surface area of ​​the air duct;

[0060] The heat generation thermal resistance of the motor when it is working is obtained based on the insulation thermal resistance, the duct surface thermal resistance and the convection exchange thermal resistance.

[0061] Optionally, the heat generation thermal resistance of the motor when it is working is obtained based on the insulation thermal conduction thermal resistance, the duct surface thermal resistance and the convection exchange thermal resistance, including:

[0062] The sum of the insulation heat conduction thermal resistance, the air duct surface thermal resistance and the convection exchange thermal resistance is determined as the heat generation thermal resistance when the motor is working.

[0063] Optionally, obtaining the motor temperature based on stator copper loss, stator iron loss, mechanical loss data, thermal resistance of the motor when it is working, and external ambient temperature includes:

[0064] Based on the stator copper loss, stator iron loss and mechanical loss data, the copper loss power value and iron loss power value of the motor when it is working are obtained;

[0065] The stator core temperature rise and the winding copper conductor temperature rise are obtained based on the copper loss power value, iron loss power value and the heat generation thermal resistance of the motor when the motor is working;

[0066] The motor temperature is obtained based on the stator core temperature rise, the winding copper conductor temperature rise and the external ambient temperature.

[0067] Optionally, obtaining the copper loss power value and the iron loss power value when the motor is working based on the stator copper loss, the stator iron loss, and the mechanical loss data includes:

[0068] The copper loss power value is equal to the stator copper loss;

[0069] The iron loss power value is equal to half of the sum of the stator iron loss and the mechanical loss.

[0070] Optionally, obtaining the motor temperature based on the stator core temperature rise, the winding copper conductor temperature rise and the external ambient temperature includes:

[0071] The sum of the stator core temperature rise, the winding copper conductor temperature rise and the external environment temperature is determined as the motor temperature.

[0072] In a third aspect, an embodiment of the present application provides a device for determining a motor temperature of a vehicle, the device comprising:

[0073] The acquisition module is used to obtain the motor load, motor speed information and external environment temperature;

[0074] The determination module is used to determine the motor temperature based on the motor load, the motor speed information and the external environment temperature.

[0075] Optionally, the determination module is specifically used to obtain the stator copper loss, stator iron loss and mechanical loss of the motor based on the motor load and motor speed information; based on the motor parameters, obtain the thermal resistance of the motor when it is working; based on the stator copper loss, stator iron loss, mechanical loss data, the thermal resistance of the motor when it is working and the external ambient temperature, obtain the motor temperature.

[0076] Optionally, the determination module is specifically used to obtain the insulation thermal conductivity thermal resistance based on the motor slot insulation thickness, the motor insulation equivalent thermal conductivity and the inner surface area of ​​the motor slot; to obtain the duct surface thermal resistance based on the core length, the thermal conductivity of the core, the thermal conductivity of the air, the thermal conductivity of the base material, the stator slot bottom radius, the stator outer radius and the base air duct inner radius and the equivalent air gap thickness; to obtain the convection exchange thermal resistance based on the surface convection exchange thermal coefficient and the duct surface area; to obtain the heat generation thermal resistance of the motor when it is working based on the insulation thermal conductivity thermal resistance, the duct surface thermal resistance and the convection exchange thermal resistance.

[0077] Optionally, the determination module is specifically used to determine that the sum of the insulation heat conduction thermal resistance, the air duct surface thermal resistance and the convection exchange thermal resistance is the heat generation thermal resistance when the motor is working.

[0078] Optionally, the determination module is further used to obtain the insulation thermal resistance based on the motor slot insulation thickness, the motor insulation equivalent thermal conductivity and the motor slot inner surface area, including:

[0079]

[0080] Among them, R Cu-core is the insulation thermal resistance, δ is the insulation thickness of the electroplating tank, λ insu A is the equivalent thermal conductivity of the electrolytic cell insulation, slot is the inner surface area of ​​the motor slot.

[0081] Optionally, the determination module is further used to obtain the duct surface thermal resistance based on the core length, the thermal conductivity of the core, the thermal conductivity of the air, the thermal conductivity of the base material, the stator slot bottom radius, the stator outer radius, the base duct inner radius, and the equivalent air gap thickness, including:

[0082]

[0083] Among them, R core-flu is the thermal resistance of the duct surface, l is the core length, λ core is the thermal conductivity of the core, λ air is the thermal conductivity of air, λ base is the thermal conductivity of the base material, r1 is the radius of the stator slot bottom, r2 is the outer radius of the stator, r3 is the inner radius of the base air duct, δ air is the equivalent air gap thickness.

[0084] Optionally, the determination module is further used to obtain the convection exchange thermal resistance based on the surface convection exchange heat coefficient and the surface area of ​​the air duct, including:

[0085]

[0086] Among them, R conve is the convection heat transfer resistance, λ flu is the surface convection heat transfer coefficient, A wind is the duct surface area.

[0087] Optionally, the determination module is specifically used to obtain the copper loss power value and iron loss power value when the motor is working based on the stator copper loss, stator iron loss, and mechanical loss data; to obtain the stator core temperature rise and the winding copper conductor temperature rise based on the copper loss power value, iron loss power value, and the heating thermal resistance when the motor is working; to obtain the motor temperature based on the stator core temperature rise, the winding copper conductor temperature rise and the external ambient temperature.

[0088] Optionally, the determination module is specifically used to determine that the copper loss power value is equal to the stator copper loss; and the iron loss power value is equal to half of the sum of the stator iron loss and the mechanical loss.

[0089] Optionally, the determining module is specifically configured to: Fe =(P Cu +P Fe )*(R core-flu +Rconve ) to obtain the stator core temperature rise, where P Cu is the copper power consumption value, P Fe is the iron loss power value, R core-flu is the thermal resistance of the duct surface, R conve is the convection exchange thermal resistance; based on T Cu =P Cu *R Cu-core +(P Cu +P Fe )*(R core-flu +R conve ) to obtain the temperature rise of the winding copper conductor, where P Cu is the copper power consumption value, P Fe is the iron loss power value, R core-flu is the thermal resistance of the duct surface, R conve is the convection heat transfer resistance, R Cu-core is the insulation thermal resistance.

[0090] Optionally, the determination module is further used to determine the sum of the stator core temperature rise, the winding copper conductor temperature rise and the external ambient temperature as the motor temperature.

[0091] In a fourth aspect, an embodiment of the present application provides a motor control device for a vehicle, the device comprising:

[0092] A determination module, used to determine the motor temperature based on the motor load, motor speed information and external environment temperature;

[0093] A control module is used to control the working mode of the motor based on the motor temperature.

[0094] Optionally, the control module is further used to cool the motor when the motor temperature is greater than or equal to a first preset temperature threshold, based on the steering state of the vehicle or the working state of the active stabilizer bar, until the motor temperature drops to a second preset temperature threshold.

[0095] Optionally, the control module is specifically used to limit the speed of the motor until the temperature of the motor drops to a second preset temperature threshold if the steering state of the vehicle is continuous steering, or the working state of the active stabilizer bar is output torque; or, if the steering state of the vehicle is no steering, or the working state of the active stabilizer bar is no need to output torque, cut off power to the motor until the temperature of the motor drops to a second preset temperature threshold.

[0096] Optionally, the control module is also used to control the cutting off of the lower bridge arm of the power tube to achieve a three-phase short circuit to reduce the speed of the motor if the steering state of the vehicle is continuous steering, or the working state of the active stabilizer bar is output torque.

[0097] Optionally, the determination module is specifically used to obtain the stator copper loss, stator iron loss and mechanical loss of the motor based on the motor load and motor speed information; based on the motor parameters, obtain the thermal resistance of the motor when it is working; based on the stator copper loss, stator iron loss, mechanical loss data, the thermal resistance of the motor when it is working and the external ambient temperature, obtain the motor temperature.

[0098] Optionally, the determination module is specifically used to obtain the insulation thermal conductivity thermal resistance based on the motor slot insulation thickness, the motor insulation equivalent thermal conductivity and the inner surface area of ​​the motor slot; to obtain the duct surface thermal resistance based on the core length, the thermal conductivity of the core, the thermal conductivity of the air, the thermal conductivity of the base material, the stator slot bottom radius, the stator outer radius and the base air duct inner radius and the equivalent air gap thickness; to obtain the convection exchange thermal resistance based on the surface convection exchange thermal coefficient and the duct surface area; to obtain the heat generation thermal resistance of the motor when it is working based on the insulation thermal conductivity thermal resistance, the duct surface thermal resistance and the convection exchange thermal resistance.

[0099] Optionally, the determination module is further used to determine that the sum of the insulation heat conduction thermal resistance, the air duct surface thermal resistance and the convection exchange thermal resistance is the heat generation thermal resistance when the motor is working.

[0100] Optionally, the determination module is specifically used to obtain the copper loss power value and iron loss power value when the motor is working based on the stator copper loss, stator iron loss, and mechanical loss data; to obtain the stator core temperature rise and the winding copper conductor temperature rise based on the copper loss power value, iron loss power value, and the heating thermal resistance when the motor is working; to obtain the motor temperature based on the stator core temperature rise, the winding copper conductor temperature rise and the external ambient temperature.

[0101] Optionally, the determination module is specifically used to determine that the copper loss power value is equal to the stator copper loss; and the iron loss power value is equal to half of the sum of the stator iron loss and the mechanical loss.

[0102] Optionally, the determination module is further used to determine the sum of the stator core temperature rise, the winding copper conductor temperature rise and the external ambient temperature as the motor temperature.

[0103] In a fifth aspect, an embodiment of the present application provides an electronic device, comprising: a processor and a memory, wherein the memory stores programs or instructions that can be run on the processor, and when the programs or instructions are executed by the processor, the steps of the vehicle motor temperature determination method as described in any one of the first aspect or the vehicle motor control method as described in the second aspect are implemented.

[0104] In a sixth aspect, an embodiment of the present application provides a vehicle, comprising: a processor and a memory, wherein the memory stores programs or instructions that can be executed on the processor, and when the programs or instructions are executed by the processor, the steps of the vehicle motor temperature determination method as described in any one of the first aspect or the vehicle motor control method as described in the second aspect are implemented.

[0105] In the seventh aspect, an embodiment of the present application provides a computer-readable storage medium, on which a program or instruction is stored. When the program or instruction is executed by a processor, the method for determining the motor temperature of a vehicle as described in any one of the first aspect or the steps of the method for controlling the motor of a vehicle as described in the second aspect are implemented.

[0106] In an eighth aspect, an embodiment of the present application provides a computer program product, which, when executed by a processor of a vehicle or a cloud server, implements the steps of the vehicle motor temperature determination method as described in any one of the first aspect or the vehicle motor control method as described in the second aspect.

[0107] The vehicle motor temperature determination method, vehicle motor control method and device provided in the embodiments of the present application obtain the motor load, motor speed information and external ambient temperature; determine the motor temperature based on the motor load, the motor speed information and the external ambient temperature, thereby realizing the calculation of the motor temperature through the motor load, the motor speed information and the external ambient temperature, without the need for additional sensors, without occupying the space of other components, and improving the reliability of obtaining the motor temperature; and after determining the motor temperature, controlling the working mode of the motor based on the motor temperature to protect the motor safety, thereby improving driving safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0108] Figure 1 A schematic diagram of the structure of a motor temperature estimation module for an active stabilizer bar provided in an embodiment of the present application;

[0109] Figure 2 A schematic flow chart of a method for determining the motor temperature of a vehicle provided in an embodiment of the present application;

[0110] Figure 3 A schematic flow chart of another method for determining the motor temperature of a vehicle provided in an embodiment of the present application;

[0111] Figure 4 A schematic flow chart of another method for determining the motor temperature of a vehicle provided in an embodiment of the present application;

[0112] Figure 5 A schematic flow chart of another method for determining the motor temperature of a vehicle provided in an embodiment of the present application;

[0113] Figure 6 A schematic flow chart of a motor control method for a vehicle provided in an embodiment of the present application;

[0114] Figure 7 A schematic flow chart of another motor control method for a vehicle provided in an embodiment of the present application;

[0115] Figure 8 A schematic flow chart of a method for determining the motor temperature of a vehicle and a method for controlling the motor of the vehicle provided in an embodiment of the present application;

[0116] Fig. 9 A schematic diagram of the structure of a motor temperature determination device for a vehicle is provided for an embodiment of the present application;

[0117] Fig.10 A schematic structural diagram of a motor control device for a vehicle is provided in an embodiment of the present application. DETAILED DESCRIPTION

[0118] The technical solutions in the embodiments of the present application will be clearly described below in conjunction with the drawings in the embodiments of the present application. All other embodiments obtained by ordinary technicians in this field based on the embodiments in the present application belong to the scope of protection of the present application.

[0119] The terms "first", "second", etc. of the present application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the terms used in this way can be interchangeable under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than those illustrated or described herein, and the objects distinguished by "first" and "second" are generally of the same type, and the number of objects is not limited.

[0120] In the related art, multiple sensors are installed around the motor to calculate the temperature of the motor based on the motor current detected by the current sensor, the rotation frequency detected by the rotation frequency sensor, and the ambient temperature detected by the ambient temperature sensor. This method uses multiple external sensors to correct the estimated temperature of the motor, which increases the total cost of the system. The more sensors there are, the more risk points of failure. The failure of any sensor may affect the performance of the entire system, resulting in low reliability of this method. In addition, no other methods other than external cooling are used to achieve motor cooling, which does not meet the requirements of vehicle driving safety.

[0121] In order to monitor the temperature of a vehicle motor, the present application provides a method for determining the motor temperature of a vehicle, which can determine the motor temperature based on motor parameters, motor load, motor speed information and external ambient temperature, thereby improving the reliability of determining the motor temperature, taking corresponding methods to cool the motor under abnormal working temperatures, and improving driving safety when the motor is overheated. A vehicle motor control method is provided, which controls the working mode of the motor based on the motor temperature, so that the motor is in a safer working state, thereby improving driving safety.

[0122] The method for determining the motor temperature of a vehicle provided in the present application is applicable to motors installed in the vehicle, without limiting the type of motors. The present application takes the motor of the vehicle's active stabilizer bar as an example.

[0123] The following embodiments of the present application can be executed by a vehicle. Existing vehicles are equipped with active stabilizer bars. The active stabilizer bar applies an anti-roll torque to the vehicle in real time through a built-in motor to suppress the body roll, realize active stability control of the vehicle, and improve the stability of the vehicle during driving. If the temperature of the motor in the active stabilizer bar is too high, the output torque will decrease, causing the vehicle to roll, affecting the safety of the entire vehicle. Therefore, monitoring the temperature of the motor in the active stabilizer bar during vehicle driving is a key link to ensure safety. By monitoring the temperature of the motor and taking measures to cool the motor when the motor temperature exceeds the first preset temperature threshold, the vehicle stability problem caused by the excessive temperature of the motor of the active stabilizer bar is reduced, thereby improving the safety of vehicle driving.

[0124] Figure 1 A schematic diagram of a motor temperature estimation module for an active stabilizer bar provided in an embodiment of the present application is shown in FIG. Figure 1 As shown, it includes: a motor body temperature estimation module 11, a temperature sensor 12 and a vehicle active stabilizer bar motor temperature estimation module 13. Among them, the motor body temperature estimation module 11 is used to calculate the heating thermal resistance generated when the motor is working, and the stator copper loss, stator iron loss and mechanical loss are obtained through the motor load and motor speed information. The stator copper loss, stator iron loss and mechanical loss and motor parameters are input into the motor body temperature estimation module 11 to obtain the heating thermal resistance generated when the motor is working, and the stator core temperature rise and the winding copper conductor temperature rise are output. The temperature sensor 12 is used to collect the external environment temperature, and the stator core temperature rise, the winding copper conductor temperature rise and the external environment temperature collected by the temperature sensor 12 are input into the vehicle active stabilizer bar motor temperature estimation module 13 to obtain the motor temperature.

[0125] The technical solution of the method for determining the motor temperature of a vehicle is described below with several specific embodiments:

[0126] Figure 2A flow chart of a method for determining the motor temperature of a vehicle provided in an embodiment of the present application. The method of this embodiment is applied to Figure 1 The motor temperature estimation module shown in Figure 2 As shown:

[0127] S21: Obtain motor load, motor speed information and external environment temperature.

[0128] The motor load of the active stabilizer bar mainly comes from vehicle roll control, wheel grip improvement, yaw stability control, passability control and comfort control. The motor needs to provide corresponding torque to achieve the above functions according to the actual driving status and needs of the vehicle.

[0129] For example, when a vehicle is turning, the vehicle body will tilt outward due to centrifugal force. The active stabilizer bar generates an anti-roll torque through a built-in motor to reduce the body roll. The generation of the torque requires the motor or actuator to overcome the force of the vehicle roll, thereby generating a load.

[0130] The heavier the motor load, the higher the current. The heat generated by the motor is directly related to the current. The higher the current, the greater the heat generated, and the higher the temperature of the motor. In other words, the greater the motor load, the higher the temperature of the motor.

[0131] The motor speed information refers to the speed at which the motor rotates. An increase in the motor speed will lead to an increase in internal friction and loss in the motor, thereby generating more heat and causing the motor temperature to rise.

[0132] The external environment temperature can be obtained by a temperature sensor. The temperature sensor can directly measure the temperature of the external environment of the vehicle, and convert the temperature signal into an electrical signal, which is transmitted to the vehicle active stabilizer bar motor temperature estimation module.

[0133] S22: Determine the motor temperature based on the motor load, motor speed information and external environment temperature.

[0134] The motor temperature is composed of the temperature generated by the motor itself and the external environment temperature.

[0135] In this embodiment, by acquiring the motor load, motor speed information and external ambient temperature; determining the motor temperature based on the motor load, the motor speed information and the external ambient temperature, it is possible to obtain the motor temperature when the motor is working without the need to additionally install multiple sensors, does not occupy the space of other components, and improves the reliability of determining the motor temperature.

[0136] Figure 3 A flow chart of another method for determining the motor temperature of a vehicle provided in an embodiment of the present application is shown as follows: Figure 3 As shown, Figure 3 is Figure 2 On the basis of the illustrated embodiment, further, a possible implementation of S22 is as follows:

[0137] S221: Obtaining the stator copper loss, stator iron loss and mechanical loss of the motor based on the motor load and motor speed information.

[0138] The stator is the stationary part of the motor, which consists of three parts: the stator iron core, the stator winding and the frame. The main function of the stator in the motor is to generate a rotating magnetic field. The stator generates heat during operation, which increases the temperature of the motor.

[0139] Stator copper loss refers to the loss caused by the wire resistance when the current passes through the motor winding. The higher the stator temperature, the greater the DC resistance of the stator winding. At the same current, the greater the loss, which leads to an increase in the motor temperature.

[0140] Stator iron loss is mainly affected by the magnetic field frequency, stator and rotor, sleeve structure and material, including hysteresis loss and eddy current loss. Stator iron loss Iron loss will cause heat to be generated inside the motor, thus affecting the motor temperature.

[0141] Mechanical losses are mainly affected by speed, load, rotor surface roughness, and lubrication level at the stator-rotor junction, including bearing friction loss and windage loss. Mechanical losses are converted into heat energy during motor operation, increasing the motor temperature.

[0142] The motor load and motor speed information in the active stabilizer bar can be collected by the control board. The motor load and motor speed information collected are used to obtain the motor's stator copper loss, stator iron loss and mechanical loss data by looking up the table using the motor design parameters and test data.

[0143] S222: Based on the motor parameters, obtain the thermal resistance of the motor when it is working.

[0144] Among them, motor parameters refer to the basic indicators of the motor's own design and performance. Different motor parameters will affect the temperature of the motor during operation. Motor parameters include motor slot insulation thickness, motor insulation equivalent thermal conductivity, motor slot inner surface area, core length, thermal conductivity of core, air, and base material, stator slot bottom radius, stator outer radius and base air duct inner radius, equivalent air gap thickness, surface convection exchange heat coefficient, air duct surface area, etc. Different motors have different motor parameters, resulting in different heat generation.

[0145] The thermal resistance of the motor when it is working includes: insulation thermal resistance R Cu-core 、Air duct surface thermal resistance R core-flu and convection heat transfer resistance R conve .

[0146] The insulation thermal resistance is generated by the insulating material between the motor's conductors and the stator core. The insulating material includes conductor paint, insulating paper and potted insulating varnish. The equivalent thermal conductivity of the insulating material is low, resulting in thermal resistance during heat conduction.

[0147] The thermal resistance of the air duct surface is caused by the different heat transfer capabilities between the fluid and the solid surface. It involves the process of heat transfer from the inside of the motor to the air duct surface. That is, the heat is transferred from the casing to the air duct surface, and then the heat is transferred to the air through convection.

[0148] Convective exchange thermal resistance refers to the thermal resistance when the motor surface exchanges heat with the surrounding air through convection. It involves the heat on the motor surface being transferred to the air through convection. The convection exchange thermal resistance is a heat exchange phenomenon caused by the temperature difference between the fluid and the solid surface through which the fluid flows.

[0149] S223: Obtain the motor temperature based on the stator copper loss, the stator iron loss, the mechanical loss data, the thermal resistance of the motor when it is working, and the external environment temperature.

[0150] Specifically, based on the stator copper loss, stator iron loss, mechanical loss data and the heat resistance of the motor when it is working, the stator core temperature rise and the winding copper conductor temperature rise are obtained. The motor temperature is obtained from the stator core temperature rise, the winding copper conductor temperature rise and the external environment temperature.

[0151] In this embodiment, the stator copper loss, stator iron loss and mechanical loss of the motor are obtained based on the motor load and motor speed information, the thermal resistance of the motor when it is working is obtained based on the motor parameters, and the motor temperature is obtained based on the stator copper loss, stator iron loss, mechanical loss data, the thermal resistance of the motor when it is working and the external ambient temperature. This realizes the determination of the motor temperature based on the motor parameters, motor load, motor speed information and external ambient temperature, improves the reliability of obtaining the motor temperature, and provides a basis for cooling the motor when the motor temperature is too high.

[0152] Figure 4 A flow chart of another method for determining the motor temperature of a vehicle provided in an embodiment of the present application is shown as follows: Figure 4 As shown, Figure 4 is Figure 3 On the basis of the illustrated embodiment, further, a possible implementation manner of S222 is as follows:

[0153] S2221: The insulation thermal resistance is obtained based on the motor slot insulation thickness, the motor insulation equivalent thermal conductivity and the inner surface area of ​​the motor slot.

[0154] Specifically, the insulation thermal resistance R Cu-core It can be obtained by the following formula: R Cu-core =δ / (λ insu *Aslot )

[0155]

[0156] Among them, δ is the insulation thickness of the electrodeposition tank, λ insu A is the equivalent thermal conductivity of the electrolytic cell insulation, slot is the inner surface area of ​​the motor slot.

[0157] S2222: The duct surface thermal resistance is obtained based on the core length, the thermal conductivity of the core, the thermal conductivity of the air, the thermal conductivity of the base material, the stator slot bottom radius, the stator outer radius, the base duct inner radius and the equivalent air gap thickness.

[0158] Duct surface thermal resistance R core-flu It is the thermal resistance from the stator core to the surface of the air duct of the machine base, including the conduction thermal resistance from the core node to the outer circle of the stator, the contact thermal resistance between the stator and the machine base, and the conduction thermal resistance from the inner circle of the machine base to the surface of the air duct.

[0159] Among them, the core node refers to the connection point inside the stator core. The loss at the node is concentrated at the copper bar node, which can generate heat. The stator outer circle is the outermost circle of the stator core. The heat needs to be transferred from the core node to the stator outer circle, and then further transferred to the base. The contact thermal resistance between the stator and the base is the process of heat transfer from the stator outer circle to the base inner circle.

[0160] The calculation formula of the duct surface thermal resistance is as follows:

[0161]

[0162] Where l is the core length, λ core is the thermal conductivity of the core, λ air is the thermal conductivity of air, λ base is the thermal conductivity of the base material, r1 is the radius of the stator slot bottom, r2 is the outer radius of the stator, r3 is the inner radius of the base air duct, δ air is the equivalent air gap thickness.

[0163] S2223: The convection exchange thermal resistance is obtained based on the surface convection exchange thermal coefficient and the duct surface area.

[0164] Specifically, the convection heat transfer resistance R conve It can be obtained by the following formula:

[0165]

[0166] Among them, λ flu is the surface convection heat exchange coefficient, that is, the convection heat exchange coefficient between the flowing air and the wall of the duct. The convection heat exchange coefficient of the motor surface can be obtained by looking up the table according to the collected vehicle speed signal. windis the duct surface area.

[0167] S2224: The heat generation thermal resistance of the motor when it is working is obtained based on the insulation thermal resistance, the duct surface thermal resistance and the convection exchange thermal resistance.

[0168] Specifically, the sum of the insulation heat conduction thermal resistance, the air duct surface thermal resistance and the convection exchange thermal resistance is determined as the heat generation thermal resistance when the motor is working.

[0169] In this embodiment, the insulation thermal conductivity thermal resistance is obtained based on the insulation thickness of the motor slot, the equivalent thermal conductivity of the motor insulation and the inner surface area of ​​the motor slot; the duct surface thermal resistance is obtained based on the core length, the thermal conductivity of the core, the thermal conductivity of the air, the thermal conductivity of the base material, the stator slot bottom radius, the stator outer radius, the inner radius of the base air duct and the equivalent air gap thickness; the convection exchange thermal resistance is obtained based on the surface convection exchange heat coefficient and the surface area of ​​the duct; the heating thermal resistance of the motor when it is working is obtained based on the insulation thermal conductivity thermal resistance, the duct surface thermal resistance and the convection exchange thermal resistance, thereby realizing the acquisition of the heat generated by the motor itself when it is working, providing a basis for obtaining the motor temperature, and the calculation of the heating thermal resistance of the motor when it is working is obtained based on the motor's own parameters, motor load and motor speed information, without relying on additional sensors, thereby improving the reliability of the motor temperature calculation.

[0170] Figure 5 A flow chart of another method for determining the motor temperature of a vehicle provided in an embodiment of the present application is shown as follows: Figure 5 As shown, Figure 5 is Figure 3 On the basis of the illustrated embodiment, further, a possible implementation manner of S223 is as follows:

[0171] S2231: Based on the stator copper loss, stator iron loss, and mechanical loss data, the copper loss power value and iron loss power value of the motor when it is working are obtained.

[0172] Among them, the copper loss power value refers to the loss caused by the wire resistance when the current passes through the motor winding. Copper loss will cause the motor to heat up. Excessive loss may cause the motor winding temperature to be too high, causing the insulation material to be affected, thus affecting the motor performance.

[0173] Iron loss power value refers to the loss in the motor core caused by the alternating magnetic field, including hysteresis loss and eddy current loss. Iron loss will cause heat to be generated inside the motor, thus affecting the motor temperature. Excessive motor loss may cause the motor winding temperature to be too high, causing the insulation material to be affected, thus affecting the motor performance.

[0174] Specifically, the copper power consumption value P Cu =Equal to the stator copper loss obtained from the above table; the iron loss power value is equal to half of the sum of the stator iron loss and mechanical loss. The iron loss power value P FeThe calculation formula is as follows:

[0175]

[0176] S2232: Based on the copper loss power value, iron loss power value and thermal resistance of the motor when it is working, the temperature rise of the stator core and the temperature rise of the winding copper conductor are obtained.

[0177] Specifically, the calculation formula for the stator core temperature rise is:

[0178] T Fe =(P Cu +P Fe )*(R core-flu +R conve )

[0179] Among them, P Cu is the copper power consumption value, P Fe is the iron loss power value, R core-flu is the thermal resistance of the duct surface, R conve is the convection thermal resistance.

[0180] The calculation formula for the temperature rise of the winding copper conductor is:

[0181] T Cu =P Cu *R Cu-core +(P Cu +P Fe )*(R core-flu +R conve )

[0182] Among them, P Cu is the copper power consumption value, P Fe is the iron loss power value, R core-flu is the thermal resistance of the duct surface, R conve is the convection heat transfer resistance, R Cu-core is the insulation thermal resistance.

[0183] S2233: The motor temperature is obtained based on the stator core temperature rise, the winding copper conductor temperature rise and the external ambient temperature.

[0184] Specifically, the sum of the temperature rise of the stator core, the temperature rise of the winding copper conductor and the external environment temperature is determined as the motor temperature.

[0185] In this embodiment, the copper loss power value and iron loss power value of the motor when it is working are obtained based on the stator copper loss, the stator iron loss and the mechanical loss data; the stator core temperature rise and the winding copper conductor temperature rise are obtained based on the copper loss power value, the iron loss power value and the heat generation thermal resistance when the motor is working; the motor temperature is obtained based on the stator core temperature rise, the winding copper conductor temperature rise and the external ambient temperature. Thus, the motor temperature of the active stabilizer bar when the motor is working is obtained through the motor parameters, the motor load, the motor speed and the external ambient temperature, which improves the reliability of obtaining the motor temperature. When the motor temperature is at an abnormal operating temperature, it provides a basis for adjusting the working mode of the motor, thereby improving the safety of the vehicle during driving.

[0186] The technical solution of the motor control method of the vehicle is described below with several specific embodiments:

[0187] Figure 6 A flow chart of a motor control method for a vehicle provided in an embodiment of the present application is shown as follows: Figure 6 As shown:

[0188] S61: Determine the motor temperature based on the motor load, motor speed information and external environment temperature.

[0189] The implementation of this step is similar to the implementation of the method for determining the motor temperature of the above-mentioned vehicle, and will not be repeated here.

[0190] S62: Control the motor operating mode based on the motor temperature.

[0191] Set different working modes. Set the working mode of the motor according to the motor temperature. Cool the motor when it is overheated. When the motor temperature returns to normal, set the motor to return to normal working mode.

[0192] In this embodiment, the motor temperature is determined based on the motor load, motor speed information and external ambient temperature, and the working mode of the motor is controlled based on the motor temperature. When the motor is overheated, the motor is cooled to protect the safety of the motor, thereby improving the safety of the vehicle during driving.

[0193] Figure 7 A flow chart of another motor control method for a vehicle provided in an embodiment of the present application is shown as follows: Figure 7 As shown, Figure 7 is Figure 6 On the basis of the illustrated embodiment, further, a possible implementation of S62 is as follows:

[0194] S621: When the motor temperature is greater than or equal to a first preset temperature threshold, based on the steering state of the vehicle or the working state of the active stabilizer bar, the motor is cooled until the motor temperature drops to a second preset temperature threshold.

[0195] One possible way to achieve this is:

[0196] If the steering state of the vehicle is continuous steering, or the working state of the active stabilizer bar is output torque, the rotation speed of the motor is limited until the temperature of the motor drops to a second preset temperature threshold.

[0197] Specifically, if the steering state of the vehicle is continuous steering, or the working state of the active stabilizer bar is output torque, the lower bridge arm of the power tube is controlled to be cut off to achieve a three-phase short circuit to reduce the rotation speed of the motor.

[0198] For example, if the vehicle continues to turn, the motor of the active stabilizer bar still needs to output torque. At this time, the motor is restricted from operating and a preset speed threshold is set. The controller limits the operating speed of the motor to less than the preset speed threshold. The controller cuts off the lower bridge arm of the power tube to achieve a three-phase short circuit. By forming a closed loop, the back electromotive force energy is released, the input voltage is reduced, the current is controlled, and the motor and inverter are protected. The motor speed is reduced. The reduced speed of the motor also reduces the operating current, reducing the heat generated by the motor during operation. At this time, the torque and speed of the motor are both reduced, and the active stabilizer bar is equivalent to a passive stabilizer bar, which only provides linear roll stiffness, which means that the variable stiffness function of the active stabilizer bar is turned off or does not work. The active stabilizer bar is similar to an ordinary passive stabilizer bar, which only provides a fixed linear roll stiffness and is no longer adjusted according to the dynamic needs of the vehicle.

[0199] Another possible way to implement this is:

[0200] If the steering state of the vehicle is no steering, or the working state of the active stabilizer bar is no need to output torque, the motor is powered off until the temperature of the motor drops to a second preset temperature threshold.

[0201] Optionally, the steering angle sensor detects whether the vehicle is turning, and the roll angle and lateral acceleration detected by the roll angle sensor and the lateral acceleration sensor reach a set threshold to determine whether the active stabilizer bar is working. Among them, the steering angle sensor is used to detect whether the vehicle is turning. When the vehicle is turning, the steering angle sensor will detect the rotation of the steering wheel and output a corresponding signal. The roll angle sensor measures the measured roll angle, and the lateral acceleration sensor measures the lateral acceleration of the vehicle when turning.

[0202] The steering angle sensor does not detect the steering wheel rotation, and determines that the active stabilizer bar does not need to work. Alternatively, the roll angle is less than the preset roll angle threshold and the lateral acceleration is less than the preset lateral acceleration threshold, and determines that the active stabilizer bar does not need to work. Alternatively, the steering angle sensor does not detect the steering wheel rotation, the roll angle is less than the preset roll angle threshold and the lateral acceleration is less than the preset lateral acceleration threshold, and determines that the active stabilizer bar does not need to work. At this time, the controller controls the motor to cut off power for cooling.

[0203] For example, the vehicle electronic control unit (ECU) receives signals from a steering angle sensor, a roll angle sensor, and a lateral acceleration sensor, and determines the dynamic state of the vehicle based on the sensor signals. If the steering angle sensor does not detect the steering wheel turning, and the roll angle is less than a preset roll angle threshold and the lateral acceleration is less than a preset lateral acceleration threshold, the ECU determines that the active stabilizer bar does not need to work. When the ECU determines that the active stabilizer bar does not need to work, the ECU sends a control signal of a control motor power-off instruction to the controller of the active stabilizer bar, and the controller controls the pulse width modulation signal to be set to 0 to ensure that the motor does not receive any drive signal, thereby achieving power off.

[0204] When the motor temperature is less than or equal to the second preset temperature threshold, the motor restriction is cancelled and the active stabilizer bar can work normally, which means that the active stabilizer bar can adjust the stability of the vehicle in real time and improve the vehicle's roll stability, ride comfort, handling stability, driving passability, etc.

[0205] Optionally, based on the heat source distribution of the vehicle chassis, the active stabilizer bar can be installed away from the heat source of the chassis. At the same time, air cooling or water cooling can be used, such as a simulated cooling device. When the motor needs to be cooled, the valve of the cooling device is opened, and the motor is cooled by coolant, so that the motor can resume working capacity as soon as possible.

[0206] In the embodiment of the present application, when the temperature of the motor is greater than or equal to the first preset temperature threshold, the motor is cooled based on the steering state of the vehicle or the working state of the active stabilizer bar. If the active stabilizer bar still needs to work, the motor speed is limited to less than the preset speed threshold; if the vehicle has no steering or the active stabilizer bar does not need to work, the motor is controlled to be powered off, and the motor no longer works after the power is off, so no additional heat is generated, and natural cooling is achieved. It is determined that the motor temperature has dropped to the second preset temperature threshold, and the motor restriction is cancelled. By limiting the motor speed when the motor temperature is greater than or equal to the first preset temperature threshold, the motor works at a suitable temperature, reducing the risk of performance degradation or failure caused by high temperature. When the vehicle has no steering or the active stabilizer bar does not need to work, the motor is controlled to be powered off, which can prevent the motor from overheating, thereby protecting the motor from damage, thereby improving the safety of the vehicle during driving, and canceling the restriction on the motor after the motor temperature drops to the second temperature threshold, reducing the restriction on the motor output torque, thereby improving the comfort of the vehicle during driving.

[0207] Figure 8 A flow chart of a method for determining the motor temperature of a vehicle and a method for controlling the motor of the vehicle provided in an embodiment of the present application is provided. Figure 8 It is a combination of the above embodiments. Figure 8 The detailed description of each step can be found in the description of the corresponding steps in the above embodiments, which will not be repeated here.

[0208] Fig. 9 A structural schematic diagram of a motor temperature determination device for a vehicle is provided for an embodiment of the present application, including: an acquisition module 901 and a determination module 902, wherein the acquisition module 901 is used to obtain the motor load, motor speed information and external ambient temperature; the determination module 902 is used to determine the motor temperature based on the motor load, the motor speed information and the external ambient temperature.

[0209] Optionally, the determination module 902 is specifically used to obtain the stator copper loss, stator iron loss and mechanical loss of the motor based on the motor load and motor speed information; obtain the thermal resistance of the motor when it is working based on the motor parameters; and obtain the motor temperature based on the stator copper loss, stator iron loss, mechanical loss data, the thermal resistance of the motor when it is working and the external ambient temperature.

[0210] Optionally, the determination module 902 is specifically used to obtain the insulation thermal conductivity thermal resistance based on the motor slot insulation thickness, the motor insulation equivalent thermal conductivity and the inner surface area of ​​the motor slot; to obtain the duct surface thermal resistance based on the core length, the thermal conductivity of the core, the thermal conductivity of the air, the thermal conductivity of the base material, the stator slot bottom radius, the stator outer radius and the base duct inner radius and the equivalent air gap thickness; to obtain the convection exchange thermal resistance based on the surface convection exchange thermal coefficient and the duct surface area; and to obtain the heat generation thermal resistance of the motor when it is working based on the insulation thermal conductivity thermal resistance, the duct surface thermal resistance and the convection exchange thermal resistance.

[0211] Optionally, the determination module 902 is specifically used to determine that the sum of the insulation heat conduction thermal resistance, the air duct surface thermal resistance and the convection exchange thermal resistance is the heat generation thermal resistance when the motor is working.

[0212] Optionally, the determination module 902 is further configured to obtain insulation thermal resistance based on the motor slot insulation thickness, the motor insulation equivalent thermal conductivity and the motor slot inner surface area, including:

[0213]

[0214] Among them, R Cu-core is the insulation thermal resistance, δ is the insulation thickness of the electroplating tank, λ insu A is the equivalent thermal conductivity of the electrolytic cell insulation, slot is the inner surface area of ​​the motor slot.

[0215] Optionally, the determination module 902 is further used to obtain the duct surface thermal resistance based on the core length, the thermal conductivity of the core, the thermal conductivity of the air, the thermal conductivity of the base material, the stator slot bottom radius, the stator outer radius, the base duct inner radius, and the equivalent air gap thickness, including:

[0216]

[0217] Among them, R core-flu is the thermal resistance of the duct surface, l is the core length, λ core is the thermal conductivity of the core, λ air is the thermal conductivity of air, λ base is the thermal conductivity of the base material, r1 is the radius of the stator slot bottom, r2 is the outer radius of the stator, r3 is the inner radius of the base air duct, δ air is the equivalent air gap thickness.

[0218] Optionally, the determination module 902 is further configured to obtain the convection exchange thermal resistance based on the surface convection exchange heat coefficient and the surface area of ​​the air duct, including:

[0219]

[0220] Among them, R conveis the convection heat transfer resistance, λ flu is the surface convection heat transfer coefficient, A wind is the duct surface area.

[0221] Optionally, the determination module 902 is specifically used to obtain the copper loss power value and iron loss power value when the motor is working based on the stator copper loss, stator iron loss, and mechanical loss data; to obtain the stator core temperature rise and the winding copper conductor temperature rise based on the copper loss power value, iron loss power value, and the heating thermal resistance when the motor is working; to obtain the motor temperature based on the stator core temperature rise, the winding copper conductor temperature rise and the external ambient temperature.

[0222] Optionally, the determination module 902 is specifically used to determine that the copper loss power value is equal to the stator copper loss; and the iron loss power value is equal to half of the sum of the stator iron loss and the mechanical loss.

[0223] Optionally, the determining module 902 is specifically configured to: Fe =(P Cu +P Fe )*(R core-flu +R conve ) to obtain the stator core temperature rise, where P Cu is the copper power consumption value, P Fe is the iron loss power value, R core-flu is the thermal resistance of the duct surface, R conve is the convection exchange thermal resistance; based on T Cu =P Cu *R Cu-core +(P Cu +P Fe )*(R core-flu +R conve ) to obtain the temperature rise of the winding copper conductor, where P Cu is the copper power consumption value, P Fe is the iron loss power value, R core-flu is the thermal resistance of the duct surface, R conve is the convection heat transfer resistance, R Cu-core is the insulation thermal resistance.

[0224] Optionally, the determination module 902 is further used to determine the sum of the stator core temperature rise, the winding copper conductor temperature rise and the external ambient temperature as the motor temperature.

[0225] The device of this embodiment can be used to execute the technical solutions of the above-mentioned method embodiments. Its implementation principles and technical effects are similar and will not be repeated here.

[0226] Fig.10A structural schematic diagram of a motor control device for a vehicle is provided for an embodiment of the present application, including: a determination module 1001 and a control module 1002, wherein the determination module 1001 is used to determine the motor temperature based on the motor load, motor speed information and external ambient temperature; the control module 1002 is used to control the working mode of the motor based on the motor temperature.

[0227] Optionally, the control module 1002 is further configured to cool the motor when the motor temperature is greater than or equal to a first preset temperature threshold, based on a steering state of the vehicle or a working state of an active stabilizer bar, until the motor temperature drops to a second preset temperature threshold.

[0228] Optionally, the control module 1002 is specifically used to limit the speed of the motor until the temperature of the motor drops to a second preset temperature threshold if the steering state of the vehicle is continuous steering, or the working state of the active stabilizer bar is output torque; or, if the steering state of the vehicle is no steering, or the working state of the active stabilizer bar is no need to output torque, cut off power to the motor until the temperature of the motor drops to a second preset temperature threshold.

[0229] Optionally, the control module 1002 is also used to control the cutting off of the lower bridge arm of the power tube to achieve a three-phase short circuit to reduce the speed of the motor if the steering state of the vehicle is continuous steering, or the working state of the active stabilizer bar is output torque.

[0230] Optionally, the determination module 1001 is specifically used to obtain the stator copper loss, stator iron loss and mechanical loss of the motor based on the motor load and motor speed information; based on the motor parameters, obtain the thermal resistance of the motor when it is working; based on the stator copper loss, stator iron loss, mechanical loss data, the thermal resistance of the motor when it is working and the external ambient temperature, obtain the motor temperature.

[0231] Optionally, the determination module 1001 is specifically used to obtain the insulation thermal conductivity thermal resistance based on the motor slot insulation thickness, the motor insulation equivalent thermal conductivity and the inner surface area of ​​the motor slot; to obtain the duct surface thermal resistance based on the core length, the thermal conductivity of the core, the thermal conductivity of the air, the thermal conductivity of the base material, the stator slot bottom radius, the stator outer radius and the base duct inner radius and the equivalent air gap thickness; to obtain the convection exchange thermal resistance based on the surface convection exchange thermal coefficient and the duct surface area; and to obtain the heat generation thermal resistance of the motor when it is working based on the insulation thermal conductivity thermal resistance, the duct surface thermal resistance and the convection exchange thermal resistance.

[0232] Optionally, the determination module 1001 is further used to determine that the sum of the insulation heat conduction thermal resistance, the air duct surface thermal resistance and the convection exchange thermal resistance is the heat generation thermal resistance when the motor is working.

[0233] Optionally, the determination module 1001 is specifically used to obtain the copper loss power value and the iron loss power value when the motor is working based on the stator copper loss, the stator iron loss, and the mechanical loss data; to obtain the stator core temperature rise and the winding copper conductor temperature rise based on the copper loss power value, the iron loss power value, and the heating thermal resistance when the motor is working; to obtain the motor temperature based on the stator core temperature rise, the winding copper conductor temperature rise and the external ambient temperature.

[0234] Optionally, the determination module 1001 is specifically used to determine that the copper loss power value is equal to the stator copper loss; and the iron loss power value is equal to half of the sum of the stator iron loss and the mechanical loss.

[0235] Optionally, the determination module 1001 is further used to determine the sum of the stator core temperature rise, the winding copper conductor temperature rise and the external ambient temperature as the motor temperature.

[0236] The device of this embodiment can be used to execute the technical solutions of the above-mentioned method embodiments. Its implementation principles and technical effects are similar and will not be repeated here.

[0237] The present application also provides an electronic device, the electronic device comprising a processor and a memory. The memory stores a program or instruction that can be run on the processor, and when the program or instruction is executed by the processor, the following is achieved: Figures 2 to 5 The motor temperature determination method of the vehicle shown in Figures 6 to 8 The steps of the motor control method of the vehicle are shown.

[0238] The embodiment of the present application further provides a vehicle, the vehicle comprising a processor and a memory, the memory storing a program or instruction that can be run on the processor, the program or instruction being executed by the processor to implement the following Figures 2 to 5 The motor temperature determination method of the vehicle shown in Figures 6 to 8 The steps of the motor control method of the vehicle are shown.

[0239] The embodiment of the present application also provides a computer-readable storage medium, wherein a program or instruction is stored on the computer-readable storage medium, and when the program or instruction is executed by a processor, the following is implemented: Figures 2 to 5 The motor temperature determination method of the vehicle shown in Figures 6 to 8 The steps of the motor control method of the vehicle are shown.

[0240] The present application also provides a computer program product, which, when executed by a processor of a vehicle or a cloud server, implements the following Figures 2 to 5 The motor temperature determination method of the vehicle shown in Figures 6 to 8 The steps of the motor control method of the vehicle are shown.

[0241] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of a computer software product plus a necessary general hardware platform, and of course, can also be implemented by hardware. The computer software product is stored in a storage medium (such as ROM, RAM, disk, CD, etc.), including several instructions to enable a terminal or a network-side device to execute the methods described in each embodiment of the present application.

[0242] The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present application, ordinary technicians in this field can also make many forms of implementation methods without departing from the purpose of the present application and the scope of protection of the claims, and these implementation methods are all within the protection of the present application.

Claims

1. A method for determining the motor temperature of a vehicle, characterized in that: The method comprises: Obtain motor load, motor speed information and external ambient temperature; The motor temperature is determined based on the motor load, the motor speed information and the ambient temperature.

2. The method according to claim 1, characterized in that The step of determining the motor temperature based on the motor load, the motor speed information and the ambient temperature includes: The stator copper loss, stator iron loss and mechanical loss of the motor are obtained based on the motor load and motor speed information; Based on the motor parameters, the thermal resistance of the motor when it is working is obtained; The motor temperature is obtained based on the stator copper loss, stator iron loss, mechanical loss data, thermal resistance when the motor is working, and the external ambient temperature.

3. The method according to claim 2, characterized in that The heat generation thermal resistance of the motor when it is working is obtained based on the motor parameters, including: The insulation thermal resistance is obtained based on the insulation thickness of the motor slot, the equivalent thermal conductivity of the motor insulation and the inner surface area of ​​the motor slot; The duct surface thermal resistance is obtained based on the core length, the thermal conductivity of the core, the thermal conductivity of the air, the thermal conductivity of the base material, the stator slot bottom radius, the stator outer radius, the inner radius of the base duct, and the equivalent air gap thickness; The convection exchange thermal resistance is obtained based on the surface convection exchange heat coefficient and the surface area of ​​the air duct; The heat generation thermal resistance of the motor when it is working is obtained based on the insulation thermal resistance, the duct surface thermal resistance and the convection exchange thermal resistance.

4. The method according to claim 3, characterized in that: The method of obtaining the heat generation thermal resistance of the motor when it is working based on the insulation heat conduction thermal resistance, the air duct surface thermal resistance and the convection exchange thermal resistance includes: The sum of the insulation heat conduction thermal resistance, the air duct surface thermal resistance and the convection exchange thermal resistance is determined as the heat generation thermal resistance when the motor is working.

5. The method according to claim 3, characterized in that: The insulation thermal resistance is obtained based on the insulation thickness of the motor slot, the equivalent thermal conductivity of the motor insulation and the inner surface area of ​​the motor slot, including: Among them, R Cu-core is the insulation thermal resistance, δ is the insulation thickness of the electroplating tank, λ insu A is the equivalent thermal conductivity of the electrolytic cell insulation, slot is the inner surface area of ​​the motor slot.

6. The method according to claim 3, characterized in that The duct surface thermal resistance is obtained based on the core length, the core thermal conductivity, the air thermal conductivity, the base material thermal conductivity, the stator slot bottom radius, the stator outer radius, the base duct inner radius and the equivalent air gap thickness, including: Among them, R core-flu is the thermal resistance of the duct surface, l is the core length, λ core is the thermal conductivity of the core, λ air is the thermal conductivity of air, λ base is the thermal conductivity of the base material, r1 is the radius of the stator slot bottom, r2 is the outer radius of the stator, r3 is the inner radius of the base air duct, δ air is the equivalent air gap thickness.

7. The method according to claim 3, characterized in that The method of obtaining the convection exchange thermal resistance based on the surface convection exchange thermal coefficient and the surface area of ​​the air duct includes: Among them, R conve is the convection heat transfer resistance, λ flu is the surface convection heat transfer coefficient, A wind is the duct surface area.

8. The method according to claim 2, characterized in that: The motor temperature is obtained based on the stator copper loss, the stator iron loss, the mechanical loss data, the heat resistance of the motor when it is working, and the external environment temperature, including: Based on the stator copper loss, stator iron loss and mechanical loss data, the copper loss power value and iron loss power value of the motor when it is working are obtained; The stator core temperature rise and the winding copper conductor temperature rise are obtained based on the copper loss power value, iron loss power value and the heat generation thermal resistance of the motor when the motor is working; The motor temperature is obtained based on the stator core temperature rise, the winding copper conductor temperature rise and the external ambient temperature.

9. The method according to claim 8, characterized in that The copper loss power value and the iron loss power value when the motor is working are obtained based on the stator copper loss, the stator iron loss, and the mechanical loss data, including: The copper loss power value is equal to the stator copper loss; The iron loss power value is equal to half of the sum of the stator iron loss and the mechanical loss.

10. The method according to claim 8, characterized in that The method of obtaining the stator core temperature rise and the winding copper conductor temperature rise based on the copper loss power value, the iron loss power value and the heat generation thermal resistance of the motor when the motor is working includes: Based on T Fe =(P Cu +P Fe )*(R core-flu +R conve ) to obtain the stator core temperature rise, where P Cu is the copper power consumption value, P Fe is the iron loss power value, R core-flu is the thermal resistance of the duct surface, R conve is the convection exchange thermal resistance; Based on T Cu =P Cu *R Cu-core +(P Cu +P Fe )*(R core-flu +R conve ) to obtain the temperature rise of the winding copper conductor, where P Cu is the copper power consumption value, P Fe is the iron loss power value, R core-flu is the thermal resistance of the duct surface, R conve is the convection heat transfer resistance, R Cu-core is the insulation thermal resistance.

11. The method according to claim 8, characterized in that The motor temperature is obtained based on the stator core temperature rise, the winding copper conductor temperature rise and the external environment temperature, including: The sum of the stator core temperature rise, the winding copper conductor temperature rise and the external environment temperature is determined as the motor temperature.

12. A motor control method for a vehicle, characterized in that: The method comprises: Determine the motor temperature based on the motor load, motor speed information and the ambient temperature; An operating mode of the motor is controlled based on the motor temperature.

13. The method according to claim 12, characterized in that The method of controlling the working mode of the motor based on the motor temperature includes: When the temperature of the motor is greater than or equal to a first preset temperature threshold, the motor is cooled based on a steering state of a vehicle or a working state of an active stabilizer bar until the temperature of the motor is reduced to a second preset temperature threshold.

14. The method according to claim 13, characterized in that The step of cooling the motor based on the steering state of the vehicle or the working state of the active stabilizer bar until the temperature of the motor drops to a second preset temperature threshold comprises: If the steering state of the vehicle is continuous steering, or the working state of the active stabilizer bar is output torque, limiting the speed of the motor until the temperature of the motor decreases to a second preset temperature threshold; or, If the steering state of the vehicle is no steering, or the working state of the active stabilizer bar is no need to output torque, the motor is powered off until the temperature of the motor drops to a second preset temperature threshold.

15. The method according to claim 14, characterized in that If the steering state of the vehicle is continuous steering, or the working state of the active stabilizer bar is output torque, limiting the speed of the motor until the temperature of the motor drops to a second preset temperature threshold, including: If the steering state of the vehicle is continuous steering, or the working state of the active stabilizer bar is output torque, the lower bridge arm of the power tube is controlled to be cut off to achieve a three-phase short circuit to reduce the rotation speed of the motor.

16. The method according to any one of claims 12 to 15, characterized in that: The step of determining the motor temperature based on the motor load, the motor speed information and the ambient temperature includes: The stator copper loss, stator iron loss and mechanical loss of the motor are obtained based on the motor load and motor speed information; Based on the motor parameters, the thermal resistance of the motor when it is working is obtained; The motor temperature is obtained based on the stator copper loss, stator iron loss, mechanical loss data, thermal resistance when the motor is working, and the external ambient temperature.

17. The method according to claim 16, characterized in that The heat generation thermal resistance of the motor when it is working is obtained based on the motor parameters, including: The insulation thermal resistance is obtained based on the insulation thickness of the motor slot, the equivalent thermal conductivity of the motor insulation and the inner surface area of ​​the motor slot; The duct surface thermal resistance is obtained based on the core length, the thermal conductivity of the core, the thermal conductivity of the air, the thermal conductivity of the base material, the stator slot bottom radius, the stator outer radius, the inner radius of the base duct, and the equivalent air gap thickness; The convection exchange thermal resistance is obtained based on the surface convection exchange heat coefficient and the surface area of ​​the air duct; The heat generation thermal resistance of the motor when it is working is obtained based on the insulation thermal resistance, the duct surface thermal resistance and the convection exchange thermal resistance.

18. The method according to claim 17, characterized in that The method of obtaining the heat generation thermal resistance of the motor when it is working based on the insulation heat conduction thermal resistance, the air duct surface thermal resistance and the convection exchange thermal resistance includes: The sum of the insulation heat conduction thermal resistance, the air duct surface thermal resistance and the convection exchange thermal resistance is determined as the heat generation thermal resistance when the motor is working.

19. The method according to claim 16, characterized in that The motor temperature is obtained based on the stator copper loss, the stator iron loss, the mechanical loss data, the heat resistance of the motor when it is working, and the external environment temperature, including: Based on the stator copper loss, stator iron loss and mechanical loss data, the copper loss power value and iron loss power value of the motor when it is working are obtained; The stator core temperature rise and the winding copper conductor temperature rise are obtained based on the copper loss power value, iron loss power value and the heat generation thermal resistance of the motor when the motor is working; The motor temperature is obtained based on the stator core temperature rise, the winding copper conductor temperature rise and the external ambient temperature.

20. The method according to claim 19, characterized in that The copper loss power value and the iron loss power value when the motor is working are obtained based on the stator copper loss, the stator iron loss, and the mechanical loss data, including: The copper loss power value is equal to the stator copper loss; The iron loss power value is equal to half of the sum of the stator iron loss and the mechanical loss.

21. The method according to claim 19, characterized in that The motor temperature is obtained based on the stator core temperature rise, the winding copper conductor temperature rise and the external environment temperature, including: The sum of the stator core temperature rise, the winding copper conductor temperature rise and the external environment temperature is determined as the motor temperature.

22. An electronic device, characterized in that: include: A processor and a memory, wherein the memory stores a program or instruction that can be run on the processor, and when the program or instruction is executed by the processor, the method for determining the motor temperature of a vehicle as described in any one of claims 1 to 11 or the method for controlling the motor of a vehicle as described in claims 12-21 is implemented.

23. A vehicle, characterized in that: include: A processor and a memory, wherein the memory stores a program or instruction that can be run on the processor, and when the program or instruction is executed by the processor, the method for determining the motor temperature of a vehicle as described in any one of claims 1 to 11 or the method for controlling the motor of a vehicle as described in claims 12-21 is implemented.

24. A computer-readable storage medium, characterized in that: The readable storage medium stores a program or an instruction, and when the program or the instruction is executed by the processor, the method for determining the motor temperature of a vehicle according to any one of claims 1 to 11 or the method for controlling the motor of a vehicle according to claims 12-21 is implemented.

25. A computer program product, characterized in that When the program product is executed by a processor of a vehicle or a cloud server, it implements the motor temperature determination method of a vehicle as described in any one of claims 1 to 11 or the motor control method of a vehicle as described in claims 12-21.

Images