Motor torque control method and device, hybrid vehicle torque control method

Abstract

The present application provides a motor torque control method and device, and a hybrid vehicle torque control method, the method comprising: finding the motor rated torque corresponding to the motor's required speed; if the motor's required torque is less than or equal to the motor's rated torque, controlling the motor's output torque to be equal to the motor's required torque; if the motor's required torque is greater than the motor's rated torque and the motor's real-time temperature is less than or equal to a reduction threshold, controlling the motor's output torque to be equal to the motor's required torque; if the motor's required torque is greater than the motor's rated torque and the motor's real-time temperature is less than a temperature protection threshold but greater than a reduction threshold, controlling the motor's output torque to be between zero and the motor's required torque, wherein the closer the motor's real-time temperature is to the reduction threshold, the closer the motor's output torque is to the motor's required torque, and the closer the motor's real-time temperature is to the temperature protection threshold, the closer the motor's output torque is to zero. Through the present application, torque requirements can be met as much as possible while avoiding forced power-off triggered by motor overheating.

Description

Technical Field

[0001] The present application relates to the field of motor control technology, and in particular to a motor torque control method and device, and a hybrid vehicle torque control method. Background Art

[0002] As a key power output component, motors play a vital role in numerous industrial, transportation, and electromechanical equipment applications. Accurately controlling motor torque has a profound impact on the equipment's normal operation, performance, and service life.

[0003] Traditional motor torque control methods typically employ a straightforward approach, assuming the motor's output torque equals the required torque. However, in practical applications, sudden increases in the motor's required torque often occur. This excessive torque can lead to serious problems. When the motor outputs high torque, its internal current increases significantly, generating significant heat in the motor windings and causing the motor temperature to rise continuously.

[0004] Currently, most motors are equipped with overheat protection mechanisms. When the motor temperature reaches a preset threshold, the system forcibly disconnects the motor to prevent irreversible damage from overheating, such as insulation damage and winding short circuits. While this forced power-off protects the motor's hardware, it can cause significant inconvenience and adverse effects on the entire device or system.

[0005] Therefore, when faced with the situation where the motor torque demand is too large, the traditional motor torque control method has the defect of triggering forced power off due to motor overheating, affecting the normal operation of the equipment and bringing many potential risks. A more reasonable and effective motor torque control method is urgently needed to solve the above problems. Summary of the Invention

[0006] The present application provides a motor torque control method and device, and a hybrid vehicle torque control method, which can solve the technical problem in the prior art of forced power off triggered by motor overheating.

[0007] In a first aspect, an embodiment of the present application provides a motor torque control method, the motor torque control method comprising:

[0008] Find the motor rated torque corresponding to the required motor speed on the motor external characteristic curve;

[0009] If the motor's required torque is less than or equal to the motor's rated torque, the motor's output torque is controlled to be equal to the motor's required torque;

[0010] If the motor demand torque is greater than the motor rated torque and the motor real-time temperature is less than or equal to the reduction threshold, the motor output torque is controlled to be equal to the motor demand torque, wherein the reduction threshold is less than the temperature protection threshold;

[0011] If the motor demand torque is greater than the motor rated torque, and the motor real-time temperature is less than the temperature protection threshold but greater than the reduction threshold, the motor output torque is controlled between zero and the motor demand torque. The closer the motor real-time temperature is to the reduction threshold, the closer the motor output torque is to the motor demand torque, and the closer the motor real-time temperature is to the temperature protection threshold, the closer the motor output torque is to zero.

[0012] Furthermore, in one embodiment, the reduction threshold is greater than or equal to the equilibrium temperature of the motor when the motor operates at the required speed and rated torque of the motor.

[0013] Furthermore, in one embodiment, the step of controlling the motor output torque to be between zero and the motor required torque includes:

[0014] The output torque of the controlled motor is equal to the product of the motor demand torque and the reduction coefficient. The calculation formula of the reduction coefficient is:

[0015]

[0016] Among them, k represents the reduction coefficient, T i Indicates the real-time temperature of the motor, T e represents the equilibrium temperature, T LIM Indicates the temperature protection threshold.

[0017] Furthermore, in one embodiment, the motor torque control method is applied to a hybrid electric vehicle with a P2 architecture;

[0018] When the clutch between the engine and the motor is in the engaged state, and the required torque and speed of the drive axle wheel end fall outside the engine's economic output band, the motor's required speed is equal to the required speed of the drive axle wheel end, and the motor's required torque is equal to the difference between the required torque of the drive axle wheel end and the engine's optimal torque;

[0019] The optimal engine torque is the torque corresponding to the required speed of the drive axle wheel end on the engine economy optimal curve.

[0020] Furthermore, in one embodiment, when the clutch between the engine and the motor is in the engaged state and the required torque and speed of the drive axle wheel end fall within the economic output band of the engine, the required speed of the motor is equal to the required speed of the drive axle wheel end, and the required torque of the motor is zero.

[0021] Furthermore, in one embodiment, when the clutch between the engine and the motor is in a disconnected state, the motor required speed is equal to the drive axle wheel end required speed, and the motor required torque is equal to the drive axle wheel end required torque.

[0022] In a second aspect, an embodiment of the present application further provides a hybrid vehicle torque control method, which is applied to a hybrid vehicle with a P2 architecture. The hybrid vehicle torque control method includes:

[0023] When the clutch between the engine and the motor is in the engaged state, check whether the required torque and speed of the drive axle wheel end are within the economic output band of the engine;

[0024] If the required torque and speed of the drive axle wheel end fall outside the engine economic output band, the optimal engine torque corresponding to the required speed of the drive axle wheel end is found on the engine economic optimal curve;

[0025] Set the motor required speed to be equal to the drive axle wheel end required speed, and the motor required torque to be equal to the difference between the drive axle wheel end required torque and the engine optimal torque, and execute the steps of the motor torque control method described above;

[0026] The engine output torque is controlled to be equal to the difference between the engine optimal torque or the required torque at the drive axle wheel end and the motor output torque.

[0027] Furthermore, in one embodiment, after the step of checking whether the required torque and speed of the drive axle wheel end fall within the economic output band of the engine, the method further includes:

[0028] If the drive axle wheel end required torque and the drive axle wheel end required speed fall within the engine economic output band, the engine output torque is controlled to be equal to the drive axle wheel end required torque, and the motor output torque is controlled to be equal to zero.

[0029] Furthermore, in one embodiment, the hybrid vehicle torque control method further includes:

[0030] When the clutch between the engine and the motor is in the engaged state, the motor required speed is equal to the drive axle wheel end required speed, and the motor required torque is equal to the drive axle wheel end required torque, and the steps of the motor torque control method are executed.

[0031] In a second aspect, an embodiment of the present application further provides a motor torque control device, the motor torque control device comprising:

[0032] Rated search module, used to find the motor rated torque corresponding to the motor required speed on the motor external characteristic curve;

[0033] A first output module, configured to control the motor output torque to be equal to the motor demand torque if the motor demand torque is less than or equal to the motor rated torque;

[0034] A second output module is configured to control the motor output torque to be equal to the motor demand torque if the motor demand torque is greater than the motor rated torque and the motor real-time temperature is less than or equal to a reduction threshold, wherein the reduction threshold is less than a temperature protection threshold;

[0035] The third output module is used to control the motor output torque between zero and the motor required torque if the motor required torque is greater than the motor rated torque, and the motor real-time temperature is less than the temperature protection threshold and greater than the reduction threshold, wherein the closer the motor real-time temperature is to the reduction threshold, the closer the motor output torque is to the motor required torque, and the closer the motor real-time temperature is to the temperature protection threshold, the closer the motor output torque is to zero.

[0036] In this application, the motor demand torque and the motor rated torque are first compared. When the motor demand torque is not higher than the motor rated torque, the motor output torque is controlled to be equal to the motor demand torque. When the motor demand torque is higher, the motor real-time temperature and the reduction threshold are further compared. When the motor real-time temperature is not higher than the reduction threshold, the motor output torque is controlled to be equal to the motor demand torque. When the motor real-time temperature is higher than the reduction threshold, the motor output torque is controlled between zero and the motor demand torque. The closer the motor real-time temperature is to the reduction threshold, the closer the motor output torque is to the motor demand torque. While delaying the temperature rise, the torque demand is met as much as possible. The closer the motor real-time temperature is to the temperature protection threshold, the closer the motor output torque is to zero, so as to reduce the motor temperature as quickly as possible and avoid the motor temperature reaching the temperature protection threshold. Through this application, the torque demand can be met as much as possible while avoiding the motor overheating and triggering a forced power off, thereby improving the stability of equipment operation and reducing adverse effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 Schematic diagram of a flow chart of a motor torque control method according to an embodiment of the present application;

[0038] Figure 2 A schematic diagram of the drive system of a hybrid vehicle with a P2 architecture;

[0039] Figure 3 This is a flow chart of a method for controlling torque of a hybrid vehicle according to an embodiment of the present application;

[0040] Figure 4 Schematic diagram of the functional modules of a motor torque control device in one embodiment of the present application. DETAILED DESCRIPTION

[0041] In order to enable those skilled in the art to better understand the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0042] In order to make the objectives, technical solutions and advantages of this application clearer, the implementation methods of this application will be further described in detail below with reference to the accompanying drawings.

[0043] In a first aspect, an embodiment of the present application provides a motor torque control method.

[0044] Figure 1 A flow chart of a motor torque control method in an embodiment of the present application is shown.

[0045] Reference Figure 1 In one embodiment, the motor torque control method includes the following steps:

[0046] S11. Find the motor rated torque corresponding to the required motor speed on the motor external characteristic curve.

[0047] Specifically, when the motor operates under rated operating conditions, there is a specific relationship between the motor torque and the motor speed, which is described by the motor external characteristic curve.

[0048] For example, the abscissa of the motor characteristic curve is the motor speed, and the ordinate is the motor torque. The ordinate corresponding to the point on the motor characteristic curve where the abscissa is equal to the motor required speed is the rated torque of the motor described in this embodiment.

[0049] S12. If the motor required torque is less than or equal to the motor rated torque, control the motor output torque to be equal to the motor required torque.

[0050] Specifically, when the motor required torque is less than or equal to the motor rated torque, there is no risk of overheating of the motor, and the motor output torque is controlled to be equal to the motor required torque to normally meet the torque demand.

[0051] S13. If the motor demand torque is greater than the motor rated torque and the motor real-time temperature is less than or equal to the reduction threshold, control the motor output torque to be equal to the motor demand torque, wherein the reduction threshold is less than the temperature protection threshold.

[0052] Specifically, when the required torque of the motor is greater than the rated torque of the motor, the real-time temperature of the motor is added as a judgment basis, and a certain margin is retained between the reduction threshold and the temperature protection threshold. When the real-time temperature of the motor is less than or equal to the reduction threshold, the motor does not have the risk of overheating in a short period of time, and the output torque of the motor is controlled to be equal to the required torque of the motor, so that the torque demand is normally met.

[0053] S14. If the motor demand torque is greater than the motor rated torque, and the motor real-time temperature is less than the temperature protection threshold but greater than the reduction threshold, the motor output torque is controlled between zero and the motor demand torque, wherein the closer the motor real-time temperature is to the reduction threshold, the closer the motor output torque is to the motor demand torque, and the closer the motor real-time temperature is to the temperature protection threshold, the closer the motor output torque is to zero.

[0054] Specifically, when the real-time temperature of the motor is greater than the reduction threshold, the motor is at risk of overheating in a short period of time, and the motor output torque needs to be reduced and controlled between zero and the motor required torque. The closer the real-time temperature of the motor is to the reduction threshold, the closer the motor output torque is to the motor required torque, and the torque demand is met as much as possible while delaying the temperature rise. The closer the real-time temperature of the motor is to the temperature protection threshold, the closer the motor output torque is to zero, so as to reduce the motor temperature as soon as possible to avoid the motor temperature reaching the temperature protection threshold and the motor overheating triggering forced power off.

[0055] It should be noted that in all the above cases, the motor output speed is equal to the motor required speed.

[0056] It should be noted that when the motor output torque is less than the motor required torque, for the entire device, if there is no other power source to make up for the missing part, there will be a temporary performance decline. However, in the long run, the performance of the device under the control of this scheme is better than that of the device under the control of the traditional scheme.

[0057] For example, assuming the motor's required torque is continuously greater than its rated torque, if motor torque control is performed using a traditional solution, the motor's output torque equals the motor's required torque. After 10 minutes of operation, the motor's real-time temperature rises to the temperature protection threshold, triggering a forced power outage. Power is restored 10 minutes after the motor is powered off. If motor torque control is performed using this solution, within 1-5 minutes, the motor's output torque equals the motor's required torque, and the motor's real-time temperature rises to the reduction threshold. Within 6-10 minutes, the motor's output torque gradually decreases, and the motor's real-time temperature first slowly rises to near the temperature protection threshold, then rapidly decreases to below the reduction threshold. Within 11-15 minutes, the motor's output torque equals the motor's required torque, and the motor's real-time temperature rises to the reduction threshold. Within 16-20 minutes, the motor's output torque gradually decreases, and the motor's real-time temperature first slowly rises to near the temperature protection threshold, then rapidly decreases to below the reduction threshold. Within the first 10 minutes, the average motor output torque of this solution is lower than that of the traditional solution. Over the entire 20 minutes, the average motor output torque of this solution is higher than that of the traditional solution.

[0058] Therefore, through this embodiment, the torque demand can be met as much as possible without triggering forced power off due to motor overheating, thereby improving the operating stability of the equipment and reducing adverse effects.

[0059] Furthermore, in one embodiment, the reduction threshold is greater than or equal to the equilibrium temperature of the motor when the motor operates at the required speed and rated torque of the motor.

[0060] In this embodiment, the equilibrium temperature of the motor when it runs at the required motor speed and rated motor torque is a fixed value that can be measured in advance. Using it as the basis for setting the reduction threshold helps to improve the effect of motor torque control.

[0061] Furthermore, in one embodiment, the step of controlling the motor output torque to be between zero and the motor required torque includes:

[0062] The output torque of the controlled motor is equal to the product of the motor demand torque and the reduction coefficient. The calculation formula of the reduction coefficient is:

[0063]

[0064] Among them, k represents the reduction coefficient, T i Indicates the real-time temperature of the motor, T e represents the equilibrium temperature, T LIM Indicates the temperature protection threshold.

[0065] Specifically, T LIM -T e (referred to as the denominator) is a constant, T i -T e(referred to as the numerator) is greater than zero, T i The closer to T LIM , the closer the ratio of the numerator to the denominator is to 1, the closer k is to 0, and the closer the product of the motor demand torque and the reduction coefficient is to zero, T i The closer to T e , the closer the ratio of the numerator to the denominator is to 0, the closer k is to 1, and the closer the product of the motor demand torque and the reduction coefficient is to the motor demand torque.

[0066] In this embodiment, a specific reduction strategy for the motor output torque is provided. The calculation formula of the reduction coefficient k is obtained based on a large amount of test data fitting. Under the premise of avoiding motor overheating and triggering forced power off, the motor output torque can be further improved.

[0067] Furthermore, in one embodiment, the motor torque control method is applied to a hybrid electric vehicle with a P2 architecture;

[0068] When the clutch between the engine and the motor is in the engaged state, and the required torque and speed of the drive axle wheel end fall outside the engine's economic output band, the motor's required speed is equal to the required speed of the drive axle wheel end, and the motor's required torque is equal to the difference between the required torque of the drive axle wheel end and the engine's optimal torque;

[0069] The optimal engine torque is the torque corresponding to the required speed of the drive axle wheel end on the engine economy optimal curve.

[0070] Figure 2 A schematic diagram of the drive system of a hybrid vehicle with a P2 architecture is shown.

[0071] Reference Figure 2 The drive system of a P2-based hybrid vehicle includes the engine, clutch, drive motor, multi-speed transmission, HCU (Hybrid Control Unit), MCU (Motor Control Unit), EOP (Clutch Control Unit), and drive axle. When the clutch between the engine and motor is engaged, the engine and drive motor jointly provide torque to the drive axle, defining this as hybrid mode. When the clutch between the engine and motor is disengaged, only the drive motor provides torque to the drive axle, defining this as pure electric mode.

[0072] Specifically, after the vehicle enters the READY state, hybrid mode is selected using the mode select button. The HCU engages the clutch via the EOP (Electric Power Controller Unit). The HCU checks whether the required drive axle wheel-end torque and speed fall within the engine's economic output band. If they do, the drive motor must shoulder some of the torque demand to optimize engine fuel consumption. The HCU searches the engine's economic optimization curve for the optimal engine torque corresponding to the required drive axle wheel-end speed. The HCU then sets the motor's required speed equal to the required drive axle wheel-end speed and the motor's required torque equal to the difference between the required drive axle wheel-end torque and the optimal engine torque. Steps S11 through S14 are then executed, and the resulting motor output torque is sent to the MCU.

[0073] Specifically, when the engine operates at optimal fuel consumption, there is a specific relationship between engine torque and engine speed, which is described by the engine economy optimal curve. The engine economic output band is an area including the engine economy optimal curve. The width is defined according to demand, indicating an operating state with better fuel consumption.

[0074] For example, the engine economy optimization curve has an abscissa that represents engine speed and an ordinate that represents engine torque. To determine whether the required drive axle wheel-end torque and required drive axle wheel-end speed fall within the engine's economic output band, the point with the required drive axle wheel-end torque on the ordinate and the required drive axle wheel-end speed on the abscissa is found, and then the point's ordinate is determined to represent the required drive axle wheel-end speed. The point on the engine economy optimization curve where the abscissa is equal to the required drive axle wheel-end speed represents the optimal engine torque in this embodiment.

[0075] Furthermore, in one embodiment, when the clutch between the engine and the motor is in the engaged state and the required torque and speed of the drive axle wheel end fall within the economic output band of the engine, the required speed of the motor is equal to the required speed of the drive axle wheel end, and the required torque of the motor is zero.

[0076] Specifically, when the HCU finds that the required torque and speed of the drive axle wheel end fall within the economic output band of the engine, the engine can bear all torque requirements with better fuel consumption, making the required motor speed equal to the required speed of the drive axle wheel end, and making the required motor torque equal to zero, executing steps S11 to S14, and sending the obtained motor output torque to the MCU. It can be understood that the obtained motor output torque is also zero.

[0077] Furthermore, in one embodiment, when the clutch between the engine and the motor is in a disconnected state, the motor required speed is equal to the drive axle wheel end required speed, and the motor required torque is equal to the drive axle wheel end required torque.

[0078] Specifically, after the vehicle enters the READY state, the pure electric mode is selected through the mode selection button, and the HCU uses EOP to disengage the clutch, making the motor's required speed equal to the drive axle wheel end's required speed, and the motor's required torque equal to the drive axle wheel end's required torque. Steps S11 to S14 are executed, and the obtained motor output torque is sent to the MCU.

[0079] It should be noted that the above embodiments are only examples of application scenarios of this solution. This solution can also be applied in other scenarios, such as pure electric vehicles and other equipment using motors.

[0080] In a second aspect, an embodiment of the present application further provides a hybrid vehicle torque control method, which is applied to a hybrid vehicle with a P2 architecture.

[0081] Figure 3 A flow chart of a hybrid vehicle torque control method according to an embodiment of the present application is shown.

[0082] Reference Figures 1 to 3 In one embodiment, a method for controlling torque of a hybrid vehicle includes the following steps:

[0083] S21. When the clutch between the engine and the motor is engaged, check whether the required torque and speed at the drive axle wheel end are within the economic output band of the engine.

[0084] S22. If the required drive axle wheel end torque and the required drive axle wheel end speed fall outside the engine economic output band, searching for the engine optimal torque corresponding to the required drive axle wheel end speed on the engine economic optimal curve;

[0085] S23, setting the motor required speed to be equal to the drive axle wheel end required speed, and the motor required torque to be equal to the difference between the drive axle wheel end required torque and the engine optimal torque, and executing steps S11 to S14;

[0086] S24. Control the engine output torque to be equal to the optimal engine torque or the difference between the drive axle wheel end required torque and the motor output torque.

[0087] In this embodiment, if the engine output torque is controlled to be equal to the optimal engine torque, the engine can operate with optimal fuel consumption. However, when the motor output torque is less than the motor required torque, the torque transmitted to the drive axle wheel end is lower than the drive axle wheel end required torque, resulting in the actual vehicle speed of the hybrid vehicle being lower than the target vehicle speed.

[0088] If the engine output torque is controlled to be equal to the difference between the required torque at the drive axle wheel end and the motor output torque, then when the motor output torque is less than the motor required torque, the engine will make up for the missing part at the expense of fuel consumption, so that the torque transmitted to the drive axle wheel end is equal to the required torque at the drive axle wheel end, ensuring that the actual vehicle speed of the hybrid vehicle is equal to the target vehicle speed.

[0089] Furthermore, in one embodiment, after the step of checking whether the required torque and speed of the drive axle wheel end fall within the economic output band of the engine, the method further includes:

[0090] If the drive axle wheel end required torque and the drive axle wheel end required speed fall within the engine economic output band, the engine output torque is controlled to be equal to the drive axle wheel end required torque, and the motor output torque is controlled to be equal to zero.

[0091] Furthermore, in one embodiment, the hybrid vehicle torque control method further includes:

[0092] When the clutch between the engine and the motor is in the engaged state, the motor required speed is equal to the drive axle wheel end required speed, and the motor required torque is equal to the drive axle wheel end required torque, and steps S11 to S14 are executed.

[0093] In a third aspect, an embodiment of the present application also provides a motor torque control device.

[0094] Figure 4 A schematic diagram of the functional modules of a motor torque control device in one embodiment of the present application is shown.

[0095] Reference Figure 4 In one embodiment, the motor torque control device includes:

[0096] The rated search module 10 is used to search the motor rated torque corresponding to the motor required speed on the motor external characteristic curve;

[0097] The first output module 20 is configured to control the motor output torque to be equal to the motor demand torque if the motor demand torque is less than or equal to the motor rated torque;

[0098] The second output module 30 is configured to control the motor output torque to be equal to the motor demand torque if the motor demand torque is greater than the motor rated torque and the motor real-time temperature is less than or equal to a reduction threshold, wherein the reduction threshold is less than a temperature protection threshold;

[0099] The third output module 40 is used to control the motor output torque between zero and the motor required torque if the motor required torque is greater than the motor rated torque, and the motor real-time temperature is less than the temperature protection threshold and greater than the reduction threshold, wherein the closer the motor real-time temperature is to the reduction threshold, the closer the motor output torque is to the motor required torque, and the closer the motor real-time temperature is to the temperature protection threshold, the closer the motor output torque is to zero.

[0100] Furthermore, in one embodiment, the reduction threshold is greater than or equal to the equilibrium temperature of the motor when the motor operates at the required speed and rated torque of the motor.

[0101] Furthermore, in one embodiment, the third output module 40 is used to:

[0102] The output torque of the controlled motor is equal to the product of the motor demand torque and the reduction coefficient. The calculation formula of the reduction coefficient is:

[0103]

[0104] Among them, k represents the reduction coefficient, T i Indicates the real-time temperature of the motor, T e represents the equilibrium temperature, T LIM Indicates the temperature protection threshold.

[0105] Furthermore, in one embodiment, the motor torque control device is applied to a hybrid electric vehicle with a P2 architecture;

[0106] When the clutch between the engine and the motor is in the engaged state, and the required torque and speed of the drive axle wheel end fall outside the engine's economic output band, the motor's required speed is equal to the required speed of the drive axle wheel end, and the motor's required torque is equal to the difference between the required torque of the drive axle wheel end and the engine's optimal torque;

[0107] The optimal engine torque is the torque corresponding to the required speed of the drive axle wheel end on the engine economy optimal curve.

[0108] Furthermore, in one embodiment, when the clutch between the engine and the motor is in the engaged state and the required torque and speed of the drive axle wheel end fall within the economic output band of the engine, the required speed of the motor is equal to the required speed of the drive axle wheel end, and the required torque of the motor is zero.

[0109] Furthermore, in one embodiment, when the clutch between the engine and the motor is in a disconnected state, the motor required speed is equal to the drive axle wheel end required speed, and the motor required torque is equal to the drive axle wheel end required torque.

[0110] Among them, the functional implementation of each module in the above-mentioned motor torque control device corresponds to the various steps in the above-mentioned motor torque control method embodiment, and their functions and implementation processes are no longer repeated here.

[0111] It should be noted that the serial numbers of the above-mentioned embodiments of the present application are for description only and do not represent the advantages or disadvantages of the embodiments.

[0112] The terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned drawings are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally includes steps or units that are not listed, or optionally includes other steps or units inherent to these processes, methods, products or devices. The terms "first", "second" and "third" are used to distinguish different objects, etc., and do not represent a sequence, nor do they limit the "first", "second" and "third" to different types.

[0113] In the description of the embodiments of this application, the words "exemplary," "for example," or "for example" are used to indicate examples, illustrations, or descriptions. Any embodiment or design described as "exemplary," "for example," or "for example" in the embodiments of this application should not be construed as being preferred or advantageous over other embodiments or designs. Rather, the use of words such as "exemplary," "for example," or "for example" is intended to present the relevant concepts in a concrete manner.

[0114] In the description of the embodiments of the present application, unless otherwise specified, “ / ” means or, for example, A / B can mean A or B; “and / or” in the text is merely a description of the association relationship of associated objects, indicating that three relationships may exist, for example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, in the description of the embodiments of the present application, “multiple” refers to two or more than two.

[0115] In some processes described in the embodiments of the present application, multiple operations or steps are included that appear in a specific order. However, it should be understood that these operations or steps may not be performed in the order in which they appear in the embodiments of the present application or may be performed in parallel. The sequence numbers of the operations are only used to distinguish between different operations, and the sequence numbers themselves do not represent any order of execution. In addition, these processes may include more or fewer operations, and these operations or steps may be performed in sequence or in parallel, and these operations or steps may be combined.

[0116] 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 software plus the necessary general hardware platform, of course, it can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, can be embodied in the form of a software product, which is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) as described above, and includes a number of instructions for enabling a terminal device to execute the methods described in each embodiment of the present application.

[0117] The above are only preferred embodiments of the present application and do not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A motor torque control method, characterized in that: The motor torque control method comprises: Find the motor rated torque corresponding to the required motor speed on the motor external characteristic curve; If the motor's required torque is less than or equal to the motor's rated torque, the motor's output torque is controlled to be equal to the motor's required torque; If the motor demand torque is greater than the motor rated torque and the motor real-time temperature is less than or equal to the reduction threshold, the motor output torque is controlled to be equal to the motor demand torque, wherein the reduction threshold is less than the temperature protection threshold; If the motor demand torque is greater than the motor rated torque, and the motor real-time temperature is less than the temperature protection threshold but greater than the reduction threshold, the motor output torque is controlled between zero and the motor demand torque. The closer the motor real-time temperature is to the reduction threshold, the closer the motor output torque is to the motor demand torque, and the closer the motor real-time temperature is to the temperature protection threshold, the closer the motor output torque is to zero.

2. The motor torque control method according to claim 1, wherein: The reduction threshold is greater than or equal to the equilibrium temperature when the motor operates at the required motor speed and the rated motor torque.

3. The motor torque control method according to claim 2, wherein: The step of controlling the motor output torque to be between zero and the motor required torque includes: The output torque of the controlled motor is equal to the product of the motor demand torque and the reduction coefficient. The calculation formula of the reduction coefficient is: Where k represents the reduction coefficient, Indicates the real-time temperature of the motor. represents the equilibrium temperature, Indicates the temperature protection threshold.

4. The motor torque control method according to any one of claims 1 to 3, characterized in that: The motor torque control method is applied to a hybrid electric vehicle with a P2 architecture; When the clutch between the engine and the motor is in the engaged state, and the required torque and speed of the drive axle wheel end fall outside the engine's economic output band, the motor's required speed is equal to the required speed of the drive axle wheel end, and the motor's required torque is equal to the difference between the required torque of the drive axle wheel end and the engine's optimal torque; The optimal engine torque is the torque corresponding to the required speed of the drive axle wheel end on the engine economy optimal curve.

5. The motor torque control method according to claim 4, wherein: When the clutch between the engine and the motor is in the engaged state, and the required torque and speed of the drive axle wheel end fall within the engine's economic output band, the motor's required speed is equal to the drive axle wheel end's required speed, and the motor's required torque is zero.

6. The motor torque control method according to claim 4, wherein: When the clutch between the engine and the motor is in a disconnected state, the motor's required speed is equal to the drive axle wheel end's required speed, and the motor's required torque is equal to the drive axle wheel end's required torque.

7. A method for controlling torque of a hybrid vehicle, characterized in that: Applied to a hybrid electric vehicle with a P2 architecture, the hybrid electric vehicle torque control method includes: When the clutch between the engine and the motor is in the engaged state, check whether the required torque and speed of the drive axle wheel end are within the economic output band of the engine; If the required torque and speed of the drive axle wheel end fall outside the engine economic output band, the optimal engine torque corresponding to the required speed of the drive axle wheel end is found on the engine economic optimal curve; The motor required speed is set to be equal to the drive axle wheel end required speed, and the motor required torque is set to be equal to the difference between the drive axle wheel end required torque and the engine optimal torque, and the steps of the motor torque control method according to any one of claims 1 to 3 are performed; The engine output torque is controlled to be equal to the difference between the engine optimal torque or the required torque at the drive axle wheel end and the motor output torque.

8. The hybrid vehicle torque control method according to claim 7, wherein: After the step of checking whether the required torque and speed of the drive axle wheel end fall within the economic output band of the engine, the method further includes: If the drive axle wheel end required torque and the drive axle wheel end required speed fall within the engine economic output band, the engine output torque is controlled to be equal to the drive axle wheel end required torque, and the motor output torque is controlled to be equal to zero.

9. The hybrid vehicle torque control method according to claim 7, wherein: The hybrid vehicle torque control method further includes: When the clutch between the engine and the motor is in a disconnected state, the motor required speed is equal to the drive axle wheel end required speed, and the motor required torque is equal to the drive axle wheel end required torque, and the steps of the motor torque control method according to any one of claims 1 to 3 are executed.

10. A motor torque control device, characterized in that: The motor torque control device comprises: Rated search module, used to find the motor rated torque corresponding to the motor required speed on the motor external characteristic curve; A first output module, configured to control the motor output torque to be equal to the motor demand torque if the motor demand torque is less than or equal to the motor rated torque; A second output module is configured to control the motor output torque to be equal to the motor demand torque if the motor demand torque is greater than the motor rated torque and the motor real-time temperature is less than or equal to a reduction threshold, wherein the reduction threshold is less than a temperature protection threshold; The third output module is used to control the motor output torque between zero and the motor required torque if the motor required torque is greater than the motor rated torque, and the motor real-time temperature is less than the temperature protection threshold and greater than the reduction threshold, wherein the closer the motor real-time temperature is to the reduction threshold, the closer the motor output torque is to the motor required torque, and the closer the motor real-time temperature is to the temperature protection threshold, the closer the motor output torque is to zero.

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