Motor torque limiting method, device, controller and computer readable storage medium

Abstract

The present application discloses a motor torque limiting method, device, controller and computer-readable storage medium, the method comprising: obtaining the expected power and actual power of the power battery; if the actual power is greater than the expected power, determining the torque correction data according to the actual power and the expected power; determining the driving motor limiting torque according to the torque correction data; determining the requested motor torque according to the driving motor limiting torque and the motor demand torque. The technical solution disclosed in the present application determines the torque correction data according to the actual power and the expected power of the power battery when the actual power of the power battery is greater than the expected power, and determines the driving motor limiting torque according to the torque correction data, so as to reduce the boundary torque of the driving motor limiting torque through the torque correction data, so that the torque limit can control the actual power of the power battery to be within the capacity range of the peak power as much as possible, thereby ensuring the safety and life of the power battery.

Description

Technical Field

[0001] The present application relates to the field of power system control technology, and in particular to a motor torque limiting method, device, controller and computer-readable storage medium. Background Art

[0002] In a power system including a power battery and a motor, the motor torque needs to be limited in order to ensure the safety and life of the power battery.

[0003] Currently, when the motor torque is limited, the power of the power battery will exceed the peak power capacity due to the decrease in control accuracy, thereby reducing the safety and life of the power battery. Summary of the invention

[0004] In view of the above problems, the present application provides a motor torque limiting method, device, controller and computer-readable storage medium to ensure the safety and life of the power battery.

[0005] In a first aspect, the present application provides a motor torque limiting method, comprising:

[0006] Obtain the expected power and actual power of the power battery;

[0007] If the actual power is greater than the expected power, determining torque correction data according to the actual power and the expected power;

[0008] Determining the maximum torque of the motor allowed by the power battery according to the torque correction data;

[0009] Acquire the maximum torque allowed by the drive motor, and determine the limit torque of the drive motor according to the maximum torque allowed by the power battery and the maximum torque allowed by the drive motor;

[0010] The requested motor torque is determined according to the drive motor limit torque and the motor required torque.

[0011] In the technical solution of the embodiment of the present application, when the actual power of the power battery is greater than the expected power, torque correction data is determined according to the actual power and the expected power of the power battery, and the driving motor limiting torque is determined according to the torque correction data, so as to reduce the boundary torque of the driving motor limiting torque through the torque correction data, thereby improving the problem that the torque limitation cannot control the actual power of the power battery within the capacity range of the peak power due to the reduction in control accuracy, so that the torque limitation can control the actual power of the power battery within the capacity range of the peak power as much as possible, reduce overcharging and over-discharging of the power battery, and ensure the safety and life of the power battery.

[0012] In some embodiments, determining the limiting torque of the driving motor according to the torque correction data includes:

[0013] Determining the maximum torque of the motor allowed by the power battery according to the torque correction data;

[0014] The maximum torque allowed by the drive motor is obtained, and the limit torque of the drive motor is determined according to the maximum torque allowed by the power battery and the maximum torque allowed by the drive motor.

[0015] Through the above implementation, the maximum torque of the motor allowed by the power battery is determined by utilizing the torque correction data determined according to the actual power and expected power of the power battery, so as to reduce the maximum torque of the motor allowed by the power battery through the torque correction data, and the final drive motor limit torque, which is the boundary torque, is determined based on the two parameters of the maximum torque of the motor allowed by the power battery and the maximum torque of the motor allowed by the drive motor, so as to improve the rationality, reliability and accuracy of the determination of the drive motor limit torque, thereby better performing the motor torque limitation, so that the actual power of the power battery can be as far as possible within the capacity range of the peak power, thereby ensuring the safety and life of the power battery.

[0016] In some embodiments, determining torque correction data according to the actual power and the expected power includes:

[0017] determining a torque scaling factor according to a ratio of the actual power to the expected power;

[0018] Using the torque scaling factor as the torque correction data;

[0019] Determining the maximum torque of the motor allowed by the power battery according to the torque correction data includes:

[0020] Get the original value of the maximum torque allowed by the power battery for the motor;

[0021] The torque correction data is used to correct the original value of the maximum torque of the motor allowed by the power battery to obtain the maximum torque of the motor allowed by the power battery.

[0022] By determining the torque scaling factor according to the ratio of the actual power and the expected power of the power battery, and applying the torque scaling factor to the original value of the maximum torque of the motor allowed by the power battery, the maximum torque of the motor allowed by the power battery can be scaled, thereby achieving the scaling of the limiting torque of the drive motor, thereby improving the problem that the actual torque control cannot control the actual charging and discharging power of the power battery within the peak power capacity due to the decrease in control accuracy.

[0023] In some embodiments, determining a torque scaling factor according to a ratio of the actual power to the expected power includes:

[0024] Selecting a maximum ratio of the actual power to the expected power from a plurality of control cycles;

[0025] The torque scaling factor is determined based on the maximum ratio.

[0026] By selecting the maximum ratio of actual power to expected power, the maximum deviation state within the past multiple control cycles can be locked to include all deviations within the maximum deviation range, so that the drive motor limit torque determined based on the maximum ratio can be effective for a long time and the actual power of the power battery can be limited to the peak power capacity. In addition, the driving impact caused by the fluctuation of the maximum torque allowed by the power battery and the drive motor limit torque can be reduced to improve the driving experience.

[0027] In some embodiments, obtaining the original value of the maximum torque allowed by the power battery for the motor includes:

[0028] Obtaining the maximum power of the motor allowed by the power battery, the energy conversion efficiency of the drive motor, and the speed of the drive motor;

[0029] An original value of the maximum torque allowed by the power battery for the motor is determined according to the maximum power allowed by the power battery for the motor, the energy conversion efficiency of the drive motor and the rotation speed of the drive motor.

[0030] The above method can improve the accuracy of calculating the original value of the maximum torque allowed by the power battery for the motor, so as to improve the accuracy of determining the limit torque of the drive motor, and further improve the accuracy of the motor torque limit.

[0031] In some embodiments, it also includes:

[0032] Obtaining the energy conversion efficiency of the drive motor and the rotation speed of the drive motor;

[0033] Determining torque correction data according to the actual power and the expected power includes:

[0034] Determining correction data of the maximum torque allowed by the power battery according to the difference between the actual power and the expected power, the energy conversion efficiency of the drive motor and the speed of the drive motor;

[0035] Using the maximum torque correction data of the motor allowed by the power battery as the torque correction data;

[0036] Determining the maximum torque of the motor allowed by the power battery according to the torque correction data includes:

[0037] Get the original value of the maximum torque allowed by the power battery for the motor;

[0038] The torque correction data is used to correct the original value of the maximum torque of the motor allowed by the power battery to obtain the maximum torque of the motor allowed by the power battery.

[0039] Through the above implementation, the deviation between the actual power and the expected power of the power battery is converted into a torque deviation, and the torque deviation is subtracted from the original value of the maximum torque of the motor allowed by the power battery, so as to realize the correction of the original value of the maximum torque of the motor allowed by the power battery based on the deviation, thereby reducing the maximum torque of the motor allowed by the power battery, so as to reduce the boundary torque of the driving motor limiting torque, and then the actual power of the power battery can be as far as possible within the peak power capacity range, so as to ensure the safety and life of the power battery.

[0040] In some embodiments, determining torque correction data according to the actual power and the expected power includes:

[0041] Determining power battery power correction data according to the difference between the actual power and the expected power;

[0042] Using the power battery power correction data as the torque correction data;

[0043] Determining the maximum torque of the motor allowed by the power battery according to the torque correction data includes:

[0044] Obtaining the maximum power of the motor allowed by the power battery, the energy conversion efficiency of the drive motor, and the speed of the drive motor;

[0045] Correcting the maximum power of the motor allowed by the power battery according to the torque correction data to obtain the corrected maximum power of the motor allowed by the power battery;

[0046] The maximum torque allowed by the power battery for the motor is determined according to the corrected maximum power allowed by the power battery for the motor, the energy conversion efficiency of the drive motor and the rotation speed of the drive motor.

[0047] Through the above implementation, the maximum power allowed by the power battery for the motor is corrected according to the deviation between the actual power of the power battery and the expected power, and the corrected maximum power allowed by the power battery for the motor is involved in the determination of the maximum torque allowed by the power battery for the motor, so as to reduce the maximum torque allowed by the power battery for the motor, thereby facilitating the reduction of the boundary torque of the driving motor limiting torque, and further allowing the actual power of the power battery to be as far as possible within the capacity range of the peak power, so as to ensure the safety and life of the power battery.

[0048] In some embodiments, obtaining the expected power of the power battery includes:

[0049] Acquiring historical requested motor torque, energy conversion efficiency of the drive motor, speed of the drive motor and power consumption of high-voltage accessories;

[0050] The expected power of the power battery is determined according to the historical requested motor torque, the energy conversion efficiency of the drive motor, the rotation speed of the drive motor and the power consumption of the high-voltage accessories.

[0051] Through the above, the accuracy of determining the expected power of the power battery can be improved, so as to improve the accuracy of calculating the torque correction data, thereby improving the accuracy of determining the limiting torque of the drive motor.

[0052] In some embodiments, when the operating condition of the power battery is a driving condition, obtaining the expected power and the actual power of the power battery includes:

[0053] Obtain the expected discharge power and actual discharge power of the power battery;

[0054] Determining torque correction data according to the actual power and the expected power includes:

[0055] determining driving torque correction data according to the actual discharge power and the expected discharge power;

[0056] Determining the limiting torque of the driving motor according to the torque correction data includes:

[0057] The driving motor driving limit torque is determined based on the driving torque correction data.

[0058] Through the above, it is possible to limit the motor torque when the power battery is in a driving condition, so that the discharge power of the power battery can be as close as possible to the peak discharge power capacity range, thereby reducing over-discharge of the power battery and ensuring the safety and life of the power battery.

[0059] In some embodiments, when the operating condition of the power battery is an energy recovery condition, obtaining the expected power and the actual power of the power battery includes:

[0060] Obtain the expected recovery power and actual recovery power of the power battery;

[0061] Determining torque correction data according to the actual power and the expected power includes:

[0062] determining energy recovery torque correction data according to the actual recovery power and the expected recovery power;

[0063] Determining the limiting torque of the driving motor according to the torque correction data includes:

[0064] The driving motor recovery limit torque is determined according to the energy recovery torque correction data.

[0065] Through the above, it is possible to limit the motor torque when the power battery is in the energy recovery condition, so that the charging power of the power battery can be as close as possible to the peak charging power capacity range, so as to reduce overcharging of the power battery, thereby ensuring the safety and life of the power battery.

[0066] In a second aspect, the present application provides a motor torque limiting device, comprising:

[0067] A first acquisition module is used to acquire the expected power and actual power of the power battery;

[0068] a first determination module, configured to determine torque correction data according to the actual power and the expected power if the actual power is greater than the expected power;

[0069] A second determination module, configured to determine a limit torque of the drive motor according to the torque correction data;

[0070] The torque limiting module is used to determine the requested motor torque according to the driving motor limited torque and the motor required torque.

[0071] In a third aspect, the present application provides a controller, comprising:

[0072] Memory for storing computer programs;

[0073] A processor is used to implement the steps of any one of the motor torque limiting methods described above when executing the computer program.

[0074] In a fourth aspect, the present application provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the motor torque limiting method as described in any one of the above items are implemented.

[0075] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0076] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Moreover, the same reference numerals are used throughout the drawings to represent the same components. In the drawings:

[0077] Figure 1A flow chart of a motor torque limiting method according to some embodiments of the present application;

[0078] Figure 2 A flowchart for determining a torque scaling factor for some embodiments of the present application;

[0079] Figure 3 A flowchart for determining the limiting torque of a driving motor according to some embodiments of the present application;

[0080] Figure 4 A flowchart for determining a torque scaling factor for some embodiments of the present application;

[0081] Figure 5 A flowchart for determining the limiting torque of a driving motor according to some embodiments of the present application;

[0082] Figure 6 A flowchart for determining the limiting torque of a driving motor according to some embodiments of the present application;

[0083] Figure 7 A flowchart for determining the limiting torque of a driving motor according to some embodiments of the present application;

[0084] Figure 8 A flowchart for determining the limiting torque of a driving motor according to some embodiments of the present application;

[0085] Fig. 9 This is a motor torque limiting control framework diagram of some embodiments of the present application;

[0086] Fig.10 This is a schematic diagram of the structure of a motor torque limiting device in some embodiments of the present application;

[0087] Fig.11 This is a schematic diagram of the structure of the controller of some embodiments of the present application. DETAILED DESCRIPTION

[0088] The following embodiments of the technical solution of the present application are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application, and are therefore only used as examples, and cannot be used to limit the scope of protection of the present application.

[0089] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned figure descriptions and any variations thereof are intended to cover non-exclusive inclusions.

[0090] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.

[0091] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0092] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of the associated objects, indicating that there may be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0093] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0094] At present, when the motor torque is limited for a power system including a power battery and a motor, the control accuracy will be reduced due to factors such as deviation between the calculated efficiency MAP (a data curve that reflects the distribution of motor efficiency at different speeds and torques) and the actual efficiency, abnormal losses in the power system, etc., resulting in the actual torque limit being unable to control the actual power of the power battery within its peak power capacity, which in turn causes overcharging and over-discharging of the power battery, reducing the safety and life of the power battery.

[0095] To this end, the applicant proposed a motor torque limiting method, which monitors the actual power and expected power of the power battery in real time. When the actual power of the power battery is greater than the expected power, the torque correction data is determined according to the actual power and the expected power of the power battery, and the torque correction data is involved in the determination of the boundary torque of the driving motor limiting torque to reduce the boundary torque of the driving motor limiting torque, thereby improving the problem that the torque limitation cannot control the actual power of the power battery within the capacity range of the peak power of the power battery due to the decrease in control accuracy, so that the torque limitation can control the actual power of the power battery to be within the capacity range of the peak power as much as possible, so as to ensure the safety and life of the power battery.

[0096] It should be noted that the motor torque limit provided in the present application is applicable to a power system including a power battery and a motor, and the power system can be located in an electric vehicle (such as a pure electric vehicle), a spacecraft, etc.

[0097] See also Figure 1 , which is a flow chart of a motor torque limiting method in some embodiments of the present application, and may include the following steps:

[0098] S11: Obtaining expected power and actual power of the power battery.

[0099] It should be noted that the execution subject of the embodiment of the present application may be a controller. Taking the case where the power system is located in an electric vehicle as an example, the controller mentioned here may specifically be a vehicle computer, a vehicle controller, a domain controller, etc. The software contained in the controller may be periodically operated according to a certain control cycle (e.g., 10ms, etc.) to periodically limit the motor torque and realize other calculations and controls.

[0100] First, the controller can obtain the actual power and expected power of the power battery in the power system at the current moment. Among them, the expected power of the power battery is the power that the power battery is expected to consume. This power can be calculated based on the expected power consumption of the drive motor and the actual power consumption of the high-voltage accessories. The expected power consumption of the drive motor can be calculated based on the current speed of the drive motor and the current energy conversion efficiency of the drive motor. The energy conversion efficiency of the drive motor can be obtained by querying the drive motor efficiency table, and the drive motor efficiency table is obtained based on the drive motor bench test data. The actual power of the power battery is the power actually consumed by the power battery, which can be obtained by obtaining the bus voltage and current and multiplying the bus voltage and current.

[0101] S12: If the actual power is greater than the expected power, torque correction data is determined according to the actual power and the expected power.

[0102] Based on step S11 , it can be determined whether the actual power of the power battery is greater than the expected power of the power battery.

[0103] If the actual power of the power battery is not greater than the expected power of the power battery, it indicates that the actual power of the power battery is within the expected power range and does not exceed the expected power, which means that there is almost no deviation between the energy conversion efficiency of the drive motor and the actual conversion efficiency, and the actual power consumption of the power battery will not exceed the capacity range of its peak power. Therefore, the controller can determine the drive motor limit torque in an existing manner and request the motor torque based on the driver's required motor torque and the determined drive motor limit torque.

[0104] If the actual power of the power battery is greater than the expected power of the power battery, it indicates that the actual power of the power battery is outside the expected power range and has exceeded the expected power, which means that there is a deviation between the energy conversion efficiency of the drive motor and the actual conversion efficiency. In this case, the boundary torque of the drive motor limit torque can be corrected. Specifically, first, the torque correction data at the current moment can be determined based on the actual power and the expected power of the power battery. The torque correction data can characterize the degree of reduction in the control accuracy of the drive motor, such as the reduction in control accuracy caused by the deviation between the energy conversion efficiency of the drive motor and the actual conversion efficiency.

[0105] S13: Determine the limit torque of the drive motor according to the torque correction data.

[0106] On the basis of step S12, the driving motor limiting torque can be determined according to the determined torque correction data, that is, the degree of control accuracy reduction is involved in the determination of the driving motor limiting torque boundary torque, so as to reduce the driving motor limiting torque boundary torque according to the degree of control accuracy reduction, that is, the driving motor limiting torque determined when the actual power of the power battery is greater than the expected power is less than the driving motor limiting torque under normal circumstances (that is, the driving motor limiting torque when the actual power of the power battery is not greater than the expected power). The reduction of the driving motor limiting torque boundary torque can make up for the reduction in control accuracy, thereby greatly improving the problem that the actual torque limit cannot control the actual power of the power battery within the peak power capacity due to the reduction in control accuracy, so as to avoid overcharging and over-discharging of the power battery and ensure the safety and life of the power battery.

[0107] The limit torque of the driving motor is the boundary torque of the actual torque of the driving motor, and the actual torque of the driving motor does not exceed the limit torque of the driving motor.

[0108] S14: Determine the requested motor torque according to the driving motor limit torque and the motor required torque.

[0109] In addition, the controller can also obtain the motor demand torque, which is the demand torque for the drive motor. Among them, obtaining the motor demand torque and the above steps S11-S13 are not limited in the execution order. When the power system is located in an electric vehicle, the motor demand torque is the driving demand motor torque. In this case, the motor torque limit provided in the embodiment of the present application can be applicable to driver driving and unmanned driving. When the driver is driving, the accelerator pedal opening signal can be obtained, and the driving demand motor torque can be obtained according to the analysis of the accelerator pedal opening signal. When it is unmanned, the driving demand motor torque can be directly obtained.

[0110] After obtaining the motor demand torque and determining the drive motor limit torque, the controller can limit the motor demand torque according to the drive motor limit torque so that the motor demand torque does not exceed the drive motor limit torque. That is to say, when the motor demand torque exceeds the drive motor limit torque, the drive motor limit torque is used as the requested motor torque; when the motor demand torque does not exceed the drive motor limit torque, the motor demand torque is used as the requested motor torque, that is, the controller specifically uses the minimum of the drive motor limit torque and the motor demand torque as the requested motor torque, so that the requested motor torque is not greater than the maximum torque allowed by the drive motor and the power battery is kept as far as possible from exceeding its charge and discharge capacity.

[0111] After determining the requested motor torque, the controller can send the requested motor torque to the drive motor system so that the drive motor in the drive motor system can output torque according to the requested motor torque, thereby scaling the drive motor limit torque so that the drive motor can operate at a torque not greater than the drive motor limit torque, thereby making the subsequent actual power of the power battery as far as possible within the capacity of the power battery peak power, so as to reduce the probability of overcharging and over-discharging of the power battery, and then ensure the safety and life of the power battery.

[0112] It should be noted that the controller can continuously obtain the expected power and actual power of the power battery, and determine the torque correction data when the actual power of the power battery is greater than the expected power, and involve the torque correction data in the determination of the driving motor limiting torque, that is, the controller can continue to perform the above-mentioned motor torque limitation process, so as to ultimately limit the actual power of the power battery to within the capacity range of the peak power of the power battery, thereby reducing the probability of overcharging and over-discharging of the power battery, so as to ensure the safety and life of the power battery.

[0113] The above-mentioned technical scheme disclosed in the embodiment of the present application determines torque correction data according to the actual power and the expected power of the power battery when the actual power of the power battery is greater than the expected power, and determines the driving motor limiting torque according to the torque correction data to reduce the boundary torque of the driving motor limiting torque, thereby improving the problem that the torque limitation cannot control the actual power of the power battery within the capacity range of the peak power due to the reduction in control accuracy, so that the torque limitation can control the actual power of the power battery to be within the capacity range of the peak power as much as possible, reduce overcharging and over-discharging of the power battery, and ensure the safety and life of the power battery.

[0114] According to some embodiments of the present application, determining the limiting torque of the driving motor according to the torque correction data may include:

[0115] Determine the maximum torque of the motor allowed by the power battery according to the torque correction data;

[0116] The maximum torque allowed by the drive motor is obtained, and the limit torque of the drive motor is determined according to the maximum torque allowed by the power battery and the maximum torque allowed by the drive motor.

[0117] When determining the limit torque of the drive motor according to the torque correction data, the maximum torque of the motor allowed by the power battery at the current moment can be determined according to the torque correction data, so that the torque correction data is involved in the determination of the maximum torque of the motor allowed by the power battery, that is, the degree of control accuracy reduction is involved in the determination of the maximum torque of the motor allowed by the power battery, so as to reduce the maximum torque of the motor allowed by the power battery, thereby reducing the limit torque of the drive motor. Among them, the maximum torque of the motor allowed by the power battery is the maximum torque of the drive motor allowed by the power battery.

[0118] In addition, the controller can also obtain the maximum torque allowed by the drive motor at the corresponding moment, which is the maximum torque allowed by the drive motor. Specifically, the controller can obtain the maximum torque allowed by the drive motor through a bus signal of a bus connected to the drive motor system.

[0119] After determining the maximum torque allowed by the power battery based on the torque correction data and obtaining the maximum torque allowed by the drive motor, the controller can determine the minimum of the maximum torque allowed by the power battery and the maximum torque allowed by the drive motor, and determine the determined minimum value as the drive motor limiting torque.

[0120] Through the above implementation, the torque correction data is used to reduce the maximum drive of the motor allowed by the power battery, thereby reducing the final drive motor limit torque, and the final drive motor limit torque is determined by integrating the maximum torque allowed by the power battery and the maximum torque allowed by the drive motor, thereby improving the rationality, reliability and accuracy of the determination of the drive motor limit torque, so as to better limit the motor torque, so that the actual power of the power battery can be as far as possible within the peak power capacity range, so as to ensure the safety and life of the power battery.

[0121] It should be noted that when the actual power of the power battery is not greater than the expected power, the original value of the maximum torque of the motor allowed by the power battery at the corresponding moment can be directly obtained, that is, the maximum torque of the motor allowed by the power battery can be corrected without correction. In this case, the original value of the maximum torque of the motor allowed by the power battery can be obtained, and the maximum torque of the motor allowed by the drive motor can be obtained. The limit torque of the drive motor is determined according to the original value of the maximum torque of the motor allowed by the power battery and the maximum torque of the motor allowed by the drive motor, and the motor demand torque is limited according to the limit torque of the drive motor. Among them, the original value of the maximum torque of the motor allowed by the power battery is the maximum torque of the motor allowed by the power battery determined at the corresponding moment when there is no torque correction data involved, which can be specifically determined according to the peak power of the power battery, the speed of the drive motor and the current energy conversion efficiency of the drive motor. The maximum torque of the motor allowed by the power battery determined when the actual power of the power battery is greater than the expected power is less than the original value of the maximum torque of the motor allowed by the power battery determined when the actual power of the power battery is not greater than the expected power. The maximum torque of the motor allowed by the power battery can be specifically determined according to the torque correction data, the peak power of the power battery, the speed of the drive motor and the current energy conversion efficiency of the drive motor.

[0122] According to some embodiments of the present application, see Figure 2 and Figure 3 ,in, Figure 2 A flowchart for determining a torque scaling factor in some embodiments of the present application is provided. Figure 3 This is a flow chart for determining the limiting torque of a drive motor in some embodiments of the present application, wherein the “×” in the figure represents a multiplication operation, Figure 3 The "Min" in the formula represents the minimum value operation. The torque correction data is determined based on the actual power and the expected power, which may include:

[0123] Determine the torque scaling factor based on the ratio of actual power to expected power;

[0124] The torque scaling factor is used as torque correction data;

[0125] Determining the maximum torque allowed by the power battery for the motor based on the torque correction data may include:

[0126] Get the original value of the maximum torque allowed by the power battery for the motor;

[0127] The torque correction data is used to correct the original value of the maximum torque allowed by the power battery for the motor, so as to obtain the maximum torque allowed by the power battery for the motor.

[0128] In the embodiment of the present application, when the actual power of the power battery is greater than the expected power, the ratio of the actual power of the power battery to the expected power can be obtained. Specifically, б=P treal / P Expect, where P treal is the actual power of the power battery, P Expect is the expected power of the power battery. Then, the torque scaling factor θ can be determined according to the ratio б of the actual power of the power battery to the expected power, where the ratio б is a value greater than 1, and the torque scaling factor θ can be a value less than 1. For example, the inverse of the currently obtained ratio б can be used as the torque scaling factor θ, or the maximum ratio б in the past multiple control cycles can be used as the torque scaling factor θ. max The inverse of the torque scaling factor θ can be used as the torque scaling factor θ, or the average value of the ratio in the past multiple control cycles б avg The inverse of (the average value of the ratio when the actual power of the power battery is greater than the expected power) is used as the torque scaling coefficient θ, etc. After the torque scaling coefficient θ is determined, the maximum torque of the motor allowed by the power battery can be determined according to the torque scaling coefficient θ, that is, the torque scaling coefficient θ can be used as the torque correction data to determine the maximum torque of the motor allowed by the power battery according to the torque correction data.

[0129] In the above case, when determining the maximum torque of the motor allowed by the power battery based on the torque correction data, first, the original value of the maximum torque of the motor allowed by the power battery can be obtained, and then the torque scaling factor θ can be multiplied by the original value of the maximum torque of the motor allowed by the power battery to scale the original value of the maximum torque of the motor allowed by the power battery using the torque scaling factor θ, so that the final maximum torque of the motor allowed by the power battery is less than the original value of the maximum torque of the motor allowed by the power battery.

[0130] Through the above, it is possible to directly apply the determined torque scaling coefficient to the original value of the maximum torque allowed by the power battery for the motor, so as to achieve the scaling of the maximum torque allowed by the power battery for the motor, thereby achieving the scaling of the limiting torque of the drive motor, and improving the problem that the actual torque control cannot control the actual charging and discharging power of the power battery within the peak power capacity due to the decrease in control accuracy.

[0131] It should be noted that Figure 2 The example of the maximum torque allowed by the power battery is explained by setting the torque scaling factor θ=1 when the actual power of the power battery is not greater than the expected power, and multiplying the torque scaling factor θ by the original value of the maximum torque allowed by the power battery to obtain the maximum torque allowed by the power battery. Of course, when the actual power of the power battery is not greater than the expected power, the original value of the maximum torque allowed by the power battery can be directly used in the motor torque limitation, or the original value of the maximum torque allowed by the power battery can be used as the maximum torque allowed by the power battery to participate in the motor torque limitation.

[0132] According to some embodiments of the present application, see Figure 4, which is a flow chart of determining a torque scaling factor in some embodiments of the present application. Determining the torque scaling factor according to the ratio of actual power to expected power may include:

[0133] Selecting a maximum ratio of actual power to expected power from a plurality of control cycles;

[0134] The torque scaling factor is determined based on the maximum ratio.

[0135] In the embodiment of the present application, when determining the torque scaling factor according to the ratio of the actual power and the expected power of the power battery, the maximum ratio of the actual power and the expected power can be selected from multiple control cycles. max , then, the maximum ratio б max The inverse of is taken as the torque scaling factor θ.

[0136] The multiple control cycles may specifically be the past N control cycles, where N is an integer greater than 1, and the specific value of N may be set according to actual conditions. The control cycle mentioned here may be, for example, the control cycle provided by the software in the controller. max The maximum deviation state within the past N control cycles can be locked (the deviation here can be understood as the deviation between the expected power and the actual power of the power battery, or the efficiency deviation of the drive motor, etc.) to include all deviations within the maximum deviation range, so that the maximum ratio based on max The determined driving motor limiting torque can be effective for a long time and limit the actual power of the power battery within the peak power capacity. In addition, it can also reduce the driving impact caused by the fluctuation of the power battery's maximum motor torque and the driving motor limiting torque, so as to improve the driving experience.

[0137] According to some embodiments of the present application, see Figure 5 , which is a flow chart of determining the limit torque of the drive motor in some embodiments of the present application. Obtaining the original value of the maximum torque allowed by the power battery for the motor may include:

[0138] Obtain the maximum power of the motor allowed by the power battery, the energy conversion efficiency of the drive motor, and the speed of the drive motor;

[0139] The original value of the maximum torque allowed by the power battery for the motor is determined based on the maximum power allowed by the power battery, the energy conversion efficiency of the drive motor and the speed of the drive motor.

[0140] In the embodiment of the present application, the original value of the maximum torque allowed by the power battery for the motor can be obtained specifically through the following process:

[0141] 11) Obtain the maximum power of the motor allowed by the power battery. Specifically, the peak power of the power battery can be obtained from the power battery system, and the current high-voltage accessory power consumption can be obtained from the high-voltage accessory system, wherein the high-voltage accessory power consumption is equal to the sum of the power consumption of high-voltage accessories such as DCDC (direct current-to-direct current converter), PTC (direct current heater), and compressor. The maximum power of the motor allowed by the power battery is calculated based on the peak power of the power battery and the power consumption of the high-voltage accessories. Specifically, when the power battery is in a driving condition (at this time, the power battery is in a discharging state), obtaining the maximum power of the motor allowed by the power battery is to obtain the maximum driving power P of the motor allowed by the power battery. vehdchgAllow , P vehdchgAllow Specifically, it is equal to the peak discharge power of the power battery minus the power consumption of the high-voltage accessories. When the drive battery is in the energy recovery state (at this time, the power battery is in the charging state), obtaining the maximum power allowed by the power battery is to obtain the maximum energy recovery power allowed by the power battery. vehchgAllow , P vehchgAllow It is equal to the peak charging power of the power battery plus the power consumed by the high-voltage accessories.

[0142] 12) Obtain the energy conversion efficiency η of the drive motor at the current moment and the speed n of the drive motor. Among them, the speed n of the drive motor (that is, the actual speed of the drive motor) can be obtained from the drive motor system. In addition, the torque of the drive motor (that is, the actual torque of the drive motor) can also be obtained from the drive motor system at the same time. Then, according to the obtained speed n and torque of the drive motor, the drive motor efficiency table (MAP) can be queried to obtain the energy conversion efficiency of the drive motor corresponding to the speed n and torque of the drive motor, that is, to obtain the energy conversion efficiency η of the drive motor at the current moment. Among them, the drive motor efficiency table is obtained based on the drive motor bench test data.

[0143] 13) According to the maximum power allowed by the power battery, the energy conversion efficiency η of the drive motor and the speed n of the drive motor, the conversion relationship between power, speed, efficiency and torque is used to calculate the original value of the maximum torque allowed by the power battery. Specifically, when the power battery is in the driving condition, the above process is based on the maximum drive power P allowed by the power battery. vehdchgAllow , driving efficiency η of the driving motor drv and the speed n of the drive motor, using T batdrvlmt =P vehdchgAllow *η drv *9550 / n calculates the original value T of the maximum driving torque allowed by the power battery batdrvlmt , where the driving efficiency η drv Specifically, the drive motor efficiency table (MAP) can be queried based on the drive motor speed n and current torque. drv) is obtained. When the driving battery is in the energy recovery state, the above process is based on the maximum energy recovery power P allowed by the power battery for the motor. vehchgAllow , Energy recovery efficiency of the drive motor η reg and the speed n of the drive motor, using T batreglmt =P vehchgAllow *9550 / (n*η reg ) Calculate the original value of the maximum energy recovery torque T allowed by the power battery batreglmt , where the energy recovery efficiency η reg Specifically, the drive motor energy recovery efficiency table (MAP) can be queried according to the drive motor speed n and current torque. reg )get.

[0144] The above method can improve the accuracy of calculating the original value of the maximum torque allowed by the power battery for the motor, so as to improve the accuracy of determining the limit torque of the drive motor, and further improve the accuracy of the motor torque limit.

[0145] According to some embodiments of the present application, see Figure 6 , which is a flow chart of determining the limiting torque of the driving motor in some embodiments of the present application. The motor torque limiting method may also include:

[0146] Obtaining the energy conversion efficiency and the rotation speed of the drive motor;

[0147] Determine torque correction data based on actual power and expected power, which may include:

[0148] Determine the correction data of the maximum torque allowed by the power battery according to the difference between the actual power and the expected power, the energy conversion efficiency of the drive motor and the speed of the drive motor;

[0149] The maximum torque correction data of the motor allowed by the power battery is used as the torque correction data;

[0150] Determining the maximum torque allowed by the power battery for the motor based on the torque correction data may include:

[0151] Get the original value of the maximum torque allowed by the power battery for the motor;

[0152] The torque correction data is used to correct the original value of the maximum torque allowed by the power battery for the motor, so as to obtain the maximum torque allowed by the power battery for the motor.

[0153] In the embodiment of the present application, before determining the torque correction data according to the actual power and the expected power, the speed n of the drive motor at the current moment (i.e., the actual speed of the drive motor) and the torque of the drive motor (i.e., the actual torque of the drive motor) can also be obtained from the drive motor system. Then, according to the obtained speed n and torque of the drive motor, the drive motor efficiency table (MAP) can be queried to obtain the energy conversion efficiency η of the drive motor corresponding to the speed n and torque of the drive motor.

[0154] Based on the above, the difference between the actual power and the expected power of the power battery (specifically P treal -P Expect ), the energy conversion efficiency η of the drive motor and the speed n of the drive motor, the conversion relationship between power, speed, efficiency and torque is used to calculate the maximum torque correction data of the power battery allowed by the motor (its unit is the same as the unit of torque), and the obtained maximum torque correction data of the power battery allowed by the motor can be used as the torque correction data. Among them, in the above process, the maximum difference between the actual power and the expected power of the power battery in the past N control cycles can be obtained, and the maximum torque correction data of the power battery allowed by the motor can be calculated according to the maximum difference. Of course, the difference between the actual power and the expected power of the power battery in the current control cycle can also be obtained, and the maximum torque correction data of the power battery allowed by the motor can be calculated according to the difference, or the average value of the difference between the actual power and the expected power of the power battery in the past N control cycles (all of which are the average values ​​of the difference when the actual power of the power battery is greater than the expected power) can be obtained, and the maximum torque correction data of the power battery allowed by the motor can be calculated according to the difference. Taking the difference between the actual power and the expected power of the power battery in the current control cycle as the maximum torque correction data of the power battery allowed by the motor as an example, when the power battery is in the driving condition, it can be specifically used T1=(P treal -P Expect )*η drv *9550 / n to calculate the maximum driving torque correction data T1 allowed by the power battery. When the driving battery is in the energy recovery condition, it can be specifically used T2 = (P treal -P Expec )*9550 / (n*η reg ) is calculated to obtain the correction data T2 of the maximum energy recovery torque allowed by the power battery. The correction data of the maximum torque allowed by the power battery is calculated based on the maximum difference or the average value of the difference between the actual power and the expected power of the power battery in the past N control cycles. Specifically, (P treal -P Expect ) is replaced by (P treal -P Expect ) NMAX or (P treal -PExpect ) NAVG That is, among which, (P treal -P Expect ) NMAX is the maximum difference between the actual power and the expected power of the power battery in the past N control cycles, (P treal -P Expect ) NAVG It is the average value of the difference between the actual power and the expected power of the power battery in the past N control cycles.

[0155] Accordingly, when determining the maximum torque allowed by the power battery for the motor according to the torque correction data, the original value of the maximum torque allowed by the power battery for the motor can be obtained first, wherein the method of obtaining the original value of the maximum torque allowed by the power battery for the motor is the same as in the above embodiment and will not be repeated here. Then, the original value of the maximum torque allowed by the power battery for the motor can be corrected using the correction data of the maximum torque allowed by the power battery for the motor. Specifically, the original value of the maximum torque allowed by the power battery for the motor can be subtracted from the correction data of the maximum torque allowed by the power battery for the motor to obtain the maximum torque allowed by the power battery for the motor.

[0156] Through the above, it is possible to convert the deviation between the actual power and the expected power of the power battery into a torque deviation, and subtract the torque deviation from the original value of the maximum torque allowed by the power battery for the motor, so as to correct the original value of the maximum torque allowed by the power battery for the motor based on the deviation. This can greatly improve the problem that the actual torque limit cannot control the actual power of the power battery within the peak power capacity due to the decrease in control accuracy, thereby improving the safety and life of the power battery.

[0157] According to some embodiments of the present application, see Figure 7 , which is a flow chart for determining the limiting torque of the drive motor in some embodiments of the present application. Determining torque correction data according to actual power and expected power may include:

[0158] Determine the power correction data of the power battery according to the difference between the actual power and the expected power;

[0159] Using the power battery power correction data as torque correction data;

[0160] Determining the maximum torque allowed by the power battery for the motor based on the torque correction data may include:

[0161] Obtain the maximum power of the motor allowed by the power battery, the energy conversion efficiency of the drive motor, and the speed of the drive motor;

[0162] The maximum power of the motor allowed by the power battery is corrected according to the torque correction data to obtain the maximum power of the motor allowed by the power battery after correction;

[0163] The maximum torque allowed by the power battery for the motor is determined based on the corrected maximum power allowed by the power battery for the motor, the energy conversion efficiency of the drive motor and the speed of the drive motor.

[0164] In the embodiment of the present application, in addition to the above two methods for determining the torque correction data, the torque correction data can also be determined directly based on the difference between the actual power and the expected power. Specifically, the difference between the actual power and the expected power of the power battery (specifically P treal -P Expect ), then, the difference between the actual power and the expected power of the power battery (specifically P treal -P Expect ) determines the power battery power correction data (whose unit is the same as the power unit), and the determined power battery power correction data can be used as torque correction data. In the above process, the maximum difference between the actual power and the expected power of the power battery in the past N control cycles can be obtained, and the maximum difference can be determined as the power battery power correction data. Of course, the difference between the actual power and the expected power of the power battery in the current control cycle can also be obtained, and the difference can be determined as the power battery power correction data, or the average value of the difference between the actual power and the expected power of the power battery in the past N control cycles can be obtained (both are the average value of the difference between the actual power and the expected power when the actual power is greater than the expected power).

[0165] On the basis of the above, when the maximum torque allowed by the power battery for the motor is determined according to the torque correction data, the maximum power allowed by the power battery for the motor, the energy conversion efficiency η of the drive motor and the speed n of the drive motor can be obtained. Among them, for the energy conversion efficiency η of the drive motor, the speed n of the drive motor and the torque of the drive motor can be obtained, and the corresponding energy conversion efficiency η can be obtained by querying the drive motor efficiency table (MAP) according to the speed n and torque of the drive motor. For the maximum power allowed by the power battery for the motor, the peak power of the power battery can be obtained from the power battery system, and the corresponding high-voltage accessory power consumption can be obtained from the high-voltage accessory system, and then the maximum power allowed by the power battery for the motor can be calculated according to the peak power of the power battery and the high-voltage accessory power consumption.

[0166] After determining the power battery power correction data and obtaining the maximum power of the motor allowed by the power battery, the power battery power correction data can be used to correct the maximum power of the motor allowed by the power battery. Specifically, the power battery power correction data can be subtracted from the maximum power of the motor allowed by the power battery to obtain the corrected maximum power of the motor allowed by the power battery. Then, the maximum torque of the motor allowed by the power battery can be calculated based on the corrected maximum power of the motor allowed by the power battery, the energy conversion efficiency η of the drive motor, and the speed n of the drive motor, using the conversion relationship between power, speed, efficiency and torque. Taking the difference between the actual power and the expected power of the power battery in the current control cycle as the power battery power correction data as an example, when the power battery is in a driving condition, obtaining the maximum power of the motor allowed by the power battery is to obtain the maximum driving power P of the motor allowed by the power battery. vehdchgAllow , using P' vehdchgAllow =P vehdchgAllow -(P treal -P Expect ) Calculate the maximum driving power P' of the motor allowed by the corrected power battery vehdchgAllow , and use T' batdrvlmt =P' vehdchgAllow *η drv *9550 / n Calculate the maximum torque T' allowed by the power battery batdrvlmt When the power battery is in the energy recovery state, obtaining the maximum power of the motor allowed by the power battery is to obtain the maximum energy recovery power P allowed by the power battery. vehchgAllow , using P' vehchgAllow =P vehchgAllow -(P treal -P Expect ) Calculate the corrected maximum energy recovery power P' allowed by the power battery vehchgAllow , and use T' batreglmt =P' vehchgAllow *9550 / (n*η reg ) Calculate the maximum energy recovery torque T' allowed by the power battery batreglmt It should be noted that, when determining the power battery power correction data based on the maximum difference or the average difference between the actual power and the expected power of the power battery in the past N control cycles, P' vehdchgAllow =P vehdchgAllow -(P treal -P Expect ) and P' vehchgAllow =P vehchgAllow -(P treal -P Expect ) in (P treal -P Expect ) is replaced by (P treal -PExpect ) NMAX or (P treal -P Expect ) NAVG That is, among which, (P treal -P Expect ) NMAX is the maximum difference between the actual power and the expected power of the power battery in the past N control cycles, (P treal -P Expect ) NAVG It is the average value of the difference between the actual power and the expected power of the power battery in the past N control cycles.

[0167] Through the above implementation, the maximum power allowed by the power battery for the motor is corrected according to the deviation between the actual power and the expected power of the power battery, and the corrected maximum power allowed by the power battery for the motor is included in the determination of the maximum torque allowed by the power battery for the motor, so as to reduce the maximum torque allowed by the power battery for the motor, thereby greatly improving the problem that the actual torque limitation cannot control the actual power of the power battery within the peak power capacity due to the decrease in control accuracy, so as to ensure the safety and life of the power battery.

[0168] According to some embodiments of the present application, obtaining the expected power of the power battery may include:

[0169] Obtain historical requested motor torque, drive motor energy conversion efficiency, drive motor speed and high-voltage accessory power consumption;

[0170] The expected power of the power battery is determined based on the historical requested motor torque, the energy conversion efficiency of the drive motor, the speed of the drive motor and the power consumption of the high-voltage accessories.

[0171] In the embodiment of the present application, the expected power of the power battery can be obtained specifically in the following manner:

[0172] 21) Get the historical requested motor torque T req ; Among them, the historical requested motor torque can specifically be the torque that the controller actually requested to drive the motor in the previous control cycle.

[0173] 22) Obtain the rotational speed n of the drive motor and the energy conversion efficiency η of the drive motor; wherein, the energy conversion efficiency η of the drive motor can be obtained by obtaining the rotational speed n of the drive motor and the torque of the drive motor, and querying the drive motor efficiency table according to the rotational speed n and torque of the drive motor.

[0174] 23) Obtaining the power consumption of the high-voltage accessories from the high-voltage accessory system; wherein, the embodiment of the present application does not limit the execution order of step 21)-step 23).

[0175] 24) According to the historical requested motor torque, the energy conversion efficiency of the drive motor and the speed of the drive motor, the expected power consumption of the drive motor is calculated by using the conversion relationship between torque, efficiency, speed and power. Specifically, when the power battery is in the driving condition, the historical requested motor torque T is obtained. req That is to obtain the requested driving motor driving torque T drvreq The expected power consumption of the driving motor obtained by the above calculation is the driving torque T of the driving motor according to the request drvreq , driving efficiency η of the driving motor drv and the speed n of the drive motor, using T drvreq *n / (9550*η drv ) is used to calculate the expected power consumption of the drive motor. When the power battery is in the energy recovery state, obtaining the historical requested motor torque is to obtain the requested drive motor recovery torque T regreq The expected power consumption of the driving motor obtained by the above calculation is the required driving motor recovery torque T regreq , Energy recovery efficiency of the drive motor η reg and the speed n of the drive motor, using T regreq *n*η reg / 9550 Calculate the expected power consumption of the drive motor.

[0176] 25) According to the expected power consumption of the driving motor and the power consumption of the high-voltage accessories (specifically, the actual power consumed by the high-voltage accessories), the expected power of the power battery is calculated. Specifically, when the power battery is in the driving condition, the above process is to use P dchgExpect =T drvreq *n / (9550*η drv )+P hvacc Calculate the expected discharge power P of the power battery dchgExpect , where P hvacc When the power battery is in the energy recovery state, the above process is to use P chgExpect =T regreq *n*η reg / 9550-P hvacc Calculate the expected recovery power P of the power battery chgExpect , where P hvacc Dissipates power for high voltage accessories.

[0177] The above can improve the accuracy of determining the expected power of the power battery, so as to accurately calculate the torque correction data based on the expected power of the power battery, thereby improving the accuracy of determining the maximum torque allowed by the power battery for the motor and the limiting torque of the drive motor, so that the actual power of the power battery can be as far as possible within the capacity range of the peak power.

[0178] According to some embodiments of the present application, when the operating condition of the power battery is a driving condition, obtaining the expected power and the actual power of the power battery may include:

[0179] Obtain the expected discharge power and actual discharge power of the power battery;

[0180] Determine torque correction data based on actual power and expected power, which may include:

[0181] Determine driving torque correction data according to actual discharge power and expected discharge power;

[0182] Determining the limit torque of the drive motor according to the torque correction data may include:

[0183] The driving motor driving limit torque is determined based on the driving torque correction data.

[0184] In the power system, the working conditions of the power battery can be divided into driving conditions (at this time, the power battery is in a discharging state) and energy recovery conditions (at this time, the power battery is in a charging state), and the motor torque can be limited for the power battery in driving conditions and energy recovery conditions respectively, so that the actual charge and discharge power of the power battery can be as far as possible within the peak power capacity range, reducing overcharge and overdischarge of the power battery to ensure the safety and life of the power battery. For details, please refer to Figure 8 , which is a flow chart for determining the limiting torque of the drive motor in some embodiments of the present application, wherein: Figure 8 It is a specific process for determining the limiting torque of the drive motor when the actual power of the power battery is greater than the expected power.

[0185] When the power battery is in driving condition, the motor torque limiting process is: Get the expected discharge power P of the power battery dchgExpect And the actual discharge power P dchgtreal ; If the actual discharge power P dchgtreal Greater than the expected discharge power P dchgExpect , then according to the actual discharge power P dchgtreal and expected discharge power P dchgExpect Determine the driving torque correction data (the driving torque correction data is the torque correction data under the driving condition, which can be specifically the driving torque scaling coefficient θ drv , power battery allowed motor maximum driving torque correction data, power battery discharge power correction data); determine the driving motor driving limit torque according to the driving torque correction data; determine the requested motor torque according to the driving motor driving limit torque and the motor required torque.

[0186] On the basis of the above, determining the maximum torque of the motor allowed by the power battery according to the torque correction data in some of the above embodiments is to determine the maximum driving torque allowed by the power battery according to the driving torque correction data, wherein the maximum driving torque allowed by the power battery is the maximum driving torque of the driving motor allowed by the power battery. Obtaining the maximum torque allowed by the driving motor is to obtain the maximum driving torque allowed by the driving motor, wherein the maximum driving torque allowed by the driving motor is the maximum driving torque allowed by the driving motor. Determining the limiting torque of the driving motor according to the maximum torque allowed by the power battery and the maximum torque allowed by the driving motor is to determine the driving limiting torque of the driving motor according to the maximum driving torque allowed by the power battery and the maximum driving torque allowed by the driving motor, and the driving limiting torque of the driving motor is the boundary torque of the actual torque of the driving motor when the power battery is in the driving condition (at this time, the power battery is in the discharging state). Obtaining the original value of the maximum torque allowed by the power battery is to obtain the original value T of the maximum driving torque allowed by the power battery. batdrvlmt Obtaining the maximum power of the motor allowed by the power battery is to obtain the maximum driving power P allowed by the power battery. vehdchgAllow , P vehdchgAllow Specifically, it is equal to the peak discharge power of the power battery minus the power consumption of the high-voltage accessories. Obtaining the energy conversion efficiency of the drive motor is to obtain the drive efficiency η of the drive motor. drv , the driving efficiency η drv Specifically, you can query the drive motor efficiency table (MAP) according to the speed n and torque of the drive motor. drv )get.

[0187] For detailed description of the above parts, please refer to the description of the relevant parts in the above corresponding embodiments, which will not be repeated here.

[0188] Through the above, it is possible to limit the motor torque when the power battery is in a driving condition, so that the discharge power of the power battery can be as close as possible to the peak discharge power capacity range, thereby reducing over-discharge of the power battery and improving the safety and life of the power battery.

[0189] According to some embodiments of the present application, when the operating condition of the power battery is an energy recovery condition, obtaining the expected power and the actual power of the power battery may include:

[0190] Obtain the expected recovery power and actual recovery power of the power battery;

[0191] Determine torque correction data based on actual power and expected power, which may include:

[0192] Determine energy recovery torque correction data according to actual recovery power and expected recovery power;

[0193] Determining the limit torque of the drive motor according to the torque correction data may include:

[0194] The drive motor regeneration limit torque is determined according to the energy regeneration torque correction data.

[0195] In addition, when the power battery is in the energy recovery state, the motor torque limiting process is: obtain the expected recovery power P of the power battery chgExpect and the actual recovery power P chgtreal ; If the actual recovery power P chgtreal Greater than expected recovery power P chgExpect , then according to the actual recovery power P chgtreal and expected recovery power P chgExpect Determine the energy recovery torque correction data (the energy recovery torque correction data is the torque correction data under the energy recovery condition, which can be specifically the energy recovery torque scaling factor θ reg , power battery allowed motor maximum energy recovery torque correction data, power battery recovery power correction data); determine the drive motor recovery limit torque according to the energy recovery torque correction data; determine the requested motor torque according to the drive motor recovery limit torque and the motor demand torque.

[0196] On the basis of the above, determining the maximum torque of the motor allowed by the power battery according to the torque correction data in some of the above embodiments is to determine the maximum energy recovery torque allowed by the power battery according to the energy recovery torque correction data, wherein the maximum energy recovery torque allowed by the power battery is the maximum recovery torque of the drive motor allowed by the power battery. Obtaining the maximum torque allowed by the drive motor is to obtain the maximum recovery torque allowed by the drive motor, wherein the maximum recovery torque allowed by the drive motor is the maximum recovery torque allowed by the drive motor. Determining the limit torque of the drive motor according to the maximum torque allowed by the power battery and the maximum torque allowed by the drive motor is to determine the recovery limit torque of the drive motor according to the maximum energy recovery torque allowed by the power battery and the maximum recovery torque allowed by the drive motor, and the recovery limit torque of the drive motor is the boundary torque of the actual torque of the drive motor when the power battery is in the energy recovery condition. Obtaining the original value of the maximum torque allowed by the power battery is to obtain the original value T of the maximum energy recovery torque allowed by the power battery. batreglmt Obtaining the maximum power of the motor allowed by the power battery is to obtain the maximum energy recovery power P allowed by the power battery for the motor. vehchgAllow , P vehchgAllow It is equal to the peak charging power of the power battery plus the power consumption of the high-voltage accessories. The energy conversion efficiency of the drive motor is the energy recovery efficiency η of the drive motor. reg , the energy recovery efficiency η reg Specifically, you can query the drive motor energy recovery efficiency table (MAP) according to the speed n and torque of the drive motor.reg )get.

[0197] For detailed description of the above parts, please refer to the description of the relevant parts in the above corresponding embodiments, which will not be repeated here.

[0198] Through the above, it is possible to limit the motor torque when the power battery is in the energy recovery condition, so that the charging power of the power battery can be as close as possible to the peak charging power capacity range, so as to reduce overcharging of the power battery, thereby improving the safety and life of the power battery.

[0199] In addition, see Fig. 9 , which is a motor torque limit control framework diagram of some embodiments of the present application, wherein, Fig. 9 An example is given for explaining that an electric vehicle is used, and the motor demand torque is the driver demand torque, and the driving demand torque is obtained by obtaining the accelerator pedal opening signal and analyzing the accelerator pedal opening signal. Fig. 9 Take the controller as a domain controller as an example. Specifically, after the domain controller analyzes the driver's required torque according to the accelerator pedal opening signal, it limits the driver's required torque according to the peak power of the power battery, the actual power consumption of the high-voltage accessories, and the maximum torque allowed by the drive motor, ensuring that the motor torque requested by the domain controller is not greater than the maximum torque allowed by the drive motor system and does not cause the power battery to exceed its charge and discharge capacity, thereby improving the safety and life of the power battery.

[0200] The present application also provides a motor torque limiting device, which can be found in Fig.10 , which is a schematic diagram of the structure of the motor torque limiting device of some embodiments of the present application, the motor torque limiting device 100 may include: a first acquisition module 101, a first determination module 102, a second determination module 103 and a torque limiting module 104. Among them, the first acquisition module 101 is used to obtain the expected power and actual power of the power battery; the first determination module 102 is used to determine the torque correction data according to the actual power and the expected power if the actual power is greater than the expected power; the second determination module 103 is used to determine the limit torque of the drive motor according to the torque correction data; the torque limiting module 104 is used to determine the request motor torque according to the limit torque of the drive motor and the motor demand torque.

[0201] According to some embodiments of the present application, the second determination module 103 determines the limiting torque of the drive motor based on the torque correction data, and is specifically used to determine the maximum torque of the motor allowed by the power battery based on the torque correction data; obtains the maximum torque of the drive motor allowed by the drive motor, and determines the limiting torque of the drive motor by the smaller of the maximum torque of the motor allowed by the power battery and the maximum torque of the motor allowed by the drive motor.

[0202] According to some embodiments of the present application, the first determination module 102 determines the torque scaling factor according to the ratio of actual power to expected power, specifically for determining the torque scaling factor according to the ratio of actual power to expected power; and uses the torque scaling factor as torque correction data.

[0203] Furthermore, the second determination module 103 determines the maximum torque of the motor allowed by the power battery according to the torque correction data, which is specifically used to obtain the original value of the maximum torque of the motor allowed by the power battery; the original value of the maximum torque of the motor allowed by the power battery is corrected using the torque correction data to obtain the maximum torque of the motor allowed by the power battery.

[0204] According to some embodiments of the present application, the first determination module 102 determines the torque scaling factor based on the ratio of actual power to expected power, specifically for selecting the maximum ratio of actual power to expected power from multiple control cycles; and determining the torque scaling factor based on the maximum ratio.

[0205] According to some embodiments of the present application, the second determination module 103 obtains the original value of the maximum torque of the motor allowed by the power battery, which is specifically used to obtain the maximum power of the motor allowed by the power battery, the energy conversion efficiency of the drive motor and the speed of the drive motor; based on the maximum power of the motor allowed by the power battery, the energy conversion efficiency of the drive motor and the speed of the drive motor, the original value of the maximum torque of the motor allowed by the power battery is determined.

[0206] According to some embodiments of the present application, the motor torque limiting device 100 may further include a second acquisition module, the second acquisition module being used to acquire the energy conversion efficiency of the drive motor and the rotation speed of the drive motor;

[0207] The first determination module 102 determines torque correction data according to the actual power and the expected power, and is specifically used to determine the maximum torque correction data of the motor allowed by the power battery according to the difference between the actual power and the expected power, the energy conversion efficiency of the drive motor and the speed of the drive motor; and uses the maximum torque correction data of the motor allowed by the power battery as the torque correction data;

[0208] The second determination module 103 determines the maximum torque allowed by the power battery for the motor according to the torque correction data, and is specifically used to obtain the original value of the maximum torque allowed by the power battery for the motor; and is used to correct the original value of the maximum torque allowed by the power battery for the motor using the torque correction data to obtain the maximum torque allowed by the power battery for the motor.

[0209] According to some embodiments of the present application, the first determination module 102 determines the torque correction data according to the actual power and the expected power, and is specifically used to determine the power battery power correction data according to the difference between the actual power and the expected power; and uses the power battery power correction data as the torque correction data;

[0210] The second determination module 103 determines the maximum torque of the motor allowed by the power battery according to the torque correction data, which is specifically used to obtain the maximum power of the motor allowed by the power battery, the energy conversion efficiency of the drive motor and the speed of the drive motor; corrects the maximum power of the motor allowed by the power battery according to the torque correction data to obtain the corrected maximum power of the motor allowed by the power battery; determines the maximum torque of the motor allowed by the power battery according to the corrected maximum power of the motor allowed by the power battery, the energy conversion efficiency of the drive motor and the speed of the drive motor.

[0211] According to some embodiments of the present application, the first acquisition module 101 acquires the expected power and actual power of the power battery, and is specifically used to obtain the historical requested motor torque, the energy conversion efficiency of the drive motor, the speed of the drive motor and the power consumption of the high-voltage accessories; based on the historical requested motor torque, the energy conversion efficiency of the drive motor, the speed of the drive motor and the power consumption of the high-voltage accessories, the expected power of the power battery is determined.

[0212] According to some embodiments of the present application, when the operating condition of the power battery is a driving condition, the first acquisition module 101 acquires the expected power and the actual power of the power battery, and is specifically used to acquire the expected discharge power and the actual discharge power of the power battery; the first determination module 102 determines the torque correction data according to the actual power and the expected power, and is specifically used to determine the driving torque correction data according to the actual discharge power and the expected discharge power; the second determination module 103 determines the driving motor limiting torque according to the torque correction data, and is specifically used to determine the driving limiting torque of the driving motor according to the driving torque correction data.

[0213] According to some embodiments of the present application, when the operating condition of the power battery is an energy recovery condition, the first acquisition module 101 acquires the expected power and the actual power of the power battery, and is specifically used to acquire the expected recovery power and the actual recovery power of the power battery; the first determination module 102 determines the torque correction data based on the actual power and the expected power, and is specifically used to determine the energy recovery torque correction data based on the actual recovery power and the expected recovery power; the second determination module 103 determines the driving motor limiting torque based on the torque correction data, and is specifically used to determine the driving motor recovery limiting torque based on the energy recovery torque correction data.

[0214] This application also provides a controller, which can be found in Fig.11 , which is a schematic diagram of the structure of the controller of some embodiments of the present application, the controller 110 may include:

[0215] A memory 111, used for storing computer programs;

[0216] The processor 112 can implement the following steps when executing the computer program stored in the memory 111:

[0217] Obtain the expected power and actual power of the power battery; if the actual power is greater than the expected power, determine the torque correction data according to the actual power and the expected power; determine the limit torque of the drive motor according to the torque correction data; determine the requested motor torque according to the limit torque of the drive motor and the motor demand torque.

[0218] The present application also provides a computer-readable storage medium, in which a computer program is stored. When the computer program is executed by a processor, the following steps can be implemented:

[0219] Obtain the expected power and actual power of the power battery; if the actual power is greater than the expected power, determine the torque correction data according to the actual power and the expected power; determine the limit torque of the drive motor according to the torque correction data; determine the requested motor torque according to the limit torque of the drive motor and the motor demand torque.

[0220] The description of the relevant parts of a motor torque limiting device, a controller and a computer-readable storage medium provided in the present application can be found in the detailed description of the corresponding parts of a motor torque limiting method provided in the present application, and will not be repeated here.

[0221] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should all be included in the scope of the claims and specification of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A motor torque limiting method, characterized in that: include: Obtain the expected power and actual power of the power battery; If the actual power is greater than the expected power, determining torque correction data according to the actual power and the expected power; Determine the limit torque of the drive motor according to the torque correction data; Determine the requested motor torque according to the drive motor limit torque and the motor required torque; Determining the limiting torque of the driving motor according to the torque correction data includes: Determining the maximum torque of the motor allowed by the power battery according to the torque correction data; Acquire the maximum torque allowed by the drive motor, and determine the limit torque of the drive motor according to the maximum torque allowed by the power battery and the maximum torque allowed by the drive motor; If the actual power is not greater than the expected power, obtaining the original value of the maximum torque of the motor allowed by the power battery and the maximum torque of the motor allowed by the drive motor, and determining the limit torque of the drive motor according to the original value of the maximum torque of the motor allowed by the power battery and the maximum torque of the motor allowed by the drive motor; Obtaining the energy conversion efficiency of the drive motor and the rotation speed of the drive motor; Determining torque correction data according to the actual power and the expected power includes: Determining correction data of the maximum torque allowed by the power battery according to the difference between the actual power and the expected power, the energy conversion efficiency of the drive motor and the speed of the drive motor; Using the maximum torque correction data of the motor allowed by the power battery as the torque correction data; Determining the maximum torque of the motor allowed by the power battery according to the torque correction data includes: Get the original value of the maximum torque allowed by the power battery for the motor; Using the torque correction data, the original value of the maximum torque allowed by the power battery for the motor is corrected to obtain the maximum torque allowed by the power battery for the motor; Or, determining torque correction data according to the actual power and the expected power, comprising: Determining power battery power correction data according to the difference between the actual power and the expected power; Using the power battery power correction data as the torque correction data; Determining the maximum torque of the motor allowed by the power battery according to the torque correction data includes: Obtaining the maximum power of the motor allowed by the power battery, the energy conversion efficiency of the drive motor, and the speed of the drive motor; Correcting the maximum power of the motor allowed by the power battery according to the torque correction data to obtain the corrected maximum power of the motor allowed by the power battery; The maximum torque allowed by the power battery for the motor is determined according to the corrected maximum power allowed by the power battery for the motor, the energy conversion efficiency of the drive motor and the rotation speed of the drive motor.

2. The motor torque limiting method according to claim 1, characterized in that: Get the original value of the maximum torque allowed by the power battery, including: Obtaining the maximum power of the motor allowed by the power battery, the energy conversion efficiency of the drive motor, and the speed of the drive motor; An original value of the maximum torque allowed by the power battery for the motor is determined according to the maximum power allowed by the power battery for the motor, the energy conversion efficiency of the drive motor and the rotation speed of the drive motor.

3. The motor torque limiting method according to claim 1, characterized in that: Obtaining the expected power of the power battery includes: Acquiring historical requested motor torque, energy conversion efficiency of the drive motor, speed of the drive motor and power consumption of high-voltage accessories; The expected power of the power battery is determined according to the historical requested motor torque, the energy conversion efficiency of the drive motor, the rotation speed of the drive motor and the power consumption of the high-voltage accessories.

4. The motor torque limiting method according to any one of claims 1 to 3, characterized in that: When the operating condition of the power battery is a driving condition, obtaining the expected power and the actual power of the power battery includes: Obtain the expected discharge power and actual discharge power of the power battery; Determining torque correction data according to the actual power and the expected power includes: determining driving torque correction data according to the actual discharge power and the expected discharge power; Determining the limiting torque of the driving motor according to the torque correction data includes: The driving motor driving limit torque is determined based on the driving torque correction data.

5. The motor torque limiting method according to any one of claims 1 to 3, characterized in that: When the operating condition of the power battery is an energy recovery condition, obtaining the expected power and the actual power of the power battery includes: Obtain the expected recovery power and actual recovery power of the power battery; Determining torque correction data according to the actual power and the expected power includes: determining energy recovery torque correction data according to the actual recovery power and the expected recovery power; Determining the limiting torque of the driving motor according to the torque correction data includes: The driving motor recovery limit torque is determined according to the energy recovery torque correction data.

6. A motor torque limiting device, used to implement the steps of the motor torque limiting method according to any one of claims 1 to 5, characterized in that: include: A first acquisition module is used to acquire the expected power and actual power of the power battery; a first determination module, configured to determine torque correction data according to the actual power and the expected power if the actual power is greater than the expected power; A second determination module, configured to determine a limit torque of the drive motor according to the torque correction data; The torque limiting module is used to determine the requested motor torque according to the driving motor limited torque and the motor required torque.

7. A controller, characterized in that: include: Memory for storing computer programs; A processor, configured to implement the steps of the motor torque limiting method as claimed in any one of claims 1 to 5 when executing the computer program.

8. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the motor torque limiting method according to any one of claims 1 to 5 are implemented.

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