A method and system for extracting zero-crossing calibration parameters of motor torque in new energy vehicles

Abstract

This application provides a method and system for extracting zero-crossing calibration parameters for motor torque in new energy vehicles. The method includes: acquiring the motor output torque signal and motor speed signal when the vehicle performs rapid acceleration or deceleration; identifying the zero-crossing torque condition based on the motor output torque signal and extracting the moment of torque zero-crossing; determining the zero-crossing interval based on the moment of torque zero-crossing; extracting the final control point of zero-crossing control; extracting the final control point torque from the motor output torque signal; taking its negative value as the starting control point torque and extracting the corresponding moment; determining the time difference based on the starting control point moment and the final control point moment; determining the torque difference based on the starting control point torque and the final control point torque; determining the torque change rate based on the ratio of the torque difference to the time difference; and inputting the starting control point torque, the final control point torque, and the torque change rate into the vehicle calibration system. This application improves calibration accuracy and efficiency and solves the problem of unstable impact control performance in mass-produced vehicles.

Description

Technical Field

[0001] This application belongs to the field of new energy vehicle technology, and in particular relates to a method and system for extracting zero-crossing calibration parameters of motor torque for new energy vehicles. Background Technology

[0002] New energy vehicles often involve tip-in / tip-out (rapid acceleration / rapid deceleration) conditions, and the motor torque is very prone to zero crossing (changing from negative to positive or vice versa). In addition, due to the rotational clearance of the drive system (such as gear backlash and spline clearance), clunk problems can occur due to clearance reversal. Severe clunk usually manifests as a "clanging" sound. If not controlled, it will bring a bad driving experience to the occupants. Clunk control has become one of the key issues that automobile companies pay attention to when developing new cars.

[0003] Existing technologies mainly reduce the impact intensity during the commutation process by implementing zero-crossing control of motor torque. For example, CN118358366B—a method for determining and controlling the zero-crossing range of motor torque in new energy vehicles—proposes a method for determining the separation point and contact point of the clearance under the zero-crossing condition of motor torque, laying the foundation for reasonably estimating the zero-crossing range of torque and thus accurately implementing zero-crossing control. However, it does not consider the impact of product consistency on motor output torque and drive system clearance. Mass-produced vehicles use a fixed zero-crossing control strategy, which often results in unstable clunk control effects. Summary of the Invention

[0004] In view of this, this application aims to propose a method and system for extracting zero-crossing calibration parameters of motor torque for new energy vehicles, so as to solve at least one of the above problems.

[0005] To achieve the above objectives, the technical solution of this application is implemented as follows: Firstly, this application provides a method for extracting zero-crossing calibration parameters of motor torque in new energy vehicles, including: Acquire the motor output torque signal and motor speed signal when the vehicle performs rapid acceleration or deceleration, identify the torque zero crossing condition based on the motor output torque signal, and extract the torque zero crossing moment; Based on the torque zero-crossing time, the zero-crossing interval is determined, the final control point of the zero-crossing control is extracted, the final control point torque is extracted from the motor output torque signal, its opposite is taken as the starting control point torque and the corresponding time is extracted. The time difference is determined based on the start control point time and the end control point time. The torque difference is determined based on the start control point torque and the end control point torque. The torque change rate is determined based on the ratio of the torque difference to the time difference. The start control point torque, the end control point torque, and the torque change rate are then input into the vehicle calibration system.

[0006] Secondly, based on the same inventive concept, this application also provides a system for extracting zero-crossing calibration parameters for the motor torque of a new energy vehicle, comprising: The first extraction module is configured to acquire the motor output torque signal and motor speed signal when the vehicle performs rapid acceleration or deceleration, identify the torque zero crossing condition based on the motor output torque signal, and extract the torque zero crossing moment. The second extraction module is configured to determine the zero-crossing interval based on the torque zero-crossing time, extract the final control point of the zero-crossing control, extract the final control point torque from the motor output torque signal, take its opposite as the starting control point torque and extract the corresponding time. The calibration input module is configured to determine the time difference based on the start control point time and the end control point time, determine the torque difference based on the start control point torque and the end control point torque, determine the torque change rate based on the ratio of the torque difference to the time difference, and input the start control point torque, the end control point torque, and the torque change rate to the vehicle calibration system.

[0007] Thirdly, based on the same inventive concept, this application also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the method described in the first aspect.

[0008] Fourthly, based on the same inventive concept, this application also provides a non-transitory computer-readable storage medium, wherein the non-transitory computer-readable storage medium stores computer instructions for causing the computer to perform the method as described in the first aspect.

[0009] Compared with existing technologies, the method and system for extracting zero-crossing calibration parameters of motor torque for new energy vehicles described in this application have the following advantages: The method for extracting zero-crossing calibration parameters of motor torque of new energy vehicles described in this application can automatically extract parameters such as the starting point, ending point and zero-crossing slope required for torque zero-crossing control, thereby improving calibration accuracy and efficiency. The goal is to ensure that each vehicle has good control effect under Tip-in or Tip-out conditions. Attached Figure Description

[0010] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. In the drawings: Figure 1 This is a flowchart illustrating a method for extracting zero-crossing calibration parameters for a new energy vehicle motor, as described in an embodiment of this application. Figure 2This is a schematic diagram illustrating the synchronous acquisition of motor output torque signal, motor speed signal, and half-shaft torque signal as described in an embodiment of this application. Figure 3(a) is a schematic diagram of the signal change trend curve under the rapid acceleration condition described in the embodiment of this application; Figure 3(b) is a schematic diagram of the signal change trend curve under the rapid deceleration condition described in the embodiment of this application; Figure 4 This is a schematic diagram of a new energy vehicle motor torque zero-crossing calibration parameter extraction system according to an embodiment of this application; Figure 5 This is a schematic diagram of the hardware structure of the electronic device described in an embodiment of this application. Detailed Implementation

[0011] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with specific embodiments and the accompanying drawings.

[0012] It should be noted that, unless otherwise defined, the technical or scientific terms used in the embodiments of this application should have the ordinary meaning understood by one of ordinary skill in the art to which this application pertains. The terms "first," "second," and similar terms used in the embodiments of this application do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are only used to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0013] The embodiments of this application are described in detail below with reference to the accompanying drawings.

[0014] Please see Figure 1 As shown in the figure, this embodiment provides a method for extracting zero-crossing calibration parameters of motor torque in new energy vehicles, which specifically includes the following steps: Step S101: Obtain the motor output torque signal and motor speed signal when the vehicle performs rapid acceleration or deceleration. Identify the torque zero-crossing condition based on the motor output torque signal and extract the torque zero-crossing moment. Step S102: Determine the zero-crossing interval based on the torque zero-crossing time, extract the final control point of the zero-crossing control, extract the final control point torque from the motor output torque signal, take its opposite as the starting control point torque and extract the corresponding time. Step S103: Determine the time difference based on the start control point time and the end control point time, determine the torque difference based on the start control point torque and the end control point torque, determine the torque change rate based on the ratio of the torque difference to the time difference, and input the start control point torque, the end control point torque, and the torque change rate into the vehicle calibration system.

[0015] The method described in this embodiment can automatically identify the zero-crossing torque condition of the motor and automatically extract the calibration parameters for the zero-crossing torque condition (parameters such as the gap separation point, contact point torque, and torque change rate). It inputs the zero-crossing torque start point (gap separation point), end point (gap contact point) torque, and torque change rate into the calibration system and updates the calibration strategy. It evaluates whether the power performance and NVH performance meet the requirements, iterating until the requirements are met, then locking the strategy and implementing it. This technique improves calibration accuracy and efficiency and creates a unique set of zero-crossing torque control parameters for each vehicle, solving the problem of unstable clunk control performance in mass-produced vehicles.

[0016] In some implementations, the torque zero-crossing time corresponding to the zero torque value is obtained based on the motor output torque signal, and the torque value is retrieved in a first interval range and a second interval range set with the torque zero-crossing time as the node; wherein, the first interval range and the second interval range constitute the zero-crossing interval; If all data in the first interval is less than the preset value and all data in the second interval is greater than or equal to the preset value, then it is determined to be a rapid acceleration condition. If all data in the first interval is greater than the preset value, and all data in the second interval is less than or equal to the preset value, then the condition is determined to be a rapid deceleration condition.

[0017] Specifically, in this embodiment, the vehicle performs Tip-in or Tip-out operations, and simultaneously collects the vibration signal of the electric drive assembly and the motor output torque signal. Based on the motor output torque signal, the torque zero-crossing condition is automatically identified, and the moment of torque zero-crossing is extracted. The moment corresponding to the torque "0" value is obtained by the motor output torque signal. Then forward respectively and backward Retrieve torque value, if All data within the range are <0, and If all data within the range are ≥0, then this is considered a Tip-in condition; if All data within the range are >0, and If all data within the range are ≤0, then the condition is determined to be Tip out.

[0018] In some implementations, the methods for retrieving start and end control points include: Within the zero-crossing interval, the motor speed signal is retrieved, and the time corresponding to the maximum motor speed under rapid acceleration and the minimum motor speed under rapid deceleration are extracted as the final control point of the zero-crossing control. The final control point torque is extracted from the motor output torque signal, and its negative number is taken as the starting control point torque and the corresponding time is extracted.

[0019] In some implementations, the time difference is determined based on the start control point time and the end control point time, the torque difference is determined based on the start control point torque and the end control point torque, and the torque change rate is determined based on the ratio of the torque difference to the time difference. The final control point is the moment corresponding to the maximum value (rapid acceleration condition) or minimum value (rapid deceleration condition) of the motor speed signal within the second interval, and the starting control point is the moment corresponding to the value opposite to the final control point torque within the first interval.

[0020] Specifically, in this embodiment, based on the impact signal characteristics formed at the gap separation moment and the gap contact moment, the final control point time is... The time corresponding to the maximum value (rapid acceleration condition) or minimum value (rapid deceleration condition) of the motor speed signal within the range. Utilizing the final control point time Extract the final control point torque from the motor output torque signal. Take the value opposite to the final control point torque as the starting control point torque. (- ), and output torque signal from the motor. Search within range Corresponding start control point time .

[0021] The time difference is determined using the start and end control points, and the torque difference is determined based on the start and end control torques. Simultaneously, the torque change rate is automatically calculated. After automatically updating the zero-crossing calibration strategy, the dynamic performance and NVH performance are further evaluated, with the goal of ensuring that the clunk conditions of Tip-in and Tip-out for each vehicle have good control.

[0022] Figure 2Figure 3 shows a partial enlarged view of the Tipin and Tipout operating conditions, which synchronously collects the motor output torque signal, motor speed signal, and half-shaft torque signal. As shown in Figure 3(a), the time corresponding to the torque "0" value obtained from the motor output torque signal is 14.267s. Through signal feature analysis, it is determined to be the Tipin operating condition. The time corresponding to the maximum value of the motor speed signal in the range of 14.267~14.467s is extracted to be 14.382s, which is the final control point time. The torque corresponding to 14.382s is extracted from the motor torque signal to be 5.5Nm, which is the final control point torque. The opposite value of the final control point torque, -5.5Nm, is taken as the starting control point torque. At the same time, the time corresponding to -5.5Nm in the motor torque signal in the range of 14.067~14.267s is retrieved to be 14.168s, which is the starting control point time.

[0023] As shown in Figure 3(b), the time corresponding to the torque "0" value obtained from the motor output torque signal is 16.228s. Through signal feature analysis, it is determined to be a Tip-out condition. The time corresponding to the minimum value of the motor speed signal in the range of 16.228~16.428s is 16.322s, which is the final control point time. The torque corresponding to 16.322s is extracted from the motor torque signal as -2.8Nm, which is the final control point torque. The opposite value of the final control point torque, 2.8Nm, is taken as the starting control point torque. At the same time, the time corresponding to 2.8Nm in the motor torque signal in the range of 16.028~16.228s is 16.197s, which is the starting control point time.

[0024] Observation of the half-shaft torque signal obtained by the torque sensor shows that the plateau segment where the torque signal approaches zero is the zero-crossing process of the shaft system. The torque zero-crossing control strategy formed by the above method can completely cover the zero-crossing process of the shaft system. The time difference is determined by using the start control point and the end control point, and the torque difference is determined by the start control point torque and the end control point torque. The torque change rate is calculated, and the results are shown in Table 1.

[0025] Table 1 Calibration Parameter Table It should be noted that the above description describes some embodiments of this application. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recorded in the claims can be performed in a different order than that shown in the above embodiments and still achieve the desired result. Furthermore, the processes depicted in the drawings do not necessarily require a specific or sequential order to achieve the desired result. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0026] Based on the same inventive concept, corresponding to the methods of any of the above embodiments, embodiments of this application also provide a system for extracting zero-crossing calibration parameters of motor torque for new energy vehicles, such as... Figure 4 As shown, it includes: The first extraction module 11 is configured to acquire the motor output torque signal and motor speed signal when the vehicle performs rapid acceleration or deceleration, identify the torque zero crossing condition based on the motor output torque signal, and extract the torque zero crossing moment. The second extraction module 12 is configured to determine the zero-crossing interval based on the torque zero-crossing time, extract the final control point of the zero-crossing control, extract the final control point torque from the motor output torque signal, take its opposite number as the starting control point torque and extract the corresponding time. The calibration input module 13 is configured to determine the time difference based on the start control point time and the end control point time, determine the torque difference based on the start control point torque and the end control point torque, determine the torque change rate based on the ratio of the torque difference to the time difference, and input the start control point torque, the end control point torque and the torque change rate to the vehicle calibration system.

[0027] The automatic extraction system for motor torque zero-crossing control calibration parameters mainly consists of a device that communicates with the CAN bus and an automatic extraction program for calibration parameters (which runs the method described in the above embodiment). The motor output torque signal and motor speed signal are introduced into the automatic extraction program for zero-crossing calibration parameters. After signal processing and calculation, the program automatically extracts parameters such as the starting control point, ending control point, and zero-crossing slope required for torque zero-crossing control, improving calibration accuracy and efficiency. The goal is to ensure good control performance for each vehicle during Tip-in or Tip-out clunk conditions.

[0028] For ease of description, the above system is described by dividing it into various modules based on their functions. Of course, in implementing the embodiments of this application, the functions of each module can be implemented in one or more software and / or hardware.

[0029] The system described in the above embodiments is used to implement the corresponding method in any of the foregoing embodiments and has the beneficial effects of the corresponding method embodiments, which will not be repeated here.

[0030] Based on the same inventive concept, corresponding to the methods of any of the above embodiments, embodiments of this application also provide an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the methods described in any of the above embodiments.

[0031] Figure 5This embodiment illustrates a more specific hardware structure of an electronic device, which may include a processor 1010, a memory 1020, an input / output interface 1030, a communication interface 1040, and a bus 1050. The processor 1010, memory 1020, input / output interface 1030, and communication interface 1040 are interconnected internally via the bus 1050.

[0032] The processor 1010 can be implemented using a general-purpose CPU (Central Processing Unit), microprocessor, application-specific integrated circuit (ASIC), or one or more integrated circuits, and is used to execute relevant programs to implement the technical solutions provided in the embodiments of this specification.

[0033] The memory 1020 can be implemented in the form of ROM (Read Only Memory), RAM (Random Access Memory), static storage device, dynamic storage device, etc. The memory 1020 can store the operating system and other applications. When the technical solutions provided in the embodiments of this specification are implemented by software or firmware, the relevant program code is stored in the memory 1020 and is called and executed by the processor 1010.

[0034] The input / output interface 1030 is used to connect input / output modules to realize information input and output. The input / output modules can be configured as components in the device (not shown in the figure) or externally connected to the device to provide corresponding functions. Input devices may include keyboards, mice, touch screens, microphones, various sensors, etc., and output devices may include displays, speakers, vibrators, indicator lights, etc.

[0035] The communication interface 1040 is used to connect a communication module (not shown in the figure) to enable communication between this device and other devices. The communication module can communicate via wired means (such as USB, Ethernet cable, etc.) or wireless means (such as mobile network, WIFI, Bluetooth, etc.).

[0036] Bus 1050 includes a pathway for transmitting information between various components of the device, such as processor 1010, memory 1020, input / output interface 1030, and communication interface 1040.

[0037] It should be noted that although the above-described device only shows the processor 1010, memory 1020, input / output interface 1030, communication interface 1040, and bus 1050, in specific implementations, the device may also include other components necessary for normal operation. Furthermore, those skilled in the art will understand that the above-described device may only include the components necessary for implementing the embodiments of this specification, and not necessarily all the components shown in the figures.

[0038] The electronic devices described above are used to implement the corresponding methods in any of the foregoing embodiments and have the beneficial effects of the corresponding method embodiments, which will not be repeated here.

[0039] Based on the same inventive concept, corresponding to the methods of any of the above embodiments, this application also provides a non-transitory computer-readable storage medium that stores computer instructions for causing the computer to perform the methods described in any of the above embodiments.

[0040] The computer-readable medium of this embodiment includes permanent and non-permanent, removable and non-removable media, and information storage can be implemented by any method or technology. Information can be computer-readable instructions, data structures, program modules, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other non-transfer medium that can be used to store information accessible by a computing device.

[0041] The computer instructions stored in the storage medium of the above embodiments are used to cause the computer to perform the method described in any of the above embodiments, and have the beneficial effects of the corresponding method embodiments, which will not be repeated here.

[0042] Those skilled in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of this application (including the claims) is limited to these examples; within the framework of this application, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of different aspects of the embodiments of this application as described above, which are not provided in the details for the sake of brevity.

[0043] Although this application has been described in conjunction with specific embodiments thereof, many substitutions, modifications, and variations of these embodiments will be apparent to those skilled in the art from the foregoing description. For example, other memory architectures (e.g., dynamic RAM (DRAM)) may be used with the embodiments discussed.

[0044] The embodiments of this application are intended to cover all such substitutions, modifications, and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the embodiments of this application should be included within the protection scope of this application.

Claims

1. A method for extracting zero-crossing calibration parameters of motor torque in new energy vehicles, characterized in that, include: Acquire the motor output torque signal and motor speed signal when the vehicle performs rapid acceleration or deceleration, identify the torque zero crossing condition based on the motor output torque signal, and extract the torque zero crossing moment; Based on the torque zero-crossing time, the zero-crossing interval is determined, the final control point of the zero-crossing control is extracted, the final control point torque is extracted from the motor output torque signal, its opposite is taken as the starting control point torque and the corresponding time is extracted. The time difference is determined based on the start control point time and the end control point time. The torque difference is determined based on the start control point torque and the end control point torque. The torque change rate is determined based on the ratio of the torque difference to the time difference. The start control point torque, the end control point torque, and the torque change rate are then input into the vehicle calibration system.

2. The method according to claim 1, characterized in that: The zero-crossing moment of the torque corresponding to the zero torque value is obtained based on the output torque signal of the motor, and the torque value is retrieved in a first interval range and a second interval range set with the zero-crossing moment of the torque as the node; wherein, the first interval range and the second interval range constitute the zero-crossing interval; If all data in the first interval is less than the preset value, and all data in the second interval is greater than or equal to the preset value, then it is determined to be a rapid acceleration condition. If all data within the first interval is greater than a preset value, and all data within the second interval is less than or equal to the preset value, then the condition is determined to be a rapid deceleration condition.

3. The method according to claim 1, characterized in that: in, The final control point time is the time corresponding to the maximum motor speed under rapid acceleration and the time corresponding to the minimum motor speed under rapid deceleration.

4. A system for extracting zero-crossing calibration parameters for motor torque in new energy vehicles, characterized in that, include: The first extraction module is configured to acquire the motor output torque signal and motor speed signal when the vehicle performs rapid acceleration or deceleration, identify the torque zero crossing condition based on the motor output torque signal, and extract the torque zero crossing moment. The second extraction module is configured to determine the zero-crossing interval based on the torque zero-crossing time, extract the final control point of the zero-crossing control, extract the final control point torque from the motor output torque signal, take its opposite as the starting control point torque and extract the corresponding time. The calibration input module is configured to determine the time difference based on the start control point time and the end control point time, determine the torque difference based on the start control point torque and the end control point torque, determine the torque change rate based on the ratio of the torque difference to the time difference, and input the start control point torque, the end control point torque, and the torque change rate to the vehicle calibration system.

5. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the method as described in any one of claims 1-3.

6. A non-transitory computer-readable storage medium, characterized in that, in, The non-transitory computer-readable storage medium stores computer instructions for causing a computer to perform the method described in any one of claims 1-3.

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