Motor zero point calibration method, device, equipment, storage medium and product

Abstract

The present application discloses a motor zero-point calibration method, device, equipment, storage medium and product, which relates to the technical field of electric vehicles. The method includes: detecting the current gear working condition of the vehicle, and when the gear working condition is detected to be a gear shifting condition, controlling each motor to enter a speed control mode, obtaining the output torque corresponding to each motor, determining the theoretical torque corresponding to each motor based on the energy balance principle, and obtaining the torque deviation value corresponding to each motor by comparing the output torque and theoretical torque of each motor. The maximum deviation value is selected from the torque deviation values ​​corresponding to each motor, and when the maximum deviation value reaches the preset deviation threshold, a zero-point deviation warning is issued. By comparing and evaluating the torque output of the motor during gear shifting, the motor installed on the vehicle is calibrated at zero point. When the deviation of the motor zero-point calibration result is large, an alarm is actively issued to ensure the safety of passengers during vehicle operation and improve the driving experience.

Description

Technical Field

[0001] The present application relates to the technical field of electric vehicles, and in particular to motor zero-point calibration methods, devices, equipment, storage media and products. Background Art

[0002] As an important driving component of pure electric vehicles, permanent magnet synchronous motors have high requirements for torque, speed regulation, power density, efficiency, etc. At present, automotive permanent magnet synchronous motors mainly use vector control to achieve direct and quadrature axis current decoupling. During the control process, the current needs to be transformed by Clarke, Park and inverse transformation, and the core of the coordinate transformation is the detection of the motor rotor position angle.

[0003] At present, the motor zero point detection is often carried out on a test bench or before the motor leaves the factory, and compensation is performed. It is difficult to disassemble the motor after it is installed on the vehicle or delivered. Since the motor zero point detection is a passive operation, pure electric vehicles cannot actively sense and warn when there is a large deviation in the motor zero point, and users can only sense it when the zero point deviation causes a reduction in driving experience.

[0004] Therefore, how to detect the motor zero point deviation in time is a problem that needs to be solved urgently. Summary of the invention

[0005] The main purpose of this application is to provide a motor zero point calibration method, device, equipment, storage medium and product, aiming to solve the technical problem of timely detecting motor zero point deviation.

[0006] To achieve the above purpose, the present application proposes a motor zero point calibration method, the method comprising:

[0007] Detect the current gear position of the vehicle;

[0008] When it is detected that the gear position working condition is a gear shift working condition, each motor is controlled to enter a speed control mode to obtain an output torque corresponding to each motor;

[0009] Determine the theoretical torque corresponding to each of the motors based on the energy balance principle, compare the output torque of each of the motors with the theoretical torque, and obtain a torque deviation value corresponding to each of the motors;

[0010] A maximum deviation value is selected from the torque deviation values ​​corresponding to the motors, and when the maximum deviation value reaches a preset deviation threshold, a zero point deviation warning is issued.

[0011] In one embodiment, the output torque includes a shift output torque, and when the gear operating condition is detected to be a shift operating condition, the step of controlling each motor to enter a speed control mode to obtain the output torque corresponding to each motor includes:

[0012] When it is detected that the vehicle operating condition changes from neutral to a target gear, the target motor speed is calculated according to the target vehicle speed corresponding to the target gear;

[0013] The motor speed is controlled to the target motor speed to obtain the shift output torque corresponding to each motor.

[0014] In one embodiment, the step of determining the theoretical torque corresponding to each of the motors based on the energy balance principle, comparing the output torque of each of the motors with the theoretical torque, and obtaining the torque deviation value corresponding to each of the motors includes:

[0015] Calculating a theoretical torque according to the target motor speed, the current vehicle speed and the rotational inertia of the corresponding motor;

[0016] The output torque of each of the motors is compared with the theoretical torque to obtain a torque deviation value corresponding to each of the motors.

[0017] In one embodiment, after the step of controlling the motor speed to the target motor speed and obtaining the shift output torque corresponding to each motor, the step further includes:

[0018] Comparing the shift output torques corresponding to the motors to obtain a set of shift deviation values ​​between the motors;

[0019] Selecting the maximum deviation value in the gear shift deviation value set;

[0020] When the maximum deviation value reaches a preset deviation threshold, a zero point deviation warning is issued.

[0021] In one embodiment, the step of calculating the theoretical torque according to the target motor speed, the current vehicle speed and the rotational inertia of the corresponding motor, the theoretical torque calculation formula is expressed as:

[0022]

[0023] In the above formula, represents the theoretical torque, Indicates the inertia coefficient of the corresponding motor, Indicates the moment of inertia of the corresponding motor, represents pi, Indicates the shift time interval, The speed change is the difference between the target motor speed and the current vehicle speed.

[0024] In one embodiment, after the step of detecting the current gear position of the vehicle, the following steps are included:

[0025] When the gear position is detected to be in neutral, the motor speed is controlled to the current vehicle speed to obtain the neutral output torque of each motor;

[0026] Comparing the neutral output torques corresponding to the motors to obtain a set of neutral deviation values ​​between the motors;

[0027] Selecting the maximum deviation value in the neutral deviation value set;

[0028] When the maximum deviation value reaches a preset deviation threshold, a zero point deviation warning is issued.

[0029] In addition, to achieve the above-mentioned purpose, the present application also proposes a motor zero point calibration device, the motor zero point calibration device comprising:

[0030] A working condition detection module, used to detect the current gear working condition of the vehicle;

[0031] The torque output module is used to control each motor to enter a speed control mode when the gear position working condition is detected to be a gear shift working condition, so as to obtain the output torque corresponding to each motor;

[0032] a deviation calculation module, used to determine the theoretical torque corresponding to each of the motors based on the energy balance principle, compare the output torque of each of the motors with the theoretical torque, and obtain a torque deviation value corresponding to each of the motors;

[0033] The deviation warning module is used to select a maximum deviation value from the torque deviation values ​​corresponding to each of the motors, and issue a zero point deviation warning when the maximum deviation value reaches a preset deviation threshold.

[0034] In addition, to achieve the above-mentioned purpose, the present application also proposes a motor zero-point calibration device, which includes: a memory, a processor, and a computer program stored in the memory and executable on the processor, and the computer program is configured to implement the steps of the motor zero-point calibration method described above.

[0035] In addition, to achieve the above-mentioned purpose, the present application also proposes a storage medium, which is a computer-readable storage medium, and a computer program is stored on the storage medium. When the computer program is executed by the processor, the steps of the motor zero point calibration method described above are implemented.

[0036] In addition, to achieve the above-mentioned purpose, the present application also provides a computer program product, which includes a computer program, and when the computer program is executed by a processor, the steps of the motor zero point calibration method described above are implemented.

[0037] One or more technical solutions proposed in this application have at least the following technical effects:

[0038] Detect the current gear condition of the vehicle. When it is detected that the gear condition is a gear shift condition, control each motor to enter the speed control mode, obtain the output torque corresponding to each motor, determine the theoretical torque corresponding to each motor based on the energy balance principle, and obtain the torque deviation value corresponding to each motor by comparing the output torque and theoretical torque of each motor. Select the maximum deviation value from the torque deviation values ​​corresponding to each motor. When the maximum deviation value reaches the preset deviation threshold, issue a zero-point deviation warning. By comparing and evaluating the torque output of the motor during gear shifting, the zero-point calibration of the motor installed on the vehicle is performed. Actively issue an alarm when the deviation of the motor zero-point calibration result is large to ensure the safety of passengers during vehicle operation and improve the driving experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0040] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0041] Figure 1 A schematic diagram of a motor current vector according to an embodiment of the present application;

[0042] Figure 2 This is a flow chart of the first embodiment of the motor zero point calibration method of the present application;

[0043] Figure 3 This is a flow chart of an implementation method of the present application;

[0044] Figure 4 A schematic diagram of the change in motor speed according to an embodiment of the present application;

[0045] Figure 5 This is a flow chart of another implementation method of the present application;

[0046] Figure 6 This is a flow chart of the second embodiment of the motor zero point calibration method of the present application;

[0047] Figure 7 A schematic diagram of the motor speed control process according to an embodiment of the present application;

[0048] Figure 8 This is a schematic diagram of the module structure of the motor zero point calibration device according to an embodiment of the present application;

[0049] Fig. 9This is a schematic diagram of the device structure of the hardware operating environment involved in the motor zero-point calibration method of the embodiment of the present application.

[0050] The purpose, features and advantages of this application will be further described in conjunction with the embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0051] It should be understood that the specific embodiments described herein are only used to explain the technical solutions of the present application and are not used to limit the present application.

[0052] In order to better understand the technical solution of the present application, a detailed description will be given below in conjunction with the accompanying drawings and specific implementation methods.

[0053] It should be noted that after the motor is designed and manufactured, there is a mechanical zero point, which is defined as the position of the rotor when the α-axis and d-axis of the motor coincide. Figure 1 As shown, Figure 1 is the motor current vector diagram, S is defined as the north pole of the permanent magnet synchronous motor rotor magnetic pole, N is defined as the south pole of the permanent magnet synchronous motor rotor magnetic pole, d-axis is defined as the N-pole direction of the permanent magnet synchronous motor rotor magnetic pole, q-axis is defined as the direction of 90° counterclockwise rotation from the positive direction of d-axis, α and β axes are two-phase stationary coordinate system obtained by clack coordinate transformation based on three-phase stationary coordinate system. The three-phase current vector of the motor is projected to α on the three-phase coordinate system after clack coordinate transformation. In the coordinate system, Expressed as the current vector projected onto the α frame, Expressed as a voltage vector projected onto the α frame, Represented as a projection onto The current vector on the reference system, Represented as a projection onto The resolver angle is the position signal of the resolver sensor. When the resolver zero point coincides with the motor mechanical zero point or after zero point compensation, it can be expressed as follows: Figure 1 The angle between the α axis and the d axis .

[0054] A resolver is an electromagnetic sensor that is commonly used to measure angular position and speed. Through two sets of coupled stator and rotor coils, it can convert the input sinusoidal excitation signal into an amplitude modulated output signal that has a positive and cosine function relationship with the rotor angle. The motor rotor position signal can be obtained by decoding the output signal through a phase-locked loop or other methods. The decoded AD value is generally set in the range of 0-4095, where the rotor position corresponding to the value of 0 is the zero point of the resolver. Due to design, assembly and other reasons, the motor zero point and the resolver zero point do not correspond accurately. At this time, when the motor rotor position is 0, the resolver position is often another value. , which is the zero-point deflection angle of the resolver. For this purpose, a compensation value needs to be set in the software , the position of the resolver is compensated to zero point, and the relationship is:

[0055]

[0056] Here, 4096 is the AD value range after output voltage decoding set by the resolver sensor manufacturer, which may be different for different products. The zero-point deviation of the motor has a great influence on its torque output. When the zero-point deviation of the resolver is offset by ±2 electrical degrees, the motor output torque will have an error of about ±3Nm in the low-speed non-weak magnetic zone and an error of about ±8Nm in the high-speed weak magnetic zone.

[0057] Since the motor rotor position detection often uses a resolver, it is an electromagnetic sensor that can convert a sinusoidal excitation signal into an amplitude modulated signal with a sine and cosine function relationship, and obtain a position signal through decoding. It is often used to measure angular position and speed. The zero point of the motor is generally given during design, and the zero point of the resolver is also given during its design and production, but there is a certain deviation between the two due to motor manufacturing, resolver assembly and other reasons. The motor zero point deviation will affect the performance of the motor, for example, it will cause vibration and noise at the start of the motor, and reduce the efficiency and accuracy of the motor. Therefore, in order to ensure the torque accuracy and efficiency of the motor, reduce noise, and improve the performance and reliability of the motor, the motor resolver zero point detection and calculation has become an important test item in motor control. As a device for detecting angular displacement and speed, the resolver converts the displacement into a voltage signal output, and obtains the position signal through phase-locked loop decoding. According to its principle, it can only detect the zero point of the resolver itself. There is a sine and cosine relationship between the resolver output voltage and the rotor angle, so the output voltage overlimit does not indicate a problem with the motor rotor zero point, but can only be judged that there may be a problem with the resolver itself. When the resolver zero point coincides with the motor zero point, the motor mechanical zero point can be reflected. At present, the main method for motor zero point deviation is to perform zero point calibration compensation before the motor leaves the factory. This requires a single motor to be tested on a bench or production line to obtain a compensation value. And written into the software; after the motor is installed on the vehicle, there is a lack of corresponding detection conditions. When the zero point of the motor changes due to factors such as vehicle vibration and installation error, that is, The value changes, and the zero point deviation cannot be determined only by the position information read by the resolver. In addition, under the current torque control algorithm, it is difficult to determine the deviation of the motor resolver zero point only by the output torque and speed deviation, and it is impossible to rule out the influence of other factors such as road conditions, driving mode, resonance, etc.

[0058] The present application provides a solution to detect the current gear working condition of the vehicle. When it is detected that the gear working condition is a gear shifting working condition, each motor is controlled to enter a speed control mode to obtain the output torque corresponding to each motor, and the theoretical torque corresponding to each motor is determined based on the energy balance principle. By comparing the output torque of each motor with the theoretical torque, the torque deviation value corresponding to each motor is obtained. The maximum deviation value is selected from the torque deviation values ​​corresponding to each motor, and when the maximum deviation value reaches the preset deviation threshold, a zero deviation warning is issued. By comparing and evaluating the torque output of the motor during gear shifting, the zero point of the motor installed on the vehicle is calibrated.

[0059] Based on this, the present application embodiment provides a motor zero point calibration method, referring to Figure 2 , Figure 2 This is a flow chart of the first embodiment of the motor zero point calibration method of the present application.

[0060] In this embodiment, the motor zero point calibration method includes steps S10 to S40:

[0061] Step S10, detecting the current gear position of the vehicle.

[0062] It should be noted that the gear operating condition may refer to the current gear state of the vehicle, such as parking gear (P), reverse gear (R), neutral gear (N), driving gear (D), etc., and the switching process between these gears. For example, the current gear operating condition of the vehicle may be determined by reading the sensor signal of the vehicle transmission system.

[0063] Step A20, when it is detected that the gear position condition is a gear shift condition, each motor is controlled to enter a speed control mode to obtain the output torque corresponding to each motor.

[0064] It should be noted that the speed control mode can be understood as a motor control mode, which can output the required torque or power by adjusting the speed of the motor. For example, when the vehicle switches from a stationary state to a driving state, it is necessary to control the drive motor to output sufficient torque to overcome static friction and accelerate the vehicle.

[0065] Step A30, determining the theoretical torque corresponding to each motor based on the energy balance principle, comparing the output torque of each motor with the theoretical torque, and obtaining the torque deviation value corresponding to each motor.

[0066] It should be noted that the energy balance principle can be understood as that under ideal conditions, the energy input of the motor is equal to the energy output, that is, the energy obtained by the motor from the power supply is completely converted into mechanical energy without any loss. Exemplarily, when the rotational inertia of the motor is the same, the corresponding speed torque integral is the same. When the speed and torque integrals of multiple motors are the same, it means that they produce the same total rotational work in the same time. The theoretical torque can be the torque value that the motor should output calculated according to the energy balance principle to meet the current driving needs of the vehicle. The output torque can be the torque value actually output by the motor, which is the rotational torque generated by the motor under specific working conditions. It can be understood that the torque deviation value is the difference between the output torque of the motor and the theoretical torque, reflecting the difference between the actual output of the motor and the expected output.

[0067] Step A40, selecting a maximum deviation value from the torque deviation values ​​corresponding to each motor, and issuing a zero point deviation warning when the maximum deviation value reaches a preset deviation threshold.

[0068] It should be noted that the preset deviation threshold is a maximum allowable deviation range set according to vehicle design and performance requirements. The zero-point deviation warning can be understood as a warning issued when the torque deviation value of the motor exceeds the preset range. The warning indicates that there may be control or mechanical problems.

[0069] For example, if the torque deviation value of a motor exceeds the range of ±5% (assuming it is a preset deviation threshold), it may indicate that there is a control problem or mechanical failure in the motor, and a warning should be issued and maintenance should be performed.

[0070] In this embodiment, the current gear working condition of the vehicle is detected. When it is detected that the gear working condition is a gear shifting condition, each motor is controlled to enter a speed control mode to obtain the output torque corresponding to each motor. The theoretical torque corresponding to each motor is determined based on the energy balance principle. By comparing the output torque of each motor with the theoretical torque, the torque deviation value corresponding to each motor is obtained. The maximum deviation value is selected from the torque deviation values ​​corresponding to each motor. When the maximum deviation value reaches the preset deviation threshold, a zero point deviation warning is issued. By comparing and evaluating the torque output of the motor during gear shifting, the zero point of the motor installed on the vehicle is calibrated. When the deviation of the motor zero point calibration result is large, an alarm is actively issued to ensure the safety of passengers during vehicle operation and improve the driving experience.

[0071] In one embodiment, referring to Figure 3 , Figure 3 This is a flowchart of a specific implementation method of the first embodiment of the motor zero point calibration method of the present application, wherein step A20 includes steps A201-A202:

[0072] Step A201, when it is detected that the vehicle operating condition changes from neutral to a target gear, a target motor speed is calculated according to a target vehicle speed corresponding to the target gear.

[0073] It should be noted that the neutral gear may be a gear position of the vehicle gearbox, in which the power of the motor will not be transmitted to the wheels. It is understandable that the vehicle state corresponding to the neutral gear in this embodiment may be free sliding or stationary. The target gear position may be the next gear position selected by the driver through the gear shift operation or the vehicle automatic transmission system. The target vehicle speed is the expected vehicle speed calculated by the system based on the target gear position and the current driving conditions (such as road conditions, vehicle load, etc.). The target motor speed refers to the rotation speed that the motor needs to reach in order to achieve the target vehicle speed.

[0074] Exemplarily, the system monitors the status of the vehicle in real time through sensors (such as gear position sensors, vehicle speed sensors, etc.). When it is detected that the gear position changes from neutral to a specific gear position (such as D gear, S gear, etc.), the system calculates the target vehicle speed through a preset algorithm or table lookup method based on the target gear position and current driving conditions (such as the driver's acceleration intention, vehicle load, road conditions, etc.), and calculates the target speed that the motor needs to reach through a formula based on parameters such as the target vehicle speed, the vehicle's transmission ratio (transmission gear ratio, final reduction ratio, etc.), and wheel radius.

[0075] Step A202, controlling the motor speed to a target motor speed, and obtaining the shift output torque corresponding to each motor.

[0076] It should be noted that the gear shift output torque can be understood as the torque value corresponding to the output when the vehicle gear is shifted to the target gear.

[0077] For example, Figure 4 As shown, the system sends instructions to the motor through the motor controller (such as an inverter) to change from gear 1 to gear 2, and adjusts the voltage and current of the motor so that the motor speed gradually approaches and stabilizes at the target motor speed. In this process, a closed-loop control strategy, such as PID control, may be used to accurately control the motor speed. While the motor speed is being adjusted, the system calculates the torque value that should be output during the gear shifting process based on the current speed, target speed, and torque characteristics of the motor. Furthermore, for vehicles driven by multiple motors, the system needs to reasonably allocate the output torque of each motor based on the characteristics of each motor and the dynamic requirements of the vehicle.

[0078] In this embodiment, when it is detected that the vehicle operating condition changes from neutral to the target gear, the target motor speed is calculated according to the target vehicle speed corresponding to the target gear, and the motor speed is controlled to the target motor speed to obtain the shift output torque corresponding to each motor. By reasonably allocating the output torque of each motor according to the characteristics of multiple motors and vehicle requirements, the optimal driving effect and energy utilization can be achieved.

[0079] In one embodiment, reference Figure 5 , Figure 5 This is a flow chart of another implementation of the first embodiment of the motor zero point calibration method of the present application, wherein step A30 includes steps A301-A302:

[0080] Step A301, calculating the theoretical torque according to the target motor speed, the current vehicle speed and the rotational inertia of the corresponding motor.

[0081] It should be noted that the theoretical torque calculation formula is expressed as formula (1):

[0082]

[0083] In formula (1), represents the theoretical torque, represents the inertia coefficient of the corresponding motor (for example, You can take 15), Indicates the moment of inertia of the corresponding motor, represents pi, Indicates the shift time interval, Indicates the speed change, which is the difference between the target motor speed and the current vehicle speed. Among them, the inertia coefficient can be used to adjust or standardize the coefficient of the influence of the motor's rotational inertia on the torque calculation. The rotational inertia is the property of an object to resist changing its rotational state when rotating. For a motor, the rotational inertia reflects the torque required by the motor rotor to change the speed. The shift time interval can be the time period from the current vehicle speed to the time required for the motor to reach the target speed.

[0084] Step A302, comparing the output torque of each motor with the theoretical torque to obtain the torque deviation value corresponding to each motor.

[0085] Exemplarily, the target motor speed, the current vehicle speed (if the current vehicle speed is used in the formula, otherwise it may be the current motor speed), the motor's moment of inertia and inertia coefficient are obtained, and the above parameters are substituted into the theoretical torque calculation formula to obtain the theoretical torque value through calculation. The actual output torque value of each motor under the current working condition is obtained through the motor controller or related sensors, and the actual output torque of each motor is compared with its corresponding theoretical torque to calculate the difference, that is, the torque deviation value. Analyze the torque deviation value to evaluate the accuracy and efficiency of the motor control. If the deviation is large, it may be necessary to adjust the motor control strategy or check whether the motor system is faulty.

[0086] In this embodiment, by considering the dynamic characteristics of the vehicle and the efficiency of the transmission system, the motor speed is accurately controlled, ensuring that the motor can reach the target speed as expected, achieving optimal driving effect and energy utilization.

[0087] In order to make the motor zero point calibration more accurate, the present application also proposes an implementation method for horizontally comparing the shift output torque. In another implementation, the step A202 further includes: comparing the shift output torques corresponding to the motors to obtain a set of shift deviation values ​​between the motors; selecting the maximum deviation value in the set of shift deviation values; and issuing a zero point deviation warning when the maximum deviation value reaches a preset deviation threshold.

[0088] It can be understood that the multi-motor system corresponds to multiple motors, that is, corresponds to multiple shift output torques, and multiple shift output torques are compared horizontally (that is, compared with each other), and multiple shift deviation values ​​are obtained. The set of multiple shift deviation values ​​is a shift deviation value set. For example, assume that there are two motors A and B involved in the shift process, and their shift output torques are 200 Nm and 190 Nm respectively. The shift deviation value between them is calculated to be 10 Nm, and it is assumed that this is the maximum deviation value in the current set. If the preset deviation threshold is 8 Nm, the system will consider that this deviation value exceeds the allowable range and issue a "zero deviation warning" to alert the driver or maintenance personnel.

[0089] Reference Figure 6 , Figure 6 This is a flow chart of the second embodiment of the motor zero point calibration method of the present application, based on the above Figure 2 The first embodiment shown provides a second embodiment of the motor zero point calibration method of the present application.

[0090] In the second embodiment, after step S10, the following steps are included:

[0091] Step B20, when it is detected that the gear position condition is the neutral condition, the motor speed is controlled to the current vehicle speed to obtain the neutral output torque of each motor.

[0092] It should be noted that the vehicle state corresponding to the neutral gear in this embodiment can be free sliding, the current vehicle speed can be understood as the current speed of the vehicle, usually in kilometers per hour (km / h) or miles per hour (mph), and the neutral output torque is the torque value output by the motor in the neutral condition in order to maintain the vehicle state (such as resistance compensation during free sliding) or prepare to enter the next working state.

[0093] Step B30, comparing the neutral output torques corresponding to the motors to obtain a set of neutral deviation values ​​between the motors.

[0094] It should be noted that the neutral deviation value set is a set of difference values ​​of the neutral output torques between the motors under the neutral condition.

[0095] Step B40, selecting the maximum deviation value in the neutral deviation value set.

[0096] Step B50: When the maximum deviation value reaches a preset deviation threshold, a zero point deviation warning is issued.

[0097] It should be noted that the preset deviation threshold refers to a standard value set to evaluate the consistency of the output torque between motors under neutral conditions. If the maximum deviation value exceeds this threshold, it is considered that there is a significant inconsistency in the output between the motors. The zero-point deviation warning is a warning signal issued by the system when the maximum deviation value between the motors is detected to reach or exceed the preset deviation threshold. The warning signal can be presented to the driver through the vehicle dashboard, central control display or mobile phone APP, and may be accompanied by sound or vibration prompts. For example, assume that an electric car has two drive motors A and B. Under neutral conditions, the neutral output torque of motor A is measured to be 5 Nm, and the neutral output torque of motor B is 3 Nm. The neutral deviation value between them is calculated to be 2 Nm, and it is assumed that this is the maximum deviation value in the current set. If the preset deviation threshold is 1 Nm, the system will consider that this deviation value exceeds the allowable range and issue a "zero-point deviation warning" to remind the driver or maintenance personnel to pay attention to the consistency of motor performance.

[0098] In this embodiment, by detecting the current gear condition of the vehicle, when it is detected that the gear condition is the neutral condition, the motor speed is controlled to the current vehicle speed, and the neutral output torque of each motor is obtained. The neutral output torque corresponding to each motor is compared to obtain a set of neutral deviation values ​​between the motors, and the maximum deviation value in the neutral deviation value set is selected. When the maximum deviation value reaches a preset deviation threshold, a zero point deviation warning is issued, and the detection of the zero point under the neutral condition is added to ensure that the zero point calibration can be carried out in time after the motor is installed, and an alarm is actively issued when the deviation of the motor zero point calibration result is large, so as to ensure the safety of passengers during vehicle operation and improve the driving experience.

[0099] In one implementation, based on the above embodiment, a specific implementation method of motor speed control is proposed, such as Figure 7 As shown, Figure 7The motor control system is a closed-loop control system that uses sensors to measure the actual operating status of the motor (such as current, torque, and speed), and feeds these measurements back to the controller. The controller compares these feedback signals with the desired set values ​​and calculates the required control signals to adjust the motor input (such as voltage or current) to ensure that the motor operates according to the desired instructions. For example, the command speed may be sent to the speed controller, which adjusts the motor input based on the feedback speed to change the motor's output torque and speed. Similarly, torque control and current closed-loop control are also adjusted based on their feedback signals. Vehicles with multiple motors can compare the output torque of the motor when the motor is in speed control mode (neutral or shifting), and perform motor zero-point calibration based on the correlation between the motor torque deviation and the zero-point deviation.

[0100] It should be noted that the above examples are only used to understand the present application and do not constitute a limitation on the motor zero-point calibration method of the present application. More simple transformations based on this technical concept are all within the protection scope of the present application.

[0101] This application also provides a motor zero point calibration device, please refer to Figure 8 , the motor zero point calibration device comprises:

[0102] The working condition detection module 10 is used to detect the current gear working condition of the vehicle;

[0103] The torque output module 20 is used to control each motor to enter a speed control mode when the gear position working condition is detected to be a gear shift working condition, so as to obtain the output torque corresponding to each motor;

[0104] The deviation calculation module 30 is used to determine the theoretical torque corresponding to each of the motors based on the energy balance principle, compare the output torque of each of the motors with the theoretical torque, and obtain the torque deviation value corresponding to each of the motors;

[0105] The deviation warning module 40 is used to select a maximum deviation value from the torque deviation values ​​corresponding to the motors, and issue a zero point deviation warning when the maximum deviation value reaches a preset deviation threshold.

[0106] The motor zero point calibration device provided by the present application adopts the motor zero point calibration method in the above embodiment, which can solve the technical problem of timely detecting the motor zero point deviation. Compared with the prior art, the beneficial effects of the motor zero point calibration device provided by the present application are the same as the beneficial effects of the motor zero point calibration method provided by the above embodiment, and the other technical features in the motor zero point calibration device are the same as the features disclosed in the above embodiment method, which will not be repeated here.

[0107] The present application provides a motor zero-point calibration device, which includes: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the motor zero-point calibration method in the above-mentioned embodiment one.

[0108] Reference below Fig. 9 , which shows a schematic diagram of the structure of a motor zero-point calibration device suitable for implementing the embodiment of the present application. The motor zero-point calibration device in the embodiment of the present application may include but is not limited to mobile terminals such as mobile phones, laptop computers, digital broadcast receivers, PDAs (Personal Digital Assistants), PADs (Portable Application Descriptions), PMPs (Portable Media Players), vehicle-mounted terminals (such as vehicle-mounted navigation terminals), etc., and fixed terminals such as digital TVs, desktop computers, etc. Fig. 9 The motor zero-point calibration device shown is merely an example and should not bring any limitation to the functions and scope of use of the embodiments of the present application.

[0109] like Fig. 9 As shown, the motor zero point calibration device may include a processing device 1001 (such as a central processing unit, a graphics processor, etc.), which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM: Read Only Memory) 1002 or a program loaded from a storage device 1003 to a random access memory (RAM: Random Access Memory) 1004. In RAM1004, various programs and data required for the operation of the motor zero point calibration device are also stored. The processing device 1001, ROM1002 and RAM1004 are connected to each other through a bus 1005. An input / output (I / O) interface 1006 is also connected to the bus. Generally, the following systems can be connected to the I / O interface 1006: an input device 1007 including, for example, a touch screen, a touch pad, a keyboard, a mouse, an image sensor, a microphone, an accelerometer, a gyroscope, etc.; an output device 1008 including, for example, a liquid crystal display (LCD: Liquid Crystal Display), a speaker, a vibrator, etc.; a storage device 1003 including, for example, a magnetic tape, a hard disk, etc.; and a communication device 1009. The communication device 1009 can allow the motor zero point calibration device to communicate with other devices wirelessly or by wire to exchange data. Fig. 9The motor zero point calibration device with various systems is shown in the figure, but it should be understood that it is not required to implement or have all the systems shown. More or fewer systems can be implemented or have instead.

[0110] In particular, according to the embodiments disclosed in the present application, the process described above with reference to the flowchart can be implemented as a computer software program. For example, the embodiments disclosed in the present application include a computer program product, which includes a computer program carried on a computer-readable medium, and the computer program includes a program code for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from a network through a communication device, or installed from a storage device 1003, or installed from a ROM 1002. When the computer program is executed by the processing device 1001, the above-mentioned functions defined in the method of the embodiment disclosed in the present application are executed.

[0111] The motor zero point calibration device provided by the present application adopts the motor zero point calibration method in the above embodiment, which can solve the technical problem of timely detecting the motor zero point deviation. Compared with the prior art, the beneficial effects of the motor zero point calibration device provided by the present application are the same as the beneficial effects of the motor zero point calibration method provided by the above embodiment, and the other technical features in the motor zero point calibration device are the same as the features disclosed in the method of the previous embodiment, which will not be repeated here.

[0112] It should be understood that the various parts disclosed in this application can be implemented by hardware, software, firmware or a combination thereof. In the description of the above embodiments, specific features, structures, materials or characteristics can be combined in any one or more embodiments or examples in a suitable manner.

[0113] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

[0114] The present application provides a computer-readable storage medium having computer-readable program instructions (ie, computer programs) stored thereon, and the computer-readable program instructions are used to execute the motor zero-point calibration method in the above-mentioned embodiment.

[0115] The computer-readable storage medium provided in the present application may be, for example, a USB flash drive, but is not limited to electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, systems or devices, or any combination of the above. More specific examples of computer-readable storage media may include, but are not limited to: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM: Random Access Memory), a read-only memory (ROM: Read Only Memory), an erasable programmable read-only memory (EPROM: Erasable Programmable Read Only Memory or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM: CD-Read Only Memory), an optical storage device, a magnetic storage device, or any suitable combination of the above. In this embodiment, the computer-readable storage medium may be any tangible medium containing or storing a program, which may be used by or in combination with an instruction execution system, system or device. The program code contained on the computer-readable storage medium may be transmitted using any appropriate medium, including but not limited to: wires, optical cables, RF (Radio Frequency: Radio Frequency), etc., or any suitable combination of the above.

[0116] The computer-readable storage medium may be included in the motor zero-point calibration device; or may exist independently without being assembled into the motor zero-point calibration device.

[0117] The above-mentioned computer-readable storage medium carries one or more programs. When the above-mentioned one or more programs are executed by the motor zero-point calibration device, the motor zero-point calibration device: detects the current gear condition of the vehicle; when it is detected that the gear condition is a gear shifting condition, controls each motor to enter a speed control mode to obtain the output torque corresponding to each motor; determines the theoretical torque corresponding to each motor based on the energy balance principle, compares the output torque of each motor with the theoretical torque, and obtains the torque deviation value corresponding to each motor; selects the maximum deviation value from the torque deviation values ​​corresponding to each motor, and when the maximum deviation value reaches a preset deviation threshold, issues a zero-point deviation warning.

[0118] Computer program code for performing the operations of the present application may be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages ​​such as Java, Smalltalk, C++, and conventional procedural programming languages ​​such as "C" or similar programming languages. The program code may be executed entirely on the user's computer, partially on the user's computer, as a separate software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the case of a remote computer, the remote computer may be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0119] The flow chart and block diagram in the accompanying drawings illustrate the possible architecture, function and operation of the system, method and computer program product according to various embodiments of the present application. In this regard, each square box in the flow chart or block diagram can represent a module, a program segment or a part of a code, and the module, the program segment or a part of the code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the square box can also occur in a sequence different from that marked in the accompanying drawings. For example, two square boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each square box in the block diagram and / or flow chart, and the combination of the square boxes in the block diagram and / or flow chart can be implemented with a dedicated hardware-based system that performs a specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions.

[0120] The modules involved in the embodiments described in this application may be implemented by software or hardware, wherein the name of the module does not constitute a limitation on the unit itself in some cases.

[0121] The readable storage medium provided in the present application is a computer-readable storage medium, which stores computer-readable program instructions (i.e., computer programs) for executing the above-mentioned motor zero-point calibration method, and can solve the technical problem of timely detecting the motor zero-point deviation. Compared with the prior art, the beneficial effects of the computer-readable storage medium provided in the present application are the same as the beneficial effects of the motor zero-point calibration method provided in the above-mentioned embodiment, and will not be elaborated here.

[0122] The present application also provides a computer program product, including a computer program, which implements the steps of the motor zero point calibration method as described above when executed by a processor.

[0123] The computer program product provided by the present application can solve the technical problem of timely detecting the zero point deviation of the motor. Compared with the prior art, the beneficial effects of the computer program product provided by the present application are the same as the beneficial effects of the motor zero point calibration method provided by the above embodiment, which will not be repeated here.

[0124] The above descriptions are only some embodiments of the present application, and are not intended to limit the patent scope of the present application. All equivalent structural changes made using the contents of the present application specification and drawings under the technical concept of the present application, or direct / indirect applications in other related technical fields are included in the patent protection scope of the present application.

Claims

1. A motor zero point calibration method, characterized in that: The method includes: Detect the current gear position of the vehicle; When it is detected that the gear position working condition is a gear shift working condition, each motor is controlled to enter a speed control mode to obtain an output torque corresponding to each motor; Determine the theoretical torque corresponding to each of the motors based on the energy balance principle, compare the output torque of each of the motors with the theoretical torque, and obtain a torque deviation value corresponding to each of the motors; Selecting a maximum deviation value from the torque deviation values ​​corresponding to the motors, and issuing a zero deviation warning when the maximum deviation value reaches a preset deviation threshold; Wherein, when it is detected that the gear position working condition is a gear shift working condition, the step of controlling each motor to enter a speed control mode and obtaining the output torque corresponding to each motor includes: When it is detected that the vehicle operating condition changes from neutral to a target gear, the target motor speed is calculated according to the target vehicle speed corresponding to the target gear; The motor speed is controlled to the target motor speed to obtain the gear shift output torque corresponding to each motor, and the gear shift output torque is the torque value corresponding to the output when the vehicle gear is switched to the target gear.

2. The method according to claim 1, characterized in that The step of determining the theoretical torque corresponding to each of the motors based on the energy balance principle, comparing the output torque of each of the motors with the theoretical torque, and obtaining the torque deviation value corresponding to each of the motors comprises: Calculating a theoretical torque according to the target motor speed, the current vehicle speed and the rotational inertia of the corresponding motor; The output torque of each of the motors is compared with the theoretical torque to obtain a torque deviation value corresponding to each of the motors.

3. The method according to claim 1, characterized in that After the step of controlling the motor speed to the target motor speed to obtain the shift output torque corresponding to each motor, the method further includes: Comparing the shift output torques corresponding to the motors to obtain a set of shift deviation values ​​between the motors; Selecting the maximum deviation value in the gear shift deviation value set; When the maximum deviation value reaches a preset deviation threshold, a zero point deviation warning is issued.

4. The method as claimed in claim 2, characterized in that The step of calculating the theoretical torque according to the target motor speed, the current vehicle speed and the rotational inertia of the corresponding motor, the theoretical torque calculation formula is expressed as: In the above formula, represents the theoretical torque, Indicates the inertia coefficient of the corresponding motor, Indicates the moment of inertia of the corresponding motor, represents pi, Indicates the shift time interval, The speed change is the difference between the target motor speed and the current vehicle speed.

5. The method according to claim 1, characterized in that After the step of detecting the current gear position of the vehicle, the method further comprises: When the gear position is detected to be in neutral, the motor speed is controlled to the current vehicle speed to obtain the neutral output torque of each motor; Comparing the neutral output torques corresponding to the motors to obtain a set of neutral deviation values ​​between the motors; Selecting the maximum deviation value in the neutral deviation value set; When the maximum deviation value reaches a preset deviation threshold, a zero point deviation warning is issued.

6. A motor zero point calibration device, characterized in that: The device comprises: A working condition detection module, used to detect the current gear working condition of the vehicle; The torque output module is used to control each motor to enter a speed control mode when the gear position working condition is detected to be a gear shift working condition, so as to obtain the output torque corresponding to each motor; a deviation calculation module, used to determine the theoretical torque corresponding to each of the motors based on the energy balance principle, compare the output torque of each of the motors with the theoretical torque, and obtain a torque deviation value corresponding to each of the motors; A deviation warning module, used for selecting a maximum deviation value from the torque deviation values ​​corresponding to the motors, and issuing a zero deviation warning when the maximum deviation value reaches a preset deviation threshold; The torque output module is also used to calculate the target motor speed according to the target vehicle speed corresponding to the target gear when it is detected that the vehicle operating condition changes from neutral to the target gear; control the motor speed to the target motor speed to obtain the gear shift output torque corresponding to each motor, and the gear shift output torque is the torque value corresponding to the output when the vehicle gear is converted to the target gear.

7. A motor zero point calibration device, characterized in that: The device comprises: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the computer program is configured to implement the steps of the motor zero-point calibration method according to any one of claims 1 to 5.

8. A storage medium, characterized in that: The storage medium is a computer-readable storage medium, and a computer program is stored on the storage medium. When the computer program is executed by a processor, the steps of the motor zero point calibration method according to any one of claims 1 to 5 are implemented.

9. A computer program product, characterized in that The computer program product comprises a computer program, and when the computer program is executed by a processor, the steps of the motor zero point calibration method according to any one of claims 1 to 5 are implemented.

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