Disclosure of Invention
Based on the method, the device, the medium and the vehicle for controlling the torque based on the torque distribution ratio adjustment are provided, and the phenomenon that the response of the vehicle to the Tip-in operation is not enough in time in the prior art is improved.
In a first aspect, there is provided a torque control method based on torque split ratio adjustment, the method comprising:
when receiving a rapid accelerator pedal operation initiated by a driver, acquiring a target torque, an original distribution ratio, an original front motor torque and an original rear motor torque of the whole vehicle;
Judging whether the front motor is in a torque zero crossing state according to the front motor original torque and the front motor request torque;
If the front motor is in a torque zero crossing state and the rear motor is not in a torque zero crossing state, the original distribution ratio is adjusted to obtain a first target distribution ratio through the original torque of the front motor, the request torque of the front motor and the target torque of the whole vehicle;
and if the rear motor is in a torque zero crossing state and the front motor is not in a torque zero crossing state, adjusting the original distribution ratio to obtain a second target distribution ratio through the original torque of the rear motor, the request torque of the rear motor and the target torque of the whole vehicle, and distributing the target torque of the whole vehicle according to the second target distribution ratio to obtain a target torque of the second front motor and a target torque of the second rear motor so as to reduce the torque distribution of the rear motor and increase the torque distribution of the front motor.
With reference to the first aspect, in a first possible implementation manner of the first aspect, the step of adjusting the original distribution ratio to obtain a first target distribution ratio through the original torque of the front motor, the requested torque of the front motor, and the target torque of the whole vehicle includes:
obtaining a front motor unsolicited torque according to the difference between the front motor original torque and the front motor solicited torque;
Calculating a first torque distribution ratio according to the original torque of the front motor, the unsolicited torque of the front motor, the target torque of the whole vehicle and a preset front axle transmission ratio;
and comparing the first torque distribution ratio with the original distribution ratio, and taking the largest one of the first torque distribution ratio and the original distribution ratio as a first target distribution ratio.
With reference to the first possible implementation manner of the first aspect, in a second possible implementation manner of the first aspect, before the step of adjusting the original distribution ratio to obtain the first target distribution ratio by the front motor original torque, the front motor request torque, and the vehicle target torque, the method further includes:
Acquiring a preset first torque threshold value, and comparing the unsolicited torque of the front motor with the first torque threshold value;
And if the unsolicited torque of the front motor is larger than the first torque threshold and the target torque of the whole vehicle is larger than zero, executing the step of adjusting the original distribution ratio to obtain a first target distribution ratio through the original torque of the front motor, the solicited torque of the front motor and the target torque of the whole vehicle.
With reference to the first aspect, in a third possible implementation manner of the first aspect, the step of adjusting the original distribution ratio to obtain the second target distribution ratio through the original torque of the rear motor, the requested torque of the rear motor, and the target torque of the whole vehicle includes:
obtaining a rear motor unsolicited torque according to the difference between the rear motor original torque and the rear motor solicited torque;
Calculating a second torque distribution ratio according to the original torque of the rear motor, the unsolicited torque of the rear motor, the target torque of the whole vehicle and a preset rear axle transmission ratio;
And comparing the second torque distribution ratio with the original distribution ratio, and taking the smallest one of the second torque distribution ratio and the original distribution ratio as a second target distribution ratio.
With reference to the third possible implementation manner of the first aspect, in a fourth possible implementation manner of the first aspect, before the step of adjusting the original distribution ratio to obtain the second target distribution ratio by the rear motor original torque, the rear motor request torque, and the target torque of the whole vehicle, the method further includes:
Acquiring a preset second torque threshold value, and comparing the unsolicited torque of the rear motor with the second torque threshold value;
And if the unsolicited torque of the rear motor is larger than the second torque threshold and the target torque of the whole vehicle is larger than zero, executing the step of adjusting the original distribution ratio to obtain a second target distribution ratio through the original torque of the rear motor, the requested torque of the rear motor and the target torque of the whole vehicle.
With reference to the first aspect, in a fifth implementation manner of the first aspect, the step of determining whether the front motor is in a torque zero crossing state according to the front motor original torque and the front motor requested torque includes:
acquiring a preset third torque threshold value and a preset fourth torque threshold value, and judging whether the original torque of the front motor is larger than the third torque threshold value and whether the requested torque of the front motor is larger than the fourth torque threshold value;
If yes, setting the set value of the front motor as a preset first value; if not, setting the set numerical value of the front motor as a preset second numerical value;
collecting the current speed of a vehicle, and obtaining the unsolicited torque of the front motor according to the difference between the original torque of the front motor and the solicited torque of the front motor;
Acquiring a preset fifth torque threshold value, a preset sixth torque threshold value and a preset vehicle speed threshold value, and judging whether the original torque of the front motor is smaller than the third torque threshold value, whether the requested torque of the front motor is larger than the fifth torque threshold value, whether the unsolicited torque of the front motor is smaller than the sixth torque threshold value and whether the current vehicle speed is smaller than the vehicle speed threshold value;
If yes, setting the reset value of the front motor as the first value; if not, setting the reset value of the front motor as the second value;
when the value set by the front motor is the first value and the value reset by the front motor is the second value, or the value set by the front motor jumps from the first value to the second value and the value reset by the front motor is the second value, judging that the front motor is in a torque zero crossing state;
And when the set value of the front motor is the second value and the reset value of the front motor is the first value, or the set value of the front motor is the second value and the reset value of the front motor is changed from the first value to the second value, judging that the front motor is not in a torque zero crossing state.
With reference to the fifth possible implementation manner of the first aspect, in a sixth possible implementation manner of the first aspect, the step of determining whether the rear motor is in a torque zero crossing state according to the rear motor original torque and the rear motor requested torque includes:
judging whether the original torque of the rear motor is larger than the third torque threshold value and whether the requested torque of the rear motor is larger than the fourth torque threshold value;
if yes, setting the set value of the rear motor as the first value; if not, setting the set numerical value of the rear motor as the second numerical value;
obtaining a rear motor unsolicited torque according to the difference between the rear motor original torque and the rear motor solicited torque;
Judging whether the original torque of the rear motor is smaller than the third torque threshold, whether the requested torque of the rear motor is larger than the fifth torque threshold, whether the unsolicited torque of the rear motor is smaller than the sixth torque threshold and whether the current vehicle speed is smaller than the vehicle speed threshold;
If yes, setting the reset value of the rear motor as the first value; if not, setting the reset value of the rear motor as the second value;
when the set value of the rear motor is the first value and the reset value of the rear motor is the second value, or the set value of the rear motor jumps from the first value to the second value and the reset value of the rear motor is the second value, judging that the rear motor is in a torque zero crossing state;
and when the set value of the rear motor is the second value and the reset value of the rear motor is the first value, or the set value of the rear motor is the second value and the reset value of the rear motor is changed from the first value to the second value, judging that the rear motor is not in a torque zero crossing state.
In a second aspect, there is provided a torque control apparatus based on torque split ratio adjustment, the apparatus comprising:
The parameter acquisition unit is used for acquiring the target torque, the original distribution ratio, the original front motor torque and the original rear motor torque of the whole vehicle when receiving the rapid accelerator stepping operation initiated by a driver;
The torque zero-crossing state judging unit is used for judging whether the front motor is in a torque zero-crossing state according to the original torque of the front motor and the requested torque of the front motor;
The first adjusting unit is used for adjusting the original distribution ratio to obtain a first target distribution ratio through the original torque of the front motor, the request torque of the front motor and the target torque of the whole vehicle if the front motor is in a torque zero crossing state and the rear motor is not in a torque zero crossing state;
and the second adjusting unit is used for adjusting the original distribution ratio to obtain a second target distribution ratio through the original torque of the rear motor, the requested torque of the rear motor and the target torque of the whole vehicle if the rear motor is in the torque zero crossing state and the front motor is not in the torque zero crossing state, distributing the target torque of the whole vehicle according to the second target distribution ratio to obtain a target torque of the second front motor and a target torque of the second rear motor so as to reduce the torque distribution of the rear motor and increase the torque distribution of the front motor.
In a third aspect, a computer readable storage medium is provided, on which a computer program is stored which, when being executed by a processor, implements the steps of the torque control method based on torque split ratio adjustment as described in the first aspect or in connection with any one of the possible embodiments of the first aspect.
In a fourth aspect, there is provided a vehicle comprising the torque control device based on torque split ratio adjustment of the second aspect, wherein the torque control device based on torque split ratio adjustment is adapted to perform the steps of the torque control method based on torque split ratio adjustment as described in the first aspect or in connection with any one of the possible embodiments of the first aspect.
The torque control method, the device, the medium and the vehicle based on the torque distribution ratio adjustment acquire the whole vehicle target torque, the original distribution ratio, the original front motor torque and the original rear motor torque when the rapid accelerator stepping operation initiated by a driver is received, perform gradient and filtering processing on the original front motor torque and the original rear motor torque to obtain corresponding front motor request torque and rear motor request torque, judge whether the front motor is in a torque zero crossing state according to the original front motor torque and the front motor request torque, judge whether the rear motor is in a torque zero crossing state according to the original rear motor torque and the request rear motor torque, adjust the original distribution ratio to obtain a first target ratio through the original front motor torque, the original front motor request torque and the target rear motor torque when the front motor is in the torque zero crossing state and the rear motor is not in the torque zero crossing state, distribute the whole vehicle target torque according to the first target distribution ratio, increase the torque distribution of the first front motor target torque and the first rear motor target torque to reduce the torque distribution of the front motor, judge whether the front motor is in the torque zero crossing state according to the corresponding front motor and the rear motor request torque, and the first rear motor target torque is in the first zero crossing state when the corresponding front motor distribution torque and the rear motor is not in the torque zero crossing state, adjust the first target ratio is achieved through the original front motor distribution torque and the first target torque distribution ratio and the whole vehicle target torque is increased, and the second target ratio is obtained when the corresponding to the first target distribution torque is in the zero crossing state and the first target distribution ratio is not in the whole vehicle, the second front motor target torque and the second rear motor target torque are the torques which the front motor and the rear motor need to reach corresponding to the rapid accelerator stepping operation. Therefore, by means of the torque control method based on the torque distribution ratio adjustment, the torque zero crossing sections of the front motor and the rear motor can be identified, so that when only one of the front motor and the rear motor is in the torque zero crossing state, the torque distribution of the motor in the torque zero crossing state is reduced from the source by means of adjusting the torque distribution ratio at the front section of the torque link, the torque distribution of the motor in the torque zero crossing state is partially overlapped to the motor not in the torque zero crossing state, and the response of the vehicle to Tip-in operation in the torque zero crossing stage is further improved. Compared with the prior art, the method has the beneficial effects that the phenomenon that the response of the vehicle to the Tip-in operation is not enough in time in the torque zero crossing stage is improved, the response of the vehicle accords with the expectation of a driver, and the drivability of the vehicle and the driving experience of the driver are improved.
Detailed Description
The present application will be described in further detail with reference to the drawings and examples, in order to make the objects, technical solutions and advantages of the present application more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the application.
It should be noted that, the illustrations provided in the present embodiment merely illustrate the basic concept of the present application by way of illustration, and only the components related to the present application are shown in the drawings and are not drawn according to the number, shape and size of the components in actual implementation, and the form, number and proportion of the components in actual implementation may be arbitrarily changed, and the layout of the components may be more complex.
The structures, proportions, sizes, etc. shown in the drawings herein are shown in detail for purposes of illustration only, and are not intended to limit the scope of the application, which is defined in the claims, any structural modification, proportional change or size adjustment should still fall within the scope of the disclosure without affecting the efficacy and achievement of the present application.
References in this specification to orientations or positional relationships as "upper", "lower", "left", "right", "intermediate", "longitudinal", "transverse", "horizontal", "inner", "outer", "radial", "circumferential", etc., are based on the orientation or positional relationships shown in the drawings, are also for convenience of description only, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore are not to be construed as limiting the application. Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
In one embodiment, as shown in fig. 1, there is provided a torque control method based on torque distribution ratio adjustment, comprising the steps of:
and S1, when receiving a rapid accelerator stepping operation initiated by a driver, acquiring a target torque, an original distribution ratio, an original front motor torque and an original rear motor torque of the whole vehicle, and carrying out gradient and filtering processing on the original front motor torque and the original rear motor torque to obtain a corresponding front motor request torque and a corresponding rear motor request torque.
In a specific embodiment, when a rapid accelerator pedal (Tip-in) operation initiated by a driver is received, a corresponding accelerator pedal depth can be obtained according to the rapid accelerator pedal operation, a preset mapping table between the accelerator pedal depth and a target torque of the whole vehicle is obtained, and a table look-up operation is performed in the mapping table through the accelerator pedal depth to obtain the target torque of the whole vehicle corresponding to the accelerator pedal depth. The target torque of the whole vehicle can be torque which is subjected to driving gradient filtering and capacity limiting processing.
The original distribution ratio can be determined by combining a stability distribution principle and an efficiency optimal distribution principle, so that the best economical efficiency of the vehicle is realized on the premise of stable running, and the value range is [0,1]. By way of example, the stability distribution principle means that the front and rear axle torque needs to be specifically distributed according to the real-time axle load distribution, and cannot exceed the maximum value allowed by the road surface adhesion, so as to avoid the vehicle from entering a unstable state. The efficiency optimal allocation principle is that the efficiency comprises motor efficiency and transmission efficiency, and the most main factors are motor efficiency, so that the efficiency optimal allocation principle taking the motor efficiency as a consideration is mainly that the working point of a motor is moved to a place with higher efficiency, namely, under a certain fixed rotating speed, whether the single motor driving efficiency or the double motor driving efficiency is higher is judged according to the required size, and if the double motor driving efficiency is higher, the torque allocation ratio is calculated according to the front motor efficiency MAP and the rear motor efficiency MAP and the transmission ratio.
After the target torque and the original distribution ratio of the whole vehicle are obtained, the target torque of the whole vehicle is distributed through the original distribution ratio, a preset front axle transmission ratio and a preset rear axle distribution ratio to obtain the original torque of the front motor and the original torque of the rear motor, wherein the original torque of the front motor and the original torque of the rear motor are the torques which are required to be achieved by the front motor and the rear motor in response to the rapid accelerator stepping operation respectively, and mathematical expressions which can be adopted in the steps comprise:
TReq_F_Raw＝TReq_All*(1-Kb)/if
TReq_R_Raw＝TReq_All*Kb/ir
Wherein, TReq_F_Raw is the original torque of the front motor, TReq_All is the target torque of the whole vehicle, Kb is the original distribution ratio, if is the front axle transmission ratio, TReq_R_Raw is the original torque of the rear motor, and ir is the rear axle transmission ratio.
The original torque of the front motor and the original torque of the rear motor are theoretical values which are calculated based on Tip-in operation and are needed to be achieved by the front motor and the rear motor, the front motor request torque is a theoretical value obtained by carrying out gradient and filtering processing on the original torque of the front motor, and the rear motor request torque is a theoretical value obtained by carrying out gradient and filtering processing on the original torque of the rear motor. Therefore, the front motor request torque may not coincide with the front motor original torque, but the front motor request torque does not exceed the front motor original torque, that is, there is a case where the front motor request torque is less than or equal to the front motor original torque, and similarly, the rear motor request torque may not coincide with the rear motor original torque, and there is a case where the rear motor request torque is less than or equal to the rear motor original torque.
Therefore, the torque zero crossing condition of the front motor and the rear motor can be monitored through subsequent steps, the torque distribution of the motor in the torque zero crossing state is reduced from the source through a mode of adjusting the torque distribution ratio, the torque distribution is overlapped to the motor in the torque zero crossing state, the response of the vehicle to the Tip-in operation in the torque zero crossing stage is further improved, and the driving experience of a driver is improved.
In order to improve the NVH problem caused by the sudden rise of the torques of the front motor and the rear motor, the gradient processing can refer to gradient slowing processing near a torque zero crossing point of the original torque of the front motor and the original torque of the rear motor, and the filtering processing can refer to drivability filtering, namely, smooth torque transition between adjacent moments is realized, so that the change of the acceleration of the vehicle is smoother, and the impact feeling of the sudden acceleration of the vehicle to a user is reduced.
S2, judging whether the front motor is in a torque zero crossing state according to the front motor original torque and the front motor request torque, and judging whether the rear motor is in the torque zero crossing state according to the rear motor original torque and the rear motor request torque.
In a specific embodiment, the step of judging whether the front motor is in a torque zero-crossing state according to the front motor original torque and the front motor request torque comprises the steps of acquiring a preset third torque threshold value and a preset fourth torque threshold value, judging whether the front motor original torque is larger than the third torque threshold value and whether the front motor request torque is larger than the fourth torque threshold value, if so, setting a value set by the front motor to a preset first value, if not, setting the value set by the front motor to a preset second value, acquiring a current vehicle speed, acquiring a preset fifth torque threshold value, a preset sixth torque threshold value and a vehicle speed threshold value, judging whether the front motor original torque is smaller than the third torque threshold value, whether the front motor request torque is larger than the fifth torque threshold value, whether the front motor non-request torque is smaller than the sixth torque threshold value and whether the current vehicle speed is smaller than the vehicle speed threshold value, if not, resetting the value set by the front motor is the first value, resetting the value set by the front motor to the first value, resetting the value set by the front motor is the second value, and resetting the value set by the front motor is the first value, and resetting the value set by the first value is the value set by the front motor non-zero-crossing state, and resetting value is the value set by the first value and resetting value is the value set by the value. Or when the set value of the front motor is the second value and the reset value of the front motor jumps from the first value to the second value, judging that the front motor is not in a torque zero crossing state.
For example, the first value may be 1, the second value may be 0, the third and fourth torque thresholds may be obtained by a real vehicle test calibration and may range from (-30, 0) to a value greater than the fourth torque threshold, the fifth, sixth and vehicle speed thresholds may also be obtained by a real vehicle test calibration, the fifth torque threshold may be generally set to a value greater than 20, the sixth torque threshold may be generally set to a value greater than 5, and the vehicle speed threshold may be generally set to a value greater than 5 kph.
Taking the first value as 1 and the second value as 0 as an example for explanation, after the values of the front motor setting and the front motor resetting are determined, the values of the front motor zero crossing flag bit can be obtained according to the values of the front motor setting and the front motor resetting, wherein the front motor zero crossing flag bit is used for indicating whether the front motor is in a torque zero crossing state or not. Specifically, reference may be made to a value table of zero crossing flag bits of the front motor as shown in table 1.
Table 1 front motor zero crossing flag bit value table
| Sequence number | SF | RF | ZF |
| 1 | 1 | 0 | 1 |
| 2 | 0 | 1 | 0 |
| 3 (SF jump from 1 to 0) | 0 | 0 | 1 (Result of holding sequence number 1) |
| 4 (RF from 1 to 0) | 0 | 0 | 0 (Result of holding sequence number 2) |
In Table 1, SF indicates that the front motor is set, RF indicates that the front motor is reset, ZF indicates that the front motor is zero crossing flag bit, when the value of ZF is 1, the front motor is in a torque zero crossing state, and when the value of ZF is 0, the front motor is not in a torque zero crossing state.
The step of judging whether the rear motor is in the torque zero crossing state according to the rear motor original torque and the rear motor request torque includes judging whether the rear motor original torque is greater than the third torque threshold and whether the rear motor request torque is greater than the fourth torque threshold; if so, setting the value set by the rear motor to the first value, if not, setting the value set by the rear motor to the second value, obtaining the rear motor unsolicited torque according to the difference between the rear motor original torque and the rear motor solicited torque, judging whether the rear motor original torque is smaller than the third torque threshold, whether the rear motor solicited torque is larger than the fifth torque threshold, whether the rear motor unsolicited torque is smaller than the sixth torque threshold and whether the current vehicle speed is smaller than the vehicle speed threshold, if so, setting the value reset by the rear motor to the first value, if not, setting the value reset by the rear motor to the second value, when the value set by the rear motor is the first value and the value reset by the rear motor is the second value, or when the value set by the rear motor jumps from the first value to the second value and the value reset by the rear motor is the second value, judging that the rear motor is in the zero crossing state is the second value, and judging that the rear motor is not in a torque zero crossing state.
Similarly, the first value is 1, the second value is 0, and after the values of the rear motor setting and the rear motor resetting are determined, the value of the rear motor zero crossing flag bit can be obtained according to the values of the rear motor setting and the rear motor resetting, wherein the rear motor zero crossing flag bit is used for indicating whether the rear motor is in a torque zero crossing state. Specifically, the value table of the zero crossing zone bit of the rear motor can be seen as shown in the table 2.
Table 2 rear motor zero crossing flag bit value table
In Table 2, SR indicates that the front motor is set, ZR indicates that the front motor is reset, ZR indicates that the front motor is zero crossing flag bit, when the value of ZR is 1, it indicates that the front motor is in a torque zero crossing state, and when the value of ZR is 0, it indicates that the front motor is not in a torque zero crossing state.
And S31, if the front motor is in a torque zero crossing state and the rear motor is not in a torque zero crossing state, adjusting the original distribution ratio to obtain a first target distribution ratio through the original torque of the front motor, the request torque of the front motor and the target torque of the whole vehicle, and distributing the target torque of the whole vehicle according to the first target distribution ratio to obtain a target torque of the first front motor and a target torque of the first rear motor so as to reduce the torque distribution of the front motor and increase the torque distribution of the rear motor.
In a specific embodiment, the step of adjusting the original distribution ratio to obtain a first target distribution ratio through the original front motor torque, the front motor request torque and the target whole vehicle torque comprises the steps of obtaining a front motor unsolicited torque according to the difference between the front motor original torque and the front motor request torque, and calculating the first torque distribution ratio according to the front motor original torque, the front motor unsolicited torque, the target whole vehicle torque and a preset front axle transmission ratio, wherein the adopted mathematical expression comprises the following steps:
KF is the first torque split ratio,And comparing the first torque distribution ratio with the original distribution ratio, and taking the largest one of the first torque distribution ratio and the original distribution ratio as a first target distribution ratio.
In a preferred embodiment, in order to more precisely perform the operation of adjusting the original distribution ratio, before the step of obtaining the first target distribution ratio by adjusting the original distribution ratio by the original torque of the front motor, the requested torque of the front motor and the target torque of the whole vehicle, the method further includes obtaining a preset first torque threshold value, comparing the unsolicited torque of the front motor with the first torque threshold value, if the unsolicited torque of the front motor is greater than the first torque threshold value and the target torque of the whole vehicle is greater than zero, performing the step of obtaining the first target distribution ratio by adjusting the original torque of the front motor, the requested torque of the front motor and the target torque of the whole vehicle, and if not, not performing the step of obtaining the first target distribution ratio by adjusting the original distribution ratio, and operating the front motor and the rear motor according to the requested torque of the front motor and the requested torque of the rear motor, respectively. The first torque threshold may be determined by a real vehicle test calibration, and illustratively the first torque threshold is typically set to a value greater than 10.
Further, after the first target distribution ratio is obtained, in order to further improve the NVH problem, gradient processing may be performed on the first target distribution ratio. The gradient value corresponding to the gradient treatment can be set according to the first target distribution ratio after the gradient treatment obtained in the previous period and the first target distribution ratio obtained in the current period, wherein the setting principle is that the larger the difference value between the first target distribution ratio after the gradient treatment obtained in the previous period and the first target distribution ratio obtained in the current period is, the larger the gradient value used for the gradient treatment in the current period is, the gradient treatment in the current period is gradient ascending if the first target distribution ratio after the gradient treatment obtained in the previous period is larger than the first target distribution ratio obtained in the current period, and the gradient treatment in the current period is gradient descending if the first target distribution ratio after the gradient treatment obtained in the previous period is smaller than the first target distribution ratio obtained in the current period Yu Benzhou.
After the first target distribution ratio or the first target distribution ratio after gradient processing is obtained, distributing the whole vehicle target torque according to the first target distribution ratio or the first target distribution ratio after gradient processing to obtain a first front motor target torque for controlling the front motor to run and a first rear motor target torque for controlling the rear motor to run, and then controlling the front motor and the rear motor to run respectively.
And S32, if the rear motor is in a torque zero crossing state and the front motor is not in a torque zero crossing state, adjusting the original distribution ratio to obtain a second target distribution ratio through the original torque of the rear motor, the request torque of the rear motor and the target torque of the whole vehicle, and distributing the target torque of the whole vehicle according to the second target distribution ratio to obtain a target torque of the second front motor and a target torque of the second rear motor so as to reduce the torque distribution of the rear motor and increase the torque distribution of the front motor.
The step of adjusting the original distribution ratio to obtain a second target distribution ratio through the original rear motor torque, the rear motor request torque and the whole vehicle target torque is similar to the step of calculating the first target distribution ratio, and comprises the steps of obtaining rear motor unsolicited torque according to the difference between the rear motor original torque and the rear motor request torque, and calculating the second torque distribution ratio according to the rear motor original torque, the rear motor unsolicited torque, the whole vehicle target torque and a preset rear axle transmission ratio, wherein the adopted mathematical expression comprises the following steps:
KR is the second torque split ratio,And comparing the second torque distribution ratio with the original distribution ratio, and taking the smallest one of the second torque distribution ratio and the original distribution ratio as a second target distribution ratio.
In a preferred embodiment, in order to more precisely perform the operation of adjusting the original distribution ratio, before the step of adjusting the original distribution ratio to obtain the second target distribution ratio by the original torque of the rear motor, the requested torque of the rear motor and the target torque of the whole vehicle, the method further includes obtaining a preset second torque threshold value, comparing the unsolicited torque of the rear motor with the second torque threshold value, if the unsolicited torque of the rear motor is greater than the second torque threshold value and the target torque of the whole vehicle is greater than zero, performing the step of adjusting the original distribution ratio to obtain the second target distribution ratio by the original torque of the rear motor, the requested torque of the rear motor and the target torque of the whole vehicle, and if not, not performing the step of adjusting the original distribution ratio to obtain the second target distribution ratio, and operating the front motor and the rear motor according to the requested torque of the front motor and the requested torque of the rear motor, respectively. The second torque threshold may be determined by a real vehicle test calibration, and illustratively the second torque threshold is typically set to a value greater than 10.
Further, after the second target distribution ratio is obtained, in order to further improve the NVH problem, gradient processing may be performed on the second target distribution ratio. The gradient value corresponding to the gradient treatment can be set according to the second target distribution ratio after the gradient treatment obtained in the previous period and the second target distribution ratio obtained in the current period, wherein the setting principle is that the larger the difference value between the second target distribution ratio after the gradient treatment obtained in the previous period and the second target distribution ratio obtained in the current period is, the larger the gradient value used for the gradient treatment in the current period is, the gradient treatment in the current period is gradient ascending if the second target distribution ratio after the gradient treatment obtained in the previous period is larger than the second target distribution ratio obtained in the current period, and the gradient treatment in the current period is gradient descending if the second target distribution ratio after the gradient treatment obtained in the previous period is smaller than the second target distribution ratio obtained in the current period Yu Benzhou.
After the second target distribution ratio or the second target distribution ratio after gradient processing is obtained, distributing the whole vehicle target torque according to the second target distribution ratio or the second target distribution ratio after gradient processing to obtain a second front motor target torque for controlling the front motor to run and a second rear motor target torque for controlling the rear motor to run, and then controlling the front motor and the rear motor to run respectively.
The mathematical expression adopted in the step of obtaining the second front motor target torque and the second rear motor target torque by distributing the whole vehicle target torque according to the first target distribution ratio is the same as the mathematical expression adopted in the step of obtaining the front motor original torque and the rear motor original torque by distributing the whole vehicle target torque according to the original distribution ratio, and is not repeated here.
In summary, by identifying the torque zero-crossing sections of the front motor and the rear motor, when only one of the front motor and the rear motor is in the torque zero-crossing state, the torque distribution of the motor in the torque zero-crossing state is reduced from the source in the front section of the torque link by adjusting the torque distribution ratio, and the torque distribution is partially overlapped to the motor not in the torque zero-crossing state, so that the response of the vehicle to Tip-in operation in the torque zero-crossing stage is improved, the response of the vehicle accords with the expectation of a driver, and the drivability of the vehicle and the driving experience of the driver are improved.
It should be understood that, although the steps in the flowchart of fig. 1 are shown in sequence as indicated by the arrows, the steps are not necessarily performed in sequence as indicated by the arrows. The steps are not strictly limited to the order of execution unless explicitly recited herein, and the steps may be executed in other orders. Moreover, at least some of the steps in fig. 1 may include multiple sub-steps or stages that are not necessarily performed at the same time, but may be performed at different times, nor do the order in which the sub-steps or stages are performed necessarily performed in sequence, but may be performed alternately or alternately with at least a portion of other steps or sub-steps of other steps.
In one embodiment, as shown in FIG. 2, there is provided a torque control apparatus based on torque split ratio adjustment, comprising:
The parameter acquisition unit is used for acquiring the target torque, the original distribution ratio, the original front motor torque and the original rear motor torque of the whole vehicle when receiving the rapid accelerator stepping operation initiated by a driver;
The torque zero-crossing state judging unit is used for judging whether the front motor is in a torque zero-crossing state according to the original torque of the front motor and the requested torque of the front motor;
The first adjusting unit is used for adjusting the original distribution ratio to obtain a first target distribution ratio through the original torque of the front motor, the request torque of the front motor and the target torque of the whole vehicle if the front motor is in a torque zero crossing state and the rear motor is not in a torque zero crossing state;
and the second adjusting unit is used for adjusting the original distribution ratio to obtain a second target distribution ratio through the original torque of the rear motor, the requested torque of the rear motor and the target torque of the whole vehicle if the rear motor is in the torque zero crossing state and the front motor is not in the torque zero crossing state, distributing the target torque of the whole vehicle according to the second target distribution ratio to obtain a target torque of the second front motor and a target torque of the second rear motor so as to reduce the torque distribution of the rear motor and increase the torque distribution of the front motor.
In a specific embodiment, the first adjusting unit is configured to adjust the original distribution ratio to obtain a first target distribution ratio by using the original front motor torque, the front motor requested torque and the target whole vehicle torque, and the first adjusting unit is configured to obtain a front motor unsolicited torque according to a difference between the original front motor torque and the front motor requested torque, calculate a first torque distribution ratio according to the original front motor torque, the front motor unsolicited torque, the target whole vehicle torque and a preset front axle transmission ratio, compare the first torque distribution ratio with the original distribution ratio, and take a maximum one of the first torque distribution ratio and the original distribution ratio as the first target distribution ratio.
In a preferred embodiment, before the step of adjusting the original distribution ratio to obtain a first target distribution ratio by the front motor original torque, the front motor request torque and the whole vehicle target torque, the first adjusting unit is further configured to obtain a preset first torque threshold, compare the front motor unsolicited torque with the first torque threshold, and if the front motor unsolicited torque is greater than the first torque threshold and the whole vehicle target torque is greater than zero, perform the step of adjusting the original distribution ratio to obtain a first target distribution ratio by the front motor original torque, the front motor request torque and the whole vehicle target torque.
In a specific embodiment, the second adjusting unit is configured to adjust the original distribution ratio to obtain a second target distribution ratio by the original rear motor torque, the requested rear motor torque and the target whole vehicle torque, and the second adjusting unit is configured to obtain a rear motor unsolicited torque according to a difference between the original rear motor torque and the requested rear motor torque, calculate a second torque distribution ratio according to the original rear motor torque, the unsolicited rear motor torque, the target whole vehicle torque and a preset rear axle transmission ratio, and compare the second torque distribution ratio with the original distribution ratio, and use a minimum one of the second torque distribution ratio and the original distribution ratio as the second target distribution ratio.
In a preferred embodiment, before the step of adjusting the original distribution ratio to obtain a second target distribution ratio by the rear motor original torque, the rear motor request torque and the vehicle target torque, the second adjusting unit is further configured to obtain a preset second torque threshold, compare the rear motor unsolicited torque with the second torque threshold, and if the rear motor unsolicited torque is greater than the second torque threshold and the vehicle target torque is greater than zero, perform the step of adjusting the original distribution ratio to obtain a second target distribution ratio by the rear motor original torque, the rear motor request torque and the vehicle target torque.
In a specific embodiment, the torque zero crossing state judging unit is configured to judge whether the front motor is in a torque zero crossing state according to the front motor original torque and the front motor request torque, and includes obtaining a preset third torque threshold and a preset fourth torque threshold, and judging whether the front motor original torque is greater than the third torque threshold and whether the front motor request torque is greater than the fourth torque threshold; if so, setting the set value of the front motor as a preset first value, if not, setting the set value of the front motor as a preset second value, collecting the current vehicle speed, obtaining the unsolicited torque of the front motor according to the difference between the original torque of the front motor and the requested torque of the front motor, obtaining a preset fifth torque threshold value, a sixth torque threshold value and a vehicle speed threshold value, judging whether the original torque of the front motor is smaller than the third torque threshold value, whether the requested torque of the front motor is larger than the fifth torque threshold value, whether the unsolicited torque of the front motor is smaller than the sixth torque threshold value and whether the current vehicle speed is smaller than the vehicle speed threshold value, if so, setting the reset value of the front motor as the first value, if not, setting the reset value of the front motor as the second value, judging that the set value of the front motor is the first value and the reset value of the front motor is the second value, or judging that the set value of the front motor is the first value and the reset value of the front motor is the second value when the first value of the first motor is the second value and the reset value of the front motor is the first value, or when the set value of the front motor is the second value and the reset value of the front motor jumps from the first value to the second value, judging that the front motor is not in a torque zero crossing state.
In a specific embodiment, the step of determining whether the rear motor is in a torque zero-crossing state according to the rear motor original torque and the rear motor request torque includes determining whether the rear motor original torque is greater than the third torque threshold and the rear motor request torque is greater than the fourth torque threshold, if so, setting a value of the rear motor to the first value, if not, setting the value of the rear motor to the second value, obtaining a rear motor unsolicited torque according to a difference between the rear motor original torque and the rear motor request torque, determining whether the rear motor original torque is less than the third torque threshold, whether the rear motor request torque is greater than the fifth torque threshold, whether the rear motor unsolicited torque is less than the sixth torque threshold, and whether the current vehicle speed is less than the vehicle speed threshold, if so, resetting the value of the rear motor to the first value, if not, resetting the value of the rear motor to the second value is the second value, and if the value of the rear motor is the second value, resetting the value of the rear motor to the second value is the second value, and if the value is the second value, resetting the value is the value, and if the value is the second value is the value, and the value is set from the second value, and the value is set from the value, and judging that the rear motor is not in a torque zero crossing state.
Specific limitations regarding the torque control means based on the torque distribution ratio adjustment may be found in the above description of the torque control method based on the torque distribution ratio adjustment, and will not be described here. The various modules in the torque control apparatus described above based on torque split ratio adjustment may be implemented in whole or in part in software, hardware, and combinations thereof. The above modules may be embedded in hardware or may be independent of a processor in the computer device, or may be stored in software in a memory in the computer device, so that the processor may call and execute operations corresponding to the above modules.
In one embodiment, a computer readable storage medium is provided having a computer program stored thereon, which when executed by a processor, implements the steps of the torque control method based on torque split ratio adjustment as described in the above embodiments.
Those skilled in the art will appreciate that implementing all or part of the above described methods may be accomplished by way of a computer program stored on a non-transitory computer readable storage medium, which when executed, may comprise the steps of the embodiments of the methods described above. Any reference to memory, storage, database, or other medium used in embodiments provided herein may include non-volatile and/or volatile memory. The nonvolatile memory can include Read Only Memory (ROM), programmable ROM (PROM), electrically Programmable ROM (EPROM), electrically Erasable Programmable ROM (EEPROM), or flash memory. Volatile memory can include Random Access Memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in a variety of forms such as Static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double Data Rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link (SYNCHLINK) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), among others.
The technical features of the above embodiments may be arbitrarily combined, and all possible combinations of the technical features in the above embodiments are not described for brevity of description, however, as long as there is no contradiction between the combinations of the technical features, they should be considered as the scope of the description.
The above examples illustrate only a few embodiments of the application, which are described in detail and are not to be construed as limiting the scope of the application. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the application, which are all within the scope of the application. Accordingly, the scope of protection of the present application is to be determined by the appended claims.