Patent Application
20240356473
The present disclosure relates to the technical field of vehicles, and more particularly, to a damping control method for a vehicle, a vehicle controller, and a vehicle.
To solve a problem of vehicle vibration, the related art provides a control method for calculating a compensation torque depending on whether a change rate of a rotation speed of a motor is positive or negative. In the method, a change rate of a rotation speed within 100 ms is calculated, it is determined whether the change rate is positive or negative, and a threshold is determined. If an absolute value of the change rate is greater than 1200, a value in a range of 2 Nm to 5 Nm is correspondingly compensated. A control target of the method is a scenario in which an acceleration of a motor is zero. When the acceleration is not zero, a compensation torque is applied. Therefore, the method is applicable to only application scenarios of working points with a fixed rotation speed, and is inapplicable to a vehicle condition with frequent acceleration and deceleration.
Moreover, the related art further provides a method, in which an acceleration sensor is mounted to a vehicle to collect a vehicle acceleration in real time, and the vehicle acceleration is controlled to be close to a reference acceleration through a PID, so as to obtain a compensation torque of each driving wheel and superimpose the compensation torque to an original torque to achieve active damping. A problem of the method is that an additional acceleration sensor needs to be added, which increases costs for the vehicle.
In addition, the related art further provides a method for suppressing vibration during startup while ensuring vehicle acceleration performance by increasing a step size of a motor in response to a vehicle expected moment and adding a rotation speed feedback link to correct the vehicle expected moment. In the rotation speed feedback link of the method, a vehicle acceleration torque is calculated through a vehicle resistance torque and a vehicle traction torque. However, it is difficult to calculate and measure the vehicle resistance torque. Therefore, an entire transmission system model is unavailable. Moreover, the method requires to establish an accurate mathematical model for the transmission system. Since the transmission system has many components, and a parameter and a characteristic of each component are related to a working environment and a usage time, it is difficult to establish an accurate model that works throughout a lifecycle. Since the vehicle resistance torque cannot be estimated and the mathematical model for the transmission system is inaccurate, a vehicle vibration suppression effect of the method is greatly reduced.
A vehicle and a damping control method therefor, and a vehicle controller are provided. The method is applicable to a wide range of working conditions, is easy to implement and verify, and can effectively eliminate vehicle vibration at lower costs.
According to a first aspect, the present disclosure provides a damping control method for a vehicle. The vehicle includes a motor and a motor controller. The method includes: obtaining a rotation speed of the motor; filtering the rotation speed through a first low-pass filter to obtain a first filtered rotation speed, filtering the rotation speed through a second low-pass filter to obtain a second filtered rotation speed, and obtaining, by a vehicle controller, a rotation speed fluctuation value based on the first filtered rotation speed and the second filtered rotation speed; obtaining, by the vehicle controller, an active damping adjustment coefficient and an active damping clipped torque based on the rotation speed; obtaining, by the vehicle controller, an active damping torque based on the rotation speed fluctuation value, the active damping adjustment coefficient, and the active damping clipped torque; and controlling, by the motor controller, the motor based on the active damping torque.
According to the damping control method for a vehicle in the embodiments of the present disclosure, the rotation speed fluctuation value may be determined merely through the two low-pass filters based on a real-time rotation speed without a need to use a frequency, then the active damping torque is obtained based on the rotation speed fluctuation value, the active damping adjustment coefficient, and the active damping clipped torque, and then the motor is controlled through the motor controller based on the active damping torque. The method is applicable to a wide range of working conditions, is easy to implement and verify, and can effectively eliminate vehicle vibration at lower costs.
According to a second aspect, the present disclosure provides a vehicle controller, which includes a memory, a processor, and a computer program stored in the memory. The processor is configured to execute the computer program to implement the damping control method for a vehicle of the first aspect.
According to the vehicle controller in the embodiments of the present disclosure, the computer program corresponding to the damping control method for a vehicle stored therein is executed by the processor, so that vehicle vibration can be effectively eliminated at lower costs.
According to a third aspect, the present disclosure provides a vehicle, which includes a motor, a motor controller, and the vehicle controller of the second aspect.
According to the vehicle in the embodiments of the present disclosure, an architecture in which the motor controller and the above vehicle controller work in combination is implemented. The motor controller obtains a rotation speed of the motor and provides the rotation speed of the motor to the vehicle controller, the vehicle controller calculates a required active damping torque for the motor controller, and then the motor controller controls the motor based on the active damping torque. In this way, a communication delay time is reduced.
Part of additional aspects and advantages of the present disclosure is provided in the following description. The part will be apparent from the following description, or is learned by practice of the present disclosure.
A vehicle and a damping control method therefor, and a vehicle controller in embodiments of the present disclosure are described below with reference to
S101: A rotation speed of a motor is obtained.
In an embodiment, a motor controller may collect and calculate the rotation speed of the motor in real time through a resolver.
S102: Filtering is respectively performed on the rotation speed through a first low-pass filter and a second low-pass filter, to obtain a first filtered rotation speed and a second filtered rotation speed, and a rotation speed fluctuation value is obtained based on the first filtered rotation speed and the second filtered rotation speed, for example, by a vehicle controller.
That a rotation speed fluctuation value is obtained based on the first filtered rotation speed and the second filtered rotation speed may include the following steps. A difference between the first filtered rotation speed and the second filtered rotation speed is calculated, to obtain a first difference. A rotation speed fluctuation calculation coefficient is obtained, and a product of the rotation speed fluctuation calculation coefficient and the first difference is calculated, to obtain the rotation speed fluctuation value.
In an embodiment, referring to
For example, referring to
Then, a rotation speed fluctuation value Δn is calculated based on an equation of Δn=k1*(n1−n2). k1 is a rotation speed fluctuation calculation coefficient. In the solution of the present disclosure, the rotation speed fluctuation value may be determined through the two low-pass filters based on a real-time rotation speed without a need to use a frequency, and then an active damping torque that needs to be applied is determined. Compared with a conventional solution using a band-pass filtering requires to obtain a rotation speed and a frequency, the solution is applicable to any working condition (that is, can obtain a rotation speed fluctuation value in any frequency band, and is applicable to calculation of a rotation speed fluctuation value in any working condition).
S103: An active damping adjustment coefficient and an active damping clipped torque are obtained based on the rotation speed.
In an embodiment, since a vibration frequency of a transmission system of a vehicle is relatively low, and vibration in a low speed range has significant impact on comfort, in the present disclosure, different active damping adjustment coefficients CoefActiveDamp are set based on different rotation speed ranges. In a low-speed area, the active damping adjustment coefficient CoefActiveDamp is set to a first active damping adjustment coefficient CoefActiveDampOne, to apply a strong vibration suppression effect on the vehicle, which can effectively alleviate the vibration in the low-speed area. In a high-speed area, resonance and vibration of the vehicle do not easily occur. Therefore, the active damping adjustment coefficient CoefActiveDamp is set to a second active damping adjustment coefficient CoefActiveDampTwo. Even if resonance occurs, impact thereof is acceptable after filtering performed by the transmission system. In addition, in a transition region between the low-speed area and the high-speed area, the active damping adjustment coefficient CoefActiveDamp is linearly transitioned, so that an active damping torque TrqActiveDamp process can be smoothly transitioned without generating an adjustment oscillation.
In an example, that an active damping adjustment coefficient and an active damping clipped torque are obtained based on the rotation speed may include the following steps. A first active damping adjustment coefficient is used as the active damping adjustment coefficient if the rotation speed is less than a first active damping switching rotation speed. A second active damping adjustment coefficient is used as the active damping adjustment coefficient if the rotation speed is greater than a second active damping switching rotation speed. The first active damping switching rotation speed is less than the second active damping switching rotation speed. Linear interpolation calculation is performed on the first active damping adjustment coefficient and the second active damping adjustment coefficient based on a ratio relationship or a correlation among the rotation speed, the first active damping switching rotation speed, and the second active damping switching rotation speed to obtain the active damping adjustment coefficient, if the rotation speed is greater than or equal to the first active damping switching rotation speed and less than or equal to the second active damping switching rotation speed.
In an embodiment, referring to
The linear interpolation calculation is performed for two known points (x1, y1) and (x0, y0) (x ranging between x0 and x1) by successively calculating a distance of x to x0 and a ratio of the distance of x to x0 to a distance of x1 to x0 and multiplying the ratio by a distance of y1 to y0 to calculate a value of y corresponding to a point x, that is, y=y0+ (x1−x0)*(y1−y0)/(x1−x0). x is the rotation speed of the motor. x0 is the first active damping switching rotation speed. x1 is the second active damping switching rotation speed. y0 is the first active damping adjustment coefficient. y1 is the second active damping adjustment coefficient. y is active damping adjustment coefficient. The active damping adjustment coefficient may be obtained based on the above equation of y=y0+ (x−x0)*(y1−y0)/(x1−x0).
It should be noted that, the first active damping adjustment coefficient and the second active damping adjustment coefficient may be flexibly calibrated without a limitation on a magnitude relationship between the two.
In another example, that an active damping adjustment coefficient and an active damping clipped torque are obtained based on the rotation speed includes the following steps. A first active damping clipped torque value is used as the active damping clipped torque if the rotation speed is less than a first active damping switching rotation speed. A second active damping clipped torque value is used as the active damping clipped torque if the rotation speed is greater than a second active damping switching rotation speed. The first active damping switching rotation speed is less than the second active damping switching rotation speed. Linear interpolation calculation is performed on the first active damping clipped torque value and the second active damping clipped torque value based on a ratio relationship among the rotation speed, the first active damping switching rotation speed, and the second active damping switching rotation speed to obtain the active damping clipped torque, if the rotation speed is greater than or equal to the first active damping switching rotation speed and less than or equal to the second active damping switching rotation speed.
In an embodiment, referring to
It should be noted that, the first active damping clipped torque value and the second active damping clipped torque value may be flexibly calibrated without a limitation on a magnitude relationship between the two.
S104: An active damping torque is obtained based on the rotation speed fluctuation value, the active damping adjustment coefficient, and the active damping clipped torque.
In an example, step S104 may include the following steps. A target active damping torque is obtained based on the rotation speed fluctuation value and the active damping adjustment coefficient. The target active damping torque is clipped based on the active damping clipped torque, to obtain the active damping torque.
In an embodiment, referring to
Referring to
S105: The motor is controlled through the motor controller based on the active damping torque.
In an example, before the motor is controlled through the motor controller based on the active damping torque, the damping control method for a vehicle may further include the following steps. An initial active damping torque is obtained. The active damping torque is updated to 0 if an absolute value of the active damping torque is less than the initial active damping torque.
In an embodiment, referring to
In another example, before the motor is controlled through the motor controller based on the active damping torque, the damping control method for a vehicle may further include the following step. The active damping torque is updated to 0 if an active damping function disabling instruction is received.
In an embodiment, referring to
In summary, according to the damping control method for a vehicle, the rotation speed fluctuation value may be determined merely through the two low-pass filters based on a real-time rotation speed without a need to use a frequency, then the active damping torque is obtained based on the rotation speed fluctuation value, the active damping adjustment coefficient, and the active damping clipped torque, and then the motor is controlled through the motor controller based on the active damping torque. The method is applicable to a wide range of working conditions, is easy to implement and verify, and can effectively eliminate vehicle vibration at lower costs.
The present disclosure further provides a vehicle controller.
In an embodiment, the vehicle controller 100 controls an active damping function of a motor controller to act through calibration parameters (to be specific, active damping enable ActiveDampEnable, a first active damping adjustment coefficient CoefActiveDampOne, a second active damping adjustment coefficient CoefActiveDampTwo, a first active damping clipped torque value ActiveDampLimTrqOne, a second active damping clipped torque value ActiveDampLimTrqTwo, a first active damping switching rotation speed DampSpeedOne, a second active damping switching rotation speed DampSpeedTwo, a first filtering coefficient corresponding to a first low-pass filter, a second filtering coefficient L2 corresponding to a second low-pass filter, and an initial active damping torque T2), which improves a calculation precision.
According to the vehicle controller in the embodiments of the present disclosure, the computer program corresponding to the damping control method for a vehicle stored therein is executed by the processor, so that vehicle vibration can be effectively eliminated at lower costs.
The present disclosure further provides a vehicle.
In an embodiment, the motor controller 220 sends a rotation speed of the motor and a torque of the motor to the vehicle controller 100 through a CAN line. The vehicle controller 100 receives an operation mode (for example, an economic mode (ecology conservation optimization, ECO), a standard mode (NORMAL), or a sport mode (SPORT)), a throttle signal, a brake signal, an acceleration signal, a vehicle speed signal, the torque of the motor, the rotation speed of the motor, and various working state signals during operation of the vehicle 200. The vehicle controller calculates a target torque (which is sent by the vehicle controller 100 to the motor controller 220) based on the received signal and a throttle demand, and identifies an operating status of the vehicle to control a vehicle damping control parameter. The motor controller 220 responds to the target torque of the vehicle controller 100, and feeds back signals such as the rotation speed of the motor and the torque of the motor in real time.
According to the vehicle in the embodiments of the present disclosure, an architecture in which the motor controller and the above vehicle controller work in combination is implemented. To be specific, the motor controller obtains the rotation speed of the motor and provides the rotation speed of the motor to the vehicle controller, the vehicle controller calculates a required active damping torque for the motor controller, and then the motor controller controls the motor based on the active damping torque. In this way, a communication delay time is reduced.
It should be noted that, the logic and/or steps shown in the flowcharts or described in other manners herein may be regarded as a sequence list of executable instructions for implementing logical functions, which may be implemented in any non-transitory computer-readable medium for use by or in combination with an instruction execution system, device, or apparatus (such as a computer-based system, a system including a processor, or other systems that can obtain instructions from the instruction execution system, device, or apparatus and execute the instructions). In this specification, a “non-transitory computer-readable medium” may be any device that can include, store, communicate, propagate, or transmit a program for use by or in combination with the instruction execution system, device, or apparatus. More examples (a non-exhaustive list) of the computer-readable storage medium include an electrical connection portion (an electronic device) with one or more wires, a portable computer case (a magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or a flash memory), an optical fiber device, and a portable compact disk read-only memory (CDROM). In addition, the non-transitory computer-readable medium even may be paper or other suitable media on which the program may be printed, because the program may be obtained electronically, for example, by optically scanning the paper or the other media, then performing editing, interpreting, or processing in other suitable manners if necessary, and then performing storage in a computer memory.
It should be understood that, parts of the present disclosure may be implemented by hardware, software, firmware, or a combination thereof. In the above implementations, multiple steps or methods may be implemented by software or firmware stored in a memory and executable by a proper instruction execution system. For example, if the multiple steps or methods are implemented by hardware, same as another implementation, the multiple steps or methods may be implemented through any of the following technologies known in the art or a combination thereof: a discrete logic circuit with a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit with a proper combinational logic gate circuit, a programmable gate array (PGA), a field programmable gate array (FPGA), and the like.
In the descriptions of the specification, a description with reference to terms such as “an embodiment”, “some embodiments”, “an example”, “a specific example”, or “some examples” means that features, structures, materials, or characteristics described with reference to the embodiment or the example are included in at least one embodiment or example of the present disclosure. In this specification, expressions of the above terms do not necessarily mean the same embodiment or example. In addition, the described features, structures, materials, or characteristics may be combined in a proper manner in any one or more embodiments or examples.
In the descriptions of this specification, orientation or position relationships indicated by the terms such as “center”, “longitudinal”, “transverse”, “length”, “width”, “thickness”, “up”, “down”, “front”, “rear”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “anticlockwise”, “axial direction”, “radial direction”, and “circumferential direction” are based on orientation or position relationships shown in the drawings, and do not indicate or imply that the mentioned device or element needs to have a particular orientation or be constructed and operated in a particular orientation. Therefore, such terms should not be construed as a limitation on the present disclosure.
In addition, the terms “first” and “second” are merely used for description, and cannot be construed as indicating or implying relative importance or implying a quantity of indicated technical features. Therefore, features defined with “first” and “second” may explicitly or implicitly include at least one of the features. In the descriptions of the present disclosure, unless explicitly specified, “multiple” means at least two, for example, two or three.
In the descriptions of this specification, unless otherwise specified, the terms such as “mount”, “connect”, “connection”, and “fix” should be understood in a broad sense. For example, the connection may be a fixed connection, a detachable connection, or an integral connection; or may be a mechanical connection or an electrical connection; or may be a direct connection, an indirect connection through an intermediate medium, internal communication between two elements, or an interaction relationship between two elements, unless otherwise explicitly specified. A person of ordinary skill in the art may understand meanings of the terms in the present disclosure based on situations.
In the present disclosure, unless otherwise explicitly specified and defined, that a first feature is “on” or “under” a second feature may mean that the first feature is in direct contact with the second feature or that the first feature is in indirect contact with the second feature through an intermediate medium. In addition, that the first feature is “above”, “over”, or “on” the second feature may mean that the first feature is directly above or obliquely above the second feature, or may merely mean that the first feature is at a higher horizontal position than the second feature. That the first feature is “below”, “under”, and “beneath” the second feature may mean that the first feature is directly below the second feature or obliquely below the second feature, or may merely mean that the first feature is at a lower horizontal position than the second feature.
Although the embodiments of the present disclosure are shown and described above, it may be understood that, the above embodiments are examples and should not be understood as a limitation on the present disclosure. A person of ordinary skill in the art may make changes, modifications, replacements, or variations to the above embodiments within the scope of the present disclosure.
| Number | Date | Country | Kind |
|---|---|---|---|
| 202210187935.X | Feb 2022 | CN | national |
This application is a continuation application of International Patent Application No. PCT/CN2023/078389, filed on Feb. 27, 2023, which is based on and claims priority to and benefits of Chinese Patent Application 202210187935.X, filed on Feb. 28, 2022. The entire content of all of the above-referenced applications is incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/CN2023/078389 | Feb 2023 | WO |
| Child | 18758734 | US |
