Vehicle control device and vehicle control method

Abstract

This control device (10) comprises, with respect to a vehicle (1) provided with a left drive system including a left axle (4L) and a left wheel (5L), and a right drive system including a right axle (4R) and a right wheel (5R), and also provided with a detection unit that detects the respective real speeds of the left drive system or a left drive source (2L) and the right drive system or a right drive source (2R): a calculation unit (11) that calculates a sum corresponding value corresponding to the sum of the two real speeds and a difference corresponding value corresponding to the difference between the two real speeds; a sum model which models the motion states of the left and right drive systems during straight traveling of the vehicle (1), and to which the sum corresponding value is applied; a difference model which models the motion states of the left and right drive systems during turning of the vehicle (1), and to which the difference corresponding value is applied; and a control unit (13) that controls the outputs of the left and right drive sources (2L, 2R) by using sum indication torque and difference indication torque separated into the sum model and the difference model and obtained from the sum model and the difference model, respectively.

Description

[Technical Field]

[0001] This invention relates to a vehicle control device and a vehicle control method for controlling a drive source mounted on a vehicle. [Background technology]

[0002] Conventionally, in vehicles equipped with multiple drive sources, a method is known for controlling the operating state of each drive source while suppressing vibrations in the drive transmission system, using a vehicle model that models the behavior of the drive transmission system (see Patent Document 1). [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2019-103249 [Overview of the project] [Problems that the invention aims to solve]

[0004] Incidentally, a conventional method for vibration suppression control is the use of a bandpass filter (BPF). This method extracts vibrations in a specific frequency band to be suppressed from the actual rotational speed of the drive source or the actual rotational speed of the axle or wheel, and then applies torque to suppress these vibrations, for example, to the left and right drive sources or left and right axles. However, the behavior of the drive force transmission system (e.g., vibration) differs between when the vehicle is moving straight and when it is turning, and the resonant frequencies also differ between when it is moving straight and when it is turning. Therefore, it is necessary to construct control to suppress vibrations that occur when the vehicle is moving straight and control to suppress vibrations that occur when it is turning, which presents the challenge of making the control configuration complex. In addition, for example, when performing control to suppress vibrations on one of the left and right axles, the control (output) also affects the other axle, making it difficult to implement appropriate vibration suppression control.

[0005] One of the objectives of this invention is to provide a vehicle control device and a vehicle control method that were devised in light of the above-mentioned problems, and that can suppress vibrations with a simple configuration without interfering with the left and right control systems. In addition to this objective, another objective of this invention is to achieve effects that cannot be obtained with conventional technology, derived from the various configurations shown in the "Modes for Carrying Out the Invention" described later. [Means for solving the problem]

[0006] The vehicle control device and control method disclosed can be implemented in the embodiments or specific examples disclosed below, and solve at least some of the above-mentioned problems. The disclosed vehicle control device comprises a left drive system including a left axle and left wheel to which power is transmitted from a left drive source, and a right drive system including a right axle and right wheel to which power is transmitted from a right drive source, and a detection unit that detects the actual speed of the left drive system or the left drive source and the actual speed of the right drive system or the right drive source, respectively, and includes a calculation unit that calculates a sum equivalent value corresponding to the sum of the two actual speeds and a difference equivalent value corresponding to the difference between the two actual speeds, a sum model that models the motion state of the left drive system and the right drive system when the vehicle is moving straight and to which the sum equivalent value is applied, a difference model that models the motion state of the left drive system and the right drive system when the vehicle is turning and to which the difference equivalent value is applied, and separates the two actual speeds into a sum mode and a difference mode by applying the sum equivalent value to the sum model and the difference equivalent value to the difference model, and the sum model In this, the vibration component of the sum mode is converted The obtained sum-indicating torque and the difference model In this, the vibration component of the difference mode is converted The system includes a control unit that controls the outputs of the left drive source and the right drive source using the obtained differential torque. The sum model used in the sum mode and the difference model used in the difference mode both include a bandpass filter for extracting vibration components. The sum model includes a bandpass filter for extracting a sum mode frequency band within a first predetermined range that includes the resonant frequencies of the left drive system and the right drive system when the vehicle is moving straight, and the difference model includes a bandpass filter for extracting a difference mode frequency band within a second predetermined range that includes the resonant frequencies of the left drive system and the right drive system when the vehicle is turning and that does not overlap with the sum mode frequency band.

[0007] The disclosed vehicle control method comprises a left drive system including a left axle and left wheel to which power is transmitted from a left drive source, and a right drive system including a right axle and right wheel to which power is transmitted from a right drive source, and includes a detection unit that detects the actual speed of the left drive system or the left drive source and the actual speed of the right drive system or the right drive source, respectively, and prepares in advance a sum model that models the motion state of the left drive system and the right drive system when the vehicle is moving straight, and a difference model that models the motion state of the left drive system and the right drive system when the vehicle is turning, calculates a sum equivalent value corresponding to the sum of the two actual speeds and a difference equivalent value corresponding to the difference between the two actual speeds, applies the sum equivalent value to the sum model and applies the difference equivalent value to the difference model, The two actual speeds mentioned above The sum mode is separated into a sum mode and a difference mode, and the sum model In this, the vibration component of the sum mode is converted The sum of the indicated torques is obtained, and the difference model is also obtained. In this, the vibration component of the difference mode is converted The differential torque is acquired, and the outputs of the left drive source and the right drive source are controlled using the sum torque and the differential torque. Furthermore, in this control method, the sum model used in the sum mode and the difference model used in the difference mode both include a bandpass filter for extracting vibration components, wherein the sum model includes a bandpass filter that extracts a sum mode frequency band in a first predetermined range that includes the resonant frequencies of the left drive system and the right drive system when the vehicle is moving straight, and the difference model includes a bandpass filter that extracts a difference mode frequency band in a second predetermined range that includes the resonant frequencies of the left drive system and the right drive system when the vehicle is turning and that does not overlap with the sum mode frequency band. [Effects of the Invention]

[0008] According to the disclosed vehicle control device and vehicle control method, by separating the sum model corresponding to the vehicle's straight-line movement and the difference model corresponding to its turning, vibrations can be suppressed with a simple configuration without causing interference between left and right control, even with different vibration characteristics during straight-line movement and turning. [Brief explanation of the drawing]

[0009] [Figure 1] This is a block diagram of a vehicle to which a control device has been applied. [Figure 2] This is a schematic diagram showing an example of the structure of a vehicle's drivetrain. [Figure 3] This is a block diagram showing the logic of the control method (vibration suppression control) implemented in the vehicle's control system. [Figure 4] This figure shows an example of a sum model. [Figure 5] This figure shows an example of the difference model in Figure 3. [Figure 6] This is a schematic diagram illustrating the relationship between the frequency band and response of a bandpass filter. [Modes for carrying out the invention]

[0010] The types of vehicles in which the disclosed vehicle control device and vehicle control method are used are, for example, engine vehicles (gasoline vehicles, diesel vehicles), electric vehicles, and hybrid vehicles, which are automobiles that run by driving the left and right wheels (left and right drive wheels) using at least one or more drive sources (internal combustion engines or motors), and preferably automobiles that run by driving the left and right wheels (left and right drive wheels) using multiple drive sources. Here, one of the multiple drive sources is called the left drive source, and one of the other drive sources is called the right drive source. Also, of the left and right wheels, the one located on the left side of the vehicle is called the left wheel, and the other is called the right wheel. The disclosed vehicle control device and vehicle control method can be used to control a vehicle that has a left drive system including a left axle and left wheel to which power is transmitted from the left drive source, and a right drive system including a right axle and right wheel to which power is transmitted from the right drive source.

[0011] The layouts of the left and right drive sources may or may not be set to correspond to the left-right direction, which is determined with respect to the direction of travel of the vehicle. Furthermore, the left and right drive systems may operate independently of each other, or they may be connected to each other via a transmission mechanism or a power distribution mechanism. The disclosed vehicle control device and vehicle control method can be used to control in-wheel motor vehicles in which each of the left and right wheels is driven by an individual motor, as well as to control torque vectoring vehicles in which the left and right wheels can transmit driving force and torque to each other. [Examples]

[0012] [1. Structure] The control device 10 in this embodiment is mounted on the vehicle 1 shown in Figure 1. The vehicle 1 comprises left and right wheels 5 arranged side by side in the width direction of the vehicle, a power distribution mechanism 3 (differential mechanism) that applies a torque difference to the left and right wheels 5, and a pair of motors 2 connected to the power distribution mechanism 3. In the figures of this embodiment, the letters L and R added to the numerical symbols indicate the location of the element to which the symbol relates (on the left or right side of the vehicle 1). For example, 5L represents one of the left and right wheels 5 located on the left side of the vehicle 1 (the left wheel), and 5R represents the other located on the right side (the right wheel). The longitudinal position of the left and right wheels 5 is irrelevant; they may be the front wheels or rear wheels of the vehicle 1.

[0013] Motor 2 (drive source) has the function of driving at least one of the front or rear wheels of vehicle 1, and may have the function of driving all four wheels. Of the pair of motors 2, the one located on the left is the left motor 2L (left drive source), and the other located on the right is the right motor 2R (right drive source). The left motor 2L and the right motor 2R operate independently of each other and can output different magnitudes of driving force individually. These motors 2 are connected to the power distribution mechanism 3 via a pair of separate reduction gears.

[0014] Vehicle 1 is equipped with a power distribution mechanism 3 that amplifies the torque difference between a pair of motors 2 and distributes it to the left and right wheels 5. The power distribution mechanism 3 in this embodiment is a differential mechanism with a yaw control function [AYC (Active Yaw Control) function] and is interposed between the axle 4 connected to the left wheel 5L (left axle 4L) and the axle 4 connected to the right wheel 5R (right axle 4R). The yaw control function adjusts the yaw moment by actively controlling the ratio of the driving force (driving torque) distributed between the left and right wheels 5, thereby stabilizing the attitude of vehicle 1. The power distribution mechanism 3 incorporates a planetary gear mechanism, a differential gear mechanism, and the like. The vehicle drive system including the pair of motors 2 and the power distribution mechanism 3 is also called a DM-AYC (Dual Motor AYC) system.

[0015] As shown in Figure 2, the power distribution mechanism 3 includes a pair of reduction mechanisms (gear train enclosed by dashed lines in Figure 2) and a gear shift mechanism (gear train enclosed by dashed lines in Figure 2) that reduce the rotational speed of the motor 2. The reduction mechanism is connected to the motor 2 rotation speed This mechanism increases torque by reducing the speed. The reduction ratio of the reduction mechanism is set appropriately according to the output characteristics and performance of motor 2. If the torque performance of motor 2 is sufficiently high, the reduction mechanism may be omitted. The transmission mechanism is a mechanism that amplifies the torque difference transmitted to each of the left and right wheels 5.

[0016] The gear shift mechanism of the power distribution mechanism 3 shown in Figure 2 includes a pair of planetary gear mechanisms. These planetary gear mechanisms have a structure in which the rotation axes of the planetary gears provided on each carrier are connected. Each carrier supports the planetary gear so that it can rotate and also supports the planetary gear so that it can revolve between the sun gear and the ring gear. In addition, the ring gear and sun gear of one planetary gear mechanism receive the driving force transmitted from the left and right motors 2, respectively. The driving force transmitted to the left and right wheels 5 is taken from the sun gear and carrier of the other planetary gear mechanism. Note that the structure of the power distribution mechanism 3 shown in Figure 2 is merely one example for realizing the yaw control function, and it is also possible to use other known structures.

[0017] As shown in Figure 1, each of the pair of motors 2 is electrically connected to a battery 7 via an inverter 6 (6L, 6R). The inverter 6 is a converter (DC-AC inverter) that converts between the power of the DC circuit on the battery 7 side (DC power) and the power of the AC circuit on the motor 2 side (AC power). The battery 7 is, for example, a lithium-ion secondary battery or a nickel-metal hydride secondary battery, and is a secondary battery capable of supplying a high voltage DC current of several hundred volts. When the motor 2 is operating, the DC power is converted to AC power by the inverter 6 and supplied to the motor 2. When the motor 2 is generating power, the generated power is converted to DC power by the inverter 6 and charged to the battery 7. The operating state of the inverter 6 is controlled by the control device 10.

[0018] The control device 10 is one of the electronic control units (ECUs) mounted on the vehicle 1. In a vehicle 1 equipped with a left drive system including the left axle 4L and left wheel 5L to which power is transmitted from the left motor 2L (left drive source) and a right drive system including the right axle 4R and right wheel 5R to which power is transmitted from the right motor 2R (right drive source), the control device 10 has the function of controlling the output of the left motor 2L and the right motor 2R, respectively.

[0019] The control device 10 incorporates a processor (central processing unit), memory (main memory), storage device, interface device, etc. (not shown), and these are connected to each other via an internal bus so that they can communicate with one another. The decisions and controls performed by the control device 10 are recorded and stored in memory as firmware or application programs, and when a program is executed, the contents of the program are expanded into the memory space and executed by the processor.

[0020] The control device 10 is connected to an accelerator pedal position sensor 14, a brake sensor 15, a steering angle sensor 16, a resolver 17, and a wheel speed sensor 18. The accelerator pedal position sensor 14 is a sensor that detects the amount the accelerator pedal is pressed (accelerator pedal position) and the speed at which it is pressed. The brake sensor 15 is a sensor that detects the amount the brake pedal is pressed (brake pedal stroke) and the speed at which it is pressed. The steering angle sensor 16 is a sensor that detects the steering angle (actual steering angle or steering angle) of the left and right wheels 5.

[0021] The resolvers 17 (17L, 17R) are sensors (detection units) that detect the actual angular velocity of the motor 2, and are individually provided for each of the pair of motors 2. The resolvers 17 output information about the rotation angle of the motor 2 as a two-phase AC voltage. The actual angular velocity of the motor 2 is determined from the change in these AC voltages over time. The wheel speed sensors 18 (18L, 18R) are sensors (detection units) that detect the actual angular velocity of the axle 4. The control device 10 controls the output of the pair of motors 2 (2L, 2R) by controlling the operating state of the inverter 6 (6L, 6R) based on the information detected by the various sensors 14 to 18 described above. In addition, the actual angular velocity of the motor 2 may be detected using other sensors (detection units such as Hall sensors and encoders) that have different internal structures and operating principles, instead of the resolvers 17.

[0022] Vehicle 1 is equipped with a detection unit that detects the actual speed of the left drive system or left motor 2L (hereinafter referred to as "left actual speed") and the actual speed of the right drive system or right motor 2R (hereinafter referred to as "right actual speed"). The actual speed referred to here includes, for example, the actual angular velocity of the axle 4, the actual angular velocity or actual wheel speed of the left and right wheels 5, the actual angular velocity of motor 2, and the angular velocity of motor 2 after it has been reduced by the reduction mechanism (reduced angular velocity). The detection unit is a device, equipment, or sensor that can detect the actual speed, for example, the resolver 17 or wheel speed sensor 18 mentioned above.

[0023] [2. Control device] Figure 3 is a block diagram showing the basic concept (logic) of the control performed by the control device 10 (vibration suppression control using the control method described as an embodiment). In Figure 3, "plant" refers to objects located upstream of each axle 4 in the power transmission path (such as motors 2 and shafts and gears included in the power transmission mechanism 3). In this control, the vibrations of the left and right drive systems are separated into vibrations when the vehicle 1 is moving straight and vibrations when the vehicle 1 is turning, with the former being treated as sum-mode vibrations and the latter as difference-mode vibrations. Then, torques to suppress vibrations are obtained for both the sum-mode and difference-mode vibrations, and the obtained torques are converted back to left and right representations before being output (instructed) to the left motor 2L and right motor 2R.

[0024] The memory of the control device 10 pre-stores a sum-mode vibration suppression model (hereinafter also simply called the "sum model") used in sum mode and a difference-mode vibration suppression model (hereinafter also simply called the "difference model") used in difference mode. In other words, in this control method, the sum model and the difference model are prepared first. The sum model is a model that models the motion state of the left drive system and the right drive system when the vehicle 1 is moving straight, and the difference model is a model that models the motion state of the left drive system and the right drive system when the vehicle 1 is turning. The sum model and the difference model are models related to vibration suppression.

[0025] Generally, the vibrations generated by vehicle 1 differ when moving straight and when turning, and their resonant frequencies also differ. Depending on the type of vehicle 1, for example, the resonant frequency when moving straight is about 6 Hz, while the resonant frequency when turning is lower, for example, about 2 Hz. Thus, in order to effectively suppress the vibrations that differ when vehicle 1 is moving straight (translational motion) and when it is turning (yaw motion), and to ensure that the vibration suppression controls (outputs) do not interfere with each other on the left and right sides, the system is separated into the two modes described above, and a model is provided for use in each mode. In other words, the sum model and difference model are models used to apply vibration suppression control in the straight and turning states, respectively, in response to the different resonant frequencies of straight and turning.

[0026] As shown in Figure 3, the sum model has a sum equivalent value ω SM The sum of the indicative torque T is applied to control the motor 2 when the vehicle 1 is moving straight (specifically, to suppress vibrations in the left and right drive systems). SV The output (derivation) is obtained. Similarly, the difference model has a difference equivalent value ω DM The differential instruction torque T is applied to control motor 2 during vehicle 1's turning (specifically, to suppress vibrations in the left and right drive systems). DV Output (derive) the sum equivalent value ω. SM This refers to the actual angular velocity ω of the left motor 2L, which is the left drive source. LM and the actual angular velocity ω of the right motor 2R, which is the right drive source. RMIt is a general term for values corresponding to the sum, and is also referred to as "sum mode motor angular velocity ω SM ". The value ω SM corresponding to the sum includes not only the simple sum, but also a value obtained by multiplying the sum by a predetermined coefficient and a value that is half of the sum (arithmetic mean value). Further, the value ω DM corresponding to the difference is a general term for values corresponding to the difference between the actual angular velocity ω LM of the left motor 2L and the actual angular velocity ω RM of the right motor 2R, and is also referred to as "difference mode motor angular velocity ω DM ". The value ω DM corresponding to the difference includes not only the simple difference, but also a value obtained by multiplying the difference by a predetermined coefficient.

[0027] Step A1 in FIG. 3 corresponds to a step (conversion step) of calculating a sum corresponding value ω LM , ω RM corresponding to the sum of the left actual speed and the right actual speed (for example, the sum of two actual angular velocities ω SM ). The sum corresponding value ω SM calculated in this step is applied to the sum model in step A3 in FIG. 3. As a result, an output (sum instruction torque T SV ) for suppressing vibration of the left drive system and the right drive system when the vehicle 1 is moving straight is obtained, and the vibration state of the vehicle 1 related to straight movement is effectively suppressed. Further, step A2 in FIG. 3 corresponds to a step (conversion step) of calculating a difference corresponding value ω LM , ω RM corresponding to the difference between the left actual speed and the right actual speed (for example, the difference between two actual angular velocities ω DM ). The difference corresponding value ω DM calculated in this step is applied to the difference model in step A4 in FIG. 3. As a result, an output (difference instruction torque T DV ) for suppressing vibration of the left drive system and the right drive system when the vehicle 1 is turning is obtained, and the vibration state of the vehicle 1 related to turning is effectively suppressed.

[0028] Step A5 in FIG. 3 is an instruction torque (right instruction torque T SV ) output to the right motor 2R from the sum instruction torque T DV obtained from the sum model and the difference instruction torque T RVThis corresponds to the process of calculating the right-indicating torque T in this process (inverse conversion process). RV This is the torque command value to suppress vibration of the right motor 2R. Also, step A6 in Figure 3 is the sum command torque T obtained from the sum model. SV The differential indicated torque T obtained from the differential model DV Therefore, the instruction torque (left instruction torque T) is output to the left motor 2L. LV This corresponds to the process of calculating the left-indicating torque T in this process (reverse conversion process). LV This is the torque command value used to suppress vibrations in the left motor 2L.

[0029] Thus, the vibration suppression control in this embodiment controls the actual speed of the motor 2 (for example, the actual angular velocity ω LM ,ω RM ) From, torque T to suppress vibration LV ,T RV We find the torque T LV ,T RV This is a feedback (FB) control that aims to suppress vibrations by outputting to motor 2 (in other words, bringing the vibration closer to a target value of 0). Furthermore, in this FB control, an independent sum model and a difference model are provided, and the actual speed (for example, the actual angular velocity ω) LM ,ω RM The system is separated into a sum mode, which extracts only the straight-line component, and a difference mode, which extracts only the turning component. This allows for the suppression of vibrations during straight-line driving by using a sum instruction torque T. SV The differential torque T is designed to suppress vibrations during turns. DV It is easy to impart different characteristics to the left and right indicated torque T LV ,T RV They do not interfere with each other.

[0030] Next, we will describe the specific configuration for implementing the above control. As shown in Figure 1, the control device 10 is equipped with a calculation unit 11, a storage unit 12, and a control unit 13. These elements are a convenient classification of the functions of the control device 10. These elements may be described as independent programs to realize the functions of each element. Alternatively, multiple elements may be combined and described as a single composite program.

[0031] The calculation unit 11 calculates the sum equivalent value ω based on the actual speed of the left drive system or left motor 2L and the corresponding actual speed of the right drive system or right motor 2R. SM and the equivalent difference ω DM This calculates the value of the left resolver 17L (actual angular velocity ω). The calculation unit 11 of this embodiment calculates the value of the left resolver 17L (actual angular velocity ω). LM ) and the corresponding detected value of the right resolver 17R (actual angular velocity ω RM Based on this, the sum equivalent value ω SM and the equivalent difference ω DM The following calculates the two real angular velocities ω. LM ,ω RM Half of the sum is the equivalent value of the sum mode motor angular velocity ω SM ) and the two real angular velocities ω LM ,ω RM Half of the difference is the difference equivalent value (difference mode motor angular velocity ω DM The calculation formula for the case of ) is shown below.

[0032]

number

[0033] The memory unit 12 stores the sum model and difference model described above. In this embodiment, the sum model is given characteristics that make it difficult for resonance to occur during straight-line driving (characteristics that do not include the resonant frequency component during straight-line driving), and the difference model is given characteristics that make it difficult for resonance to occur during turning (characteristics that do not include the resonant frequency component during turning). By controlling the resonance frequencies of the sum model and difference model in this way, vibration suppression becomes possible under all driving conditions.

[0034] Both the sum model and the difference model in this embodiment include a bandpass filter (hereinafter referred to as "BPF") for extracting vibration components. The BPF extracts the resonant frequency component as the vibration component to be suppressed, and the vibration components to be extracted are determined by the BPF of the sum model and the BPF of the difference model, respectively.

[0035] Here, an example of the sum model 20 is shown in Figure 4, and an example of the difference model 30 is shown in Figure 5. The sum model 20 in Figure 4 is the resonant frequency RF of the left and right drive systems when vehicle 1 is moving straight. S The BPF21,22 extracts a sum mode frequency band within a first predetermined range, which includes the resonant frequency RF. S ±1Hz (i.e., "RF") S -1" or greater and "RF" S It is defined as "+1" or less. In this case, for example, the resonant frequency RF when propagating in a straight line. S If the frequency is 6Hz, then the sum mode frequency band in the first predetermined range will be 5Hz to 7Hz.

[0036] This sum model 20 includes a BPF 21 that extracts vibration components from the sum equivalent value, and a BPF 22 that extracts vibration components from the differential value of the sum equivalent value. The sum mode frequency bands of the two BPFs 21 and 22 may be the same or different. The sum model 20 also includes a first multiplier 23 and 24 that multiplies the vibration components output from BPFs 21 and 22 by a gain to convert them into torque, a second multiplier 25 and 26 that converts the converted torque into a torque for vibration suppression, and an adder 27 that adds the two vibration suppression torques together. In other words, the sum model 20 includes FB control consisting of P control (proportional BPF control) and D control (differential BPF control). The torque output from the adder 27 is the sum indicated torque T. SV That is the case.

[0037] The difference model 30 shown in Figure 5 is configured similarly to the sum model 20. That is, this difference model 30 is the resonant frequency RF of the left and right drive systems during the turning of vehicle 1. CThe BPF31,32 extracts the difference mode frequency band of a second predetermined range, including the resonant frequency RF. The second predetermined range is, for example, the same as the first predetermined range, the resonant frequency RF. C ±1Hz (i.e., "RF") C -1" or greater and "RF" C It is defined as "+1" or less. In this case, for example, the resonant frequency RF during rotation. C If the first predetermined range is 2 Hz, then the difference mode frequency band of the second predetermined range will be 1 Hz to 3 Hz. Note that the first predetermined range and the second predetermined range do not necessarily have to be the same.

[0038] As shown by the black arrows in Figure 6, the sum mode frequency band (sum mode BPF band) and the difference mode frequency band (difference mode BPF band) are set so as not to overlap. Note that the BPF band shown by the white arrows in Figure 6 is a comparative example and is the frequency band set when conventional vibration suppression control is performed, i.e., when vibration suppression control is performed on the left and right sides separately. As shown by the white arrows, the vibration during straight-line propagation (RF S (Nearby) Vibration during turning (RF C If you want to set up a BPF to suppress (nearby) frequencies, you will need to use a BPF with a wide frequency band.

[0039] As shown in Figure 6, where the horizontal axis is labeled "Impact on Responsiveness," it is known that the lower the resonance frequency, the greater the impact on responsiveness (especially acceleration responsiveness). Therefore, if the frequency band of the BPF is widened as in conventional methods, there is a problem in that responsiveness (especially acceleration responsiveness during starting and acceleration) decreases. In contrast, as shown by the black arrows, in this method, the sum mode frequency band (sum mode BPF band) and the difference mode frequency band (difference mode BPF band) are set so that they do not overlap with each other, so that vibrations during straight-line driving and vibrations during turning are separated and extracted, and the frequency band can be set to the minimum, thus reducing the impact on responsiveness. Also, since vehicle 1 usually accelerates while driving straight rather than turning, the sum mode frequency band that extracts vibrations during straight-line driving is set to the higher side of the resonance frequency, thereby improving acceleration responsiveness.

[0040] As shown in Figure 5, the difference model 30 includes a BPF 31 that extracts vibration components from the difference equivalent value and a BPF 32 that extracts vibration components from the differential value of the difference equivalent value. The difference mode frequency bands of the two BPFs 31 and 32 may be the same or different. The difference model 30 also includes a first multiplier 33, 34 that multiplies the vibration components output from BPFs 31 and 32 by a gain to convert them into torque, a second multiplier 35, 36 that converts the converted torque into a torque for vibration suppression, and an adder 37 that adds the two torques for vibration suppression together. In other words, the difference model 30 also includes FB control consisting of P control (proportional BPF control) and D control (differential BPF control). The torque output from the adder 37 is the difference indicated torque T. DV That is the case.

[0041] The control unit 13 adds the sum equivalent value ω calculated by the calculation unit 11 to the sum model stored in the memory unit 12. SM In addition, the difference equivalent value ω calculated by the calculation unit 11 is applied to the above difference model stored in the memory unit 12. DM By applying this, the two real angular velocities ω LM ,ω RM The sum mode and the difference mode are separated. Then, the control unit 13 receives the sum instruction torque T from the sum mode. SV The differential indicated torque T obtained from the differential model DV The outputs of the left motor 2L and the right motor 2R are controlled using this method.

[0042] Specifically, the control unit 13 controls the sum-indicated torque T SV and differential indicated torque T DV Torque T LV and right indicator torque T RV The sum of the indicated torque T is calculated and the left and right motors 2 are controlled. Here, the sum of the indicated torque T is calculated according to the calculation method of the calculation unit 11. SV From the differential indicated torque T DV Half of the value obtained by subtracting is the left indicator torque T. LV It is output as the sum of the indicated torque T SV and differential indicated torque T DV Half of the sum of these is the right-indicated torque T RVis output as. Note that the left and right command torques T LV , T RV obtained here are torques for the purpose of vibration suppression. Separately from these, the drive torques for driving the left motor 2L and the right motor 2R are obtained separately and output (commanded) to the left motor 2L and the right motor 2R.

[0043] When the control unit 13 uses a sum model and a difference model including FB control consisting of P control and D control as shown in FIGS. 4 and 5, in addition to the sum equivalent value and the difference equivalent value, the differential value of the sum equivalent value and the differential value of the difference equivalent value are also used to separate into a sum mode and a difference mode. In FIGS. 4 and 5, a sum model and a difference model including FB control consisting of P control and D control are illustrated, but only P control may be used, or I control (integral BPF control) may be further included.

[0044] [3. Effects] (1) The above control device 10 includes a calculation unit 11, a sum model and a difference model, and a control unit 13. The calculation unit 11 calculates a sum equivalent value ω LM , ω RM corresponding to the sum of the two actual angular velocities ω SM and calculates a difference equivalent value ω LM , ω RM corresponding to the difference between the two actual angular velocities ω DM . The sum model models the motion states of the left drive system and the right drive system when the vehicle 1 is going straight, and the sum equivalent value ω SM is applied. The difference model models the motion states of the left drive system and the right drive system when the vehicle 1 is turning, and the difference equivalent value ω DM is input.

[0045] The control unit 13 applies the sum equivalent value ω SM to the sum model and the difference equivalent value ω DM to the difference model, so that the sum mode with only the straight-ahead component from the two actual angular velocities ω LM , ω RM and the two actual angular velocities ω LM , ω RMIt is separated into a differential mode containing only the turning component. Then, the sum instruction torque T obtained from the sum model is obtained. SV The differential indicated torque T obtained from the differential model DV The left and right drive sources are controlled using these.

[0046] This configuration allows for vibration suppression without interference between left and right control, addressing the different vibration characteristics during straight-line travel and turning. Furthermore, by separating the sum model corresponding to straight-line travel and the difference model corresponding to turning, and constructing them as independent models, complex non-interference control becomes unnecessary, resulting in a simpler design and enabling vibration suppression with a more streamlined configuration.

[0047] (2) In the above embodiment, both the sum model and the difference model include a bandpass filter that extracts vibration components. With this configuration, a torque T is created that suppresses vibrations in a specific frequency band from the vibrations generated when the vehicle 1 is moving straight and when it is turning, using a simple configuration. SV ,T DV This can be achieved. Therefore, the vibration suppression effect can be enhanced.

[0048] (3) In the example models shown in Figures 4 and 5, the control unit 13 separates the sum mode and difference mode using not only the sum equivalent value and the difference equivalent value, but also their derivative values. By using the sum model and difference model, which include FB control consisting of P control and D control, the vibration component can be brought closer to the target value of 0 more quickly, and the vibration suppression effect can be further enhanced.

[0049] (4) Furthermore, the Japanese model determines the resonant frequency RF of the left drive system and the right drive system during straight-line driving. S The BPF includes a first predetermined range of sum mode frequency bands including (e.g., 6Hz), and the difference model includes the resonant frequency RF of the left and right drive systems during rotation. CThe bandpass filter (BPF) may include a second predetermined range of difference mode frequency bands, including (for example, 2 Hz). The sum mode frequency band and the difference mode frequency band are set so as not to overlap with each other, thereby allowing only the vibrations of the minimum necessary frequency bands to be extracted, as shown in Figure 6. Therefore, in addition to the vibration suppression effect, responsiveness (especially acceleration responsiveness) can be improved.

[0050] [4. Others] The above embodiments are merely illustrative examples, and there is no intention to exclude various modifications or applications of techniques not explicitly stated in these embodiments. Each configuration of these embodiments can be modified in various ways without departing from their intended purpose. Furthermore, each configuration of these embodiments can be selected or combined as needed.

[0051] For example, the method and values ​​for setting the BPF frequency band included in each model are just examples, and the BPF frequency band may be set using methods other than those described above. Also, the specific configuration of each model is not limited to those shown in Figures 4 and 5.

[0052] In the above embodiment, a vehicle 1 equipped with a pair of motors 2 as a drive source was illustrated, but an internal combustion engine may be used instead of the motors 2, and the specific type of drive source is not limited. Furthermore, although a vehicle 1 equipped with a vehicle drive system (DM-AYC device) including a pair of motors 2 and a power distribution mechanism 3 was illustrated, the concepts of the sum model and difference model are applicable to any vehicle, and can be applied to vehicles without a power distribution mechanism 3 or to in-wheel motor vehicles, for example. At a minimum, any vehicle equipped with a left drive system including the left axle and left wheel to which power is transmitted from the left drive source, and a right drive system including the right axle and right wheel to which power is transmitted from the right drive source, can implement the same control as in the above embodiment and obtain the same operation and effect as in the above embodiment.

[0053] [5. Addendum] The following notes are disclosed regarding the above embodiments and modifications. [Note 1] A vehicle control method comprising a left drive system including a left axle and left wheel to which power is transmitted from a left drive source, and a right drive system including a right axle and right wheel to which power is transmitted from a right drive source, and comprising a detection unit for detecting the actual speed of the left drive system or the left drive source and the actual speed of the right drive system or the right drive source, respectively, A sum model that models the motion of the left drive system and the right drive system when the vehicle is moving straight, and a difference model that models the motion of the left drive system and the right drive system when the vehicle is turning are prepared in advance. A sum equivalent value corresponding to the sum of the two aforementioned actual speeds and a difference equivalent value corresponding to the difference between the two aforementioned actual speeds are calculated. By applying the sum equivalent value to the sum model and the difference equivalent value to the difference model, The two actual speeds mentioned above The system is separated into a sum mode and a difference mode, and the sum instruction torque is obtained from the sum model, and the difference instruction torque is obtained from the difference model. The outputs of the left drive source and the right drive source are controlled using the sum instruction torque and the difference instruction torque. A vehicle control method characterized by the following features.

[0054] [Note 2] Both the sum model and the difference model include a bandpass filter for extracting vibrational components. A vehicle control method as described in Appendix 1, characterized by the features described herein.

[0055] [Note 3] The derivatives of the sum equivalent value and the difference equivalent value are also used to separate the sum mode and the difference mode. A vehicle control method as described in Appendix 1 or 2, characterized by the above.

[0056] [Note 4] The sum model includes a bandpass filter that extracts a sum mode frequency band within a first predetermined range, which includes the resonant frequencies of the left drive system and the right drive system when the vehicle is moving straight. The difference model includes a bandpass filter that extracts a difference mode frequency band that is in a second predetermined range including the resonant frequencies of the left drive system and the right drive system during vehicle turning, and that does not overlap with the sum mode frequency band. A vehicle control method as described in Appendix 2 or Appendix 3 referencing Appendix 2, characterized in that [Industrial applicability]

[0057] This technology is applicable to the manufacturing industry of vehicle control systems, and also to the manufacturing industry of vehicles equipped with such control systems. [Explanation of symbols]

[0058] 1 vehicle 2. Motor (drive source) 3 Power distribution mechanism 4 axles 5 Left and right wheels 6 Inverters 7 Batteries 10 Control device 11 Calculation Section 12 Storage section 13 Control Unit 14. Accelerator position sensor 15 Brake Sensor 16. Steering angle sensor 17, 17L, 17R resolver (detection unit) 18, 18L, 18R Wheel speed sensor (detection unit) 20 Japanese Model 21,22 Bandpass filter, BPF 23,24 First Multiplication Section 25,26 Second Multiplication Section 27 Addition section 30 Difference Model 31,32 Bandpass filter, BPF 33,34 First Multiplication Section 35,36 Second multiplication section 37 Addition section

Claims

1. A vehicle control device comprising a left drive system including a left axle and left wheel to which power is transmitted from a left drive source, and a right drive system including a right axle and right wheel to which power is transmitted from a right drive source, and comprising a detection unit for detecting the actual speed of the left drive system or the left drive source and the actual speed of the right drive system or the right drive source, respectively, A calculation unit that calculates a sum equivalent value corresponding to the sum of the two actual speeds and a difference equivalent value corresponding to the difference between the two actual speeds, A sum model that models the motion state of the left drive system and the right drive system when the vehicle is moving straight, to which the sum equivalent value is applied, A difference model that models the motion state of the left drive system and the right drive system during the turning of the vehicle, to which the difference equivalent value is applied, The system includes a control unit that applies the sum equivalent value to the sum model and the difference equivalent value to the difference model to separate the two actual speeds into a sum mode and a difference mode, and controls the outputs of the left drive source and the right drive source using the sum instruction torque obtained by converting the vibration component of the sum mode in the sum model and the difference instruction torque obtained by converting the vibration component of the difference mode in the difference model, The sum model used in the sum mode and the difference model used in the difference mode both include a bandpass filter for extracting vibration components. The sum model includes a bandpass filter that extracts a sum mode frequency band within a first predetermined range, which includes the resonant frequencies of the left drive system and the right drive system when the vehicle is moving straight. The difference model includes a bandpass filter that extracts a difference mode frequency band that is in a second predetermined range including the resonant frequencies of the left drive system and the right drive system during vehicle turning, and that does not overlap with the sum mode frequency band. A vehicle control device characterized by the following features.

2. The control unit separates the sum mode and the difference mode using the derivative values ​​of the sum equivalent value and the derivative values ​​of the difference equivalent value. A vehicle control device according to claim 1, characterized in that

3. A vehicle control method comprising a left drive system including a left axle and left wheel to which power is transmitted from a left drive source, and a right drive system including a right axle and right wheel to which power is transmitted from a right drive source, and comprising a detection unit for detecting the actual speed of the left drive system or the left drive source and the actual speed of the right drive system or the right drive source, respectively, A sum model that models the motion of the left drive system and the right drive system when the vehicle is moving straight, and a difference model that models the motion of the left drive system and the right drive system when the vehicle is turning are prepared in advance. A sum equivalent value corresponding to the sum of the two aforementioned actual speeds and a difference equivalent value corresponding to the difference between the two aforementioned actual speeds are calculated. The sum equivalent value is applied to the sum model and the difference equivalent value is applied to the difference model to separate the two actual speeds into a sum mode and a difference mode, the vibration component of the sum mode is converted in the sum model to obtain the sum instruction torque, and the vibration component of the difference mode is converted in the difference model to obtain the difference instruction torque. The control method involves controlling the outputs of the left drive source and the right drive source using the sum-indicated torque and the difference-indicated torque, The sum model used in the sum mode and the difference model used in the difference mode both include a bandpass filter for extracting vibration components. The sum model includes a bandpass filter that extracts a sum mode frequency band within a first predetermined range, which includes the resonant frequencies of the left drive system and the right drive system when the vehicle is moving straight. The difference model includes a bandpass filter that extracts a difference mode frequency band that is in a second predetermined range including the resonant frequencies of the left drive system and the right drive system during vehicle turning, and that does not overlap with the sum mode frequency band. A vehicle control method characterized by the following features.

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