control device

Abstract

This technology is used to calculate vibration damping torque and realizes vibration damping technology that is less susceptible to errors in estimated values. [Solution] The vibration control unit 10 of the control device controls the rotational electric machine torque command value T mg A torque command value acquisition unit 11 acquires the torque command value, and a detected value ω of the rotational speed of the rotating electric machine. mg The system includes a detection value acquisition unit 12 that acquires the rotational speed of the rotating electric machine ω, a wheel speed estimation unit 13 that estimates the wheel speed, and a vibration damping torque calculation unit 14 that calculates the vibration damping torque ΔT. The wheel speed estimation unit 13 acquires the detected value ω of the rotational speed of the rotating electric machine mg and the torque command value T of the rotating electric machine mg Based on this, the estimated value of the wheel speed ω tire The vibration damping torque calculation unit 14 calculates the rotational speed of the rotating electric machine ω. mg and the estimated value of wheel speed ω tire The torque corresponding to the speed difference when converted to the same position in the power transmission system is calculated as the vibration damping torque ΔT.

Description

Technical Field

[0001] The present invention relates to a control device that controls a vehicle including a rotating electric machine and a power transmission system that transmits the driving force of the rotating electric machine to wheels.

Background Art

[0002] An example of such a control device as described above is disclosed in Japanese Patent Laid-Open No. 2018-186627 (Patent Document 1). Hereinafter, in the description of the background art, reference signs shown in parentheses are those of Patent Document 1. The control device (70) of Patent Document 1 is configured to estimate disturbance torque using an observer, and increase or decrease a target torque (Tm_ref) of a rotating electric machine (50) in accordance with an estimated disturbance torque (ΔT_est), which is an estimated value of the disturbance torque, in order to suppress vibration caused by the disturbance torque. Specifically, as described in paragraphs 0055 to 0059 of Patent Document 1, the control device (70) is configured to set a value obtained by multiplying a differential value of the estimated disturbance torque (ΔT_est) by a gain as a torque adjustment amount (Tm_adj), and add the torque adjustment amount (Tm_adj) to the target torque (Tm_ref) to calculate a torque command (Tm_tgt).

Prior Art Literature

Patent Literature

[0003]

Patent Document 1

Summary of the Invention

Problem to be Solved by the Invention

[0004] As described above, in the technology described in Patent Document 1, a torque obtained by multiplying a differential value of the estimated disturbance torque by a gain is calculated as a vibration damping torque for reducing vibration occurring in the vehicle (referred to as a torque adjustment amount in Patent Document 1). Therefore, the technology is easily affected by errors in the estimated value (the estimated value of disturbance torque in Patent Document 1) used to calculate the vibration damping torque, and there is room for improvement in this respect in the technology described in Patent Document 1.

[0005] Therefore, there is a need to realize vibration control technology that is less susceptible to errors in the estimated values ​​used to calculate vibration control torque. [Means for solving the problem]

[0006] The control device according to this disclosure is a control device for controlling a vehicle comprising a rotating electric machine and a power transmission system for transmitting the driving force of the rotating electric machine to wheels, and comprises a vibration damping control unit that causes the rotating electric machine to output a vibration damping torque to reduce vibrations occurring in the vehicle, the vibration damping control unit comprising a torque command value acquisition unit that acquires a rotating electric machine torque command value which is the value of the torque commanded to the rotating electric machine, a detection value acquisition unit that acquires a detection value of the rotating electric machine rotation speed which is the rotation speed of the rotating electric machine, a wheel speed estimation unit that estimates the wheel speed which is the rotation speed of the wheels, and a vibration damping torque calculation unit that calculates the vibration damping torque, the wheel speed estimation unit calculates the estimated value of the wheel speed based on the detected value of the rotating electric machine rotation speed and the rotating electric machine torque command value, and the vibration damping torque calculation unit calculates the vibration damping torque as a torque corresponding to the speed difference between the detected value of the rotating electric machine rotation speed and the estimated value of the wheel speed when converted to the same position in the power transmission system.

[0007] In this configuration, the torque corresponding to the speed difference between the detected rotational speed of the rotating electric machine and the estimated wheel speed, converted to the same position in the power transmission system, is calculated as vibration damping torque to reduce vibrations occurring in the vehicle. Here, the speed difference used in calculating the vibration damping torque is not an estimated value in its entirety; rather, only one of the two values ​​from which the speed difference is calculated (specifically, the wheel speed) is an estimated value, and the other (specifically, the rotational speed of the rotating electric machine) is a detected value. Therefore, the error in the estimated value used in calculating the vibration damping torque can be limited to the error in the wheel speed, and as a result, it is easier to ensure high vibration damping performance by being less affected by the error in the estimated value compared to when the entire speed difference is an estimated value.

[0008] As described above, this configuration makes it possible to realize a vibration control technology that is less susceptible to errors in the estimated values ​​used to calculate the vibration control torque.

[0009] Further features and advantages of the control device will become clear from the following description of the embodiments described with reference to the drawings. [Brief explanation of the drawing]

[0010] [Figure 1] A schematic diagram showing an example of a vehicle controlled by a control device. [Figure 2] A schematic diagram showing an example of a control system for a rotating electric machine. [Figure 3] Control block diagram showing a vibration control unit according to an embodiment. [Figure 4] A diagram showing an example of how drive shaft torque changes over time. [Figure 5] This figure shows another example of the time variation of drive shaft torque. [Modes for carrying out the invention]

[0011] Embodiments of the control device will be described with reference to the drawings. In this specification, the term "rotating electric machine" is used to include motors, generators, and, if necessary, motor-generators that perform both motor and generator functions.

[0012] Control device 1 is a device that controls vehicle V. Control device 1 may be mounted on vehicle V or located outside of vehicle V. Alternatively, control device 1 may be a combination of a device mounted on vehicle V and a device located outside of vehicle V. In this case, some functions of control device 1 are implemented within vehicle V, while the remaining functions are implemented outside of vehicle V.

[0013] As shown in Figure 1 as an example, the vehicle V controlled by the control device 1 is equipped with a rotating electric machine 41 and a power transmission system 44 that transmits the driving force of the rotating electric machine 41 to the wheels W. In other words, the vehicle V is an electric vehicle such as a battery electric vehicle (BEV) equipped with a rotating electric machine 41 as a driving force source for the wheels W. Although Figure 1 illustrates a case where only the rotating electric machine 41 is provided in the vehicle V as a driving force source for the wheels W, the vehicle V may also be equipped with a driving force source other than the rotating electric machine 41 (for example, an internal combustion engine), and the power transmission system 44 may be configured to transmit the driving force of both the rotating electric machine 41 and the other driving force source to the wheels W.

[0014] The power transmission system 44 includes a drive shaft 43, which transmits the driving force of the rotating electric machine 41 to the wheel W connected to the drive shaft 43 via the drive shaft 43. The transmission of driving force between the rotating electric machine 41 and the drive shaft 43 is performed by a power transmission device 42 provided in the power transmission system 44. The power transmission device 42 includes, for example, a transmission shaft and gears. The power transmission device 42 may also include an engagement device such as a clutch or brake. Furthermore, the power transmission device 42 may include a transmission that changes the speed of the input rotation (for example, reduces it) before outputting it. In the example shown in Figure 1, the rotating electric machine 41 is arranged on a different axis from the drive shaft 43, but it is also possible to configure the rotating electric machine 41 to be arranged coaxially with the drive shaft 43.

[0015] The power transmission system 44 is configured to transmit the driving force of the rotating electric machine 41 to one or more wheels W. In the example shown in Figure 1, the power transmission system 44 is configured to transmit the driving force of the rotating electric machine 41 to a pair of wheels W (left and right wheels W). Therefore, although not shown in the figure, the power transmission system 44 (specifically, the power transmission device 42) includes a differential gear mechanism that distributes the rotation transmitted from the rotating electric machine 41 to the pair of wheels W via a pair of drive shafts 43.

[0016] As shown in Figure 2, the rotating electric machine 41 is electrically connected to a DC power source 70, such as a battery or capacitor, via an inverter 60. The rotating electric machine 41 generates driving force by being powered by the electricity stored in the DC power source 70. The rotating electric machine 41 also charges the DC power source 70 by generating electricity using the driving force transmitted to the rotating electric machine 41 (for example, the driving force transmitted from the wheel W). Although not shown in the figure, the rotating electric machine 41 includes a stator and a rotor that is rotatably supported by a non-rotating member (in this case, a case 40) relative to the stator. Coils 50 are wound around the stator. In this embodiment, the rotating electric machine 41 is a rotating electric machine driven by three-phase AC, and three-phase coils 50 are wound around the stator. Figure 2 illustrates a configuration in which the three-phase coils 50 are connected in a star configuration. The rotating electric machine 41 may be a synchronous rotating electric machine such as a permanent magnet type or a wound field type, or it may be an induction rotating electric machine.

[0017] The inverter 60 is configured to convert power between DC power and AC power (in this embodiment, three-phase AC power). The inverter 60 converts the DC power stored in the DC power supply 70 into AC power and supplies it to the rotating electric machine 41. The inverter 60 also converts the AC power generated by the rotating electric machine 41 into DC power and supplies it to the DC power supply 70. The inverter 60 is composed of multiple switching elements. Power transistors such as IGBTs (Insulated Gate Bipolar Transistors), power MOSFETs (Metal Oxide Semiconductor Field Effect Transistors), and HEMTs (High Electron Mobility Transistors) are used as switching elements.

[0018] The control device 1 controls the rotating electric machine 41 via an inverter 60. Specifically, the control device 1 performs switching control on a plurality of switching elements constituting the inverter 60, and causes the inverter 60 to convert electric power between direct-current power and alternating-current power. The control device 1 is configured with a logic circuit such as a microcomputer as a core component. Each function of the control device 1 (for example, the function of the vibration damping control unit 10 described later) is realized through cooperation between hardware such as a microcomputer and software (a program).

[0019] A torque value commanded to the rotating electric machine 41 is defined as a rotating electric machine torque command value T mg (see FIG. 3), the control device 1 controls the rotating electric machine 41 to output a torque corresponding to the rotating electric machine torque command value T mg . The control device 1 performs current feedback control based on, for example, the rotational position of the rotor (for example, the magnetic pole position of the field), the rotational speed of the rotor, and the current flowing through the coils 50 of each phase, thereby controlling the rotating electric machine 41 to output a torque corresponding to the rotating electric machine torque command value T mg . In the example shown in FIG. 2, the rotational position and rotational speed of the rotor are detected by a rotation sensor 51 such as a resolver or an inductive position sensor, and the current flowing through the coils 50 is detected by a current sensor 52.

[0020] Although details will be described later, the control device 1 determines the rotating electric machine torque command value T ref based on a reference torque T mg . The determination (update) of the rotating electric machine torque command value T mg is repeatedly executed for each control cycle. When a vibration damping torque ΔT described later is zero, the reference torque T ref is determined as the rotating electric machine torque command value T mg . The reference torque T ref is a torque (target torque) required for the rotating electric machine 41 from the vehicle V side. The reference torque T ref is determined by the control device 1, or is determined by another device (for example, a vehicle control device that integrally controls the entire vehicle V) and provided to the control device 1.

[0021] Reference Torque T ref This is determined, for example, in response to driving operations by the driver, or in response to commands from systems such as driver assistance systems or autonomous driving systems. The vehicle V has a reference torque T. ref Sensors are provided to detect the information necessary to make a decision. For example, sensors are provided on the vehicle V to detect driving operations by the driver (accelerator operation, brake operation, steering operation, etc.) and sensors to detect the vehicle state (vehicle V's speed, vehicle V's acceleration, etc.).

[0022] The control device 1 includes a vibration control unit 10 (see Figure 3) that outputs a vibration damping torque ΔT to the rotating electric machine 41 to reduce vibrations occurring in the vehicle V. As will be described later, in this embodiment, the vibration control unit 10 outputs a reference torque T ref The torque obtained by subtracting the vibration damping torque ΔT from the torque is the rotating electric machine torque command value T. mg By determining this, the system is configured to output a vibration damping torque ΔT to the rotating electric machine 41.

[0023] Figure 3 shows a control block diagram of the vibration damping control unit 10 according to this embodiment. In Figure 3, the plant P is a model of a vehicle V (specifically, a system from the rotating electric machine 41 to the wheels W via the power transmission system 44). In this embodiment, each function of the vibration damping control unit 10 in Figure 3 is realized in software. Specifically, the memory device of the control device 1 stores a program for realizing each function of the vibration damping control unit 10 in Figure 3, and each function of the vibration damping control unit 10 is realized when the control device 1 (computer) executes this program.

[0024] As shown in Figure 3, the vibration control unit 10 commands the rotating electric machine 41 to set the torque command value T. mg The torque command value acquisition unit 11 acquires the torque command value, and the rotational speed of the rotating electric machine 41 (specifically the rotor) is detected value ω. mg The detection value acquisition unit 12 acquires the value and estimates the wheel speed, which is the rotational speed of the wheel W (specifically, the estimated value ω of the wheel speed).tire It includes a wheel speed estimation unit 13 (which calculates the wheel speed) and a vibration damping torque calculation unit 14 (which calculates the vibration damping torque ΔT).

[0025] The control device 1 (specifically, the vibration control control unit 10) calculates the vibration damping torque ΔT and the rotating electric machine torque command value T based on the calculated vibration damping torque ΔT. mg The determination (update) of the torque command value is repeatedly performed for each control cycle. The torque command value acquisition unit 11 determines the rotating electric machine torque command value T for the current control cycle. mg The detection value acquisition unit 12 acquires the detected value ω of the rotational speed of the rotating electric machine in the current control cycle. mg This is obtained from the detection result of the rotation sensor 51 (see Figure 2). Then, the wheel speed estimation unit 13 uses the detected value ω of the rotating electric machine rotation speed. mg and the torque command value T of the rotating electric machine mg Based on this, the estimated value of the wheel speed ω tire The wheel speed is calculated by the wheel speed estimation unit 13. tire The method for calculating this will be explained later.

[0026] The vibration damping torque calculation unit 14 uses the detected value ω of the rotating electric machine's rotational speed. mg and the estimated value of wheel speed ω tire The torque corresponding to the speed difference when converted to the same position in the power transmission system 44 is calculated as the vibration damping torque ΔT. In Figure 3, the value obtained by converting the rotational speed of the rotating electric machine to the rotational speed at the position of the wheel W (in other words, the position of the drive shaft 43) is shown as the detected value ω of the rotational speed of the rotating electric machine. mg Specifically, the value obtained by dividing the rotational speed of the rotating electric machine by the gear ratio of the power transmission system 44 (specifically, the gear ratio of the power transmission path from the rotating electric machine 41 to the wheel W) is used as the detected value ω of the rotational speed of the rotating electric machine. mg Therefore, the detected value of the rotational speed of the rotating electric machine is ω mg and the estimated value of wheel speed ω tire The difference between these two values ​​represents the speed difference mentioned above. In the example shown in Figure 3, this speed difference is calculated by the second calculation unit 32 of the vibration damping torque calculation unit 14.

[0027] In this embodiment, the vibration damping torque calculation unit 14 is configured to calculate the vibration damping torque ΔT as the torque obtained by multiplying the above-mentioned speed difference by a gain. In the example shown in Figure 3, the calculation of multiplying the above-mentioned speed difference by a gain is performed by the third calculation unit 33 of the vibration damping torque calculation unit 14. The vibration damping control unit 10 then calculates the reference torque T ref The torque obtained by subtracting the vibration damping torque ΔT from the torque is the rotating electric machine torque command value T. mg This is determined as follows. In the example shown in Figure 3, the reference torque T ref The calculation of subtracting the vibration damping torque ΔT from the reference torque T is performed by the fourth calculation unit 34 of the vibration damping control unit 10. ref The torque obtained by subtracting the vibration damping torque ΔT from the torque is the rotating electric machine torque command value T. mg By determining this, a vibration damping torque ΔT can be output to the rotating electric machine 41, thereby reducing vibrations occurring in the vehicle V.

[0028] As described above, vibration control by the vibration control unit 10 is performed using the detected value ω of the rotational speed of the rotating electric machine. mg and the estimated value of wheel speed ω tire This is done by feedback control of the speed difference when converted to the same position in the power transmission system 44. Below, the estimated value of the wheel speed ω by the wheel speed estimation unit 13 according to this embodiment tire The calculation method will be explained.

[0029] The wheel speed estimation unit 13 detects the rotational speed of the rotating electric machine ω mg The first output value ω1 obtained by applying a first filter to the above, and the rotating electric machine torque command value T mg Based on the second output value ω2 obtained by applying a second filtering process to the above, the estimated wheel speed ω tireThe system is configured to calculate the following. In this embodiment, the first filtering process is a filtering process represented by the transfer function of equation (1) below, and the second filtering process is a filtering process represented by the transfer function of equation (2) below. Both the first and second filtering processes are 1-input, 1-output filtering processes. In the example shown in Figure 3, the first filtering process is performed by the first filter 21 provided by the wheel speed estimation unit 13, and the second filtering process is performed by the second filter 22 provided by the wheel speed estimation unit 13.

[0030]

number

[0031]

number

[0032] Here, I is the moment of inertia of the rotating electric machine 41 (specifically, the rotor), c is the viscous friction coefficient of the power transmission system 44, k is the torsional stiffness coefficient of the power transmission system 44, and LPF is a low-pass filter. Also, s is the Laplace operator. The viscous friction coefficient c is expressed in units of, for example, [Nms / rad], and the torsional stiffness coefficient is expressed in units of, for example, [Nm / rad]. For example, the viscous friction coefficient c of the power transmission system 44 can be the viscous friction coefficient of the drive shaft 43 of the power transmission system 44, and the torsional stiffness coefficient k of the power transmission system 44 can be the torsional stiffness coefficient of the drive shaft 43 of the power transmission system 44.

[0033] The wheel speed estimation unit 13 calculates the estimated wheel speed ω by subtracting the second output value ω2 from the first output value ω1, as shown in equation (3) below. tire The calculation is performed as follows. In the example shown in Figure 3, the calculation of subtracting the second output value ω2 from the first output value ω1 is performed by the first calculation unit 31 of the wheel speed estimation unit 13. Thus, the wheel speed estimation unit 13 of this embodiment calculates the detected value ω of the rotational speed of the rotating electric machine as shown in equation (3). mg and the torque command value T of the rotating electric machine mgThe input is the estimated wheel speed ω tire Using a wheel speed observer whose output is ω, we estimate the wheel speed. tire Calculate.

[0034]

number

[0035] The wheel speed observer shown in equation (3) can be derived from the equation of motion on the rotating electric machine 41 side, where there is no disturbance torque applied to the wheel W or moment of inertia of the wheel W, as follows. The equation of motion on the rotating electric machine 41 side can be expressed by the following equation (4), using the moment of inertia I of the rotating electric machine 41, the viscous friction coefficient c of the power transmission system 44, and the torsional stiffness coefficient k of the power transmission system 44. In equation (4), To is the torque of the rotating electric machine 41, and θ mg θ is the rotation angle (phase) of the rotating electric machine 41. tire This represents the rotation angle (phase) of wheel W.

[0036]

number

[0037] When equation (4) is Laplace transformed with respect to rotational speed, equation (5) is obtained, and when equation (5) is converted into a formula for calculating wheel speed, equation (6) is obtained.

[0038]

number

[0039]

number

[0040] The right-hand side of equation (6) is the detected value ω of the rotating electric machine's rotational speed. mg and the torque command value T of the rotating electric machine mgBy substituting the values ​​and multiplying the right-hand side of equation (6) by an LPF (low-pass filter) to make it proper, we obtain equation (3) above. Note that the form of the LPF does not matter as long as it is of order 1 or higher. When using a Butterworth filter as the LPF, for example, a first-order LPF represented by equation (7), a second-order LPF represented by equation (8), or a third-order LPF represented by equation (9) can be used. Here, T is the time constant. It is preferable to select a time constant T that is fast enough so that no delay occurs in the vibration information in the resonant frequency band.

[0041]

number

[0042]

number

[0043]

number

[0044] The wheel speed observer shown in equation (3) does not have external disturbance torque applied to the wheel W (for example, external disturbance torque due to running resistance) or the moment of inertia of the wheel W. Therefore, it is possible to achieve vibration damping that is highly robust to environmental changes such as changes in the contact state of the wheel W, changes in the weight of the vehicle V, and changes in running resistance. In addition, since the first filter 21 and the second filter 22 that constitute the wheel speed observer are both 1-input 1-output filters, the difficulty of adapting and implementing the wheel speed observer can be kept low. Thus, the filter structure of the wheel speed observer in this embodiment does not involve external disturbance elements or the inertia of the wheel W, and is necessary and sufficient based on physical characteristics, making it possible to realize a wheel speed observer with a simple and optimal filter structure.

[0045] Note that the vibration damping torque ΔT calculated by the vibration damping torque calculation unit 14 uses the estimated wheel speed ω, not the detected wheel speed. tireTherefore, the technology of this disclosure can be suitably applied even when a wheel speed sensor for detecting wheel speed is not provided on the vehicle V, or when the performance of the wheel speed sensor provided on the vehicle V is not high enough to be used for vibration damping control.

[0046] Figures 4 and 5 show the drive shaft torque T, which is the torque of the drive shaft 43. ds An example of the time evolution is shown. Here, at time t=0, the reference torque T is the target torque of the rotating electric machine 41. ref This assumes a stepwise increase. Figure 4 assumes a scenario where the wheel W is in contact with the ground, and Figure 5 assumes a scenario where the wheel W is not in contact with the ground (for example, during sudden braking on a wavy road). In Figures 4 and 5, the first curve L1 represents the drive shaft torque T when vibration damping control is not performed. ds This shows the time change of the second curve L2, which represents the drive shaft torque T when vibration damping control is performed as in the comparative example. ds This shows the time change of [the value]. The vibration damping control in the comparative example assumes a scenario where the wheel W is in contact with the ground. The vibration damping control in this comparative example is a control that applies a single-frequency filter (specifically, a two-stage high-pass filter) and feedback compensation to the detection signal of the rotational speed of the rotating electric machine 41. The third curve L3 shows the drive shaft torque T when vibration damping control is performed by the vibration damping control unit 10 of this embodiment. ds This represents the change over time.

[0047] As described above, the vibration damping control of the comparative example assumes a situation where the wheel W is in contact with the ground. Therefore, as shown in Figure 4, in the situation where the wheel W is in contact with the ground, the drive shaft torque T is affected not only in the vibration damping control of this embodiment (third curve L3) but also in the vibration damping control of the comparative example (second curve L2). ds The vibration is reduced. However, in the comparative example's vibration control (second curve L2), overshoot and delay in returning to steady torque occur. In contrast, in the vibration control of this embodiment (third curve L3), the overshoot is improved, and the speed of returning to steady torque is also improved.

[0048] The resonant frequency when wheel W is not in contact with the ground is different from the resonant frequency when wheel W is in contact with the ground. Therefore, as shown in Figure 5, in the case where wheel W is not in contact with the ground, the drive shaft torque T in the comparative example's vibration damping control (second curve L2) is different. ds It is not possible to adequately reduce the vibration. In contrast, in the vibration control of this embodiment (third curve L3), even when the wheel W is not in contact with the ground, the drive shaft torque T ds The vibrations are appropriately reduced.

[0049] Thus, in the vibration control of this embodiment, the drive shaft torque T is controlled regardless of the contact state of the wheel W. ds By reducing vibrations, it is possible to reduce vibrations occurring in the vehicle V. In this case, a single filter structure (in other words, a single adjustment constant) can respond to changes in the contact state of the wheel W. Therefore, the vibration damping control of this embodiment is superior in vibration damping performance to conventional vibration damping control such as the comparative example, regardless of the contact state of the wheel W (in other words, the road surface condition), and is also easy to adapt and implement.

[0050] [Other Embodiments] (1) In the above embodiment, the wheel speed estimation unit 13 detects the rotational speed of the rotating electric machine ω mg The first output value ω1 obtained by applying a first filter to the above, and the rotating electric machine torque command value T mg Based on the second output value ω2 obtained by applying a second filtering process to the above, the estimated wheel speed ω tire A configuration for calculating the rotational speed of the rotating electric machine ω was described as an example. However, this disclosure is not limited to such a configuration, and for example, the wheel speed estimation unit 13 uses a state observer constructed from a state equation to find the detected value ω of the rotational speed of the rotating electric machine. mg and the torque command value T of the rotating electric machine mg Based on this, the estimated wheel speed ω tire It is also possible to configure it to calculate [the result].

[0051] (2) The embodiments disclosed herein are merely illustrative in all respects. Therefore, various modifications can be made as appropriate without departing from the spirit of this disclosure.

[0052] [Summary of this embodiment] The following is a summary of the embodiments of the control device described above.

[0053] The control device (1) controls a vehicle (V) comprising a rotating electric machine (41) and a power transmission system (44) that transmits the driving force of the rotating electric machine (41) to wheels (W), and includes a vibration damping control unit (10) that causes the rotating electric machine (41) to output a vibration damping torque (ΔT) to reduce vibrations occurring in the vehicle (V), and the vibration damping control unit (10) controls the rotating electric machine torque command value (T), which is the value of the torque commanded to the rotating electric machine (41). mg A torque command value acquisition unit (11) acquires the torque command value (ω), and a detected value of the rotational speed of the rotating electric machine (41), which is the rotational speed of the rotating electric machine (ω). mg The system includes a detection value acquisition unit (12) that acquires the rotational speed of the wheel (W), a wheel speed estimation unit (13) that estimates the wheel speed which is the rotational speed of the wheel (W), and a vibration damping torque calculation unit (14) that calculates the vibration damping torque (ΔT), wherein the wheel speed estimation unit (13) acquires the detected value (ω) of the rotational speed of the rotating electric machine. mg ) and the torque command value of the rotating electric machine (T mg Based on the above, the estimated value of the wheel speed (ω tire The vibration damping torque calculation unit (14) calculates the detected value (ω) of the rotational speed of the rotating electric machine. mg ) and the estimated value of the wheel speed (ω tire The torque corresponding to the speed difference when converted to the same position in the power transmission system (44) is calculated as the vibration damping torque (ΔT).

[0054] According to this configuration, the detected value of the rotational speed of the rotating electric machine (ω mg ) and estimated wheel speed (ω tireThe torque corresponding to the speed difference when converted to the same position in the power transmission system (44) with the vehicle (V) is calculated as the vibration damping torque (ΔT) to reduce vibrations occurring in the vehicle (V). Here, the speed difference used in calculating the vibration damping torque (ΔT) is not an estimated value in its entirety; only one of the two values ​​from which the speed difference is calculated (specifically, the wheel speed) is an estimated value, and the other (specifically, the rotational speed of the rotating electric machine) is a detected value. Therefore, the error in the estimated value used in calculating the vibration damping torque (ΔT) can be limited to the error in the wheel speed, and as a result, it is easier to ensure high vibration damping performance by being less affected by the error in the estimated value compared to the case where the entire speed difference is an estimated value.

[0055] As described above, this configuration makes it possible to realize a vibration control technology that is less susceptible to errors in the estimated values ​​used to calculate the vibration control torque (ΔT).

[0056] Here, the wheel speed estimation unit (13) uses the detected value (ω) of the rotational speed of the rotating electric machine. mg The first output value (ω1) obtained by applying a first filter to ) and the rotating electric machine torque command value (T mg Based on the second output value (ω2) obtained by applying a second filtering process to ), the estimated value of the wheel speed (ω tire It is preferable to calculate the following:

[0057] According to this configuration, the estimated value of the wheel speed (ω tire ) can be calculated by performing a first filter and a second filter, both of which are 1 input and 1 output. Therefore, the estimated value of the wheel speed (ω tire The filter structure used in the calculation of ) can be simplified, and the difficulty of fitting and implementing the wheel speed estimation unit (13) can be kept low.

[0058] In the above configuration, the first filtering process is a filtering process represented by the transfer function of equation (1) below, the second filtering process is a filtering process represented by the transfer function of equation (2) below, and the wheel speed estimation unit (13) subtracts the second output value (ω2) from the first output value (ω1) to obtain the estimated wheel speed (ωtire It is preferable to calculate it as follows:

[0059]

number

[0060]

number

[0061] Here, I is the moment of inertia of the rotating electric machine (41), c is the viscous friction coefficient of the power transmission system (44), k is the torsional stiffness coefficient of the power transmission system (44), and LPF is a low-pass filter.

[0062] According to this configuration, an estimated value of the wheel speed (ω) is obtained using a filter structure that does not have external torque applied to the wheel (W) or moment of inertia of the wheel (W). tire This allows for the calculation of (the value of the vibration control system). Therefore, it is easier to achieve vibration control that is highly robust against environmental changes.

[0063] The control device relating to this disclosure only needs to be able to achieve at least one of the effects described above. [Explanation of symbols]

[0064] 1: Control device, 10: Vibration damping control unit, 11: Torque command value acquisition unit, 12: Detected value acquisition unit, 13: Wheel speed estimation unit, 14: Vibration damping torque calculation unit, 41: Rotating electric machine, 44: Power transmission system, T mg : Rotating electric machine torque command value, V: vehicle, W: wheel, ΔT: vibration damping torque, ω1: first output value, ω2: second output value, ω mg : Detected value of rotational speed of rotating electric machine, ω tire Estimated wheel speed

Claims

1. A control device for controlling a vehicle equipped with a rotating electric machine and a power transmission system that transmits the driving force of the rotating electric machine to the wheels, The vehicle is equipped with a vibration damping control unit that outputs a vibration damping torque to the rotating electric machine to reduce vibrations occurring in the vehicle, The vibration control unit described above is A torque command value acquisition unit that acquires a rotating electric machine torque command value, which is the torque value commanded to the rotating electric machine, A detection value acquisition unit that acquires a detected value of the rotational speed of the rotating electric machine, which is the rotational speed of the aforementioned rotating electric machine, A wheel speed estimation unit that estimates the wheel speed, which is the rotational speed of the wheel, A vibration damping torque calculation unit that calculates the aforementioned vibration damping torque, Equipped with, The wheel speed estimation unit calculates an estimated value of the wheel speed based on the detected value of the rotational speed of the rotating electric machine and the torque command value of the rotating electric machine. The vibration damping torque calculation unit is a control device that calculates the vibration damping torque as the torque corresponding to the speed difference between the detected value of the rotational speed of the rotating electric machine and the estimated value of the wheel speed, when converted to the same position in the power transmission system.

2. The control device according to claim 1, wherein the wheel speed estimation unit calculates an estimated value of the wheel speed based on a first output value obtained by applying a first filter process to the detected value of the rotational speed of the rotating electric machine and a second output value obtained by applying a second filter process to the torque command value of the rotating electric machine.

3. The first filtering process is a filtering process represented by the transfer function of equation (1) below, The second filtering process is a filtering process represented by the transfer function of equation (2) below, The wheel speed estimation unit calculates the estimated wheel speed by subtracting the second output value from the first output value. [Math 1] [Math 2] The control device according to claim 2, wherein I is the moment of inertia of the rotating electric machine, c is the viscous friction coefficient of the power transmission system, k is the torsional stiffness coefficient of the power transmission system, and LPF is a low-pass filter.

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