JP6993786B2 - Vehicle and vehicle control method - Google Patents

Description

The present invention relates to a vehicle including a rotary electric machine for driving wheels and a method for controlling the vehicle.

Patent Document 1 aims to provide a drive device for a hybrid vehicle capable of suppressing the occurrence of a resonance phenomenon and improving the space efficiency occupied by the torque limiter mechanism ([0009], abstract).

In order to achieve this object, in Patent Document 1 (summary), in the hybrid vehicle drive device 100A, a torque limiter is provided between the generator 60 and the motor 70 on the power transmission path between the inner peripheral shaft 2a and the generator 60. TL is provided. The torque limiter TL overlaps at least a part of the stator 65 of the generator 60 and / or the stator 75 of the motor 70 in the axial direction.

The torque limiter TL aims to increase the torsional natural frequency of the transmission 90 and suppress the occurrence of a resonance phenomenon due to the coincidence between the torsional natural frequency of the transmission 90 and the engine torque fluctuation frequency (). [0004], [0014], [0049]). It is explained that the suppression of the occurrence of the resonance phenomenon here is to prevent distortion or breakage in the generator shaft 2c or the like ([0004] to [0006], [0046], [0047]).

International Publication No. 2012/053361 Pamphlet

As described above, in Patent Document 1, the torque limiter TL is used to increase the torsional natural frequency of the transmission 90, and the resonance phenomenon is caused by the coincidence between the torsional natural frequency of the transmission 90 and the engine torque fluctuation frequency. It is intended to suppress or the like ([0004], [0014], [0049]).

However, the present inventor has discovered that noise associated with resonance is generated during the operation of a rotary electric machine such as the motor 70 in Patent Document 1 (details will be described later with reference to FIG. 5). Patent Document 1 does not study such noise.

The present invention has been made in consideration of the above-mentioned problems, and an object of the present invention is to provide a vehicle capable of coping with noise caused by a rotary electric machine and a control method thereof.

The vehicle according to the present invention
A rotary electric machine that drives the wheels,
A transmission path for transmitting the power generated by the rotary electric machine to the wheels,
A switching device arranged on the transmission path to switch between the connected state and the non-connected state of the rotary electric machine and the wheel.
It is provided with the switching device and a control circuit for controlling the rotary electric machine.
The control circuit is
A resonance region defined by a first frequency smaller than the resonance frequency of the rotary electric machine and a second frequency larger than the resonance frequency is set.
It is determined whether or not the required driving force of the vehicle is lower than the driving force threshold value and whether or not the rotational speed of the rotary electric machine is within the resonance region.
When the required driving force is lower than the driving force threshold and the rotational speed is within the resonance region, the switching device is switched to the non-connected state and the rotational speed of the rotary electric machine is removed from the resonance region. Execute suppression control ,
The resonance frequency of the rotary electric machine is a resonance frequency peculiar to the stator of the rotary electric machine .

According to the present invention, when the required driving force of the vehicle is lower than the driving force threshold and the rotation speed of the rotary electric machine is within the resonance region, the switching device is switched to the non-connected state and the rotation speed of the rotary electric machine is set to the resonance region. Resonance suppression control to remove from is executed. As a result, the rotating electric machine generates or generates a resonance sound in a state where the required driving force is lower than the driving force threshold value (in other words, a state where the load is relatively low or the vehicle is traveling at a relatively stable vehicle speed). If this is the case, it is possible to suppress the generation of the resonance sound.

In the resonance suppression control, the control circuit may reduce the output of the rotary electric machine or may stop the rotary electric machine. As a result, the power consumption of the rotary electric machine is reduced, and the energy consumption of the entire vehicle can be suppressed.

The vehicle may include an in-vehicle device that is a sound source. The control circuit may determine whether the load of the vehicle-mounted device is equal to or less than the load threshold value or whether the vehicle-mounted device is stopped. Further, in the control circuit, when the load of the in-vehicle device is not equal to or less than the load threshold value, or when the in-vehicle device is not stopped, the required driving force is lower than the driving force threshold value and the rotational speed is the said. The resonance suppression control may be limited even when the state is within the resonance region.

As a result, when the output sound of the vehicle-mounted device, which is a sound source, is small, the rotation speed of the rotary electric machine is changed so as to suppress the resonance sound of the rotary electric machine. Further, when the output sound of the in-vehicle device as a sound source is loud, the resonance sound of the rotary electric machine is not suppressed or weakened. As a result, when the necessity of suppressing the resonance sound is low, it is possible to give priority to the traveling by the rotary electric machine.

Alternatively, the vehicle may include a first vehicle-mounted device and a second vehicle-mounted device that are sound sources. Further, in the control circuit, whether or not the load of the first vehicle-mounted device is equal to or less than the first load threshold value and the load of the second vehicle-mounted device is equal to or less than the second load threshold value, or the first vehicle-mounted device and the said. It may be determined whether or not the second vehicle-mounted device is stopped. Further, in the control circuit, when the load of the first vehicle-mounted device is not equal to or less than the first load threshold value, or when the load of the second vehicle-mounted device is not equal to or less than the second load threshold value, or the first vehicle-mounted device or the said. When the second vehicle-mounted device is not stopped, the resonance suppression control may be limited even when the required driving force is lower than the driving force threshold value and the rotation speed is within the resonance region. ..

As a result, when the output sound of each of the first vehicle-mounted device and the second vehicle-mounted device, which are sound sources, is small, the rotation speed of the rotating electric machine is changed so as to suppress the resonance sound of the rotating electric machine. Further, when the output sound of the first vehicle-mounted device or the second vehicle-mounted device, which is a sound source, is loud, the resonance sound of the rotary electric machine is not suppressed or weakened. As a result, since the output sound from the sound source exists, it is possible to give priority to the traveling by the rotary electric machine when the necessity of suppressing the resonance sound is low.

The vehicle may include an internal combustion engine as an in-vehicle device that is the sound source. As a result, when the output sound of the internal combustion engine is small, the rotation speed of the rotary electric machine is changed so as to suppress the resonance sound of the rotary electric machine. Further, when the output sound of the internal combustion engine is loud, the resonance sound of the rotary electric machine is not suppressed or weakened. As a result, since the output sound of the internal combustion engine is present, it is possible to give priority to the traveling by the rotary electric machine when the necessity of suppressing the resonance sound is low.

The control circuit may monitor whether or not the amount of decrease in vehicle speed exceeds the amount of decrease threshold during the execution of the resonance suppression control. Further, when the decrease amount of the vehicle speed exceeds the decrease amount threshold value, the control circuit switches the switching device from the non-connected state to the connected state and increases the power generated by the rotary electric machine. May be good. As a result, when the vehicle speed decreases due to the decrease or stop of the output of the rotary electric machine, it becomes possible to re-accelerate.

The vehicle control method according to the present invention is
A rotary electric machine that drives the wheels,
A transmission path for transmitting the power generated by the rotary electric machine to the wheels,
A switching device arranged on the transmission path to switch between the connected state and the non-connected state of the rotary electric machine and the wheel.
A vehicle control method including the switching device and a control circuit for controlling the rotary electric machine.
The control circuit is
A resonance region defined by a first frequency smaller than the resonance frequency of the rotary electric machine and a second frequency larger than the resonance frequency is set.
When the predetermined condition is satisfied, it is determined whether or not the rotation speed of the rotary electric machine is within the resonance region.
When the rotation speed is within the resonance region, the switching device is switched to the non-connected state, and resonance suppression control for removing the rotation speed from the resonance region is executed .
The resonance frequency of the rotary electric machine is a resonance frequency peculiar to the stator of the rotary electric machine .

According to the present invention, when the rotation speed of the rotary electric machine is within the resonance region, the resonance suppression control for removing the rotation speed of the rotary electric machine from the resonance frequency region is executed. As a result, when the rotary electric machine is generating or is likely to generate a resonance sound, it is possible to suppress the generation of the resonance sound.

The predetermined condition may include that the rotary electric machine cruise running mode for performing the cruise running by the rotary electric machine is selected. According to the present invention, when the rotary electric machine cruise travel mode is selected and the rotation speed of the rotary electric machine is within the resonance region, resonance suppression control for removing the rotation speed of the rotary electric machine from the resonance frequency region is executed. As a result, when the rotary electric machine is generating or is likely to generate a resonance sound while traveling in the rotary electric machine cruise traveling mode, it is possible to suppress the generation of the resonance sound.

According to the present invention, it is possible to deal with the noise caused by the rotary electric machine.

It is a schematic block diagram of the vehicle which concerns on 1st Embodiment of this invention. It is a figure which shows simply the mechanical connection relationship of the drive system of 1st Embodiment. It is a figure explaining the selection method of the traveling mode used in 1st Embodiment. It is a flowchart of MOT cruise control in 1st Embodiment. It is a figure which shows the change of the sound pressure for each frequency of the vehicle interior noise when the TRC motor of 1st Embodiment is operating at a constant speed (resonance speed). It is a figure which shows the resonance region of 1st Embodiment. It is a figure which shows an example of the relationship between various parameters and the operation of the 1st to 3rd clutches when the MOT cruise control of 1st Embodiment is used. It is a partial flowchart of MOT cruise control in 2nd Embodiment. It is a flowchart which shows the step S31 of FIG. 8 concretely in 2nd Embodiment. It is a schematic block diagram of the vehicle which concerns on 3rd Embodiment of this invention. It is a flowchart which shows the step S31 of FIG. 8 concretely in 3rd Embodiment.

A. First Embodiment <A-1. Configuration of the first embodiment>
[A-1-1. overall structure]
FIG. 1 is a schematic configuration diagram of a vehicle 10 according to the first embodiment of the present invention. FIG. 2 is a diagram simply showing the mechanical connection relationship of the drive system 60 of the first embodiment. The vehicle 10 is a so-called hybrid vehicle. The vehicle 10 includes an engine 20, a first rotary electric machine 22, a second rotary electric machine 24, a first clutch 26, a second clutch 28, a third clutch 30, a torque limiter 32, a wheel 34, and a height. The voltage battery 36, the vehicle speed sensor 38, the SOC sensor 40, the AP operation amount sensor 42, the BP operation amount sensor 44, the rotational speed sensors 46a and 46b, the step-down converter 48, the low voltage battery 50, and the electric supplement. It has a machine 52 and an electronic control device 54 (hereinafter referred to as "ECU 54").

Hereinafter, the engine 20, the first rotary electric machine 22, the second rotary electric machine 24, the first clutch 26, the second clutch 28, and the third clutch 30 are collectively referred to as a drive system 60. Further, the power transmission path connecting the engine 20 and the wheel 34 is referred to as a first transmission path 70. The first transmission path 70 transmits the power Feng generated by the engine 20 to the wheels 34. Further, the power transmission path connecting the first branch point 74 on the engine 20 side of the first clutch 26 and the first rotary electric machine 22 in the first transmission path 70 is referred to as a second transmission path 72. Furthermore, the power transmission path connecting the second branch point 78 on the wheel 34 side of the first clutch 26 and the second rotary electric machine 24 in the first transmission path 70 is referred to as a third transmission path 76.

As shown in FIG. 2, the configuration of the drive system 60 and the like can be the same as that of Patent Document 1 except for the portion peculiar to the first embodiment (second clutch 28 and the like).

Specifically, the drive system 60 includes an engine shaft 200, a motor / generator shaft 202, an output shaft 204, and a differential device 206. The engine 20 is connected to the engine shaft 200 via the crank shaft 210, the drive plate 212 and the damper 214. A first engine shaft gear 220, an ENG clutch 26, and a second engine shaft gear 222 are arranged on the engine shaft 200.

The motor / generator shaft 202 has an inner peripheral shaft 230 and an outer peripheral shaft 232. The inner peripheral shaft 230 is formed with an inner peripheral shaft gear 240 that engages with the first engine shaft gear 220. Therefore, the inner peripheral shaft 230 rotates with the rotation of the engine shaft 200 to drive the generator 22. A GEN clutch 28 and a torque limiter 32 are arranged on the inner peripheral shaft 230. It should be noted that the inner peripheral shaft 230 is connected to the engine shaft 200 regardless of the connection state of the ENG clutch 26.

The outer peripheral shaft 232 of the motor / generator shaft 202 is a hollow member arranged around the inner peripheral shaft 230. An outer peripheral shaft gear 242 that engages with the second engine shaft gear 222 is formed on the outer peripheral shaft 232, and a traveling motor 24 is connected to the outer peripheral shaft gear 232.

The output shaft 204 is arranged parallel to the engine shaft 200 and the motor / generator shaft 202. The output shaft 204 is provided with a first output shaft gear 250 that engages with the outer peripheral shaft gear 242 and a second output shaft gear 252 that engages with the output gear 260 of the differential device 206. A differential shaft 262 is connected to the output gear 260.

Therefore, when the ENG clutch 26 is ON (connected state), so-called parallel traveling is possible in which both the power Feng of the engine 20 and the power Ftrc of the traveling motor 24 are transmitted to the output shaft 204.

Further, when the ENG clutch 26 is OFF (disconnected state), the engine shaft 200 is not connected to the outer peripheral shaft 232 and the output shaft 204. In this case, the power Feng of the engine 20 is transmitted only to the generator 22. Therefore, so-called series running is possible in which the generator 22 is generated by the power Feng of the engine 20 and the electric power obtained by the power generation is supplied to the traveling motor 24.

[A-1-2. Engine 20]
The engine 20 generates a power Feng as a first drive source for traveling of the vehicle 10 and supplies it to the wheel 34 (driving wheel) side. Further, the engine 20 operates the first rotary electric machine 22 by the power Feng to generate electric power. In the following, "ENG" or "eng" is added to the parameters related to the engine 20. Further, in FIG. 1 and the like, the engine 20 is indicated by "ENG".

[A-1-3. 1st rotary electric machine 22]
The first rotary electric machine 22 is a three-phase AC brushless type, and functions as a generator that generates electricity by power Feng from the engine 20. The electric power Pgen generated by the first rotary electric machine 22 is a high voltage battery 36 (hereinafter, also referred to as “battery 36” or “BAT 36”), a second rotary electric machine 24, or electric accessories 52 via a first inverter (not shown). Is supplied to. The first rotary electric machine 22 is an embedded magnet synchronous motor (IPMSM). The first rotary electric machine 22 has a stator 110 and a rotor 112.

Hereinafter, the first rotary electric machine 22 is also referred to as a generator 22. The first rotary electric machine 22 may function as a traveling motor (traction motor) in addition to or instead of the function as a generator. In the following, "GEN" or "gen" is added to the parameters related to the generator 22. Further, in FIG. 1 and the like, the generator 22 is indicated by “GEN”. The generator 22 can be used as a starter motor for the engine 20.

[A-1--4. 2nd rotary electric machine 24]
The second rotary electric machine 24 is a three-phase AC brushless type, and generates a power Ftrc as a second drive source for traveling of the vehicle 10 and supplies it to the wheel 34 (driving wheel) side. That is, the second rotary electric machine 24 functions as a traveling motor driven by one or both of the electric power Pbat from the high voltage battery 36 and the electric power Pgen from the generator 22. Further, the second rotary electric machine 24 regenerates when the vehicle 10 is braked, and supplies the regenerative power Preg to the battery 36 via a second inverter (not shown). The regenerative power Preg may be supplied to the electric auxiliary equipment 52 (hereinafter, also referred to as “auxiliary equipment 52”). Like the generator 22, the second rotary electric machine 24 is an embedded magnet synchronous motor (IPMSM). The second rotary electric machine 24 has a stator 114 and a rotor 116.

Hereinafter, the second rotary electric machine 24 is also referred to as a traveling motor 24 or a TRC motor 24. The second rotary electric machine 24 may function as a generator in addition to or instead of the function as a traveling motor. In the following, "TRC" or "trc" is added to the parameters related to the traveling motor 24. Further, in FIG. 1 and the like, the traveling motor 24 is indicated by "TRC".

[A-1-5. 1st clutch 26, 2nd clutch 28 and 3rd clutch 30]
The first clutch 26 (first switching device) is arranged on the first transmission path 70, and switches between the connected state and the non-connected state of the engine 20 and the wheels 34 based on a command from the ECU 54. Hereinafter, the first clutch 26 is also referred to as an ENG clutch 26 or a COM clutch 26. Here, "COM" means a clutch that is "common" to the engine 20 and the generator 22.

The second clutch 28 (second switching device) is arranged on the second transmission path 72, and switches between the connected state and the non-connected state of the first transmission path 70 and the generator 22 based on a command from the ECU 54. Hereinafter, the second clutch 28 is also referred to as a GEN clutch 28.

The third clutch 30 (third switching device) is arranged on the third transmission path 76, and switches between the connected state and the non-connected state of the first transmission path 70 and the traveling motor 24 based on a command from the ECU 54. Hereinafter, the third clutch 30 is also referred to as a TRC clutch 30.

[A-1-6. Torque limiter 32]
The torque limiter 32 is arranged between the GEN clutch 28 and the first branch point 74 to prevent excessive torque from being transmitted from the generator 22 to the engine 20 or from the engine 20 to the generator 22. The torque limiter 32 may be arranged between the generator 22 and the GEN clutch 28.

[A-1-7. High voltage battery 36]
The high voltage battery 36 is a power storage device (energy storage) that includes a plurality of battery cells and can output a high voltage (several hundred volts), and for example, a lithium ion secondary battery, a nickel hydrogen secondary battery, or the like is used. Can be done. It is also possible to use a power storage device such as a capacitor in place of or in addition to the battery 36.

[A-1-8. Various sensors]
The vehicle speed sensor 38 detects the vehicle speed V [km / h] of the vehicle 10 and transmits it to the ECU 54. The SOC sensor 40 is composed of a current sensor or the like (not shown), detects the remaining amount (SOC: State of Charge) of the battery 36, and transmits it to the ECU 54.

The AP operation amount sensor 42 detects the depression amount (AP operation amount θap) [deg] or [%] from the in-situ position of the accelerator pedal (not shown) and transmits it to the ECU 54. The BP operation amount sensor 44 detects the depression amount (BP operation amount θbp) [deg] or [%] from the in-situ position of the accelerator pedal (not shown) and transmits it to the ECU 54.

The rotation speed sensor 46a detects the rotation speed Ngen [rpm] as the rotation speed per unit time of the generator 22 and transmits it to the ECU 54. The rotation speed sensor 46b detects the rotation speed Ntrc [rpm] as the rotation speed per unit time of the traveling motor 24 and transmits it to the ECU 54.

[A-1-9. Buck converter 48, low voltage battery 50 and electric accessories 52]
The step-down converter 48 steps down the battery voltage Vbat, the generated voltage Vgen, or the regenerative voltage Vreg and supplies them to the electric accessories 52. The battery voltage Vbat is the output voltage of the battery 36, the generated voltage Vgen is the output voltage at the time of power generation of the generator 22, and the regenerated voltage Vreg is the output voltage of the traveling motor 24 at the time of regeneration.

Auxiliary equipment 52 includes an air conditioner 80 and an audio device 82. Further, the auxiliary equipment 52 may include, for example, lights, air conditioning equipment, navigation equipment, and the like.

[A-1-10. ECU 54]
The ECU 54 is a control circuit (or control device) that controls the entire drive system 60, and has an input / output unit 90, a calculation unit 92, and a storage unit 94. The input / output unit 90 inputs / outputs signals to / from each unit of the vehicle 10 via the signal line 96 (communication line). The input / output unit 90 includes an A / D conversion circuit (not shown) that converts the input analog signal into a digital signal.

The arithmetic unit 92 includes a central processing unit (CPU) and operates by executing a program stored in the storage unit 94. Some of the functions executed by the arithmetic unit 92 can also be realized by using a logic IC (Integrated Circuit). The program may be supplied from the outside via a wireless communication device (mobile phone, smartphone, etc.) (not shown). The arithmetic unit 92 may also configure a part of the program with hardware (circuit parts).

As shown in FIG. 1, the calculation unit 92 includes a drive system control unit 100, an engine control unit 102, a generator control unit 104, a traveling motor control unit 106, and a clutch control unit 108.

The drive system control unit 100 controls the drive system of the vehicle 10. The drive system here includes a drive system using the engine 20, a drive system using the traveling motor 24, and a driving system using the engine 20 and the traveling motor 24. At this time, power generation by the generator 22 or regeneration (power generation) by the traveling motor 24 is also controlled. Details will be described later with reference to FIG. 3 and the like.

The engine control unit 102 (hereinafter, also referred to as “ENG control unit 102”) controls the engine 20 based on a command from the drive system control unit 100. The generator control unit 104 (hereinafter, also referred to as “GEN control unit 104”) controls the generator 22 based on a command from the drive system control unit 100. The traveling motor control unit 106 (hereinafter, also referred to as “TRC control unit 106”) controls the traveling motor 24 based on a command from the drive system control unit 100. The clutch control unit 108 controls the first to third clutches 26, 28, 30 based on a command from the drive system control unit 100.

The storage unit 94 stores the program and data used by the arithmetic unit 92, and includes a random access memory (hereinafter referred to as “RAM”). As the RAM, a volatile memory such as a register and a non-volatile memory such as a flash memory can be used. Further, the storage unit 94 may have a read-only memory (hereinafter referred to as “ROM”) in addition to the RAM.

<A-2. Driving mode>
[A-2-1. Overview]
FIG. 3 is a diagram illustrating a method of selecting a traveling mode used in the first embodiment. In the first embodiment, the MOT driving mode, the hybrid driving mode, the ENG driving mode, and the regeneration mode are used. As shown in FIG. 3, the MOT traveling mode, the hybrid traveling mode, and the ENG traveling mode are mainly selected according to the vehicle speed V and the traveling driving force Fd of the vehicle 10.

The traveling driving force Fd may be an actually measured value, an estimated value, or a required value. Further, although the unit of the traveling driving force Fd is set to "Newton (N)" here, it may be set to "Nm" as the torque. When the traveling driving force Fd is set as a required value, the ECU 54 calculates the traveling driving force Fd using the vehicle speed V, the AP operation amount θap, the BP operation amount θbp, and the like.

Further, FIG. 3 shows a traveling resistance line 300. The traveling resistance line 300 indicates a resistance Rt (hereinafter, also referred to as “traveling resistance Rt”) that the vehicle 10 receives when traveling on a specific type of traveling road (for example, a flat asphalt road). When the acceleration due to the traveling driving force Fd of the vehicle 10 is balanced with the deceleration due to the traveling resistance Rt, the vehicle 10 travels at a constant speed. In other words, in order for the vehicle 10 to travel at a constant speed at a specific vehicle speed V, the vehicle 10 may travel on the traveling resistance line 300 with a traveling driving force Fd corresponding to the specific vehicle speed V.

[A-2-2. MOT driving mode]
The MOT traveling mode is a mode in which the traveling motor 24 drives the vehicle 10 mainly by the electric power of the high voltage battery 36. As shown in FIG. 3, the MOT running mode is used during low-speed or medium-speed running, coasting (coasting) running (with charging), and coasting running (without charging). Further, the MOT traveling mode includes control patterns PA11, PA12, and PA13.

In the control pattern PA11 (rotary electric cruise traveling mode), the ENG clutch 26 and the GEN clutch 28 are set to the non-connected state (OFF), and the TRC clutch 30 is set to the connected state (ON). The control pattern PA11 is used, for example, during low-speed / medium-speed traveling (including low-speed cruise and medium-speed cruise).

The control pattern PA12 turns on the ENG clutch 26, the GEN clutch 28, and the TRC clutch 30. The control pattern PA12 is used, for example, during low-speed acceleration. In this case, in addition to the power Ftr of the traveling motor 24 and the power Feng of the engine 20, the power Fgen of the generator 22 is also used to drive the vehicle 10, so that a particularly large vehicle is used. It can generate driving force. The control pattern PA12 may be regarded as belonging to the ENG traveling mode.

The low speed referred to here means, for example, a range larger than 0 km / h and smaller than any one of 10 to 20 km / h. Further, the medium speed means, for example, a range larger than the upper limit of the low speed and smaller than any of 60 to 120 km / h. Further, the high speed described later means, for example, a range larger than the upper limit value of the medium speed and smaller than the upper limit value of the vehicle speed of the vehicle 10.

In the control pattern PA13, the ENG clutch 26, the GEN clutch 28, and the TRC clutch 30 are turned off. This makes it possible to improve the traveling efficiency (or actual fuel consumption) of the vehicle 10 by coasting the vehicle 10 without generating electricity from the generator 22 or the traveling motor 24, for example.

[A-2-3. Hybrid driving mode]
The hybrid driving mode is a mode in which the traveling motor 24 drives the vehicle 10 by using the generated electric power while the generator 22 generates electric power by the power Feng of the engine 20. As shown in FIG. 3, the hybrid driving mode is used during medium-speed acceleration and high-speed rapid acceleration. The hybrid drive mode includes a control pattern PA21 (rotary electric cruise drive mode). In the control pattern PA21, the GEN clutch 28 and the TRC clutch 30 are turned ON while the ENG clutch 26 (COM clutch 26) is turned OFF. As a result, the engine 20 is connected to the generator 22 but is separated from the wheels 34.

[A-2-4. ENG driving mode]
The ENG traveling mode is a mode in which the engine 20 is used as a main drive source for traveling. The ENG travel mode is used, for example, during high-speed acceleration, high-speed cruising, and battery charging. The ENG travel mode includes control patterns PA31 to PA34.

In the control pattern PA31, the GEN clutch 28 is turned off while the ENG clutch 26 and the TRC clutch 30 are turned on. This enables, for example, high-speed acceleration.

In the control pattern PA32, the GEN clutch 28 and the TRC clutch 30 are turned off while the ENG clutch 26 is turned on. This enables, for example, high-speed cruising. The high-speed cruising may relate only to a part of the speed region within the range larger than the upper limit of the medium speed and smaller than the upper limit of the vehicle speed of the vehicle 10. In this specification, the case where the vehicle speed V is constant and the case where the vehicle speed V fluctuates within a predetermined range shall be included in the cruising.

In the control pattern PA33, the TRC clutch 30 is turned off while the ENG clutch 26 and the GEN clutch 28 are turned on. This makes it possible to charge the high voltage battery 36 and the like.

In the control pattern PA34, the GEN clutch 28 is turned on while the ENG clutch 26 and the TRC clutch 30 are turned off. As a result, for example, when the vehicle 10 is coasting, the generator 22 generates electricity by the power Feng of the engine 20, so that the high voltage battery 36 can be charged.

[A-2-5. Regeneration mode]
The regeneration mode is a mode used when the vehicle 10 is decelerated. The regeneration mode includes the control pattern PA41. In the control pattern PA41, the TRC clutch 30 is turned on while the ENG clutch 26 and the GEN clutch 28 are turned off. This makes it possible to charge the high-voltage battery 36 and the like by performing regeneration with the traveling motor 24.

<A-3. Control in the first embodiment>
[A-3-1. Overview]
As described above, in the first embodiment, the ECU 54 switches the driving method of the vehicle 10 according to the vehicle speed V and the traveling driving force Fd of the vehicle 10 (FIG. 3).

[A-3-2. MOT Cruise Control]
(A-3-2-1. Overall flow of MOT cruise control)
Next, MOT cruise control will be described. The MOT cruise control is a control for performing a low-speed cruise or a medium-speed cruise by selectively using the control patterns PA11, P13 or P21 of the MOT traveling mode.

FIG. 4 is a flowchart of MOT cruise control in the first embodiment. In step S11, the ECU 54 determines whether or not the MOT cruise start condition is satisfied. As the MOT cruise start condition, for example, the cruise start switch (not shown) is turned on, and the required value of the traveling driving force Fd of the vehicle 10 (hereinafter referred to as "required driving force Fdreq") is from the driving force threshold THfd. Is also low. The required driving force Fdreq is set based on the AP operation amount θap and the like.

Alternatively, instead of the cruise start switch, the MOT cruise start condition may be that the vehicle is substantially in a cruise state. The term "substantially in a cruise state" as used herein means, for example, that the amount of change in the required driving force Fdreq in the first reference time is less than or equal to a predetermined value and the amount of change in vehicle speed V in the second reference time is less than or equal to a predetermined value. It means that the required driving force Fdreq continues to be equal to or less than a predetermined value in the third reference time. The first to third reference times may be the same or different. Further, in the above determination, any one of the change amount of the required driving force Fdreq, the change amount of the vehicle speed V, and the required driving force Fdreq may be omitted.

If the MOT cruise start condition is not satisfied (S11: FALSE), step S11 is repeated. In this case, the ECU 54 drives the vehicle 10 in another travel mode (for example, ENG travel mode). When the MOT cruise start condition is satisfied (S11: TRUE), the process proceeds to step S12.

In step S12, the ECU 54 turns on the TRC clutch 30, turns off the ENG clutch 26, and turns on the TRC motor 24 (control pattern PA11 or P21). As a result, the vehicle 10 is driven only by the TRC motor 24.

At this time, the operations of the engine 20 and the generator 22 can be set according to the SOC of the battery 36. For example, when the SOC is equal to or higher than the SOC threshold THsoc, the engine 20 and the generator 22 are stopped. At this time, the GEN clutch 28 is turned off (control pattern PA11). When the SOC is less than the SOC threshold THsoc, the driving force of the engine 20 causes the generator 22 to generate electricity to charge the battery 36. At this time, the GEN clutch 28 is turned on (control pattern P21).

In step S13, the ECU 54 determines whether or not the vehicle speed V is outside the target range Rvtar. Specifically, the ECU 54 sets the target cruise vehicle speed Vtarc. Then, the ECU 54 determines whether the vehicle speed V is lower than Vtarc-α or higher than Vtarc + α. The range of Vtar-α or more and Vtar + α or less is the target range Rvtar. Here, the same value α is added or subtracted centering on the target cruise vehicle speed Vtarc, but the value to be added and the value to be subtracted may be different. When the vehicle speed V is outside the target range Rvtar (S13: TRUE), the process proceeds to step S14.

In step S14, the ECU 54 determines whether or not the vehicle speed V is lower than Vtarc-α. In other words, the ECU 54 determines whether or not the vehicle speed V is lower than the target range Rvtar. When the vehicle speed V is lower than Vtarc-α (S14: TRUE), in step S15, the ECU 54 increases the output of the TRC motor 24 to accelerate the vehicle 10. When the vehicle speed V does not fall below Vtarc-α (S14: FALSE), it can be said that the vehicle speed V exceeds Vtarc + α. In that case, in step S16, the ECU 54 reduces the output of the TRC motor 24 to decelerate the vehicle 10.

Returning to step S13, when the vehicle speed V is not outside the target range Rvtar (S13: FALSE), the vehicle speed V is within the target range Rvtar (Vtarc-α ≦ V ≦ Vtarc + α). In that case, the process proceeds to step S17.

In step S17, the ECU 54 determines whether or not the rotational speed Ntrc of the TRC motor 24 is outside the resonance region Rr. Specifically, in the ECU 54, whether the rotation speed Ntrc is lower than the first rotation speed threshold THntrc1 (hereinafter, also referred to as “threshold THwrc1”) (Ntrc <THtrc1) or the second rotation speed threshold THtrc2 (hereinafter, also referred to as “threshold THntrc2”). It is determined whether or not it exceeds (Ntrc> THntrc2). The range of the threshold value THntrc1 or more and the threshold value THntrc2 or less is the resonance region Rr. The resonance region Rr will be described later with reference to FIGS. 5 and 6.

When the rotation speed Ntrc is outside the resonance region Rr (S17: TRUE), in step S18, the ECU 54 maintains the current output (power Ftrc) of the TRC motor 24. When the rotation speed Ntrc is not outside the resonance region Rr (S17: FALSE), the rotation speed Ntrc is in the resonance region Rr (THntrc1 ≦ Ntrc ≦ THntrc2). In that case, the process proceeds to step S19.

In step S19, the ECU 54 executes coasting running (inertial running). Specifically, the ECU 54 turns off the TRC clutch 30 and the TRC motor 24 in addition to turning off the ENG clutch 26 (control pattern PA13). This makes it possible to improve the energy efficiency of the entire vehicle 10 by executing the coasting run during the cruise run. Since the coasting run in step S19 has an aspect of suppressing the resonance of the TRC motor 24 by changing the rotational speed Ntrc of the TRC motor 24, the control for executing the coasting run is also referred to as resonance suppression control below.

In step S20, the ECU 54 determines whether or not the decrease amount ΔV of the vehicle speed V has increased. The decrease amount ΔV (hereinafter, also referred to as “vehicle speed decrease amount ΔV”) means the decrease amount [km / h] of the vehicle speed V after the coasting running (S19) is started. Therefore, the ECU 54 stores the vehicle speed V at the time when step S19 is started, and calculates the difference from the vehicle speed V at the time of step S20 as the reduction amount ΔV. Whether or not the decrease amount ΔV is large is determined by whether or not the decrease amount ΔV is equal to or greater than the decrease amount threshold THΔv. When the decrease amount ΔV is not large (S20: FALSE), step S20 is repeated (as a result, the state of step S19 is maintained).

After step S15, S16 or S18, or when the amount of decrease ΔV is large (S20: TRUE), the process proceeds to step S21. In step S21, the ECU 54 determines whether or not the MOT cruise end condition is satisfied. As the MOT cruise end condition, for example, the driver depresses the accelerator pedal (specifically, the AP operation amount θap becomes equal to or more than the operation amount threshold THθap, or the time derivative value of the AP operation amount θap [deg / sec] is equal to or greater than the operation speed threshold value THΔθap). Alternatively, the MOT cruise end condition may be that the cruise start button (not shown) is turned off.

If the MOT cruise end condition is not satisfied (S21: FALSE), the process returns to step S12. When the MOT cruise end condition is satisfied (S21: TRUE), the current MOT cruise control is ended, and the process returns to step S11.

(A-3-2-2. Resonance speed Nr of TRC motor 24)
FIG. 5 is a diagram showing changes in the sound pressure P for each frequency fs of vehicle interior noise when the TRC motor 24 of the first embodiment is operating at a constant speed (resonance speed Nr). The horizontal axis of FIG. 5 is time [sec], and the vertical axis is the frequency fs of vehicle interior noise. The sound pressure P is shown for each frequency fs of the noise in the vehicle interior, and the sound pressure P is expressed by the gradation according to the value. In the example of FIG. 5, an example of the sound pressure P when the vehicle speed V is constant at V1 and the rotation speed Ntrc is constant at the resonance speed Nr during MOT cruise running is shown. Vehicle interior noise is detected by a microphone (not shown) at a specific point in the vehicle interior of the vehicle 10 (for example, above the driver's seat).

As can be understood from FIG. 5, in the vicinity of the frequency fs of the vehicle interior noise being a specific value (stator annulus 0th resonance generation frequency fsr0), the sound pressure P is larger than that of the surroundings. As confirmed by the present inventor, it was found that this is noise due to the resonance of the TRC motor 24. More specifically, this noise may be caused by the resonance of the annular stator 114 (FIG. 2) of the TRC motor 24 during the operation of the TRC motor 24 (annular 0th-order eigenmode). all right. In other words, when the harmonics of the rotation speed of the rotor 116 of the TRC motor 24 include a frequency corresponding to the stator-specific resonance frequency (stator ring 0th-order resonance generation frequency fsr0) (that is, rotation of the TRC motor 24). It was found that the velocity Ntrc occurs at or around the resonant velocity Nr). This noise can be offensive to the occupants. Therefore, in the first embodiment, measures are taken against the noise of the TRC motor 24.

(A-3-2-3. Resonance region Rr of TRC motor 24)
FIG. 6 is a diagram showing a resonance region Rr of the first embodiment. The horizontal axis of FIG. 6 is the rotation speed Ntrc of the TRC motor 24, and the vertical axis is the output torque Ttrc (TRC output) of the TRC motor 24. As shown in FIG. 6, in the first embodiment, the resonance region Rr is set around the resonance speed Nr. Specifically, Nr-β is set to the first rotation speed threshold THntrc1 (first frequency), and Nr + γ is set to the second rotation speed threshold THntrc2 (second frequency). Therefore, the resonance region Rr is defined by the first rotation speed threshold THntrc1 and the second rotation speed threshold THntrc2. β and γ are positive integers, and β = γ in the first embodiment. However, β ≠ γ may be set.

(A-3-2-4. Example of coasting running)
FIG. 7 is a diagram showing an example of the relationship between various parameters and the operations of the first to third clutches 26, 28, and 30 when the MOT cruise control of the first embodiment is used. In FIG. 7, the vehicle speed V and the output (TRC output) of the traveling motor 24 are shown as parameters.

In FIG. 7, the vehicle 10 is accelerated by the TRC motor 24 from the time points t11 to t12 (S15 in FIG. 4). During the time points t12 to t13, the TRC motor 24 runs at a constant speed (S18). Then, the coasting run is performed between the time points t13 and t14 (S19). Since the decrease amount ΔV of the vehicle speed V becomes equal to or more than the decrease amount threshold THΔv at the time point t14 (S20: TRUE), acceleration is performed again at the time points t14 to t15 (S15).

The same applies after the time point t15. That is, the coasting run is executed between the time points t15 to t16 and t17 to t18. Further, acceleration is performed between the time points t16 to t17 and t18 to t19.

<A-4. Effect of the first embodiment>
According to the first embodiment, the required driving force Fdreq of the vehicle 10 is lower than the driving force threshold THfd (S11: TRUE in FIG. 4), and the rotation speed Ntrc of the TRC motor 24 (rotary electric machine) is in the resonance region Rr. In the case (S17: FALSE), the TRC clutch 30 (switching device) is switched off (disconnected state) (S19), and the TRC motor 24 is turned off to remove the rotational speed Ntrc from the resonance region Rr. (Resonance suppression control) is executed (S19). As a result, the TRC motor 24 generates a resonance sound in a state where the required driving force Fdreq is lower than the driving force threshold THfd (in other words, a state where the load is relatively low or the vehicle is traveling at a relatively stable vehicle speed). If it is or is likely to occur, it is possible to suppress the generation of the resonance sound.

During the coasting run (resonance suppression control) of the first embodiment, the ECU 54 (control circuit) reduces the output of the TRC motor 24 (rotary electric machine) or stops the TRC motor 24 (S19 in FIG. 4). As a result, the power consumption of the TRC motor 24 is reduced, and the energy consumption of the entire vehicle 10 can be suppressed.

In the first embodiment, the ECU 54 (control circuit) monitors whether or not the decrease amount ΔV of the vehicle speed V exceeds the decrease amount threshold THΔv during the coasting running (resonance suppression control) (S20 in FIG. 4). ). Further, when the vehicle speed decrease amount ΔV exceeds the decrease amount threshold value THΔv (S20: TRUE), the ECU 54 switches the TRC clutch 30 (switching device) from OFF (non-connected state) to ON (connected state) (S12). , The power Threshold generated by the TRC motor 24 (rotary electric machine) is increased (S15). As a result, when the vehicle speed V decreases due to the decrease or stop of the output of the TRC motor 24, it becomes possible to re-accelerate.

B. 2nd Embodiment <B-1. Overall configuration (difference from the first embodiment)>
The hardware configuration of the second embodiment is the same as that of the first embodiment, and the configuration of FIG. 1 can be applied as it is. In the following, similar components are designated by the same reference numerals and detailed description thereof will be omitted. In the second embodiment, a part of the control by the ECU 54 (or the program executed by the ECU 54) is different from the first embodiment.

<B-2. Control in the second embodiment>
[B-2-1. Outline (difference from the first embodiment)]
The MOT cruise control of the second embodiment is basically the same as the MOT cruise control of the first embodiment (FIG. 4). The MOT cruise control of the second embodiment is different from the MOT cruise control of the first embodiment in that it has additional processing related to the coasting run (S19).

[B-2-2. MOT Cruise Control]
(B-2-2-1. Overall flow of MOT cruise control)
FIG. 8 is a partial flowchart of MOT cruise control in the second embodiment. Steps S17, S18, S19, and S20 of FIG. 8 are the same as steps S17, S18, S19, and S20 of FIG. In FIG. 8, step S31 is added as compared with FIG.

In step S31, the ECU 54 determines whether or not the output of any of the sound sources in the vehicle 10 is low. The sound source here includes an engine 20, an air conditioner 80, and an audio device 82 (FIG. 1). If the output of any of the sound sources is not low (S31: FALSE), the process proceeds to step S18, and the ECU 54 maintains the output of the TRC motor 24. If the output of any of the sound sources is low (S31: TRUE), the process proceeds to step S19, and the coasting run is executed.

(B-2-2-2. Specific contents of step S31 in FIG. 8)
FIG. 9 is a flowchart specifically showing step S31 of FIG. 8 in the second embodiment. In step S51, the ECU 54 determines whether or not the engine 20 is in low load operation. Specifically, it is determined whether or not the ENG torque Teng (or the power Feng of the engine 20) is equal to or less than the torque threshold THteng. When the engine 20 is in low load operation (S51: TRUE), the process proceeds to step S52.

In step S52, the ECU 54 determines whether or not the air conditioner 80 is in low load operation. Specifically, it is determined whether or not the supply current Iac to the air conditioner 80 is equal to or less than the current threshold value Thiac. When the air conditioner 80 is in low load operation (S52: TRUE), the process proceeds to step S53.

In step S53, the ECU 54 determines whether or not the volume Da of the audio device 82 is low. Specifically, it is determined whether or not the value of the volume switch (not shown) of the audio device 82 is equal to or less than the volume threshold value THav. When the audio device 82 is in low load operation (S53: TRUE), the process proceeds to step S19 (FIG. 8). On the other hand, if any of steps S51 to S53 is false (FALSE), the process proceeds to step S18 (FIG. 8).

<B-3. Effect of the second embodiment>
According to the second embodiment as described above, the following effects can be obtained in addition to or in place of the effects of the first embodiment.

According to the second embodiment, the vehicle 10 includes an engine 20 (first vehicle-mounted device), an air conditioner 80 (second vehicle-mounted device), and an audio device 82 (third vehicle-mounted device), which are sound sources (FIG. 1). .. In the ECU 54 (control circuit), whether or not the torque Teng (load) of the engine 20 is equal to or less than the torque threshold THteng (first load threshold) (S51 in FIG. 9), and the supply current Iac (load) of the air conditioner 80 are determined. It is determined whether or not the current threshold value is Thiac (second load threshold value) or less (S52) and whether or not the volume Da of the audio device 82 is low (S53). Further, the ECU 54 is used when the engine torque Teng is not equal to or less than the torque threshold THteng (S51: FALSE in FIG. 9), or when the supply current Iac of the air conditioner 80 is not equal to or less than the current threshold THiac (S52: FALSE), or the audio device 82. When the volume Da of is not small (S53: FALSE), the required driving force Fdreq is lower than the driving force threshold value THfd (S11: TRUE in FIG. 4), and the rotation speed Ntrc of the TRC motor 24 is within the resonance region Rr (S53: TRUE). Even in S17: FALSE), coasting running (or resonance suppression control) is restricted (or not performed).

As a result, when the output sounds of the engine 20, the air conditioner 80, and the audio device 82, which are sound sources, are small, the rotation speed Ntrc of the TRC motor 24 is changed so as to suppress the resonance sound of the TRC motor 24. Further, when the output sound of any of the engine 20, the air conditioner 80, or the audio device 82, which is a sound source, is loud, the resonance sound of the TRC motor 24 is not suppressed or weakened. As a result, since the output sound from any of these sound sources exists, it is possible to give priority to the traveling by the TRC motor 24 when the necessity of suppressing the resonance sound is low.

In the second embodiment, the vehicle 10 includes an engine 20 as a sound source (S51 in FIGS. 1 and 9). As a result, when the output sound of the engine 20 is small, the rotation speed Ntrc of the TRC motor 24 is changed so as to suppress the resonance sound of the TRC motor 24. Further, when the output sound of the engine 20 is loud, the resonance sound of the TRC motor 24 is not suppressed or weakened. As a result, since the output sound of the engine 20 is present, it is possible to give priority to the traveling by the TRC motor 24 when the necessity of suppressing the resonance sound is low.

C. Third Embodiment <C-1. Configuration of the third embodiment>
[C-1-1. Overall configuration (differences from the first and second embodiments)]
FIG. 10 is a schematic configuration diagram of the vehicle 10A according to the third embodiment of the present invention. The same reference numerals are given to the same components as those of the first and second embodiments, and detailed description thereof will be omitted.

The vehicle 10 of the first and second embodiments had two rotary electric machines 22 and 24 (generator 22 and traveling motor 24) (FIG. 1). On the other hand, the vehicle 10A of the third embodiment has only one rotary electric machine 120.

Similar to the first and second embodiments, the third embodiment also has three clutches (first to third clutches 130, 132, 134). However, since the third embodiment has only one rotary electric machine 120, the arrangement of the first to third clutches 130, 132, 134 is such that the first to third clutches 26, 28, of the first and second embodiments are arranged. Different from 30.

Hereinafter, the engine 20, the rotary electric machine 120, the first clutch 130, the second clutch 132, and the third clutch 134 are collectively referred to as a drive system 60a. Further, the power transmission path connecting the engine 20 and the wheel 34 is referred to as a first transmission path 140. Further, the power transmission path connecting the first transmission path 140 and the rotary electric machine 120 is referred to as a second transmission path 142. The branch point from the first transmission path 140 to the second transmission path 142 is called a branch point 144.

The rotation speed sensor 46 in FIG. 10 detects the rotation speed Nmg [rpm] as the rotation speed per unit time of the rotary electric machine 120 and transmits it to the ECU 54.

[C-1-2. Rotating machine 120]
The rotary electric machine 120 is a three-phase AC brushless type and has a function as a traveling motor and a generator. That is, the rotary electric machine 120 as a traveling motor generates power Fmg as a second driving source for traveling of the vehicle 10A and supplies it to the wheel 34 (driving wheel) side. Further, the rotary electric machine 120 regenerates when the vehicle 10A is braked, and supplies the regenerative power Preg to the battery 36 or the electric auxiliary machines 52 via an inverter (not shown).

Further, the rotary electric machine 120 as a generator generates electricity by the power Feng from the engine 20, and is supplied to the battery 36 or the electric auxiliary machines 52 via an inverter (not shown).

Hereinafter, the rotary electric machine 120 is also referred to as a motor generator 120. Add "MG" or "mg" to the parameters associated with the motor generator 120. Further, in FIG. 10 and the like, the motor generator 120 is indicated by “MG”. The motor generator 120 can be used as a starter motor for the engine 20. Like the first rotary electric machine 22 and the second rotary electric machine 24, the rotary electric machine 120 is an embedded magnet synchronous motor (IPMSM) and has a stator and a rotor.

[C-1-3. 1st clutch 130, 2nd clutch 132 and 3rd clutch 134]
The first clutch 130 (first switching device) is arranged between the wheel 34 and the branch point 144 in the first transmission path 140. The first clutch 130 switches between the connected state and the non-connected state of the combination of the engine 20 and the motor generator 120 and the wheels 34 based on the command from the ECU 54. That is, the first clutch 130 is in the same position as the first clutch 26 of the first embodiment. Hereinafter, the first clutch 130 is also referred to as a COM clutch 130. Here, "COM" means a clutch that is "common" to the engine 20 and the motor generator 120.

The second clutch 132 (second switching device) is arranged on the second transmission path 142, and switches between the connected state and the non-connected state of the first transmission path 140 and the motor generator 120 based on a command from the ECU 54. .. Hereinafter, the second clutch 132 is also referred to as an MG clutch 132.

The third clutch 134 (third switching device) is arranged between the engine 20 and the branch point 144 in the first transmission path 140, and is connected and disconnected between the engine 20 and the wheel 34 (or the branch point 144). The state is switched to the ECU 54 based on a command. Hereinafter, the third clutch 134 is also referred to as an ENG clutch 134.

<C-2. Driving mode>
As described above, in the third embodiment, only one rotary electric machine 120 is used. Therefore, in the third embodiment, the MOT traveling mode and the ENG traveling mode are mainly used. Similar to the first and second embodiments (FIG. 3), in the third embodiment as well, the selection of the traveling mode is mainly performed based on the vehicle speed V and the traveling driving force Fd of the vehicle 10A.

<C-3. Control in the third embodiment>
[C-3-1. Overview]
In the third embodiment, the MOT traveling mode, the ENG traveling mode, and the regeneration mode are used. Similar to the first and second embodiments, in the third embodiment, the MOT traveling mode and the ENG traveling mode are mainly selected according to the vehicle speed V and the traveling driving force Fd of the vehicle 10A.

[C-3-2. MOT Cruise Control]
Next, the MOT cruise control of the third embodiment will be described. The MOT cruise control of the third embodiment is a control for performing a low-speed cruise or a medium-speed cruise using the motor generator 120.

The MOT cruise control of the third embodiment is basically the same as the MOT cruise control of the second embodiment. That is, a part of the flowchart of FIG. 4 is replaced with the flowchart of FIG. However, in FIG. 4 or FIG. 8, the process relating to the TRC motor 24 is the process relating to the motor generator 120 in the third embodiment.

For example, with respect to step S12 of FIG. 4, in the third embodiment, the COM clutch 130 and the MG clutch 132 are turned ON (connected state), and the ENG clutch 134 is turned OFF (non-connected state). Regarding step S17 of FIG. 4 or FIG. 8, in the third embodiment, the rotation speed Nmg of the motor generator 120 is used instead of the rotation speed Ntrc of the TRC motor 24. Regarding step S19 in FIG. 4, in the third embodiment, the COM clutch 130, the MG clutch 132, and the ENG clutch 134 are turned off (disconnected state), and the motor generator 120 is turned off. In the second embodiment, the details of step S31 in FIG. 8 are shown in FIG. On the other hand, in the third embodiment, the details of step S31 in FIG. 8 are shown in FIG.

FIG. 11 is a flowchart specifically showing step S31 of FIG. 8 in the third embodiment. In step S61, the ECU 54 determines whether or not the engine 20 is off (stopped). Specifically, it is determined whether or not the combustion in the engine 20 is stopped. Alternatively, it may be determined based on whether or not the rotation speed Neng of the engine 20 is zero. If the engine 20 is off (S61: TRUE), the process proceeds to step S62.

In step S62, the ECU 54 determines whether or not the air conditioner 80 is off (stopped). Specifically, it is determined whether or not the on / off switch (not shown) of the air conditioner 80 is in the off position. If the air conditioner 80 is off (S62: TRUE), the process proceeds to step S63.

In step S63, the ECU 54 determines whether or not the audio device 82 is off (stopped). Specifically, it is determined whether or not the on / off switch (not shown) of the audio device 82 is in the off position. If the audio device 82 is off (S63: TRUE), the process proceeds to step S19 (FIG. 8). On the other hand, if any of steps S61 to S63 is false (FALSE), the process proceeds to step S18 (FIG. 8).

<C-4. Effect of the third embodiment>
According to the third embodiment as described above, the following effects can be obtained in addition to or in place of the effects of the first and second embodiments.

According to the third embodiment, the required driving force Fdreq of the vehicle 10A is lower than the driving force threshold THfd (S11: TRUE in FIG. 4), and the rotation speed Nmg of the motor generator 120 (rotary electric machine) is within the resonance region Rr. In some cases, the MG clutch 132 (switching device) is switched off (disconnected state), and the motor generator 120 is turned off to execute coasting running (resonance suppression control) that removes the rotational speed Nmg from the resonance region Rr. (S19). As a result, the motor generator 120 generates a resonance sound in a state where the required driving force Fdreq is lower than the driving force threshold THfd (in other words, a state where the load is relatively low or the vehicle is traveling at a relatively stable vehicle speed). If it is or is likely to occur, it is possible to suppress the generation of the resonance sound.

In the third embodiment, the vehicle 10A includes an engine 20 (first vehicle-mounted device), an air conditioner 80 (second vehicle-mounted device), and an audio device 82 (third vehicle-mounted device), which are sound sources (FIG. 10). The ECU 54 (control circuit) determines whether or not the engine 20, the air conditioner 80, and the audio device 82 are off (S61 to S63). Further, when any of the engine 20, the air conditioner 80, and the audio device 82 is not turned off (S61: FALSE, S62: FALSE or S63: FALSE), the required driving force Fdreq of the ECU 54 is lower than the driving force threshold THfd (S61: FALSE, S62: FALSE or S63: FALSE). Even in the state of S11: TRUE in FIG. 4 and the rotational speed Nmg of the motor generator 120 within the resonance region Rr (S17: FALSE in FIG. 8), coasting running (or resonance suppression control) is restricted.

As a result, when the output sounds of the engine 20, the air conditioner 80, and the audio device 82, which are sound sources, are small, the rotation speed Ntrc of the TRC motor 24 is changed so as to suppress the resonance sound of the TRC motor 24. Further, when the output sound of any of the engine 20, the air conditioner 80, or the audio device 82, which is a sound source, is loud, the resonance sound of the TRC motor 24 is not suppressed or weakened. As a result, since the output sound from any of these sound sources exists, it is possible to give priority to the traveling by the TRC motor 24 when the necessity of suppressing the resonance sound is low.

D. Modifications The present invention is not limited to the above embodiments, and it goes without saying that various configurations can be adopted based on the contents described in the present specification. For example, the following configuration can be adopted.

<D-1. Applicable target>
The vehicle 10 of the first and second embodiments has an engine 20, a generator 22 and a traveling motor 24 (FIG. 1), and the vehicle 10A of the third embodiment has an engine 20 and a motor generator 120 (FIG. 1). 10). However, for example, when the rotation speed Ntrc or Nmg is in the resonance region Rr, the rotation speed Ntrc or Nmg is not limited to this from the viewpoint of removing the rotation speed Ntrc or Nmg from the resonance region Rr. For example, the vehicle 10 can be configured to have an engine 20 and three rotary electric machines.

<D-2. Rotating machine ＞
The first rotary electric machine 22 and the second rotary electric machine 24 of the first and second embodiments and the rotary electric machine 120 of the third embodiment are all three-phase AC brushless type. However, for example, when the rotation speed Ntrc or Nmg is in the resonance region Rr, the rotation speed Ntrc or Nmg is not limited to this from the viewpoint of removing the rotation speed Ntrc or Nmg from the resonance region Rr. The first rotary electric machine 22, the second rotary electric machine 24, and the rotary electric machine 120 of the third embodiment may be a direct current type or a brush type.

The first rotary electric machine 22 and the second rotary electric machine 24 of the first and second embodiments and the rotary electric machine 120 of the third embodiment are all embedded magnet synchronous motors (IPMSM). However, for example, when the rotation speed Ntrc or Nmg is in the resonance region Rr, the rotation speed Ntrc or Nmg is not limited to this from the viewpoint of removing the rotation speed Ntrc or Nmg from the resonance region Rr. The first rotary electric machine 22, the second rotary electric machine 24, and the rotary electric machine 120 of the third embodiment may be other types of rotary electric machines.

<D-3. Clutch>
In the third embodiment, the first to third clutches 130, 132, and 134 are provided (FIG. 10). However, the present invention is not limited to this, for example, from the viewpoint of disconnecting the motor generator 120 when traveling by the engine 20. For example, it is possible to omit the third clutch 134.

In the first and second embodiments, the traveling motor 24 and the third clutch 30 are connected to the second branch point 78 between the ENG clutch 26 and the wheel 34 (FIGS. 1 and 2). However, the present invention is not limited to this, for example, from the viewpoint of disconnecting the generator 22 when traveling by the engine 20. For example, the second branch point 78 may be set on the engine 20 side of the ENG clutch 26.

<D-4. Torque limiter 32>
In the first and second embodiments, the torque limiter 32 is provided (FIGS. 1 and 2). However, the present invention is not limited to this, for example, from the viewpoint of disconnecting the rotary electric machine when traveling by the engine 20. For example, the torque limiter 32 can be omitted. Alternatively, in the first and second embodiments, another torque limiter may be provided between the traveling motor 24 and the second branch point 78. The same applies to the third embodiment.

<D-5. MOT Cruise Control>
In the first embodiment, when the rotational speed Ntrc of the TRC motor 24 is within the resonance region Rr (S17: FALSE in FIG. 4), the TRC clutch 30 and the TRC motor 24 are turned off (S19). However, for example, when the rotation speed Ntrc is in the resonance region Rr, the rotation speed Ntrc is not limited to this from the viewpoint of removing the rotation speed Ntrc from the resonance region Rr. For example, the rotation speed Ntrc may be removed from the resonance region Rr by reducing or increasing the output of the TRC motor 24 without turning it off. In that case, the target cruise vehicle speed Vtarc may be increased or decreased.

In the MOT cruise control (FIG. 4) of the first embodiment, the resonance suppression control can be executed only when the vehicle speed V is within the target range Rvtar (S13: FALSE). However, for example, when the rotation speed Ntrc is in the resonance region Rr, the step S13 may be omitted from the viewpoint of removing the rotation speed Ntrc from the resonance region Rr. In that case, the output of the TRC motor 24 may be increased or decreased so as to reduce the time during which the rotational speed Ntrc is in the resonance region Rr. The same applies to the second and third embodiments.

In the MOT cruise control (FIG. 4) of the first embodiment, it was determined whether or not to end the coasting running (resonance suppression control) based on the vehicle speed decrease amount ΔV (S20). However, the present invention is not limited to this, for example, from the viewpoint of determining the timing at which the resonance suppression control is terminated. For example, the timing for ending the resonance suppression control may be determined based on the time from the start of the coasting run (resonance suppression control).

In the second embodiment, the engine 20, the air conditioner 80, and the audio device 82 are mentioned as the sound sources targeted in step S31 of FIG. 8 (FIG. 9). However, for example, from the viewpoint of determining whether or not the resonance sound of the TRC motor 24 is conspicuous, the sound source to be targeted is not limited to this. For example, one or two of the engine 20, the air conditioner 80, and the audio device 82 may be omitted. Alternatively, other sound sources (for example, a state in which the window is open) may be targeted. The same applies to the third embodiment.

<D-6. Others>
In the first embodiment, MOT cruise control was performed according to the flow shown in FIG. However, for example, when the effect of the present invention can be obtained, the content of the flow (order of each step) is not limited to this. For example, the positions of steps S13 to S16 and steps S17 to S20 can be exchanged. The same applies to the second and third embodiments.

In the second embodiment, when the required driving force Fdreq is lower than the driving force threshold THfd (S11: TRUE in FIG. 4) and the rotation speed Ntrc of the TRC motor 24 is within the resonance region Rr (S17: FALSE), any The sound source also determined whether or not the output sound was low (S31 in FIG. 8). Alternatively, it is possible to perform one or both of S11 and S17 in FIG. 4 after performing S31 in FIG. The same applies to the third embodiment.

In each of the above embodiments, there are cases where the equal sign is included and cases where the equal sign is not included in the comparison of numerical values (S13 and the like in FIG. 4). However, for example, unless there is a special meaning to include or remove the equal sign (in other words, when the effect of the present invention can be obtained), it is optional to include or not include the equal sign in the numerical comparison. Can be set to.

In that sense, for example, it is determined whether or not the vehicle speed V in step S13 of FIG. 4 is lower than the target cruise vehicle speed Vtarc-α (V <Vtarc-α), and whether or not the vehicle speed V is equal to or less than the target cruise vehicle speed Vtarc. It can be replaced with the determination (V≤Vtarc-α).

10, 10A ... Vehicle 20 ... Engine (internal combustion engine, in-vehicle device, first in-vehicle device)
22 ... Generator (1st rotary electric machine) 24 ... Travel motor (2nd rotary electric machine)
30, 134 ... Third clutch (TRC clutch, switching device)
34 ... Wheels 54 ... ECU (control circuit)
76 ... Third transmission path (transmission path)
80 ... Air conditioner (in-vehicle device, second in-vehicle device)
82 ... Audio device (vehicle-mounted device, third vehicle-mounted device)
120 ... Motor generator (rotary machine)
Fdreq ... Required driving force Ngen ... Generator rotation speed Nmg ... Motor generator rotation speed Nr ... Resonance speed (resonance frequency)
Ntrc ... Rotational speed of TRC motor Rr ... Resonance region THfd ... Driving force threshold THntrc1 ... First rotation speed threshold (first frequency)
THntrc2 ... 2nd rotation speed threshold (2nd frequency)
THΔv ... Decrease amount threshold V ... Vehicle speed ΔV ... Decrease amount of vehicle speed

Claims (7)

A rotary electric machine that drives the wheels,
A transmission path for transmitting the power generated by the rotary electric machine to the wheels,
A switching device arranged on the transmission path to switch between the connected state and the non-connected state of the rotary electric machine and the wheel.
A vehicle provided with the switching device and a control circuit for controlling the rotary electric machine.
The control circuit is
A resonance region defined by a first frequency smaller than the resonance frequency of the rotary electric machine and a second frequency larger than the resonance frequency is set.
It is determined whether or not the required driving force of the vehicle is lower than the driving force threshold value and whether or not the rotational speed of the rotary electric machine is within the resonance region.
When the required driving force is lower than the driving force threshold and the rotational speed is within the resonance region, the switching device is switched to the non-connected state and the rotational speed of the rotary electric machine is removed from the resonance region. Execute suppression control,
The resonance frequency of the rotary electric machine is a resonance frequency peculiar to the stator of the rotary electric machine .
The vehicle is equipped with an internal combustion engine as an in-vehicle device that is a sound source.
The control circuit is
It is determined whether or not the load of the internal combustion engine is equal to or less than the load threshold value or whether or not the internal combustion engine is stopped.
When the load of the internal combustion engine is not equal to or less than the load threshold value, or when the internal combustion engine is not stopped, the required driving force is lower than the driving force threshold value and the rotational speed is within the resonance region. Even if there is, a vehicle characterized by limiting the resonance suppression control . A rotary electric machine that drives the wheels,
A transmission path for transmitting the power generated by the rotary electric machine to the wheels,
A switching device arranged on the transmission path to switch between the connected state and the non-connected state of the rotary electric machine and the wheel.
With the control circuit that controls the switching device and the rotary electric machine
It is a vehicle equipped with
The control circuit is
A resonance region defined by a first frequency smaller than the resonance frequency of the rotary electric machine and a second frequency larger than the resonance frequency is set.
It is determined whether or not the required driving force of the vehicle is lower than the driving force threshold value and whether or not the rotational speed of the rotary electric machine is within the resonance region.
When the required driving force is lower than the driving force threshold and the rotational speed is within the resonance region, the switching device is switched to the non-connected state, and the rotational speed of the rotary electric machine is removed from the resonance region. Execute suppression control,
The resonance frequency of the rotary electric machine is a resonance frequency peculiar to the stator of the rotary electric machine.
The vehicle includes a first vehicle-mounted device and a second vehicle-mounted device that are sound sources.
The control circuit is
Whether or not the load of the first vehicle-mounted device is equal to or less than the first load threshold value and the load of the second vehicle-mounted device is equal to or less than the second load threshold value, or the first vehicle-mounted device and the second vehicle-mounted device are stopped. Judge whether or not it is
When the load of the first in-vehicle device is not equal to or less than the first load threshold value, or when the load of the second in-vehicle device is not equal to or less than the second load threshold value, or the first in-vehicle device or the second in-vehicle device is stopped. If not, the resonance suppression control is limited even when the required driving force is lower than the driving force threshold value and the rotation speed is within the resonance region.
A vehicle characterized by that. In the vehicle according to claim 1 or 2 .
A vehicle characterized in that, in the resonance suppression control, the control circuit reduces the output of the rotary electric machine or stops the rotary electric machine. In the vehicle according to claim 3 ,
The control circuit is
During the execution of the resonance suppression control, it is monitored whether or not the decrease amount of the vehicle speed exceeds the decrease amount threshold value.
A vehicle characterized in that when the decrease amount of the vehicle speed exceeds the decrease amount threshold value, the switching device is switched from the non-connected state to the connected state, and the power generated by the rotary electric machine is increased. A rotary electric machine that drives the wheels,
A transmission path for transmitting the power generated by the rotary electric machine to the wheels,
A switching device arranged on the transmission path to switch between the connected state and the non-connected state of the rotary electric machine and the wheel.
A vehicle control method including the switching device and a control circuit for controlling the rotary electric machine.
The control circuit is
A resonance region defined by a first frequency smaller than the resonance frequency of the rotary electric machine and a second frequency larger than the resonance frequency is set.
When the predetermined condition is satisfied, it is determined whether or not the rotation speed of the rotary electric machine is within the resonance region.
When the rotation speed is within the resonance region, the switching device is switched to the non-connected state, and resonance suppression control for removing the rotation speed from the resonance region is executed.
The resonance frequency of the rotary electric machine is a resonance frequency peculiar to the stator of the rotary electric machine .
The vehicle is equipped with an internal combustion engine as an in-vehicle device that is a sound source.
The control circuit is
It is determined whether or not the load of the internal combustion engine is equal to or less than the load threshold value or whether or not the internal combustion engine is stopped.
When the load of the internal combustion engine is not equal to or less than the load threshold value, or when the internal combustion engine is not stopped, the required driving force of the vehicle is lower than the driving force threshold value and the rotational speed is within the resonance region. Even so, a vehicle control method characterized by limiting the resonance suppression control . A rotary electric machine that drives the wheels,
A transmission path for transmitting the power generated by the rotary electric machine to the wheels,
A switching device arranged on the transmission path to switch between the connected state and the non-connected state of the rotary electric machine and the wheel.
With the control circuit that controls the switching device and the rotary electric machine
It is a control method of a vehicle equipped with
The control circuit is
A resonance region defined by a first frequency smaller than the resonance frequency of the rotary electric machine and a second frequency larger than the resonance frequency is set.
When the predetermined condition is satisfied, it is determined whether or not the rotation speed of the rotary electric machine is within the resonance region.
When the rotation speed is within the resonance region, the switching device is switched to the non-connected state, and resonance suppression control for removing the rotation speed from the resonance region is executed.
The resonance frequency of the rotary electric machine is a resonance frequency peculiar to the stator of the rotary electric machine.
The vehicle includes a first vehicle-mounted device and a second vehicle-mounted device that are sound sources.
The control circuit is
Whether or not the load of the first vehicle-mounted device is equal to or less than the first load threshold value and the load of the second vehicle-mounted device is equal to or less than the second load threshold value, or the first vehicle-mounted device and the second vehicle-mounted device are stopped. Judge whether or not it is
When the load of the first in-vehicle device is not equal to or less than the first load threshold value, or when the load of the second in-vehicle device is not equal to or less than the second load threshold value, or the first in-vehicle device or the second in-vehicle device is stopped. If not, the resonance suppression control is limited even when the required driving force of the vehicle is lower than the driving force threshold value and the rotation speed is within the resonance region.
A vehicle control method characterized by that. In the vehicle control method according to claim 5 or 6 ,
The predetermined condition is a method for controlling a vehicle, which comprises selecting a rotary electric machine cruise running mode for performing cruise running by the rotary electric machine.

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