JP6327351B2 - Control device for electric vehicle - Google Patents

Description

  The present invention relates to a control device for an electric vehicle provided with a motor, a friction clutch, and a transmission in a driving force transmission system.

  2. Description of the Related Art Conventionally, a control device for a continuously variable transmission in which a shift line is set so as to cross the resonance frequency region on the shift characteristic diagram at the shortest when the engine load is a predetermined value or less is known (for example, Patent Document 1). reference).

JP-A-5-71628

  However, in the conventional device, when the load is high, it is drowned out by the engine noise and is not regarded as a sound vibration problem. However, when applied to an electric vehicle having a motor as a drive source, the noise level is low. The problem remains that it is necessary to avoid resonance.

  The present invention has been made paying attention to the above problems, and an object of the present invention is to provide a control device for an electric vehicle capable of solving the sound vibration problem while suppressing the deterioration of the power consumption.

In order to achieve the above object, an electric vehicle of the present invention includes a motor, a friction clutch, and a transmission in a driving force transmission system.
In this electric vehicle, there is provided a resonance avoidance controller that performs control to prevent the motor operating point based on the motor rotation speed and the motor torque from staying in the resonance region during acceleration.
When the motor operating point passes through the resonance region, the resonance avoidance controller selects the shift control of the transmission if the driving force is below a predetermined value, and controls the slip of the friction clutch if the driving force exceeds a predetermined value. Resonance avoidance control to select is executed .

Therefore, when the motor operating point passes through the resonance region, if the driving force is equal to or less than a predetermined value, the transmission shift control is selected, and resonance is caused by the shift control that increases the transmission input rotational speed (= motor rotational speed). Pass quickly through the area. On the other hand, when the traveling driving force exceeds a predetermined value, the slip control of the friction clutch is selected, and the resonance region is quickly passed by the slip control that causes the friction clutch to slip by the increase in the motor rotation speed.
That is, when the slip control is performed, the resonance region can be avoided regardless of the driving force. However, the slip control alone causes heat loss due to slipping of the friction clutch, which causes a deterioration in power consumption. On the other hand, when the traveling driving force is less than a predetermined value and there is a motor torque margin and the driving force does not become deficient even when shifting is performed, switching to shift control is used to suppress deterioration in power consumption.
As a result, by switching and using the two systems of control for avoiding the resonance region, it is possible to suppress the deterioration of power consumption and solve the sound vibration problem.

1 is an overall system diagram illustrating an electric vehicle with an automatic transmission to which a control device according to a first embodiment is applied. 6 is a flowchart illustrating a flow of resonance avoidance control processing executed by the integrated controller of the first embodiment. It is a figure which shows the control judgment map used for judgment whether resonance avoidance is possible by down shift control in the resonance avoidance control process of Example 1. FIG. FIG. 6 is a motor characteristic diagram showing an MG operating point when resonance avoidance is possible by downshift control in the resonance avoidance control processing of the first embodiment. FIG. 6 is a motor characteristic diagram showing an MG operating point when resonance avoidance is not possible with downshift control in the resonance avoidance control processing of the first embodiment. Brake, accelerator pedal, vehicle speed, travel driving force, motor torque, clutch command torque, clutch control status, gear ratio, gear ratio avoidable torque margin flag when resonance is avoided by shift control in the resonance avoidance control processing of the first embodiment It is a time chart which shows each characteristic of a resonance avoidance request flag, motor rotation speed, and transmission input rotation speed. Brake, accelerator pedal, vehicle speed, driving force, motor torque, clutch command torque, clutch control status, gear ratio, gear ratio avoidable torque margin flag when resonance is avoided by slip control in the resonance avoidance control processing of the first embodiment It is a time chart which shows each characteristic of a resonance avoidance request flag, motor rotation speed, and transmission input rotation speed. It is a whole system figure which shows the continuously variable transmission mounted electric vehicle to which the control apparatus of Example 2 was applied. Brake, accelerator pedal, vehicle speed, travel driving force, motor torque, clutch command torque, clutch control state, gear ratio, gear ratio avoidable torque margin flag when resonance is avoided by shift control in the resonance avoidance control processing of the second embodiment It is a time chart which shows each characteristic of a resonance avoidance request flag, motor rotation speed, and transmission input rotation speed. It is a whole system figure which shows the dual clutch transmission mounting electric vehicle to which the control apparatus of Example 3 was applied. Brake, accelerator pedal, vehicle speed, travel driving force, motor torque, high side clutch command torque, low side clutch command torque, high side clutch control state when resonance is avoided by shift control in the resonance avoidance control process of the third embodiment. 6 is a time chart showing characteristics of a low-side clutch control state, an equivalent gear ratio, a shift-allowable torque margin flag, a resonance avoidance request flag, a motor speed, and a transmission input speed.

  Hereinafter, the best mode for realizing an electric vehicle control device of the present invention will be described based on Examples 1 to 3 shown in the drawings.

  First, the configuration will be described.

  The configuration of the control device of the automatic transmission-equipped electric vehicle (an example of an electric vehicle) in the first embodiment will be described separately as “overall system configuration” and “resonance avoidance control configuration”.

[Overall system configuration]
FIG. 1 shows an electric vehicle A1 equipped with an automatic transmission to which the control device of the first embodiment is applied. The overall system configuration will be described below with reference to FIG.

  As shown in FIG. 1, a motor / generator 1 (motor), a friction clutch 2, an automatic transmission 3 (transmission), and drive wheels 4 are included in the drive system of the electric vehicle A 1 equipped with an automatic transmission. I have.

  The motor / generator 1 is a three-phase AC rotating electric machine provided as a travel drive source. An inverter 5 and a battery 6 are connected to the motor / generator 1. The inverter 5 is torque-controlled by the motor controller 10 and converts the direct current discharged from the battery 6 into a three-phase alternating current to drive the motor / generator 1 during power running with a positive target torque. During regeneration in which the target torque is negative, the three-phase alternating current generated by the motor / generator 1 rotated by the drive wheels 4 is converted into direct current and the battery 6 is charged.

  The friction clutch 2 is provided as a starting clutch, and its engagement / release is controlled by a command from the AT controller 11. As shown in FIG. 1, the friction clutch 2 may be disposed independently between the motor / generator 1 and the automatic transmission 3, or is incorporated in the automatic transmission 3 as a clutch not involved in gear shifting. You may do it.

  The automatic transmission 3 is a transmission that obtains stepped gears (for example, first gear and second gear), and upshift control or downshift control is performed according to a command from the AT controller 11. The transmission output of the automatic transmission 3 is transmitted to the left and right drive wheels 4 via a propeller shaft, a differential gear, and the like.

  As shown in FIG. 1, the control system of the electric vehicle A1 equipped with the automatic transmission includes a motor controller 10, an AT controller 11, and an integrated controller 12. The motor controller 10, the AT controller 11, and the integrated controller 12 are connected by a CAN communication line 13 that can exchange information.

  The motor controller 10 controls the motor / generator 1 according to a command from the inverter 5. As the motor control by the motor controller 10, torque control for controlling the actual motor torque so as to coincide with the target motor torque is performed. In normal torque control during traveling, control is performed such that the traveling driving force is calculated according to the accelerator opening and the vehicle speed, and the traveling driving force is set as the target motor torque. As motor control by the motor controller 10, in addition to torque control, rotation speed control for controlling the actual motor rotation speed so as to coincide with the target motor rotation speed is performed. In this rotational speed control, control is performed to make the actual motor rotational speed coincide with the target motor rotational speed while outputting motor torque corresponding to fluctuations in the drive system load applied to the motor / generator 1.

  The AT controller 11 performs shift control of the automatic transmission 3 as well as engagement / release control of the friction clutch 2. In normal shift control, a shift map with vehicle speed and accelerator opening as parameters is used. For example, when the vehicle operating point (a point determined by the vehicle speed and accelerator opening) crosses the up shift line, an up shift request is issued and the down shift request is issued. When the speed change line is crossed, a down speed change request is issued.

  The integrated controller 12 is a controller that integrates and controls the motor / generator 1, the friction clutch 2, and the automatic transmission 3 included in the drive system, and outputs a control command to the motor controller 10 and the AT controller 11. The integrated controller 12 receives information from a transmission input rotational speed sensor 14, an accelerator opening sensor 15, a vehicle speed sensor 16, a motor rotational speed sensor 17, a motor torque sensor 18, a brake switch 19, and the like.

[Resonance avoidance control configuration]
FIG. 2 shows a flow of resonance avoidance control processing executed by the integrated controller 12 of the first embodiment (resonance avoidance controller). Hereinafter, each step of FIG. 2 representing the resonance avoidance control processing configuration will be described.

In step S1, it is determined whether the actual rotational speed of the motor / generator 1 has increased and has reached the vicinity of the motor resonant rotational speed region. If YES (reached near the resonance region), the process proceeds to step S2, and if NO (reasons near the resonance region), the determination in step S1 is repeated.
Here, the motor resonance rotation speed region is a region set as a resonance region at the time of acceleration, and when the first motor rotation speed before entering the motor resonance rotation speed region is reached, the motor resonance rotation speed region has reached the vicinity of the motor resonance rotation speed region. And resonance avoidance control is started. When the second motor rotation speed after exiting the motor resonance rotation speed area is reached, it is determined that the vicinity of the motor resonance rotation speed area has been passed, and the resonance avoidance control is terminated (step S5).

In step S2, following the determination that the vicinity of the resonance region has been reached in step S1, or the determination that the vicinity of the resonance region has not passed in step S5, the vehicle speed Vsp, the driving force, and the control determination map shown in FIG. It is determined whether or not the motor resonance rotation speed region (resonance point) can be avoided by shifting. If YES (shifting avoidance is possible), the process proceeds to step S3. If NO (shifting avoidance is not possible), the process proceeds to step S6.
Here, the vehicle speed Vsp is acquired from the vehicle speed sensor 16. The travel driving force is calculated as the driver's required driving force from the accelerator opening and the vehicle speed Vsp. The predetermined value of the control determination map shown in FIG. 3 is a boundary value indicating whether or not the motor / generator 1 can actually output the required motor rotation speed and motor torque when it is assumed that the shift control is performed. As shown in FIG. 3, when the vehicle speed Vsp is in a region below a predetermined vehicle speed and the travel drive force is less than a predetermined value (point B), the shift control of the automatic transmission 3 is selected and the travel drive force is selected. Is greater than a predetermined value (point C), the slip control of the friction clutch 2 is selected.

  In step S3, following the determination that the shift can be avoided in step S2, shift control is performed so as to prevent the motor operating point from staying in the motor resonance rotational speed region by shifting from down shift to up shift. Start and go to step S4.

In step S4, following the start of shifting in step S3, clutch control for reducing the instruction torque to the friction clutch 2, and the motor rotational speed is increased with the transmission input rotational speed crossing the motor resonance rotational speed region as the target rotational speed. The downshift assist control of the automatic transmission 3 by the motor rotation speed control is performed, and the process proceeds to step S5.
Here, in the downshift of the resonance avoidance shift, the motor resonance rotation speed region is quickly passed during the downshift. After passing through the motor resonance rotation speed region, the shift from the down shift to the up shift is performed, and the motor rotation speed control is performed to maintain the motor rotation speed by the up shift.

  In step S5, following the downshift assist control in step S4 or the slip control of the friction clutch 2 in step S7, it is determined whether or not the vicinity of the motor resonance rotational speed region has been passed. If YES (passing near the resonance region), the process proceeds to the end. If NO (passing near the resonance region), the process returns to step S2.

  In step S6, following the determination in step S2 that the shift cannot be avoided, the clutch control for maintaining the instruction torque to the friction clutch 2 and the clutch slip rotation speed across the motor resonance rotation speed range are set as targets. The slip-in control of the friction clutch 2 is performed by the motor rotation speed control that starts increasing the motor rotation speed as the rotation speed, and the process proceeds to step S7.

  In step S7, following the slip-in control in step S6, after the slip-in control, the slip control of the friction clutch 2 that increases the motor rotational speed to the target rotational speed crossing the motor resonance rotational speed region is performed, and the process proceeds to step S5.

Next, the operation will be described.
The functions of the control device for the electric vehicle A1 equipped with the automatic transmission according to the first embodiment are changed to "resonance avoidance control action", "resonance avoidance speed change action", "resonance avoidance slip action", and "other characteristic actions of resonance avoidance control". Separately described.

[Resonance avoidance control action]
When the motor rotation speed reaches the vicinity of the motor resonance rotation speed area and when the motor resonance rotation speed area can be avoided by gear shifting, in the flowchart of FIG. 2, step S1, step S2, step S3, step S4 → Proceed to step S5. Then, the flow from step S2 to step S3 to step S4 to step S5 is repeated until it is determined in step S5 that the vicinity of the motor resonance rotational speed region has been passed by the shift control.
That is, the resonance avoidance shift control is selected because the motor resonance rotation speed region can be avoided by the shift. In step S3, shift control is started, and in next step S4, downshift assist control of the automatic transmission 3 is performed by clutch control and motor rotation speed control. If it is determined in step S5 that the vicinity of the motor resonance rotational speed region has been passed by the shift control, the process proceeds from step S5 to the end and the resonance avoidance control is terminated.

When the motor rotation speed reaches the vicinity of the motor resonance rotation speed area and when it is impossible to avoid the motor resonance rotation speed area by shifting, in the flowchart of FIG. 2, step S1, step S2, step S6, step The process proceeds from S7 to step S5. Then, the flow from step S2 to step S6 to step S7 to step S5 is repeated until it is determined in step S5 that the vicinity of the motor resonance rotation speed region has been passed by the shift control.
That is, the resonance avoidance slip control is selected because it is impossible to avoid the motor resonance rotation speed region by shifting. In step S6, slip-in control of the friction clutch 2 is performed by clutch control and motor rotation speed control. In the next step S7, slip control for increasing the motor rotation speed is performed. When it is determined in step S5 that the vicinity of the motor resonance rotational speed region has been passed by the shift control, the process proceeds from step S5 to the end, and the resonance avoidance control is terminated.

In this way, when the motor rotation speed increases and reaches the vicinity of the motor resonance rotation speed region, in step S2, the vehicle resonance speed rotation region (resonance) is determined using the vehicle speed Vsp, the travel driving force, and the control determination map shown in FIG. It is determined whether the point) can be avoided by shifting. That is, as shown in FIG. 3, there is a shift margin when the vehicle speed Vsp is a predetermined vehicle speed or less and the travel driving force is below a predetermined value which is the maximum motor torque value when it is assumed that the shift control is performed. In the case of B, the shift control of the automatic transmission 3 is selected.
In the case of the point B having this shift margin, as shown in FIG. 4, when the MG operation point B1 without a shift exists in the resonance region, the MG operation point B2 after the shift is out of the resonance region, and the motor / The maximum motor torque value (predetermined value) of the generator 1 is not exceeded. The MG operation points B1 and B2 are operation points on the same request output line.

On the other hand, as shown in FIG. 3, the vehicle speed Vsp is in the region below the predetermined vehicle speed, and the driving force exceeds the predetermined value which is the maximum motor torque value when it is assumed that the shift control is performed. In the case of point C, the slip control of the friction clutch 2 is selected.
In the case of the point C where there is no shift margin, as shown in FIG. 5, when the MG operation point C1 without a shift exists in the resonance region, the MG operation point C2 after the shift is out of the resonance region. The maximum motor torque value (predetermined value) of the generator 1 will be exceeded. Therefore, as shown in the MG operation point C3 at the time of slip, it is necessary to remove the resonance region by moving the operation point from C1 to C3 by the slip control of the friction clutch 2.

As described above, in the first embodiment, when the motor operating point passes through the resonance region, the shift control of the automatic transmission 3 is selected when the traveling driving force is equal to or less than the predetermined value, and the traveling driving force exceeds the predetermined value. Is configured to select the slip control of the friction clutch 2.
Therefore, when the shift control of the automatic transmission 3 is selected, the resonance region can be quickly passed by the down shift control that increases the transmission input rotation speed (= motor rotation speed). On the other hand, when the slip control of the friction clutch 2 is selected, the resonance region can be quickly passed by the slip control that increases the motor rotation speed.
That is, it is possible to avoid the resonance region by performing the slip control even in a state where the running drive force shortage is predicted only by the shift control. However, the slip control alone causes heat loss due to slipping of the friction clutch, which causes a deterioration in power consumption. On the other hand, when the travel driving force is less than or equal to a predetermined value and there is a margin in the motor torque even when shifting is performed and the driving force does not become insufficient, switching to downshift control can be used to suppress deterioration in power consumption. As a result, by switching and using the two systems of control for avoiding the resonance region, it is possible to suppress the deterioration of power consumption and solve the sound vibration problem.

[Resonance avoidance shift action]
FIG. 6 shows each characteristic when resonance is avoided by shift control in the resonance avoidance control process of the first embodiment. Hereinafter, the resonance avoidance shift operation will be described based on the time chart of FIG.

  In FIG. 6, time t1 is a brake-off operation time, and time t2 is an accelerator depression start time intended to start. At time t2, the vehicle speed, travel driving force, motor torque, clutch command torque, motor rotation speed, and transmission input rotation speed start to increase. Then, at time t3 immediately after accelerator depression start time t2, the accelerator depression amount is maintained. Then, when the motor speed increases from time t2 and reaches the resonance avoidance request determination speed (<first motor speed) at time t4, a resonance avoidance request flag is set. Subsequently, when the motor rotation speed reaches the first motor rotation speed in the vicinity of the motor resonance rotation speed region at time t5, the resonance avoidance shift is started.

  In the resonance avoidance shift, from time t5 to time t6, the clutch control for reducing the instruction torque to the friction clutch 2 and the motor rotational speed is increased with the transmission input rotational speed crossing the motor resonant rotational speed region as the target rotational speed. The downshift assist control (Ratio) of the automatic transmission 3 by the motor rotation speed control is performed. Then, during the downshift assist control from time t5 to time t6, the motor rotation speed quickly passes through the motor resonance rotation speed region. Here, from time t5 to time t6, since clutch control is performed to reduce the command torque to the friction clutch 2, the drive system load applied to the motor / generator 1 is reduced, and the motor speed is increased by the speed control. However, the motor torque decreases.

  Then, at time t6, after passing through the motor resonance rotational speed region, the shift from the downshift to the gentle upshift is performed, and from time t6 to time t7 when the second motor rotational speed is reached, the moderate upshift (Ratio ), The motor rotation speed control for maintaining the motor rotation speed is performed. Here, the reason why a gradual upshift can be performed by the stepped automatic transmission 3 is that the friction clutch 2 is in the slip engagement state. Further, the reason why the motor rotation speed can be maintained is that the vehicle speed (= transmission output rotation speed) increases in the section from time t6 to t7.

  Further, when the motor rotation speed increases from time t7 and reaches the resonance avoidance completion determination rotation speed (> second motor rotation speed) at time t8, the resonance avoidance request flag is cleared. That is, from time t5 to time t7 is a resonance avoidance speed change section that quickly passes through the motor resonance rotation speed region while maintaining the traveling driving force by the slip engagement state of the friction clutch 2. Note that by shifting from a down shift to a gradual up shift in the resonance avoidance shift section, the speed ratio before the resonance avoidance shift section and the speed ratio after the resonance avoidance shift section are maintained at the same speed ratio (speed stage). .

[Resonance avoidance slip action]
FIG. 7 shows each characteristic when resonance is avoided by slip control in the resonance avoidance control process of the first embodiment. Hereinafter, the resonance avoidance slip action will be described based on the time chart of FIG.

  In FIG. 7, time t1 is a brake-off operation time, and time t2 is an accelerator depression start time intended to start. At time t2, the vehicle speed, travel driving force, motor torque, clutch command torque, motor rotation speed, and transmission input rotation speed start to increase. Then, at time t3 immediately after the accelerator depression start time t2, the flag indicating that there is a shift avoidable torque margin is lowered. Then, when the motor speed increases from time t2 and reaches the resonance avoidance request determination speed (<first motor speed) at time t4, a resonance avoidance request flag is set. Subsequently, when the motor rotation speed reaches the first motor rotation speed in the vicinity of the motor resonance rotation speed region at time t5, resonance avoidance slip is started.

  In the resonance avoidance slip, from time t5 to time t6, the slip control of the friction clutch 2 is performed by the motor rotational speed control in which the motor rotational speed is increased with the clutch slip rotational speed crossing the motor resonant rotational speed region as the target rotational speed. At this time, the instruction torque and the gear ratio to the friction clutch 2 are maintained. Then, due to the increase in the motor rotation speed by the slip control of the friction clutch 2 from time t5 to time t6, the motor rotation speed quickly passes through the motor resonance rotation speed region. From time t5 to time t6, the motor torque is maintained while increasing the motor rotation speed.

  Then, from the time t6 after passing through the motor resonance rotation speed region to the time t7 when reaching the second motor rotation speed, the motor rotation speed control for maintaining the motor rotation speed at the time t6 is performed. Further, when the motor rotation speed increases from time t7 and reaches the resonance avoidance completion determination rotation speed (> second motor rotation speed) at time t8, the resonance avoidance request flag is cleared. That is, from time t5 to time t7 is a resonance avoidance slip section that quickly passes through the motor resonance rotation speed region while maintaining the instruction torque and the travel driving force to the friction clutch 2. Note that, in the resonance avoidance slip section, the difference in rotational speed between the motor rotational speed and the transmission input rotational speed is the slip amount of the friction clutch 2.

[Other characteristic effects of resonance avoidance control]
In the first embodiment, the predetermined value of the driving force is a boundary value that determines whether or not the motor / generator 1 can actually output the required motor rotation speed and motor torque when it is assumed that the shift control is performed. It was.
That is, if the predetermined value of the driving force is set to a low value, the frequency at which the resonance avoidance shift is selected decreases, and the power consumption deteriorates. On the other hand, if the predetermined value of the driving force is set to a high value, the resonance avoidance shift is selected more frequently. However, the motor operating point when the shift is executed exceeds the allowable output range of the motor characteristics, and the motor Problems such as durability arise.
On the other hand, by setting the motor operating point at the time of shifting to a predetermined value based on the boundary value of the output range of motor characteristics, it is possible to achieve both suppression of power consumption deterioration and securing of motor durability reliability. It is done.

In the first embodiment, a motor resonance rotational speed region is set as a resonance region at the time of acceleration. When the actual rotational speed of the motor / generator 1 increases and reaches the first motor rotational speed before entering the motor resonant rotational speed region, resonance occurs. The avoidance control is selected, and the selected resonance avoidance control is started.
That is, when deciding when to start resonance avoidance control, resonance will occur if the start of resonance avoidance control is delayed. If the resonance avoidance control is started too early, the intervention time for shift control and slip control in a start scene that is not originally performed becomes longer, which gives the passenger a sense of incongruity.
On the other hand, when the first motor rotation speed before entering the motor resonance rotation speed region is reached, resonance avoidance control is selected and started so that resonance avoidance control can be performed at an appropriate timing without causing resonance or feeling of strangeness. Be started.

In the first embodiment, when it is determined that the shift control of the automatic transmission 3 can be avoided, the clutch control for reducing the instruction torque to the friction clutch 2 and the transmission input rotation speed crossing the motor resonance rotation speed region are set. The configuration is such that the downshift assist control of the automatic transmission 3 is performed by the motor rotation speed control that increases the motor rotation speed as the target rotation speed.
That is, if resonance is to be avoided by downshift assist control by motor rotation speed control while maintaining the instruction torque to the friction clutch 2, the motor rotation speed is increased to counter the engagement load of the friction clutch 2. Torque increases. In this case, the motor operating point may exceed the allowable output range of the motor characteristics. Further, when the motor torque (the input side torque of the automatic transmission 3) is increased, the increase of the output side torque (traveling driving force) of the automatic transmission 3 due to the downshift is further increased.
On the other hand, in the case of the resonance avoidance speed change control, by using the clutch control for reducing the instruction torque to the friction clutch 2, the driving force of the motor can be increased even if the motor operating point exceeds the allowable output range of the motor characteristics. Is also prevented.

In the first embodiment, when it is determined that the shift control of the automatic transmission 3 cannot be avoided, the clutch control for maintaining the instruction torque to the friction clutch 2 and the clutch slip rotation speed across the motor resonance rotation speed region are maintained. The slip control of the friction clutch 2 is performed by the motor rotation speed control for increasing the motor rotation speed with the target rotation speed as the target rotation speed.
That is, in the case of resonance avoidance by slip control, if there is no speed change and the instruction torque to the friction clutch 2 is reduced, the output side torque (traveling driving force) of the automatic transmission 3 is reduced as it is.
On the other hand, in the case of resonance avoidance slip control, it is possible to prevent the driving force from being lowered by using the clutch control for maintaining the instruction torque to the friction clutch 2 together.

In the first embodiment, when it is determined that the shift control of the automatic transmission 3 can be avoided, the shift control for shifting from the down shift to the up shift is performed, and the motor resonance rotation speed region is passed during the down shift. The motor rotation speed control is performed to maintain the motor rotation speed after passing through the motor resonance rotation speed region by the upshift.
That is, the increase in the output side torque (traveling driving force) of the automatic transmission 3 due to the downshift passing through the motor resonance rotational speed region is the decrease in the output side torque (traveling driving force) of the automatic transmission 3 due to the upshift. Canceled by.
Therefore, in the case of the resonance avoidance shift control, the shift driving force before and after the resonance avoidance control can be suppressed by performing the shift control that shifts to the upshift that maintains the transmission input rotation speed after the downshift. .

Next, the effect will be described.
In the control device for the electric vehicle A1 equipped with the automatic transmission according to the first embodiment, the effects listed below can be obtained.

(1) In an electric vehicle (electric vehicle A1 equipped with an automatic transmission) having a driving force transmission system including a motor (motor / generator 1), a friction clutch 2 and a transmission (automatic transmission 3),
A resonance avoidance controller (FIG. 2) is provided for performing control to prevent the motor operating point due to the motor rotation speed and motor torque of the motor (motor / generator 1) from staying in the resonance region during acceleration.
The resonance avoidance controller (integrated controller 12, FIG. 2) selects the shift control of the transmission (automatic transmission 3) when the driving force is below a predetermined value when the motor operating point passes through the resonance region, and travels. When the driving force exceeds a predetermined value, the slip control of the friction clutch 2 is selected.
For this reason, it is possible to solve the sound vibration problem while suppressing the deterioration of the power consumption.

(2) The resonance avoidance controller (integrated controller 12, FIG. 2) calculates the required motor rotation speed and motor torque when the predetermined value of the driving force is subjected to shift control. Is a boundary value indicating whether or not it can actually be output (FIG. 3).
For this reason, in addition to the effect of (1), it is possible to achieve both suppression of deterioration of electric power consumption and securing of motor durability reliability.

(3) The resonance avoidance controller (integrated controller 12, FIG. 2) sets a motor resonance rotation speed region as a resonance region at the time of acceleration, and avoids resonance when the first motor rotation speed before entering the motor resonance rotation speed region is reached. The control is selected and the selected resonance avoidance control is started.
For this reason, in addition to the effect of (1) or (2), the resonance avoidance control can be started at an appropriate timing that does not give rise to the occurrence of resonance or a sense of incongruity.

(4) When it is determined that the resonance avoidance controller (integrated controller 12, FIG. 2) can be avoided by the shift control of the transmission (automatic transmission 3), clutch control that reduces the instruction torque to the friction clutch 3 Downshift assist control of the transmission (automatic transmission 3) is performed by the motor rotation speed control for increasing the motor rotation speed with the transmission input rotation speed crossing the motor resonance rotation speed region as the target rotation speed (FIG. 6). ).
For this reason, in addition to the effect of (3), in the case of the resonance avoidance speed change control, it is possible to prevent the motor operating point from exceeding the allowable output range of the motor characteristics by using the clutch control for reducing the instruction torque to the friction clutch 2 together. In addition to preventing this, it is possible to prevent the traveling driving force from increasing.

(5) When it is determined that the resonance avoidance controller (integrated controller 12, FIG. 2) cannot be avoided by the shift control of the transmission (automatic transmission 3), the instruction torque to the friction clutch 2 is maintained. The slip control of the friction clutch 2 is performed by the clutch control and the motor rotational speed control for increasing the motor rotational speed with the clutch slip rotational speed crossing the motor resonance rotational speed region as the target rotational speed (FIG. 7).
For this reason, in addition to the effect of (3), in the case of resonance avoidance slip control, it is possible to prevent the travel driving force from being lowered by using the clutch control for maintaining the command torque to the friction clutch 2 in combination.

(6) The transmission is a stepped automatic transmission 3,
When it is determined that the resonance avoidance controller (integrated controller 12, FIG. 2) can be avoided by the shift control of the automatic transmission 3, the friction clutch 2 is brought into the slip engagement state, and the shift shifts from the down shift to the up shift. In addition to the control, the motor rotation speed control is performed to pass the motor resonance rotation speed region during the downshift and maintain the motor rotation speed after passing the motor resonance rotation speed region by the upshift (FIG. 6).
For this reason, in addition to the effect of (4), in the case of the resonance avoidance shift control by the automatic transmission 3, by performing the shift control that shifts to the up shift that maintains the transmission input rotation speed after the down shift, the resonance is achieved. A change in the driving force before and after the avoidance control can be suppressed.

  The second embodiment is an example in which a continuously variable transmission that continuously changes a gear ratio is used as a transmission.

  First, the system configuration will be described.

  FIG. 8 shows a continuously variable transmission-equipped electric vehicle A2 to which the control device of the second embodiment is applied. The overall system configuration will be described below with reference to FIG.

  As shown in FIG. 8, the drive system of the continuously variable transmission-equipped electric vehicle A <b> 2 includes a motor / generator 1 (motor), a friction clutch 2, a continuously variable transmission 7 (transmission), and drive wheels 4. It is equipped with.

  The continuously variable transmission 7 is a belt-type continuously variable transmission or the like that obtains a continuously variable transmission ratio, and up-shift control or down-shift control is performed according to a command from the CVT controller 21. The transmission output of the continuously variable transmission 7 is transmitted to the left and right drive wheels 4 via a propeller shaft, a differential gear, and the like.

As shown in FIG. 8, the control system of the continuously variable transmission-equipped electric vehicle A <b> 2 includes a motor controller 10, a CVT controller 21, and an integrated controller 12. The motor controller 10, the CVT controller 21, and the integrated controller 12 are connected by a CAN communication line 13 that can exchange information.
Since other system configurations are the same as those in the first embodiment, description thereof is omitted. [Resonance avoidance control configuration] is the same as that shown in FIG.

  Next, the resonance avoidance speed change operation will be described.

  FIG. 9 shows each characteristic when resonance is avoided by shift control in the resonance avoidance control process of the second embodiment. Hereinafter, the resonance avoidance shift operation will be described based on the time chart of FIG.

  In FIG. 9, time t1 is a brake-off operation time, and time t2 is an accelerator depression start time intended to start. At time t2, the vehicle speed, travel driving force, motor torque, clutch command torque, motor rotation speed, and transmission input rotation speed start to increase. Then, at time t3 immediately after accelerator depression start time t2, the accelerator depression amount is maintained. Then, when the motor speed increases from time t2 and reaches the resonance avoidance request determination speed (<first motor speed) at time t4, a resonance avoidance request flag is set. Subsequently, when the motor rotation speed reaches the first motor rotation speed in the vicinity of the motor resonance rotation speed region at time t5, the resonance avoidance shift is started.

  In the resonance avoidance shift, time t5 to time t6 is the first upshift section. In this section (t5 to t6), the clutch control for gradually increasing the command torque to the friction clutch 2 and the motor rotational speed are moderated with the transmission input rotational speed immediately before the motor resonant rotational speed region as the target rotational speed. Ascending motor rotation speed control is performed. That is, the motor rotation speed is brought close to the motor resonance rotation speed region by a gradual upshift (Ratio) that gradually changes the gear ratio. From time t6 to time t7 is a downshift section. In this section (t6 to t7), clutch control for reducing the instruction torque to the friction clutch 2 and motor rotation speed control for increasing the motor rotation speed with the transmission input rotation speed crossing the motor resonance rotation speed area as the target rotation speed. Then, downshift assist control (Ratio) of the automatic transmission 3 is performed. During the downshift assist control from time t6 to time t7, the motor rotation speed quickly passes through the motor resonance rotation speed region. Here, from time t6 to time t7, since clutch control is performed to reduce the instruction torque to the friction clutch 2, the drive system load applied to the motor / generator 1 is reduced, and the motor speed is increased by speed control. However, the motor torque decreases.

  Then, at time t7, after passing through the motor resonance rotational speed region, the shift from the downshift to the gentle upshift is performed, and from time t7 to the time t8 when the second motor rotational speed is reached, the moderate upshift (Ratio ), The motor rotation speed control for maintaining the motor rotation speed is performed. The reason why the motor rotational speed can be maintained by the moderate upshift is that the vehicle speed (= transmission output rotational speed) increases in the section from time t7 to t8.

  Further, when the motor rotation speed increases from time t8 and reaches resonance avoidance completion determination rotation speed (> second motor rotation speed) at time t9, the resonance avoidance request flag is cleared. In other words, the period from time t5 to time t8 is a resonance avoidance speed change section that quickly passes through the motor resonance rotation speed region while maintaining the travel driving force by the engaged state of the friction clutch 2. In addition, the shift ratio after the resonance avoidance shift section becomes slightly higher than the speed ratio before the resonance avoidance shift section by shifting from a moderate upshift to a downshift to a gentle upshift in the resonance avoidance shift section. .

As described above, in the second embodiment, when it is determined that the shift control of the continuously variable transmission 7 can be avoided, the shift control for shifting from the upshift to the downshift to the upshift is performed. At the same time, the motor rotation speed approaches the motor resonance rotation speed area by the first upshift, passes through the motor resonance rotation speed area during the downshift, and the motor rotation after passing the motor resonance rotation speed area by the subsequent upshifting. The motor rotation speed control is performed to maintain the number.
That is, by utilizing the degree of freedom of the speed change control and the good speed change quality of the continuously variable transmission 7, the resonance avoidance control is started slightly earlier than the first embodiment, and the motor speed is brought close to the motor resonance speed range for the first time. Change gears. As a result, in the next downshift, the motor rotation speed quickly passes through the motor resonance rotation speed region. In addition, the increase in the output side torque (traveling driving force) of the automatic transmission 3 due to the downshift that passes through the motor resonance rotational speed region is the output side torque (traveling driving force) of the automatic transmission 3 due to the subsequent upshift. Canceled by descent of
Therefore, in the case of the resonance avoidance shift control by the continuously variable transmission 7, the shift from the upshift → the downshift → the upshift is made to ensure that the motor resonance rotation speed region passes through the downshift and before and after the resonance avoidance control. Changes in the driving force of the vehicle can be suppressed. Since other operations are the same as those of the first embodiment, description thereof is omitted.

Next, the effect will be described.
In the control device for the continuously variable transmission-equipped electric vehicle A2 according to the second embodiment, the following effects can be obtained.

(7) The transmission is a continuously variable transmission 7,
When it is determined that the resonance avoidance controller (integrated controller 12, FIG. 2) can be avoided by the shift control of the continuously variable transmission 7, the resonance avoidance controller performs shift control for shifting from upshift → downshift → upshift, The motor speed is brought close to the motor resonance speed area by the first upshift, passes through the motor resonance speed area during the downshift, and maintains the motor speed after passing through the motor resonance speed area by the subsequent upshift. The motor speed control is performed (FIG. 9).
For this reason, in addition to the effect of (4), in the case of the resonance avoidance shift control by the continuously variable transmission 7, it is possible to reliably pass through the motor resonance rotational speed region by the downshift by shifting from the upshift → downshift → upshift. In addition, it is possible to suppress a change in the driving force before and after the resonance avoidance control.

  The third embodiment is an example in which a dual clutch transmission that switches between a high gear and a low gear is used as the transmission.

  First, the system configuration will be described.

  FIG. 10 shows a dual clutch transmission-equipped electric vehicle A3 to which the control device of the third embodiment is applied. The overall system configuration will be described below with reference to FIG.

  As shown in FIG. 10, the drive system of the electric vehicle A3 equipped with the dual clutch transmission includes a motor / generator 1 (motor), a dual clutch transmission 8 (friction clutch, transmission), and drive wheels 4. I have.

  The dual clutch transmission 8 includes a high-side clutch 8a and a low-side clutch 8b as friction clutches, and a high transmission mechanism 8c and a low transmission mechanism 8d as transmission mechanisms. When the high side clutch 8a is engaged, a high gear stage that transmits the driving force via the high transmission mechanism 8c is selected, and when the low side clutch 8b is engaged, the low gear that transmits the driving force via the low transmission mechanism 8d is selected. A gear stage is selected. Then, up-shift control (low shift stage → high shift stage) or down shift control (high shift stage → low shift stage) is performed according to a command from the DCT controller 31. The transmission output of the dual clutch transmission 8 is transmitted to the left and right drive wheels 4 via a propeller shaft, a differential gear, and the like.

As shown in FIG. 10, the control system of the electric vehicle A <b> 3 equipped with the dual clutch transmission includes a motor controller 10, a DCT controller 31, and an integrated controller 12. The motor controller 10, the DCT controller 31, and the integrated controller 12 are connected by a CAN communication line 13 that can exchange information.
Since other system configurations are the same as those in the first embodiment, description thereof is omitted. [Resonance avoidance control configuration] is the same as that shown in FIG.

  Next, the resonance avoidance speed change operation will be described.

  FIG. 11 shows each characteristic when resonance is avoided by shift control in the resonance avoidance control process of the third embodiment. Hereinafter, the resonance avoidance speed change operation will be described based on the time chart of FIG.

  In FIG. 11, time t1 is a brake-off operation time, and time t2 is an accelerator depression start time intended to start. At time t2, the vehicle speed, travel driving force, motor torque, high-side clutch command torque, motor rotation speed, and transmission input rotation speed start to increase. Then, at time t3 immediately after accelerator depression start time t2, the accelerator depression amount is maintained. Then, when the motor speed increases from time t2 and reaches the resonance avoidance request determination speed (<first motor speed) at time t4, a resonance avoidance request flag is set. Subsequently, when the motor rotation speed reaches the first motor rotation speed in the vicinity of the motor resonance rotation speed region at time t5, the resonance avoidance shift is started.

  In the resonance avoidance shift, from time t5 to time t6, clutch control for decreasing the instruction torque to the high side clutch 8a and increasing the instruction torque to the low side clutch 8b, and transmission input across the motor resonance rotation speed region The downshift assist control (equivalent gear ratio) of the automatic transmission 3 is performed by the motor rotation speed control for increasing the motor rotation speed with the rotation speed as the target rotation speed. Then, during the downshift assist control from time t5 to time t6, the motor rotation speed quickly passes through the motor resonance rotation speed region. Here, from time t5 to time t6, clutch control is performed so that the decrease in the instruction torque to the high-side clutch 8a is greater than the increase in the instruction torque to the low-side clutch 8b. The system load is reduced, and the motor torque is reduced while the motor rotational speed is increased by the rotational speed control.

  Then, at time t6, after passing through the motor resonance rotational speed region, the shift from the downshift to the gentle upshift is performed, and from time t6 to the time t7 when the second motor rotational speed is reached, the moderate upshift (corresponding to The motor speed control is performed to maintain the motor speed by the gear ratio. Here, the reason why the gradual upshift can be performed is that the high side clutch 8a and the low side clutch 8b are in the slip engagement state. Further, the reason why the motor rotation speed can be maintained is that the vehicle speed (= transmission output rotation speed) increases in the section from time t6 to t7.

  Further, when the motor rotation speed increases from time t7 and reaches the resonance avoidance completion determination rotation speed (> second motor rotation speed) at time t8, the resonance avoidance request flag is cleared. That is, from time t5 to time t7 is a resonance avoidance speed change section that quickly passes through the motor resonance rotational speed region while maintaining the driving force by the slip engagement state of the high side clutch 8a and the low side clutch 8b. Note that by shifting from a down shift to a gradual up shift in the resonance avoidance shift section, the speed ratio before the resonance avoidance shift section and the speed ratio after the resonance avoidance shift section are maintained at the same speed ratio (speed stage). . Since other operations are the same as those of the first embodiment, description thereof is omitted.

Next, the effect will be described.
In the control apparatus for the electric vehicle A3 with the dual clutch transmission according to the third embodiment, the following effects can be obtained.

(8) The transmission is a dual clutch transmission 8 that includes a high-side clutch 8a and a low-side clutch 8b as friction clutches, and switches between a high gear and a low gear.
When it is determined that the resonance avoidance controller (integrated controller 12, FIG. 2) can be avoided by the shift control of the dual clutch transmission 8, the high side clutch 8a and the low side clutch 8b are brought into the slip engagement state, and the high side clutch After downshifting with 8a as the disengagement side and the low side clutch 8b as the engagement side, shift control is performed to shift to an upshift with the high side clutch 8a as the engagement side and the low side clutch 8b as the disengagement side. The motor rotation speed control is performed to maintain the motor rotation speed after passing through the motor resonance rotation speed area and passing through the motor resonance rotation speed area by the upshift (FIG. 11).
Therefore, in addition to the effect of (4), in the case of the resonance avoidance shift control by the dual clutch transmission 8, the shift control of the down shift → up shift is performed by setting the high side clutch 8a and the low side clutch 8b to the slip engagement state. Thus, it is possible to suppress a change in the driving force before and after the resonance avoidance control.

  As mentioned above, although the control apparatus of the electric vehicle of this invention has been demonstrated based on Example 1-3, it is not restricted to these Examples about a concrete structure, Each claim of a claim Design changes and additions are permitted without departing from the spirit of the invention.

  In the first to third embodiments, when the resonance avoidance shift control is performed, an example is shown in which the shift is performed by combining the down shift and the up shift. However, when the resonance avoidance shift control is performed, an example in which the resonance band is passed only by the down shift may be used.

  In the first embodiment, an example in which the automatic transmission 3 is used as a transmission is shown. In the second embodiment, an example in which a continuously variable transmission 7 is used as a transmission is shown. In the third embodiment, a dual clutch transmission 8 is used as a transmission. An example using is shown. However, the transmission is not limited to these transmissions as long as the transmission can perform up-shifting and down-shifting by external control.

  In the first to third embodiments, examples in which the control device of the present invention is applied to an electric vehicle are shown. However, the control device of the present invention can also be applied to a hybrid vehicle having an electric vehicle traveling mode. In short, any electric vehicle including a motor, a friction clutch, and a transmission can be applied to the driving force transmission system.

Cross-reference of related applications

  This application claims priority based on Japanese Patent Application No. 2014-188138 filed with the Japan Patent Office on September 16, 2014, the entire disclosure of which is fully incorporated herein by reference.

Claims (8)

In an electric vehicle equipped with a motor, a friction clutch and a transmission in the driving force transmission system,
A resonance avoidance controller that performs control to avoid the motor operating point due to the motor rotation speed and motor torque of the motor from staying in the resonance region during acceleration;
The resonance avoidance controller, when the motor operating point passes through the resonance region, selects the shift control of the transmission when the driving force is less than a predetermined value, and when the driving force exceeds a predetermined value, Resonance avoidance control for selecting slip control of a friction clutch is executed . In the control device of the electric vehicle according to claim 1,
The resonance avoidance controller, a predetermined value of the travel driving force, when it is assumed that performed the shift control, making the motor speed and the motor torque required boundary value or impossible if the motor can actually output A control device for an electric vehicle. In the control apparatus of the electric vehicle according to claim 2 ,
The resonance avoidance controller sets a motor resonance rotation speed area as a resonance area of the motor rotation speed among resonance areas at the time of acceleration by a motor operating point by the motor rotation speed and motor torque of the motor ,
When the actual rotational speed of the motor increases and reaches the first motor rotational speed before entering the motor resonant rotational speed region, the resonance avoidance control is selected and the selected resonant avoidance control is started. Control device. In the control apparatus of the electric vehicle according to claim 3,
The resonance avoidance controller selects the shift control of the transmission as the resonance avoidance control when it is determined that the traveling driving force is equal to or less than a predetermined value by the boundary value and can be avoided by the shift control of the transmission. And
Downshifting of the transmission is performed by clutch control for reducing the instruction torque to the friction clutch and motor rotation speed control for increasing the motor rotation speed with the transmission input rotation speed crossing the motor resonance rotation speed region as a target rotation speed. An electric vehicle control device characterized by performing assist control. In the control apparatus of the electric vehicle according to claim 3,
The resonance avoidance controller selects the slip control of the friction clutch as the resonance avoidance control when it is determined that the travel driving force exceeds a predetermined value by the boundary value and cannot be avoided by the shift control of the transmission .
Clutch control for maintaining the instruction torque to the friction clutch, and motor rotation speed control for increasing the motor rotation speed with the clutch slip rotation speed crossing the motor resonance rotation speed region as a target rotation speed. A control device for an electric vehicle characterized by performing slip control. In the control apparatus of the electric vehicle according to claim 4,
The transmission is a stepped automatic transmission,
The resonance avoidance controller is determined to be avoided by shifting control of the automatic transmission, the shift control of the automatic transmission Ru is selected, the friction clutch to the slip engagement state, to downshift → upshift In addition to performing the shift control to shift to, the motor rotation speed control is performed to pass the motor resonance rotation speed region during the downshift and maintain the motor rotation speed after passing the motor resonance rotation speed region by the upshift. A control device for an electric vehicle. In the control apparatus of the electric vehicle according to claim 4,
The transmission is a continuously variable transmission,
The resonance avoidance controller, wherein it is determined that can be avoided by shifting control of the continuously variable transmission, wherein the shifting control of the continuously variable transmission Ru is selected, the transmission to shift to the upshift → downshift → upshift In addition to performing control, the motor speed is brought closer to the motor resonance speed area by the first upshift, passes through the motor resonance speed area during the downshift, and passes through the motor resonance speed area by the subsequent upshift. A control device for an electric vehicle characterized by performing motor rotation speed control for maintaining the motor rotation speed. In the control apparatus of the electric vehicle according to claim 4,
The transmission is a dual clutch transmission that includes a high-side clutch and a low-side clutch as friction clutches, and switches between a high gear and a low gear.
The resonance avoidance controller, wherein it is determined that Deyu be avoided in shift control of the Al clutch transmission, said Deyu the shift control of the Al clutch transmission Ru is selected, the high-side clutch and the low-side clutch slip engagement state Shift control for shifting to an upshift with the high side clutch as the engagement side and the low side clutch as the release side after the down shift with the high side clutch as the release side and the low side clutch as the engagement side. A motor speed control that performs motor speed control that passes through the motor resonance speed area during downshifting and maintains the motor speed after passing through the motor resonance speed area by upshifting. apparatus.

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