Vehicle control device

Abstract

To provide a vehicle control device that can reflect the deceleration intention of a driver on the deceleration.SOLUTION: A vehicle 1 that allows the selection of a one-pedal drive mode which performs control to the stop from the acceleration / deceleration of the vehicle 1 by controlling the output torque of a drive motor 4 according to the operation state of an accelerator pedal 61 includes an ECU 6 which corrects the regenerative torque of the drive motor 4 when a change amount of the accelerator pedal 61 per unit time when the driver-requested torque calculated from the operation amount of the accelerator pedal 61 changes to zero is reduced to a prescribed value or greater in a case where the one-pedal drive mode is selected.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a vehicle control device. [Background technology]

[0002] Patent document 1 describes that when calculating the target value of the regenerative braking force during coasting, a reference regenerative braking force is calculated, and then a correction amount according to the vehicle-to-vehicle distance and a correction amount according to the road conditions ahead are calculated, and the maximum of these correction amounts is added to the reference regenerative braking force to correct the target value. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2001-54203 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, as described in Patent Document 1, if the correction amount is calculated based on the distance to the vehicle ahead and the road conditions ahead, the deceleration rate depends on surrounding conditions such as the distance between the vehicles ahead and the road conditions ahead, so it is not possible to reflect the driver's intention to decelerate, and the driver would have to operate the brake pedal.

[0005] SUMMARY OF THE PRESENT DISCLOSURE An object of the present invention is to provide a vehicle control device that can reflect the driver's intention to decelerate in the deceleration rate. [Means for solving the problem]

[0006] In order to solve the above problems, the present invention is a vehicle control device that is installed in a vehicle that can select a one-pedal drive mode in which the output torque of a drive motor is controlled in accordance with the operation state of the accelerator pedal, thereby controlling the vehicle from acceleration / deceleration to stopping, and is equipped with a control unit that causes the drive motor to output regenerative torque when the driver requested torque calculated from the amount of depression of the accelerator pedal becomes zero, and the control unit corrects the regenerative torque of the drive motor when the one-pedal drive mode is selected and the amount of change in the accelerator pedal per unit time when the driver requested torque changes to zero has decreased by more than a predetermined value. Effect of the Invention

[0007] In this way, according to the present invention, the driver's intention to decelerate can be reflected in the deceleration rate. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a schematic diagram of a vehicle control device according to an embodiment of the present invention. [Diagram 2] FIG. 2 shows an example of a map for determining a driver requested torque from an accelerator opening and a vehicle speed in a vehicle control device according to one embodiment of the present invention, where FIG. 2(a) is a map for normal operation, and FIG. 2(b) is a map for one-pedal drive mode. [Diagram 3] FIG. 3 is a diagram showing an example of a map for determining a correction amount from a vehicle distance in a vehicle control device according to an embodiment of the present invention. [Figure 4] FIG. 4 is a block diagram of a control system for calculating a required motor torque in the vehicle control device according to one embodiment of the present invention. [Diagram 5] FIG. 5 is a time chart showing a change in the amount of regenerative power generation due to the regenerative torque correction process of the vehicle control device according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] A vehicle control device according to one embodiment of the present invention is mounted on a vehicle in which a one-pedal drive mode can be selected in which the output torque of the drive motor is controlled in accordance with the operation state of the accelerator pedal, thereby controlling the vehicle from acceleration / deceleration to stopping, and the vehicle control device is equipped with a control unit that causes the drive motor to output regenerative torque when the driver requested torque calculated from the amount of depression of the accelerator pedal becomes zero, and the control unit is configured to correct the regenerative torque of the drive motor when the one-pedal drive mode is selected and the amount of change in the accelerator pedal pressure per unit time when the driver requested torque changes to zero has decreased by more than a predetermined value.

[0010] As a result, the vehicle control device according to the embodiment of the present invention can reflect the driver's intention to decelerate in the deceleration rate. EXAMPLES

[0011] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A vehicle control device according to an embodiment of the present invention will be described in detail below with reference to the drawings.

[0012] In FIG. 1, a vehicle 1 equipped with a vehicle control device according to one embodiment of the present invention is configured to include an engine 2 as an internal combustion engine, a transmission 3 as a gearbox, a drive motor 4, and an ECU (Electronic Control Unit) 6 as a control unit.

[0013] The engine 2 is formed with a plurality of cylinders. In this embodiment, the engine 2 is configured to perform a series of four strokes, consisting of an intake stroke, a compression stroke, an expansion stroke, and an exhaust stroke, for each cylinder. The ignition timing and the amount of fuel injection of the engine 2 are controlled by the ECU 6.

[0014] An air conditioner compressor 5 of an air conditioner (not shown) and an alternator 21 are connected to the engine 2. The air conditioner compressor 5 and the alternator 21 are connected to the crankshaft of the engine 2 via a belt 22 or the like, and are driven by the power output from the crankshaft of the engine 2.

[0015] The alternator 21 generates electric power using the power of the engine 2. The alternator 21 charges an auxiliary battery (not shown) that supplies electric power to an electric load such as an electric component of the vehicle (not shown).

[0016] The transmission 3 changes the speed of the rotation output from the engine 2 and drives drive wheels 10 via a drive shaft 11. The transmission 3 includes a constant mesh type speed change mechanism (not shown) made of a parallel shaft gear mechanism, and an actuator (not shown).

[0017] A dry single-plate clutch 31 is provided between the engine 2 and the transmission 3 as an engagement mechanism. The clutch 31 is in an engaged state in which power transmission between the engine 2 and the transmission 3 is connected, or in a disengaged state in which power transmission between the engine 2 and the transmission 3 is disconnected.

[0018] The drive motor 4 may be connected to any location on the power transmission path from the clutch 31 to the drive wheels 10 so as to be capable of transmitting power.

[0019] In this way, the vehicle 1 constitutes a parallel hybrid system that can use the power of both the engine 2 and the drive motor 4 to drive the vehicle 1, and runs using the power output by at least one of the engine 2 and the drive motor 4.

[0020] The ECU 6 is composed of a computer unit equipped with a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), a flash memory for storing backup data, etc., an input port, and an output port.

[0021] The ROM of this computer unit stores various constants, various maps, and the like, as well as a program for causing the computer unit to function as the ECU 6.

[0022] That is, the CPU executes the programs stored in the ROM using the RAM as a working area, whereby this computer unit functions as the ECU 6 in this embodiment.

[0023] An input port of the ECU 6 is connected to various sensors and switches, such as an accelerator opening sensor 62, a vehicle speed sensor 63, a one-pedal drive mode switch 64, a preceding vehicle detector 65, and a brake stroke sensor 67.

[0024] The accelerator opening sensor 62 detects the opening of the accelerator pedal 61 operated by the driver. The vehicle speed sensor 63 detects the speed of the vehicle 1.

[0025] The one-pedal drive mode switch 64 accepts an operation by the driver and outputs an ON or OFF signal. If an ON signal is output from the one-pedal drive mode switch 64, the ECU 6 uses the one-pedal drive mode in which the vehicle 1 is accelerated and decelerated and stopped by only the operation of the accelerator pedal 61. If an OFF signal is output from the one-pedal drive mode switch 64, the ECU 6 does not use the one-pedal drive mode.

[0026] The preceding vehicle detection unit 65 detects at least the distance to a preceding vehicle traveling in front of the vehicle 1. The preceding vehicle detection unit 65 is composed of, for example, a millimeter wave radar disposed at the front end of the vehicle 1, a camera or a laser radar provided at the top edge of the front windshield, or the like.

[0027] The brake stroke sensor 67 detects the amount of depression of the brake pedal 66 operated by the driver.

[0028] Meanwhile, various control objects including the above-mentioned transmission 3, drive motor 4, air conditioner compressor 5, alternator 21, clutch 31, as well as a starter and injectors (not shown) are connected to the output port of the ECU 6. The starter rotates when power is supplied to rotate the crankshaft of the engine 2, providing the engine 2 with torque at start-up. The injector supplies fuel to the engine 2. The ECU 6 controls the starter and injectors to control the starting and stopping of the engine 2, the output torque, etc.

[0029] Even when the vehicle 1 is driven by the power of the drive motor 4 alone, the ECU 6 rotates the engine 2 when engine rotation elements such as the air conditioner compressor 5 and the alternator 21 require the engine 2 to rotate.

[0030] Times when it is necessary to rotate the engine 2 include, for example, when the air conditioner compressor 5 must be driven due to the operation of the air conditioner, when the alternator 21 must be driven due to a drop in the SOC (State Of Charge) of the auxiliary battery, when brake negative pressure must be secured, and when the cooling water temperature of the engine 2 must be secured.

[0031] The ECU 6 rotates the engine 2, for example, when a predetermined engine rotation condition is satisfied. The engine rotation condition is, for example, that the air conditioner compressor 5 must be driven, that the SOC of the auxiliary battery is equal to or lower than a predetermined value, that the brake negative pressure is equal to or lower than a predetermined pressure, that the coolant temperature of the engine 2 is equal to or lower than a predetermined temperature, etc. In other words, the factors that require the rotation of the engine 2 are the engine rotation conditions.

[0032] When the one-pedal drive mode is selected by the one-pedal drive mode switch 64, the ECU 6 controls the power of the engine 2 and the drive motor 4, and controls the clutch 31, depending on the operation state of the accelerator pedal 61, thereby controlling the acceleration / deceleration and stopping of the vehicle 1.

[0033] The ECU 6 determines a driver requested torque based on the accelerator opening and the vehicle speed. The ECU 6 determines the driver requested torque according to a map shown in FIG.

[0034] Figure 2(a) is a map for normal driving, not in one-pedal drive mode, and Figure 2(b) is a map for driving in one-pedal drive mode.

[0035] In the region marked "positive torque" in the figure, the ECU 6 causes the drive motor 4 to output a drive torque. In the region marked "negative torque" in the figure, the ECU 6 causes the drive motor 4 to output a regenerative torque as a braking torque.

[0036] When one-pedal drive mode is selected, the ECU 6 corrects the regenerative torque of the drive motor 4 if the amount of change in the accelerator pedal 61 per unit time when the driver required torque calculated from the amount of operation of the accelerator pedal 61 changes to zero decreases by more than a predetermined value.

[0037] The point where the driver requested torque becomes zero is on the straight line that is the boundary between the "positive torque" region and the "negative torque" region in the map of FIG.

[0038] The amount of change in accelerator pedal 61 is a direction in which the accelerator pedal 61 is released (a direction in which the accelerator opening becomes zero), and when the amount of change in the decreasing direction per unit time is equal to or greater than a predetermined value, the regenerative torque of drive motor 4 is corrected. In other words, when the speed at which the driver releases accelerator pedal 61 is equal to or greater than a predetermined speed, the regenerative torque of drive motor 4 is corrected to reflect the driver's intention to decelerate.

[0039] The change amount of the accelerator pedal 61 here is the change amount during a period (for example, 1 second or 2 seconds) going back a predetermined time from when the driver required torque became zero. By referring to this period, it is possible to reflect the driver's final intention to decelerate.

[0040] When one-pedal drive mode is selected, if the amount of change in accelerator pedal 61 per unit time when the driver required torque calculated from the amount of operation of accelerator pedal 61 changes to zero is less than a predetermined value, ECU 6 does not correct the regenerative torque of drive motor 4.

[0041] When the one-pedal drive mode is selected, the ECU 6 corrects the regenerative torque of the drive motor 4 based on the vehicle distance to the preceding vehicle detected by the preceding vehicle detection unit 65 when the driver requested torque calculated from the amount of operation of the accelerator pedal 61 changes to zero.

[0042] The ECU 6 determines the amount of correction, for example, using a map as shown in Fig. 3. As shown in Fig. 3, the ECU 6 performs negative correction to reduce the regenerative torque of the drive motor 4 when the inter-vehicle distance is longer than a predetermined distance.

[0043] When the ECU 6 detects that the brake pedal 66 is depressed while correcting the regenerative torque of the drive motor 4, the ECU 6 sets the correction amount to zero. The ECU 6 may be configured to gradually decrease the correction amount.

[0044] If the amount of operation of the brake pedal 66 is equal to or greater than a predetermined value, it may be determined that sudden braking has occurred, and the correction may be continued for the period during which sudden braking occurs. In this way, it is possible to prevent braking failure due to a decrease in deceleration.

[0045] FIG. 4 is a block diagram of a control system for calculating the motor required torque in the vehicle control device according to this embodiment.

[0046] The braking force correction determination unit 71 determines whether or not to correct the regenerative torque of the drive motor 4 based on the accelerator opening.

[0047] A driver requested torque calculation unit 72 calculates the torque requested of the drive motor 4 from the accelerator opening and the vehicle speed.

[0048] The target deceleration calculation unit 73 calculates a target deceleration based on the distance to the preceding vehicle, the relative speed to the preceding vehicle, and the vehicle speed of the vehicle 1 .

[0049] A braking force correction amount calculation unit 74 calculates a correction amount for the regenerative torque of the drive motor 4 from the target deceleration calculated by the target deceleration calculation unit 73 and the vehicle speed.

[0050] The correction execution unit 75 corrects the motor required torque calculated by the driver required torque calculation unit 72 with the correction amount calculated by the braking force correction amount calculation unit 74 .

[0051] Based on the judgment result of the braking force correction judgment unit 71, the motor required torque selection unit 76 outputs either the motor required torque calculated by the driver required torque calculation unit 72 or the motor required torque corrected by the correction execution unit 75 as the motor required torque.

[0052] The operation of the regenerative torque correction process of the vehicle control device according to this embodiment configured as above will be described with reference to Fig. 5. Note that the "regenerative power generation amount" in the figure is the amount of power generated by the regenerative torque of the drive motor 4, and is equal to the amount of regenerative torque.

[0053] At time t1, accelerator pedal 61 begins to be released, and at time t2, when the accelerator opening becomes zero, regenerative torque is output from drive motor 4 and the amount of regenerative power generation increases. Here, the amount of change in accelerator pedal 61 per unit time is a decrease less than a predetermined value, so no correction of the regenerative torque is performed.

[0054] At time t3, when the accelerator pedal 61 is depressed, the regenerative torque of the drive motor 4 becomes zero, and the amount of regenerative power generation also becomes zero.

[0055] At time t4, the accelerator pedal 61 begins to be released, and at time t5, when the accelerator opening becomes zero, a regenerative torque is output from the drive motor 4, and the amount of regenerative power generation increases. At this time, the amount of change in the accelerator pedal 61 per unit time has decreased by a predetermined value or more, so a correction amount is calculated based on the vehicle speed and the distance to the preceding vehicle, the correction amount is corrected from the normal regenerative torque, and the amount of regenerative power generation also increases by the corrected amount (indicated by A in the figure).

[0056] At time t6, when the brake pedal 66 is depressed, the correction amount is gradually reduced to zero, and at time t7, when the brake pedal 66 is released and the accelerator pedal 61 is depressed, the regenerative torque disappears and the amount of regenerative power generation also becomes zero, and at time t8, when the accelerator opening degree becomes constant, the state is maintained.

[0057] Thus, in this embodiment, when one-pedal drive mode is selected, the ECU 6 corrects the regenerative torque of the drive motor 4 if the amount of change in the accelerator pedal 61 per unit time when the driver required torque calculated from the amount of operation of the accelerator pedal 61 changes to zero decreases by more than a predetermined value.

[0058] As a result, if the amount of change in accelerator pedal 61 operation per unit time when the driver required torque changes to zero has decreased by a predetermined value or more, the regenerative torque of the drive motor 4 is corrected. Therefore, the driver's intention can be more appropriately reflected in the deceleration based on the amount of change in accelerator pedal 61 operation, enabling more appropriate one-pedal control.

[0059] In addition, the ECU 6 does not correct the regenerative torque of the drive motor 4 if the amount of change in the accelerator pedal 61 per unit time when the driver requested torque calculated from the amount of operation of the accelerator pedal 61 changes to zero is less than a predetermined value.

[0060] As a result, if the amount of change in accelerator pedal 61 per unit time when the driver required torque changes to zero is less than a predetermined value, the regenerative torque of the drive motor 4 is not corrected. Therefore, when it is determined that the driver does not have a sufficient intention to decelerate, normal regenerative braking is performed, enabling more suitable one-pedal control.

[0061] Furthermore, the ECU 6 corrects the regenerative torque of the drive motor 4 based on the distance to the preceding vehicle when the driver's requested torque calculated from the operation amount of the accelerator pedal 61 changes to zero.

[0062] As a result, the regenerative torque of the drive motor 4 is corrected based on the distance from the preceding vehicle when the driver required torque changes to zero. By calculating the correction amount based on the distance between the vehicles at the timing when the driver required torque changes to zero, the driver's intention to decelerate based on the distance between the vehicles can be appropriately reflected, and the driver's intention to decelerate can be more appropriately reflected.

[0063] Furthermore, when the ECU 6 detects that the brake pedal 66 is depressed while correcting the regenerative torque of the drive motor 4, the ECU 6 sets the correction amount to zero.

[0064] As a result, when the regenerative torque of the drive motor 4 is being corrected, if depression of the brake pedal 66 is detected, the correction amount is set to zero. Therefore, when the brake pedal 66, which appropriately reflects the driver's intention to decelerate, is operated, the correction amount is set to zero in order to give priority to deceleration by the brake pedal 66, so that the driver's intention to decelerate can be more appropriately reflected.

[0065] In this embodiment, an example has been described in which the ECU 6 performs various determinations and calculations based on various sensor information, but the present invention is not limited to this. The vehicle 1 may be provided with a communication unit capable of communicating with an external device such as an external server, and various determinations and calculations may be performed by the external device based on the detection information of the various sensors transmitted from the communication unit. The determination results and calculation results may be received by the communication unit, and various controls may be performed using the received determination results and calculation results.

[0066] Although an embodiment of the invention has been disclosed, it will be apparent to one of ordinary skill in the art that modifications may be made therein without departing from the spirit and scope of the invention, and it is intended that all such modifications and equivalents be included in the following claims. [Explanation of symbols]

[0067] 1 vehicle 4 Drive motor 6 ECU (control unit) 61 Accelerator pedal 62 Accelerator opening sensor 63 Vehicle speed sensor 64 One-pedal drive mode switch 65 Leading vehicle detection unit 66 Brake pedal 67 Brake stroke sensor 71 Braking force correction determination section 72 Driver required torque calculation unit 73 Target deceleration calculation section 74 Braking force correction amount calculation section 75 Correction Execution Unit 76 Motor required torque selection section

Claims

1. A vehicle control device is installed in a vehicle capable of selecting a one-pedal drive mode in which the output torque of a drive motor is controlled in accordance with an operation state of an accelerator pedal to control the vehicle from acceleration / deceleration to stopping, and the vehicle control device includes a control unit that causes the drive motor to output a regenerative torque when a driver request torque calculated from an amount of depression of the accelerator pedal becomes zero, the control unit comprising: The control unit is a vehicle control device that corrects the regenerative torque of the drive motor when the one-pedal drive mode is selected and the amount of change in the accelerator pedal pressure per unit time when the driver requested torque changes to zero decreases by more than a predetermined value.

2. The vehicle control device according to claim 1 , wherein the control unit does not correct the regenerative torque of the drive motor when the amount of change in the accelerator pedal pressure per unit time is less than a predetermined value.

3. a preceding vehicle detection unit that detects at least a distance between the host vehicle and a preceding vehicle traveling ahead of the host vehicle; 3. The vehicle control device according to claim 1, wherein the control unit corrects the regenerative torque of the drive motor based on a distance from the preceding vehicle when the driver requested torque changes to zero.

4. 3. The vehicle control device according to claim 1, wherein the control unit sets a correction amount of the regenerative torque of the drive motor to zero when a brake pedal of the vehicle is depressed.

5. The vehicle control device according to claim 3 , wherein the control unit sets a correction amount of the regenerative torque of the drive motor to zero when a brake pedal of the vehicle is depressed.

Images