Vehicle control device

Abstract

To provide a vehicle control device capable of making it unnecessary to perform troublesome operation of placing a foot on a brake pedal immediately after accelerator pedal operation in regenerative brake control in the case of turning at a crossing.SOLUTION: An electronic control device 90 comprises: a crossing determination section 92 for determining whether or not a vehicle 10 is turning right or left at a crossing CR and whether or not the vehicle 10 has exited the crossing CR; and a regenerative control section 94 for performing control to shift to a normal regenerative mode when it is determined by the crossing determination section 92 that the vehicle 10 is turning right or left at the crossing CR, during traveling in a strong regenerative mode, and to shift to the strong regenerative mode when it is determined that the vehicle 10 has exited the crossing CR. Thereby, regenerative brake force in the normal regenerative mode is obtained while the vehicle 10 is turning right or left at the crossing CR, so that deceleration does not become significant when an accelerator is off, and it is possible to keep a foot on a brake pedal. As a result, it becomes unnecessary to perform operation of placing the foot on the brake pedal immediately after accelerator pedal operation.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a control device for a vehicle that obtains regenerative braking force by regenerating a power source, that is, an electric motor. [Background technology]

[0002] In vehicles that obtain regenerative braking force through regeneration by an electric motor, which is a power source, technology has been disclosed that allows the driver to select the strength of the regenerative braking force. For example, a regenerative brake control device is described in Patent Document 1. In recent years, vehicles have been provided that have a function (hereinafter referred to as a strong regenerative mode) that increases the strength of the regenerative braking force beyond normal, allowing acceleration and deceleration by operating only the accelerator pedal. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-29416 Summary of the Invention [Problem to be solved by the invention]

[0004] When turning at an intersection while driving in the strong regeneration mode, you want to keep your foot on the brake pedal so that you can stop quickly at the intersection, but in the strong regeneration mode, deceleration is large when you release the accelerator, so you need to keep your foot pressed down on the accelerator pedal.In such a situation, while turning, you need to immediately switch from operating the accelerator pedal to maintain vehicle speed to placing your foot on the brake pedal, which is a cumbersome operation.

[0005] The present invention has been made in light of the above circumstances, and its purpose is to provide a vehicle control device that eliminates the need for the troublesome operation of immediately placing the foot on the brake pedal after operating the accelerator pedal when performing regenerative braking control when turning at an intersection. [Means for solving the problem]

[0006] The gist of the present invention is (a) a control device for a vehicle that obtains regenerative braking force through regeneration of an electric motor that is a power source, (b) a regenerative brake control that controls the regenerative braking force, which includes a normal regenerative mode and a strong regenerative mode that makes the regenerative braking force greater than that in the normal regenerative mode, (c) an intersection determination unit that determines whether the vehicle is turning right or left at an intersection and whether the vehicle has exited the intersection, and (d) a regenerative control unit that, while traveling in the strong regenerative mode, if the intersection determination unit determines that the vehicle is turning right or left at the intersection, controls the vehicle to transition to the normal regenerative mode, and if it determines that the vehicle has exited the intersection, controls the vehicle to transition to the strong regenerative mode. [Effects of the Invention]

[0007] According to the present invention, the control device includes an intersection determination unit that determines whether the vehicle is turning right or left at the intersection and whether it has exited the intersection, and a regeneration control unit that performs control to transition to the normal regeneration mode when the intersection determination unit determines that the vehicle is turning right or left at the intersection while the vehicle is traveling in the strong regeneration mode, and to transition to the strong regeneration mode when the intersection determination unit determines that the vehicle has exited the intersection. As a result, while the vehicle is turning right or left at the intersection, the regenerative braking force is in the normal regeneration mode, so that deceleration does not increase when the accelerator is released, and the driver can keep his or her foot on the brake pedal. Therefore, there is no need to immediately place his or her foot on the brake pedal after operating the accelerator pedal. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a diagram illustrating a schematic configuration of a vehicle to which the present invention is applied, and is also a diagram illustrating main parts of control functions and control systems for various controls in the vehicle. [Figure 2]1 is a flowchart illustrating the main control operations of the electronic control device, and is a flowchart illustrating the control operations of regenerative brake control when turning right or left at an intersection while traveling in a strong regenerative mode. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. [Example]

[0010] FIG. 1 is a diagram illustrating the schematic configuration of a hybrid vehicle (hereinafter referred to as vehicle) 10 to which the present invention is applied, and also illustrates the main parts of a control system for various controls in the vehicle 10. In FIG. 1, the vehicle 10 is equipped with an engine 12, a first electric motor MG1, and a second electric motor MG2. The vehicle 10 also is equipped with drive wheels 14 and a power transmission device 16 provided in a power transmission path between the engine 12 and the drive wheels 14. The vehicle 10 is a hybrid vehicle equipped with the engine 12 and the second electric motor MG2, which function as a power source. The second electric motor MG2 corresponds to the "electric motor" in the present invention.

[0011] The engine 12 is a known internal combustion engine. An engine control device 50 provided in the vehicle 10 is controlled by an electronic control device 90 (described later), whereby the engine torque Te of the engine 12 is controlled.

[0012] The first electric motor MG1 and the second electric motor MG2 are each a rotating electric machine, a so-called motor generator. The first electric motor MG1 and the second electric motor MG2 are each connected to a battery 54 provided in the vehicle 10 via an inverter 52 provided in the vehicle 10. The battery 54 is an electricity storage device that supplies and receives electric power to and from each of the first electric motor MG1 and the second electric motor MG2. The inverter 52 of the first electric motor MG1 and the second electric motor MG2 is controlled by an electronic control device 90 described later, thereby controlling the MG1 torque Tg of the first electric motor MG1 and the MG2 torque Tm of the second electric motor MG2. The MG1 torque Tg is controlled for differential control of the planetary gear set 40 described later, and the MG2 torque Tm is controlled to obtain drive torque for the vehicle 10 and regenerative torque (regenerative braking force) for regenerating kinetic energy of the vehicle 10.

[0013] The power transmission device 16 includes, within a case 18, a damper 20, an input shaft 22 connected to the crankshaft 12a of the engine 12 via the damper 20, a transmission unit 24 connected to the input shaft 22, a compound gear 26, a driven gear 28, a driven shaft 30, a final gear 32, a differential gear 34, a reduction gear 36, a rotor shaft RSmg1 connected to the rotor of the first electric motor MG1, and a rotor shaft RSmg2 connected to the rotor of the second electric motor MG2. The power transmission device 16 also includes a pair of drive shafts 38 connected to the differential gear 34.

[0014] The compound gear 26 is a hollow cylindrical output rotation member. A drive gear 26a is integrally provided on one axial end of the outer circumferential surface of the compound gear 26. The drive gear 26a meshes with a driven gear 28 and is connected to the drive wheels 14 so as to be able to transmit power.

[0015] The driven shaft 30 fixes the driven gear 28 and the final gear 32 so that they cannot rotate relative to each other. The final gear 32 meshes with a differential ring gear 34a of the differential gear 34. The reduction gear 36 meshes with the driven gear 28 and is connected to the rotor shaft RSmg2. The second electric motor MG2 is connected to the drive wheels 14 so as to be able to transmit power, and is also connected to the drive gear 26a so as to be able to transmit power.

[0016] The transmission unit 24 includes a first electric motor MG1 and a planetary gear set 40. The planetary gear set 40 is a differential mechanism and is a known single-pinion planetary gear set including a sun gear S, a carrier CA, a ring gear R, and a plurality of pinions P. The sun gear S is connected to the rotor shaft RSmg1, and is connected to the first electric motor MG1 so as to be able to transmit power. The carrier CA is connected to the input shaft 22 so as to be able to transmit power, and is connected to the engine 12 so as to be able to transmit power. Each pinion P is supported by the carrier CA so as to be able to rotate and revolve. The ring gear R is integrally provided on a part of the inner circumferential surface of the compound gear 26. The ring gear R meshes with the sun gear S via the pinion P. The planetary gear set 40 is a power split mechanism that mechanically splits the power of the engine 12 input to the carrier CA between the first electric motor MG1 and the drive gear 26a. The transmission unit 24 is a known electric continuously variable transmission in which the differential state of the planetary gear device 40 is controlled by controlling the operating state of the first electric motor MG1.

[0017] In the transmission unit 24, MG1 torque Tg, which is a reaction torque of the negative torque generated by the first electric motor MG1 in response to the positive engine torque Te input to the carrier CA, is input to the sun gear S. As a result, a positive direct engine torque Td (= Te / (1+ρ) = -(1 / ρ) × Tg) appears in the ring gear R during forward rotation. The combined torque of the direct engine torque Td and the MG2 torque Tm is transmitted to the drive wheels 14 as drive torque. At this time, the electric power generated by the first electric motor MG1 is supplied to the battery 54 and the second electric motor MG2. The above "ρ" is the gear ratio of the planetary gear set 40 (= number of teeth of the sun gear / number of teeth of the ring gear).

[0018] The vehicle 10 is equipped with an electronic control unit 90 that includes a control device for the vehicle 10. The electronic control unit 90 includes a so-called microcomputer, and performs various controls for the vehicle 10.

[0019] The electronic control device 90 is supplied with various signals (e.g., engine rotation speed Ne, output rotation speed No which is the rotation speed of the driven gear 28 corresponding to the vehicle speed V, MG1 rotation speed Ng, MG2 rotation speed Nm, steering wheel angle θsw, accelerator opening pap which is the amount of accelerator operation by the driver, regeneration mode signal Kmd, and blinker signal Wkr) based on detection values ​​from various sensors provided on the vehicle 10 (e.g., engine rotation speed sensor 70, output rotation speed sensor 72, MG1 rotation speed sensor 74, MG2 rotation speed sensor 76, steering angle sensor 78, accelerator opening sensor 80, regeneration mode setting switch 84, and blinker switch 86).

[0020] The regeneration mode setting switch 84 is a switch for selecting a mode of regenerative braking control that controls regenerative braking force, and the driver selects one of multiple regeneration modes that are preset for the strength of regenerative braking force while driving. The regeneration modes include, for example, a normal regeneration mode that is the initial setting, and a mode (hereinafter referred to as a strong regeneration mode) in which the regenerative braking force is stronger than in the normal regeneration mode and acceleration and deceleration can be performed by operating only the accelerator pedal. When the regeneration mode setting switch 84 is operated, a regeneration mode signal Kmd that selects either the normal regeneration mode or the strong regeneration mode is supplied to the electronic control unit 90.

[0021] The winker switch 86 is operated by the driver when turning right or left of the vehicle 10. A winker signal Wkr indicating a right or left turn is turned ON by the driver's operation, and after the right or left turn is completed, the winker signal Wkr is turned OFF when the steering wheel angle θsw of the steering wheel returns to within a predetermined value.

[0022] The electronic control device 90 outputs various command signals (for example, an engine control command signal Se, an MG control command signal Smg, etc.) to each device provided in the vehicle 10 (for example, the engine control device 50, the inverter 52, etc.).

[0023] The electronic control unit 90 functionally comprises an intersection determination unit 92 and a regeneration control unit 94 .

[0024] The intersection determination unit 92 determines whether the vehicle 10 is turning right or left at an intersection CR, and whether the vehicle 10 has exited the intersection CR.

[0025] The regenerative control unit 94 controls the regenerative braking force obtained by regeneration of the second electric motor MG2, i.e., performs regenerative braking control. The regenerative control unit 94 calculates the regenerative braking force required for the vehicle 10 based on changes in the driver's accelerator pedal position pap, the vehicle speed V, and the regenerative mode selected by the driver (either normal regenerative mode or strong regenerative mode), and controls the MG2 torque Tm of the second electric motor MG2 so as to achieve the required regenerative braking force. Furthermore, when the vehicle 10 is turning right or left at an intersection CR while traveling in the strong regenerative mode, the regenerative control unit 94 performs a control operation described later in FIG. 2.

[0026] Figure 2 is a flowchart explaining the control operation of the regenerative braking control of the electronic control unit 90, where Figure 2(a) shows the flowchart when turning right or left at an intersection CR, and Figure 2(b) shows the flowchart when leaving the intersection CR, and each is executed repeatedly, for example, while the vehicle 10 is traveling in strong regenerative mode.

[0027] 2(a), which shows the control operation when turning right or left at an intersection CR, first, in step S1 (hereinafter, "step" will be omitted) corresponding to the function of the intersection determination unit 92, it is determined whether the vehicle 10 is turning right or left at the intersection CR. If the determination in S1 is negative, this routine is terminated. The determination in S1 is made based on whether all of the conditions (see balloon), such as the vehicle speed V being 20 km / h or less and the turn signal signal Wkr being ON, are met. If all of the conditions are met, the result is affirmative, and if not, the result is negative.

[0028] If the determination in S1 is positive, the regeneration mode is shifted to the normal regeneration mode in S2, which corresponds to the function of the regeneration control unit 94, and this routine is then terminated.

[0029] 2(b), which shows the control operation when exiting an intersection CR, first, in step S10 (hereinafter, "step" will be omitted) corresponding to the function of the intersection determination unit 92, it is determined whether the vehicle 10 has exited the intersection CR. If the determination in S10 is negative, this routine is terminated. The determination in S10 is made based on whether all of the following conditions (see balloons) are met: the absolute value of the steering wheel angle θsw is 6° or less, the accelerator opening pap is 10% or more, the turn signal signal Wkr is OFF, etc. If all of the conditions are met, the result is affirmative; if not, the result is negative.

[0030] If the determination in S10 is affirmative, the regeneration mode is shifted to the strong regeneration mode in S20, which corresponds to the function of the regeneration control unit 94, and this routine is then terminated.

[0031] As described above, the electronic control device 90 of this embodiment includes an intersection determination unit 92 that determines whether the vehicle 10 is turning right or left at an intersection CR and whether it has exited the intersection CR, and a regeneration control unit 94 that, while traveling in the strong regeneration mode, transitions to the normal regeneration mode if the intersection determination unit 92 determines that the vehicle 10 is turning right or left at the intersection CR, and transitions to the strong regeneration mode if it determines that the vehicle 10 has exited the intersection CR. As a result, while the vehicle 10 is turning right or left at the intersection CR, the regenerative braking force is in the normal regeneration mode, so that deceleration is not large when the accelerator is released, and the driver can keep his or her foot on the brake pedal. Therefore, it is not necessary to immediately place his or her foot on the brake pedal after operating the accelerator pedal.

[0032] Although the embodiments of the present invention have been described in detail above with reference to the drawings, the present invention can also be applied to other embodiments.

[0033] For example, in the above-described embodiment, the vehicle 10 was a hybrid vehicle equipped with an engine 12, a first electric motor MG1, and a second electric motor MG2, but the present invention can be applied to any electric vehicle that performs regenerative braking control using electric motors, regardless of the number or configuration of the electric motors installed.

[0034] It should be noted that the above is merely one embodiment, and the present invention can be embodied in various forms with various modifications and improvements based on the knowledge of those skilled in the art. [Explanation of symbols]

[0035] 10: Vehicle 90: Electronic control unit (control unit) 92: Intersection determination unit 94: Regeneration control unit CR: Intersection MG2: Second electric motor (electric motor)

Claims

[Claim 1] A control device for a vehicle that obtains regenerative braking force by regenerating an electric motor that is a power source, The regenerative brake control for controlling the regenerative brake force includes a normal regenerative mode and a strong regenerative mode in which the regenerative brake force is made larger than that in the normal regenerative mode, an intersection determination unit that determines whether the vehicle is turning right or left at an intersection and whether the vehicle has exited the intersection; a regeneration control unit that performs control to transition to the normal regeneration mode when the intersection determination unit determines that the vehicle is turning right or left at the intersection while traveling in the strong regeneration mode, and to transition to the strong regeneration mode when the intersection determination unit determines that the vehicle has exited the intersection. A vehicle control device comprising:

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