JP2017081355A - Vehicle travel control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicle travel control device which can further enhance a fuel consumption.SOLUTION: A vehicle travel control device has: road information acquisition units (31, 32) for acquiring road information; an equal deceleration control estimation unit (41) for estimating an equal deceleration fluctuation chart of a deceleration or a driving force on the basis of the road information; an equal time calculation unit (42) for calculating a first equally divided time which is a time from deceleration control start time until an integral value of the deceleration or the driving force is equally divided; an unequal deceleration control determination unit (43) which determines an unequal deceleration fluctuation chart of a deceleration or a driving force on the basis of road information so that a second equally divided time, which is a time from deceleration control start time until an integral value at an unequal deceleration time is equally divided, is later than the first equally divided time; a deceleration control unit (13) which controls the deceleration of a vehicle on the basis of the unequal deceleration fluctuation chart; and a regenerative control unit (23) for charging a battery on the basis of the unequal deceleration fluctuation chart.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a vehicle travel control device, and more particularly to a technique for controlling a deceleration state of a vehicle regardless of a road gradient.

  Conventionally, for the purpose of improving fuel consumption and exhaust gas performance, a hybrid electric vehicle including an engine and a motor as a driving power source has been widespread. In this type of hybrid electric vehicle, in recent years, control for automatically accelerating / decelerating the vehicle speed without depending on driver control is known for the purpose of further improving fuel efficiency. As such a control method, there are coast running on a downhill road of automatic cruise control, and adaptive cruise control control.

  For example, Patent Document 1 discloses a technique related to coasting on a downhill road with auto-cruise control. In particular, in Patent Document 1, it is possible to maintain an appropriate inter-vehicle distance with a succeeding vehicle without depending on a driver's operation during execution of range expansion coast traveling control in which the vehicle speed range of auto cruise control is expanded. A control device is disclosed.

JP2015-116871A

  However, although the problems of environmental impact caused by automobiles have been pointed out in the past, in recent years there has been a demand for further reduction of environmental impact in various fields. It becomes important. In particular, from the viewpoint of reducing the environmental load, more efficient energy management is required, and it is considered that there is sufficient room for further study on fuel efficiency improvement.

  The present invention has been made to solve such problems, and an object of the present invention is to provide a vehicle travel control device capable of further improving fuel consumption.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following aspects or application examples.

  The travel control device for a vehicle according to this application example includes a road information acquisition unit that acquires road information related to a predetermined route ahead of the vehicle, and the vehicle moves from the first vehicle speed to the second on the predetermined route based on the road information. An equal deceleration control estimator for estimating a deceleration or an equal deceleration fluctuation chart of driving force required when decelerating to a vehicle speed at a predetermined time in a predetermined time, and the deceleration in the equal deceleration fluctuation chart of the deceleration Or an integral value of the driving force in the constant deceleration correction chart in which the driving force at the first vehicle speed is corrected to zero, and the integrated value is calculated from the deceleration control start time. Based on the road information, the vehicle is unequally decelerated from the first vehicle speed to the second vehicle speed on the predetermined route based on the road information. Integrating the deceleration at the time of unequal deceleration in the unequal deceleration variation chart of deceleration from the deceleration control start time The integral value of the driving force during unequal deceleration in the unequal deceleration correction chart in which the driving force at the first vehicle speed is corrected to zero from the value or deceleration control start time An unequal deceleration control deciding unit for deciding that the second equal time, which is the time until the second time, is slower than the first equal time, and the braking device for the vehicle based on the unequal deceleration fluctuation chart A deceleration control unit that controls the deceleration of the vehicle and a regeneration control unit that regeneratively controls the motor of the vehicle based on the unequal deceleration fluctuation chart and charges the battery of the vehicle. is there.

  According to the present invention using the above means, the fuel consumption can be further improved, and the environmental load on the vehicle can be sufficiently reduced.

1 is a schematic configuration diagram of a hybrid vehicle equipped with a travel control device according to an embodiment of the present invention. It is a control flow which shows control of the hybrid vehicle by the traveling control apparatus which concerns on one Embodiment of this invention. It is a figure which shows the equal deceleration fluctuation | variation chart regarding an acceleration (deceleration), and an unequal deceleration fluctuation | variation chart. It is a figure which shows the equal deceleration fluctuation | variation chart regarding a driving force, and an unequal deceleration fluctuation | variation chart. It is a simulation result which shows the change of the vehicle speed in equal deceleration and unequal deceleration. It is a simulation result which shows the movement distance in equal deceleration and unequal deceleration.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a schematic configuration diagram of a hybrid vehicle equipped with a control device according to an embodiment of the present invention, which will be described with reference to FIG.

  The hybrid vehicle 1 is configured as a so-called parallel type hybrid system. In the following description, the hybrid vehicle 1 is also simply referred to as the vehicle 1.

  A vehicle 1 is equipped with a diesel engine (hereinafter referred to as an engine) 2 as a driving power source and a motor 3 (electric motor) that can also operate as a generator. A clutch 4 is connected to the output shaft of the engine 2, and an input side of the automatic transmission 5 is connected to the clutch 4 via a rotating shaft of the motor 3. A differential device 7 is connected to the output side of the automatic transmission 5 via a propeller shaft 6, and left and right drive wheels 9 are connected to the differential device 7 via a drive shaft 8.

  The automatic transmission 5 automates the connection / disconnection operation of the clutch 4 and the switching operation of the shift stage based on a general manual transmission. In this embodiment, the automatic transmission 5 has a shift stage of 12 forward speeds and 1 reverse speed. ing. Of course, the configuration of the automatic transmission 5 is not limited to this, and can be arbitrarily changed. For example, the automatic transmission 5 may be embodied as a manual transmission, or a so-called dual clutch type automatic transmission having two power transmission systems. It may be embodied as a transmission.

  Specifically, the motor 3 is a synchronous generator motor including a rotor on which a permanent magnet is attached and a stator on which a three-phase coil is wound. That is, the motor 3 can transmit the driving force to the automatic transmission 5 instead of the engine 2, and further generates electric power by driving the engine 2 or reverse driving from the driving wheel 9 side. For example, when the vehicle 1 decelerates or travels on a downhill road, the motor 3 operates as a generator by reverse driving from the drive wheel 9 side (regenerative control). The motor 3 is connected to the power conversion device 10 via a predetermined wiring.

  The power conversion device 10 includes a general inverter and a converter, and is connected to the battery 11 through predetermined wiring. That is, the power conversion device 10 is electrically connected to the motor 3 and the battery 11. Therefore, the power conversion device 10 can convert DC power supplied from the battery 11 into AC power and supply it to the motor 3, and can rectify AC power supplied from the motor 3 and supply it to the battery 11. is there.

  The driving force generated by the motor 3 is transmitted to the driving wheel 9 side regardless of the connection / disconnection state of the clutch 4, whereas the driving force generated by the engine 2 is on the driving wheel 9 side only when the clutch 4 is connected. Is transmitted to. Therefore, when the clutch 4 is disengaged, the positive or negative driving force generated by the motor 3 as described above is transmitted to the driving wheel 9 side, and the vehicle 1 travels. When the clutch 4 is connected, the driving force of the engine 2 and the motor 3 is transmitted to the driving wheel 9 side, or only the driving force of the engine 2 is transmitted to the driving wheel 9 side, and the vehicle 1 travels.

  The vehicle ECU 13 is a control circuit for integrated control of the entire vehicle. For this purpose, the vehicle ECU 13 includes an accelerator sensor 15 that detects an operation amount θacc of the accelerator pedal 14, a brake switch 17 that detects a depression operation of the brake pedal 16, a vehicle speed sensor 18 that detects a speed (vehicle speed) V of the vehicle 1, an engine. Various sensors and switches such as an engine rotational speed sensor 19 for detecting the rotational speed Ne of the motor 2 and a motor rotational speed sensor 20 for detecting the rotational speed Nm of the motor 3 are connected.

  The vehicle ECU 13 is connected to an actuator (not shown) for connecting / disconnecting the clutch 4 and an actuator for shifting the automatic transmission 5, and controls the engine ECU 22 for engine control and the power converter 10. For this purpose, a power conversion ECU 23 and a battery ECU 24 that manages the battery 11 are connected.

  Further, a navigation device 31 and a communication device 32 are connected to the vehicle ECU 13. The navigation device 31 stores map information including road curves, gradients, and the like in advance in its own storage area, and sequentially receives GPS information via an antenna while the vehicle 1 is traveling, so that the vehicle on the map Identify the location. Further, the communication device 32 performs road-to-vehicle communication with a roadside communication system of a data center installed on the roadside, and performs vehicle-to-vehicle communication with other vehicles traveling around. Examples of communication targets include map information not owned by the vehicle, road information (road curves and gradients, etc.), traffic information (congestion information, accident information, construction information, etc.), or local information (tourist spot information, etc.) The communication device 32 acquires such information from the roadside communication system and other vehicles, or conversely supplies the information to other vehicles. That is, road information related to a predetermined route (route to be traveled) in front of the vehicle 1 is acquired from at least one of the navigation device 31 and the communication device 32. In the present embodiment, the navigation device 31 or the communication device 32, or both of these devices function as a road information acquisition unit, and road information is supplied to the vehicle ECU 13 from these devices. Here, the road information includes at least the gradient and length of the predetermined route.

  The vehicle ECU 13 is also connected to various braking devices 33 (for example, a retarder, an engine compression release brake, an exhaust brake, etc.) equipped on the vehicle 1. The vehicle ECU 13 arbitrarily drives and controls these braking devices 33 to apply a braking force to the traveling vehicle 1. That is, in the present embodiment, the vehicle ECU 13 functions as a deceleration control unit.

  The vehicle ECU 13 calculates a required torque necessary for the vehicle 1 to travel based on the accelerator operation amount θacc by the driver, and selects a travel mode of the vehicle 1 based on the required torque, the SOC of the battery 11, and the like. In this embodiment, an E / G mode that uses only the driving force of the engine 2, an EV mode that uses only the driving force of the motor 3, and an HEV mode that uses both the driving force of the engine 2 and the motor 3 are set as the traveling mode. The vehicle ECU 13 selects one of the travel modes.

  The vehicle ECU 13 converts the required torque into a torque command value to be output by the engine 2 or the motor 3 based on the selected travel mode. For example, in the HEV mode, the required torque is distributed to the engine 2 side and the motor 3 side, and torque command values for the engine 2 and the motor 3 are calculated based on the gear position at that time. In the E / G mode, the required torque is converted into a torque command value for the engine 2 based on the gear position, and in the EV mode, the required torque is converted into a torque command value for the motor 3 based on the gear speed.

  The vehicle ECU 13 disconnects the clutch 4 in the EV mode and connects the clutch 4 in the E / G mode and HEV mode to execute the selected travel mode, and then sends a torque command value to the engine ECU 22 and the power conversion ECU 23. Is output as appropriate. While the vehicle 1 is traveling, the vehicle ECU 13 calculates a target gear position from a shift map (not shown) based on the accelerator operation amount θacc, the vehicle speed V, and the like, and the actuator 4 connects and disconnects the clutch 4 to achieve this target gear position. Executes operation and gear change operation.

  On the other hand, the engine ECU 22 executes injection amount control and injection timing control so as to achieve the travel mode and torque command value input from the vehicle ECU 13. For example, in the E / G mode and the HEV mode, the driving force is generated in the engine 2 with respect to the positive torque command value, and the engine brake is generated with respect to the negative torque command value. In the EV mode, the engine 2 is brought into a stopped holding state or an idle operation state by stopping fuel injection.

  Further, the power conversion ECU 23 controls the motor 3 via the power conversion device 10 so as to achieve the travel mode and the torque command value input from the vehicle ECU 13. For example, in the EV mode or HEV mode, the motor 3 is controlled by powering the positive torque command value to generate a positive driving force, and the motor 3 is regeneratively controlled to the negative torque command value. Generate negative driving force. In the E / G mode, the driving force of the motor 3 is controlled to zero. Therefore, in the present embodiment, the power conversion ECU 23 functions as a regeneration control unit that performs regeneration control on the motor 3 of the vehicle 1 and charges the battery 11 of the vehicle 1.

  The battery ECU 24 detects the temperature of the battery 11, the voltage of the battery 11, the current flowing between the power converter 10 and the battery 11, etc., and sequentially calculates the SOC of the battery 11 from these detection results and outputs it to the vehicle ECU 13. To do.

  On the other hand, the vehicle ECU 13 executes auto-cruise control. When the driver operates an auto cruise control execution switch (not shown) to set the target vehicle speed Vtgt, the vehicle ECU 13 sets the upper limit speed VHi and the lower limit speed VLo above and below the target vehicle speed Vtgt, and the vehicle 1 is traveling. Appropriately controls the driving force of the engine 2 and the motor 3 to keep the vehicle speed V between the upper limit speed VHi and the lower limit speed VLo. For example, the vehicle ECU 13 sets a negative required torque to maintain the vehicle speed V during traveling on a downhill road by auto-cruise control, and uses the potential energy of the vehicle 1 as electric energy and motion while achieving the required torque. In order to recover as energy, regeneration control and vehicle speed increase control of the motor 3 are executed. Then, the vehicle ECU 13 sets the required torque on the positive side to maintain the vehicle speed V during traveling on the uphill road by the automatic cruise control, and selects the traveling mode in view of the state of the battery 11 to control the vehicle speed increase. Execute.

  Further, the vehicle ECU 13 is configured to improve fuel efficiency when the vehicle is traveling during auto-cruise control and performs deceleration control regardless of the road inclination within the range of the upper limit speed VHi and the lower limit speed VLo. , An equal deceleration control estimation unit 41, an equal time calculation unit 42, and an unequal deceleration control determination unit 43. The data estimated by the equal deceleration control estimation unit 41 is supplied to and used by the equal time calculation unit 42, and the data calculated by the equal time calculation unit 42 is supplied to the unequal deceleration control determination unit 43. Thus, a data flow is formed as used. Note that these three components (equal deceleration control estimation unit 41, equal time calculation unit 42, unequal deceleration control determination unit 43) may be provided in the vehicle ECU 13 as a device in which each program is installed. Alternatively, it may exist in the vehicle ECU 13 as one program that processes the flow of data through these three configurations.

More specifically, the equal deceleration control estimation unit 41 receives road information related to a predetermined route ahead of the vehicle 1 from the navigation device 31 or the communication device 32. Based on the received road information, the uniform deceleration control estimation unit 41 determines the deceleration or driving force required when the vehicle 1 decelerates from the first vehicle speed to the second vehicle speed at a constant deceleration on a predetermined route. Estimate a constant deceleration fluctuation chart. Here, in the deceleration fluctuation chart, the horizontal axis is elapsed time (sec) and the vertical axis is deceleration (m / s ² ) or driving force (kW), and the amount of change in deceleration or driving force with respect to elapsed time is shown. It is a graph to show. Accordingly, there is an equal deceleration fluctuation chart corresponding to road information (for example, gradient, distance). The first vehicle speed and the second vehicle speed are arbitrary speeds set within a range between an upper limit speed VHi and a lower limit speed VLo related to auto-cruise control. Further, the deceleration is a value of deceleration expressed as negative (minus) when acceleration is positive (plus), and means negative acceleration. Further, the driving force is a force generated in a direction in which a positive (plus) driving force moves the vehicle 1 forward, and a force generated in a direction in which the negative (minus) driving force moves the vehicle 1 backward. Note that the force generated in the direction in which the vehicle 1 is moved backward is a braking force.

  The equal time calculation unit 42 calculates an integrated value of the deceleration using a constant deceleration fluctuation chart of the estimated deceleration. In other words, the equal time calculation unit 42 calculates the area (total deceleration) surrounded by the horizontal axis (time axis) and the deceleration constant deceleration variation chart in the deceleration uniform deceleration variation chart. . Further, the equal time calculation unit 42 corrects the equal deceleration variation chart of the estimated driving force so that the driving force at the first vehicle speed becomes zero (for example, the driving force at the first vehicle speed). Is a positive value, a chart in which the driving force equal deceleration fluctuation chart is shifted to the minus side by the driving force value at the first vehicle speed on the vertical axis, and the driving force at the first vehicle speed is a negative value. Alternatively, an integral value of a chart in which the driving force equal deceleration fluctuation chart is shifted to the plus side by the driving force value at the first vehicle speed on the vertical axis may be calculated. In other words, the equal time calculation unit 42 calculates the area (total driving force) surrounded by the horizontal axis (time axis) and the driving force equal deceleration correction chart in the driving force equal deceleration variation chart. . Further, the equally divided time calculating unit 42 divides each of the calculated two types of integral values into equal parts (that is, the elapsed time from the start of deceleration until the deceleration or the sum of the driving forces becomes ½). Is determined as the first equal time. Here, the first equally divided time varies depending on the gradient of the predetermined route, the first vehicle speed and the second vehicle speed, and the deceleration period.

The unequal deceleration control determination unit 43 receives road information related to a predetermined route ahead of the vehicle 1 from the navigation device 31 or the communication device 32. Then, similarly to the equal deceleration control estimation unit 41, the unequal deceleration control determination unit 43 performs the unequal deceleration from the first vehicle speed to the second vehicle speed on the predetermined route based on the received road information. An unequal deceleration fluctuation chart of deceleration and driving force required for deceleration is determined. Here, in the unequal deceleration fluctuation chart, the horizontal axis represents elapsed time (sec) and the vertical axis represents deceleration (m / s ² ) or driving force (kW), similar to the above-described equal deceleration fluctuation chart. It is a graph which shows the deceleration or the variation | change_quantity of a driving force with respect to elapsed time. The first vehicle speed and the second vehicle speed are arbitrary speeds set within the range of the upper limit speed VHi and the lower limit speed VLo related to auto-cruise control, and the deceleration means a negative acceleration. The driving force includes a force for moving the vehicle forward and a force for moving the vehicle backward.

  In the present embodiment, the unequal deceleration control determining unit 43 determines the unequal deceleration fluctuation chart in comparison with the deceleration or driving force equal deceleration fluctuation chart. Specifically, the equal time calculation unit 42 calculates the second equal time, which is the time from when the deceleration control start time for unequal deceleration is equal to the integral value of the deceleration during unequal deceleration. It is determined by the unequal deceleration control determining unit 43 so as to be later than the first equally divided time according to the deceleration equal deceleration fluctuation chart. Alternatively, in the unequal deceleration correction chart in which the driving force at the first vehicle speed is corrected to zero, this is the time from when the deceleration control start time of unequal deceleration is equally divided into the integral value of the driving force at unequal deceleration. The unequal deceleration control determining unit 43 determines the second equally divided time so as to be later than the first equally divided time according to the equal deceleration correction chart of the driving force calculated by the equally divided time calculating unit 42. . In other words, the unequal deceleration control determination unit 43 performs the second etc. so that the center of gravity position of the drive energy at the time of unequal deceleration is larger (that is, backward) than the position of the center of gravity of the drive energy at the time of equal deceleration. The minute time and unequal deceleration fluctuation chart will be determined. Note that the size of the first equally divided time and the second equally divided time will be described with reference to the drawings when explaining the control flow described later.

  From the above, at least one of the navigation device 31 and the communication device 32 functioning as a road information acquisition unit, an equal deceleration control estimation unit 41 that estimates an equal deceleration variation chart during equal deceleration, an equal deceleration variation chart, or an equal deceleration correction An equal time calculation unit 42 for calculating a first equal time from the chart, an unequal deceleration control determination unit 43 for determining an unequal deceleration fluctuation chart at the time of unequal deceleration in consideration of the first equal time, a deceleration The travel control device 50 according to the present embodiment is configured by the vehicle ECU 13 that functions as a control unit and the power conversion ECU 23 that functions as a regeneration control unit. With such a configuration of the traveling control device 50, when the vehicle 1 decelerates, the regeneration efficiency is improved regardless of the road gradient, which improves the fuel efficiency of the vehicle 1 and further reduces the environmental load on the vehicle 1. We can plan enough. Note that these effects will be described in detail together with a travel control flow of the vehicle 1 described later.

  Hereinafter, control of the vehicle 1 by the travel control device 50 will be described with reference to FIGS. 2 to 6. Here, FIG. 2 is a control flow showing the traveling control of the vehicle 1 by the traveling control device 50 according to the present embodiment. 3 is a diagram showing an equal deceleration variation chart and an unequal deceleration variation chart relating to acceleration (deceleration), and FIG. 4 is a diagram showing an equal deceleration variation chart and an unequal deceleration variation chart relating to driving force. Further, FIG. 5 is a simulation result showing a change in the vehicle speed in equal deceleration and unequal deceleration, and FIG. 6 is a simulation result showing a moving distance in equal deceleration and unequal deceleration.

  In the following control flow, it is assumed that the vehicle 1 travels on an expressway by auto-cruise control. In particular, a case will be described in which the upper limit speed VHi is set to the first vehicle speed, the lower limit speed VLo is set to the second vehicle speed, and the vehicle speed is decelerated from the first vehicle speed to the second vehicle speed using a route having a gradient of 0%. .

  First, road information relating to a predetermined route ahead of the vehicle 1 is acquired using at least one of the navigation device 31 and the communication device 32 (FIG. 2: step S1). The road information is used in calculation processing in steps S2 and S4 described later.

Next, the uniform deceleration control estimation unit 41 estimates a deceleration or a constant deceleration fluctuation chart of the driving force based on the received road information (FIG. 2: step S2). Specifically, on a predetermined route on which the vehicle 1 will travel, a deceleration or a constant deceleration fluctuation chart of the driving force required when the vehicle speed is decelerated from the first vehicle speed to the second vehicle speed by equal deceleration is estimated. To do. As an estimation result in the present embodiment, a constant deceleration fluctuation chart of deceleration is shown by a solid line in FIG. 3, and a constant deceleration fluctuation chart of driving force is shown by a solid line in FIG. Here, the horizontal axis in FIGS. 3 and 4 is time (second: sec), the vertical axis in FIG. 3 indicates acceleration (m / s ² ), and the vertical axis in FIG. 4 indicates driving force (kW). . In FIG. 3, the vertical axis represents acceleration (m / s ² ), but the deceleration (m / s ² ) is indicated by inverting the sign on the vertical axis. That is, in FIG. 3, the deceleration increases as the acceleration, which is the value on the vertical axis, decreases.

  As shown in FIG. 3, the deceleration period is from 4 seconds to 25 seconds, the period from 5 seconds to 24 seconds is controlled by the constant deceleration Acc1, and the period from 4 seconds to 5 seconds is zero deceleration. Is a preparation period for increasing the deceleration from the constant deceleration to the constant deceleration, and a period from 24 seconds to 25 seconds is a post-processing period for decreasing the deceleration from the uniform deceleration to zero deceleration. Therefore, the uniform deceleration fluctuation chart in the present embodiment includes the unequal deceleration period strictly. However, when the predetermined deceleration is reached, the deceleration is maintained over most of the deceleration period. Become.

On the other hand, the driving force, as shown in FIG. 4, during the period from 4 seconds deceleration increases to 5 seconds, the driving force is reduced from F _Drive 1 (plus) to F _Drive 2 (negative). That is, a force that moves the vehicle 1 forward is generated from 0 seconds to immediately after the start of deceleration, but a brake force that moves the vehicle 1 backward is generated immediately after the start of deceleration. Then, during the period from 5 seconds being controlled at a constant deceleration Acc1 to 24 seconds, the driving force is increased from F _Drive 2 (minus) to F _Drive 3 (minus). That is, the braking force gradually decreases during the period from 5 seconds to 24 seconds. Then, during the period from 24 seconds deceleration is reduced to 25 seconds, the driving force is increased F _Drive 3 from (minus) to F _Drive 4 (plus).

Next, the equal time calculation unit 42 calculates the integrated value of the deceleration during the deceleration period using the deceleration equal deceleration fluctuation chart shown in FIG. In the present embodiment, the equally divided time calculation unit 42 integrates the deceleration period from 4 seconds to 25 seconds with respect to the deceleration equal deceleration variation chart shown in FIG. By calculating the area surrounded by the deceleration fluctuation chart, the integral value of the deceleration is calculated. The equal time calculation unit 42 calculates an integral value related to the driving force during the deceleration period using the driving force deceleration fluctuation chart shown in FIG. 4. In the present embodiment, the equally divided time calculation unit 42 performs integration for the deceleration period from 4 seconds to 25 seconds, but the straight line whose driving force is F _Drive 1 (plus) (indicated by the broken line A in FIG. 4). The integral value related to the driving force is calculated by calculating the area surrounded by the constant deceleration fluctuation chart of the driving force. In other words, the equal time calculation unit 42 equalizes the drive force so that the value in 4 seconds of the drive force equal deceleration fluctuation chart (that is, F _Drive 1 (plus) at the first speed) becomes zero. The fluctuation chart is shifted to the minus side by F _Drive 1, and the integration for the deceleration period from 4 seconds to 25 seconds is performed for the constant deceleration correction chart that is the constant deceleration fluctuation chart in the shifted state. As a result, the area surrounded by the horizontal axis (that is, corresponding to the broken line A in FIG. 4) and the constant deceleration correction chart in the constant deceleration correction chart is calculated, and the integral value of the driving force in the constant deceleration correction chart is calculated. Will be. Then, the equal time calculation unit 42 calculates a first equal time that is a time until the deceleration or the integrated value of the driving force calculated from the start of deceleration is equally divided (FIG. 2: step S3). In the present embodiment, the integrated value is equally divided by the period from the start of deceleration to 12 seconds and the period from the lapse of 12 seconds to the end of deceleration, so the first equally divided time is 12 seconds.

  Next, the unequal deceleration control determination unit 43 determines an unequal deceleration variation chart of deceleration or driving force based on the received road information and the uniform deceleration variation chart (FIG. 2: step S4). Specifically, the equal time calculation unit 42 calculates the second equal time, which is the time from when the deceleration control start time for unequal deceleration is equal to the integral value of the deceleration during unequal deceleration. The unequal deceleration variation chart for deceleration is determined by the unequal deceleration control determination unit 43 so as to be longer than 12 seconds, which is the first equally divided time related to the deceleration uniform deceleration variation chart. In the present embodiment, the unequal deceleration fluctuation chart is determined so that the second equally divided time associated with the deceleration unequal deceleration fluctuation chart is longer than 12 seconds. In particular, as shown in FIG. 3, in the unequal deceleration fluctuation chart of deceleration (unequal deceleration 1 shown by a broken line) in this embodiment, the deceleration is the maximum value Acc2 in about 14 seconds (10 seconds after the start of deceleration). As shown, the curve is convex toward the negative side of the graph.

On the other hand, the unequal deceleration fluctuation chart of the driving force was corrected so that the value in 4 seconds (that is, F _Drive 1 (plus) at the first speed) of the unequal deceleration fluctuation chart of the driving force becomes zero. In the unequal deceleration correction chart in the state, it is assumed that integration is performed for the deceleration period from 4 seconds to 25 seconds. Then, the second equally divided time, which is the time until the area surrounded by the horizontal axis and the unequal deceleration correction chart in the unequal deceleration fluctuation chart is equally divided from the deceleration control start time of unequal deceleration, is calculated as an equal time. The unequal deceleration variation chart for the driving force is determined by the unequal deceleration control determining unit 43 so as to be later than the first equally divided time associated with the equal deceleration correction chart for the driving force calculated by the unit 42. In particular, as shown in FIG. 4, the driving force unequal deceleration fluctuation chart (unequal deceleration 1 shown by a broken line) in the present embodiment has a driving force having a minimum value F in about 12 seconds (8 seconds after the start of deceleration). _The curve is convex toward the minus side of the graph so that _Drive 5 (minus) is obtained.

  In FIG. 3, another example of the unequal deceleration fluctuation chart relating to the deceleration determined so that the second equal time related to the deceleration is earlier than the first equal time is also used as a comparative example. It is shown (unequal deceleration 2 shown with the dashed-dotted line of FIG. 3). Similarly, in FIG. 4, another example of the unequal deceleration fluctuation chart relating to the drive amount that is determined so that the second equally divided time related to the driving force is earlier than the first equally divided time is also a comparative example. (Unequal deceleration 2 shown by the one-dot chain line in FIG. 4).

  Next, when the vehicle 1 reaches a predetermined route, the vehicle ECU 13 controls the braking device 33 based on any of the determined unequal deceleration fluctuation charts (FIG. 2: step S5). That is, the vehicle ECU 13 changes the deceleration of the vehicle 1 along the unequal deceleration fluctuation chart of deceleration shown in FIG. 3, or the motive power of the vehicle 1 shows the unequal deceleration fluctuation chart of driving force shown in FIG. Will change along.

  As a result of such deceleration control, a simulation result is obtained in which the vehicle speed changes as shown in FIG. Specifically, the vehicle speed of unequal deceleration based on one of the determined unequal deceleration fluctuation charts (unequal deceleration 1 shown by a broken line) is compared with the vehicle speed of uniform deceleration (shown by a solid line) in about 2 seconds from the start of deceleration. Although it decreases gradually, the deceleration amount increases compared to the constant deceleration vehicle speed after about 2 seconds from the start of deceleration, and again compared with the constant deceleration vehicle speed after about 16 seconds from the start of deceleration. The vehicle gradually decelerates and finally becomes the same as the vehicle speed in the case of equal deceleration, that is, the second vehicle speed. On the other hand, in the above-mentioned other unequal deceleration fluctuation chart (unequal deceleration 2 indicated by a one-dot chain line), the deceleration amount is large from the start of deceleration compared with the vehicle speed of equal deceleration, and after about 16 seconds from the start of deceleration, etc. Compared to the vehicle speed of deceleration, the vehicle speed decreases gently, and the vehicle speed finally becomes the same as the vehicle speed in the case of equal deceleration.

  Furthermore, by such deceleration control, the simulation result of the travel distance (km) as shown in FIG. 6 and the improvement rate of the regenerative energy per unit distance for the constant deceleration control as shown in Table 1 below. Simulation results were obtained. Here, when the numerical value of Table 1 is larger than 1, it shows improvement, and when it is smaller than 1, it shows deterioration.

  Here, the other unequal deceleration is a case where the unequal deceleration fluctuation chart is determined so that the second equal time is earlier than the first equal time as described above.

  As shown in Table 1, the deceleration control by unequal deceleration according to the present embodiment has a large improvement rate of regenerative energy per unit distance compared to the deceleration control of equal deceleration and other deceleration control of unequal deceleration. I understand that. That is, the deceleration control by unequal deceleration according to the present embodiment has the highest regeneration efficiency among the above three deceleration controls.

  In addition, as shown in FIG. 6, in the unequal deceleration according to the present embodiment, the moving distance is smaller than that in the case of equal deceleration (equal deceleration indicated by a solid line) at the time point when 30 seconds have elapsed. This is larger than the case of unequal deceleration (unequal deceleration 2 indicated by a one-dot chain line). That is, by performing the deceleration control using the unequal deceleration fluctuation chart according to the present embodiment, the arrival time to a predetermined movement distance (destination) is shortened compared to the deceleration control using the other unequal deceleration fluctuation chart. Will be.

  From the above, in the deceleration control according to the present embodiment, in addition to the point that the regenerative efficiency is the most excellent, the travel time of the vehicle 1 can be made relatively long and the arrival time can be shortened. Compared with the deceleration control with equal deceleration and the deceleration control with other unequal deceleration, the fuel consumption can be further reduced. Therefore, the deceleration control according to the present embodiment is very effective when, for example, a lot of electricity is used at the destination of the vehicle 1 or when there is a high demand for using additional functions such as a refrigerator or an air conditioner. Control can be realized.

  Although the deceleration control described above assumes a case where the gradient of the predetermined path is 0%, regeneration due to deceleration occurs regardless of the magnitude of the gradient. Therefore, although the numerical values in Table 1 are different, the gradient is 0. Similar results are obtained when the ratio is greater than% and less than 0%. That is, even on the uphill road and the downhill road, the deceleration control according to the present embodiment realizes further reduction in fuel consumption as compared with the deceleration control of equal deceleration and the deceleration control of other unequal deceleration. Become.

  In the above-described embodiment, the case of the deceleration control during the auto cruise control has been described. However, the travel control related to the present invention is not limited to the case of the auto cruise, and is also used as an automatic deceleration control during general travel. can do. Furthermore, although the above embodiment has been described on the premise of a hybrid vehicle, the vehicle control device according to the present invention can also be applied to an electric vehicle using only a motor as a drive source.

1 Hybrid vehicle (vehicle)
2 Engine 3 Motor (electric motor)
4 Clutch 5 Automatic Transmission 6 Propeller Shaft 7 Differential Device 8 Drive Shaft 9 Drive Wheel 10 Power Conversion Device 11 Battery 13 Vehicle ECU (Deceleration Control Unit)
DESCRIPTION OF SYMBOLS 14 Accelerator pedal 15 Accelerator sensor 16 Brake pedal 17 Brake switch 18 Vehicle speed sensor 19 Engine rotational speed sensor 20 Motor rotational speed sensor 22 Engine ECU
23 Power conversion ECU (regenerative control unit)
24 battery ECU
31 Navigation device (road information acquisition unit)
32 Communication device (road information acquisition unit)
DESCRIPTION OF SYMBOLS 33 Braking device 41 Equal deceleration control estimation part 42 Equal time calculation part 43 Unequal deceleration control determination part 50 Control apparatus

Claims (1)

A road information acquisition unit that acquires road information related to a predetermined route ahead of the vehicle;
Based on the road information, a deceleration or driving force equal deceleration variation chart required when the vehicle decelerates from the first vehicle speed to the second vehicle speed at a constant deceleration in a predetermined time on the predetermined route, etc. A deceleration control estimation unit;
The integrated value of the deceleration in the constant deceleration variation chart of the deceleration or the integrated value of the driving force in the constant deceleration correction chart in which the driving force at the first vehicle speed is corrected to zero in the constant deceleration variation chart of the driving force An equal time calculation unit that calculates and calculates a first equal time that is a time from the deceleration control start time until the integral value is equally divided;
Based on the road information, deceleration or unequal deceleration fluctuation of driving force required when the vehicle decelerates at the predetermined time from the first vehicle speed to the second vehicle speed at the predetermined time on the predetermined route. The chart is the integral value of the deceleration at the time of unequal deceleration in the deceleration unequal deceleration fluctuation chart from the deceleration control start time or the unequal deceleration fluctuation chart of the driving force from the deceleration control start time at the first vehicle speed. In the unequal deceleration correction chart in which the driving force is corrected to zero, the second equal time, which is the time until the integral value of the driving force at the time of unequal deceleration, is equally divided is later than the first equal time. An unequal deceleration control deciding unit that decides
A deceleration control unit for controlling the deceleration of the vehicle by controlling the braking device of the vehicle based on the unequal deceleration fluctuation chart;
A vehicle travel control device comprising: a regeneration control unit that regeneratively controls the motor of the vehicle based on the unequal deceleration fluctuation chart and charges the battery of the vehicle.

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