JP2015101145A - Travel control unit of hybrid electric vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a travel control unit of a hybrid electric vehicle, capable of achieving comprehensive reduction in fuel consumption by efficiently using electric power generated by rotating a motor by an engine in a hybrid electric vehicle.SOLUTION: A hybrid electric vehicle 1 including an engine and a motor as travel driving sources, implements an engine-power-generation travel mode for generating a requested torque DT by the engine and generating electric power by rotating the motor in a period ΔT1 that is a first half of a low load interval, and implements a motor travel mode for generating the requested torque DT by the motor using the electric power generated in the engine-power-generation travel mode in a period ΔT-ΔT1 that is a second half of the low load interval.

Description

  The present invention relates to a travel control device for a hybrid vehicle including an engine and a motor as travel drive sources.

  In recent hybrid vehicles, a road environment information (hereinafter referred to as route information) on a travel route ahead of the vehicle is acquired using a navigation system or the like, and the fuel consumption rate of the engine is minimized by using the route information. As described above, development of technology for controlling an engine and a motor is underway.

  For example, in Patent Document 1, the predicted value of the engine operating point is calculated from the vehicle speed predicted value and the braking / driving force predicted value of the vehicle on the travel route using the route information, and preferentially in a place where the fuel consumption rate is bad. Electricity is generated by rotating a motor with an engine. Thereby, the operating point is changed so that the fuel consumption rate of the engine becomes a better value, the fuel consumption rate at that point is improved, and the fuel consumption amount in the section is minimized.

JP 2000-324609 A

  In the technique described in Patent Document 1, the engine load is increased to an area where the fuel consumption rate is good by rotating the motor with the engine in a low load section where the fuel consumption rate of the engine is low such as a gentle downhill road. The fuel consumption rate of the engine is increased by the amount of power generation.

  Since a motor, an inverter, a battery, etc. always cause a loss due to charging / discharging, it is not possible to use all the electric power (energy) obtained by power generation by the engine as power for the motor. In other words, if a motor is simply used as an engine assist, it is not possible to recover all of the energy for the fuel used for power generation by the engine. is there.

  The present invention was made to solve such problems, and the object of the present invention is to efficiently use electric power obtained by generating electric power by rotating a motor with an engine in a hybrid vehicle. An object of the present invention is to provide a travel control device for a hybrid vehicle that can reduce fuel consumption comprehensively.

  In order to achieve the above-described object, in the first invention, an engine and a motor as a driving source for driving a vehicle, a route information acquisition unit that acquires route information ahead of the vehicle, and the route information acquisition unit Based on the acquired route information, a driving state of the vehicle at each point is predicted, and a low load section detecting unit that detects a low load section where the required torque is equal to or less than a predetermined low load determination threshold, and within the low load section An engine power generation travel mode in which the engine generates the required torque and generates electric power by rotating the motor, and a motor that generates the required torque by the motor using electric power generated in the engine power generation travel mode. A travel mode setting unit configured to set each execution range of the travel mode, and the travel mode setting when the vehicle travels in the low load section. Comprising a low-load running control unit for controlling the engine and the motor according to the execution range of the engine generator running mode and motor drive mode set by the section, the.

  In a second invention, in the first invention, the travel mode setting unit uses the engine power so that the electric power generated in the engine power generation travel mode is used up at the end point of the low load section in the motor travel mode. An execution range of the power generation travel mode and the motor travel mode is set.

  According to a third invention, in the first or second invention, the battery on the route ahead of the vehicle based on the battery that supplies power to the motor and the route information obtained by the route information obtaining unit. A charge amount prediction unit for predicting a charge amount of the battery, wherein the low load travel control unit has a predetermined charge amount of the battery at the start point of the low load section predicted by the charge amount prediction unit. When the amount is equal to or less than the predetermined amount, the engine and the motor are controlled according to the execution range of the engine power generation travel mode and the motor travel mode set by the travel mode setting unit.

  According to a fourth aspect, in the third aspect, the travel mode setting unit sets a target charge amount that uses up the electric power generated in the engine power generation travel mode at the end point of the low load section in the motor travel mode. The low load travel control unit switches to the motor travel mode when the charge amount of the battery reaches the target charge amount by the electric power generated in the engine power generation travel mode in the low load section.

  In a fifth invention, in any one of the first to fourth inventions, the low load travel control unit is set by the travel mode setting unit when the vehicle travels in the low load section. The engine and the motor are controlled so as to maintain the target vehicle speed set by the driver in accordance with the execution range of the engine power generation travel mode and the motor travel mode.

  According to the present invention using the above means, in a hybrid vehicle, it is possible to efficiently use electric power obtained by generating electric power by rotating a motor by an engine, and to reduce fuel consumption comprehensively.

1 is a schematic configuration diagram of a hybrid vehicle including a travel control device according to an embodiment of the present invention. It is a flowchart which shows the driving mode setting routine in low load driving control. It is a flowchart which shows the driving mode execution routine in low load driving control. It is explanatory drawing which shows transition of the various driving | running states when low load driving control is performed.

FIG. 1 is an overall configuration diagram showing a hybrid vehicle equipped with a travel control device of the present embodiment.
The hybrid vehicle 1 is configured as a so-called parallel hybrid truck, and may be referred to as a vehicle in the following description.

  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 that can also operate as a generator such as a permanent magnet synchronous motor. 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 is based on a general manual transmission and automates the engagement / disengagement operation of the clutch 4 and the switching operation of the shift speed. In this embodiment, the automatic transmission 5 has a forward speed 6 speed, reverse speed 1 speed. doing. Of course, the configuration of the transmission 5 is not limited to this, and can be arbitrarily changed. For example, the transmission 5 may be embodied as a manual transmission, or a so-called dual clutch automatic transmission having two power transmission systems. It may be embodied as a machine.

  A battery 11 is connected to the motor 3 via an inverter 10. The DC power stored in the battery 11 is converted into AC power by the inverter 10 and supplied to the motor 3, and the driving force generated by the motor 3 is transmitted to the drive wheels 9 after being shifted by the automatic transmission 5. (This is called power running). 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. The negative driving force generated by the motor 3 is transmitted to the driving wheel 9 side as a braking force, and the AC power generated by the motor 3 is converted into DC power by the inverter 10 and charged to the battery 11 (this is This is called regenerative operation). Furthermore, the motor 3 can be rotated by the driving force generated by the engine 2 to generate electric power, and the battery 11 can be charged (this is called engine power generation).

  The driving force generated by the motor 3 is transmitted to the driving wheel 9 regardless of the state of connection / disconnection of the clutch 4, and the driving force generated by the engine 2 is driven only when the clutch 4 is connected. 9 side. 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 side, so that 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 for detecting the operation amount of the accelerator pedal 14, a brake switch 17 for detecting the depression operation of the brake pedal 16, a vehicle speed sensor 18 for detecting the speed of the vehicle 1, and the rotational speed of the engine 2. Various sensors and switches such as an engine rotation speed sensor 19 for detecting and a motor rotation speed sensor 20 for detecting the rotation speed of the motor 3 are connected.

  The vehicle ECU 13 is connected with an actuator (not shown) for connecting / disconnecting the clutch 4 and an actuator for shifting the automatic transmission 5, and an engine ECU 22 for engine control and an inverter ECU 23 for inverter control. And a battery ECU 24 for managing the battery 11 are connected.

  The vehicle ECU 13 calculates a required torque necessary for the vehicle 1 to travel based on the accelerator operation amount by the driver, and the vehicle 1 is based on the required torque, the SOC (State Of Charge) of the battery 11, and the like. Select the driving mode. In the present embodiment, as the travel mode, an engine travel mode that travels using only the driving force of the engine 2, a motor travel mode that travels using only the driving force of the motor 3, and the driving forces of the engine 2 and the motor 3 are used. A hybrid traveling mode in which the vehicle 2 travels and an engine power generation traveling mode in which power is generated by rotating the motor 3 using the driving force of the engine 2 while traveling using the driving force of the engine 2 are set. The vehicle ECU 13 selects the travel mode.

  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 hybrid travel 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 engine travel mode, the required torque is converted into a torque command value for the engine 2 based on the gear position, and in the motor travel mode, the required torque is converted into a torque command value for the motor 3 based on the gear speed. Further, in the engine power generation travel mode, a value obtained by combining the required torque and the torque required for power generation by the motor 3 is calculated as a torque command value for the engine 2.

  Then, in order to execute the selected travel mode, the vehicle ECU 13 disconnects the clutch 4 in the motor travel mode and connects the clutch 4 in the engine travel mode, the hybrid travel mode, and the engine power travel mode, and then the engine ECU 22 and the inverter A torque command value is appropriately output to the ECU 23. 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, the vehicle speed, and the like, and the actuator 4 connects and disconnects the clutch 4 to achieve this target gear position. A gear change operation is executed.

  On the other hand, the engine ECU 22 executes injection amount control and injection timing control so as to achieve a torque command value based on the travel mode selected by the vehicle ECU 13. For example, in the engine travel mode, the hybrid travel mode, and the engine power generation travel 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 case of the motor travel mode, the engine 2 is stopped and held by stopping the fuel injection or is set in an idle operation state.

  Further, the inverter ECU 23 drives and controls the motor 3 via the inverter 10 so as to achieve a torque command value based on the travel mode selected in the vehicle ECU 13. For example, in the motor travel mode and the hybrid travel mode, the motor 3 is power-running with respect to the positive torque command value to generate a positive drive force, and the motor 3 is regeneratively controlled with respect to the negative torque command value. Thus, a negative driving force is generated. In the case of the engine running mode, the driving force of the motor 3 is controlled to zero. Further, in the case of the engine power generation travel mode, power is generated by receiving the driving force of the engine 2.

  Further, the battery ECU 24 detects the temperature of the battery 11, the voltage of the battery 11, the current flowing between the inverter 10 and the battery 11, and calculates the SOC (charge amount) of the battery 11 from these detection results. This SOC is output to the vehicle ECU 13 together with the detection result.

  On the other hand, the vehicle ECU 13 can execute auto-cruise control for controlling the engine 2 and the motor 3 so as to maintain the target vehicle speed VSt set by the driver. When the driver operates an auto cruise control execution switch (not shown) to set the target vehicle speed VSt, the vehicle ECU 13 controls the torque of the engine 2 and the motor 3 so that the vehicle speed VS becomes the target vehicle speed VSt. Decelerate.

  In the auto-cruise control in the present embodiment, the driving mode is selected after the driving state of the vehicle 1 at each point is predicted based on road environment information (route information) on the driving route ahead of the vehicle. Therefore, a navigation device 31 is connected to the vehicle ECU 13 as shown in FIG. 1 in order to detect route information ahead of the vehicle.

  The navigation device 31 is based on the map data stored in its own storage area and the GPS information or VICS (registered trademark) information received via the antenna, while the vehicle position on the map and Identify the road surface gradient and curve in front of the vehicle.

  In the auto cruise control, the vehicle ECU 13 acquires, for example, road surface gradient information from these navigation devices 31 and classifies a route ahead of the vehicle based on the road surface gradient information. For example, in the downhill road section, the motor travel mode is set to perform the regenerative operation. In the uphill road or flat road section, the motor travel mode is set if the SOC predicted in the section is relatively large, and the engine travel mode is set if the SOC is relatively small.

  In particular, in the present embodiment, when there is a low load section such as a gentle downhill road where the fuel efficiency of the engine 2 deteriorates on the route ahead of the vehicle, and the SOC in the low load section is 0 or a very small amount. The low load traveling control combining the engine power generation traveling mode and the motor traveling mode is executed.

  Specifically, as shown in FIG. 1, the vehicle ECU 13 includes a low load travel control unit 40 for executing low load travel control. The low load travel control unit 40 includes a route information acquisition unit 41, a low load travel control unit 40, and a low load travel control unit 40. A load section detection unit 42, an SOC prediction unit 43, and a travel mode setting unit 44 are included.

  The low-load travel control unit 40 acquires the route information ahead of the host vehicle detected by the navigation device 31 at the route information acquisition unit 41. Then, the route information acquisition unit 41 calculates the required torque DT necessary to maintain the target vehicle speed VSt based on the road gradient at each point ahead of the host vehicle, the weight of the host vehicle, and the like.

  The low load section detection unit 42 calculates a required torque or the like required to maintain the target vehicle speed VSt at each point from the weight information of the own vehicle or the road surface gradient information included in the acquired route information. A low load section in which the torque is equal to or less than a predetermined low load determination threshold value DTa is detected. The low load section detector 42 also determines whether or not the low load travel time ΔT required when the detected low load section travels at the target vehicle speed VSt is longer than a predetermined time Ta. The predetermined time Ta is a time arbitrarily set so that the clutch 4 is not frequently engaged / disconnected in consideration of the engagement / disengagement time of the clutch 4 associated with switching from the engine power generation travel mode to the motor travel mode.

  The SOC prediction unit 43 acquires the SOC information of the battery 11 from the battery ECU 24, and predicts the SOC at each point from the route information, the predicted operating state, and the like. The SOC prediction unit 43 also determines whether or not the SOC at the low load section start point is equal to or less than a predetermined value Sa. The predetermined value Sa is set to an allowable lower limit value of SOC that requires engine power generation.

  The travel mode setting unit 44 sets a ratio between a range in which the engine power generation travel mode is executed in the low load section and a range in which the motor travel mode is subsequently executed based on the required torque DT. This is because, of the traveling time ΔT required when traveling in the low load section at the target vehicle speed VSt, the period of traveling in the engine power generation traveling mode is ΔT1, and the remaining amount of charge charged to the battery 11 during the ΔT1 is the remaining amount. The ratio ΔT: T−ΔT1 between the execution range of the engine power generation travel mode and the execution range of the motor travel mode is set so as to be used up by the motor travel mode during the period (T−ΔT1).

  Specifically, ΔT1 is calculated by the following equation (1) obtained from the following equation (1) in which the charge amount charged in the battery 11 in the engine power generation travel mode is equal to the charge amount consumed from the battery 11 in the motor travel mode. calculate.

ΔT1 × CPave = (ΔT−ΔT1) × MPave (1)
ΔT1 = ΔT × MPave / (CPave + MPave) (2)
Here, when traveling in the engine power generation traveling mode in the low load section, the average charge amount CPave per unit time charged in the battery 11 and the average motor work MPave per unit time necessary for traveling in the motor traveling mode are: The fuel consumption can be calculated from the characteristic map of the engine 2 and the motor 3 so as to minimize the fuel consumption.

  For example, the average charge amount CPave is equal to or greater than the average required torque DTave from the characteristic map of the engine 2, the fuel efficiency is optimal, and the motor 2 is operated with the best motor efficiency from the characteristic map of the motor 3 when the motor 3 generates power. A point is calculated and calculated as being generated by a torque exceeding the average required torque. The average motor work MPave corresponds to a work required to output an average required torque DTave that can reduce fuel consumption by running the motor based on a characteristic map of the engine 2 and the motor 3.

Further, the travel mode setting unit 44 sets a target SOC St (amount accumulated from the target charge amount (= ΔT1 × CPave)) in the low load section from the travel period ΔT1 of the engine power generation travel mode and the average charge amount CPave. .
When the vehicle 1 travels in a low-load section, the low-load travel control unit 40 passes through the engine ECU 22 to execute the engine power generation travel mode and the motor travel mode at the ratio set in the travel mode setting unit 44. The engine 2 and the motor 3 are controlled via the inverter ECU 23, respectively.

  2 and 3, FIG. 2 is a flowchart showing a travel mode setting routine in low-load travel control, and FIG. 3 is a travel mode execution routine in low-load travel control. The flow of the low load traveling control in the present embodiment will be described along the flowchart. Note that the low-load running control is performed during execution of auto-cruise control.

First, as illustrated in FIG. 2, the low-load travel control unit 40 acquires route information in front of the host vehicle detected by the navigation device 31 in the route information acquisition unit 41 as step S1.
In step S2, the low load section detector 42 calculates the required torque DT at each point, and determines whether or not a low load section in which the required torque DT is equal to or lower than the low load determination threshold DTa is detected. When the determination result is false (No), that is, when there is no low load section ahead of the vehicle, the low load traveling control need not be performed, and the routine ends. On the other hand, when the determination result is true (Yes), the process proceeds to the next step S3.

  In step S3, the low load section detector 42 determines whether or not the low load travel time ΔT required when traveling in the low load section at the target vehicle speed VSt is longer than the predetermined time Ta. The routine is also terminated if the determination result is false (No). On the other hand, if the determination result is true (Yes), the process proceeds to the next step S4.

  In step S4, the SOC prediction unit 43 determines whether or not the SOC at the start point of the low load section is less than or equal to a predetermined value Sa. If the determination result is false (No), the routine ends. On the other hand, if the determination result is true (Yes), the process proceeds to the next step S5.

  In step S5, the travel mode setting unit 44 sets a ratio between a range in which the engine power generation travel mode is executed and a range in which the motor travel mode is executed in the low load section. Specifically, the period ΔT1 for traveling in the engine power generation traveling mode is set from the above-described equation (2), and the remaining period T−ΔT1 is set as the period for the motor traveling mode.

In the next step S6, the travel mode setting unit 44 sets the target SOC St (= ΔT1 × CPave) in the low load section from the travel period ΔT1 in the engine power generation travel mode and the average charge amount CPave.
Thus, after setting the ratio of the range of the engine power generation travel mode and the range of the motor travel mode in the low load section based on the travel mode setting routine, the low load travel control unit 40 executes the travel mode execution shown in FIG. Run the routine.

  Specifically, as illustrated in FIG. 3, the low load travel control unit 40 determines whether or not the vehicle 1 has reached the start point of the low load section in step S <b> 10. If the determination result is false (No), it is not yet time to execute the low-load running control, and thus the determination in step S10 is repeated. On the other hand, if the determination result is true (Yes), the process proceeds to the next step S11.

In step S <b> 11, the low load travel control unit 40 executes the engine power generation travel mode from the low load section start point.
In step S12, the low-load travel control unit 40 determines whether or not the SOC of the battery 11 is greater than the target SOC St. If the determination result is false (No), the determination in step S12 is repeated. On the other hand, if the determination result is true (Yes), the process proceeds to the next step S13.

In step S13, the low load traveling control unit 40 switches the traveling mode to the motor traveling mode.
In step S14, the low-load travel control unit 40 determines whether the vehicle 1 has reached the end point of the low-load section or whether the SOC has become equal to or less than a predetermined value Sa that is an allowable lower limit value. If the determination result is false (No), the determination in step S12 is repeated. On the other hand, if the determination result is true (Yes), the routine ends.

  Here, FIG. 4 is an explanatory diagram showing transitions of various operation states when the low load traveling control is executed. Specifically, as the various driving states, the altitude and gradient of the route ahead of the vehicle, the required torque, the engine torque, the motor torque, the SOC, and the fuel consumption are shown. In FIG. 4, various operation states are simply shown so that the transitions can be easily understood. Hereinafter, based on the same figure, the effect of the traveling control apparatus of the hybrid vehicle which concerns on this embodiment is demonstrated.

  First, the vehicle 1 acquires the route information ahead of the host vehicle, thereby recognizing the altitude and the road surface gradient of the route ahead of the host vehicle as shown in FIG. Then, the required torque DT necessary for traveling at the target vehicle speed VSt is calculated from the gradient of each point, and the points s1 to s3 where the required torque DT is within the low load determination threshold value DTa are detected as low load sections. Is done. In addition, the transition of the SOC is also predicted, and the low load traveling control is executed from the s1 point to the s3 point because the s1 point which is the starting point of the low load section is below the allowable lower limit value (predetermined value Sa) of the SOC. The

  Further, as shown in FIG. 4, the engine torque is increased to the required torque or more by setting the engine power generation travel mode in the first half of the low load section obtained from the above formula (2), and the engine becomes surplus. The engine torque is used for power generation by the motor 3, and the SOC is charged to the target SOC St. In the remaining period ΔT−ΔT1, the motor travel mode is set, and travel is performed only by the motor 3 so that the SOC charged up to the target SOC St is used up.

  In this way, in the low load section, the first half operates the engine 2 with fuel efficiency in the engine power generation travel mode, and the second half runs with the motor 3 with the engine 2 in the idling state, thereby reducing the fuel consumption in the low load section. Minimized.

  In FIG. 4, the engine torque and the fuel consumption when the entire low load section is traveled in the engine travel mode are indicated by broken lines. Compared with the fuel consumption of this embodiment shown by the solid line, in this embodiment, the increase in fuel consumption increases from the s1 point to the s2 point because the engine torque is increased by the amount of power generated by the motor 3. However, after shifting to the motor travel mode from the point s2, only the fuel for idling is consumed, and the increase in fuel consumption is suppressed. The fuel consumption can be reduced at the point s3 which is the end point of the low load section as compared with the case where the vehicle travels only in the engine travel mode.

  As described above, in the low load traveling control in the present embodiment, in the low load section, the engine 2 performs the fuel efficient operation in the first half and is in the idling state in the second half, and the electric power generated by the engine 2 in the first half is traveled by the motor. It can be used more efficiently and the fuel consumption can be reduced comprehensively.

  In addition, the execution range of the engine power generation travel mode and the motor travel mode is set so that the power generated in the engine power generation travel mode is used up in the motor travel mode. It will not leave behind. Thus, for example, even when there is a long downhill immediately after the end of the low load section, the SOC of the battery 11 can be charged from 0 to the upper limit by the regenerative operation of the motor 3, and the electric power generated in the engine power generation travel mode Can be used inefficiently. That is, by using up the SOC in the low load section, the fuel efficiency improvement effect can be surely obtained regardless of the route state after the end of the low load section.

  Also, by performing low-load traveling control only when the SOC is equal to or less than the predetermined value Sa, traveling in the motor traveling mode as efficiently as possible over a wide range even when the low-load section cannot be traveled in the motor traveling mode. It can be performed. On the other hand, when the SOC of the battery 11 is sufficient before the start of the low load section, it is possible to prevent the engine power generation travel mode from being performed wastefully.

Furthermore, since the switching of the traveling mode in the low load traveling control is performed when the SOC of the battery 11 reaches the target SOC St, the traveling mode switching control can be facilitated.
And since the low load traveling control in this embodiment is performed as a part of auto-cruise control, the fuel consumption in auto-cruise control can be reduced reliably.

Although the description about the embodiment of the travel control device for a hybrid vehicle according to the present invention is finished above, the embodiment is not limited to the above embodiment.
In the above embodiment, the low load traveling control is executed as part of the auto cruise control, but the low load traveling control is not necessarily limited to that executed during the auto cruise control. For example, if it is possible to obtain route information ahead of the vehicle, estimate the required torque and vehicle speed at each point from the driving history, etc., and calculate the low load section and the travel time ΔT of the low load section, it is only during auto cruise control. The low load traveling control according to the present invention can be applied.

  In addition to the above embodiment, when it is predicted that the SOC at the time of entering the low load section will not reach the allowable lower limit value (predetermined value Sa), the SOC is used up to the allowable lower limit value before entering the low load section. Or a point where the SOC is used up can be further predicted and the low-load running control can be started from that point.

2 Engine 3 Motor 4 Clutch 11 Battery 13 Vehicle ECU
22 Engine ECU
23 Inverter ECU
31 navigation device 40 low load travel control unit 41 route information acquisition unit 42 low load section detection unit 43 SOC prediction unit (charge amount prediction unit)
44 Driving mode setting section

Claims (5)

An engine and a motor as driving sources for driving the vehicle;
A route information acquisition unit for acquiring route information ahead of the vehicle;
A low load section detection unit that predicts the driving state of the vehicle at each point based on the route information acquired by the route information acquisition unit and detects a low load section in which the required torque is equal to or less than a predetermined low load determination threshold;
In the low load section, the engine generates the required torque and rotates the motor to generate electric power, and the motor uses the electric power generated in the engine power generation traveling mode. A travel mode setting unit that sets each execution range of the motor travel mode that generates the required torque;
A low-load travel control unit that controls the engine and the motor according to an execution range of the engine power generation travel mode and the motor travel mode set by the travel mode setting unit when the vehicle travels in the low-load section;
A travel control device for a hybrid vehicle comprising:   The travel mode setting unit sets an execution range of the engine power generation travel mode and the motor travel mode so that the electric power generated in the engine power generation travel mode is used up at an end point of the low load section by the motor travel mode. The travel control apparatus for a hybrid vehicle according to claim 1. A battery for supplying power to the motor;
A charge amount prediction unit that predicts the charge amount of the battery on the route ahead of the vehicle based on the route information acquired by the route information acquisition unit;
The low load travel control unit is set by the travel mode setting unit when the charge amount of the battery at the low load section start point predicted by the charge amount prediction unit is equal to or less than a predetermined amount. The travel control device for a hybrid vehicle according to claim 1 or 2, wherein the engine and the motor are controlled in accordance with an execution range of the engine power generation travel mode and the motor travel mode. The travel mode setting unit sets a target charge amount that uses up the electric power generated in the engine power generation travel mode at the low load section end point in the motor travel mode,
The low-load travel control unit switches to the motor travel mode when the charge amount of the battery reaches the target charge amount by the electric power generated in the engine power generation travel mode in the low-load section. A travel control device for a hybrid vehicle.   The low-load travel control unit is set by a driver according to an execution range of the engine power generation travel mode and the motor travel mode set by the travel mode setting unit when the vehicle travels in the low-load section. The travel control device for a hybrid vehicle according to any one of claims 1 to 4, wherein the engine and the motor are controlled so as to maintain the target vehicle speed.

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