JP2006223073A - Device and method for controlling hybrid vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To achieve high-accuracy travel control without disturbing the behavior of a vehicle even in steering operation, in a device for controlling a hybrid vehicle that drives either of front wheels and rear wheels by an engine, and drives the other by a motor generator. <P>SOLUTION: In the device, a steering angle of a steering wheel is detected. When the steering angle reaches a value not smaller than a preset value that affects the behavior of the vehicle, preset travel control is performed in the operation of the steering wheel different from normal travel control. In other words, since a control amount is corrected in consideration of the steering angle of the steering wheel at the curve traveling of the vehicle, and a traveling mode is selected, the disturbance of the behavior of the vehicle can be prevented or suppressed. Furthermore, since the travel control is executed without discontinuance, the high-accuracy travel control is achieved. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a hybrid vehicle control device and a hybrid vehicle control method, and more particularly to a hybrid vehicle control device and a hybrid vehicle control method in which one of front wheels and rear wheels of a vehicle is driven by an engine and the other is driven by a motor generator. About.

  2. Description of the Related Art Conventionally, for the purpose of improving vehicle fuel efficiency, reducing exhaust gas, and the like, a hybrid vehicle that includes an engine composed of an internal combustion engine and a motor generator as power sources and travels with one or both driving forces is known. (See Patent Document 1).

Such a hybrid vehicle generally has an engine and a motor generator provided in parallel on one of the front wheels and the rear wheels, and when a sudden torque is required, such as when starting, or when traveling in a city or in a traffic jam As described above, when the vehicle travels at a low speed, the motor is mainly driven, and when the vehicle travels at a low load, the engine is mainly driven. When there is a large acceleration request, both the engine and the motor are driven. During deceleration, the power input from the drive wheels is transmitted to the motor generator, which is operated as a generator, and the regenerative energy is charged as electric energy to the in-vehicle battery.
JP 2001-105908 A

  By the way, in the hybrid vehicle, there is a type in which one of the front wheels and the rear wheels is driven by an engine and the other is driven by a motor generator in addition to the above-described type. This type also basically has the same function as the type in which the engine and the motor generator are provided in parallel on one of the front wheels and the rear wheels described above, but there is a problem when this type of vehicle runs on a curve. .

  That is, in this type of hybrid vehicle in which the driving wheels are front and rear, when the traveling mode by the engine and the traveling mode by the motor generator are changed to each other when traveling on a predetermined curve, the driving unit is switched back and forth. . For this reason, the force vector due to the driving torque loaded on the vehicle changes. That is, if acceleration or deceleration control is performed with the steering wheel turned off, the driving method may change regardless of the steering angle of the steering wheel, and the behavior of the vehicle may be disturbed.

  As a countermeasure, in this type of hybrid vehicle having driving wheels at the front and rear, a control method is generally considered in which acceleration / deceleration control and shift control are not performed during vehicle curve traveling. Sometimes, there is a problem that high-precision traveling control cannot be realized.

  The present invention has been made in view of the above points, and in a hybrid vehicle control device of the type in which one of the front wheels and the rear wheels is driven by an engine and the other is driven by a motor generator, the vehicle The object is to realize highly accurate traveling control without disturbing the behavior.

In order to solve the above problems, the present invention provides a control device for a hybrid vehicle having an engine connected to one of the front wheels and the rear wheel and a motor connected to a wheel different from the engine as a drive source. An HV control unit that performs control for switching a travel mode for setting a driving state of the drive source of the vehicle based on a predetermined switching condition, and the HV control unit includes a case where the vehicle is turning. There is provided a hybrid vehicle control device characterized in that the switching condition is different depending on the case where it is not.

According to such a hybrid vehicle control device, the driving mode switching conditions differ between when the vehicle is turning and when it is not.
Further, the present invention provides a control method in a hybrid vehicle using an engine connected to one of the front wheels and the rear wheel and a motor connected to a wheel different from the engine as a driving source, and a predetermined switching Based on a condition, control is performed to switch a driving mode for setting a driving state of the driving source of the vehicle, and the switching condition is made different depending on whether the vehicle is turning or not. A hybrid vehicle control method is provided.

  According to such a hybrid vehicle control method, the driving mode switching conditions differ between when the vehicle is turning and when it is not.

According to the hybrid vehicle control device and the hybrid vehicle control method of the present invention, travel control is performed in consideration of turning of the vehicle.
For this reason, disturbance of the behavior of the vehicle can be prevented or suppressed. In addition, since traveling control is executed even when the vehicle is traveling on a curve, highly accurate traveling control can be realized.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
In the present embodiment, the hybrid vehicle control device of the present invention is applied to a hybrid vehicle (hereinafter simply referred to as “vehicle”) in which the front wheels are driven by an engine composed of an internal combustion engine and the rear wheels are driven by a motor generator. Is. FIG. 1 is a system configuration diagram showing the configuration of the hybrid vehicle control device according to the present embodiment.

  The hybrid vehicle control device includes an engine 1 that drives the front wheels 21 and a motor generator 2 that drives the rear wheels 22 as vehicle drive sources. The engine 1 can be temporarily stopped in a predetermined operation state. On the other hand, the motor generator 2 can function as a motor when the vehicle is driven, and can function as a generator when the vehicle is braked.

  A mechanical oil pump 23, a torque converter 24, a forward / reverse clutch 25 (clutch mechanism), a continuously variable transmission 26, and a reduction gear 27 are sequentially connected to one output shaft of the engine 1, and the output of the reduction gear 27 is output. It is transmitted to the left and right front wheels 21 via the differential 28.

  The torque converter 24 is for smoothly transmitting the power of the engine 1 to the axle. The pump impeller connected to the output shaft of the engine 1, the turbine liner connected to the output shaft of the torque converter 24, and the like And a stator that changes the flow of oil inside and a lock-up clutch that fastens the pump impeller and the turbine liner according to predetermined conditions.

  The forward / reverse clutch 25 includes a planetary gear, and includes a sun gear coupled to the output shaft of the torque converter 24, a carrier coupled to the input shaft of the continuously variable transmission 26, and a ring gear coupled to the brake.

The continuously variable transmission 26 includes a primary pulley 26a connected to the input shaft, a secondary pulley 26b connected to the output shaft, and a belt 26c stretched between the pulleys, and torque transmitted from the input shaft. Is transmitted to the output shaft. The shift control of the continuously variable transmission 26 is performed by hydraulic control by the hydraulic control device 29. The hydraulic control device 29 performs hydraulic control using hydraulic fluid pumped from a predetermined hydraulic source by the mechanical oil pump 23 or the electromagnetically driven electric oil pump 30. The groove width of the primary pulley 26a is changed by hydraulic control, while the clamping pressure of the secondary pulley 26b on the belt 26c is held by hydraulic control, and the engagement diameter of the belt 26c in each pulley is changed, thereby changing the input shaft. The gear ratio, which is the ratio of the number of rotations between the motor and the output shaft, is continuously changed. The electric oil pump 30 is provided separately from the mechanical oil pump 23 so that hydraulic oil can be supplied from a hydraulic source even when the engine 1 is stopped. That is, the hydraulic pressure is maintained so that the hydraulic pressure of each pulley of the continuously variable transmission 26 does not decrease even when the engine 1 is stopped.

  The reduction gear 27 matches the rotational direction of the axle with the rotational direction of the output shaft of the engine 1. That is, in the continuously variable transmission 26, the rotation direction is reversed between the input shaft and the output shaft, but the reduction gear 27 further reverses the rotation direction of the reversed output shaft to rotate the input shaft. To match.

  The differential 28 transmits the output of the reduction gear 27 to the accelerator shafts connected to the left and right front wheels 21 and absorbs the rotational difference between the left and right front wheels 21 when the vehicle travels a curve, thereby realizing a smooth running of the vehicle. Let

  The other output shaft of the engine 1 is connected in parallel with a motor generator 31 for power generation and an alternator 32 that is a vehicle AC generator via a predetermined rotating belt. The motor generator 31 generates power using the power of the engine 1 and supplies power to the motor generator 2 or charges each battery described later. The electric power generated by the alternator 32 is supplied to various auxiliary machines such as an air conditioner and a lighting device of a vehicle (not shown). When surplus electric power is generated, the electric power is supplied to an auxiliary battery 33 for auxiliary equipment and charged. Is done.

  Furthermore, an HV battery 34 for supplying electric power to the motor generator 2 as necessary is provided. An inverter unit 37 including a DC-DC converter 35 and various inverters 36 is provided in the center of the motor generator 2, the motor generator 31, the alternator 32 and the HV battery 34. The electric power generated by each generator and the electric power supplied from each battery are supplied to each controlled object by being transformed to a predetermined voltage via the inverter unit 37, and the electric power generated by each generator is It can be used to charge each battery.

  Each control object is controlled by an electronic control unit (hereinafter referred to as “ECU”). That is, engine control is performed by an engine ECU (hereinafter referred to as “engine ECU”) 41, and transmission control is performed by a continuously variable transmission ECU (hereinafter referred to as “CVTECU”) 42, which is used for suspension of brakes and the like. ECU (hereinafter referred to as “skid ECU”) 43 performs brake control, traction control, and the like, and HV battery ECU (hereinafter referred to as “battery ECU”) 44 performs charge / discharge control of HV battery 34. A plurality of driving modes (to be described later) are switched by a hybrid control ECU (hereinafter referred to as “HVECU”) 45 provided in the center, and engine driving (front wheel driving), motor driving (rear wheel driving), and four wheel driving are performed. Various arithmetic processes for braking / regeneration and the like are performed, and operation commands are output to the ECUs to realize desired traveling control. In the present embodiment, HVECU 45 (corresponding to “HV control unit”) also functions as a motor control unit that controls driving of motor generator 2.

Each of the ECUs described above is an independent electronic control unit that is configured around a calculation unit including a microcomputer. Each ECU includes a CPU (Central Processing Unit) that executes various arithmetic processes, a ROM (Read Only Memory) that stores various control arithmetic programs and data, and a RAM (Random) that stores numerical values and flags of arithmetic processes in a predetermined area. Access Memory), EEPROM (Electronically Erasable and Programmable Read Only Memory), which is a non-volatile storage device that stores the results of arithmetic processing, and A / D (Analog / Digital) that converts an input analog signal into a digital signal It includes a converter, an input / output interface through which various digital signals are input / output, a timer for timing used in the calculation process, and a bus line to which these devices are connected. Each ECU has a built-in communication control unit for performing communication processing with each other via a communication line so that data can be transmitted and received with each other.

  The engine ECU 41 incorporates a signal input / output unit that takes in output signals from various sensors that detect the state of the engine 1 and outputs drive signals to various actuators provided in the engine 1. That is, the signal input / output unit of the engine ECU 41 includes an accelerator opening sensor that detects the amount of depression of the accelerator pedal, an air flow meter that detects the amount of intake air, an intake air temperature sensor that detects the temperature of intake air, and an open throttle valve. Sensors and switches such as a throttle opening sensor that detects the degree of water, a water temperature sensor that detects the cooling water temperature, an engine speed sensor that detects the engine speed, a vehicle speed sensor that detects the vehicle speed from the rotation of the vehicle drive shaft, and an ignition switch An injector provided for each cylinder of the engine 1, an igniter that generates a high voltage for ignition, a fuel pump that pumps fuel from the fuel tank and supplies it to the injector, and a throttle provided in the intake pipe of the engine 1 Engines such as throttle drive motors for opening and closing valves Various actuators for control is connected. The engine ECU 41 performs a predetermined engine control process for generating a driving torque necessary for driving the vehicle in accordance with a control program stored in the ROM.

  The CVT ECU 42 incorporates a signal input / output unit for taking in output signals from various sensors for detecting the state of the continuously variable transmission 26 and outputting drive signals to various actuators provided in the continuously variable transmission 26. ing. That is, the signal input / output unit of the CVTECU 42 includes an input shaft rotational speed sensor that detects the rotational speed of the input shaft of the continuously variable transmission 26, and an output shaft rotational speed that detects the rotational speed of the output shaft of the continuously variable transmission 26. Sensor, vehicle speed sensor that detects the vehicle speed from the rotation of the vehicle drive shaft, oil temperature sensor that detects the temperature of the hydraulic oil, belt clamping pressure sensor that detects the hydraulic pressure (belt clamping pressure) in the secondary pulley, brake operation of the driver Sensors such as a stop lamp switch for detection and a shift position sensor for detecting the current shift position are connected, a shift solenoid for controlling the shift of the continuously variable transmission 26, and a belt slip of the continuously variable transmission 26 is suppressed. In order to achieve this, a belt clamping solenoid that controls the clamping pressure of the belt, a line pressure control software that controls the line pressure that is the source pressure of the hydraulic pressure used for shift control. Maytansinoid, various actuators for lockup pressure solenoid, such shift control for operating the engagement force of the lock-up clutch to be described later to enter into input and output shaft of the torque converter 24 is connected. The CVTECU 42 performs a predetermined shift control process according to a control program stored in the ROM. In other words, the CVTECU 42 performs feedback control using a deviation between the target speed ratio that is the target speed ratio and the actual speed ratio that is the current speed ratio. Specifically, by setting the control amount to be proportional to the difference between the target gear ratio and the actual gear ratio, proportional control that gradually brings the actual gear ratio closer to the target gear ratio, or a steady deviation that cannot be eliminated only by proportional control is reduced. PID control including integral control for the purpose and differential control for reducing the time constant to quickly bring the actual gear ratio closer to the target gear ratio, and calculating control instruction values to be output to each hydraulic actuator for gear shifting control To do. In the hydraulic control device 29, each hydraulic actuator is driven based on this control instruction value to control the operation of each valve, and the amount of hydraulic oil supplied to and discharged from the primary pulley 26a and the secondary pulley so as to obtain the target gear ratio. The pressure (belt clamping pressure) of the hydraulic oil supplied to and discharged from 26b is adjusted.

  The skid ECU 43 includes a master cylinder pressure sensor that detects a hydraulic pressure of a master cylinder of a brake device such as an anti-lock brake (ABS), a steering sensor that detects a steering angle of a steering, a brake stroke sensor that detects a brake depression amount, a vehicle Sensors such as a yaw rate sensor for detecting the yaw rate are connected, and a brake actuator for generating a hydraulic pressure of the master cylinder to perform brake control is connected. This skid ECU 43 is used for brake control during vehicle braking, vehicle stabilization control for maintaining vehicle running stability during curve driving, and acceleration slip of the drive wheels in accordance with a control program stored in the ROM. Perform traction control.

  Sensors such as a voltage sensor for detecting the charging voltage of the HV battery 34 are connected to the battery ECU 44. The battery ECU 44 outputs the current charge amount of the HV battery 34 to the HVECU 45 based on the detection signal of the sensor, or the voltage of the voltage to be supplied to the inverter unit 37 to the HV battery 34 based on a command from the HVECU 45. Output a supply command.

  The HVECU 45 is communicably connected to another ECU via the communication line described above, acquires necessary information from the other ECU, outputs a control command for travel control to the other ECU, and The motor generator 2 is driven and controlled as necessary. The HVECU 45 is also connected to the inverter unit 37 via a predetermined signal line, and controls various inverters 36 and the like. The drive current supplied from the HV battery 34 to the motor generator 2 or the motor generator 2 The regenerative current regenerated to the HV battery 34 is adjusted. The HVECU 45 switches a plurality of modes, which will be described later, on the basis of a predetermined mode switching condition for vehicle travel control, outputs an operation command to the engine ECU 41 and the CVTECU 42 corresponding to each mode, and controls the motor generator 2. To do.

Next, an outline of engine control and shift control will be described.
The engine ECU 41 first determines the accelerator opening that represents the driver's acceleration / deceleration request, the axle torque that is calculated based on the vehicle speed and load that represents the actual running state of the vehicle, Based on the requested axle torque input from the ECU, a target drive torque is calculated.

  Then, the engine ECU 41 integrates the vehicle speed detected by the vehicle speed sensor with respect to the drive torque, that is, the axle rotation speed, and calculates the power necessary to extract the drive torque from the engine. Then, the engine torque and the engine speed for realizing this power are determined based on the condition that the fuel efficiency becomes the best. This condition is performed by referring to a control map (not shown) showing the relationship between the engine torque and the engine speed in association with the fuel efficiency and selecting an operating point along the optimum fuel efficiency line. The engine ECU 41 sets the engine torque calculated at this time as the target engine torque, and controls each actuator so that the current engine torque approaches the target engine torque.

  The CVTECU 42 calculates a target input shaft rotational speed that is a target rotational speed of the input shaft of the continuously variable transmission 26 based on the engine rotational speed corresponding to the target engine torque, and uses the target input shaft rotational speed as an output shaft. Divide by the number of revolutions to calculate the target gear ratio. The CVTECU 42 controls each actuator of the hydraulic control device 29 so that the current gear ratio approaches the target gear ratio.

Next, a vehicle travel control method in the hybrid vehicle control apparatus of the present embodiment will be described. FIG. 2 is an explanatory diagram showing the mode of the driving mode of the vehicle, where (A) shows the 4WD mode, (B) shows the engine mode, (C) shows the EV mode, and (D) shows the regeneration mode, respectively. Represents.

  In this hybrid vehicle control device, four traveling control modes are set, and the HVECU 45 selects an appropriate traveling control mode based on the traveling state of the vehicle and the charging state of the HV battery 34 and the like.

  Here, the 4WD mode is a traveling mode in which both the engine 1 and the motor generator 2 are driven to travel, the forward / reverse clutch 25 is engaged, and both the front wheels 21 and the rear wheels 22 are driven. This 4WD mode is selected when the vehicle is accelerating, or when the driving wheel is idle in the engine mode or EV mode.

  The engine mode is a mode in which the motor generator 2 is stopped and only the engine 1 is driven to travel, the forward / reverse clutch 25 is engaged, and only the front wheels 21 are driven. This engine mode is selected when the engine 1 is started or when the vehicle is in an operating region where engine efficiency is particularly high.

  The EV mode is a mode in which the engine 1 is stopped and only the motor generator 2 is driven to travel, and the forward / reverse clutch 25 is disengaged and only the rear wheels 22 are driven. This EV mode is selected when the vehicle is in a driving region where the engine efficiency is poor, such as when the vehicle starts at a relatively low load, or when traveling at a low speed or down a gentle slope.

  The regeneration mode is a mode in which the motor generator 2 is regenerated and the HV battery 34 is charged. The engine 1 is stopped, the forward / reverse clutch 25 is released, and only the rear wheel 22 is driven. This regeneration mode is selected when the amount of charge of the HV battery 34 is low.

  When the vehicle travels substantially linearly, transition between modes according to the traveling state of the vehicle is permitted. However, when the vehicle travels a curve with a predetermined curvature and length, Transition between is limited. That is, when the steering angle of the steering becomes equal to or greater than a predetermined set value, traveling control that is set in advance for the operation of the steering is performed. In the following description, this travel control is also referred to as “travel control during steering operation”. Note that the “setting value” here is set in advance to a steering angle that requires switching of traveling control by experiment or the like, but may be changed according to the vehicle speed (the same applies hereinafter). For example, when the vehicle speed is high, the set value is decreased, and when the vehicle speed is low, the set value is increased.

  FIG. 3 is a control map showing whether or not to allow transition between modes when the vehicle turns on a predetermined curve. In the figure, a solid line arrow represents a transition permission, and a broken line arrow represents a transition prohibition.

  That is, in a normal control state where the vehicle is not turning (when the steering angle of the steering is less than a preset value), for example, the following travel mode switching control is performed.

When the vehicle engine is started or stopped, the engine mode is selected to warm up the engine 1 or charge the HV battery 34.
When the vehicle starts or runs backward, the EV mode is selected when the amount of charge of the HV battery 34 is sufficient, and driving is started by driving the motor generator 2. On the other hand, when the charging amount of the HV battery 34 is insufficient, the engine 1 is simultaneously driven to enter the 4WD mode, and the motor generator 2 is driven to start running and charge the HV battery 34.

  When the vehicle travels at a low load or goes down a gentle slope, for example, when the vehicle travels lightly in a driving region where engine efficiency is poor, the vehicle is switched to the EV mode to reduce fuel consumption. At this time, when the charge amount of the HV battery 34 decreases, the engine 1 is simultaneously driven to switch to the 4WD mode, and the HV battery 34 is charged while continuing to run by driving the motor generator 2.

  Furthermore, when the vehicle shifts to steady running, which is a driving region where engine efficiency is good, the mode is switched to the engine mode. At this time, when the charge amount of the HV battery 34 decreases, the output of the engine 1 is increased and the HV battery 34 is charged.

  Further, when the vehicle accelerates, the mode is switched to the 4WD mode in order to apply the driving force of the motor generator 2. This 4WD mode is also switched when the vehicle travels uphill or travels on a low μ road.

Further, when the vehicle shifts to decelerating traveling, for example, when the accelerator pedal is turned off, the HV battery 34 is charged by switching to the regeneration mode.
When the vehicle shifts to turning, for example, the following traveling mode switching control is performed.

  That is, when the vehicle shifts to a turning state while traveling in the 4WD mode, and the steering angle exceeds the set value, switching to any of the engine mode, the EV mode, and the regeneration mode is prohibited, and the 4WD mode is maintained. Is done.

  In addition, when the vehicle shifts to turning while traveling in the engine mode and the steering angle becomes equal to or larger than the set value, switching to the 4WD mode is permitted based on a predetermined mode switching condition. Switching to mode and regenerative mode is prohibited.

  In addition, when the vehicle shifts to turning while traveling in the EV mode and the steering angle becomes equal to or greater than the set value, switching to the 4WD mode and the regeneration mode is permitted based on the mode switching condition. Switching to engine mode is prohibited.

  Furthermore, when the vehicle shifts to turning while traveling in the regenerative mode and the steering angle becomes equal to or greater than a predetermined set value, switching to the 4WD mode is permitted based on the mode switching condition, but the engine mode And switching to the EV mode is prohibited.

  As described above, switching to the 4WD mode is permitted only when the vehicle is traveling on a curve, and when the vehicle is in the 4WD mode in which the driving torque is distributed to the front and rear wheels, the wheel is loaded. This is because the driving torque is relatively small, and driving force is applied to both the front and rear wheels of the vehicle, so that stable traveling can be realized.

  FIG. 4 is an explanatory diagram illustrating an example of a control map of vehicle travel control corrected according to the steering angle. (A) shows the relationship between the accelerator opening and the driving torque, the horizontal axis represents the accelerator opening, and the vertical axis represents the driving torque. (B) shows the relationship between the vehicle speed and the accelerator opening, the horizontal axis represents the vehicle speed, and the vertical axis represents the accelerator opening. In these drawings, the alternate long and short dash line represents a control map used in normal traveling control, and the solid line represents a corrected control map used for traveling control during steering operation.

As shown in FIG. 5A, when the steering angle becomes equal to or larger than a set value, the target torque set for the same accelerator opening during normal traveling is corrected so as to be small. That is, the driving torque does not easily increase even when the accelerator is depressed, and the safety and stability when traveling on a curve are ensured.

As a result, as shown in FIG. 5B, when the steering angle becomes equal to or greater than the set value, the vehicle speed becomes smaller than the accelerator opening during normal traveling.
FIG. 5 is an explanatory diagram illustrating an example of a control map representing a guard value of the target torque. (A) shows the relationship between the vehicle speed and the target torque, the horizontal axis represents the vehicle speed, and the vertical axis represents the target torque. (B) shows the relationship between the accelerator opening and the target torque, the horizontal axis represents the accelerator opening, and the vertical axis represents the target torque. In these figures, the alternate long and short dash line represents the target torque, and the solid line represents the guard value of the target torque.

  In the present embodiment, a guard value that defines the upper limit of the target torque is provided so that the driving torque does not become too large during steering operation so that the behavior of the vehicle is not disturbed. Therefore, when the target torque becomes equal to or higher than the guard value, the target torque is fixed to the guard value.

As shown in FIG. 6A, the increase of the drive torque is limited as the vehicle travels on a sharp curve by lowering the guard value of the target torque as the steering angle increases.
Also, as shown in FIG. 4B, the target torque that is set increases as the accelerator opening increases. However, the driving torque during high-speed traveling is reduced by lowering the guard value of the target torque as the vehicle speed increases. Rise is limited.

  FIG. 6 is an explanatory diagram showing an example of a control map of the target torque distributed to the newly driven wheels when shifting from the engine mode or EV mode to the 4WD mode. In the figure, the horizontal axis represents the time since the mode switching, and the vertical axis represents the target torque.

  In other words, the target torque distributed to the rear wheels when shifting from the engine mode to the 4WD mode, and the target torque distributed to the front wheels when shifting from the EV mode to the 4WD mode are smoothly swept instead of starting up at once. Let me up. As a result, sudden torque fluctuations are prevented from occurring on each wheel, and the behavior of the vehicle is kept stable.

  FIG. 7 is an explanatory diagram showing an example of distribution of the target torque at the time of each mode switching. In the figure, the horizontal axis represents the passage of time, and the vertical axis represents the target torque. The solid line represents the target torque distributed to the front wheels, and the alternate long and short dash line represents the target torque distributed to the rear wheels.

Thus, in order to realize a certain driving torque, the target torque applied to each of the front wheels and the rear wheels is distributed.
Next, a flow of vehicle travel control processing in the hybrid vehicle control apparatus of the present embodiment will be briefly described. FIG. 8 is a flowchart showing the flow of processing executed by the HVECU and other ECUs. Hereinafter, the flow of this process will be described using step numbers (hereinafter referred to as “S”).

  First, the HVECU 45 calculates the current steering angle based on the output from the steering sensor (S110). Then, it is determined whether or not the steering angle is equal to or greater than the set value described above (S120).

At this time, if the steering angle is determined to be equal to or larger than the set value because the vehicle has traveled a predetermined curve (S120: YES), the shift to the corrected travel control set for the steering operation is performed ( S130), the travel mode is selected based on the control map shown in FIG. 3 (S140). Then, a control command for realizing the travel mode is output to each ECU, that is, the ECU that requires the control command among the engine ECU 41, the CVTECU 42, the skid ECU 43, the battery ECU 44, and the like (S150). At the same time, if it is necessary to control the motor generator 2 in the 4WD mode, EV mode, regenerative mode, etc., this is controlled (S160).

  Then, based on the output from the steering sensor, it is determined whether or not the steering angle is equal to or less than the second set value described above (S170). At this time, when it is determined that the vehicle has passed the curve and returned from turning, and the steering angle is determined to be equal to or less than the second set value described above (S170: YES), whether or not the state has been continued for a set time. Is determined (S180). If a negative determination is made in S170, S180, the process returns to S130. Here, a value equal to or smaller than the above set value is set as the second set value.

  In S180, when it is determined that the state in which the steering angle is equal to or smaller than the second set value has been continued for the set time (S180: YES), the normal travel control without performing the corrected travel control is restored. (S190). Then, a travel mode is selected under normal travel control conditions (S200), and a control command for realizing the travel mode is output to each ECU (S210). At the same time, if it is necessary to control the motor generator 2 such as the 4WD mode, the EV mode, or the regeneration mode, this is controlled (S220).

  On the other hand, other ECUs such as the engine ECU 41, the CVTECU 42, the skid ECU 43, and the battery ECU 44 perform normal traveling control on each control target (actuator and the like) when performing normal traveling such as straight traveling, right turn, and left turn. Perform (S310).

  Then, based on S150, it is determined whether or not a control command for shifting to one of the travel modes during the steering operation is received from HVECU 45 (S320). At this time, if it is determined that a control command has not been received (S320: NO), normal traveling control is continued. On the other hand, if it is determined that a control command has been received (S320: YES), control for shifting to a predetermined travel mode at the time of steering operation is performed (S330).

  Then, based on S210, it is determined whether or not a control command for shifting to the normal travel mode is received from HVECU 45 (S340). At this time, if it is determined that the control command has not been received (S340: NO), the travel control during the steering operation is continued. On the other hand, if it is determined that the control command has been received (S340: YES), the vehicle is returned to normal traveling control (S350).

  As described above, in the hybrid vehicle control device according to the present embodiment, when the steering angle of the steering becomes equal to or greater than a predetermined set value that affects the behavior of the vehicle, Pre-set travel control is performed for the steering operation. That is, when the vehicle is traveling on a curve, the control amount is corrected in consideration of the steering angle of the steering and the travel mode is selected, so that the disturbance of the behavior of the vehicle can be prevented or suppressed. In addition, since the travel control is executed without stopping even when the vehicle is traveling on a curve, highly accurate travel control can be realized.

  In the above embodiment, the steering angle of the steering is detected by the steering sensor. However, the means for detecting the steering angle may be a single sensor or based on a signal from the sensor or the like. A dedicated electronic control device that calculates the steering angle may be used. In addition, when normal detection of the steering angle cannot be performed, for example, when the sensor for detecting the steering angle is abnormal, it is preferable not to perform the shift to the travel control during the steering operation.

In the above embodiment, the state in which the vehicle is turning on a curve is determined by detecting the steering angle of the steering. For example, by detecting the lateral acceleration of the vehicle by a G sensor or the like, It may be determined based on vehicle travel information by a navigation system.

It is a system configuration figure showing composition of a hybrid vehicle control device. It is explanatory drawing showing the aspect of the driving mode of a vehicle. It is a control map showing the permission of the transition between each mode at the time of a vehicle turning on a predetermined curve. It is explanatory drawing showing the example of the control map of the vehicle travel control correct | amended according to the steering angle. It is explanatory drawing showing the example of the control map showing the guard value of target torque. It is explanatory drawing showing the example of the control map of the target torque distributed to the wheel by the side of newly driven when transfering from engine mode or EV mode to 4WD mode. It is explanatory drawing showing the example of distribution of the target torque at the time of each mode switching. It is a flowchart showing the flow of the process which HVECU and other ECU perform.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Engine 2 Motor generator 21 Front wheel 22 Rear wheel 25 Forward / backward clutch 26 Continuously variable transmission 29 Hydraulic control device 31 Motor generator 32 Alternator 33 Auxiliary battery 34 HV battery 37 Inverter unit 41 Engine ECU
42 CVTECU
43 Skid ECU
44 Battery ECU
45 HVECU

Claims (21)

A control device in a hybrid vehicle having an engine connected to one of the front wheel and the rear wheel and a motor connected to a wheel different from the engine as a drive source,
An HV control unit that performs control for switching a driving mode for setting a driving state of the driving source of the vehicle based on a predetermined switching condition;
The hybrid vehicle control device, wherein the HV control unit changes the switching condition between when the vehicle is turning and when it is not.   The HV control unit switches to another travel mode when the travel mode of the vehicle is a 4WD mode in which both the engine and the motor are driven to travel and the vehicle is turning. The hybrid vehicle control device according to claim 1, wherein switching of the vehicle is prohibited.   The HV control unit drives both the engine and the motor when the traveling mode of the vehicle is an engine mode in which only the engine is driven and the vehicle is turning. The hybrid vehicle control device according to claim 1, wherein switching to the 4WD mode of traveling is permitted.   The HV control unit includes an EV mode in which the vehicle travel mode is an engine mode in which only the engine is driven to travel, and the vehicle is traveling in a turn when the vehicle is traveling in a turn. The hybrid vehicle control device according to claim 1, wherein switching to a regeneration mode in which regeneration is performed with the engine stopped is prohibited.   The HV control unit drives both the engine and the motor when the traveling mode of the vehicle is an EV mode in which only the motor is driven and the vehicle is turning. 2. The hybrid vehicle control device according to claim 1, wherein switching to a 4WD mode in which the vehicle is running or a regeneration mode in which regeneration is performed while the engine is stopped is permitted.   When the vehicle travel mode is an EV mode in which the vehicle travels by driving only the motor and the vehicle is turning, the HV control unit travels by driving only the engine. 2. The hybrid vehicle control device according to claim 1, wherein switching to the engine mode is prohibited.   When the vehicle travel mode is a regeneration mode in which regeneration is performed with the engine stopped, and the vehicle is turning, both the engine and the motor The hybrid vehicle control device according to claim 1, wherein switching to a 4WD mode in which the vehicle is driven is allowed.   The HV control unit drives only the motor when the vehicle travel mode is a regeneration mode in which regeneration is performed with the engine stopped, and the vehicle is turning. The hybrid vehicle control device according to claim 1, wherein switching to an EV mode for traveling and an engine mode for driving only the engine is prohibited.   The HV control unit performs control to switch the traveling mode under a switching condition when the vehicle is not turning, when the vehicle returns from turning, or the state in the middle of returning continues for a preset time. The hybrid vehicle control device according to claim 1.   The HV control unit performs regeneration while functioning the engine brake while the engine is stopped when the traveling mode of the vehicle is the 4WD mode and the vehicle is turning. The hybrid vehicle control device according to claim 2, wherein switching to the 4WD regeneration mode is permitted.   5. The engine brake function according to claim 4, wherein the HV control unit functions an engine brake when prohibiting switching from the engine mode to the regeneration mode when the accelerator of the vehicle is not depressed. Hybrid vehicle control device.   The HV control unit switches to the 4WD mode when the driving mode of the vehicle is the EV mode and the idling of the motor-driven wheels is detected when the vehicle is turning. The hybrid vehicle control device according to claim 5, wherein:   The HV control unit switches to the 4WD mode when the driving mode of the vehicle is the engine mode and the idling of the motor-driven wheel is detected when the vehicle is turning. The hybrid vehicle control device according to claim 3. A control method in a hybrid vehicle using an engine connected to one of the front wheels and the rear wheel and a motor connected to a wheel different from the engine as a drive source,
Based on a predetermined switching condition, a control for switching a driving mode for setting a driving state of the driving source of the vehicle is performed,
The hybrid vehicle control method, wherein the switching condition is made different between when the vehicle is turning and when it is not.   When the traveling mode of the vehicle is a 4WD mode in which both the engine and the motor are driven to travel and the vehicle is turning, prohibiting switching to another traveling mode. The hybrid vehicle control method according to claim 14.   4WD mode in which the driving mode of the vehicle is an engine mode in which only the engine is driven and when the vehicle is turning, and both the engine and the motor are driven. The hybrid vehicle control method according to claim 14, wherein switching to is permitted.   When the driving mode of the vehicle is an engine mode in which only the engine is driven and the vehicle is turning, the EV mode in which only the motor is driven and the engine are stopped. The hybrid vehicle control method according to claim 14, wherein switching to a regeneration mode in which regeneration is performed in a state is prohibited.   The vehicle travel mode is an EV mode that travels by driving only the motor, and when the vehicle is turning, the 4WD mode that travels by driving both the engine and the motor. The hybrid vehicle control method according to claim 14, wherein switching to a regeneration mode in which regeneration is performed with the engine stopped is permitted.   When the travel mode of the vehicle is an EV mode that travels by driving only the motor, and the vehicle is turning, the mode is switched to an engine mode that travels by driving only the engine. The hybrid vehicle control method according to claim 14, wherein the hybrid vehicle control method is prohibited. When the traveling mode of the vehicle is a regenerative mode in which regeneration is performed with the engine stopped, and the vehicle is turning, the vehicle travels by driving both the engine and the motor. The hybrid vehicle control method according to claim 14, wherein switching to the 4WD mode is permitted. When the vehicle travel mode is a regeneration mode in which regeneration is performed with the engine stopped, and the vehicle is turning, the EV mode in which the vehicle is driven by driving only the motor and the vehicle The hybrid vehicle control method according to claim 14, wherein switching to an engine mode in which only the engine is driven to travel is prohibited.

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