JP2011239605A - Controller of vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve efficiency by suppressing energy consumption during carrying out a cruise control, in a vehicle capable of carrying out the cruise control controlling a vehicle speed at a target speed.SOLUTION: The energy consumption is reduced as the result of lowering an energy consumption and suppressing the electric path passage part of an energy by putting the vehicle into a coasting state within constant-speed traveling control ranges (concretely, the ranges of the allowable lower-limit value M≤"an acceleration α"≤the allowable upper-limit value N, and the allowable lower-limit value m≤"the vehicle speed V"≤the allowable upper-limit value) in case of the cruise control, noting that a driver desires a continuous constant speed traveling in case of the cruise control and a braking force by a regeneration need not be generated.

Description

  The present invention relates to a control device for a vehicle such as a hybrid vehicle or an electric vehicle equipped with an electric motor that outputs driving power.

  In recent years, from the viewpoint of environmental protection, it has been desired to reduce exhaust gas emissions from engines (internal combustion engines) mounted on vehicles and to improve fuel consumption rate (fuel consumption). Has been put into practical use, and electric vehicles (EV vehicles) that do not use fuel such as gasoline have been put into practical use.

  The hybrid vehicle includes an engine such as a gasoline engine or a diesel engine, and an electric motor (for example, a motor generator or a motor) that performs power generation by the output of the engine or assists engine output by being driven by electric power of a battery (power storage device), Either one or both of the engine and the electric motor is used as a travel drive source.

  In the hybrid vehicle, the operating range (specifically, driving or stopping) of the engine and the electric motor is controlled based on the vehicle speed and the accelerator opening. For example, in a region where the engine efficiency is low, such as when starting or running at a low speed, the engine is stopped and the drive wheels are driven by the power of only the electric motor. Further, during normal traveling, control is performed such that the engine is driven and the driving wheels are driven by the power of the engine. Further, at the time of high load such as full-open acceleration, in addition to engine power, control is performed such that power is supplied from the battery to the electric motor and the power from the electric motor is added as auxiliary power.

  As a general vehicle control, a cruise control that automatically controls a vehicle speed to a target vehicle speed is known (for example, see Patent Document 1). In cruise control, for example, the vehicle speed is recognized by a sensor or the like, and the control throttle opening / closing control (in the case of a hybrid vehicle, electronic throttle control) is performed so that the vehicle speed becomes a target vehicle speed (a vehicle speed within an allowable range). This is a technology that performs engine control that repeats “open” and “close”. Such cruise control is also implemented in electric vehicles.

JP 2000-295714 A JP 2006-321466 A

  As described above, in a hybrid vehicle (EV vehicle), the vehicle speed is managed within the allowable vehicle speed range by repeatedly opening and closing the control throttle while monitoring the vehicle speed during cruise control. When in the “closed” state, regenerative torque (braking force equivalent to engine brakes for conventional vehicles) is generated according to the vehicle speed or acceleration. When such regenerative control is performed, the regenerative torque is applied in the N range (neutral range). When the vehicle speed decreases more quickly than when coasting, the time to open the control throttle (time to resume energy consumption: time to open the throttle valve for hybrid vehicles, power to the motor (motor) for EV vehicles) The supply time) becomes earlier and energy is consumed accordingly.

  The electric energy regenerated during cruise control is stored in the battery (power storage device) and can be reused. However, the efficiency of the electric path is not 100%, and energy loss occurs.

  The present invention has been made in consideration of such circumstances, and in a vehicle capable of executing cruise control for controlling the vehicle speed to the target vehicle speed, it is possible to suppress energy consumption during execution of cruise control and increase efficiency. The purpose is to realize control.

-Solving principle of the problem-The solving principle of the present invention taken to achieve the above object is that the driver desires continuous constant speed driving during cruise control, and it is necessary to generate braking force by regeneration. Focusing on this point, it is possible to reduce energy consumption by actively creating coasting conditions within the cruise control range during cruise control, thereby reducing energy consumption and suppressing energy passage through the electrical path. Like that.

-Solution-
Specifically, the present invention is applied to a vehicle equipped with an electric motor capable of outputting driving power and is premised on a vehicle control device capable of executing cruise control for controlling the vehicle speed to a target vehicle speed. In such a vehicle control device, it is a technical feature that the motor is operated with the output torque of the motor set to substantially zero on condition that the vehicle speed is within a constant speed travel management range during cruise control. . More specifically, on the condition that the control throttle is “closed” and the vehicle speed is within the constant speed travel management range during cruise control, the motor output torque is set to substantially zero and the motor is operated. Features.

  According to the present invention, when the vehicle speed is within the constant speed traveling management range (for example, the current vehicle speed is within the allowable vehicle speed range set with respect to the target vehicle speed) during cruise control, and there is no need for deceleration, the output of the motor By making the torque substantially zero (for example, electrically shutting off the electric motor (neutral state)) and actively making the coasting running state, the kinetic energy is utilized for vehicle running without regenerating. By such control, energy consumption can be reduced and the amount of energy passing through the electric path can be suppressed. Thereby, for example, in a hybrid vehicle, it is possible to improve fuel efficiency during cruise control.

  In the present invention, on the condition that the vehicle speed is within a predetermined allowable vehicle speed range (within a constant speed travel management range) at the time of cruise control, the output torque of the motor is set to substantially zero and the motor is operated. Good. Further, the motor may be operated with the output torque of the motor set to substantially zero on condition that the acceleration of the vehicle is within a predetermined allowable acceleration range (within a constant speed traveling management range) during cruise control. . The “acceleration” in the present invention includes deceleration (negative acceleration).

  Further, in the present invention, during cruise control, the output torque of the motor is set to substantially zero on condition that the vehicle speed is within a predetermined allowable vehicle speed range and the vehicle acceleration is within a predetermined allowable acceleration range. The electric motor may be operated. Thus, it is preferable in terms of controllability to manage the vehicle speed by combining the vehicle speed condition and the acceleration condition. The reason will be described below.

  First, when only “the vehicle acceleration is within a predetermined allowable acceleration range during cruise control” is used as a condition, for example, the vehicle acceleration (≠ 0) is constant even if the vehicle acceleration is within the allowable acceleration range. When this state continues, the vehicle speed increases (decreases), so the current vehicle speed may deviate significantly from the target vehicle speed. In order to eliminate these points, it is preferable to combine vehicle speed conditions (the condition that “the vehicle speed is within the allowable vehicle speed range”).

  In addition, when only the condition that “the vehicle speed is within a predetermined allowable vehicle speed range during cruise control” is the condition, the vehicle speed is within the allowable vehicle speed range. Until the vehicle reaches the upper limit of the allowable vehicle speed range, coasting is continued, so deceleration may be delayed. In order to eliminate such a point, it is preferable to combine an acceleration condition (a condition that “the vehicle acceleration is within the allowable acceleration range”).

  Here, in the present invention, a specific means for making the output torque of the electric motor substantially zero includes a means for electrically cutting off the electric motor from the electric system. In this case, as means for electrically shutting off the motor, for example, by turning off each switching element of the inverter provided for the motor (shutdown control), the motor is electrically shut off from the electric system. The structure of doing can be mentioned.

  According to the present invention, when there is no need for deceleration during cruise control, the output torque of the electric motor is set to substantially zero and the coasting state is set, so that energy consumption can be reduced. As a result, for example, in a hybrid vehicle, it is possible to improve fuel efficiency during cruise control.

It is a schematic structure figure showing an example of a vehicle to which the present invention is applied. It is a figure which shows a shift operation apparatus etc. It is a block diagram which shows the structure of control systems, such as ECU. It is a flowchart which shows an example of the control at the time of cruise control. It is a figure which shows together and shows the example (a) of the allowable acceleration range at the time of cruise control, and the example (b) of the allowable vehicle speed range at the time of cruise control. It is a figure which shows typically the change of the vehicle speed at the time of cruise control, and is a figure which shows together the example (a) by this invention control, and the example (b) by conventional control.

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

  FIG. 1 is a schematic configuration diagram showing an example of a hybrid vehicle to which the present invention is applied.

  The hybrid vehicle HV of this example is an FF (front engine / front drive) type hybrid vehicle, and is an engine 1, a first motor generator MG1 mainly functioning as a generator, and a first function mainly functioning as an electric motor (motor). 2 motor generator MG2, power split mechanism 3, reduction mechanism 4, counter drive gear 51, counter driven gear 52, final ring gear 53, differential device 54, drive wheel 6, shift operating device 7 (see FIG. 2), and ECU (Electronic The control apparatus for a vehicle according to the present invention is realized by a program executed by the ECU 100.

  The ECU 100 includes, for example, an HVECU, an engine ECU, a battery ECU, and the like, and these ECUs are connected so as to communicate with each other.

  Next, the engine 1, the motor generators MG1 and MG2, the power split mechanism 3, the reduction mechanism 4, the shift operation device 7, and each part of the ECU 100 will be described below.

-Engine-
The engine 1 is a known power device that outputs power by burning fuel such as a gasoline engine or a diesel engine, and includes a throttle opening (intake air amount) of a throttle valve 13 provided in an intake passage 12, fuel injection The operation state such as the amount and the ignition timing can be controlled. The rotation speed (engine rotation speed) of the crankshaft 11 that is the output shaft of the engine 1 is detected by an engine rotation speed sensor 101. The engine 1 is driven and controlled by the ECU 100.

  For controlling the throttle valve 13 of the engine 1, for example, an optimum intake air amount (target intake air amount) corresponding to the operating state of the engine 1 such as the engine speed and the accelerator pedal depression amount (accelerator opening) of the driver is obtained. Thus, electronic throttle control for controlling the throttle opening is employed. In such electronic throttle control, the throttle opening sensor 103 is used to detect the actual throttle opening of the throttle valve 13, and the actual throttle opening is the throttle opening (target throttle opening at which the target intake air amount is obtained). ), The throttle motor 14 of the throttle valve 13 is feedback-controlled. In such electronic throttle control, for example, the throttle opening may be controlled independently of the driver's accelerator pedal operation, for example, during idling or when performing cruise control to be described later.

  The output of the engine 1 is transmitted to the input shaft 21 via the crankshaft 11 and the damper 2. The damper 2 is a coil spring type transaxle damper, for example, and absorbs torque fluctuations of the engine 1. Note that an oil pump 22 is connected to the other end of the input shaft 21, and the oil pump 22 operates upon receiving the supply of the rotational torque of the input shaft 21.

-Motor generator-
The first motor generator MG1 is an AC synchronous generator including a rotor MG1R made of a permanent magnet that is rotatably supported with respect to the input shaft 21, and a stator MG1S around which a three-phase winding is wound. It functions as a generator and also functions as an electric motor (motor). Similarly, the second motor generator MG2 includes an AC synchronous generator including a rotor MG2R made of a permanent magnet rotatably supported by the input shaft 21 and a stator MG2S wound with a three-phase winding. And it functions as a generator while functioning as an electric motor (motor).

  As shown in FIG. 3, first motor generator MG <b> 1 and second motor generator MG <b> 2 are each connected to battery (power storage device) 300 via inverter 200. Inverter 200 is controlled by ECU 100, and regeneration or power running (assist) of each motor generator MG 1, MG 2 is set by the control of inverter 200. The regenerative power at that time is charged in the battery 300 via the inverter 200. In addition, driving power for each of the motor generators MG1 and MG2 is supplied from the battery 300 via the inverter 200.

-Power split mechanism-
The power split mechanism 3 meshes with an external gear sun gear S3 that rotates at the center of a plurality of gear elements, an external gear pinion gear P3 that revolves around the sun gear S3 while rotating around its periphery, and a pinion gear P3. A planetary gear mechanism having a ring gear R3 of an internal gear formed in a hollow ring shape and a planetary carrier CA3 that supports the pinion gear P3 and rotates through the revolution of the pinion gear P3. The planetary carrier CA3 is integrally connected to the input shaft 21 on the engine 1 side. Sun gear S3 is integrally connected to rotor MG1R of first motor generator MG1.

  The power split mechanism 3 transmits at least one driving force of the engine 1 and the second motor generator MG2 to the left and right drive wheels 6 via the counter drive gear 51, the counter driven gear 52, the final ring gear 53, and the differential device 54. .

-Reduction mechanism-
The reduction mechanism 4 is rotatably supported by a sun gear S4, which is an external gear that rotates at the center of a plurality of gear elements, and a carrier (transaxle case) CA4, and an external gear pinion gear P4 that rotates while circumscribing the sun gear S4. And a planetary gear mechanism having a ring gear R4 of an internal gear formed in a hollow annular shape so as to mesh with the pinion gear P4. The ring gear R4 of the reduction mechanism 4, the ring gear R3 of the power split mechanism 3, and the counter drive gear 51 are integrated with each other. Sun gear S4 is integrally connected to rotor MG2R of second motor generator MG2.

  The reduction mechanism 4 decelerates the driving force of at least one of the engine 1 and the second motor generator MG2 at an appropriate reduction ratio. The decelerated power is transmitted to the drive wheels 6 through the counter drive gear 51, the counter driven gear 52, the final ring gear 53, and the differential device 54.

-Shift operation device-
On the other hand, a shift operating device 7 as shown in FIG. 2 is arranged in the vicinity of the driver's seat of the hybrid vehicle HV. The shift operating device 7 is provided with a shift lever 71 so that it can be displaced. The shift operation device 7 of this example includes a drive range (D range) for forward travel, a brake range (B range) for forward travel with a large braking force (engine brake) when the accelerator is off, and a reverse range for reverse travel. (R range) and neutral neutral range (N range) are set, and the driver can displace the shift lever 71 to a desired range. These positions of the D range, B range, R range, and N range are detected by the shift position sensor 104. An output signal of the shift position sensor 104 is input to the ECU 100. Note that the parking position (P position) can be set by a separately arranged P switch.

-ECU-
ECU 100 is an electronic control device that controls engine 1 and motor generators MG1, MG2 in a coordinated manner, and includes a CPU, a ROM, a RAM, a backup RAM, and the like. The ROM stores various control programs, maps that are referred to when the various control programs are executed, and the like. The CPU executes arithmetic processing based on various control programs and maps stored in the ROM. The RAM is a memory that temporarily stores calculation results from the CPU, data input from each sensor, and the like. The backup RAM is a non-volatile memory that stores data to be saved when the engine 1 is stopped. is there.

  As shown in FIG. 3, the ECU 100 detects an engine speed sensor 101 that detects the speed (engine speed) of the crankshaft 11 that is the output shaft of the engine 1, and an accelerator pedal depression amount (accelerator opening). An accelerator opening sensor 102, a throttle opening sensor 103, a shift position sensor 104, a wheel speed sensor 105 that detects the rotational speed of the wheel, a brake pedal sensor 106 that detects a depression force (braking force) against the brake pedal, and cruise control A switch 107 is connected. Further, the ECU 100 is connected with a water temperature sensor for detecting the engine cooling water temperature, an air flow meter for detecting the intake air amount, a current sensor for detecting the charge / discharge current of the battery 300, a battery temperature sensor, and the like. A signal from each sensor is input to the ECU 100. The ECU 100 is connected to a throttle motor 14 that opens and closes a throttle valve 13 of the engine 1, a fuel injection device 15, an ignition device 16, and the like.

  Here, the vehicle speed V and the acceleration α can be obtained from the output signal of the wheel speed sensor 105. As for the vehicle speed V, a vehicle speed sensor may be mounted on the vehicle, and the vehicle speed V may be obtained from the sensor output signal. As for the acceleration α, an acceleration sensor for detecting the longitudinal acceleration of the vehicle may be mounted on the vehicle, and the acceleration α may be obtained from the sensor output signal, or may be calculated from the output signal of the vehicle speed sensor. It may be.

  The ECU 100 executes various controls of the engine 1 including the throttle opening control (intake air amount control), the fuel injection amount control, the ignition timing control, and the like based on the output signals of the various sensors described above. To do.

  Further, in order to manage the battery 300, the ECU 100 is based on the charge / discharge current integrated value detected by the current sensor, the battery temperature detected by the battery temperature sensor, and the like. (State of Charge), input limit Win and output limit Wout of the battery 300, and the like.

  Further, an inverter 200 is connected to the ECU 100. Inverter 200 includes an IPM (Intelligent Power Module) for controlling motor generators MG1 and MG2. Each IPM is constituted by a plurality of (for example, six) semiconductor switching elements (for example, an IGBT (Insulated Gate Bipolar Transistor)).

  Inverter 200 converts, for example, a direct current from battery 300 into a current for driving motor generators MG1 and MG2 in response to a command signal from ECU 100, while being generated by first motor generator MG1 by the power of engine 1 The alternating current and the alternating current generated by the second motor generator MG2 by the regenerative brake are converted into a direct current for charging the battery 300. Inverter 200 supplies the alternating current generated by first motor generator MG1 as drive power for second motor generator MG2 in accordance with the traveling state.

  Here, by turning off all the semiconductor switching elements of the IPM for the first motor generator MG1 of the inverter 200 (shutdown control), the first motor generator MG1 is electrically disconnected from the electric system including the battery 300. (The first motor generator MG1 is idled). Also, by turning off all the semiconductor switching elements of the IPM for the second motor generator MG2 of the inverter 200 (shutdown control), the first motor generator MG2 is electrically disconnected from the electric system including the battery 300. (The second motor generator MG2 is idled).

  Then, ECU 100 executes cruise control. In the cruise control executed in this example, when the cruise control switch 107 is turned ON, the vehicle speed at the time of operation is acquired (stored) from the output signal of the wheel speed sensor 105, and the vehicle speed acquired at the time of this switch operation is set as the target. Control throttle opening / closing control (control that repeats opening / closing of throttle valve 13) so that the vehicle speed is set so that the current vehicle speed obtained from the output signal of wheel speed sensor 105 becomes the target vehicle speed (within the allowable vehicle speed range). It is control which manages vehicle speed by performing.

  Such cruise control is canceled when the cruise control switch 107 is turned off by the driver or when the driver depresses the accelerator pedal or the brake pedal. The target vehicle speed for cruise control may be a vehicle speed that can be freely set by the driver by operating a cruise vehicle speed setting switch or the like.

-Control during cruise control-
Next, an example of control during cruise control (ON) will be described below.

  First, in hybrid vehicles, as described above, during cruise control in the D range, the vehicle speed is managed within the allowable vehicle speed range by repeatedly opening and closing the control throttle while monitoring the vehicle speed. When the control throttle is in the “closed” state, regenerative torque (regenerative torque according to the battery state (SOC, Win, etc.)) is generated according to the vehicle speed or acceleration. Such regenerative control is performed. And the fall of a vehicle speed becomes quick compared with the coasting driving | running | working state in N range (neutral range). In such a situation, as shown in FIG. 6B, the time when the vehicle speed reaches the lower limit value of the allowable vehicle speed range during cruise control becomes earlier, and the time when the control throttle (throttle valve) is opened (time when energy consumption is resumed) ) Will be faster, and fuel consumption will deteriorate.

  In order to eliminate these points, this example focuses on the fact that the driver wants continuous constant speed driving during cruise control and does not need to generate braking force. It is characterized by reducing the consumption of energy by actively creating a coasting traveling state within the range and improving fuel efficiency by suppressing the amount of energy passing through the electric path.

  An example of the specific control (control during cruise control) will be described with reference to the flowchart of FIG. The control routine of FIG. 4 is repeatedly executed in the ECU 100 at predetermined time intervals. Note that the control routine of FIG. 4 shows only the control when the control throttle is in the “closed” state during cruise control.

  First, before the specific description of the control, the allowable acceleration range and the allowable vehicle speed range during cruise control will be described.

[Allowable acceleration range]
As shown in FIG. 5A, the allowable acceleration range at the time of cruise control is a lower limit (negative value) in which the acceleration of the hybrid vehicle HV (hereinafter sometimes simply referred to as “vehicle”) is smaller than “0” by a predetermined amount. Value) M to an upper limit value (positive value) N where the acceleration is larger than “0” by a predetermined amount. The lower limit value M and the upper limit value N of the allowable acceleration range are values that allow the driver to feel uncomfortable even when acceleration / deceleration occurs during cruise control driving (allowable acceleration / deceleration values). The value is empirically adapted by simulation or the like, and is stored in the ROM of the ECU 100, for example.

  In the example shown in FIG. 5A, the absolute value of the upper limit value N and the lower limit value M of the allowable acceleration range is the same value, but the present invention is not limited to this, and the absolute value of the upper limit value N and the lower limit value M It may be a value different from the absolute value. Further, the upper limit value N and the lower limit value M of the allowable acceleration range may be fixed values (constant values), or may be set variably according to the target vehicle speed.

[Allowable vehicle speed range]
As shown in FIG. 5B, the allowable vehicle speed range during cruise control is a lower limit value m (m = target vehicle speed−Δm) that is smaller than the target vehicle speed by a predetermined amount (Δm) with the target vehicle speed as a center. To an upper limit value n (n = target vehicle speed + Δn) that is larger than the target vehicle speed by a predetermined amount (Δn). The Δm and Δn of the allowable vehicle speed range are empirically determined in advance through experiments, simulations, and the like based on an allowable value of the current vehicle speed deviation (deviation) with respect to the target vehicle speed during cruise control driving (a vehicle speed deviation amount that the driver or the like does not care about). And the values (Δm, Δn) adapted based on the result, for example, are stored in the ROM of the ECU 100.

  In the example shown in FIG. 5B, Δm and Δn in the allowable vehicle speed range are set to the same value, but not limited thereto, and Δm and Δn may be set to different values. Δm and Δn may be fixed values (constant values), or may be set variably according to the target vehicle speed.

  Next, the control routine of FIG. 4 will be described for each processing block. During execution of the control routine of FIG. 4, the ECU 100 sequentially calculates the vehicle speed V and the acceleration α based on the output signal of the wheel speed sensor 105.

  The control routine shown in FIG. 4 is executed at the time of cruise control (the cruise control switch 107 (see FIG. 3) is ON) and the control throttle is in the “closed” state. As a method for determining whether or not the control throttle is “closed”, for example, a throttle opening obtained from an output signal of the throttle opening sensor 103 (a fully closed opening corresponding to a fully closed state in terms of control), or an ECU 100 that uses a throttle motor 14 may be determined based on a command signal (a fully closed signal corresponding to a fully closed state in terms of control) applied to the control signal 14.

  When the control routine of FIG. 4 is started, first, in step ST101, it is determined whether or not the vehicle acceleration α is equal to or less than the upper limit value N (α ≦ N) of the allowable acceleration range shown in FIG. If the determination result is negative (NO) (α> N), the process proceeds to step ST112.

  In step ST112, the regenerative torque is added to the output torque of the vehicle and the vehicle is decelerated by the regenerative control of the second motor generator MG2. The processing in these steps ST101 and ST112 is processing assuming that, for example, the hybrid vehicle HV is traveling on a downhill or the like. When the acceleration α of the vehicle increases (α> N), the regenerative braking is performed. This is a process for preventing the driver from feeling uncomfortable by decelerating immediately.

  If the determination result in step ST101 is affirmative (YES), the process proceeds to step ST102. In step ST102, it is determined whether or not the vehicle acceleration α is equal to or greater than the lower limit value M (M ≦ α) of the allowable acceleration range shown in FIG. 5A, and the determination result is affirmative (YES). If M ≦ α, the process proceeds to step ST103.

  In step ST103, it is determined whether or not the vehicle speed V is not less than the lower limit value m and not more than the upper limit value n (m ≦ V ≦ n) of the allowable vehicle speed range shown in FIG. If the determination result in step ST103 is affirmative (YES), that is, the vehicle acceleration α is within the allowable acceleration range (M ≦ α ≦ N), and the vehicle speed V is within the allowable vehicle speed range (m ≦ V If ≦ n), the process proceeds to step ST104.

  In step ST104, shutdown control is executed. Specifically, all the semiconductor switches of the IPM for the first motor generator MG1 of the inverter 200 and all the semiconductor switching elements of the IPM for the second motor generator MG2 are turned OFF, and the first motor generator MG1 and the first motor generator MG1 2 Motor generator MG2 is electrically disconnected from the electrical system (to be in a neutral state). By performing such shutdown control, it is possible to create a coasting traveling state within the constant speed traveling management range during cruise control (see FIG. 6A). Note that the shutdown control ends when the control throttle is in the “open” state.

  If the determination result in step ST102 is negative (NO) (when α <M), whether or not the vehicle speed V is smaller than the lower limit value m of the allowable vehicle speed range (V <m) in step ST121. Determine. If the determination result in step ST121 is negative (NO), that is, even if the vehicle acceleration α is smaller than the lower limit value M of the allowable acceleration range (deceleration state), the vehicle speed V is within the allowable vehicle speed range. When the value is equal to or greater than lower limit value m, shutdown control for electrically disconnecting motor generators MG1, MG2 from the electric system is executed (step ST104). However, this control continues until the vehicle speed V decelerates to the lower limit value m of the allowable vehicle speed range, and when the vehicle speed V becomes lower than the lower limit value m (when step ST121 becomes an affirmative determination (YES)). End with. Thereafter, assist control of the second motor generator MG2 is performed to generate a power running torque, and the vehicle speed V is controlled to fall within the allowable vehicle speed range of FIG. By such processes of steps ST121 and ST104, the opportunity of the coasting traveling state can be increased.

  If the determination result in step ST103 is negative (NO) (V <m or n <V), the vehicle speed V is greater than the upper limit value n of the allowable vehicle speed range in step ST111 (n It is determined whether or not <V). If the determination result in step ST111 is affirmative (YES) (when n <V), it is necessary to reduce the vehicle speed. Therefore, in step ST112, the vehicle output is controlled by the regenerative control of the second motor generator MG2. By gradually applying the regenerative torque to the torque, the vehicle speed is controlled so as to fall within the allowable vehicle speed range during cruise control shown in FIG. On the other hand, when the determination result of step ST111 is negative (NO) (when V <m), in step ST122, assist control of second motor generator MG2 is performed to generate power running torque.

  It should be noted that during the execution of the control routine of FIG. 4, when the accelerator pedal is operated (recognized based on the output signal of the accelerator opening sensor 102) or when the brake pedal is operated (the output signal of the brake pedal sensor 106). 4), the control routine and cruise control in FIG. 4 are stopped and the normal control mode is entered.

  As described above, according to the control of this example, the motor generators MG1 and MG2 are in a situation where the vehicle speed is within the constant speed travel management range during cruise control (when the control throttle is “closed”) and deceleration is not necessary. As shown in FIG. 6 (a), the conventional control (FIG. 6 (b)) reduces the vehicle speed when the control throttle is "closed". Compared to the regenerative control shown in Fig. 2). As a result, energy consumption (loss) can be reduced, and fuel consumption can be improved during cruise control.

-Other embodiments-
In the above example, an example in which the present invention is applied to control of an FF (front engine / front drive) type vehicle has been shown. However, the present invention is not limited to this, and an FR (front engine / rear drive) type vehicle or It can also be applied to control of a four-wheel drive vehicle.

  In addition, the trans-askicle of the hybrid vehicle is not limited to the form shown in FIG. 1, and for example, any other form such as a trans-askule to which a speed change function for performing a speed change by engagement / release of a friction engagement element is added. The present invention can also be applied to a hybrid vehicle on which this transaxle is mounted.

  In the above example, the example in which the present invention is applied to the control of the hybrid vehicle on which the two electric motors of the first motor generator and the second first motor generator are mounted is shown. However, one electric motor or three or more electric motors are used. It can also be applied to the control of an onboard hybrid vehicle.

  In the above example, the example in which the present invention is applied to the control of a hybrid vehicle in which an engine (internal combustion engine) and an electric motor (motor generator) are mounted as drive sources is shown, but the present invention is not limited to this, The present invention can also be applied to control of an electric vehicle (EV) in which only an electric motor (motor generator) is mounted as a drive source. Also in this case, when the vehicle speed is within the constant speed travel management range during cruise control and there is no need for deceleration, the motor may be electrically cut off to create a coasting travel state.

  In the above example, as means for making the output torque of the motor substantially zero, means for electrically shutting off the motor from the electric system (shutdown control) is adopted, but the present invention is limited to this. Instead, the output torque of the electric motor may be made substantially zero by other means, and the electric motor may be operated (see, for example, Japanese Patent No. 3421525).

  INDUSTRIAL APPLICABILITY The present invention can be used in a control device for a vehicle such as a hybrid vehicle or an electric vehicle equipped with an electric motor that outputs driving power, and more specifically, cruise control for controlling the vehicle speed to a target vehicle speed can be executed. It can be used for a vehicle control device.

1 Engine 13 Throttle valve 14 Throttle motor 21 Input shaft 3 Power split mechanism 4 Reduction mechanism 100 ECU
DESCRIPTION OF SYMBOLS 101 Engine speed sensor 102 Accelerator opening sensor 103 Throttle opening sensor 104 Shift position sensor 105 Wheel speed sensor 106 Brake pedal sensor 107 Cruise control switch 200 Inverter 300 Battery

Claims (6)

A vehicle control device that is applied to a vehicle equipped with an electric motor capable of outputting driving power, and that can execute cruise control for controlling the vehicle speed to a target vehicle speed,
A vehicle control apparatus, wherein the motor is operated with the output torque of the electric motor set to substantially zero on condition that the vehicle speed is within a constant speed traveling management range during cruise control. The vehicle control device according to claim 1,
A vehicle control apparatus, wherein the motor is operated with the output torque of the electric motor set to substantially zero on condition that the vehicle speed is within a predetermined allowable vehicle speed range during cruise control. The vehicle control device according to claim 1,
An apparatus for controlling a vehicle, wherein the motor is operated with the output torque of the electric motor set to substantially zero on condition that the acceleration of the vehicle is within a predetermined allowable acceleration range during cruise control. The vehicle control device according to claim 1,
At the time of cruise control, the motor is operated with the output torque of the motor being substantially zero on condition that the vehicle speed is within a predetermined allowable vehicle speed range and the vehicle acceleration is within the predetermined allowable acceleration range. A control apparatus for a vehicle. In the control apparatus of the vehicle as described in any one of Claims 1-4,
A vehicle control apparatus characterized in that the output torque of the motor is made substantially zero by electrically disconnecting the motor from an electric system. The vehicle control device according to claim 5, wherein
A control apparatus for a vehicle, wherein the electric motor is electrically disconnected from an electric system by turning off each switching element of an inverter provided for the electric motor.

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