JP2022088027A - Vehicle controller - Google Patents

Abstract

To suppress change of a vehicle speed different from that at the time of inertia traveling of a vehicle while rotating a dynamo at the highest efficiency rotation speed by controlling an engine rotation speed, during the inertia traveling of the vehicle.SOLUTION: A vehicle 1 comprises an internal combustion engine 10, a dynamo 60 driven by the rotational output of this internal combustion engine 10, a transmission 30 that transmits the rotational output of the internal combustion engine 10 to drive wheels 40, and a battery 50 charged by the dynamo 60. During inertia traveling of the vehicle, when a charge state of the battery 50 is less than a predetermined value, a vehicle controller controls an engine rotation speed so that the power generation efficiency of the dynamo 60 is maximized while making a forward clutch 31 of the transmission 30 in a semi-engaged state.SELECTED DRAWING: Figure 1

Description

The present invention relates to a vehicle control device that controls a vehicle.

It is known that when fuel injection is performed during coasting of a vehicle driven by the rotational output of an internal combustion engine and the state of charge of the vehicle-mounted battery is less than a predetermined value, the vehicle-mounted battery is charged by a generator. (See, for example, Patent Document 1).

Japanese Patent Application Laid-Open No. 2003-2494998

By the way, it is preferable to rotate the generator at the rotation speed at which the power generation efficiency is maximized (maximum efficiency rotation speed) from the viewpoint of improving fuel efficiency. However, if the rotation speed of the internal combustion engine is controlled during coasting of the vehicle in order to rotate the generator at the highest efficiency rotation speed, the vehicle speed changes differently from those during coasting of the vehicle, which gives the driver a sense of discomfort. There is a risk.

Therefore, in view of the above problems, the present invention suppresses a change in vehicle speed different from that during coasting of the vehicle while rotating the generator at the maximum efficiency rotation speed by controlling the engine rotation speed during coasting of the vehicle. It is an object of the present invention to provide a vehicle control device.

Therefore, in the vehicle control device according to the present invention, the vehicle is charged by an internal combustion engine, a generator driven by the rotational output of the internal combustion engine, a transmission that transmits the rotational output of the internal combustion engine to the drive wheels, and a generator. When a predetermined condition including that the charged state of the battery becomes less than a predetermined value is satisfied during coasting of a vehicle equipped with an internal combustion engine, the generator is set while the forward clutch of the transmission is half-engaged. The engine rotation speed is controlled so that the power generation efficiency of the engine is maximized.

According to the vehicle control device of the present invention, it is possible to suppress a change in vehicle speed different from that during coasting of the vehicle while rotating the generator at the maximum efficiency rotation speed by controlling the engine rotation speed during coasting of the vehicle. ..

It is a schematic diagram which shows an example of the drive system of a vehicle. It is a flowchart which shows an example of the main routine about the vehicle control for power generation. It is a flowchart which shows an example of the vehicle control permission determination routine for power generation. It is a flowchart which shows an example of the vehicle control routine for power generation. It is explanatory drawing which shows the temperature characteristic of a generator. It is a flowchart which shows an example of the vehicle control release routine for power generation. It is a time chart which shows an example of the internal operation of a vehicle when there is a fuel cut. It is a time chart which shows an example of the internal operation of a vehicle when there is no fuel cut.

Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 shows an example of a vehicle drive system to which a vehicle control device is applied. The drive source of the vehicle 1 is an internal combustion engine 10. The internal combustion engine 10 is, for example, a four-cycle engine, and is an intake valve 11 that opens and closes an intake port, an exhaust valve 12 that opens and closes an exhaust port, a fuel injection device 13 that injects fuel, an ignition device 14 that discharges sparks, and an intake air amount. An electronically controlled throttle valve 15 for adjusting the fuel pressure is provided.

An air-fuel mixture in which the intake air that has passed through the throttle valve 15 and the fuel injected from the fuel injection device 13 are mixed is formed in the combustion chamber, and this air-fuel mixture is a piston with both the intake valve 11 and the exhaust valve 12 closed. As 16 rises, it is compressed. Then, the compressed air-fuel mixture is ignited by the spark discharge of the ignition device 14, and the piston 16 is lowered by the combustion pressure of the air-fuel mixture, so that the piston 16 and the crank shaft 18 connected via the connecting rod 17 rotate. Is caused. The rotational motion taken out from the crank shaft 18 is transmitted to the drive wheels 40 via the torque converter 20 and the transmission 30 as the driving force of the vehicle 1.

The transmission 30 has a forward clutch 31 and a CVT (Continuously Variable Transmission) 32. The forward clutch 31 is connected to the torque converter 20 via a transmission input shaft 33 or the like, and the CVT 32 is connected to the forward clutch 31 via an intermediate shaft 34 or a planetary gear mechanism (not shown) and shifts to the drive wheel 40. It is connected via the machine output shaft 35 and the like.

The forward clutch 31 is engaged when the vehicle 1 is advanced, and is connected to the drive plate 31A on the drive side connected to the transmission input shaft 33, and the driven plate 31B on the driven side connected to the CVT 32 via the intermediate shaft 34 and the like. And have. The drive plate 31A and the driven plate 31B are friction engaging elements, and the drive plate 31A and the driven plate 31B engage with each other when the forward clutch 31 is engaged. Fastening and releasing of the drive plate 31A and the driven plate 31B is performed by hydraulic control of hydraulic oil supplied to a clutch driving actuator (not shown) such as a piston.

The CVT 32 is a continuously variable transmission including a primary pulley 32A and a secondary pulley 32B in which a pair of movable cones are arranged so as to face each other in the radial direction, and a belt 32C wound between the pulleys 32A and 32B. It is a mechanism. The rotation of the primary pulley 32A is transmitted to the secondary pulley 32B via the belt 32C, and the rotation of the secondary pulley 32B is transmitted to the drive wheels 40 via the transmission output shaft 35 and the like. When each pair of movable cones of the primary pulley 32A and the secondary pulley 32B is moved in the axial direction by hydraulic control of the hydraulic oil supplied to the pair of movable cones, the positions where the primary pulley 32A and the secondary pulley 32B and the belt 32C come into contact with each other. Radius changes. As a result, the pulley ratio (rotation ratio) between the primary pulley 32A and the secondary pulley 32B changes, and the gear ratio is adjusted steplessly.

A generator (alternator) 60 that supplies DC power to an in-vehicle electrical component (not shown) and charges an in-vehicle battery 50 by generating power in the internal combustion engine 10 by using a rotational motion generated in a crank shaft 18 as a driving force. Is installed. The generator 60 includes an AC generator using an electric magnet in the field and a rectifier circuit for rectifying the AC output thereof, and the generated voltage changes according to the field current.

The internal combustion engine 10 is controlled by an internal combustion engine control unit (hereinafter referred to as "ECU") 100, the generator 60 is controlled by a generator control unit (hereinafter referred to as "ACU") 200, and the transmission 30 is a transmission control unit. It is controlled by 300 (hereinafter referred to as "TCU"). The ECU 100, ACU 200, and TCU 300 each have a built-in microcomputer, and mutual communication is performed via a communication network 400 such as CAN (Controller Area Network).

The ECU 100 inputs the output signals of the accelerator sensor, the accelerator switch 71, the crank shaft sensor 72, and the throttle opening sensor 73 (not shown). The accelerator sensor outputs a signal that changes according to the amount of depression of the accelerator pedal 81. The accelerator switch 71 outputs a signal that changes depending on whether or not the accelerator pedal 81 is depressed. The crank shaft sensor 72 outputs a signal that changes according to the speed of rotational movement (hereinafter referred to as “engine rotation speed”) taken out from the crank shaft 18. The throttle opening sensor 73 outputs a signal that changes according to the opening of the throttle valve 15. Based on the output signals of the above sensors and switches, the ECU 100 indicates the amount of depression of the accelerator pedal 81, the measured values of the engine rotation speed and the opening degree of the throttle valve 15, and information indicating whether or not the accelerator pedal 81 is depressed. To get. Then, the ECU 100 controls the fuel injection device 13, the ignition device 14, and the throttle valve 15 based on the above measured values and information.

The ECU 100 sets the target opening degree of the throttle valve 15 based on the measured value of the depression amount of the accelerator pedal 81, and drives the motor of the throttle valve 15 so that the measured value of the opening degree of the throttle valve 15 becomes the target opening degree. Control. The ECU 100 calculates the fuel injection amount based on the intake air amount and the stoichiometric air-fuel ratio, and determines an appropriate ignition timing according to the measured value N of the engine rotation speed. The intake air amount can be obtained by various methods. For example, it is actually measured by an intake amount sensor or estimated from the measured value of the opening degree of the throttle valve 15 and the measured value N of the engine rotation speed. You can get it. Then, the ECU 100 outputs an injection pulse signal reflecting the calculated fuel injection amount to the fuel injection device 13, and outputs an ignition signal reflecting the determined ignition timing to the ignition device 14.

Further, the ECU 100 changes from a state in which the accelerator pedal 81 is depressed (hereinafter referred to as “accelerator on”) to a state in which the accelerator pedal 81 is not depressed (hereinafter referred to as “accelerator off”) based on the output signal of the accelerator switch 71. Monitor whether the vehicle 1 is coasting. When the ECU 100 determines that the vehicle 1 is coasting, the ECU 100 sets the fuel cut permission flag to the ON state when the start condition such that the engine rotation speed becomes a predetermined value or more is satisfied. Fuel cut control is performed to stop the fuel injection of the fuel injection device 13 in order to improve fuel efficiency. Then, when the release condition such that the engine rotation speed becomes less than a predetermined value is satisfied, the fuel cut control is terminated and the fuel injection is restarted.

The ACU 200 has a field of the generator 60 so that the generated voltage of the generator 60 becomes a predetermined voltage suitable as a power supply voltage of an in-vehicle electrical component even if the engine rotation speed changes according to the operating state of the vehicle 1. Control the current. When the ECU 100 performs fuel cut control, the ACU 200 increases the field current in response to a command signal from the ECU 100 to raise the generated voltage of the generator 60 more than usual to improve fuel efficiency. You may.

Further, the ACU 200 estimates the charge state (SOC) of the vehicle-mounted battery 50 in order to confirm whether or not the vehicle-mounted battery 50 needs to be charged by the generator 60. For example, the ACU 200 inputs an output signal of a current sensor 74 that outputs a signal that changes according to the charge / discharge current of the vehicle-mounted battery 50, obtains a measured value of the charge / discharge current based on the output signal, and integrates the measured values. The SOC of the vehicle-mounted battery 50 is estimated based on the integrated value. Further, the ACU 200 inputs an output signal of the battery temperature sensor 75 that outputs a signal that changes according to the temperature (battery temperature) in the vehicle-mounted battery 50, and acquires a measured value T of the battery temperature based on this output signal. ..

The TCU 300 controls the engagement and release of the forward clutch 31 via a clutch drive actuator (not shown) according to the operation input signal of the driver and the operating state of the vehicle 1 received from the ECU 100, and controls the gear ratio of the CVT 32. Control. Further, the TCU 300 inputs an output signal of the oil temperature sensor 76 that outputs a signal that changes according to the oil temperature in the transmission 30 for diagnosing the oil temperature in the transmission 30 and the like, and inputs the output signal in the transmission 30. Obtain the measured value of the oil temperature of.

By the way, when the idle control is performed so that the engine rotation speed approaches the idle rotation speed Ni when the fuel injection is restarted while the vehicle 1 is coasting, the engine rotation speed rotates the generator 60 at the maximum efficiency rotation speed Nmax. It is assumed that the speed will be lower than the speed required to make it (hereinafter referred to as "target engine rotation speed") Nt. Here, the maximum efficiency rotation speed Nmax is the speed at which the power generation efficiency of the generator 60 becomes the highest when the generator 60 generates power so as to generate a predetermined power generation voltage. In contrast to the above assumption, from the viewpoint of improving fuel efficiency, it is conceivable to perform control to increase and maintain the engine rotation speed to the target engine rotation speed Nt in order to rotate the generator 60 at the maximum efficiency rotation speed Nmax. However, if control is performed to increase and maintain the engine rotation speed while the vehicle 1 is coasting, a vehicle speed change different from that when the vehicle is coasting may occur, which may give the driver a sense of discomfort. Therefore, the ECU 100 cooperates with the ACU 200 and the TCU 300 under predetermined conditions to set the generator 60 in a semi-engaged state while the forward clutch 31 is half-engaged after the restart of fuel injection and before the start of idle control during coasting of the vehicle 1. The vehicle for power generation is controlled to rotate at the maximum efficiency rotation speed Nmax. Here, the semi-engaged state of the forward clutch 31 is a state in which the drive plate 31A and the driven plate 31B are continuously or intermittently engaged (contacted) and rotated at different speeds. The ECU 100, ACU 200, and TCU 300 configure a vehicle control device that controls a vehicle for power generation and related processes (hereinafter, referred to as "process related to control of a vehicle for power generation").

The ECU 100 performs processing related to vehicle power generation control by software processing in which the processor reads a program stored in the non-volatile memory into the volatile memory and executes the program in the built-in microcomputer. However, it does not exclude that part or all of the processing related to power generation vehicle control is realized by the hardware configuration.

The ECU 100 inputs output signals of the vehicle speed sensor 77 and the brake switch 78 in addition to the accelerator switch 71, the crank shaft sensor 72, and the throttle opening sensor 73 in order to perform processing related to vehicle control for power generation. The vehicle speed sensor 77 outputs a signal that changes according to the vehicle speed, and the brake switch 78 outputs a signal that changes depending on whether or not the brake pedal 82 is depressed. The ECU 100 acquires the measured value V of the vehicle speed based on the output signal of the vehicle speed sensor 77, and acquires the information indicating whether or not the brake pedal 82 is depressed based on the output signal of the brake switch 78. Then, the ECU 100 performs processing related to power generation vehicle control based on each measured value of the engine rotation speed, the opening degree of the throttle valve 15, and the vehicle speed, and each information indicating whether or not the accelerator pedal 81 and the brake pedal 82 are depressed. conduct.

Further, the TCU 300 controls the forward clutch 31 to be in the half-engaged state (hereinafter, referred to as "half-engagement control") by receiving the command signal from the ECU 100. The TCU 300 inputs the output signals of the two sensors, the first rotation speed sensor 79A and the second rotation speed sensor 79B, in order to perform the semi-fastening control. The first rotation speed sensor 79A outputs a signal that changes according to the rotation speed of the drive plate 31A (hereinafter, referred to as “first rotation speed”). The second rotation speed sensor 79B outputs a signal that changes according to the rotation speed of the driven plate 31B (hereinafter, referred to as “second rotation speed”). The TCU 300 acquires the measured value N1 of the first rotation speed based on the output signal of the first rotation speed sensor 79A, and acquires the measured value N2 of the second rotation speed based on the output signal of the second rotation speed sensor 79B. .. Then, the TCU 300 performs semi-fastening control based on the measured value N1 of the first rotation speed and the measured value N2 of the second rotation speed.

FIG. 2 shows an example of a main routine of processing related to power generation vehicle control that is repeatedly executed in the ECU 100 when the power supply to the ECU 100 is started. The process related to power generation vehicle control will be described as being executed in parallel with other control processes in the ECU 100, but it is not excluded that the process is executed as a part of other control processes. Further, when starting the process related to the power generation vehicle control, it is assumed that the power generation vehicle control permission flag and the power generation vehicle control execution flag, which will be described later, are initialized and turned off.

In step 101 (hereinafter, the step is abbreviated as “S”), the ECU 100 determines whether or not to permit power generation vehicle control. When the ECU 100 determines in S101 that the power generation vehicle control is permitted, the power generation vehicle control permission flag is set to the ON state, and when it is determined that the power generation vehicle control is prohibited, the power generation vehicle control permission flag is set. Set to off state. The details of the determination as to whether or not to permit the control of the vehicle for power generation will be described later.

In S102, the ECU 100 advances the process to S103 if the power generation vehicle control is permitted (YES), while the processing proceeds to S104 if the power generation vehicle control is not permitted (NO). The ECU 100 can determine whether or not the power generation vehicle control is permitted based on the power generation vehicle control permission flag.

In S103, the ECU 100 controls the vehicle for power generation. The ECU 100 sets the power generation vehicle control execution flag indicating that the power generation vehicle control has been executed in S103 to the ON state, returns the process to S101, and confirms whether or not the power generation vehicle control is permitted. In short, the ECU 100 continuously controls the power generation vehicle as long as the power generation vehicle control is permitted. The details of vehicle control for power generation will be described later.

In S104, the ECU 100 advances the process to S105 when the power generation vehicle is being controlled (YES), while the power generation vehicle is not controlled (NO) when the power generation vehicle is not being controlled, and S105 is omitted. The process is temporarily terminated, and the execution is started again from S101. The ECU 100 can determine whether or not the power generation vehicle is being controlled based on the state of the power generation vehicle control execution flag.

In S105, the ECU 100 releases the power generation vehicle control executed in S103. The details of releasing the control of the vehicle for power generation will be described later.

FIG. 3 shows an example of a power generation vehicle control permission determination routine called in S101 of the process related to power generation vehicle control (see FIG. 2).

In S201, the ECU 100 determines whether or not the SOC of the vehicle-mounted battery 50 is less than the lower limit. This lower limit value is a value set based on the minimum charging state required for starting and running the vehicle 1. The ECU 100 can acquire the SOC of the vehicle-mounted battery 50 from the ACU 200 via the communication network 400. Then, when the ECU 100 determines that the SOC of the vehicle-mounted battery 50 is less than the lower limit (YES), the ECU 100 determines that it is necessary to control the vehicle for power generation in order to perform rapid battery charging, and performs processing. Proceed to S202. On the other hand, when the ECU 100 determines that the SOC of the in-vehicle battery 50 is equal to or higher than a predetermined value (NO), the ECU 100 determines that rapid battery charging is not necessary, and therefore there is no need for power generation vehicle control. The process proceeds to S208.

In S202, the ECU 100 determines whether or not the rotation speed sensors 79A and 79B used in the vehicle control for power generation are normal. Whether or not the first rotation speed sensor 79A is normal can be determined based on the comparison between the measured value N1 of the first rotation speed and the measured value N of the machine rotation speed. Whether or not the second rotation speed sensor 79B is normal can be determined based on the comparison between the measured value N2 of the second rotation speed and the measured value V of the vehicle speed. Then, when the ECU 100 determines that the rotational speed sensors 79A and 79B are normal (YES), it determines that the power generation vehicle control is possible, and proceeds to the process to S203. On the other hand, when the ECU 100 determines that the rotational speed sensors 79A and 79B are abnormal (NO), it determines that the power generation vehicle control is impossible, and proceeds to the process to S208.

In S203, the ECU 100 determines whether or not the accelerator is off based on the output signal of the accelerator switch 71. Then, when the ECU 100 determines that the accelerator is off (YES), it determines that the vehicle 1 may be coasting, and proceeds to the process to S204. On the other hand, when the ECU 100 determines that the accelerator is on (NO), the ECU 100 determines that the vehicle 1 is not coasting, and proceeds to the process to S208.

In S204, the ECU 100 determines that the engine rotation speed can be controlled as the vehicle control for power generation because fuel injection is possible when the fuel cut permission flag is off (YES). , The process proceeds to S205. On the other hand, when the fuel cut permission flag is on (NO), the ECU 100 determines that the engine rotation speed cannot be controlled as the vehicle control for power generation because the fuel injection is prohibited. Then, the process proceeds to S208.

In S205, the ECU 100 determines whether or not the vehicle 1 is traveling based on the output signal of the vehicle speed sensor 77. Whether or not the vehicle 1 is running can be determined by determining whether or not the measured value V of the vehicle speed obtained based on the output signal of the vehicle speed sensor 77 is higher than 0 km / h or a value in the vicinity thereof. Is. Then, when the ECU 100 determines that the vehicle 1 is running (YES), the ECU 100 determines that the kinetic energy of the vehicle 1 can be used for power generation by the generator 60 because the vehicle 1 is coasting. Then, the process proceeds to S206. On the other hand, when the ECU 100 determines that the vehicle 1 is not running, that is, the vehicle is stopped (NO), the ECU 100 determines that the kinetic energy of the vehicle 1 used for power generation by the generator 60 is not generated. , The process proceeds to S208.

In S206, the ECU 100 determines whether or not the measured value of the oil temperature in the transmission 30 is less than the threshold value based on the output signal of the oil temperature sensor 76. This threshold value is the lower limit temperature of the oil temperature at which the drive plate 31A and the driven plate 31B slide with each other and the half-engaged state of the forward clutch 31 becomes impossible. Then, when the ECU 100 determines that the measured value of the oil temperature in the transmission 30 is less than the threshold value (YES), the ECU 100 determines that the forward clutch 31 can be half-engaged, and processes the process to S207. Proceed. On the other hand, when the ECU 100 determines that the measured value of the oil temperature in the transmission 30 is equal to or higher than the threshold value (NO), the ECU 100 determines that the half-engaged state of the forward clutch 31 is impossible, and performs the process S208. Proceed to.

In S207, the ECU 100 permits power generation vehicle control, while in S208, the ECU 100 prohibits power generation vehicle control. Then, after executing S207 or S208, the ECU 100 exits the power generation vehicle control permission determination routine and proceeds to the main routine S102 of the power generation vehicle control process (see FIG. 2).

FIG. 4 shows an example of a power generation vehicle control routine called in S103 of the process related to power generation vehicle control (see FIG. 2), which is the main routine.

In S301, the ECU 100 transmits a command signal to the TCU 300 to perform semi-fastening control. Upon receiving the command signal, the TCU 300 performs semi-engagement control by hydraulically controlling the hydraulic oil supplied to the clutch drive actuator (not shown) of the forward clutch (referred to as “F clutch” in the drawing; the same applies hereinafter) 31. The specific contents of the semi-fastening control will be described later.

In S302, the ECU 100 determines whether or not the forward clutch 31 is in the semi-engaged state. The ECU 100 executes S302 in response to the result of determining whether or not the TCU 300 is in the semi-fastened state based on the two measured values N1 and N2 of the first rotation speed and the second rotation speed. S302 may be executed based on the two measured values N1 and N2 of the first rotation speed and the second rotation speed received from the TCU 300.

By the way, when the vehicle 1 is coasting with the fuel injection stopped, at least the first rotation speed and the second rotation speed are substantially the same in the engaged state of the forward clutch 31. However, when the forward clutch 31 shifts from the engaged state to the half-engaged state, a speed difference occurs between the first rotation speed and the second rotation speed, and when the forward clutch 31 further shifts to the released state, the speed difference becomes larger than in the half-engaged state. growing. Therefore, whether or not the forward clutch 31 is in the semi-engaged state can be determined based on the difference between the two measured values N1 and N2 of the first rotation speed and the second rotation speed. The ECU 100 or the TCU 300 may execute S302 after a predetermined time has elapsed from S21 in consideration of the operating time of the forward clutch 31 and the rotational inertia of the crank shaft 18. Further, the ECU 100 or the TCU 300 may temporarily increase the engine rotation speed. This is because if the forward clutch 31 is in the released state, the second rotation speed does not increase even if the engine rotation speed increases, so it is clearly determined whether the forward clutch 31 is in the semi-engaged state or the released state. Because it can be done.

If the ECU 100 determines in S302 that the forward clutch 31 is in the semi-engaged state (YES), the ECU 100 advances the process to S303. On the other hand, if the ECU 100 determines that the forward clutch 31 is not in the semi-engaged state (NO), it determines that the power generation vehicle control cannot be performed, and processes related to the power generation vehicle control (see FIG. 2). ) And finish this.

In S303, the ECU 100 determines whether or not the measured value T of the battery temperature is less than a predetermined threshold value Tth. The ECU 100 acquires the measured value T of the battery temperature acquired by the ACU 200 based on the output signal of the battery temperature sensor 75 by receiving it as communication information via the communication network 400. Then, when the ECU 100 determines that the measured value T of the battery temperature is less than the threshold value Tth (YES), the process proceeds to S304. On the other hand, if the ECU 100 determines that the measured value T of the battery temperature is equal to or higher than the threshold value Tth (NO), the process proceeds to S305.

In S304, the ECU 100 sets the target engine rotation speed Nt at the speed _NA when the measured value T of the battery temperature is less than the threshold value Tth. On the other hand, in S305, the ECU 100 sets the target engine rotation speed Nt when the measured value T of the battery temperature is equal to or higher than the threshold value Tth to a speed _NB higher than the speed _NA .

Here, with reference to FIG. 5, the reason why the target engine rotation speed Nt is changed according to the battery temperature will be described. FIG. 5 shows the relationship between the rotation speed of the generator 60 and the amount of power generation during cold and warm. In FIG. 5, comparing the rotation speeds required to generate the same amount of power generation Q [A] between the generator 60 at the time of cooling and the generator 60 at the time of warming up, the rotation speed of the generator 60 at the time of warming up is compared. _NH is higher than the rotation speed _NL of the generator 60 at the time of cooling. Therefore, as the ambient temperature of the generator 60 increases, the maximum efficient rotation speed Nmax of the generator 60 also increases. The ambient temperature of the generator 60 can be indirectly grasped by the battery temperature, and the engine rotation speed required when rotating the generator 60 at the maximum efficiency rotation speed Nmax as described above is the target engine rotation speed Nt. be. Therefore, the target engine rotation speed Nt is changed according to the battery temperature.

Although the battery temperature is used as the ambient temperature of the generator 60, it is natural that a temperature parameter that indirectly indicates the temperature of the generator 60 itself or the ambient temperature of the generator 60 may be used.

In S306, the ECU 100 performs feedback control so that the measured value N of the engine rotation speed acquired based on the output signal of the crank shaft sensor 72 becomes the target engine rotation speed Nt set in S304 or S305.

For example, in S306, the ECU 100 calculates the operation amount of the drive motor (not shown) of the throttle valve 15 based on the deviation between the target engine rotation speed Nt and the measured value N of the engine rotation speed, and reflects this operation amount. The control signal is output to the drive motor. Feedback control such as PI control and PID control can be used to calculate the operation amount of the drive motor of the throttle valve 15.

In S306, when the measured value N of the engine rotation speed is higher than the target engine rotation speed Nt, the deviation becomes a negative value, so that the operation amount of the drive motor calculated by PI control or PID control is It is a relatively small value. Therefore, since the throttle valve 15 is in a fully closed state or has a relatively small opening degree, the engine rotation speed decreases or its increase is suppressed. On the other hand, when the measured value N of the engine rotation speed drops below the target engine rotation speed Nt, the deviation becomes a positive value, so that the operation amount becomes a relatively large value and the opening degree of the throttle valve 15 increases. As a result, the measured value N of the engine rotation speed rises toward the target engine rotation speed Nt.

After executing S306, the ECU 100 exits the power generation vehicle control routine and proceeds to S101 of the process related to power generation vehicle control (see FIG. 2).

Here, a mode of semi-fastening control executed by the TCU 300 in response to a command signal from the ECU 100 by S301 will be described. The semi-fastening control is performed so that even if the engine rotation speed is controlled during the inertial running of the vehicle 1 in S306, the occurrence of a vehicle speed change different from that during the inertial running of the vehicle 1 is suppressed, and some embodiments are performed. Conceivable.

As the first aspect of the semi-fastening control, the TCU 300 controls the hydraulic pressure of the clutch drive actuator so that the engagement pressure between the drive plate 31A and the driven plate 31B becomes a predetermined pressure. The predetermined pressure is, for example, the minimum engagement pressure that can be generated by the clutch driving actuator. Specifically, the TCU 300 controls the hydraulic pressure of the clutch drive actuator so that the difference between the two measured values N1 and N2 of the first rotation speed and the second rotation speed becomes a predetermined value according to the above-mentioned predetermined pressure. ..

As a second aspect of the semi-engagement control, when the vehicle 1 is decelerating due to coasting, the TCU 300 determines the hydraulic pressure of the clutch drive actuator so that the measured value V of the vehicle speed decreases according to the predetermined deceleration a. Take control. The predetermined deceleration a is a deceleration that occurs when the vehicle 1 decelerates due to coasting, is determined in advance by an experiment, a simulation, or the like, and is stored in a ROM (Read Only Memory) of the ECU 100 or the like. For example, the TCU 300 is clutch-driven so that the measured value N2 of the second rotation speed becomes the ideal second rotation speed obtained by converting the current ideal vehicle speed obtained from the predetermined deceleration a by the set gear ratio of the CVT 32 or the like. It controls the hydraulic pressure of the actuator. The ECU 100 acquires the slope of the road surface from a gradient acquisition means (for example, an acceleration sensor) that measures or estimates the gradient of the road surface on which the vehicle 1 is traveling, and changes a predetermined deceleration a according to the gradient of the road surface. You may let me.

As a third aspect of the semi-engagement control, when the vehicle 1 is decelerating due to coasting, the TCU 300 increases the engagement pressure between the drive plate 31A and the driven plate 31B as the SOC of the vehicle-mounted battery 50 rises. The hydraulic pressure of the clutch drive actuator is controlled so as to decrease. The TCU 300 acquires the SOC value of the vehicle-mounted battery 50 from the ACU 200 via the communication network 400.

The first to third aspects of the semi-fastening control may be used in combination. For example, when the vehicle 1 is decelerating, in principle, the semi-fastening control is performed according to the second or third aspect, and when the measured value N of the engine rotation speed is increasing, the minimum according to the first aspect. Semi-fastening control may be performed by the engagement pressure of. Further, the mode of the semi-engagement control may be different before and after determining whether or not the forward clutch 31 is in the semi-engaged state in S302.

FIG. 6 shows an example of a power generation vehicle control release routine called in S105 of the process related to power generation vehicle control (see FIG. 2).

In S401, the ECU 100 determines whether or not the brake pedal 82 is in the depressed state (hereinafter referred to as “brake on”) based on the output signal of the brake switch 78. Then, when the ECU 100 determines that the brake is on (YES), the ECU 100 determines that there is no possibility of the acceleration operation, and proceeds to the process to S403. On the other hand, if the ECU 100 determines that the brake is not on, that is, the brake pedal 82 is not depressed (hereinafter referred to as "brake off") (NO), the process proceeds to S402.

In S402, the ECU 100 determines whether or not the accelerator is off based on the output signal of the accelerator switch 71. Then, when the ECU 100 determines that the accelerator is off (YES), it determines that the acceleration operation is not performed but there is a possibility of the acceleration operation, and proceeds to the process to S404. On the other hand, if the ECU 100 determines that the accelerator is on (NO), it determines that the acceleration operation has been performed, and proceeds to the process to S405.

The ECU 100 executes S403 when there is no possibility of acceleration operation, executes S404 when there is a possibility of acceleration operation although the acceleration operation is not performed, and S405 when the acceleration operation is performed. Is executed, and the engagement speed of the forward clutch 31 is set according to the possibility of acceleration operation. Assuming that the fastening speed set in S403 is UA, the fastening speed set in _S404 is _UB , and the fastening speed set in _S405 is _UC , the magnitude relationship between the fastening speeds _UA , _UB , and UC accelerates. As the possibility of operation increases, _UA < _UB < _UC in order to quickly engage the forward clutch 31.

In S406, the ECU 100 performs idle control to bring the measured value N of the engine rotation speed closer to the idle rotation speed Ni.

In S407, the ECU 100 determines whether or not the measured value N of the engine rotation speed has converged to the idle rotation speed Ni based on the output signal of the crank shaft sensor 72. Then, when the ECU 100 determines that the measured value N of the engine rotation speed has converged to the idle rotation speed Ni (YES), the process proceeds to S408, while the measured value N of the engine rotation speed is the idle rotation speed. If it is determined that the deviation from Ni is still present (NO), the process is returned to S401.

In S408, the ECU 100 transmits a command signal to the TCU 300 to control the forward clutch 31 to be engaged (engagement control). Upon receiving the command signal, the TCU 300 performs engagement control by hydraulically controlling the hydraulic oil supplied to the clutch drive actuator.

In S409, the ECU 100 determines whether or not the forward clutch 31 is in the engaged state. Whether or not it is in the fastened state can be determined by whether or not the two measured values N1 and N2 of the first rotation speed and the second rotation speed substantially match each other. Then, when the ECU 100 determines that the forward clutch 31 is in the engaged state (YES), the ECU 100 exits the power generation vehicle control release routine and ends the process related to the power generation vehicle control (see FIG. 2). On the other hand, if it is determined that the forward clutch 31 is not in the engaged state (NO), the ECU 100 returns the process to S408 and transmits a command signal to the TCU 300 to perform the engagement control again.

In the ECU 100, at least that the measured value N of the engine rotation speed converges to the idle rotation speed Ni and that the two measured values N1 and N2 of the first rotation speed and the second rotation speed substantially match each other. When one of the conditions is satisfied, the fastening control (S408) may be performed. Such control is particularly effective in that when the ECU 100 determines that the accelerator is on in S402, the delay in response to the acceleration operation may be suppressed by executing S406 and S407.

FIG. 7 shows an example of the internal operation of the vehicle 1 by the processing related to the fuel cut control and the subsequent power generation vehicle control.

When the vehicle 1 starts coasting by changing from accelerator on to accelerator off at time t1, the ECU 100 sets a fuel cut permission flag indicating that fuel injection is stopped when the start condition of fuel cut control is satisfied. Set to the on state and start fuel cut control. Even during the fuel cut control, the SOC of the vehicle-mounted battery 50 increases due to the power generation of the generator 60, but as shown in FIG. 7, the SOC of the vehicle-mounted battery 50 has not reached the lower limit.

At time t2, when the fuel cut control release condition is satisfied, the ECU 100 sets the fuel cut permission flag to the off state, and the fuel cut control ends. At this time, as shown in FIG. 7, the SOC of the vehicle-mounted battery 50 is less than the lower limit value, and the vehicle 1 is running. Therefore, if the oil temperature in the transmission 30 is less than the threshold value and the rotation speed sensors 79A and 79B are normal, the ECU 100 turns on the power generation vehicle control permission flag indicating the permission of the power generation vehicle control. Set. Then, the ECU 100 first causes the TCU 300 to perform the semi-engagement control of the forward clutch 31 as the vehicle control for power generation. Due to this semi-fastening control, a speed difference is generated between the first rotation speed (solid line) and the second rotation speed (broken line).

At time t3, when the ECU 100 determines that the forward clutch 31 is in the semi-engaged state, the current engine rotation speed is the target engine rotation speed Nt required to rotate the generator 60 at the maximum efficiency rotation speed Nmax. The control of the engine rotation speed is started so as to be.

When the SOC of the vehicle-mounted battery 50 becomes equal to or higher than the lower limit value at time t4, the ECU 100 changes the power generation vehicle control permission flag from the on state to the off state to prohibit power generation vehicle control. As a result, the ECU 100 ends the control for matching the engine rotation speed with the target engine rotation speed Nt, and starts the idle control.

At times t3 to t4, the engine rotation speed increases and is maintained up to the target engine rotation speed Nt, so that the SOC of the vehicle-mounted battery 50 increases at a larger rate of change than during fuel cut control (time t1 to t2).

Further, at times t3 to t4, although the first rotation speed increases by increasing and maintaining the engine rotation speed up to the target engine rotation speed Nt, the second rotation speed is increased because the semi-fastening control is performed. The rise is suppressed. Assuming that the semi-fastening control is not performed at times t3 to t4, the engine rotation speed increases and is maintained up to the target engine rotation speed Nt, so that the second rotation speed increases in the same manner as the first rotation speed. Since the second rotation speed is reflected in the vehicle speed and the engine rotation speed is reflected in the first rotation speed, the vehicle speed when the half-fastening control is performed is lower than that when the half-fastening control is not performed. .. In other words, the vehicle speed (solid line) when the half-engagement control is performed by the power generation vehicle control is compared with the vehicle speed (one-dot chain line) when the half-engagement control is not performed, and the vehicle is when the power generation vehicle control is not performed. It changes by a value closer to the vehicle speed (broken line) when 1 is coasting.

At time t5, when the engine rotation speed converges to the idle rotation speed Ni, the ECU 100 causes the TCU 300 to perform engagement control to change the forward clutch 31 from the semi-engaged state to the engaged state.

By the way, it is assumed that the fuel cut control is omitted even if the vehicle 1 shifts to coasting due to the specifications of the vehicle 1 or because the start condition of the fuel cut control is not satisfied. The internal operation of the vehicle 1 when the process related to the vehicle control for power generation is performed when the fuel cut control is omitted will be described with reference to FIG.

FIG. 8 shows an example of the internal operation of the vehicle 1 by the process related to the power generation vehicle control when the fuel cut control is omitted. As is clear from FIG. 8, when the vehicle 1 starts coasting due to the change from accelerator on to accelerator off at time t1, the fuel cut control is omitted and the operation shifts to the operation at time t2 in FIG. That is, as shown in FIG. 8, since the SOC of the vehicle-mounted battery 50 is less than the lower limit and the vehicle 1 is running, the oil temperature of the transmission 30 is less than the threshold value and the rotation speed sensor 79A. If 79B is normal, the ECU 100 sets the power generation vehicle control permission flag indicating the permission for power generation vehicle control to the ON state. Then, the ECU 100 first causes the TCU 300 to perform the semi-engagement control of the forward clutch 31 as the vehicle control for power generation. Due to this semi-fastening control, a speed difference is generated between the first rotation speed (solid line) and the second rotation speed (broken line).

At time t2, when the ECU 100 determines that the forward clutch 31 is in the semi-engaged state, the current engine rotation speed is the target engine rotation speed Nt required to rotate the generator 60 at the maximum efficiency rotation speed Nmax. The control of the engine rotation speed is started so as to be.

When the SOC of the vehicle-mounted battery 50 becomes equal to or higher than the lower limit value at time t3, the ECU 100 changes the power generation vehicle control permission flag from the on state to the off state to prohibit power generation vehicle control. As a result, the ECU 100 ends the control for matching the engine rotation speed with the target engine rotation speed Nt, and starts the idle control.

At times t2 to t3, the engine rotation speed increases and is maintained up to the target engine rotation speed Nt, so that the SOC of the vehicle-mounted battery 50 increases at a larger rate of change than before time t2.

Further, at times t2 to t3, although the first rotation speed increases by increasing and maintaining the engine rotation speed up to the target engine rotation speed Nt, the second rotation speed is increased because the semi-fastening control is performed. The rise is suppressed. Further, as in FIG. 7, the vehicle speed (solid line) when the half-engagement control is performed by the power generation vehicle control is compared with the vehicle speed (one-dot chain line) when the half-engagement control is not performed, and the power generation vehicle control is performed. If not, the value changes closer to the vehicle speed (broken line) when the vehicle 1 is coasting. Since the subsequent operations are the same as those in FIG. 7, the description thereof will be omitted.

According to such a vehicle control device, when the predetermined condition is satisfied regardless of the presence or absence of the fuel cut control while the vehicle 1 is coasting, the generator 60 is set to the maximum efficiency while the forward clutch 31 is in the semi-engaged state. The vehicle for power generation is controlled to rotate at the rotation speed Nmax. As a result, the vehicle speed when the half-engagement control is performed by the power generation vehicle control is compared with the vehicle speed when the half-engagement control is not performed, and the vehicle 1 is coasting when the power generation vehicle control is not performed. It changes at a value closer to the vehicle speed at that time. Therefore, during coasting of the vehicle 1, it is possible to suppress a change in vehicle speed different from that during coasting of the vehicle while rotating the generator 60 at the maximum efficient rotation speed Nmax by controlling the engine rotation speed.

In the power generation vehicle control permission determination routine of FIG. 3, it is determined that the power generation vehicle control can be permitted when the measured value N of the engine rotation speed is less than the target engine rotation speed Nt, and the measured value N of the engine rotation speed N. May add a process for prohibiting vehicle control for power generation when the target engine rotation speed is Nt or more. When the vehicle control for power generation is prohibited by this process, the throttle valve 15 is kept in the fully closed state, so that the engine rotation speed decreases to the target engine rotation speed Nt or the increase in the engine rotation speed is suppressed. Is possible. When determining the necessity of power generation vehicle control according to the target engine rotation speed Nt, the processes of S303 to S305 of FIG. 4 are incorporated in the power generation vehicle control permission determination routine. Since the vehicle control for power generation can be started when the current engine rotation speed becomes less than the target engine rotation speed Nt, the current engine rotation speed can be increased to the target engine rotation speed Nt by S306.

In S304 and S305 of FIG. 5, the target engine rotation speed Nt was set separately for when the battery temperature was relatively high and when the battery temperature was relatively low, but instead of this, three were set according to the battery temperature. It may be set separately as described above.

In the above embodiment, the ECU 100 controls the internal combustion engine 10 and the ACU 200 controls the generator 60. However, the ACU 200 is omitted and the ECU 100 controls the generator 60. May be good.

Although the processing related to the power generation vehicle control is described as being performed in the ECU 100, such processing may be performed in any of the ECU 100, the ACU 200, and the TCU 300. Further, processing related to power generation vehicle control may be performed in a control device different from the ECU 100, ACU 200, and TCU 300.

A control device in which at least two of the ECU 100, the ACU 200, and the TCU 300 are integrated may perform processing related to power generation vehicle control. For example, the ECU 100, in which the functions of the ACU 200 are integrated, can perform processing related to power generation vehicle control.

A continuously variable transmission using a CVT 32 is exemplified as the transmission 30 of the vehicle 1, but any transmission equipped with a forward clutch 31 can be applied as the transmission 30 of the vehicle 1, regardless of whether it is stepped or stepless. It is possible.

Although the forward clutch 31 is configured as a part of the transmission 30, instead of the forward clutch 31, a power disengagement mechanism equivalent to that of the forward clutch 31 is arranged between the internal combustion engine 10 and the drive wheel 40. May be good.

Although a 4-cycle engine is exemplified as the internal combustion engine 10, it may be a 2-cycle engine. Further, the output signals of various sensors required by the ECU 100 for processing related to power generation vehicle control may be directly input without going through the ACU 200 or the TCU 300.

Although the contents of the present invention have been specifically described with reference to the preferred embodiments, the technical ideas described above can be appropriately combined and used as long as there is no contradiction. Further, it is obvious that those skilled in the art can adopt various modifications based on the basic technical idea and teaching of the present invention.

1 ... Vehicle, 10 ... Internal engine, 30 ... Transmission, 31 ... Forward clutch, 31A ... Drive plate, 31B ... Driven plate, 50 ... In-vehicle battery, 60 ... Generator, N ... Engine rotation speed measurement value, Nmax ... Maximum efficiency rotation speed, Nt ... Target engine rotation speed, N1 ... First rotation speed measurement value, N2 ... Second rotation speed measurement value, T ... Battery temperature measurement value, SOC ... In-vehicle battery charge status

Claims (3)

The inertia of a vehicle including an internal combustion engine, a generator driven by the rotational output of the internal combustion engine, a transmission for transmitting the rotational output of the internal combustion engine to the drive wheels, and a battery charged by the generator. When the predetermined conditions including the charge state of the battery become less than the predetermined value are satisfied during traveling, the power generation efficiency of the generator is maximized while the forward clutch of the transmission is in the semi-engaged state. A vehicle control device that controls the engine rotation speed so that it becomes. The internal combustion engine is controlled so that the measured value of the engine rotation speed becomes the target engine rotation speed which is the engine rotation speed when the power generation efficiency of the generator is maximized, and the target engine rotation speed is set to that of the generator. The vehicle control device according to claim 1, which is set according to the ambient temperature. The vehicle control device according to claim 1 or 2, wherein when the forward clutch is in the semi-engaged state, the engaging pressure of the forward clutch is reduced as the state of charge of the battery rises.

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