JP5267102B2 - Vehicle control device - Google Patents

Description

  The present invention is applied to an engine vehicle, a hybrid vehicle, an electric vehicle, and the like, and relates to a vehicle control device having a mode in which a friction clutch interposed between a drive source and a drive wheel runs in a slip engagement state.

A conventional vehicle clutch control device is interposed between an engine and a motor / generator, and is interposed between a motor / generator and drive wheels, a first fastening element that connects and disconnects the engine and the motor / generator, and a motor. The second fastening element for connecting / disconnecting the generator and the drive wheel, the first traveling mode in which the first fastening element is opened, the second fastening element is fastened and the vehicle travels only by the driving force of the motor, the first fastening element and the first 2 Fastening elements are fastened and the 2nd driving mode which runs with the driving force of both the engine and the motor / generator, the 1st fastening element is fastened and the 2nd fastening element is slip-fastened, and both the engine and the motor / generator The third traveling mode in which the vehicle is driven by the driving force is switched according to the traveling state. Then, the temperature detection means for detecting the temperature of the second fastening element switches to the first traveling mode when starting from the vehicle stop state and the temperature of the second fastening element is equal to or higher than a predetermined value. It is known (see, for example, Patent Document 1).
JP 2007-314097

  However, in the conventional vehicle clutch control device, the first engagement element is engaged, the second engagement element is slip-engaged, and a command is issued to travel in the third traveling mode by the driving force of both the engine and the motor / generator. However, when the temperature of the second fastening element is equal to or higher than the predetermined value, the first fastening element is opened, the second fastening element is fastened, and the vehicle travels in the first travel mode only with the driving force of the motor. Therefore, there is a problem that a shock associated with the release / engagement of the clutch is generated, and there is a possibility that the intended traveling may not be realized due to loss of driving force.

  The present invention has been made paying attention to the above problem, and provides a vehicle control device that can ensure heat generation durability of a friction clutch while realizing a driving intended by a driver without occurrence of a shock. With the goal.

In order to achieve the above object, in the vehicle control apparatus of the present invention, a friction clutch is interposed between the drive source and the drive wheel, and the friction clutch is brought into a slip-engaged state in a low vehicle speed range including the vehicle stop. Slip engagement travel control means for traveling while controlling the clutch torque capacity so as to obtain a required drive torque determined according to the state and driver operation.
The control apparatus for a vehicle, a clutch heating load detecting means for detecting a heating load of the friction clutch, and the accelerator opening detection means for detecting an accelerator opening, vehicle speed detecting means for detecting a vehicle speed, Ru provided.
The slip engagement travel control means sets the target input rotational speed of the friction clutch to a value smaller than the target input rotational speed calculated based on the accelerator opening and the vehicle speed as the heat load detection value of the friction clutch increases. Thus, control is performed to suppress the slip amount, which is the differential rotation between the input rotation speed and the output rotation speed , of the friction clutch.

Therefore, in the vehicle control device of the present invention, when starting or running in a low vehicle speed range including the vehicle stop, the friction clutch is set to the slip engagement state, and the required driving torque determined according to the vehicle state and the driver operation Thus, slip engagement traveling control is performed in which the vehicle travels while controlling the clutch torque capacity. In this slip engagement running control, the slip amount, which is the differential rotation between the input rotational speed and the output rotational speed of the friction clutch, is reduced as the detected value of the heat generation load of the friction clutch indicates a larger heat generation load.
That is, in order to avoid heat generation of the friction clutch, the slip engagement running control is maintained as it is without performing operations such as clutch release and engagement, so there is no shock due to clutch release / engagement, and the driver intends Travel is realized. Furthermore, the amount of heat generated by the friction clutch can be reduced by reducing the slip amount of the friction clutch as the value indicates a larger heat generation load.
As a result, it is possible to ensure the heat generation durability of the friction clutch while realizing the driving intended by the driver without occurrence of shock.
In addition, the target input rotational speed of the friction clutch is set to a value smaller than the target input rotational speed calculated based on the accelerator opening and the vehicle speed, as the heat clutch load detection value is larger. For this reason, the overall characteristics of the target input speed due to the accelerator opening and the vehicle speed change due to shift movement depending on the size of the heat generation load. Increase and decrease can be controlled.

  Hereinafter, the best mode for realizing a vehicle control apparatus of the present invention will be described based on a first embodiment shown in the drawings.

First, the configuration will be described.
FIG. 1 is an overall system diagram showing a rear-wheel drive FR hybrid vehicle (an example of a vehicle) to which the control device of the first embodiment is applied.

  As shown in FIG. 1, the drive system of the FR hybrid vehicle in the first embodiment includes an engine Eng (drive source), a flywheel FW, a first clutch CL1, a motor / generator MG (drive source), and a second drive system. Clutch CL2 (friction clutch), automatic transmission AT, propeller shaft PS, differential DF, left drive shaft DSL, right drive shaft DSR, left rear wheel RL (drive wheel), right rear wheel RR ( Drive wheel). Note that FL is the left front wheel and FR is the right front wheel.

  The engine Eng is a gasoline engine or a diesel engine, and engine start control, engine stop control, and throttle valve opening control are performed based on an engine control command from the engine controller 1. The engine output shaft is provided with a flywheel FW.

  The first clutch CL1 is a clutch interposed between the engine Eng and the motor / generator MG, and is generated by the first clutch hydraulic unit 6 based on a first clutch control command from the first clutch controller 5. Engagement / release is controlled by the first clutch control hydraulic pressure including the half clutch state. As the first clutch CL1, for example, a dry single-plate clutch whose engagement / release is controlled by a hydraulic actuator 14 having a piston 14a is used.

  The motor / generator MG is a synchronous motor / generator in which a permanent magnet is embedded in a rotor and a stator coil is wound around a stator, and a three-phase AC generated by an inverter 3 based on a control command from the motor controller 2. It is controlled by applying. The motor / generator MG can operate as an electric motor that is driven to rotate by receiving power supplied from the battery 4 (hereinafter, this operation state is referred to as “powering”), and the rotor is driven from the engine Eng or the drive wheel. When receiving rotational energy, it functions as a generator that generates electromotive force at both ends of the stator coil, and can also charge the battery 4 (hereinafter, this operation state is referred to as “regeneration”). Note that the rotor of the motor / generator MG is connected to the transmission input shaft of the automatic transmission AT via a damper.

  The second clutch CL2 is a clutch interposed between the motor / generator MG and the left and right rear wheels RL, RR. Based on the second clutch control command from the AT controller 7, the second clutch hydraulic unit 8 By the control hydraulic pressure generated by the above, the fastening / opening is controlled including slip fastening and slip opening. As the second clutch CL2, for example, a wet multi-plate clutch or a wet multi-plate brake capable of continuously controlling the oil flow rate and hydraulic pressure with a proportional solenoid is used. The first clutch hydraulic unit 6 and the second clutch hydraulic unit 8 are built in an AT hydraulic control valve unit CVU attached to the automatic transmission AT.

  The automatic transmission AT is, for example, a stepped transmission that automatically switches stepped speeds such as forward 7 speed / reverse speed 1 according to vehicle speed, accelerator opening, etc., and the second clutch CL2 However, it is not newly added as a dedicated clutch, but the most suitable clutch or brake arranged in the torque transmission path is selected from a plurality of frictional engagement elements that are engaged at each gear stage of the automatic transmission AT. . The output shaft of the automatic transmission AT is connected to the left and right rear wheels RL and RR via a propeller shaft PS, a differential DF, a left drive shaft DSL, and a right drive shaft DSR.

  The hybrid drive system of the first embodiment includes an electric vehicle travel mode (hereinafter referred to as “EV mode”), a hybrid vehicle travel mode (hereinafter referred to as “HEV mode”), and a CL2 slip engagement travel mode (hereinafter referred to as “ It has a driving mode such as “WSC mode”.

  The “EV mode” is a mode in which the first clutch CL1 is opened and the vehicle travels only with the power of the motor / generator MG. The “HEV mode” is a mode in which the first clutch CL1 is engaged and the vehicle travels in any one of the engine travel mode, the motor assist travel mode, and the travel power generation mode. The “WSC mode” is, for example, a low vehicle speed range including a vehicle stop when starting from “EV mode”, starting from “HEV mode”, or traveling on an uphill road in “HEV mode”. The second clutch CL2 is brought into the slip engagement state, and the clutch transmission capacity is controlled so that the clutch transmission torque passing through the second clutch CL2 becomes the required driving torque determined according to the vehicle state and the driver operation. It is a running mode. “WSC” is an abbreviation for “Wet Start Clutch”.

Next, the control system of the hybrid vehicle will be described.
As shown in FIG. 1, the control system of the FR hybrid vehicle in the first embodiment includes an engine controller 1, a motor controller 2, an inverter 3, a battery 4, a first clutch controller 5, and a first clutch hydraulic unit 6. And an AT controller 7, a second clutch hydraulic unit 8, a brake controller 9, and an integrated controller 10. The engine controller 1, the motor controller 2, the first clutch controller 5, the AT controller 7, the brake controller 9, and the integrated controller 10 are connected via a CAN communication line 11 that can mutually exchange information. ing.

  The engine controller 1 inputs engine speed information from the engine speed sensor 12, a target engine torque command from the integrated controller 10, and other necessary information. Then, a command for controlling the engine operating point (Ne, Te) is output to the throttle valve actuator or the like of the engine Eng.

  The motor controller 2 inputs information from the resolver 13 that detects the rotor rotational position of the motor / generator MG, a target MG torque command and a target MG rotational speed command from the integrated controller 10, and other necessary information. Then, a command for controlling the motor operating point (Nm, Tm) of the motor / generator MG is output to the inverter 3. The motor controller 2 monitors the battery SOC representing the charge capacity of the battery 4, and this battery SOC information is used as control information for the motor / generator MG and is integrated via the CAN communication line 11. 10 is supplied.

  The first clutch controller 5 inputs sensor information from the first clutch stroke sensor 15 that detects the stroke position of the piston 14a of the hydraulic actuator 14, a target CL1 torque command from the integrated controller 10, and other necessary information. . Then, a command for controlling engagement / disengagement of the first clutch CL1 is output to the first clutch hydraulic unit 6 in the AT hydraulic control valve unit CVU.

  The AT controller 7 receives information from an accelerator opening sensor 16 (accelerator opening detecting means), a vehicle speed sensor 17 (vehicle speed detecting means), and other sensors 18 (transmission input rotation speed sensor, inhibitor switch, etc.). Enter. Then, when driving with the D range selected, a control command for obtaining the searched gear position is searched for the optimum gear position based on the position where the operating point determined by the accelerator opening APO and the vehicle speed VSP exists on the shift map. Output to AT hydraulic control valve unit CVU. The shift map is a map in which an upshift line and a downshift line are written according to the accelerator opening and the vehicle speed. In addition to the above automatic shift control, when a target CL2 torque command is input from the integrated controller 10, a command for controlling engagement / release of the second clutch CL2 is output to the second clutch hydraulic unit 8 in the AT hydraulic control valve unit CVU. The second clutch control is performed.

  The brake controller 9 inputs a wheel speed sensor 19 for detecting the wheel speeds of the four wheels, sensor information from the brake stroke sensor 20, a regenerative cooperative control command from the integrated controller 10, and other necessary information. And, for example, at the time of brake depression, if the regenerative braking force is insufficient with respect to the required braking force required from the brake stroke BS, the shortage is compensated with mechanical braking force (hydraulic braking force or motor braking force) Regenerative cooperative brake control is performed.

  The integrated controller 10 manages the energy consumption of the entire vehicle and has a function for running the vehicle with the highest efficiency. The integrated controller 10 detects a motor rotation speed Nm, and other sensors and switches 22. The necessary information from the clutch temperature sensor 23 (clutch heat generation load detection means) for detecting the temperature of the second clutch CL2, the road surface gradient sensor 24 (clutch heat generation load detection means) for detecting the traveling road surface gradient, and the CAN communication line 11 Enter information via. The target engine torque command to the engine controller 1, the target MG torque command and the target MG speed command to the motor controller 2, the target CL1 torque command to the first clutch controller 5, the target CL2 torque command to the AT controller 7, and the brake controller 9 Regenerative cooperative control command is output.

  FIG. 2 is a control block diagram illustrating arithmetic processing executed by the integrated controller 10 of the FR hybrid vehicle to which the control device of the first embodiment is applied. FIG. 3 is a diagram illustrating an EV-HEV selection map used when performing a mode selection process in the integrated controller 10 of the FR hybrid vehicle to which the control device of the first embodiment is applied. FIG. 4 is a diagram illustrating a target charge / discharge amount map used when battery charge control is performed by the integrated controller 10 of the FR hybrid vehicle to which the control device of the first embodiment is applied. Hereinafter, based on FIGS. 2-4, the arithmetic processing performed in the integrated controller 10 of Example 1 is demonstrated.

  As shown in FIG. 2, the integrated controller 10 includes a target driving force calculation unit 100, a mode selection unit 200, a target charge / discharge calculation unit 300, and an operating point command unit 400.

  The target driving force calculation unit 100 calculates a target driving force tFoO from the accelerator opening APO and the vehicle speed VSP using the target driving force map.

  The mode selection unit 200 uses the EV-HEV selection map shown in FIG. 3 to select “EV mode” or “HEV mode” as the target travel mode from the accelerator opening APO and the vehicle speed VSP. However, if the battery SOC is equal to or lower than the predetermined value, the “HEV mode” is forcibly set as the target travel mode. Further, when starting from the “EV mode” or “HEV mode”, the “WSC mode” is selected as the target travel mode until the vehicle speed VSP reaches the first set vehicle speed VSP1.

  The target charge / discharge calculation unit 300 calculates the target charge / discharge power tP from the battery SOC using the target charge / discharge amount map shown in FIG.

  In the operating point command unit 400, based on input information such as the accelerator opening APO, the target driving force tFoO, the target travel mode, the vehicle speed VSP, the target charge / discharge power tP, etc., the target engine torque is set as the operating point reaching target. And target MG torque, target MG rotation speed, target CL1 torque, and target CL2 torque. Then, the target engine torque command, the target MG torque command, the target MG rotational speed command, the target CL1 torque command, and the target CL2 torque command are output to the controllers 1, 2, 5, and 7 via the CAN communication line 11.

  FIG. 5 is a flowchart showing a flow of slip engagement travel control processing at the time of start / travel when the “WSC mode” is selected in the engaged state of the first clutch CL1 executed by the integrated controller 10 of the first embodiment. (Slip fastening travel control means). Hereinafter, each step of the flowchart of FIG. 5 will be described.

  In step S101, it is determined whether or not the currently selected travel mode is “WSC mode” (= slip engagement travel mode). If YES (when “WSC mode” is selected), the process proceeds to step S102. In the case of NO (when a driving mode other than “WSC mode” is selected), the determination in step S101 is repeated.

  In step S102, following the determination that the “WSC mode” is selected in step S101, the vehicle speed VSP from the vehicle speed sensor 17, the accelerator opening APO from the accelerator opening sensor 16, and the second from the clutch temperature sensor 23 are displayed. The clutch temperature, the road surface gradient from the road surface gradient sensor 24, and the minimum engine speed are read, and the process proceeds to step S103.

In step S103, following the reading of necessary information in step S102, the target input rotational speed to the automatic transmission AT is calculated from the vehicle speed VSP and the accelerator opening APO, and the process proceeds to step S104.
Here, as shown in the target input rotational speed map of FIG. 6, the “target input rotational speed” indicates that the target input rotational speed increases as the vehicle speed VSP increases and the accelerator opening APO increases. The target input rotational speed is calculated to a value that decreases as the number increases and the accelerator opening APO decreases. In FIG. 6, the differential speed zero characteristic in which the output speed is converted into the input speed from the vehicle speed VSP (= transmission output speed) and the gear ratio in the automatic transmission AT is written. When the differential rotation zero characteristic is crossed due to the increase in the value, the target input rotational speed is calculated along the differential rotation zero characteristic. In other words, the differential rotation is maximized when the vehicle speed VSP is zero, and is set to a target input rotational speed at which the differential rotation converges to zero as the vehicle speed VSP increases.

In step S104, following the calculation of the target input rotational speed in step S103, the target input rotational speed gain is calculated from the second clutch temperature and the road surface gradient, and the process proceeds to step S105.
Here, as shown in the target input speed gain characteristic of FIG. 7, the “target input speed gain” is set to a smaller value of 1 or less as the second clutch temperature is higher. Further, when the second clutch temperature is the same value, the detected road surface gradient detected value from the road surface gradient sensor 24 is a value indicating a large gradient resistance, which is a smaller value of 1 or less.

In step S105, following the calculation of the target input rotational speed gain in step S104, the target input rotational speed calculated in step S103 is multiplied by the target input rotational speed gain calculated in step S104, thereby gain multiplication target input rotational speed. The number is calculated, and the process proceeds to step S106.
This “gain multiplication target input speed” is the same value as the target input speed calculated in step S103 when the target input speed gain is 1, but zero when the target input speed gain is less than 1. As the value approaches, the value becomes smaller than the target input rotational speed calculated in step S103. That is, control is performed to suppress the slip amount, which is the differential rotation between the input rotation and the output rotation of the second clutch CL2.

  In step S106, following the calculation of the gain multiplication target input rotation speed in step S105, the final target input rotation speed is set by selecting high of the calculated gain multiplication target input rotation speed and the engine minimum rotation speed, and the process proceeds to step S107. move on.

In step S107, following the setting of the final target input rotational speed in step S106, a clutch torque for realizing the final target input rotational speed is calculated, and a target CL2 torque command for obtaining the calculated clutch torque is output to the second clutch CL2. The process proceeds to step S108.
Note that the control for following the input rotational speed of the second clutch CL2 in accordance with the final target input rotational speed is performed by rotational speed control by the motor / generator MG.

  In step S108, following the output of the target CL2 torque command in step S107, it is determined whether or not the selected travel mode is “WSC mode”. If YES (when “WSC mode” is selected), Returning to step S102, if NO (when a travel mode other than “WSC mode” is selected), the process proceeds to return.

Next, the operation will be described.
The effects of the vehicle control apparatus according to the first embodiment are “slip engagement travel control processing operation when“ WSC mode ”is selected”, “slip engagement travel control operation when the clutch heat generation load is low”, and “clutch heat generation load is high” "Slip fastening travel control action" will be described separately.

[Slip fastening travel control processing when "WSC mode" is selected]
Hereinafter, based on the flowchart shown in FIG. 5, the operation of the slip fastening travel control process when the “WSC mode” is selected will be described.

  When “WSC mode” is selected as the travel mode when the first clutch CL1 is engaged, such as when starting or running on an uphill road at a low speed, in the flowchart of FIG. 6, step S101 → step S102 → Step S103 → Step S104 → Step S105 → Step S106 → Step S107 → Step S108. As long as the selection of “WSC mode” is maintained, the flow of steps S102 → step S103 → step S104 → step S105 → step S106 → step S107 → step S108 is repeated.

  That is, when the necessary information is read in step S102, in the next step S103, the target input rotational speed to the automatic transmission AT is calculated from the vehicle speed VSP and the accelerator opening APO. In the next step S104, the target input rotational speed gain is calculated from the second clutch temperature and the road surface gradient. In the next step S105, the target input rotational speed calculated in step S103 is multiplied by the target input rotational speed gain calculated in step S104, thereby calculating the gain multiplied target input rotational speed. In the next step S106, the final target input rotational speed is set by selecting high of the calculated gain multiplication target input rotational speed and the engine minimum rotational speed. In the next step S107, a clutch torque that achieves the final target input rotational speed is calculated, and a target CL2 torque command for obtaining the calculated clutch torque is output to the second clutch CL2.

  Therefore, when “WSC mode” is selected in the engaged state of the first clutch CL1, the vehicle speed VSP, the accelerator opening APO, the second clutch temperature, the road surface gradient, and the minimum engine speed are read at every calculation processing cycle. The final target input rotational speed of the automatic transmission AT is set according to the change in information. Then, by the rotational speed control of the motor / generator MG, slip control is performed to ensure the differential rotation of the second clutch CL2 required by causing the actual input rotational speed of the automatic transmission AT to follow the final target input rotational speed. Then, the torque capacity control of the second clutch CL2 is performed with the clutch torque realizing the final target input rotational speed. When the final target input rotational speed to the automatic transmission AT becomes the rotational speed at which the differential rotation of the second clutch CL2 is eliminated, the second clutch CL2 shifts from slip engagement to complete engagement, and the travel mode is “ Mode transition from “WSC mode” to “HEV mode”.

[Slip engagement travel control action when clutch heat generation load is low]
The slip engagement travel control operation when the clutch heat generation load is low, such as at the initial start from a flat road in the “HEV mode”, will be described.

  First, since the second clutch temperature is a low value and the traveling road surface gradient detection value is a value indicating a small gradient resistance, as shown in the target input rotation gain characteristic of FIG. "Is set to a value of 1.

  When the accelerator pedal opening APO is large at the start of the depression, a high target input speed characteristic is selected from the target input speed map in FIG. 6, so that the “target input speed” is the vehicle speed from the stop state. It is set to a value that increases as VSP increases.

  Therefore, as the final target input speed, the “target input speed” calculated from the accelerator opening APO and the vehicle speed VSP is used as it is, and the second clutch CL2 is used when the vehicle speed VSP at the start of start is zero. The differential rotation gradually decreases as the vehicle speed VSP increases after starting, and when the vehicle reaches a predetermined vehicle speed and shifts to the running state, the differential rotation converges to zero and the second clutch CL2 is completely The engaged state is entered, and the travel mode transitions from “WSC mode” to “HEV mode”.

  For this reason, for example, in the case of an FR hybrid vehicle that does not have a torque converter as in the first embodiment, the second clutch CL2 built in the existing automatic transmission AT is slip-engaged to maintain the slip-engaged state. While absorbing the torque by the clutch slip, the drive torque can be raised smoothly by the torque capacity control of the second clutch CL2, and the vehicle can be started smoothly as in the case of the vehicle with the torque converter.

[Slip engagement travel control action when clutch heat generation load is high]
FIG. 8 is a characteristic diagram showing the relationship between the input rotational speed and the vehicle speed for explaining the effect of reducing the clutch heat generation amount by adjusting the target input rotational speed gain in the FR hybrid vehicle of the first embodiment. Hereinafter, the slip engagement travel control operation when the clutch heat generation load is high will be described with reference to FIG.

  In the FR hybrid vehicle having the “WSC mode” in which the second clutch CL2 built in the existing automatic transmission AT is slipped and started and traveled as in the first embodiment, a number of traffic lights are installed. The second clutch CL2 is brought into a continuous slip state when the start and stop are repeated in an urban area or when the vehicle is running on an uphill slope. In such a traveling situation, there is a problem that the μ-V characteristic of the friction material due to heat generation of the second clutch CL2 deteriorates and vehicle vibration (judder) occurs.

  Here, the μ-V characteristic refers to a change characteristic of the friction coefficient μ with respect to the sliding speed V. If a positive gradient is maintained, no vehicle vibration is observed, but the friction material μ-V characteristic is If a negative gradient (the friction coefficient μ decreases as the sliding speed V increases) due to deterioration, vehicle vibration (judder) may occur. In addition, since this vehicle vibration is self-excited vibration that gradually increases in amplitude, it is necessary to avoid degradation of the μ-V characteristics of the friction material due to heat generated by the second clutch CL2.

  On the other hand, in a vehicle having the “WSC mode”, when trying to guarantee the heat generation problem of the wet multi-plate clutch with the durability of the clutch, the oil lubrication flow rate for cooling the wet multi-plate clutch is increased or the driven plate is The heat capacity must be increased. Therefore, it is necessary to make a major modification to the unit, which increases the cost and unit layout.

  On the other hand, in order to avoid the heat generation of the clutch, if an attempt is made to avoid a temperature rise by an operation such as complete release or complete engagement of the wet multi-plate clutch, the clutch transmission torque is output as a driving force as it is. Therefore, the vehicle may jump out due to a sudden increase in driving force, the driving force may drop due to a sudden decrease in driving force, or the engine may stall due to a sudden increase in engine load.

  In the first embodiment, by detecting the temperature of the second clutch CL2 and the road surface gradient, the differential rotation (= slip amount) of the second clutch CL2 is controlled during traveling with the “WSC mode” selected. This is to avoid the deterioration of the μ-V characteristics of the friction material due to the heat generated by the two-clutch CL2.

  That is, as the second clutch temperature is higher, the target input speed gain is set to a smaller value of 1 or less as shown in the target input speed gain characteristic of FIG. Further, when the second clutch temperature is the same value, the target road speed gain characteristic of FIG. 7 indicates that the detected value of the road surface gradient from the road surface gradient sensor 24 indicates a larger gradient resistance. The input rotation speed gain is a small value of 1 or less.

  Then, the gain multiplication target input rotational speed becomes a value smaller than the target input rotational speed calculated from the accelerator opening APO and the vehicle speed VSP as it approaches zero when the target input rotational speed gain is less than 1. That is, control is performed to suppress the slip amount, which is the differential rotation between the input rotation and the output rotation of the second clutch CL2.

  FIG. 8 shows the influence on the amount of heat generated by the clutch when the slip engagement control of the first embodiment is performed. As the actual second clutch temperature rises due to repeated slip engagement, etc., the gain multiplication target input speed decreases, and finally the gain multiplication target input speed becomes the engine minimum speed (= the minimum idle speed). Become. In addition, the gain multiplication target input rotational speed decreases as the second clutch temperature is predicted to increase due to long-time slip engagement on an uphill slope, and finally the gain multiplication target input rotational speed becomes the lowest engine speed. Number (= minimum idle speed).

  Therefore, by performing the slip engagement running control of the first embodiment, the clutch heat generation amount is reduced by the area of the hatched portion surrounded by the input rotation speed characteristic before gain multiplication and the input rotation speed characteristic after gain multiplication in FIG. The temperature increase of the second clutch CL2 can be suppressed.

  Furthermore, when the vehicle is running on an uphill slope road, it is an uphill slope road, so that the clutch temperature rise due to the long-time slip engagement can be suppressed by predicting the clutch temperature rise, and the second clutch temperature is actually increased by the long-time slip engagement. When the temperature rises, the increase in the clutch temperature is effectively suppressed by the reduction in the target input speed gain based on the factors of both the gradient resistance and the second clutch temperature.

  As a result, the increase in the surface temperature of the friction material of the second clutch CL2 can be suppressed, so that the μ-V characteristic deterioration of the clutch friction material can be avoided, and the vehicle vibration caused by the μ-V characteristic deterioration can be avoided. Can be prevented. In addition, in order to ensure the durability of the second clutch CL2, it is not necessary to reinforce the second clutch CL2 by increasing the clutch lubrication flow rate or increasing the number of driven plates, thereby avoiding an increase in repair costs and an increase in the overall unit length. .

In the first embodiment, the final target input rotation speed is set to a value selected as a high selection of the gain multiplication target input rotation speed and the engine minimum rotation speed.
Therefore, it is possible to prevent the engine target rotational speed after gain multiplication from being equal to or lower than the engine idle rotational speed and causing engine stall.

Next, the effect will be described.
In the control device for the FR hybrid vehicle of the first embodiment, the effects listed below can be obtained.

  (1) A friction clutch (second clutch CL2) is interposed between the drive source (engine Eng, motor / generator MG) and the drive wheels (left and right rear wheels RL, RR). A control apparatus for a vehicle (FR hybrid vehicle) having slip engagement travel control means that travels while controlling the clutch torque capacity so that the friction clutch is in a slip engagement state and a required drive torque determined according to the vehicle state and driver operation. And a clutch heat generation load detection means (clutch temperature sensor 23, road surface gradient sensor 24) for detecting the heat generation load of the friction clutch, and the slip engagement travel control means (FIG. 5) is a heat generation load detection value of the friction clutch. Is a value indicating a large heat generation load, the smaller the slip amount, which is the difference between the input rotational speed and the output rotational speed of the friction clutch, is reduced. The obtaining control is carried out. For this reason, it is possible to ensure the heat generation durability of the friction clutch (second clutch CL2) while realizing the travel intended by the driver without occurrence of shock.

  (2) The clutch heat generation load detection means is a clutch temperature sensor 23 for detecting a clutch temperature of the friction clutch (second clutch CL2), and the slip engagement travel control means (FIG. 5) is a clutch of the friction clutch. As the detected temperature value is larger, control is performed to reduce the slip amount of the friction clutch. For this reason, when the clutch temperature is high, an increase in the clutch temperature can be suppressed with good response. As a result, it is effective when traveling in urban areas where start and stop are frequently repeated within a short time.

  (3) The clutch heat generation load detecting means is a road surface gradient sensor 24 that detects a traveling road surface gradient, and the slip engagement traveling control means (FIG. 5) is a value indicating that the traveling road surface gradient detected value indicates a large gradient resistance. The more the control is performed, the smaller the slip amount of the friction clutch (second clutch CL2) is. For this reason, by predicting the clutch temperature rise, the clutch temperature rise gradient can be suppressed to a gentle gradient even if slip engagement is performed for a long time. As a result, it is effective when running on an uphill slope.

  (4) An accelerator opening detecting means (accelerator opening sensor 16) for detecting the accelerator opening and a vehicle speed detecting means (vehicle speed sensor 17) for detecting the vehicle speed are provided, and the slip fastening traveling control means (FIG. 5). Calculates the target input rotational speed of the friction clutch (second clutch CL2) based on the accelerator opening APO and the vehicle speed VSP (step S103). The larger the heat load detection value of the friction clutch, the smaller the value is 1 or less. A target input rotational speed gain is calculated according to a value (step S104), and a gain multiplication target input rotational speed is obtained by multiplying the target input rotational speed gain and the target input rotational speed (step S105). By outputting a clutch torque control command that realizes the input rotational speed, control is performed to reduce the slip amount of the friction clutch. For this reason, the target input speed overall characteristics based on the accelerator opening APO and the vehicle speed VSP change due to the shift movement with the target input speed gain, and when there is a gain fluctuation, the gain multiplication target input speed changes smoothly. The number of differential rotations can be controlled by the number.

  (5) The drive source is a drive source having an engine Eng, and the slip fastening travel control means (FIG. 5) selects a value obtained by selecting high among the gain multiplication target input rotational speed and the engine minimum rotational speed as a final target. By setting the input rotational speed and outputting a clutch torque control command that realizes the final target input rotational speed, control is performed to suppress the slip amount of the friction clutch (second clutch CL2). For this reason, it is possible to prevent engine stall due to execution of slip engagement traveling control that controls the differential rotation of the friction clutch (second clutch CL2).

  As mentioned above, although the vehicle control apparatus of the present invention has been described based on the first embodiment, the specific configuration is not limited to the first embodiment, and the invention according to each claim of the claims. Design changes and additions are allowed without departing from the gist.

  In the first embodiment, the configuration of the FR hybrid vehicle includes an engine Eng, a first clutch CL1, a motor / generator MG, and a second clutch CL2 (built in the automatic transmission AT). However, it is not limited to the configuration shown in FIG. 1, and a continuously variable transmission may be used instead of the automatic transmission AT. Further, a new clutch may be provided on either the input shaft or the output shaft of the transmission as the second clutch CL2 (friction clutch).

  In the first embodiment, the clutch temperature sensor and the road surface gradient sensor are shown as the clutch heat generation load detecting means. However, if the clutch heat generation load detecting means is a means for detecting a factor affecting the clutch heat generation load, in addition to the clutch temperature sensor and the road surface gradient sensor, other than the heat generation amount estimation means by integrating the slip amount and the slip time, etc. The detection means can also be used.

  In the first embodiment, the application example to the FR hybrid vehicle in which the first clutch is interposed between the engine and the motor / generator and the second clutch is interposed between the motor / generator and the driving wheel is shown. However, it can also be applied to various other types of hybrid vehicles that have an engine and motor as a drive source, engine vehicles that have only an engine as a drive source, and electric vehicles and fuel cell vehicles that have only a motor as a drive source. can do. In short, the present invention can be applied to a vehicle having a slip engagement running mode by interposing a friction clutch between a drive source and a drive wheel.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an overall system diagram showing an FR hybrid vehicle (an example of a vehicle) by rear wheel drive to which a vehicle control device of Example 1 is applied. It is a control block diagram which shows the arithmetic processing performed in the integrated controller 10 of the FR hybrid vehicle to which the control apparatus of Example 1 was applied. It is a figure which shows the EV-HEV selection map used when performing the mode selection process with the integrated controller 10 of the FR hybrid vehicle to which the control apparatus of Example 1 is applied. It is a figure which shows the target charging / discharging amount map used when performing a battery charging / discharging process with the integrated controller 10 of the FR hybrid vehicle to which the control apparatus of Example 1 was applied. 6 is a flowchart illustrating a flow of slip engagement travel control processing at the time of start / travel when the “WSC mode” is selected in the engaged state of the first clutch CL1 executed by the integrated controller 10 of the first embodiment. It is a figure which shows the target input rotation speed map which uses as a parameter accelerator opening APO and vehicle speed VSP which are used in the slip fastening traveling control process performed in the integrated controller 10 of Example 1. FIG. It is a figure which shows the target input rotation speed gain map which uses as a parameter the 2nd clutch temperature and gradient resistance which are used in the slip engagement driving | running | working control processing performed in the integrated controller 10 of Example 1. FIG. FIG. 6 is a characteristic diagram showing the relationship between the input rotational speed and the vehicle speed for explaining the effect of reducing the clutch heat generation amount by adjusting the target input rotational speed gain in the FR hybrid vehicle of the first embodiment.

Explanation of symbols

Eng engine (drive source)
MG motor / generator (drive source)
CL1 1st clutch
CL2 2nd clutch (friction clutch)
RL Left rear wheel (drive wheel)
RR Right rear wheel (drive wheel)
1 engine controller 2 motor controller 3 inverter 4 battery 5 first clutch controller 6 first clutch hydraulic unit 7 AT controller 8 second clutch hydraulic unit 9 brake controller 10 integrated controller 16 accelerator opening sensor (accelerator opening detecting means)
17 Vehicle speed sensor (vehicle speed detection means)
23 Clutch temperature sensor (clutch heat generation load detection means)
24 Road surface gradient sensor (clutch heat load detection means)

Claims (5)

A friction clutch is interposed between the drive source and the drive wheel so that the friction clutch is slip-engaged in a low vehicle speed range including vehicle stop so that the required drive torque is determined according to the vehicle state and driver operation. In a vehicle control device having slip fastening travel control means that travels while controlling torque capacity,
Clutch heat generation load detection means for detecting the heat generation load of the friction clutch ;
An accelerator opening detecting means for detecting the accelerator opening;
Vehicle speed detecting means for detecting the vehicle speed , and
The slip engagement travel control means sets the target input rotational speed of the friction clutch to a value smaller than the target input rotational speed calculated based on the accelerator opening and the vehicle speed as the heat load detection value of the friction clutch increases. by the control device for a vehicle and performs an input rotation speed and output rotation speed reduced suppressing control slip amount is a rotational difference of the friction clutch. The vehicle control device according to claim 1,
The clutch heat generation load detecting means is a clutch temperature sensor that detects a clutch temperature of the friction clutch,
The vehicle control apparatus according to claim 1, wherein the slip engagement travel control unit performs control to reduce the slip amount of the friction clutch as the detected clutch temperature value of the friction clutch increases. In the vehicle control device according to claim 1 or 2,
The clutch heat generation load detecting means is a road surface gradient sensor that detects a traveling road surface gradient,
The vehicle control apparatus according to claim 1, wherein the slip engagement travel control unit performs control to reduce the slip amount of the friction clutch as the travel road surface slope detection value is a value indicating a greater slope resistance. In the control apparatus of the vehicle described in any one of Claims 1-3 ,
Before SL slip engagement travel control means calculates a target input rotational speed of the friction clutch by the accelerator opening and the vehicle speed, the target input rotation by more than one value smaller heating load detection value is a large value of the friction clutch A gain gain is calculated by multiplying the target input speed gain by the target input speed, and a clutch torque control command for realizing the gain multiplication target input speed is output. Thus, a control for suppressing the slip amount of the friction clutch is performed. The vehicle control device according to claim 4,
The drive source is a drive source having an engine,
The slip engagement travel control means sets a value by the select high among the gain multiplication target input speed and the engine minimum speed as the final target input speed, and outputs a clutch torque control command for realizing the final target input speed. Thus, a control for suppressing the slip amount of the friction clutch is performed.

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