JP5359300B2 - Control device for electric vehicle - Google Patents

Description

  The present invention is a control device for an electric vehicle that travels while maintaining a slip engagement state of a clutch interposed between a drive source and a drive wheel and controlling a clutch torque capacity when starting.

  Conventionally, a transmission disposed downstream of a drive source having a motor, and a clutch interposed between the drive source and the drive wheels, particularly when the battery SOC is low or the engine water temperature is low There is known a control device for an electric vehicle that executes WSC running control that starts with the clutch slipped (see, for example, Patent Document 1).

JP 2008-238836

By the way, depending on the traveling situation, an upshift (for example, a shift up from the first gear to the second gear) may be performed immediately after the vehicle has started. In this case, in the above-described conventional control device for an electric vehicle, after the clutch is slip-engaged and started, WSC lockup control is performed to lock-up the clutch, and the first gear is realized. Shift up to 2nd gear.
That is, in the conventional control apparatus for an electric vehicle, the WSC lockup control and the upshift control are in a so-called completely exclusive relationship in which the other control is started after the completion of one control, and a series of control ends. There was a problem that it took time.

  The present invention has been made paying attention to the above problems, and provides an electric vehicle control device capable of shortening the control time from the slip engagement state of the clutch at the time of start-up to the lock-up engagement and the subsequent start of the upshift. The purpose is to provide.

  In order to achieve the above object, in the present invention, a transmission that is arranged downstream of a drive source having a motor and achieves a plurality of shift stages by changing friction engagement elements, and at the time of start, a drive source and a drive wheel And a start control means for executing WSC running control for controlling the clutch torque capacity by maintaining the slip engagement state of the clutch interposed therebetween. A control unit, a lockup completion time prediction unit, and a carry-up upshift control unit. The WSC lockup control unit executes clutch engagement control for shifting the clutch from slip engagement to lockup engagement. The lockup completion time prediction unit predicts the time until the clutch lockup engagement is completed. Further, the carry-up upshift control unit starts the transmission upshift control at a timing earlier than the predicted clutch lockup engagement completion timing by the transmission upshift response time.

  Therefore, in the control apparatus for an electric vehicle according to the present invention, the upshift control can be started without waiting for the completion of the lockup engagement of the clutch that is slip-engaged at the start of the vehicle. It is possible to shorten the control time from the state to the lock-up engagement and the subsequent start of the upshift.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an overall system diagram showing an FR hybrid vehicle (an example of an electric vehicle) by rear wheel drive to which an electric vehicle control device of Embodiment 1 is applied. It is a control block diagram which shows the arithmetic processing performed with the integrated controller of FR hybrid vehicle to which the control apparatus of the electric vehicle of Example 1 was applied. It is a figure which shows the EV-HEV selection map used when performing the mode selection process in the integrated controller of FR hybrid vehicle to which the control apparatus of the electric vehicle of Example 1 is applied. It is a figure which shows the target charging / discharging amount map used when performing battery charge control with the integrated controller of FR hybrid vehicle to which the control apparatus of the electric vehicle of Example 1 was applied. 1 is a skeleton diagram illustrating an example of an automatic transmission mounted on an FR hybrid vehicle to which an electric vehicle control device according to a first embodiment is applied. FIG. It is a fastening operation | movement table | surface which shows the fastening state of each friction fastening element for every gear stage in the automatic transmission mounted in the FR hybrid vehicle to which the control apparatus of the electric vehicle of Example 1 was applied. 4 is a flowchart illustrating a flow of a start control process executed by the integrated controller according to the first embodiment. Accelerator opening, L / U mode, 1-2UP flag, AT output speed, WSC, L / U command oil pressure, 1-speed, explaining normal WSC lockup control action when shifting up to 1-2 speed from WSC mode It is a time chart which shows each characteristic of 2UP command oil pressure. It is a figure which shows the WSC lockup start map used when performing the start control process performed with the integrated controller of Example 1. FIG. It is explanatory drawing which shows the relationship between the 2nd clutch input rotational speed and the 2nd clutch output rotational speed in the case of the start control process performed in the integrated controller of Example 1. FIG.

  EMBODIMENT OF THE INVENTION Hereinafter, the form for implementing the control apparatus of the electric vehicle of this invention is demonstrated based on Example 1 shown in drawing.

First, the configuration will be described.
FIG. 1 is an overall system diagram showing a rear-wheel drive FR hybrid vehicle (an example of an electric 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, a flywheel FW, a first clutch CL1, a motor / generator MG, a second clutch CL2, and an automatic transmission AT. And a propeller shaft PS, a differential DF, a left drive shaft DSL, a right drive shaft DSR, a left rear wheel RL, and a right rear wheel RR. 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, throttle valve opening control, fuel cut control, and the like 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 / slip engagement (half-clutch state) / release is controlled by the first clutch control oil pressure. As the first clutch CL1, for example, a normally closed dry type in which a complete engagement is maintained by an urging force of a diaphragm spring and a stroke control using a hydraulic actuator 14 having a piston 14a is used to control from slip engagement to complete release. A single plate clutch 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 The fastening / slip fastening / release is controlled by the control hydraulic pressure generated by the above. As the second clutch CL2, for example, a normally open 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 drive torque control 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 motorist traveling mode, the traveling power generation mode, and the engine traveling mode. The "WSC mode" is used to control the rotational speed of the motor / generator MG when starting P, N → D selection from the "HEV mode" or starting the D range from the "EV mode" or "HEV mode". To maintain the slip engagement state of the second clutch CL2 and start while controlling the clutch torque capacity so that the clutch transmission torque passing through the second clutch CL2 becomes the required drive torque determined according to the vehicle state and driver operation. 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 / slip engagement / release 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 inputs information from an accelerator opening sensor 16, a vehicle speed sensor 17, and other sensors 18 (transmission input rotation speed sensor, inhibitor switch, etc.). 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 slip engagement of the second clutch CL2 is output to the second clutch hydraulic unit 8 in the AT hydraulic control valve unit CVU. Second clutch control is performed. Further, when the shift control change command is output from the integrated controller 10, the shift control according to the shift control change command is performed instead of the shift control normally.

  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 the motor rotation speed Nm, and the input rotation of the second clutch CL2. Necessary information from the second clutch input rotational speed sensor 22 for detecting the number NCL2in, the second clutch output rotational speed sensor 23 for detecting the output rotational speed NCL2out of the second clutch CL2, and other sensors and switches 24, and the CAN communication line 11 to input information. 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, at the time of P, N → D selection start from the “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 skeleton diagram illustrating an example of an automatic transmission AT mounted on an FR hybrid vehicle to which the control device of the first embodiment is applied.

  The automatic transmission AT is a stepped automatic transmission with 7 forward speeds and 1 reverse speed, and driving force from at least one of the engine Eng and the motor generator MG is input from the transmission input shaft Input, The rotational speed is changed by the planetary gear and the seven frictional engagement elements, and is output from the transmission output shaft Output. Next, a transmission gear mechanism between the transmission input shaft Input and the transmission output shaft Output will be described.

  The first planetary gear set GS1, the third planetary gear G3, and the fourth planetary gear G4 by the first planetary gear G1 and the second planetary gear G2 are sequentially arranged on the shaft from the transmission input shaft Input side to the transmission output shaft Output side. The second planetary gear set GS2 by is arranged. Further, a first clutch C1, a second clutch C2, a third clutch C3, a first brake B1, a second brake B2, a third brake B3, and a fourth brake B4 are arranged as friction engagement elements. Further, a first one-way clutch F1 and a second one-way clutch F2 are arranged.

  The first planetary gear G1 is a single pinion planetary gear having a first sun gear S1, a first ring gear R1, and a first carrier PC1 that supports a first pinion P1 that meshes with both gears S1, R1. .

  The second planetary gear G2 is a single pinion type planetary gear having a second sun gear S2, a second ring gear R2, and a second carrier PC2 that supports a second pinion P2 meshing with both gears S2 and R2. .

  The third planetary gear G3 is a single pinion planetary gear having a third sun gear S3, a third ring gear R3, and a third carrier PC3 that supports a third pinion P3 that meshes with both gears S3 and R3. .

  The fourth planetary gear G4 is a single pinion planetary gear having a fourth sun gear S4, a fourth ring gear R4, and a fourth carrier PC4 that supports a fourth pinion P4 meshing with both the gears S4 and R4. .

  The transmission input shaft Input is connected to the second ring gear R2 and inputs rotational driving force from at least one of the engine Eng and the motor generator MG. The transmission output shaft Output is connected to the third carrier PC3 and transmits the output rotational driving force to the driving wheels (left and right rear wheels RL, RR) via a final gear or the like.

  The first ring gear R1, the second carrier PC2, and the fourth ring gear R4 are integrally connected by a first connecting member M1. The third ring gear R3 and the fourth carrier PC4 are integrally connected by a second connecting member M2. The first sun gear S1 and the second sun gear S2 are integrally connected by a third connecting member M3.

  The first planetary gear set GS1 includes four rotating elements by connecting the first planetary gear G1 and the second planetary gear G2 with the first connecting member M1 and the third connecting member M3. Is done. Further, the second planetary gear set GS2 is configured to have five rotating elements by connecting the third planetary gear G3 and the fourth planetary gear G4 by the second connecting member M2.

  In the first planetary gear set GS1, torque is input to the second ring gear R2 from the transmission input shaft Input, and the input torque is output to the second planetary gear set GS2 via the first connecting member M1. In the second planetary gear set GS2, torque is directly input to the second connecting member M2 from the transmission input shaft Input, and is also input to the fourth ring gear R4 via the first connecting member M1. Is output from the third carrier PC3 to the transmission output shaft Output.

  The first clutch C1 (input clutch I / C) is a clutch that selectively connects and disconnects the transmission input shaft Input and the second connecting member M2. The second clutch C2 (direct clutch D / C) is a clutch that selectively connects and disconnects the fourth sun gear S4 and the fourth carrier PC4. The third clutch C3 (H & LR clutch H & LR / C) is a clutch that selectively connects and disconnects the third sun gear S3 and the fourth sun gear S4.

  The second one-way clutch F2 is disposed between the third sun gear S3 and the fourth sun gear S4. As a result, when the third clutch C3 is released and the rotational speed of the fourth sun gear S4 is higher than that of the third sun gear S3, the third sun gear S3 and the fourth sun gear S4 generate independent rotational speeds. Therefore, the third planetary gear G3 and the fourth planetary gear G4 are connected via the second connecting member M2, and each planetary gear achieves an independent gear ratio.

  The first brake B1 (front brake Fr / B) is a brake that selectively stops the rotation of the first carrier PC1 with respect to the transmission case Case. The first one-way clutch F1 is disposed in parallel with the first brake B1. The second brake B2 (low brake LOW / B) is a brake that selectively stops the rotation of the third sun gear S3 with respect to the transmission case Case. The third brake B3 (2346 brake 2346 / B) is a brake that selectively stops the rotation of the third connecting member M3 that connects the first sun gear S1 and the second sun gear S2 with respect to the transmission case Case. The fourth brake B4 (reverse brake R / B) is a brake that selectively stops the rotation of the fourth carrier PC3 with respect to the transmission case Case.

  FIG. 6 is a fastening operation table showing a fastening state of each frictional engagement element for each shift stage in the automatic transmission AT mounted on the FR hybrid vehicle to which the control device of the first embodiment is applied. In FIG. 6, ◯ indicates that the friction engagement element is in an engaged state, (◯) indicates that the friction engagement element is in an engagement state at least when the engine brake is operated, and no mark indicates the friction engagement. Indicates that the element is open.

  Of each frictional engagement element provided in the transmission gear mechanism configured as described above, one of the frictional engagement elements that have been engaged is released, and one of the frictional engagement elements that have been released is engaged. By doing so, it is possible to realize a first reverse speed with seven forward speeds as described below.

  That is, in the “first speed”, only the second brake B2 is engaged, and thereby the first one-way clutch F1 and the second one-way clutch F2 are engaged. In “second speed”, the second brake B2 and the third brake B3 are engaged, and the second one-way clutch F2 is engaged. In “third speed”, the second brake B2, the third brake B3, and the second clutch C2 are engaged, and the first one-way clutch F1 and the second one-way clutch F2 are not engaged. In “fourth speed”, the third brake B3, the second clutch C2, and the third clutch C3 are engaged. In "5th gear", the first clutch C1, the second clutch C2, and the third clutch C3 are engaged. In “6th speed”, the third brake B3, the first clutch C1, and the third clutch C3 are engaged. In “7th speed”, the first brake B1, the first clutch C1, and the third clutch C3 are engaged, and the first one-way clutch F1 is engaged. In “reverse speed”, the fourth brake B4, the first brake B1, and the third clutch C3 are engaged.

  Here, as the second clutch CL2 shown in FIG. 1, a friction engagement element that is engaged at each shift speed can be selected. For example, the second brake B2, “1st speed to 3rd speed”, “ The second clutch C2 is used at the "4th speed", the third clutch C3 is used at the "5th speed", and the first clutch C1 is used at the "6th and 7th speed".

  FIG. 7 is a flowchart illustrating a start control process executed by the integrated controller of the first embodiment (start control means). Hereinafter, each step shown in FIG. 7 will be described.

  In step S101, it is determined whether or not a WSC lockup (L / U) command has been output. If YES (with L / U command), the process proceeds to step S102. If NO (without L / U command), Step S101 is repeated. The WSC lockup command is output when the vehicle speed VSP is equal to or higher than the second set vehicle speed VSP2 using the WSC lockup start map shown in FIG. 9 when the travel mode is the WSC mode. Here, the second clutch CL2 that is slip-engaged in the WSC mode is the second brake B2 that achieves the first speed by being engaged.

  In step S102, following the determination in step S101 that there is an L / U command, WSC lockup (L / U) control is started, and the process proceeds to step S103. In this WSC lockup control, the slip engagement state of the second clutch CL2 maintained in the WSC mode is shifted to the lockup engagement, and the clutch transmission torque passing through the second clutch CL2 becomes the output torque of the motor / generator MG. Thus, the torque capacity of the second clutch CL2 is maximized. At this time, an instruction is given to increase the torque capacity of the second clutch CL2 stepwise, and the hydraulic pressure of the second clutch CL2 is increased by a ramp. Note that this step S102 serves as a WSC lockup control unit that locks up the second clutch CL2 from slip engagement.

  In step S103, following the start of WSC lockup control in step S102, the WSC lockup completion time is predicted, and the process proceeds to step S104. The prediction of the WSC lockup completion time is executed based on at least the second clutch differential rotational speed ΔN that is the difference between the input rotational speed NCL2in of the second clutch CL2 and the clutch output rotational speed NCL2out of the second clutch CL2. Here, it is calculated from a table based on accelerator opening APO or driving force (motor / generator MG rotation speed Nm) and second clutch differential rotation speed ΔN after the WSC lockup (L / U) command is output. The timing for completing the lockup engagement of the second clutch CL2 is the timing when the second clutch differential rotation speed ΔN becomes zero. This step S103 serves as a lockup completion time predicting unit that predicts the time until the lockup engagement of the second clutch CL2 is completed.

  In step S104, following the prediction of the WSC lockup completion time in step S103, it is determined whether or not forced lockup (L / U) is required. If YES (forced L / U required), The process proceeds to step S105, and if NO (forced L / U is not required), the process proceeds to step S107. Whether or not forced lockup (L / U) is necessary is determined using the WSC lockup start map shown in FIG. 9 even if the vehicle speed VSP becomes the third set vehicle speed VSP3 or higher. If is not completed, it is judged necessary.

  In step S105, following the determination in step S104 that forced L / U is necessary, complete exclusive lockup (L / U) control is performed, and the flow proceeds to step S106. The complete exclusive lockup control is to realize the first gear by performing lockup engagement of the second clutch CL2 regardless of the presence or absence of an upshift command.

  In step S106, following the complete exclusive L / U control in step S105, it is determined whether or not WSC lockup is completed. If YES (L / U complete), the process proceeds to step S109, and NO (L / If U is not completed), step S105 is repeated. Here, the completion of WSC lockup is determined by whether or not the second clutch differential rotation speed ΔN has become zero. In addition, when this step S105 and step S106 make a forced lockup determination for forcibly engaging the second clutch CL2, the automatic transmission AT is increased after the second clutch CL2 is locked up. This is a complete exclusive control unit that starts shift control.

  In step S107, following the determination that the forced L / U is not required in step S104, it is determined whether an upshift command has been output. If YES (upshift command output), the process proceeds to step S108, and NO ( If no upshift command is output), step S104 is repeated. The upshift command is output when the operating point on the shift map determined by the accelerator opening APO and the vehicle speed VSP crosses the upshift line.

In step S108, following the determination of the upshift command output in step S107, it is determined whether or not the remaining time Δt until lockup completion is less than the upshift response time T , and YES ( remaining time Δt is the response time). If less than T ), the process proceeds to step S109. If NO ( remaining time Δt is equal to or longer than the response time T ), the process returns to step S104. Here, the upshift response time T is a so-called precharge time until the engagement hydraulic pressure of the friction engagement element that realizes the second gear is brought into a state immediately before the start of engagement. Further, the remaining time Δt until completion of lockup is the difference between the WSC lockup completion time predicted in step S103 and the current time.

In step S109, following the determination that the WSC lockup is completed in step S106 or the determination that the remaining time Δt is less than the response time T in step S108, the upshift flag is set and then upshift control is started. Proceed to It should be noted that step S108 and step S109 start the upshift control at a timing earlier than the timing of completion of lockup engagement of the second clutch CL2 by an upshift response time T of the automatic transmission AT. It becomes.

Next, the operation will be described.
The operation of the electric vehicle control apparatus according to the first embodiment will be described by dividing it into “normal WSC lockup control operation” and “forced WSC lockup control operation”.

[Normal WSC lockup control action]
Fig. 8 shows the normal WSC lockup control action when shifting up from the WSC mode to the 1st-2 speed. Accelerator opening, CL2 torque capacity, 1-2UP flag, AT output speed, WSC, L / U command oil pressure・ It is a time chart showing each characteristic of 1-2UP command oil pressure.

  If a WSC lockup command is output at time t1 while the vehicle is started and traveling in the WSC mode, the process proceeds from step S101 to step S102 in the flowchart shown in FIG. 7, and WSC lockup control is started. As a result, an instruction to increase the torque capacity of the second clutch CL2 is issued in steps, and the WSC and L / U command hydraulic pressures, which are command hydraulic pressures of the second clutch CL2, are increased by ramps. As a result, the differential rotational speed between the AT output rotational speed and the first speed target rotational speed gradually decreases. The first speed target rotational speed is a target value of the AT output rotational speed when the first speed stage is realized. At this time, the accelerator opening is constant.

  Then, the process proceeds from step S102 to step S103, and the WSC lockup completion time is predicted. Here, the WSC lockup control is a control for gradually decreasing the second clutch differential rotation speed ΔN generated by maintaining the second clutch CL2 in the slip engagement state in the WSC mode, and starts at time ta in FIG. The performed WSC lockup control is completed at time tb. At this time, the length between the time ta and the time tb is determined by the gradient of the second clutch output rotational speed NCL2out with respect to the second clutch input rotational speed NCL2in, that is, at least the second clutch differential rotational speed ΔN. It is calculated from a table based on the degree APO or the driving force (the rotational speed Nm of the motor / generator MG) and the second clutch differential rotational speed ΔN. That is, the WSC lockup completion time is predicted based on at least the differential rotational speed ΔN of the second clutch CL2, and here, the accelerator opening APO or the driving force (the rotational speed Nm of the motor / generator MG) and the second This is executed using the differential rotation speed ΔN of the clutch CL2 as a parameter. Thereby, more accurate time prediction can be performed.

  Then, when the rotational speed difference ΔN of the second clutch CL2 gradually decreases and the vehicle speed VSP increases and an upshift command is output at time t2, in the flowchart shown in FIG. 7, from step S104 to step S107 to step S108. The remaining time Δt until completion of lockup engagement is compared with the upshift response time T.

  At time t3, when the remaining time Δt until completion of the lockup is less than the upshift response time T, that is, when the YES condition in step S108 is satisfied, the upshift flag (1-2UP flag) is set and the second speed is set. The hydraulic pressure (1-2UP command hydraulic pressure) of the friction engagement element of the automatic transmission AT that realizes the stage is set to the precharge pressure. At this time, the second clutch CL2 is not locked up, and a differential rotation occurs between the AT output rotation speed and the first speed target rotation speed.

  Thereafter, at time t4, when the differential rotational speed ΔN of the second clutch CL2 becomes zero, that is, when the AT output rotational speed and the first speed target rotational speed match, the second clutch CL2 torque capacity becomes maximum and the second WSC, L / U command oil pressure, which is the oil pressure of the clutch CL2, becomes the line pressure. At this time, since the hydraulic pressure (1-2UP command hydraulic pressure) of the frictional engagement element of the automatic transmission AT realizing the second speed has reached the precharge pressure, it is possible to shift to the torque phase without wasting time.

  That is, the upshift control of the automatic transmission AT is started at a timing (time t3) that is earlier than the timing of completion of lockup engagement of the second clutch CL2 (time t4) by the upshift response time T of the automatic transmission AT. As a result, the WSC lockup control and the upshift control are not completely exclusive, and the control time from the slip engagement state of the second clutch CL2 to the lockup engagement and the subsequent start of the upshift is saved without wasting time. Shortening can be achieved.

[Forced WSC lockup control action]
When the vehicle is started and the vehicle is traveling in the WSC mode, a WSC lockup command is output. In the flowchart shown in FIG. 7, the process proceeds from step S101 to step S102, and after starting WSC lockup control, step S103 → step Proceeding to S104, the WSC lockup completion time is predicted, and the necessity of forced lockup (L / U) is determined.

  Then, using the WSC lockup start map shown in FIG. 9, if the WSC lockup is not completed even if the vehicle speed VSP is equal to or higher than the third set vehicle speed VSP3, it is determined that the forced lockup is necessary, and the process proceeds to step S105. Proceed with full exclusive lockup (L / U) control. That is, the first gear is realized by performing the lock-up engagement of the second clutch CL2 regardless of the presence or absence of the upshift command.

  Then, the process proceeds to step S106, and if it can be determined that the WSC lockup is completed, that is, if the second clutch differential rotation speed ΔN becomes zero, the process proceeds to step S109, and the upshift control is executed.

  As described above, when the forced lockup determination for forcibly engaging the second clutch CL2 is made, the upshift control of the automatic transmission AT is started after the second clutch CL2 is engaged for the lockup. That is, when the vehicle speed VSP becomes equal to or higher than the third set vehicle speed VSP3 in the WSC lockup start map, the upshift control is started after a predetermined time from this point.

  As a result, when the forced lockup determination is made, the WSC lockup control and the shiftup control are in a completely exclusive relationship, and even if the completion time of the WSC lockup control exceeds the estimated time, the WSC lockup control is performed. Interference between up-control and up-shift control can be prevented.

Next, the effect will be described.
In the control apparatus for an electric vehicle according to the first embodiment, the following effects can be obtained.

  (1) A transmission (automatic transmission) AT that is arranged downstream of a drive source having a motor (motor / generator) MG and achieves a plurality of shift speeds by changing friction engagement elements, and the drive source when starting The WSC running control is executed to maintain the slip engagement state of the clutch (second clutch) CL2 interposed between the driving wheel (left and right rear wheels) RL and RR and control the clutch torque capacity of the clutch CL2. And a start control means (FIG. 7), wherein the start control means executes WSC lockup control for shifting the clutch CL2 from slip engagement to lockup engagement. Unit (step S102), a lockup completion time prediction unit (step S103) for predicting a time until lockup engagement completion of the clutch CL2, and the lockup Upshift control of the transmission AT is started at a timing that is earlier by the upshift response time T of the transmission AT than the timing of completion of lockup engagement of the clutch CL2 predicted by the end time prediction unit (step S103). And a carry-up upshift control unit (steps S108 and S109). For this reason, it is possible to shorten the control time from the slip engagement state of the clutch CL2 at the start to the lock-up engagement and the subsequent start of the upshift.

  (2) The lockup completion prediction unit (step S103) is configured to predict the time until the clutch lockup engagement is completed based on at least the differential rotation speed ΔN of the clutch CL2. For this reason, prediction time can be grasped | ascertained correctly.

  (3) The lockup completion prediction unit (step S103) performs the process until the lockup engagement is completed using the accelerator opening APO or the driving force (motor / generator MG rotation speed Nm) and the differential rotation speed ΔN of the clutch CL2 as parameters. It was set as the structure which estimates this time. For this reason, the prediction time can be calculated accurately and easily.

  (4) When the start control means (FIG. 7) determines that the clutch CL2 is forcibly locked up, the transmission control means (FIG. 7) raises the transmission AT after the clutch CL2 is locked up. A complete exclusive control unit (steps S105 and S106) for starting shift control is employed. For this reason, even when the WSC lockup control time of the clutch CL2 becomes longer than expected, interference between the WSC lockup control and the shift up control can be prevented.

  As mentioned above, although the control apparatus of the electric vehicle of this invention has been demonstrated based on Example 1, it is not restricted to these Examples about a concrete structure, The invention which concerns on each claim of a claim Design changes and additions are permitted without departing from the gist of the present invention.

  In the first embodiment, the timing of completion of the lockup engagement in the lockup completion prediction unit (step S103) is set when the differential rotation speed ΔN of the second clutch CL2 becomes zero. This differential rotation speed ΔN is determined in advance. The timing when the set value or less is reached may be the completion of lock-up engagement. Thereby, the control time can be further shortened.

  In the first embodiment, the electric vehicle control device of the present invention is applied to the FR hybrid vehicle. However, the drive source includes only the motor or only the motor / generator as well as the FF hybrid vehicle. It can also be applied to electric vehicles such as electric vehicles and fuel cell vehicles. In short, a stepped automatic transmission is installed at the downstream position of the drive source having a motor, and a clutch is interposed between the drive source and the drive wheel, and the clutch torque capacity is controlled by slipping the clutch when starting. Any electric vehicle can be applied.

MG motor / generator (motor)
Eng engine
AT automatic transmission
CL2 Second clutch (clutch)
RL, RR Left and right rear wheels (drive wheels)

Claims (5)

A transmission that is arranged downstream of a drive source having a motor and achieves a plurality of shift speeds by switching frictional engagement elements, and a slip of a clutch that is interposed between the drive source and drive wheels when starting In a control device for an electric vehicle, comprising: a start control means for performing WSC travel control for maintaining the engaged state and controlling the clutch torque capacity of the clutch;
The start control means includes a WSC lockup control unit that performs WSC lockup control for shifting the clutch from slip engagement to lockup engagement during the WSC travel control ;
A lockup completion time prediction unit for predicting a time until the clutch lockup engagement is completed;
When an upshift command for the transmission is output during the WSC lockup control, the lock is a difference between the time until completion of lockup engagement of the clutch predicted by the lockup completion time prediction unit and the current time. When the remaining time until completion of up is less than the upshift response time of the transmission, the upshift control unit that starts upshift control of the transmission without waiting for completion of the lockup engagement ,
A control device for an electric vehicle characterized by comprising: In the control device of the electric vehicle according to claim 1,
The control apparatus for an electric vehicle, wherein the lockup completion prediction unit predicts a time until lockup engagement completion of the clutch based on at least the differential rotation speed of the clutch. In the control apparatus of the electric vehicle according to claim 2,
The lockup completion prediction unit predicts the time until lockup engagement is completed using the accelerator opening or driving force and the differential rotational speed of the clutch as parameters. In the control apparatus of the electric vehicle according to claim 2,
The control device for an electric vehicle, wherein the lockup completion prediction unit sets a timing at which the differential rotation speed of the clutch becomes equal to or less than a set value as a timing of completion of lockup engagement of the clutch. In the control apparatus of the electric vehicle as described in any one of Claims 1-4,
The start control means, when a forced lockup determination for forcibly locking up the clutch is made, a complete exclusive control unit that starts upshift control of the transmission after the clutch is locked up An electric vehicle control device comprising:

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