JP2010164124A - Controller for electric vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a controller for an electric vehicle capable of securing power transmission from a drive source by increasing the temperature of hydraulic oil of an automatic transmission more preferentially than a battery. <P>SOLUTION: The controller for the electric vehicle includes the automatic transmission AT, which is arranged at the downstream position of the drive source having a motor (motor/generator) MG and achieves a plurality of gear shift stages by changing the engagement of friction fastening elements, and a gear shift control means (Fig.6), which disengages and engages the friction fastening elements by a hydraulic pressure when a gear is shifted. In this controller, the gear shift control means has a first cold-machine gear shift control portion (Step S107, Fig.7 (not shown)). This first cold-machine gear shift control portion performs hydraulic pressure reduction inertia phase control that extends a slip fastening time by reducing the fastening hydraulic pressure of the friction fastening elements of the automatic transmission AT when gear shift takes place in the first cold machine period in a state that the hydraulic oil of the automatic transmission AT and the battery 4 are in a cold machine state. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention is a control device for an electric vehicle that executes shift control for achieving a plurality of shift stages by changing friction engagement elements of an automatic transmission with hydraulic pressure.

  2. Description of the Related Art There is known a control device for an electric vehicle that achieves a plurality of shift stages by hydraulically switching friction engagement elements of an automatic transmission disposed at a downstream position of a drive source having a motor (see, for example, Patent Document 1).

JP 2007-261498

  However, in the conventional control device for an electric vehicle, the engagement hydraulic pressure of the friction engagement element is constant during the shift regardless of the state of the hydraulic oil of the automatic transmission and the state of the battery that supplies power to the motor. For this reason, there is a problem that it takes time to transmit power from the drive source in a cold state where the temperature rise rate of the hydraulic oil is slow and the hydraulic oil temperature is low.

  The present invention has been made paying attention to the above problem, and provides an electric vehicle control device capable of preferentially raising the temperature of hydraulic oil of an automatic transmission over a battery and ensuring power transmission from a drive source. The purpose is to provide.

  In order to achieve the above object, in the present invention, an automatic transmission that is arranged at a downstream position of a drive source having a motor and achieves a plurality of shift speeds by changing friction engagement elements, and at the time of shifting, the friction engagement elements are hydraulically operated. In the control device for an electric vehicle, the shift control unit has a first cold-time shift control unit. This first cold-time speed change control unit lowers the engagement hydraulic pressure of the friction engagement element of the automatic transmission when the first oil-cooling operation is performed when the hydraulic oil and battery of the automatic transmission are in the cold state, and the slip engagement is performed. The oil pressure lowering inertia phase control to increase the time is executed.

  Therefore, in the control apparatus for an electric vehicle according to the present invention, when the hydraulic oil and the battery are both in the cold state, the hydraulic pressure of the frictional engagement element of the automatic transmission is lowered to increase the slip engagement time. Thus, it is possible to preferentially raise the temperature of the hydraulic oil over the battery, and to secure power transmission from the drive source.

1 is an overall system diagram showing an FR hybrid vehicle (an example of a vehicle) by rear wheel drive to which a control device for an electric vehicle according to a first embodiment 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. 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 shift control process executed by the integrated controller according to the first embodiment. It is a flowchart which shows the flow of the 1st cold time shift control process in the shift control process performed with the integrated controller of Example 1. FIG. It is a flowchart which shows the flow of the 2nd cold time shift control process in the shift control process performed with the integrated controller of Example 1. FIG. It is a time chart which shows each characteristic of command oil pressure, input number of rotations, and MG torque explaining the 1st cold time shift control action in auto upshift which is an example of a shift pattern. It is a time chart which shows each characteristic of command oil pressure, input number of rotations, and MG torque explaining the 2nd cold time shift control action in auto upshift which is an example of a shift pattern. 6 is a flowchart showing a flow of a shift control process executed by the integrated controller of the second embodiment. It is a flowchart which shows the flow of the 1st cold time shift control process in the shift control process performed with the integrated controller of Example 2. FIG. It is a flowchart which shows the flow of the 2nd cold time shift control process in the shift control process performed with the integrated controller of Example 2. 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 and Example 2 which are shown in drawing.

First, the configuration will be described.
FIG. 1 is an overall system diagram showing a rear-wheel drive FR hybrid vehicle to which an electric vehicle control apparatus according to a 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 of the motor assist travel mode, travel power generation mode, and engine travel mode. The “WSC mode” is controlled by the rotation speed control of the motor / generator MG at the time of P / N → D select start from the “HEV mode” or the D range start from the “EV mode” or “HEV mode”. In this mode, the clutch clutch torque capacity is controlled so that the clutch transmission torque that passes through the second clutch CL2 is the required drive torque that is determined according to the vehicle condition and driver operation. is there. “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.

  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. Hereinafter, the arithmetic processing executed by the integrated controller 10 according to the first embodiment will be described with reference to FIGS.

  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. When the P, N → D select starts from the “HEV mode”, the “WSC mode” is selected as the target travel mode until the vehicle speed VSP reaches a predetermined vehicle speed.

  The target charge / discharge calculation unit 300 calculates a target charge / discharge power tP from the battery SOC using a predetermined target charge / discharge amount map.

  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. 4 is a skeleton diagram illustrating an example of an automatic transmission mounted on an FR hybrid vehicle to which the control device for an electric vehicle according to 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 a transmission input shaft Input. The rotation speed is changed by one planetary gear and the seven frictional engagement elements, and is output from the transmission output shaft Output. Next, a transmission gear mechanism (transmission 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 a driving source for driving (engine Eng and 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 PC4 with respect to the transmission case Case.

  FIG. 5 is a fastening operation table showing a fastening state of each frictional engagement element for each shift stage in the automatic transmission mounted on the FR hybrid vehicle to which the control device for the electric vehicle according to the first embodiment is applied. In FIG. 5, a circle indicates that the friction engagement element is in an engaged state, a circle (◯) indicates that the friction engagement element is in an engagement state at least during engine brake operation, 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. 6 is a flowchart showing the flow of a shift control process executed by the integrated controller of the first embodiment (shift control means). Hereinafter, each step shown in FIG. 6 will be described.

In step S101, it is determined whether or not a shift command has been issued. If YES (there is a shift command), the process proceeds to step S102, and if NO (no shift command), the step S101 is repeated.
The shift command is output when the driving point on the shift map determined by the accelerator opening APO and the vehicle speed VSP crosses the upshift line or the downshift line when driving with the D range selected. When crossing the upshift line, an upshift command is output, and when crossing the downshift line, a downshift command is output.

  In step S102, following the determination that there is a shift command in step S101, the battery temperature detection value of the battery temperature sensor 23, that is, the battery temperature B_t is read, and the process proceeds to step S103. The read battery temperature B_t is stored in the integrated controller 10.

  In step S103, following the reading of the battery temperature B_t in step S102, the oil temperature detection value of the oil temperature sensor 22, that is, the ATF temperature ATF_t is read, and the process proceeds to step S104. The read ATF temperature ATF_t is stored in the integrated controller 10.

In step S104, following the reading of the ATF temperature ATF_t in step S103, it is determined whether or not the battery temperature B_t is less than a preset set value B_t ₀ , in other words, whether or not the battery 4 is in a cold state. If NO (more than the set value), the process proceeds to step S105. If YES (less than the set value), the process proceeds to step S106. This step S104 serves as a battery determination means for determining the state of the battery 4.

  In step S105, following the determination that the battery temperature B_t is equal to or higher than the set value in step S104, normal shift control is performed, and the process proceeds to return.

In step S106, following the determination that the battery temperature B_t is less than the set value in step S104, whether or not the ATF temperature ATF_t is less than the preset set value ATF_t ₀ , in other words, the hydraulic oil of the automatic transmission AT is in the cold state. If YES (less than the set value), the process proceeds to step S107. If NO (not less than the set value), the process proceeds to step S108. Note that this step S106 serves as hydraulic oil determination means for determining the hydraulic oil state of the automatic transmission AT. Here, the hydraulic oil state is determined based on the detection value of the oil temperature sensor 22 that detects the ATF temperature ATF_t.

  In step S107, following the determination that the ATF temperature ATF_t is less than the set value in step S106, the first cold-time shift control is performed assuming that the hydraulic oil and the battery 4 are both in the cold state, and the process proceeds to return. . Note that step S107 is a first cool-down speed shift control unit that executes hydraulic pressure lowering inertia phase control that lowers the engagement hydraulic pressure of the friction engagement element and increases the slip engagement time of the friction engagement element during the first cold operation. .

  In step S108, following the determination that the ATF temperature ATF_t is equal to or higher than the set value in step S106, the second cold speed shift control is performed assuming that the hydraulic oil is in a warm air state and the battery 4 is in a cold state. Proceed to return. In addition, this step S108 is a 2nd cooling time transmission control part which performs the hydraulic pressure raise inertia phase control which makes the fastening hydraulic pressure of a friction engagement element high at the time of 2nd cooling.

  FIG. 7 is a flowchart showing the flow of the first cold-time shift control process in step S107 (first cold-time shift control unit).

  In step S71, standby phase (pre-processing) control is performed, and the process proceeds to step S72. In this standby phase control, a hydraulic pressure command for setting the engagement hydraulic pressure of the engagement side frictional engagement element to the standby pressure (pressure at which the piston enters a stroke state) is output from the AT controller 7 to the second clutch hydraulic unit 8.

  In step S72, following execution of the standby phase control in step S71, it is determined whether or not this standby phase control has ended. If YES (finished), the process proceeds to step S73, and NO (not finished) ), The process returns to step S71. Here, the end of the standby phase control is determined by whether or not the engagement hydraulic pressure of the engagement side frictional engagement element is equal to or higher than the standby pressure.

  In step S73, following the determination of the end of the standby phase control in step S72, torque phase control is performed, and the process proceeds to step S74. In this torque phase control, a hydraulic pressure command for increasing the engagement hydraulic pressure with a predetermined gradient is output from the AT controller 7 to the second clutch hydraulic unit 8.

  In step S74, following execution of the torque phase control in step S73, it is determined whether or not the transmission input rotational speed is changing, in other words, whether or not the torque phase has shifted to the inertia phase, and YES ( If the rotation is changing), the process proceeds to step S75. If NO (not changing the rotation), the process returns to step S73. The transmission input rotation speed may be calculated from the detection value of the resolver 13, or a shaft rotation sensor that detects the rotation speed of the transmission input shaft Input of the automatic transmission AT is provided. The detection value may be read.

  In step S75, following the determination that the rotation is changing in step S74, the hydraulic pressure reduction inertia phase control is performed, and the process proceeds to step S76. In this oil pressure lowering inertia phase control, the engagement hydraulic pressure is lower than the engagement hydraulic pressure of the engagement side frictional engagement element (hereinafter referred to as normal hydraulic pressure) during inertia phase control (hereinafter referred to as normal inertia phase control) in normal shift control. Then, a hydraulic pressure command for increasing the sliding engagement time of the engagement side frictional engagement element is output from the AT controller 7 to the second clutch hydraulic unit 8.

  In step S76, following execution of the oil pressure lowering inertia phase control in step S75, MG torque cut control is performed, and the process proceeds to step S77. In this MG torque cut control, the torque of the motor / generator MG (hereinafter referred to as MG torque) is reduced, that is, a target MG torque instruction for torque cut is output to the motor controller 2. Since the battery 4 is in the cold state in the first cold-time shift control, the MG torque limit (the range of MG torque that can be torque-cut) is the MG torque cut that is executed during the normal shift control in which the battery 4 is in the warm-up state. It is more limited than the MG torque limit in the control.

  In step S77, following execution of MG torque cut control in step S76, is a rotation synchronization determination condition (= condition in which the gear ratio has completely shifted to the post-shift gear ratio) established to eliminate the differential rotation of the engagement side frictional engagement element? If YES (rotation synchronization determination condition is satisfied), the process proceeds to step S78. If NO (rotation synchronization determination condition is not satisfied), the process returns to step S75.

  In step S78, following the determination that the rotation synchronization determination condition is satisfied in step S77, the engagement side frictional engagement element is shifted to the complete engagement state, the shift end phase (post-processing) control is performed, and the process proceeds to the end. At this time, the open side frictional engagement element shifts to a fully open state.

  FIG. 8 is a flowchart showing the flow of the second cold-time shift control process in step S108 (second cold-time shift control unit).

  In step S81, standby phase (pre-processing) control is performed, and the process proceeds to step S82. In this standby phase control, a hydraulic pressure command for setting the engagement hydraulic pressure of the engagement side frictional engagement element to the standby pressure (pressure at which the piston enters a stroke state) is output from the AT controller 7 to the second clutch hydraulic unit 8.

  In step S82, following execution of the standby phase control in step S81, it is determined whether or not this standby phase control has ended. If YES (finished), the process proceeds to step S83, and NO (not finished) ), The process returns to step S81. Here, the end of the standby phase control is determined by whether or not the engagement hydraulic pressure of the engagement side frictional engagement element is equal to or higher than the standby pressure.

  In step S83, following the determination of the end of standby phase control in step S82, torque phase control is performed, and the flow proceeds to step S84. In this torque phase control, a hydraulic pressure command for increasing the engagement hydraulic pressure with a predetermined gradient is output from the AT controller 7 to the second clutch hydraulic unit 8.

  In step S84, following execution of the torque phase control in step S83, it is determined whether or not the transmission input rotational speed is changing, in other words, whether or not the torque phase has shifted to the inertia phase, and YES ( If the rotation is changing), the process proceeds to step S85. If NO (not changing the rotation), the process returns to step S83.

  In step S85, following the determination that the rotation is changing in step S84, the hydraulic pressure increase inertia phase control is performed, and the process proceeds to step S86. In this hydraulic pressure increase inertia phase control, a hydraulic pressure command for increasing the engagement hydraulic pressure is output from the AT controller 7 to the second clutch hydraulic unit 8 than the normal hydraulic pressure during the normal inertia phase control.

  In step S86, following execution of the hydraulic pressure increase inertia phase control in step S85, MG torque cut control is performed, and the process proceeds to step S87. In this MG torque cut control, the torque of the motor / generator MG (hereinafter referred to as MG torque) is reduced, that is, a target MG torque instruction for torque cut is output to the motor controller 2. Since the battery 4 is in the cold state in the second cold-time shift control, the MG torque limit (the range of MG torque that can be torque-cut) is the MG torque cut that is executed during the normal shift control in which the battery 4 is in the warm-up state. It is more limited than the MG torque limit in the control.

  In step S87, following execution of the MG torque cut control in step S86, is a rotation synchronization determination condition (= condition in which the gear ratio has completely shifted to the post-shift gear ratio) established to eliminate the differential rotation of the engagement side frictional engagement element? If YES (rotation synchronization determination condition is satisfied), the process proceeds to step S88. If NO (rotation synchronization determination condition is not satisfied), the process returns to step S85.

  In step S88, following the determination that the rotation synchronization determination condition is satisfied in step S87, the engagement side frictional engagement element is shifted to the complete engagement state, the shift end phase (post-processing) control is performed, and the process proceeds to the end. At this time, the open side frictional engagement element shifts to a fully open state.

Next, the operation will be described.
The operation of the control device for the FR hybrid vehicle of the first embodiment will be described by dividing it into “first cold speed shift control action” and “second cold speed shift control action”.

[Shift control action during first cold machine]
FIG. 9 is a time chart showing the characteristics of the command hydraulic pressure, the input rotation speed, and the MG torque for explaining the first cold-time shift control operation in the auto upshift that is an example of the shift pattern. In addition, each characteristic at the time of normal speed change control is shown by the dashed-dotted line in a figure.

  When a shift command is output at time t1, in the flowchart shown in FIG. 6, the process proceeds from step S101 to step S104 to step S103 to step S104, and the state determination of the battery 4 is executed. If the battery 4 is in the cold state, Proceeding to step S106, the state determination of the hydraulic oil of the automatic transmission AT is performed. If the hydraulic oil is in the cold state, the process proceeds to step S107 and the first cold-time shift control is executed. That is, the first cold-time shift control is executed when both the hydraulic oil of the automatic transmission AT and the battery 4 are in the cold state.

  At this time, the oil temperature sensor 22 that detects the ATF temperature ATF_t of the automatic transmission AT is provided, and the state of the hydraulic oil is determined based on the detection value of the oil temperature sensor 22 in step S106. Therefore, it is possible to accurately determine the speed change control according to the state of the hydraulic oil.

  When the first cold-time shift control is executed, the standby phase control in step S71 (see FIG. 7) is executed until time t2. Thus, in the standby phase from time t1 to time t2, the engagement hydraulic pressure of the engagement side frictional engagement element in the automatic transmission AT is controlled to be the standby pressure. At this time, neither the transmission input speed nor the MG torque changes.

  When the engagement hydraulic pressure reaches the standby pressure and shifts from the standby phase to the torque phase, torque phase control in step S73 (see FIG. 7) is executed. Thus, in the torque phase from time t2 to time t3, the fastening hydraulic pressure is controlled to increase with a predetermined gradient. At this time, neither the transmission input speed nor the MG torque changes.

  Then, when the transmission input rotational speed is changed to shift from the torque phase to the inertia phase, the process proceeds from step S75 to step S76 (see FIG. 7), and hydraulic pressure lowering inertia phase control and MG torque cut control are executed.

  Thereby, in the inertia phase until the rotation synchronization determination from time t3 to time t4 is made, the engagement hydraulic pressure is controlled to be lower than the normal engagement hydraulic pressure at the time of the normal inertia phase control indicated by the one-dot chain line, and at the same time, The MG torque is controlled to be small.

  Therefore, when the engagement hydraulic pressure is lower than the normal engagement hydraulic pressure, the sliding engagement time of the engagement side frictional engagement element is longer than that during the normal inertia phase control, and the heat generation amount of the engagement side frictional engagement element is increased compared with the normal time. The temperature ATF_t can be preferentially raised over the battery temperature B_t. As a result, the driving force of the engine Eng or the motor / generator MG as a driving source can be transmitted to the left rear wheel RL and the right rear wheel RR as driving wheels, and the traveling of the vehicle can be ensured.

  Further, the shift time can be shortened by reducing the MG torque. Here, since the engagement hydraulic pressure is lower than that in the normal shift control, the change time of the transmission input rotation speed becomes longer than that in the normal inertia phase control, and the change speed of the input rotation speed becomes slow. That is, the change rate of the input rotation speed is reduced. On the other hand, since the MG torque is obtained by the product of the inertia torque of the motor / generator MG and the change rate of the transmission input rotation speed, the required MG torque is reduced by increasing the change time of the transmission input rotation speed.

  Since the battery 4 is in the cold state at the time of the first cold shift control, the torque limit is limited when the MG torque cut control is executed, and the same torque cut as the MG torque cut control at the normal inertia phase control is performed. I can't. However, as described above, the required MG torque is reduced, and it is possible to cope with torque limit limitation.

  When the change in the input rotational speed of the automatic transmission AT stops, a rotation synchronization determination is performed (time t4 to time t5), and when the rotation synchronization determination condition is satisfied, the shift end phase control in step S78 (see FIG. 7) is executed. Is done. Thus, in the shift end phase from time t5 to time t6, the engagement hydraulic pressure of the engagement side frictional engagement element is controlled to be the line pressure. At this time, the transmission input rotational speed is stabilized at the post-shift input rotational speed, and the MG torque is controlled to be equal to that before the shift.

[2nd cold speed shift control action]
FIG. 10 is a time chart showing the characteristics of the command hydraulic pressure, the input rotation speed, and the MG torque for explaining the second cold-time shift control operation in the auto upshift as an example of the shift pattern. In addition, each characteristic at the time of normal speed change control is shown by the dashed-dotted line in a figure.

  When the shift command is output at time t7, in the flowchart shown in FIG. 6, the process proceeds from step S101 to step S104 to step S103 to step S104, the state determination of the battery 4 is executed, and if the battery 4 is in the cold state. Proceeding to step S106, the state determination of the hydraulic oil of the automatic transmission AT is performed. Then, if the hydraulic oil is in a warm-up state, the process proceeds to step S108, and the second cold-time shift control is executed. That is, when the hydraulic oil of the automatic transmission AT is in the warm-up state and the battery 4 is in the cold state, the second cold-time shift control is executed.

  When the second cold-time shift control is executed, the standby phase control in step S81 (see FIG. 8) is executed until time t8. Thus, in the standby phase from time t7 to time t8, the engagement hydraulic pressure of the engagement side frictional engagement element in the automatic transmission AT is controlled to be the standby pressure. At this time, neither the transmission input speed nor the MG torque changes.

  When the engagement hydraulic pressure reaches the standby pressure and shifts from the standby phase to the torque phase, torque phase control in step S83 (see FIG. 8) is executed. Thereby, in the torque phase from time t8 to time t9, the fastening hydraulic pressure is controlled to increase with a predetermined gradient. At this time, neither the transmission input speed nor the MG torque changes.

  Then, when the transmission input rotational speed is changed to shift from the torque phase to the inertia phase, the process proceeds from step S85 to step S86 (see FIG. 8), and the hydraulic pressure increase inertia phase control and MG torque cut control are executed.

  Thereby, in the inertia phase until the rotation synchronization determination from time t9 to time t10 is made, the engagement hydraulic pressure is controlled to be higher than the normal engagement hydraulic pressure at the time of the normal inertia phase control indicated by the one-dot chain line, and the transmission The input rotation speed gradually decreases. Also, the MG torque is controlled to be small.

  At this time, since the battery 4 is in the cold state, the torque limit is limited when the MG torque cut control is executed, and the same torque cut as the MG torque cut control during the normal inertia phase control cannot be performed. However, by increasing the engagement hydraulic pressure of the engagement side frictional engagement element, the torque cut shortage of the MG torque can be compensated by the clutch transmission torque, and the target transmission input rotational speed can be set at the same speed as that during normal inertia phase control. Can be changed.

  As a result, even in the second cold-time shift control in which sufficient MG torque cut cannot be performed due to the torque limit limitation, the shift can be advanced with a response comparable to that of the normal shift control.

  When the change in the input rotational speed of the automatic transmission AT stops, rotation synchronization determination is performed (time t10 to time t11), and when the rotation synchronization determination condition is satisfied, the shift end phase control in step S88 (see FIG. 8) is executed. Is done. Thus, in the shift end phase from time t11 to time t12, the engagement hydraulic pressure of the engagement side frictional engagement element is controlled to be the line pressure. At this time, the transmission input rotational speed is stabilized at the post-shift input rotational speed, and the MG torque is controlled to be equal to that before the shift.

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) An 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 switching friction engagement elements, and the friction engagement elements are connected and disconnected at the time of shifting. In the control apparatus for an electric vehicle provided with a shift control means (FIG. 6), hydraulic oil determination means (step S106) for determining the state of the hydraulic oil of the automatic transmission AT, and a battery 4 for supplying power to the motor MG Battery determination means (step S104) for determining the state of the above, the shift control means (FIG. 6), the first hydraulic when the hydraulic oil is in the cold state, and the battery 4 is in the cold state, A first cold-time shift control unit (step S107, FIG. 7) that executes hydraulic pressure lowering inertia phase control that lowers the engagement hydraulic pressure of the friction engagement element and increases the sliding engagement time of the friction engagement element. It was formed. For this reason, the operating oil of the automatic transmission AT can be preferentially heated over the battery 4 to ensure power transmission from the drive source.

  (2) The shift control means (FIG. 6) increases the hydraulic pressure that increases the engagement hydraulic pressure of the frictional engagement element when the hydraulic oil is in a warm-up state and the battery 4 is in the cold-down state. The second cooler shift control unit (step S108, FIG. 8) that executes inertia phase control is employed. For this reason, the shortage of torque cut caused by the torque limit limitation due to the cold state of the battery 4 can be compensated by the clutch transmission torque, and the shift can proceed with the same level of response as the normal shift control.

  (3) The shift control means (FIG. 6) includes a motor torque cut control unit (steps S76 and S86) that reduces torque (MG torque) from the motor MG when downshifting. For this reason, the shift time can be shortened.

  (4) It has an oil temperature detecting means (oil temperature sensor) 22 for detecting the operating oil temperature (ATF temperature ATF_t) of the automatic transmission AT, and the operating oil determining means (step S106) Based on this, the state of the hydraulic oil is determined. For this reason, it is possible to accurately determine the hydraulic oil state, and it is possible to perform appropriate shift control according to the state of the hydraulic oil.

  In the second embodiment, the state of the hydraulic oil is determined based on the standby phase time at the time of shifting.

First, the configuration will be described.
FIG. 11 is a flowchart illustrating the flow of a shift control process according to the second embodiment (shift control unit). Hereinafter, each step shown in FIG. 11 will be described.

  In step S201, it is determined whether or not a shift command has been issued. If YES (there is a shift command), the process proceeds to step S102, and if NO (no shift command), the step S201 is repeated.

  In step S202, following the determination that there is a shift command in step S201, the battery temperature detection value of the battery temperature sensor 23, that is, the battery temperature B_t is read, and the process proceeds to step S203. The read battery temperature B_t is stored in the integrated controller 10.

In step S203, following the reading of the battery temperature B_t in step S202, it is determined whether or not the battery temperature B_t is less than a preset set value B_t ₀ , in other words, whether or not the battery 4 is in a cold state. If NO (more than the set value), the process proceeds to step S204. If YES (less than the set value), the process proceeds to step S205. This step S203 serves as a battery determination means for determining the state of the battery 4.

  In step S204, following the determination that the battery temperature B_t is equal to or higher than the set value in step S203, normal shift control is performed, and the process proceeds to return.

  In step S205, following determination that the battery temperature B_t is less than the set value in step S203, standby phase (pre-processing) control is performed, and the process proceeds to step S206.

  In step S206, following execution of the standby phase control in step S205, it is determined whether or not this standby phase control has ended. If NO (during control), the process proceeds to step S207, and if YES (completed) Then, the process proceeds to step S208.

  In step S207, the standby time T is counted following the determination that the standby phase control is being performed in step S206. The count of the standby time T is obtained by setting the timing for starting execution of the standby phase control to zero and adding the time α until the control end determination is added thereto.

In step S208, following the determination of the end of the standby phase in step S206, whether or not the counted standby time T is less than the preset set value T ₀ , in other words, the hydraulic oil of the automatic transmission AT is set to the set time. In a state where standby phase control cannot be executed, that is, whether or not the hydraulic oil is in a cold state, the process proceeds to step S209 if YES (less than the set value), and step if NO (set value or more). Proceed to S210. Note that this step S208 serves as hydraulic oil determination means for determining the hydraulic oil state of the automatic transmission AT. Here, the hydraulic oil state is determined based on the length of the standby control time T of the engagement hydraulic pressure.

  In step S209, following the determination that the standby time T is less than the set value in step S208, the first cold-time speed change control is performed assuming that the hydraulic oil and the battery 4 are both in the cold state, and the process proceeds to return. . Note that step S209 is a first cool-down speed shift control unit that executes hydraulic pressure lowering inertia phase control that lowers the engagement hydraulic pressure of the friction engagement element and increases the slip engagement time of the friction engagement element during the first cold operation. .

  In step S210, following the determination that the standby time T is equal to or greater than the set value in step S208, the second cold-time shift control is performed assuming that the hydraulic oil is in the warm-up state and the battery 4 is in the cold-down state. Proceed to return. In addition, this step S210 is a second cold-time shift control unit that executes hydraulic pressure increase inertia phase control for increasing the engagement hydraulic pressure of the friction engagement element at the second cold time.

  FIG. 12 is a flowchart showing the flow of the first cold-time shift control process (first cold-time shift control unit) in step S209.

  In step S91, torque phase control is performed, and the process proceeds to step S92.

  In step S92, following execution of torque phase control in step S91, it is determined whether or not the transmission input rotational speed is changing, in other words, whether or not the torque phase has shifted to the inertia phase, and YES ( If the rotation is changing), the process proceeds to step S93. If NO (not changing the rotation), the process returns to step S91.

  In step S93, following the determination that the rotation is changing in step S92, the oil pressure reduction inertia phase control is performed, and the process proceeds to step S94. In this hydraulic pressure reduction inertia phase control, a second hydraulic pressure command is issued from the AT controller 7 to lower the engagement hydraulic pressure than the normal hydraulic pressure during the inertia phase control in the normal shift control and to increase the sliding engagement time of the engagement side frictional engagement element. Output to the clutch hydraulic unit 8.

  In step S94, following execution of the oil pressure lowering inertia phase control in step S93, MG torque cut control is performed, and the process proceeds to step S95.

  In step S95, following the execution of the MG torque cut control in step S94, is a rotation synchronization determination condition (= condition in which the gear ratio has completely shifted to the post-shift gear ratio) established to eliminate the differential rotation of the engagement side frictional engagement element? If YES (rotation synchronization determination condition is satisfied), the process proceeds to step S96. If NO (rotation synchronization determination condition is not satisfied), the process returns to step S93.

  In step S96, following the determination that the rotation synchronization determination condition is satisfied in step S95, the engagement side frictional engagement element is shifted to the complete engagement state, the shift end phase (post-processing) control is performed, and the process proceeds to the end. At this time, the open side frictional engagement element shifts to a fully open state.

  FIG. 13 is a flowchart showing the flow of the second cold-time shift control process in step S210 (second cold-time shift control unit).

  In step S11, torque phase control is performed, and the process proceeds to step S12.

  In step S12, following execution of torque phase control in step S11, it is determined whether or not the transmission input rotational speed is changing, in other words, whether or not the torque phase has shifted to the inertia phase, and YES ( If the rotation is changing), the process proceeds to step S13. If NO (not changing the rotation), the process returns to step S11.

  In step S13, following the determination that the rotation is changing in step S12, the hydraulic pressure increase inertia phase control is performed, and the process proceeds to step S14. In this hydraulic pressure increase inertia phase control, a hydraulic pressure command for increasing the engagement hydraulic pressure is output from the AT controller 7 to the second clutch hydraulic unit 8 than the normal hydraulic pressure during the normal inertia phase control.

  In step S14, following execution of the hydraulic pressure increase inertia phase control in step S13, MG torque cut control is performed, and the process proceeds to step S15.

  In step S15, following execution of the MG torque cut control in step S14, is a rotation synchronization determination condition (= condition in which the gear ratio has completely shifted to the post-shift gear ratio) established to eliminate the differential rotation of the engagement side frictional engagement element? If YES (rotation synchronization determination condition is satisfied), the process proceeds to step S16. If NO (rotation synchronization determination condition is not satisfied), the process returns to step S13.

  In step S16, following the determination that the rotation synchronization determination condition is satisfied in step S15, the engagement side frictional engagement element is shifted to the complete engagement state, the shift end phase (post-processing) control is performed, and the process proceeds to the end. At this time, the open side frictional engagement element shifts to a fully open state.

Next, the operation will be described.
In the control apparatus for the electric vehicle according to the second embodiment, the process proceeds from step S205 to step S206 to step S207 or step S208 in the flowchart of FIG. 11, and the hydraulic oil of the automatic transmission AT is based on the counted standby time T. Judgment of the state of. This eliminates the need for an oil temperature detecting means for detecting the operating oil temperature, thereby reducing the cost.

Next, the effect will be described.
In the control apparatus for the electric vehicle according to the second embodiment, the following effects can be obtained in addition to the effects (1) to (3) of the first embodiment.

  (5) The hydraulic oil determination means (step S208) is configured to determine the state of the hydraulic oil based on the length of a standby control time (standby time) T of the engagement hydraulic pressure. For this reason, even if it does not use the oil temperature detection means which detects the temperature of hydraulic fluid, a hydraulic fluid state can be judged accurately and cost reduction can be aimed at.

  As described above, the vehicle occupant protection device of the present invention has been described based on the first embodiment and the second embodiment. However, the specific configuration is not limited to these embodiments, and each claim in the claims is described. Design changes and additions are permitted without departing from the spirit of the invention according to the paragraph.

  In the first and second embodiments, the shift control process in the case of auto upshifting has been described, but the control apparatus for an electric vehicle of the present invention can be applied even in the case of downshifting. In this case, MG torque up control (control to increase MG torque) is performed when inertia phase control is performed.

  In the first embodiment, an example in which the control device for an electric vehicle according to the present invention is applied to an FR hybrid vehicle is shown. However, not only an FF hybrid vehicle but also a drive source includes only a motor or only a motor / generator. It can also be applied to electric vehicles such as electric vehicles and fuel cell vehicles. In short, the present invention can be applied to any electric vehicle equipped with a stepped automatic transmission at a downstream position of a drive source having a motor.

MG Motor / Generator (Motor)
AT automatic transmission 4 battery

Claims (5)

An electric vehicle that includes an automatic transmission that is disposed downstream of a drive source having a motor and achieves a plurality of shift speeds by changing friction engagement elements, and a shift control means that connects and disconnects the friction engagement elements at the time of shifting. In the control device of
Hydraulic oil determining means for determining the state of hydraulic oil of the automatic transmission; and battery determining means for determining the state of a battery that supplies power to the motor;
The shift control means lowers the engagement hydraulic pressure of the friction engagement element to reduce the sliding engagement time of the friction engagement element when the hydraulic oil is in a cold state and the battery is in the first cold state. A control device for an electric vehicle, comprising: a first cold-time shift control unit that executes an increasing oil pressure lowering inertia phase control. In the control device of the electric vehicle according to claim 1,
The shift control means executes second hydraulic pressure increase inertia phase control for increasing the engagement hydraulic pressure of the friction engagement element when the hydraulic oil is in a warm-up state and the battery is in a cold-down state. A control device for an electric vehicle, comprising a cold-time shift control unit. In the control apparatus for the electric vehicle according to claim 1 or 2,
The control apparatus for an electric vehicle, wherein the shift control means includes a motor torque cut control unit that reduces torque from the motor when downshifting. In the control apparatus of the electric vehicle as described in any one of Claims 1-3,
Oil temperature detecting means for detecting the operating oil temperature of the automatic transmission;
The control device for an electric vehicle, wherein the hydraulic oil determination means determines the state of the hydraulic oil based on an oil temperature detection value. In the control apparatus of the electric vehicle as described in any one of Claims 1-3,
The control device for an electric vehicle, wherein the hydraulic oil determination means determines the state of the hydraulic oil based on a length of standby control time of the engagement hydraulic pressure.

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