A control apparatus for a vehicle includes an electronic control unit that is configured to set a value of a target generated voltage of the generator. The electronic control unit is configured to execute power generation control to control a generated voltage of a generator. The electronic control unit is configured to maintain a value of the generated voltage in the power generation control to be constant during an upshift gear change when the upshift gear change control of a transmission is executed while the lock-up clutch control is executed during deceleration of the vehicle. The electronic control unit is configured to increase the value in the power generation control during the downshift control to the value of the target generated voltage at a first specified rate when a downshift gear change of the transmission is executed while the lock-up clutch control is executed during the deceleration.

The drive system from the engine (1) to the drive wheels (7) of a vehicle is equipped with a torque converter (2), which has a lock-up clutch (3), and a variator (4). Said engined car is provided with a lock-up control means for controlling the engagement/disengagement of the lock-up clutch (3) and a gear change mode switch-controlling means (FIG. 8) for performing control to switch between a “continuously variable gear change mode” and a “DSTEP gear change mode.” While traveling, the gear change mode switch-controlling means (FIG. 8) prohibits gear change by the “DSTEP gear change mode” when the detected oil temperature is at or below a lock-up engagement-permitting threshold for permitting engagement of the lock-up clutch (3) and allows gear change by the “DSTEP gear change mode” when the detected oil temperature is higher than the lock-up engagement-permitting threshold.

A transmission is provided having a control module, an input member, an output member, four planetary gear sets, a plurality of interconnecting members, and a plurality of torque transmitting devices. Each of the planetary gear sets includes first, second and third members. The torque transmitting devices include clutches and brakes. The control module includes a control logic sequence for performing a coasting downshift of the transmission.

A method for controlling an electric drive unit (EDU) having a motor-driven torque converter includes receiving a request signal indicative of a requested output torque of the EDU, and operating the motor at a target motor speed using the requested output torque. The target motor speed minimizes system losses while achieving the requested output torque. When the requested output torque remains below a calibrated threshold and a turbine speed is less than a corner speed of the motor, a torque converter clutch (TCC) transitions to or remains in a locked state. The controller commands the TCC to transition to an unlocked state to reach the target motor speed, thereby selectively enabling torque multiplication. A powertrain system includes a driven load and the EDU. A computer readable storage medium may include executable instructions for performing the method.

A powertrain (12) for a vehicle (10) is disclosed. The power-train (12) comprises: a combustion engine (24), (ii) a drivetrain (14) having a torque converter (32) with a first state of operation in which the input (34) of the torque converter (32) is locked to the output (36) of the torque converter (32) and a second sate of operation in which the input (34) of the torque converter (32) is not locked to the output (36) of the torque converter (32) for allowing slippage. The drivetrain also has a final drive (44) for supplying torque to the drive wheel (16) from the torque converter (32), wherein the final drive (44) is coupled to the torque converter (32) at a fixed gear ratio. The powertrain (12) further comprises: (iii) a first electric motor (28) configured to supply torque to the drivetrain (14) on the output-side of the torque converter (32).

A method for operating a drive train of a motor vehicle includes performing a startup operation of the motor vehicle or a stopping operation of the motor vehicle. A starting component (3) is engaged or bridged during the startup operation or the stopping operation of the motor vehicle. The startup operation is driven by a drive source (1). The method also includes comparing an actual value of an output shaft (22) based variable with a target value of the output shaft (22) based variable during the startup operation or the stopping operation and, on reaching or exceeding a specific deviation of the actual value from the target value, moving the starting component (3) into a slipping state. The starting component (3) transmits torque in the slipping state. A related drive train module for a motor vehicle is also provided.

A control device for a vehicle is provided. The vehicle includes an engine, an accessory, a continuously variable transmission, and a lock-up clutch. The control device includes an electronic control unit. The electronic control unit is configured to: when the load state is less than a predetermined value, control the speed ratio of the continuously variable transmission and the rotational speed of the engine such that the rotational speed of the engine during engagement of the lock-up clutch is kept at a first rotational speed; and when the load state is greater than or equal to the predetermined value, control the speed ratio of the continuously variable transmission and the rotational speed of the engine such that the rotational speed of the engine during engagement of the lockup clutch becomes a second rotational speed higher than the first rotational speed.

Systems and methods for improving operation of a hybrid vehicle driveline are presented. In one example, a margin torque for closing a torque converter clutch is adjusted responsive to a state of engine operation.

A control device for a vehicle including a variable compression ratio mechanism arranged to vary an engine compression ratio of an internal combustion engine, and a torque converter which includes a lock-up mechanism, and which is disposed between the internal combustion engine and a transmission, has a controller configured to switch the engine compression ratio from a high compression ratio to a low compression ratio, and to switch the lock-up mechanism from a lock-up OFF state to a lock-up ON state. When the controller is switching the engine compression ratio from the high compression ratio to the low compression ratio, the controller starts switching the lock-up mechanism to the lock-up ON state when a current engine compression ratio is equal to or smaller than a permissible compression ratio which is between the high compression ratio and the low compression ratio.

A transmission gear control apparatus for a vehicle is provided. The vehicle includes an automatic transmission, a torque converter, and an accelerator operation amount sensor. The torque converter is disposed between the engine and the automatic transmission. The transmission gear control apparatus includes an electronic control unit. The electronic control unit is configured to: (i) control switching of a transmission gear stage of the automatic transmission at least on a basis of a change in vehicle speed of the vehicle; (ii) control lockup of a lock-up clutch of the torque converter on a basis of a state of the vehicle; and (iii) control the automatic transmission when the accelerator operation amount is equal to or larger than a specified value such that an upshift of the automatic transmission is performed at a higher vehicle speed as a rotation difference between input and output of the torque converter is reduced.