It is herein described a system and a corresponding method to carry out the selective coupling and uncoupling of an alternator in relation to an engine crankshaft pulley. The alternator is kept coupled or uncoupled depending on the detected battery charge, and both coupling and uncoupling are performed in two different steps and lagged in time, one step providing the electric coupling or uncoupling, and the other step providing the mechanical coupling or uncoupling.

A control strategy is provided for a hybrid vehicle that will increase drivability during low or decreasing driver demands. Coordination between shifting the transmission and stopping or (non-demand) starting of the engine can increase drivability. The vehicle includes a motor/generator with one side selectively coupled to the engine and another side selectively coupled to the transmission. The control strategy acts when an engine start or stop is requested while driver demand is decreasing and a shift of the transmission is demanded. To inhibit these events from proceeding simultaneously, the control strategy delays the engine from starting or stopping until the transmission has finished shifting, or vice versa.

A controller executes a method to manage an engine connect/disconnect decision in a powertrain having an engine, transmission, electric machine, and a battery pack and power inverter module (“TPIM”). In response to vehicle ground speed being less than a calibrated maximum electric vehicle accelerator pedal signal (“EV.sub.APS”) level, the controller calculates a delta APS (“ΔAPS”) value by subtracting a scaled APS value from the actual APS level. The scaled APS value is a scaled variant of a maximum EV.sub.APS value selected from a maximum EVS.sub.APS table, the latter populated based on inverter temperature, state of charge of the battery pack, and ground speed. When the ΔAPS value exceeds a threshold, the controller connects the engine to the transmission via an engine disconnect clutch. The engine is disconnected based on acceleration of the vehicle and the above-noted factors.

A controller executes a method to manage an engine connect/disconnect decision in a powertrain having an engine, transmission, electric machine, and a battery pack and power inverter module (TPIM). In response to vehicle ground speed being less than a calibrated maximum electric vehicle accelerator pedal signal (EV.sub.APS) level, the controller calculates a delta APS (PS) value by subtracting a scaled APS value from the actual APS level. The scaled APS value is a scaled variant of a maximum EV.sub.APS value selected from a maximum EVS.sub.APS table, the latter populated based on inverter temperature, state of charge of the battery pack, and ground speed. When the APS value exceeds a threshold, the controller connects the engine to the transmission via an engine disconnect clutch. The engine is disconnected based on acceleration of the vehicle and the above-noted factors.

A control strategy is provided for a hybrid vehicle that will increase drivability during low or decreasing driver demands. Coordination between shifting the transmission and stopping or (non-demand) starting of the engine can increase drivability. The vehicle includes a motor/generator with one side selectively coupled to the engine and another side selectively coupled to the transmission. The control strategy acts when an engine start or stop is requested while driver demand is decreasing and a shift of the transmission is demanded. To inhibit these events from proceeding simultaneously, the control strategy delays the engine from starting or stopping until the transmission has finished shifting, or vice versa.

Provided is a lock-up clutch control device of a vehicle in which a torque converter with a lock-up clutch is disposed between an engine and a transmission. This control device has a coasting capacity learning control section configured to decrease a LU differential pressure command value for the lock-up clutch during accelerator release operation and, when a slip of the lock-up clutch is detected during decrease of the LU differential pressure command value, update the LU differential pressure command value at the time of detection of the slip as a LU differential pressure learning value balanced with a coasting torque. The coasting capacity learning control section is further configured to, when operation of the PTC heater intervenes during coasting capacity learning control, correct the LU differential pressure command value by adding thereto a LU differential pressure correction value that corresponds to an increase of input torque to the lock-up clutch.

A method of controlling a damper pulley clutch for selectively transmitting power of an engine to engine accessories, may include determining, by a controller, whether a vehicle is driven in a fuel-cut mode under deceleration of the vehicle and controlling the damper pulley clutch, by the controller, to be engaged upon determining that the vehicle is driven in the fuel-cut mode and to be disengaged upon determining that the vehicle is not driven in the fuel-cut mode.

Provided is a lock-up clutch control device of a vehicle in which a torque converter with a lock-up clutch is disposed between an engine and a transmission. This control device has a coasting capacity learning control section configured to decrease a LU differential pressure command value for the lock-up clutch during accelerator release operation and, when a slip of the lock-up clutch is detected during decrease of the LU differential pressure command value, update the LU differential pressure command value at the time of detection of the slip as a LU differential pressure learning value balanced with a coasting torque. The coasting capacity learning control section is further configured to, when operation of the PTC heater intervenes during coasting capacity learning control, correct the LU differential pressure command value by adding thereto a LU differential pressure correction value that corresponds to an increase of input torque to the lock-up clutch.

An example system for disconnecting a driven member from a driving member is described. The system includes a vibration detection device configured to output vibration signals indicative of vibration levels of the driven member. The system also includes a controller including at least one processor. The controller is arranged to (i) determine that a vibration signal output by the vibration detection device satisfies a threshold condition and (ii) based at least on the determination that the vibration signal satisfies the threshold condition, trigger a mechanical disconnection of the driven member from the driving member by a mechanical disconnect device.

A method of controlling a damper pulley clutch for selectively transmitting power of an engine to engine accessories, may include determining, by a controller, whether a vehicle is driven in a fuel-cut mode under deceleration of the vehicle and controlling the damper pulley clutch, by the controller, to be engaged upon determining that the vehicle is driven in the fuel-cut mode and to be disengaged upon determining that the vehicle is not driven in the fuel-cut mode.