A hybrid vehicle includes an engine, an electric machine, a transmission, and a controller. The transmission is configured to alter clutch pressures in preparation for an upcoming shift between discrete gear ratios (e.g., input-to-output ratio). For example, the clutch pressures may spike to a heightened magnitude to prepare for the upcoming shift. The electric machine is configured to selectively propel the vehicle and perform regenerative braking. If regenerative braking demands occur during the clutch pressures being heightened during shift preparation, the controller is programmed to stop the preparing of the clutches. This can be done by reducing the clutch pressures back to their pre-preparation magnitude. The upcoming shift can be cancelled or delayed.

An initial variation learning control is executed when a learning condition is satisfied each time the learning condition is satisfied, with the aim of absorbing initial variations of manufacturing errors or variations of components of a second clutch (CL2). When the number of times of learning control is counted and this becomes a predetermined number (e.g. five times), after that, a deterioration variation learning control, which is equivalent to the initial variation learning control, is executed only once a trip from ON of a key switch to OFF of the key switch. With this, a frequency of execution of the learning control can be reduced, and the number of times of the learning can be reduced. It is therefore possible to suppress energy consumption and improve energy efficiency in stand-by pressure learning control of the second clutch that serves as a starter clutch.

A control method of a dual clutch transmission for a hybrid electric vehicle, and a control system for the dual clutch transmission. The control method includes: a handover step of performing a handover process of a transmission while controlling clutch torque of an engaging-side input shaft to maintain a rotational speed change rate of the engaging-side input shaft at a reference change rate; and an actual shifting step of synchronizing a rotational speed of a motor with a rotational speed of the engaging-side input shaft when the first finish determining step determines that the handover process has finished, and of increasing a rotational speed change rate of the motor by increasing motor torque when a synchronization rate is a reference synchronization rate or less.

Systems and methods for improving operation of a hybrid vehicle are presented. In one example, driveline operation may be adjusted in response to operating the hybrid vehicle in a four wheel drivel low gear range. The approaches may improve vehicle drivability and reduce driveline degradation.

A control apparatus for a hybrid vehicle includes a low temperature time hydraulic control section (11a) to perform a low temperature time hydraulic control to restrain a discharge quantity of operating oil from an oil pump (4) by limiting a line pressure of a transmission (7) at an engine cold time to a predetermined value smaller than a maximum value of a line pressure command pressure for a predetermined time period. The hydraulic control by this low temperature time hydraulic control section (11a) is continued until the motor is started after the start of the engine and a first clutch (3) is engaged at the time of low temperature of engine (1). By so doing, the control apparatus can prevent the oil pump from being stopped by inappropriate starting timing of the low temperature time hydraulic control.

The present invention relates to a drivetrain having a first clutch, which has an input side and an output side which is selectively connectable in terms of rotational drive to the input side, and having a transmission, which has a transmission shaft which is connected or connectable in terms of rotational drive to the output side and which is selectively connectable in terms of rotational drive to a gearwheel by means of a second clutch, wherein a rotor of an electric machine is arranged on the output side, and the electric machine, in motor operation, can be controlled or regulated so as to cause the rotational speeds of the transmission shaft and of the gearwheel to be approximated to or aligned with one another before the closure of the second clutch. The present invention also relates to a method for performing gearshifts in a transmission within a drivetrain of the type according to the invention.

A powertrain system employing multiple propulsion torque actuators is described. A method for controlling the powertrain system includes interpreting a driver request, including determining a driver torque request and a regenerative braking request based upon driver inputs to an accelerator pedal and a brake pedal. A desired request is determined based upon the driver torque request and the regenerative braking request. Torque limits for the powertrain system are coordinated based upon the desired request, the driver torque request, and a previous driver torque request to determine upper and lower output torque limits, and the upper and lower output torque limits are combined with system constraints to generate a final torque request. The final torque request is employed to determine torque commands for the propulsion torque actuators, and the propulsion torque actuators are controlled based upon the torque commands for the propulsion torque actuators.

A method for operating a drive device for a motor vehicle including an internal combustion engine and an electrical machine. A drive shaft of the internal combustion engine can be coupled to a machine shaft of the electrical machine by a shift clutch. The shift clutch is opened in a first shift state for decoupling the internal combustion engine and the electrical machine, and is closed in a second shift state for coupling the internal combustion engine and the electrical machine. When a switching occurs from the first shift state to the second shift state, a clutch target torque that is set at the shift clutch is determined in a first mode of operation by a closed-loop control, and in a second mode of operation is determined by an open-loop control.

A hybrid system includes a hybrid module that is located between an engine and a transmission. The hybrid system includes an energy storage system for storing energy from and supplying energy to the hybrid module. An inverter transfers power between the energy storage system and the hybrid module. The hybrid system also includes a cooling system, a DC-DC converter, and a high voltage tap. The hybrid module is designed to recover energy, such as during braking, as well as power the vehicle. The hybrid module includes an electrical machine (eMachine) along with electrical and mechanical pumps for circulating fluid. A clutch provides the sole operative connection between the engine and the eMachine. The hybrid system further incorporates a power take off (PTO) unit that is configured to be powered by the engine and/or the eMachine.

A hybrid vehicle includes an engine, an electric machine, a transmission, and a controller. The transmission is configured to alter clutch pressures in preparation for an upcoming shift between discrete gear ratios (e.g., input-to-output ratio). For example, the clutch pressures may spike to a heightened magnitude to prepare for the upcoming shift. The electric machine is configured to selectively propel the vehicle and perform regenerative braking. If regenerative braking demands occur during the clutch pressures being heightened during shift preparation, the controller is programmed to stop the preparing of the clutches. This can be done by reducing the clutch pressures back to their pre-preparation magnitude. The upcoming shift can be cancelled or delayed.