A method determines the biting point of a hybrid disconnect clutch of a hybrid vehicle. The hybrid disconnect clutch disconnects or connects an internal combustion engine and a first electric motor, which is arranged on the output side. A second electric motor, which is arranged on the internal combustion engine side and is rigidly connected to the internal combustion engine, is operated at a constant rotational speed during electric travel by means of the first electric motor. The hybrid disconnect clutch is moved from the open state toward the closed state and the load on the second electric motor is monitored. When the load on the second electric motor reaches a predefined load threshold value, it is determined that the biting point has been reached.

A method for operating a hybrid vehicle that includes a prime mover (1) with an internal combustion engine (2), an electric machine (3), a transmission (4) connected between the prime mover (1) and a driven end (5), and multiple shift elements, including a separating clutch (7) connected between the internal combustion engine (2) and the electric machine (3), and a starting component (8), is provided. After release of a brake pedal (12) or together with the release of the brake pedal (12) for a driving start or an crawling start, an engagement speed threshold (22) for the starting component (8) is established below an idling speed of the prime mover (1) and a previously disengaged starting component (8) is engaged. A control unit (9, 10, 11) for carrying out such a method is also provided.

A method for operating a hybrid vehicle that includes a prime mover (1) with an internal combustion engine (2), an electric machine (3), a transmission (4) connected between the prime mover (1) and a driven end (5), and multiple shift elements, including a separating clutch (7) connected between the internal combustion engine (2) and the electric machine (3), and a starting component (8), is provided. After release of a brake pedal (12) or together with the release of the brake pedal (12) for a driving start or an crawling start, an engagement speed threshold (22) for the starting component (8) is established below an idling speed of the prime mover (1) and a previously disengaged starting component (8) is engaged. A control unit (9, 10, 11) for carrying out such a method is also provided.

A method of controlling an engine and a transmission of a hybrid vehicle includes steps of: determining whether the vehicle starts, determining an engine RPM and a gear stage of a transmission if the vehicle has started, determining whether the engine RPM has reached an engine speed control point, determining an engine target RPM and an engine target RPM slope of the vehicle when it is determined that the engine RPM has reached the engine speed control point, controlling the engine RPM of the vehicle to follow the engine target RPM and the engine target RPM slope, determining whether the engine RPM has slipped compared to the target engine RPM, and performing PID control to follow the engine target RPM if the engine RPM slips compared to the engine target RPM.

A method of controlling an engine and a transmission of a hybrid vehicle includes steps of: determining whether the vehicle starts, determining an engine RPM and a gear stage of a transmission if the vehicle has started, determining whether the engine RPM has reached an engine speed control point, determining an engine target RPM and an engine target RPM slope of the vehicle when it is determined that the engine RPM has reached the engine speed control point, controlling the engine RPM of the vehicle to follow the engine target RPM and the engine target RPM slope, determining whether the engine RPM has slipped compared to the target engine RPM, and performing PID control to follow the engine target RPM if the engine RPM slips compared to the engine target RPM.

A method and system for shifting a transmission that includes one or more mechanical clutches without clutch plates is described. In one example, a torque output of an electric machine is adjusted in response to a request to shift a transmission so that forces that hold the mechanical clutch in an engaged position may be reduced.

A method and system for shifting a transmission that includes one or more mechanical clutches without clutch plates is described. In one example, a torque output of an electric machine is adjusted in response to a request to shift a transmission so that forces that hold the mechanical clutch in an engaged position may be reduced.

Methods and systems for tuning vehicle drivability are provided. The vehicle system includes, in one example, a vehicle control unit (VCU) that is designed to electronically communicate with a human machine interface (HMI). In the system, the VCU is designed to, in reaction to receiving an acceleration or deceleration request from the HMI, send a virtual acceleration or deceleration command to a transmission control unit (TCU), where the virtual acceleration or deceleration command correlates to the acceleration or deceleration request and the correlation is user adjustable via a user interface (UI) of the VCU.

Systems and methods for operating a hybrid vehicle are described. In one example, the automatic engine stopping may be inhibited so that an engine may be restarted during change of mind conditions without generating a large driveline torque disturbance. The engine stopping may be inhibited based on a inhibit engine pull-down torque threshold.

Systems and methods for operating a hybrid vehicle are described. In one example, the automatic engine stopping may be inhibited so that an engine may be restarted during change of mind conditions without generating a large driveline torque disturbance. The engine stopping may be inhibited based on a inhibit engine pull-down torque threshold.