Systems and methods for managing starting of an internal combustion engine during shifting of a transmission of a hybrid vehicle are presented. In one example, torque converter impeller speed or a torque multiplication ratio may be indicative of an unintended transmission downshift during engine starting so that an engine starting device may be switched to improve vehicle operation.

A method actively dampens a start-up resonance of a torsional damper when starting an internal combustion engine. The torsional damper (4) is fixed between an internal combustion engine (1) and a secondary side (5) of a torsional elasticity, and the internal combustion engine (1) is started using a starter generator (3) arranged on a side of the internal combustion engine (1) counter to the torsional elasticity. A counter excitation is applied to a torque generated by the starter generator (3) when the internal combustion engine (1) is started, which counter excitation is modulated on the basis of a parameter of the internal combustion engine (1) which changes when the internal combustion engine (1) is being started.

Systems and methods for operating various components of a hybrid driveline during starting of an internal combustion engine are described. In one example, output of an electric machine is not adjusted during engine starting when a speed of the electric machine exceeds a threshold speed so that torque reporting is accurate and to ensure combustion is reliable.

A starting apparatus for internal combustion engines, having a drive pinion for engagement into a ring gear of the internal combustion engine, an electrical rotary actuator and an electrical linear actuator, the rotary actuator to rotate the drive pinion and the linear actuator to slide a pinion, and the electrical linear actuator having a linear-stroke magnet that has a sliding armature is moved by a retraction winding, within the retraction winding, along a sliding armature axis, having a holding winding by which the sliding armature can be held in a retracted state. The linear actuator also actuates a switching apparatus to activate the electrical rotary actuator into a second actuation stage. A second retraction winding is connected in parallel with the first retraction winding, such that the first retraction winding can be shut off by a normally closed switch while a current path through a second retraction winding is closed.

An acceleration method for a hybrid drivetrain includes providing the hybrid drivetrain, setting an initial torque transmission ratio of a belt-drive transmission to a lower transmission ratio, and opening a first disconnect clutch to interrupt torque transmission between an internal combustion engine and an electric machine. The method also includes receiving an acceleration command, shifting the torque transmission ratio with a transmission adjustment gradient from the lower transmission ratio towards an upper transmission ratio, increasing a rotor speed of a rotor shaft of the electric machine with a rotor shaft adjustment gradient, and engaging a first disconnect clutch to rotate an ICE shaft to start the internal combustion engine and increase a rotational speed of the ICE shaft towards a current rotor speed.

Systems and methods for starting an engine that is incorporated into a hybrid vehicle driveline are described. In one example, a torque converter clutch is fully opened if a threshold amount has transpired after a request for torque converter clutch slip is requested but not delivered. Further, the torque converter clutch may be fully opened if a commanded torque converter clutch torque capacity is less than a threshold torque capacity.

An engine start system of a hybrid vehicle includes a converter circuit unit converting voltage and outputting the converted voltage and a switch having a first terminal connected to an output terminal of the converter circuit unit and a second terminal selectively forming an electrical connection with the first terminal. A diode has an anode connected to the second terminal and a cathode connected to the first terminal. A battery is connected to the second terminal. A low-voltage starter connected to the battery and provides rotary power to start an engine in a stopped state by converting battery power into rotational energy. A controller opens the switch and supplies driving power to the low-voltage starter when the engine is started.

Systems and methods for operating various components of a hybrid driveline during starting of an internal combustion engine are described. In one example, output of an electric machine is not adjusted during engine starting when a speed of the electric machine exceeds a threshold speed so that torque reporting is accurate and to ensure combustion is reliable.

Internal combustion engine cranking is carried out including with a limited overlapping of cranking with a starter motor and a starter/generator during at least the initial compression stroke during a cranking cycle.

A method actively dampens a start-up resonance of a torsional damper when starting an internal combustion engine. The torsional damper (4) is fixed between an internal combustion engine (1) and a secondary side (5) of a torsional elasticity, and the internal combustion engine (1) is started using a starter generator (3) arranged on a side of the internal combustion engine (1) counter to the torsional elasticity. A counter excitation is applied to a torque generated by the starter generator (3) when the internal combustion engine (1) is started, which counter excitation is modulated on the basis of a parameter of the internal combustion engine (1) which changes when the internal combustion engine (1) is being started.