A method for controlling a power-split gear shift device in a vehicle by providing an electric variator and a transmission with variable gear shift and connecting a drive motor to a traction drive of the vehicle. The electric variator has a compound gear train with at least one first and at least one second electric machine. The method also includes providing a controller for the electric machines for steplessly varying a gear shift of the compound gear train. Upon detection of an external power requirement by an electric consumer, a gear shift region of the transmission with variable gear shift is set to operate the first electric machine in a generator mode and to operate the second electric machine to compensate for an existing power deficit or a power excess relative to an external power demand.

A vehicle control system and method is applied to a vehicle including: a continuously variable transmission for changing a speed ratio continuously that is disposed between an input shaft and an output shaft; a geared transmission that is disposed parallel to the continuously variable transmission, and that is adapted to establish a speed ratio that cannot be established by the continuously variable transmission; and a friction clutch that is brought into engagement to switch a torque transmission route from a route including the geared transmission to a route including the continuously variable transmission. The vehicle control system is configured to start a speed change operation of the continuously variable transmission before a commencement of clutch-to-clutch shifting between the friction clutches when switching the torque transmission route from the route including the geared transmission to the route including the continuously variable transmission.

An electrically variable transmission for an off-road vehicle including an internal combustion engine with a crankshaft. The electrically variable transmission includes a compound planetary gear assembly having a first planetary gear set with a first ring gear, a first sun gear and a first planet carrier and a second planetary gear set with a second ring gear, a second sun gear and a second planet carrier. The planet carriers are coupled together for common rotation and are coupled to an output gear for common rotation therewith. The first ring gear is in torque transferring communication with the crankshaft. The first sun gear is in torque transferring communication with a first motor generator. The second sun gear is in torque transferring communication with a second motor generator. The rotational axes of the compound planetary gear assembly and each of the motor generators are parallel rotational axes.

A motor-gearbox arrangement, comprising a gearbox arranged to as to selectively couple a first input and a second input to the output via a plurality of epicyclic gears a first electric motor coupled to the first input so as to rotate the first input; and a second electric motor coupled to the second input so as to rotate the second input; in which the clutches and the epicyclic gears which are connected to the input and the output and to other epicyclic gears of the gear train.