METHOD FOR MOVING OFF A HYBRID VEHICLE

A method for moving off of a hybrid vehicle with a propulsion system () including a planetary gear with three components: a sun gear (), a ring gear () and a planet wheel carrier (). The output shaft () of a combustion engine () is connected to a first component of an input shaft () of a gearbox () is connected to a second component and the rotor () of an electric machine () is connected to a third component. The propulsion system has a locking device transferable between a locking position and a releasing position respectively, in which the components rotate as a unit and with different rotation speeds respectively. The method starts from an initial state with the combustion engine idle, the locking device in the releasing position and a gear, appropriate for moving off, engaged in the gearbox. The electric machine is controlled to apply a positive torque on the third component of the planetary gear, and the rotation speed of the combustion engine is controlled towards a constant rotation speed. A reaction torque is created and gives rise to a demanded driving torque, whereby the vehicle moves off.