Method for operating transmission i.e. power-split hybrid-transmission, for hybrid vehicle, involves selecting gear of transmission based on modified reference speed value and determined tolerance range

摘要

The method involves providing a reference speed value for initial speed of a transmission. Tolerance range (16) for transmission ratio of one of gears such as virtual gears (VG1-VG8) and fixed gears, of the transmission is determined, and the speed value is modified based on an operating condition of a vehicle. One of the gears of the transmission is selected based on the modified speed value and the determined tolerance range. An upper limit (18) of the tolerance range of the ratio is calculated from a sum of the initial speed corresponding to the gear, and an upper limit value.