A branched power transmission having several transmission ratio ranges with a steplessly adjustable transmission ratio. A drive shaft is connected to both shafts of a variable speed unit through a distributor transmission, which shafts in turn are connected with the input shafts of a parallel gearbox through respective clutches. Two transmission ratio ranges differ from each other through the transmission ratio of an input shaft of the parallel gearbox and its output shaft. Additionally, the power-producing transmission can include an electrical machine. A further embodiment includes a variable speed unit, a first planetary transmission connected with a drive shaft, the input shaft of the variable speed unit and a connecting shaft, and a second planetary transmission that is connected with the connecting shaft of the output shaft of the variable speed unit and an output shaft, and an electrical machine that is non-rotatably connected with the connecting shaft.