Method for setting a setpoint output voltage U_setpoint of an energy supply branch of a controllable energy store, which serves to control and supply electrical energy to an n-phase electric machine, where n ≥ 1, wherein - the controllable energy store has n parallel energy supply branches (3-1, 3-2, 3-3), which • each have at least two energy storage modules connected in parallel, which each comprise at least one electrical energy storage cell having an associated controllable coupling unit, • can be connected on one side to a reference rail (T-) and • can be connected on the other side to in each case one phase (U, V, W) of the electric machine, - depending on control signals, the coupling units connect the respectively associated energy storage cells into the respective energy supply branch (3-1; 3-2; 3-3) by closing second switching elements (7, 7-312, 7-3m2) and opening first switching elements (7, 7-311, 7-3ml) or bypass the respectively associated energy storage cells by closing first switching elements (7, 7-311, 7-3ml) and opening second switching elements (7, 7-312, 7-3m2) of the respective coupling unit, in which at least one coupling unit is actuated in a pulsed manner in such a way that the arithmetic mean value of the output voltage of an energy supply branch corresponds to the setpoint output voltage U_setpoint, wherein the energy storage cells respectively associated with the at least one coupling unit are connected into the respective energy supply branch during a pulse duration and are not connected into the respective energy supply branch during a pause duration, characterized in that a setpoint output voltage U_setpoint of an energy supply branch, which is between two output voltage values U1 and U2 that can be achieved through permanent connection of energy storage cells into the energy supply branch or of energy storage cells not connected into the energy supply branch, is set by virtue of - coupling units of energy storage modules, which lead to the output voltage value U1, being controlled in such a way that the respective energy storage cells are connected permanently into the energy supply branch and - a coupling unit, which is associated with energy storage cells that would increase the voltage value from U1 to U2 in the case of permanent connection into the energy supply branch, being actuated in a pulsed manner with a duty cycle T of T = U _ setpoint − U 1 U 2 − U 1. - the controllable energy store has n parallel energy supply branches (3-1, 3-2, 3-3), which • each have at least two energy storage modules connected in parallel, which each comprise at least one electrical energy storage cell having an associated controllable coupling unit, • can be connected on one side to a reference rail (T-) and • can be connected on the other side to in each case one phase (U, V, W) of the electric machine, • each have at least two energy storage modules connected in parallel, which each comprise at least one electrical energy storage cell having an associated controllable coupling unit, • can be connected on one side to a reference rail (T-) and • can be connected on the other side to in each case one phase (U, V, W) of the electric machine, - depending on control signals, the coupling units connect the respectively associated energy storage cells into the respective energy supply branch (3-1; 3-2; 3-3) by closing second switching elements (7, 7-312, 7-3m2) and opening first switching elements (7, 7-311, 7-3ml) or bypass the respectively associated energy storage cells by closing first switching elements (7, 7-311, 7-3ml) and opening second switching elements (7, 7-312, 7-3m2) of the respective coupling unit, - coupling units of energy storage modules, which lead to the output voltage value U1, being controlled in such a way that the respective energy storage cells are connected permanently into the energy supply branch and - a coupling unit, which is associated with energy storage cells that would increase the voltage value from U1 to U2 in the case of permanent connection into the energy supply branch, being actuated in a pulsed manner with a duty cycle T of T = U _ setpoint − U 1 U 2 − U 1.