Device and method for operation of at least one electrical machine for a motor vehicle. In order to coordinate torque requirements for the propulsion system and voltage requirements for the vehicle power supply system and at least one battery for the vehicle power supply system, a voltage reference variable is formed for the voltage requirements for the vehicle power supply system, and a torque reference variable is formed for the torque requirements of the propulsion system. The voltage reference variable is limited by upper and lower torque limit values which must not be overshot or undershot in the event of changes to the voltage reference variable. The torque reference variable is limited by voltage limit values which must not be overshot or undershot in the event of torque changes.