Electric drive assembly

A method of controlling an electric drive assembly that comprises

• an electric machine which is configured as a high-speed electric machine with a nominal speed of at least 20,000 revolutions per minute and is provided with a high-speed rotor which is usable as a flywheel mass to store kinetic energy;
• a superimposed transmission with exactly three connecting elements, consisting of a drive element, a regulating element, and a driven element, wherein the superimposed transmission is configured in the form of a planetary transmission with a sun gear that forms the drive element and that is rotatingly driveable by the electric machine around a driving axis at more than 20,000 revolutions per minute, and with a hollow gear that is connected to the regulating element and is rotatable around a regulating axis, and with a planetary carrier that forms the driven element and carries a plurality of planetary gears via which the hollow gear and the sun are drivingly connected;
• an electro-magnetic regulating device that is coaxially arranged relative to the superimposed transmission and provided for variably regulating a rotational speed of the regulating element, wherein the electromagnetic regulating device comprises a stator that is connected to a stationary component and a rotor that is connected to the regulating element of the superimposed transmission in a rotationally fixed way, wherein the rotor and the stator are contactlessly arranged relative to each other, wherein the electromagnetic regulating device is configured to transmit a regulating torque to the rotor by magnetic forces acting in circumferential direction between the stator and the rotor, wherein the magnetic forces are variably adjustable,
• wherein the high-speed electric machine is arranged in a sealed dry first receiving chamber, wherein an internal pressure in the first receiving chamber is lower than an environmental pressure, and
• wherein the electromagnetic regulating device and the superimposed transmission are arranged in a sealed second receiving chamber filled with lubricant, wherein the superimposed transmission is arranged radially inside the electromagnetic regulating device;
• the method comprising:
• controlling the high-speed electric machine such that the high-speed rotor rotates at a speed of at least 20,000 revolutions per minute;
• controlling the electromagnetic regulating device in a motor mode for generating a variable rotational speed of the regulating element, wherein the rotational speed of the high-speed electric machine and the variable rotational speed of the regulating element superimpose one another for driving the driven element;
• wherein the variable speed of the regulating element is set by the electromagnetic regulating device such that the drive element rotates at a nominal speed.