Electric drive system

An electric drive system for or in a motor vehicle, comprising:

• at least one synchronous machine which has a double rotor and a distributed winding placed in a stator core, wherein the double rotor is constructed from flux-carrying material consisting of solid material, wherein the winding is designed to be self-supporting for torque support;
• and
• at least one three-level or multi-level inverter circuit which is coupled to the synchronous machine at a load output and which is designed to convert a direct voltage received on the supply side into an alternating voltage, via which the synchronous machine can be driven via the load output,
• wherein the inverter circuit has a controllable three-level or multi-level inverter,
• wherein the inverter circuit has an operating mode setting device which is designed to change the inverter from three-level or multi-level operation to two-level operation and vice versa in dependence upon an overall efficiency of the electric drive system, wherein the overall efficiency is a sole function of the detected phase current of the synchronous machine or a function of at least one further property of the synchronous machine influencing the overall efficiency.

An electric drive system for or in a motor vehicle, comprising:

• at least one synchronous machine which has a double rotor and a distributed winding placed in a stator core, wherein the double rotor is constructed from flux-carrying material consisting of solid material, wherein the winding is designed to be self-supporting for torque support;
• and
• at least one three-level or multi-level inverter circuit which is coupled to the synchronous machine at a load output and which is designed to convert a direct voltage received on the supply side into an alternating voltage, via which the synchronous machine can be driven via the load output, wherein the inverter circuit has a controllable three-level or multi-level inverter,
• wherein the inverter has a first driver level and at least one second driver level, wherein the second driver level is designed to carry output load currents to the load output which are smaller than the output load currents provided by the first driver level.