Abstract: A method for checking a model temperature of an electrical machine ascertained by a temperature model. At least one manipulated variable relating to the electrical machine is specified by a regulation of the electrical machine as a function of a setpoint variable. A model value of the manipulated variable is ascertained as a function of the manipulated variable and the model temperature from a machine model comprising at least one temperature-dependent parameter. A difference between the actual manipulated variable of the regulation and the model value of the manipulated variable and/or a difference between a variable derived from the actual manipulated variable of the regulation and a corresponding further variable derived from the model value of the manipulated variable is ascertained. The difference is compared to a limiting value and, if the limiting value is exceeded, a deviation of the model temperature from an actual temperature of the electrical machine is detected.

Abstract: A method for operating a drive system is provided in which the drive system may include at least one electric drive unit and an auxiliary drive unit. The rotor shaft of at least one electric device unit may be mounted via plain bearings. The output shaft of the auxiliary drive unit may be mounted using roller bearings. The rotor shaft may be configured to be coupled to the output shaft. The method for operating the drive system may include determining an actual rotational speed of the electric drive unit, comparing the actual rotational speed with a limit rotational speed, deactivating the electric drive unit and activating the auxiliary drive unit if the actual rotational speed is lower than the limit rotational speed, and activating the electric drive unit if the actual rotational speed is greater than the limit rotational speed. A drive system and a vehicle are also provided.

Abstract: A method and a device for checking the thermal state of an electric machine of a vehicle driven by at least two electric machines are described.

Abstract: A method for determining an intermediate circuit voltage UDC,Ideal in an electrical system, which includes a battery, a DC-DC converter, a DC-AC converter, and an electrical machine. The battery is connected to the DC-DC converter, the DC-DC converter is connected to the DC-AC converter, and the DC-AC converter is connected to the electrical machine. An intermediate circuit of the electrical system is formed by the DC-DC converter and the DC-AC converter. A line-to-line voltage ÛLL, which is applied to a conductor of the electrical machine, is determined, wherein a maximum degree of modulation mmax of the line-to-line voltage ÛLL is determined.

Abstract: A method for determination of state information, especially describing a tribological state of a drive train of a motor vehicle, wherein the drive train comprises an electric machine as a first drive machine and a second drive machine, wherein upon fulfillment of a diagnostic condition the first drive machine is operated in an electrical idling mode, in which it is electrically separated from all current sources and current sinks and coupled to at least one of the wheels of the motor vehicle, and during the operation of the first drive machine in the electrical idling mode a performance measure is acquired for the performance of the second drive machine, while at least one of the wheels of the motor vehicle is driven by the second drive machine, after which the state information is determined in dependence on the performance measure and given reference information.

Abstract: A system for a vehicle, which has a battery, a DC-DC converter, a DC-AC converter, an electric motor, and a switch. The battery is connected to the DC-DC converter and the DC-AC converter is connected to the electric motor. The switch is arranged between the DC-DC converter and the DC-AC converter, and the switch is designed, in a first switching state, to electrically connect the DC-DC converter and the DC-AC converter and to permit an exchange of electrical energy between the battery and the electric motor in order to carry out a traction process. The switch is designed, in a second switching state, to electrically isolate the DC-DC converter and the DC-AC converter, to connect the battery to an electrical charging station, and to permit an exchange of electrical energy between the battery and the electric charging station in order to carry out a charging process.

Abstract: Methods and apparatuses for determining a rotor temperature of a permanent magnet synchronous machine (PSM) of an electrically driven vehicle are described.

Abstract: A method for determining an intermediate circuit voltage UDC,Ideal in an electrical system, which includes a battery, a DC-DC converter, a DC-AC converter, and an electrical machine. The battery is connected to the DC-DC converter, the DC-DC converter is connected to the DC-AC converter, and the DC-AC converter is connected to the electrical machine. An intermediate circuit of the electrical system is formed by the DC-DC converter and the DC-AC converter. A line-to-line voltage ÛLL, which is applied to a conductor of the electrical machine, is determined, wherein a maximum degree of modulation mmax of the line-to-line voltage ÛLL is determined.

Abstract: A system for a vehicle, which has a battery, a DC-DC converter, a DC-AC converter, an electric motor, and a switch. The battery is connected to the DC-DC converter and the DC-AC converter is connected to the electric motor. The switch is arranged between the DC-DC converter and the DC-AC converter, and the switch is designed, in a first switching state, to electrically connect the DC-DC converter and the DC-AC converter and to permit an exchange of electrical energy between the battery and the electric motor in order to carry out a traction process. The switch is designed, in a second switching state, to electrically isolate the DC-DC converter and the DC-AC converter, to connect the battery to an electrical charging station, and to permit an exchange of electrical energy between the battery and the electric charging station in order to carry out a charging process.

Abstract: A method for checking a model temperature of an electrical machine ascertained by a temperature model. At least one manipulated variable relating to the electrical machine is specified by a regulation of the electrical machine as a function of a setpoint variable. A model value of the manipulated variable is ascertained as a function of the manipulated variable and the model temperature from a machine model comprising at least one temperature-dependent parameter. A difference between the actual manipulated variable of the regulation and the model value of the manipulated variable and/or a difference between a variable derived from the actual manipulated variable of the regulation and a corresponding further variable derived from the model value of the manipulated variable is ascertained. The difference is compared to a limiting value and, if the limiting value is exceeded, a deviation of the model temperature from an actual temperature of the electrical machine is detected.

Abstract: A method for operating an electrical circuit, wherein the electrical circuit includes a DC converter, an inverter and an electric machine, wherein the inverter is connected on the direct current side to the output of the DC converter and on the alternating current side to the electric machine, wherein the electric machine is operated using a torque specification and/or a rotational speed specification, wherein the level of the output voltage of the DC converter is set as a function of a current torque specification and/or a current rotational speed specification.

Abstract: A method and a system for automatic yaw torque equalization (AYTE) in an electrically driven vehicle having wheel-individual torque distribution (torque vectoring drive).

Abstract: A method for operating an electrical circuit, wherein the electrical circuit includes a DC converter, an inverter and an electric machine, wherein the inverter is connected on the direct current side to the output of the DC converter and on the alternating current side to the electric machine, wherein the electric machine is operated using a torque specification and/or a rotational speed specification, wherein the level of the output voltage of the DC converter is set as a function of a current torque specification and/or a current rotational speed specification.

Abstract: A method and a device for checking the thermal state of an electric machine of a vehicle driven by at least two electric machines are described.

Abstract: Methods and apparatuses for determining a rotor temperature of a permanent magnet synchronous machine (PSM) of an electrically driven vehicle are described.

Abstract: A method and a system for automatic yaw torque equalization (AYTE) in an electrically driven vehicle having wheel-individual torque distribution (torque vectoring drive).