A control apparatus controls an inverter which outputs electric power to an electric motor. The control apparatus determines which one of a one-pulse control and a pulse-width modulation control is employed as a control method of the inverter in accordance with a predetermined condition based on an electric motor drive torque of the electric motor, a rotation number of the electric motor, and a DC voltage of the electric motor.

A method for controlling the activation of an electric machine in voltage control mode for an electrical network of a motor vehicle following a failure of a traction battery present in a traction network of the vehicle. The traction network includes the traction battery, the electric machine, an inverter and a DC-to-DC converter connecting the traction battery to an onboard network of said motor vehicle. The method includes a step of precharging capacitors present in the electrical network and a step of activating the electric machine in voltage control mode for the electrical network. The activation of the electric machine in voltage control mode is activated before the deactivation of precharging.

A method for operating a permanent magnet synchronous motor comprises setting a maximum power, determining a current vector and an output voltage vector in the dq coordinate system. A setpoint amount for a setpoint voltage vector is calculated on the basis of the maximum power, the current vector and the output voltage vector. The setpoint voltage vector is generated with the setpoint amount, and then operating the permanent magnet synchronous motor at least with the setpoint voltage vector.

The invention relates to a method for controlling an inverter which is electrically connected to an electric motor, having the following steps: defining a modulated voltage (S1) for the inverter, said voltage being based on a first switching frequency, for operating the electric motor with a current, wherein the current has an electric frequency; determining the electric frequency (S2); changing the first switching frequency (S4) on which the modulated voltage is based to a second switching frequency if a value pair consisting of electric frequency and first switching frequency, or a value pair consisting of electric frequency and a sideband of the first switching frequency, is within at least one defined disturbance range (S3).

Lightweight, energy-dense, high-efficiency, hybrid power systems for electric aircraft including a prime mover internal combustion engine or gas turbine coupled to a self-cooling polyphase axial-flux dual-Halbach-array motor/alternator where the number of phases N.sub.phase is greater than or equal to three. The motor/alternator is connected to a regenerative power converter drive also having N.sub.phase phases, which, in turn, is connected to a DC power bus, a battery, a battery management system, and a system controller. In some embodiments, the motor/alternator and regenerative power converter drive have a neutral connection.

A vehicle control apparatus for an electric vehicle including a battery and a motor includes a traveling controller. The traveling controller drives the motor on the basis of a carrier frequency to control a driving force of the electric vehicle and to cause the electric vehicle to travel, and changes the carrier frequency on the basis of a speed ratio set through a shift operation performed by a driver of the electric vehicle.

Methods and system are described for estimating an amount of battery usage for a traction battery of a vehicle. The traction battery usage estimate may be based on or a function of a distance per gallon of gasoline-equivalent so that the usage estimate may be more familiar to vehicle operators. In addition, the traction battery usage estimate may also be based on traction battery current and traction battery voltage.

A method for a safety concept for an AC battery, in which the AC battery includes a central controller, a plurality of battery modules which respectively have a power board with a plurality of switching states, a plurality of contactors, a plurality of current sensors, a fault loop and a high-speed bus and is connected to a traction machine. The central controller has a hardware-programmable processor unit with at least one microprocessor core on which a control program is configured to control the battery modules, the plurality of contactors and the fault loop. A state machine is implemented by the control program. The battery modules are connected, starting from the central controller, via the high-speed bus and the fault loop. If an abort fault occurs, the AC battery is changed to a safe operating state. The safe state is achieved at least by emergency disconnection of the central controller.

An electric rolling stock control device includes a voltage controlling unit for controlling an output voltage of an inverter and a speed estimating unit for calculating a rotation speed estimation value of an electric motor. The speed estimating unit includes an initial speed estimating unit for outputting an initial speed estimation value, a steady speed estimating unit for outputting a steady speed estimation value, a correction coefficient calculating unit for calculating a correction coefficient based on the steady speed estimation value and a backup speed, and a correction speed calculating unit for storing the correction coefficient in a storage unit and calculating a correction speed by multiplying the correction coefficient by the backup speed.

A vehicle, in particular to a rail vehicle, has at least one drive motor and a brake control device. A monitoring device measures, in the braking mode of the vehicle, at least one drive current which flows through the drive motor, and at least one drive voltage which is applied to the drive motor, to form measured values, and to generate operational information which specifies the mode of operation of the drive motor, in particular braking information which specifies a braking effect of the drive motor, on the basis of the measured values.