A vehicle includes a traction battery, an electric machine, and a variable voltage converter. The variable voltage converter includes an inductor and is disposed electrically between the traction battery and electric machine. The vehicle also includes a controller programmed to issue duty cycle commands for the variable voltage converter based on a product of an AC component of current flowing through the inductor and a calibrated resistance.

An overvoltage protection circuit for a first subsystem of a multivoltage vehicle electrical system, in which the first subsystem having a first vehicle electrical system voltage, a second subsystem having a second vehicle electrical system voltage, and an electric machine for supplying the second subsystem. The first system voltage is less than the second system voltage. The overvoltage protection circuit includes a first ground connection for connecting a shared ground potential of the first subsystem, the second subsystem, and the electric machine, an additional second ground connection for connecting a reference ground potential, and a control connection for controlling the electric machine. The overvoltage protection circuit checks whether a ground differential voltage between the first and second ground connections reaches a threshold value, and for reducing the second vehicle electrical system voltage when the ground differential voltage between the first and second ground connections reaches the threshold value.

A vehicle powertrain includes a bypass diode and a controller. The bypass diode is configured to clamp an inverter DC terminal voltage to a battery voltage. The controller is configured to, while the terminal voltage is within a predetermined range of the battery voltage, maintain off a lower IGBT of a DC-DC converter while in a propulsion mode, and modulate the lower IGBT to increase the terminal voltage to maintain the bypass diode reverse biased while in a regenerative mode.

A closed-loop system may include a plant (an elctric machine requiring control) and a fractional-order proportional-resonant controller. The fractional-order proportional-resonant controller may have an order greater than zero and less than or equal to one. The order for the fractional-order proportional-resonant controller may be selected to yield a target amplitude and target slope for frequency response. The frequency response may be such that a steady-state error associated with a speed of the electric machine is inversely proportional to the target amplitude and less than a predetermined threshold. The order of the controller may be 0.9.

A mounting device is provided for oscillatingly mounting a range extender, which consists of an internal combustion engine and a generator, on a body and/or a chassis of a motor vehicle by way of vibration-damping elements. At least two of the vibration-damping elements are integrated in load-carrying bearings and one additional one is integrated in a supporting bearing for supporting moments. The mounting device is characterized in that the vibration-damping elements of the mounting device at least for the load-carrying bearings are secured to the range extender, i.e. a first vibration-damping element is secured to the internal combustion engine and a second vibration-damping element is secured to the generator.

Methods and systems are provided related to a self-propelling work machine in the form of a tracked vehicle having an electric drive, with a generator drivable by an internal combustion engine, an auxiliary unit connected to the engine, and a braking apparatus for braking the work machine. The braking apparatus provides regenerative braking by the electric drive and comprises a feedback apparatus for feeding back electrical motor braking power of the electric motor to the generator to apply the motor braking power on the engine and on the auxiliary unit. A controller automatically increases or decreases the electrical load of the auxiliary unit based on the electrical motor braking power fed back to the engine and/or based on an engine speed.

An electronic control unit (ECU) including non-transitory instructions executable to set a threshold as a shutdown threshold when, during a power supply operation, a duration of a power supply stoppage exceeds a first time; stop an operation of an engine or prohibit the engine from operating; and executing system shutdown processing when an SOC of a storage apparatus falls to or below the shutdown threshold or the duration of the power supply stoppage exceeds a second time.

A power converter has a series direct connection mode of keeping on/off of a plurality of switching elements to maintain the state where first and second DC power supplies different in amount of voltage change with respect to input/output of the same amount of electric power are connected in series with an electric power line connected to a load, and a voltage controlling mode of controlling an output voltage on the electric power line to be a voltage command value by controlling on/off of the plurality of switching elements. In the voltage controlling mode, between time tx and ta, the sum of voltages of the first and second DC power supplies is matched with the voltage command value by controlling the output voltage by means of charging/discharging between the first and second DC power supplies. After time ta, the series direct connection mode is applied.

An electric power system of a vehicle with electric propulsion having: an electric machine; a storage system provided with two chemical battery packs electrically separated from each other; an electronic DC/AC power converter, which exchanges electric energy with the storage system and controls the electric machine; a pair of electronic DC/DC power converters, each of which increases the voltage and has a low-voltage side, which is electrically connected only and exclusively to a corresponding chemical battery, and a high-voltage side, which is connected to the electronic DC/AC power converter in parallel to the high-voltage side of the other electronic DC/DC power converter; and a common container, which houses the storage system and the electronic power converters therein.

A method for operating an electric machine with a power source and with an electric motor and with an intermediary power converter, wherein an input current of the power source is converted into a multi-phase output current for the electric motor by means of a pulse width modulated control of a plurality of semiconductor switches of the converter, wherein during each period of control, for at least one phase, a pulse with a pulse duration is generated during a period duration, wherein in a period, a pulse is divided into a leading first half-pulse and a trailing second half-pulse with in each case half a pulse duration, and wherein the first half-pulse with a first displacement time and the second half-pulse with a second displacement time are mutually shifted in time within the period duration of the period.