An electrical power supply system, in particular for a microgrid, includes a DC bus, and a first rectifier and a second rectifier, with the first and second rectifiers each supplying power to the DC bus. The first rectifier is a diode rectifier and the second rectifier has switchable power semiconductors. The electrical power supply system further includes a generator supplying power to both rectifiers. The rectifiers can be connected at different times according to a load.

An actuating device of a pump of a fuel pumping system of an engine, including a motor, a generator, an inverter, a switching member and a control member, the motor including a first rotor coupled to the pump and a first stator including at least one input stator winding, the generator including a second rotor coupled to a drive shaft of the engine, and a second stator including at least one output stator winding, the control member being configured to control the switching member in order to selectively connect each input stator winding: to a corresponding output stator winding if a speed of the engine is higher than or equal to a predetermined speed; to a corresponding output of the inverter, otherwise.

An uninterruptible power supply system has a regulated power source, an electrical generator electrically interconnected to the regulated power source, an engine having a main shaft integral with or coupled to the shaft of the electrical generator, a rotating rectifier mounted onto a shaft of the electrical generator, a mains power supply, a switch connected between the electrical generator, the mains power supply and a synchronous machine of the regulated power source, a synchronous generator, and an uninterruptible load. The regulated power source has a housing, a synchronous machine, a synchronous generator, and a flywheel sharing a common shaft. The electrical generator has a shaft coupled to a combustion engine. The switch transfers power from the synchronous machine to the electrical generator to cause the electrical generator to rotate its shaft or the main shaft of the engine. A short-stop load is supplied power from the electrical generator.

Exhaust gases from an engine, input to turbo-compounder, drive a bladed turbine rotor therein, which drives a multi-phase AC generator, the output of which is used to electrically drive a multi-phase induction motor, the rotor of which is mechanically coupled to the engine, so as to provide for recovering power to the engine. The multi-phase AC generator may be coupled to the engine either by closure of a contactor, engagement of an electrically-controlled clutch, or by control of either a solid-state switching or control system or an AC excitation signal, when the frequency (f.sub.GENERATOR) of the multi-phase AC generator meets or exceeds that (f.sub.MOTOR) of the multi-phase induction motor.

Exhaust gases from an engine, input to turbo-compounder, drive a bladed turbine rotor therein, which drives a multi-phase AC generator, the output of which is used to electrically drive a multi-phase induction motor, the rotor of which is mechanically coupled to the engine, so as to provide for recovering power to the engine. The multi-phase AC generator may be coupled to the engine either by closure of a contactor, engagement of an electrically-controlled clutch, or by control of either a solid-state switching or control system or an AC excitation signal, when the frequency (f.sub.GENERATOR) of the multi-phase AC generator meets or exceeds that (f.sub.MOTOR) of the multi-phase induction motor.

An arrangement contains an asynchronous machine, which, in generator operation, is configured to feed electric power into an AC network. Accordingly, the asynchronous machine can be dual-fed by a modular multi-stage converter in a matrix configuration. The asynchronous machine has a rotor and the modular multi-stage converter is connected to the rotor of the asynchronous machine.

A rotary electric system includes a rotary electric device that includes: a stator including a stator winding; and a rotor. The stator winding includes: a first coil group that generates a rotating magnetic field to rotate the rotor; and a second coil group that generates power with induced electromotive force due to rotation of the rotor.

In a variable speed generator/motor device including a variable frequency power converter, a direct current voltage device including a voltage type self-excited converter, an automatic voltage adjuster, and a converter current adjuster that controls unit converters, a first three-phase branch circuit is provided between the direct current voltage device and an alternating current system; a second three-phase branch circuit is provided between the variable frequency power converter and a three-phase squirrel-cage induction machine; a first load switch is provided between the first three-phase branch circuit and the second three-phase branch circuit; a measurement current transformer is provided between the three-phase squirrel-cage induction machine and the second three-phase branch circuit.

An intelligent electronic device (IED) according to the present disclosure can estimate a full load rotor resistance value as a function of motor positive-sequence resistance. The IED may estimate the full load rotor resistance value by measuring zero-crossings of voltage after a motor disconnect. The IED may also acquire motor current and voltage measurements and calculate motor slip using the acquired motor current and voltage measurements and the estimated full load rotor resistance value.

A system that is directly coupled to the transmission network or the distribution network, wherein a variable-speed, twin-fed asynchronous machine is combined with a flywheel. Besides the function as a voltage-regulating phase shifter, energy in the flywheel can at the same time be stored or removed as the speed changes. The provided properties relate to a combination of frequency support, voltage stabilisation, energy storage and short-circuit capacity. In a particular embodiment the speed of the flywheel is increased in relation to the speed of the rotor by a transmission, wherein the capability of the flywheel to store energy advantageously rises disproportionally with the speed.