An exemplary system may include a gas turbine engine configured to operate at an engine power level to satisfy an engine power demand. The system may also include at least one generator operatively coupled to the engine and configured to generate electrical power based at least in part on the engine power demand. The system further may include at least one heating element in communication with the at least one generator, and at least one control unit coupled to the at least one heating element. The at least one heating element may be configured to receive electrical power from the at least one generator to generate thermal energy. The at least one control unit may be configured to energize the heating element when the engine power demand is below the engine power level and/or there is an anticipated increase in the engine power demand.

The invention relates to a vehicle electrical system that includes a first energy accumulator which has a first maximum open circuit voltage when the first energy accumulator is fully charged, and a second energy accumulator which has a second maximum open-circuit voltage when the second energy accumulator is fully charged. The second maximum open circuit voltage is higher than the first maximum open circuit voltage. The vehicle electrical system also includes a generator configured to generate electrical energy for the vehicle electrical system and a control unit that is configured to detect a recuperation mode of the vehicle. The control unit is also configured to cause the generator, while the vehicle is in the recuperation mode, to generate electrical energy with a charge voltage which is in or above a buffer voltage range, wherein the buffer voltage range lies between the first maximum open circuit voltage and the second maximum open circuit voltage.

An uninterruptable power supply (UPS) system for providing power to a load coupled to a utility power source is provided. The UPS system includes a doubly-fed induction generator (DFIG), a rechargeable energy storage system, a first inverter, and a controller in communication with the DFIG and the first inverter. The DFIG includes a stator and a rotor coupled to the load. The stator and rotor are magnetically coupled together. The DFIG generates an auxiliary power output. The first inverter is coupled between the rotor and the rechargeable energy storage system. The controller detects a power disturbance associated with the utility power source and controls the first inverter to provide an excitation input to the rotor in response to the power disturbance. The DFIG provides the auxiliary power output to the load based on the excitation input.

A method for operating an energy supply unit for a motor vehicle electrical system, including at least one first subsystem and one second subsystem having different voltage levels, the energy supply unit including an electric machine which is connected via a converter circuit to the first subsystem and the second subsystem. In a first operating mode, a switchable switch element of the converter circuit which connects the converter circuit to the second subsystem is opened, the converter circuit is activated as an inverter circuit and the electric machine is motor or generator operated. In a second operating mode, the switchable switch element of the converter circuit is closed, the converter circuit is activated as a DC-DC converter and the DC-DC conversion takes place between the voltage levels of the first and the second subsystem.

A method for operating an energy supply unit for a motor vehicle electrical system, including at least one first subsystem and one second subsystem having different voltage levels, the energy supply unit including an electric machine which is connected via a converter circuit to the first subsystem and the second subsystem. In a first operating mode, a switchable switch element of the converter circuit which connects the converter circuit to the second subsystem is opened, the converter circuit is activated as an inverter circuit and the electric machine is motor or generator operated. In a second operating mode, the switchable switch element of the converter circuit is closed, the converter circuit is activated as a DC-DC converter and the DC-DC conversion takes place between the voltage levels of the first and the second subsystem.

A generator system configured to be connected in parallel with other generators is disclosed. The generator system includes an alternator having a stator with an output winding and a quadrature winding and a rotor with a three-phase winding. The rotor of the alternator is rotatably driven by an engine having a controller to regulate the engine speed. An inverter receives power from the quadrature winding and generates an AC voltage for the rotor winding. The inverter receives an input corresponding to the voltage on the output winding of the stator and also receives an input corresponding to the phase angle of a second AC voltage produced by another power source. The inverter controls the frequency of the AC voltage for the rotor winding such that the phase angle of the voltage on the output winding of the stator is synchronized to the phase angle of the second AC voltage.

The present subject matter is directed to a system and method for operating an electrical power circuit connected to a power grid. The electrical power circuit has a power converter electrically coupled to a generator. The method includes monitoring a rotor speed of the generator during operation of the electrical power circuit. The method also includes increasing an operating range of the rotor speed of the generator. Further, the method includes determining at least one of a line-side voltage of a line-side converter of the power converter or a rotor-side voltage of a rotor-side converter of the power converter during operation of the electrical power circuit. Another step include controlling, via a converter controller, a DC link voltage of a DC link of the power converter as a function of one or more of the line-side voltage, the rotor-side voltage, and/or the rotor speed.

A standby generator includes a standby housing defining a cavity and an internal combustion engine. The engine includes an engine block including a cylinder comprising a piston, an engine housing at least partially covering the engine block, and a crankshaft configured to rotate about a vertical crankshaft axis in response to movement by the piston. The standby generator also includes an alternator configured to generate alternating current electrical power, a controller comprising a rectifier configured to convert the alternating current to a direct current and an inverter configured to convert the direct current to a clean alternating current electrical power, and a transfer switch configured to receive the clean alternating current electrical power from the controller and at least one of grid, solar, or battery power, and configured to supply power to an electrical load. The internal combustion engine, the alternator, and the controller are positioned within the cavity.

A standby generator includes a standby housing defining a cavity and an internal combustion engine. The engine includes an engine block including a cylinder comprising a piston, an engine housing at least partially covering the engine block, and a crankshaft configured to rotate about a vertical crankshaft axis in response to movement by the piston. The standby generator also includes an alternator configured to generate alternating current electrical power, a controller comprising a rectifier configured to convert the alternating current to a direct current and an inverter configured to convert the direct current to a clean alternating current electrical power, and a transfer switch configured to receive the clean alternating current electrical power from the controller and at least one of grid, solar, or battery power, and configured to supply power to an electrical load. The internal combustion engine, the alternator, and the controller are positioned within the cavity.

A doubly-fed induction generator (DFIG) system (100) is described. The DFIG system (100) includes an induction electric machine (102) including a stator having a stator winding and a rotor having a rotor winding. The stator winding is electrically connected to at least one output terminal (108) and the rotor winding is electrically connected to the at least one output terminal (108) by means of a power converter. The power converter includes a first active rectifier/inverter (130a) with alternating current AC terminals electrically connected to the rotor winding, and direct current DC terminals, and a second active rectifier/inverter (136a) with DC terminals electrically connected to the DC terminals of the first active rectifier/inverter by a DC link (138a), and AC terminals electrically connected to the at least one output terminal (108). A controller is adapted to control the first active rectifier/inverter (130a) so that the frequency of the AC current at its AC terminals is substantially constant during at least one of a “line charging mode” and an “islanded mode”.