An off-grid power generating apparatus is provided. The apparatus includes an engine, an alternator and an excitation control device. The alternator includes a rotor, a switch and a stator. The switch is movable between a first position and a second position. An output portion of the stator has first and second segments each of which has at least one coil. The first and second segments are operatively and separately connected with the switch. The first and second segments are connected in series at the first position and in parallel at the second position to provide a high voltage and a low voltage respectively. The excitation control device controls the output voltage to make it have a predetermined frequency, and to regulate the engine speed in response to the load power of the engine.

A system and method of operating a pumped storage power plant using a double fed induction machine with a frequency converter in a rotor circuit is disclosed. A current target value for the rotor current frequency is determined based on a target power to be transmitted between an electrical grid and the double fed induction machine depending on measured actual operating variables. A current inadmissible synchronous deadband is determined depending on variables characterizing a current state of the pumped storage power plant. The synchronous deadband is determined by a permissible minimum required rotor current frequency or speed difference of the rotor speed from the synchronous speed for the stationary operation. The converter is controlled to generate voltages and currents with the current target value of the rotor current frequency if the current target value of the rotor current frequency or speed does not fall in the current inadmissible synchronous deadband.

Embodiments of a method, controller and system include an electric generating system with interleaved direct current DC-DC converter are provided. The embodiments include a controller, a permanent magnet generator (PMG), wherein the PMG provides a 6-phase PMG, and a rectification stage coupled to the PMG. The embodiments also include a boost converter stage coupled to the rectification stage, wherein the boost converter stage comprises four phases, a DC link capacitor coupled to the boost converter stage, and an output filtering stage coupled to the DC link capacitor.

A power generating apparatus is provided. The alternator includes a rotor, a stator, one or more sensors and an electrical circuit. The rotor includes a plurality of symmetric phase windings while the stator has a single phase winding. The excitation control device is configured to control the induced voltage generated in the stator by regulating the rotating magnetic field generated in the phase windings of the rotor. The excitation control device is also configured to regulate the engine speed responsive to calculated load power. The electrical circuit connects the single phase winding of the stator and the load and is configured in a way that the induced voltage generated in the single phase winding and the output voltage applied to the load are at the same frequency. This arrangement reduces costs of the apparatus.

A method and system for providing voltage ripple compensation in a DC power generation system. The system includes a permanent magnet generator (PMG) and a passive rectifier in operable communication with the PMG. The system also includes a boost converter in operable communication with the passive rectifier and a controller in electrical communication with the boost converter. The controller is configured to cause the boost converter to supply a DC bus and to control the boost converter based on a voltage compensation signal to the boost converter to reduce voltage ripple on the voltage of the DC bus.

In accordance with at least one aspect of this disclosure, a method can include measuring a voltage across a DC link of a generator system when a generator exciter is inactive and a generator permanent magnet is active, and detecting a short or open permanent magnet generator (SOPMG) fault condition in the generator system with a DC link monitor operatively connected to measure the voltage across the DC link.

A power generating apparatus is provided. The alternator includes a rotor, a stator, one or more sensors and an electrical circuit. The rotor includes a plurality of symmetric phase windings while the stator has a single phase winding. The excitation control device is configured to control the induced voltage generated in stator by regulating the rotating magnetic field generated in the phase windings of the rotor. The excitation control device is also configured to regulate the engine speed responsive to calculated load power. The electrical circuit connecting the single phase winding of the stator and the load is configured in a way that the induced voltage generated in the single phase winding and the output voltage applied to the load are at the same frequency. This arrangement reduces costs of the apparatus.

To provide a generator controller can determine permission of power generation autonomously within a range where startability is not deteriorated, even in the case where the generator controller cannot communicate with the engine controller. A generator controller, in case of communication normal time with engine controller, permits the generation voltage control when the permission command signal is received from the engine controller and the generator rotational speed is higher than a determination value at communication normal time, and prohibits the generation voltage control at other times; in the case of communication failure time, permits the generation voltage control when the generator rotational speed is higher than a determination value at communication failure time, and prohibits the generation voltage control at other times.

A rectifier and a vehicle AC generator that can suppress the cost, the rectification loss, and the leakage current from increasing are provided. A rectifier is configured in such a way that in each of n sets, one of a positive electrode side semiconductor device and a negative electrode side semiconductor device is a MOSFET, in such a way that in at least one of the n sets, the other one of the positive electrode side semiconductor device and the negative electrode side semiconductor device is a specific diode, and in such a way that the specific diode is a Schottky barrier diode or a MOS diode, which is a MOSFET whose drain terminal and gate terminal are short-circuited.

A power apparatus for a vehicle manages power for a vehicle by performing a power-up operation according to a power-up method determined on the basis of a voltage formed at a power input node connected to a battery of the vehicle when a power-up signal is applied. The power apparatus including a regulator configured to regulate a battery voltage inputted through the power input node; a switch driving circuit configured to turn on/off a switch that controls a connection between the battery and the regulator through the power input node; and a main logic circuit configured to receive control authority for the switch driving circuit from the power apparatus when receiving the power-up signal and the operating voltage generated by the regulator, and to control an on/off operation of the switch.