Abstract: A multi-buffer energy accumulation apparatus comprises: an energy storage cylinder, an oil tank, a first scroll spring mechanism, a second scroll spring mechanism, a hydraulic motor, differential planetary train of gearings, and a generator; wherein the energy storage cylinder comprises a hermetically sealed cylinder body, one end of the hermetically sealed cylinder body being provided with an elastic mobile device, the other end thereof being provided with an energy transmission device, and hydraulic oil is filled in the hermetically sealed cylinder body between the elastic mobile device and the energy transmission device; the hermetically sealed cylinder body, the hydraulic motor, and the oil tank are connected via an oil circuit to form a hydraulic loop; the energy transmission device is connected with the first scroll mechanism; the hydraulic motor is connected with the second scroll spring mechanism.

Abstract: An electrical machine has a stator with windings, first and second rotors, and an electrical output regulator. The first rotor carries alternating polarity first field magnets, such that, on drive mechanism rotation, the windings interact with the magnetic flux produced by the first magnets to create an EMF. The second rotor carries alternating polarity second field magnets, and has first and second rotational positions to reduce and increase, respectively, the magnetic flux energy. The electrical output regulator regulates a current from the windings to produce a torque on the rotors, as the drive mechanism increases from zero rotational speed, the torque rises above a threshold level that moves the second rotor from the first to the second rotational position, and, as the drive mechanism further increases the rotational speed, the torque peaks and then drops below the threshold level to move the second rotor back to the first rotational position.

Abstract: The invention relates to a device for recovering wave energy, the device including a drum which is adapted to rotate around its centre axis and inside which an electric generator is adapted, arranged to be rotated by the rotating motion of said drum. In order for the device to recover energy better than prior art devices, the device includes at least one wing adapted on the outside of the drum, the wing being arranged to turn in such a way that it may be turned from a first position to a second position whereby, as the wing is in its first position, the motion of water in a first direction of the drum centre axis is arranged to rotate the drum in a first direction, and as the wing is in its second position, the motion of water in a second direction of the drum centre axis is also arranged to rotate the drum in said first direction, and the turning of the wing is arranged to take place under control of a pressure sensor.

Abstract: Provided are a control method and system for enhancing an endurance capability to an abnormal voltage of a wind turbine generator system. The control method, includes; providing a doubly-fed wind turbine generator system connected to a power grid; detecting a voltage of the power grid, and determining whether the voltage of the power grid has a fault; when the voltage of the power grid has a fault, detecting a voltage of the DC buses, and determining whether the voltage of the DC buses exceeds a limit value; when the voltage of the DC buses exceeds the limit value, performing integrated system coordination control according to an abnormal operating condition mode; and when the voltage of the power grid returns to a normal range, performing integrated system coordination control according to a normal operating condition mode.

Abstract: A method for operating an electrical power system includes detecting a bridge current magnitude in a rotor-side converter or line-side converter of a power converter, the power converter electrically coupled between a generator rotor and a transformer. The method further includes comparing the bridge current magnitude in the one of the rotor-side converter or line-side converter to a primary predetermined threshold. The method further includes disabling bridge switching of one of the rotor-side converter or line-side converter when the bridge current magnitude exceeds the primary predetermined threshold.

Abstract: A system includes one or more synchronous generators and one or more corresponding exciters. The exciter is configured to output a field current for exciting the synchronous generator to produce a voltage and a current at an output of the synchronous generator. The system may also include one or more electric motors electrically coupled to the synchronous generator and configured to drive one or more mechanical loads. A controller included in the system is configured to identify power angle oscillations between the voltage and the current and control an exciter voltage of the exciter to damp the identified power angle oscillations.

Abstract: An apparatus includes a first inverter circuit and a second inverter circuit. The first invertor circuit is configured to couple an alternator and a load device to deliver a driving signal from the alternator to the load device. The second invertor circuit is configured to couple the alternator to the load device to deliver a driving signal from the alternator to the load device and configured to couple a battery to the alternator to deliver a charging signal from the alternator the battery.

Abstract: A water current power generating system includes a support structure located on a bed of a body of water. A power generating apparatus, such as a water current turbine device, is mounted on the support structure, by way of a mounting portion. The system also includes a measurement unit operable to determine operating information relating to operation of the system, and a controller operable to determine loading on the system from such operating information, and to adjust a controlled parameter of the system such that loading on the system falls below a predetermined threshold value.

Abstract: A blade icing state identification method and apparatus for a wind generator set are disclosed. The method includes setting a preset wind speed threshold and a preset rotating speed threshold, and setting the preset rotating speed threshold as a lower limit value of a maximum limited rotating speed of the wind generator set operating under a limited power condition; comparing a current wind speed and a current rotating speed of the wind generator set with the preset thresholds respectively; progressively increasing a blade icing possibility index when the current wind speed is greater than the preset wind speed threshold and the current rotating speed of the wind generator set is smaller than the preset rotating speed threshold, and otherwise, progressively decreasing the blade icing possibility index; and determining that blades are in an icing state when the blade icing possibility index is greater than a preset index.

Abstract: A method for controlling voltage of a DC link of a power converter of an electrical power system connected to a power grid includes operating the DC link to an optimum voltage set point that achieves steady state operation of the power converter. The method also includes monitoring the power grid for one or more transient events that may be an indicator of one or more sub-synchronous control interaction (SSCI) conditions occurring in the electrical power system. Upon detection of the transient event(s) occurring in the power grid, the method also includes immediately increasing the optimum voltage set point to a higher voltage set point of the DC link. Moreover, the method includes operating the DC link at the higher voltage set point until the sub-synchronous control interaction(s) is damped, thereby optimizing voltage control of the DC link.

Abstract: A micro-CHP gas boiler comprises a heat exchanger having a combustion space surrounded by a water flowpath, and a gas turbine assembly which is installed in the combustion space. The gas turbine assembly includes a generator surrounded by an annular combustion chamber and cooled by a water jacket which forms part of the flowpath, and a fuel gas compressor which is integrated into the thrust runner on the turbine rotor shaft between foil air bearings.

Abstract: A control method for increasing reactive power generation of a wind turbine having a Doubly-Fed Induction Generator (DFIG) includes obtaining, by a control device having one or more processors and one or more memory devices, wind forecast data of the wind turbine. Further, the method includes generating, by the control device, a real-time thermal model of the DFIG of the wind turbine using the wind forecast data. More specifically, the thermal model defines a thermal capacity for the DFIG that does not exceed system limits. Thus, the method also includes dynamically adjusting, by the control device, a reactive power set point of the DFIG of the wind turbine based on the real-time thermal model.

Abstract: A power system includes a bus, a first controller and one or more second controllers. The first controller is configured to excite a first generator to generate electric power on the bus in response to initiation of rotation of the first generator. The one or more second controllers are configured to excite one or more respective second generators with a constant excitation in response to initiation of rotation of the first generator. The second generator(s) are electrically coupled with the bus and configured to operate as a motor to commence synchronous rotation with the first generator in response to electric power being present on the bus. The second controller(s) are further configured to initiate dynamic adjustment of the excitation of the second generator(s) to generate electric power on the bus with the second generator(s) in response to the first generator and the second generator(s) synchronously reaching a predetermined rotational speed.

Abstract: A wind power generation system including a doubly fed induction generator (DFIG) of a wind turbine is presented. The DFIG includes a rotor and a stator, a rotor-side conversion unit coupled to the rotor, a direct current (DC) link, and at least one line-side conversion unit coupled to the rotor-side conversion unit via the DC link and coupled to the stator of the DFIG. The at least one line-side conversion unit includes exactly one first converter, high frequency transformers, and second converters, where each of the second converters is coupled to the first converter via a respective high frequency transformer, and inverters, where each of the inverters is coupled to a respective second converter and includes an alternative current (AC) phase terminal.

Abstract: An electrical generator (114) and a power electronics interface (115) for a direct-drive turbine (110). The turbine (110) may include a rotor (112) for transforming kinetic (from, e.g., wind, water, steam) into mechanical energy, the generator (114) for transforming the mechanical into electrical energy, and the power electronics interface (115) for conditioning the electrical energy for delivery to a power distribution grid (124). The interface (115) includes a three-phase single-stage boost inverter (120) for converting a lower DC voltage into a higher AC voltage, and which uses a synchronous reactance of the generator (114) as a DC-link inductance. The turbine (110) has neither the gearbox of indirect-drive designs nor the electrolytic capacitor bank of conventional direct-drive designs, while still allowing for a substantially smaller number of generator poles, resulting in reduced size, weight, complexity, and cost.

Abstract: An engine generator, including an engine having a piston reciprocating inside a cylinder, a generator unit having a three-phase winding, driven by the engine to generate power and operating as an engine starter motor during engine starting, a power converter circuit connected to the generator unit, a battery supplying power to the generator unit through the power converter circuit during engine starting, an engine speed detection unit detecting an engine speed, a connection switching unit switching a connection configuration of the winding to one of a wye-connection and a delta-connection, and a connection switching control unit controlling the connection switching unit to switch the connection configuration to the wye-connection when the engine speed is lower than a predetermined engine speed, and to switch the connection configuration to the delta-connection when the engine speed is equal to or higher than the predetermined engine speed, during engine starting.

Abstract: An air-driven generator for generating electric power from movement of a working fluid. Upper ends of buoyancy conduits are in fluidic communication with an upper end of a gravitational distribution conduit, and a lower end of the gravitational distribution conduit is in fluidic communication with lower ends of the buoyancy conduits. An air injection system injects air into the buoyancy conduits. A closed fluid loop is formed with working fluid flowing from the gravitational distribution conduit driving a fluid turbine system that is interposed between the lower ends of the gravitational distribution conduit and the buoyancy conduits. Flow of working fluid can be induced by an injection of air into working fluid disposed in the buoyancy conduits to achieve a generation of power by actuation of the fluid turbine system. An upper chamber can remove entrained air. A Rankin Cycle Generator can receive and be actuated by exhausted air.

Abstract: A system may include a prime mover configured to provide mechanical energy to the system by spinning a shaft. The system further includes a synchronous AC generator mechanically coupled to the shaft, and an exciter mechanically coupled to the shaft and configured to output a field current for exciting the synchronous AC generator. The system also includes a number of synchronous electric motors electrically coupled to the AC generator and configured to drive one or more mechanical loads. A controller of the system is configured to establish and maintain a magnetic coupling between the synchronous AC generator and the synchronous electric motors by controlling a level of the field current during a ramped increase in rotation of the synchronous AC generator from zero rotational speed. The motors accelerate synchronously with the generator due to the magnetic coupling as the rotational speed of the generator increases.

Abstract: A converting device arranged to transfer thermodynamic energy of a compressed working fluid into electrical energy. The converting unit is comprised of at least one cylinder which encloses a piston. In an embodiment, said at least one piston is provided with a magnetic portion. A ferromagnetic coil surrounds the piston and is integrated with the cylinder. As the piston moves through the coil, electrical energy is generated.

Abstract: A motor vehicle comprises a motor configured to input and output power for driving; an inverter configured to drive the motor; a power storage device configured to transmit electric power to and from the motor; a system main relay configured to connect and disconnect the power storage device with and from a power line on an inverter-side; and a control device configured to enable the motor vehicle to be driven with turning on the system main relay according to a predetermined procedure in response to a system on-operation. The motor vehicle does not perform failure diagnosis of the inverter when an abnormality signal of the inverter is generated before a predetermined time after the system main relay is turned on in response to the system on-operation, while performing the failure diagnosis when the abnormality signal of the inverter is generated after the predetermined time.