Abstract: The present application provides a method and device for controlling a generator-side terminal voltage of a converter, and a controller of the converter. The method includes: determining an upper limit of the generator-side terminal voltage based on a present voltage value of a direct-current (DC) bus of the converter, where the generator-side terminal voltage is a voltage of an output terminal of a generator, and the output terminal is connected to the converter; determining an optimal value of the generator-side terminal voltage that minimizes a present value of a generator-side current, where the generator-side current is a current of the output terminal of the generator; setting a target value of the generator-side terminal voltage based on the upper limit and the optimal value of the generator-side terminal voltage. The target value includes a control reference value of the generator-side terminal voltage.

Abstract: An aircraft includes a fuselage, a main wing, and a flight controller. The main wing is attached to the fuselage and configured to generate lift that acts on the aircraft. The flight controller includes an electric field direction estimator, an attitude calculator, and an attitude controller. The electric field direction estimator is configured to estimate a direction of an electric field around the aircraft. The attitude calculator is configured to calculate a target airframe attitude that reduces a possibility of occurrence of lightning strike on the aircraft, on the basis of the direction of the electric field estimated by the electric field direction estimator. The attitude controller is configured to control an attitude of an airframe of the aircraft to cause the attitude of the airframe to be the target airframe attitude calculated by the attitude calculator.

Abstract: 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.

Abstract: A wind turbine comprising a converter connected to a generator, which converter supplies at least some of the energy generated by the electrical generator into an electrical grid, sensors for interference in the electrical grid and a controller module for controlling the converter and/or the wind turbine. The controller module comprises a grid interference module which, in the case of detected interference in the electrical grid, counteracts the interference. The controller module comprises an override module which, in the case of a detected interference in the grid, is provided in order to deactivate the grid interference module at least in part. This improves the behavior in interference situations in that the controller module detects, over the course of the interference, that at least parts of the inherent grid stabilization functions do not counteract the interference and, in this specific situation, it deactivates the respective harmful grid stabilization functions.

Abstract: An energy storage and delivery system includes an elevator operable to move blocks from a lower elevation to a higher elevation to store energy and from a higher elevation to a lower elevation to generate electricity. A winch assembly is movably coupled to a cable that is coupled to the elevator. The winch assembly has planetary gear assemblies, brakes that selectively engage at least a portion of the planetary gear assemblies, and a spool coupled to the cable. A drive shaft extends between a motor-generator and the winch assembly. A brake is operable so that the spool rotates to reel-in the cable to raise the elevator to move a block from a lower elevation to a higher elevation to store energy or so that the spool rotates to reel-out the cable to lower the elevator to move a block from a higher elevation to a lower elevation to generate electricity.

Abstract: Provided is a method for controlling a wind power system, that is to say a wind power installation or a wind farm comprising a plurality of installations, for feeding electrical power from wind into an electrical supply grid, and for damping low-frequency oscillations, in particular subsynchronous resonances, in the grid, wherein the grid has a line voltage with a nominal line frequency, wherein a damping control with a closed control circuit is used for damping the low-frequency oscillations, and the damping control for damping the low-frequency oscillations controls a feed-in of electrical power into the grid using a wind system control, the damping control is designed for a controlled system comprising the grid, the wind power system, and the wind system control, or parts thereof, wherein the damping control is designed such that it prevents and/or damps weakly damped modes in the closed control circuit.

Abstract: Provided is a method for feeding electrical power into an electrical supply network using a converter-controlled infeed apparatus. The apparatus feeds into a local network section of the electrical supply network at a network connection point. The network has further infeed apparatuses and consumers for consuming electrical power. The local section has a ratio of power able to be fed in using converters to a total power able to be fed in by all infeed apparatuses of at least 50%. A controller controls the infeed of the electrical power depending on a network state of the network. The controller has control behavior that depends on a network characteristic of the local section. The network characteristic is dependent on at least one property of the local section and at least one property of a further network section of the network or a determination that no further network section is present.

Abstract: A hydroelectric power generation system is included in a channel control system. The channel control system includes a command section that outputs a command value of a flow rate or pressure of a fluid, an opening degree control unit that calculates a target opening degree based on the command value, and a motor-operated valve installed in a channel through which the fluid flows. The valve opens and closes in accordance with the target opening degree. The hydroelectric power generation system includes a water turbine disposed in the channel, a generator driven by the water turbine, and a generator control unit that controls at least one of a torque and a number of rotations of the generator based on opening degree information that indicates a measured value of an actual opening degree of the valve or an opening degree estimated.

Abstract: The present disclosure relates to a method for operating a converter on a three-phase electrical power supply grid, comprising the following steps: operating the converter in a first operating mode by means of a control unit for generating an output current, wherein the converter in the first operating mode operates in such a way as to apply a voltage to the electrical power supply grid; detecting a grid fault on the electrical power supply grid by means of a detection means during the first operating mode; limiting the output current of the converter by means of current limitation when a grid fault on the electrical power supply grid has been detected during the first operating mode, in particular in such a way that the output current of the converter falls below a predetermined maximum current or substantially corresponds thereto.

Abstract: Disclosed herein are systems and methods for generating energy from a container configured to be fully submerged in a liquid and containing differing volumes of gas in order to alternatively ascend and descend through the liquid in order to rotate a drum spool connected to the container by a cable hose that unwinds from the drum spool as the container ascends, and winds as the cable descends. The rotational energy of the drum spool may thus be harvested.

Abstract: A method for providing grid-forming control of an inverter-based resource includes receiving, via a controller, a power reference signal. The method also includes determining a dynamic power change limit. Further, the method includes determining, via the controller, an upper power boundary and a lower power boundary for grid-induced power deviations from a desired power operating point based on the power reference signal. Moreover, the method includes determining, via the controller, limits for an inertial power regulator reference based, at least in part, on the upper and lower power boundaries and the dynamic power change limit. In addition, the method includes applying, via the controller, the limits to the inertial power regulator reference in an inertial power regulator of the inverter-based resource.

Abstract: A wave energy conversion device includes a permanent magnet generator, a first driving component and a second driving component. The permanent magnet generator includes a stator structure and a rotor structure. The stator structure includes a stator body. The rotor structure includes a rotor body. The rotor body is disposed inside the stator body in a swinging manner or in a rotatable manner. The first driving component is coupled to the rotor structure. The second driving component is coupled to the stator structure. The wave energy conversion device of the present invention requires a low speed/angle of a swinging/rotating movement of the rotor body relative to the stator body to generate electricity, which facilitates electricity generation from wave energy.

Abstract: An internal combustion engine system includes an internal combustion engine having a cylinder, an air intake system to feed air to the cylinder, an exhaust gas system to feed exhaust gas away from the cylinder, a turbocharger including a turbocharger turbine operatively connected to a turbocharger compressor, wherein the air intake system is arranged to feed intake air via the turbocharger compressor and wherein the exhaust gas system is arranged to feed exhaust gas via the turbocharger turbine so as to drive the turbocharger compressor, and wherein the internal combustion engine system further includes a positive displacement machine arranged in the exhaust gas system downstream of the turbocharger turbine. The internal combustion engine system further includes a variable drive unit to drive the positive displacement machine. The internal combustion engine system controls the drive unit so as to control a flow of exhaust gas through the positive displacement machine.

Abstract: The invention relates to a method for determining the energy production to be expected for a wind power installation for a forecast time period, which may be an expected annual energy production. The installation has installation components. In the method, at least one of the installation components is selected as a thermally relevant component and chronologically distributed wind speed values are specified for the forecast time period. An expected power output level of the installation is determined for one of the wind speed values. In the power output level determining step, a component temperature which is assigned to this wind speed value is taken into account by the at least one thermally relevant component. The expected power output level of the installation, which is determined for the wind speed value, is used to determine the energy production of the installation which is to be expected for the forecast time period.

Abstract: A wave power harnessing device which may include a base configured to support at least one guide opening; first and second shafts which may be situated apart and parallel from each other and to the base; first and second sprockets coupled to the first and second shafts, respectively, the first and second sprockets may each include an overrunning clutch configured to rotate the shaft coupled thereto in a single direction; a force transmitting member (FTM) may be coupled to the first and second sprockets; at least one buoy drive shaft (BUDS) may be coupled to the FTM and to at least one buoy; and/or a generator coupled to at least one of the first and second shafts and which may be configured to generate an electrical power.

Abstract: The present application provides a method and a system for controlling continuous low voltage ride-through and high voltage ride-through of a permanent magnet direct-driven wind turbine. The method includes: determining a transient time period during which the wind turbine is transitioned from a low voltage ride-through state to a high voltage ride-through state; controlling the wind turbine to provide, during the transient time period, a gradually increasing active current to the point of common coupling; and controlling the wind turbine to provide, during the transient time period, a reactive current to the point of common coupling according to an operation state of the wind turbine before the low voltage ride-through state.

Abstract: An electricity generator includes a wind tunnel positioned on the vehicle. The wind tunnel has an open first end and an open second end. The open first end is in communication with ambient air. A turbine chamber is fluidly coupled to the open second end of the wind tunnel. At least one wind turbine is positioned in the turbine chamber. The at least one wind turbine includes a housing. A rotor is positioned in the housing along an axis that is substantially perpendicular to an axis of the wind tunnel.

Abstract: The present disclosure provides a high-frequency uncontrolled rectifier-based DC transmission system for an offshore wind farm, including a DC system and an offshore AC system. The offshore AC system mainly includes wind turbines based on permanent magnet synchronous generators with full-scale power converters, AC submarine cables, and offshore step-up stations. The DC system includes an offshore station and an onshore station that are connected by DC submarine cables, where a converter of the offshore is a three-phase six-pulse uncontrolled rectifier bridge, while a converter of the onshore station is MMC. Each of the offshore AC system and the offshore station has a rated frequency far above 50 Hz, which can usually be chosen to be in a range of about 100 Hz to 400 Hz. The disclosed transmission system allows for a great reduction in construction costs and demonstrating great application potentials in actual engineering.

Abstract: A system for extracting work from the expansion of a working fluid includes a vessel having at least a portion of the working fluid, a heating device in thermal communication with the portion of the working fluid in the vessel for heating the portion of the working fluid in the vessel and expanding the working fluid, and a conversion tool. The conversion tool is in fluid communication with the vessel and is configured to receive working fluid from the vessel when the working fluid expands. The conversion tool is further configured to extract work from the expanded working fluid.

Abstract: A system for extracting work from the expansion of a working fluid includes a vessel having at least a portion of the working fluid, a heating device in thermal communication with the portion of the working fluid in the vessel for heating the portion of the working fluid in the vessel and expanding the working fluid, and a conversion tool. The conversion tool is in fluid communication with the vessel and is configured to receive working fluid from the vessel when the working fluid expands. The conversion tool is further configured to extract work from the expanded working fluid.