Abstract: Provided is a method of estimating a value of wind speed a wind turbine is subjected to, the wind turbine having a rotor with rotor blades at least one having an adaptable flow regulating device installed, the method including: obtaining values for power output of the wind turbine, rotor speed of the rotor, and pitch angle of the rotor blades; obtaining state information of the adaptable flow regulating device; and estimating the value of the wind speed based on the values for power output, rotor speed, pitch angle and the state information of the adaptable flow regulating device.

Abstract: The invention provides a method for controlling a wind turbine. The method predicts behaviour of the wind turbine components for the time stages over a prediction horizon using a wind turbine model describing dynamics of the wind turbine, where the time stages include a first set of time stages from an initial time stage and a second set of time stages subsequent to the first set. The method determines control outputs, e.g. individual blade pitch, for time stages based on the predicted behaviour. The method then transmits a control signal to implement only the control outputs for each of the second set of time stages so as to control the wind turbine. Advantageously, the invention reduces both average and peak computational loads relative to standard predictive control algorithms.

Abstract: A method for testing capacity of at least one energy storage device of a pitch drive mechanism to drive a first rotor blade of a wind turbine connected to a power grid includes defining a rotor position range for implementing a first test procedure for the energy storage device(s). Further, the method includes monitoring a rotor position of the first rotor blade. When the rotor position of the first rotor blade enters the rotor position range, the method includes initiating the first test procedure. The first test procedure includes pitching the first rotor blade via the energy storage device(s), measuring at least one operating condition of the energy storage device(s) during pitching, and determining a capacity of the energy storage device(s) to drive the first rotor blade based on the operating condition(s) thereof.

Abstract: Methods of operating a variable speed wind turbine as a function of a wind speed, the wind turbine having a rotor with a plurality of blades, and one or more pitch mechanisms for rotating the blades. The method comprising a sub-nominal zone of operation for wind speeds below the nominal wind speed and a supra-nominal zone of operation for wind speeds above the nominal wind speed. In the supra-nominal zone, the blades are pitched so as to maintain the rotor speed substantially constant, and a tip speed ratio of the wind turbine is substantially continuously being determined and wherein an instantaneous minimum pitch angle is substantially continuously being determined based on the instantaneous tip speed ratio, and the blades are never pitched below the instantaneous minimum pitch angle. The disclosure further relates to a wind turbine suitable for carrying out such methods.

Abstract: A controller for controlling a system for changing the pitch of blades of a turbine engine propeller, the controller includes a fixed member (28) and a member (29) which is movable in translation along a longitudinal axis (X) relative to the fixed member (28), and an anti-rotation device (33) configured so as to prevent the rotation of the movable member (29) relative to the fixed member (28) about the axis (X). The anti-rotation device includes a longitudinal structural crossmember (35) which is mounted by a first and a second end (36, 37) on the fixed member, and support and guide unit (57) integrally in translation the movable member along the axis (X), the crossmember extending radially outside the movable member and the fixed member relative to a radial axis (Y) which is perpendicular to the axis (X) and being guided through the support and guide unit.

Abstract: A pitch drive system for a wind turbine includes a pitch drive motor, a first position detector, a driver, a second position detector, and a controller. When the blades rotate to a mechanical zero position, a position value detected by the first position detector is a first zero point position value. The driver is operable to store the first zero point position value. When the blades rotate to the mechanical zero position, a position value detected by the second position detector is a second zero point position value. The controller is operable to store the second zero point position value. When a corresponding back up command is received, the first zero point position value stored in the driver is backed up into the controller, and the second zero point position value stored in the controller is backed up into the driver respectively.

Abstract: A pitch control mechanism for an open rotor gas turbine engine is provided, the engine having a first rotor assembly and a second rotor assembly, with a plurality of airfoil blades circumferentially mounted on each rotor assembly, and arranged in contra-rotational relationship to each other. The pitch control mechanism includes an actuator assembly configured to be secured to a non-rotating frame of the engine, the actuator assembly having a first actuator and a second actuator, with the actuator assembly being rotationally isolatable from and couplable to the first and second rotor assemblies such that, in use, an actuation signal from the first or second actuator induces a corresponding desired change in pitch of the airfoil blades of the respective first or second rotor assembly independently of the pitch of the airfoil blades of the second or first rotor assembly.

Abstract: Embodiments of the present invention provide methods and apparatus for increasing turbulent mixing in the wake of at least one wind turbine. Doing so, increases efficiency of a wind turbine located in the wake by transferring energy to the wake that was lost when the wind passed through the upwind turbine. Turbulent mixing may be increased by changing the induction factor for a rotor by, for example, altering the pitch of the blades, the RPMs of the rotor, or the yaw of the nacelle. These techniques may be static or dynamically changing. Further, the different induction factors for a plurality of wind turbines may be synchronized according to a predetermined pattern to further increase turbulent mixing.

Abstract: The invention provides a heat-dissipating system and a control method thereof. The heat-dissipating system has a plurality of fans and is configured for adjusting rotation-speeds of the fans. The control method includes following steps: obtaining a plurality of rotation-speed values of the fans; computing out a rotation-speed reference value according to the rotation-speed values; when the rotation-speed reference value is greater than a first threshold value, decreasing the rotation-speeds of the fans through a corresponding fan control signal; when the rotation-speed reference value is less than a second threshold value, increasing the rotation-speeds of the fans through the corresponding fan control signal.

Abstract: A system and method for pressure based load measurement are provided. The system and method measure at least one pressure differential on an airfoil and determine at least one aerodynamic load associated with the at least one pressure differential. The determined at least one load is used to modify characteristics of the airfoil to increase efficiency and/or avoid damage. The determined at least one aerodynamic load may be further utilized to balance and/or optimize loads at the airfoil, estimate a load distribution along the airfoil used to derive other metrics about the airfoil, and/or used in a distributed control system to increase efficiency and/or reduce damage to, e.g., one or more wind turbines.

Abstract: A rotor system is provided wherein coaxial, closely spaced multi-bladed rotors counter-rotate at extremely low RPMs while their pitches are controlled to account for wind gusts and velocity conditions, thereby eliminating many of the deficiencies of conventional helicopters. The embodiments can dramatically decrease the power required to lift a given quantity of weight, even beyond the level required by a typical airplane.

Abstract: Described embodiments include a wind turbine system. In this embodiment, the system includes a wind turbine including a rotor blade having a controllable feature and attached to a rotor hub drivingly coupled to an electric generator. The controllable feature is configured if activated to decrease a noise generated by the rotor blade and correspondingly to decrease electric power generated by the electric generator. The wind turbine system includes a sensor configured to detect a parameter indicative of present or possible future noise generation state of the rotor blade. The wind turbine system includes a noise manager circuit configured to select a noise mitigation measure responsive to the detected parameter and in compliance with a minimum electric power generation requirement assigned to the wind turbine. The wind turbine system includes a control circuit configured to activate the controllable feature in response to the selected noise mitigation measure.

Abstract: A simple, robust and systematic control solution for open rotor control with a differential gearbox is disclosed. When the two counter rotating rotors of a CROR engine are conditioned by the differential gearbox, the two rotors speeds are coupled for given input torque. The solution provided by the current disclosure mathematically decouples these two rotors by transforming the original individual actuator input and speed output into differential & average input and output. Because the newly formed control system representation of the plant has decoupled input/output mapping, it follows that the simple SISO control can be applied. Furthermore, the current control solutions allow a simple and well-coordinated speed phase synchronizing among the four rotors on a two-engine vehicle.

Abstract: A marine vessel control apparatus is arranged to start and stop engines that are respectively provided in multiple propulsion devices. The marine vessel control apparatus includes multiple individual start/stop switches arranged to correspond to the respective multiple propulsion devices and arranged to be operated by an operator to individually start and stop the engines in the respective multiple propulsion devices, an all-device start/stop switch arranged to be operated by the operator to collectively start and stop the engines in the multiple propulsion devices, an operating state acquiring unit arranged to acquire operating states of the engines in the respective multiple propulsion devices, and a control unit. The control unit includes multiple input ports corresponding to the respective multiple individual start/stop switches. Each of the input ports is connected with the corresponding individual start/stop switch. All of the input ports are connected commonly with the all-device start/stop switch.

Abstract: A system and method are provided to increase efficiency of turbines in wind farms. A sensor is configured to generate a wind map of an inflow of wind. A controller is configured to generate a control signal based the wind map. A pitch adjustment device configured to adjust pitch of a blade of the turbine based on the control signal.

Abstract: A method of adjusting the speed of blades rotating in a rotor plane on a wind turbine, wherein the angle between at least two blades in the rotor plane is changed, whereby the tip speed of each individual blade can be optimised relative to the current speed of the wind experienced by the blade. Hereby it is possible to take into consideration the variation of the wind as a function of the height above ground level, and the yield of the wind turbine can be increased. The angular displacement of each blade can be changed individually independently of the remainder of the blades and cyclically. The method also comprises that each blade is accelerated on its way upwards in the rotation cycle and decelerated on its way down. Further details are provided about a system for controlling blades in a wind turbine comprising one or more wind speed meters, position meters, and/or acceleration meters, based on which parameters control of the angular displacement of each blade in the rotor plane is performed.

Abstract: A method an apparatus of automatically controlling a wind turbine re provided. of: A time-series of measurement values of the aerodynamic flow property of the wind turbine rotor blade is determined; a predictive wind field model representing a structure of a wind field acting on the wind turbine rotor blade is generated based on the time-series of measurement values, and a control value is generated based on the wind-field model.

Abstract: An interactive water fountain comprising means for providing at least one column or jet (1) of water, means for applying an electrical signal each column or jet (1), detector means (2) for detecting changes in electrical impedance of said water column or jet (1) caused by human interaction therewith and means for activating an electronic device capable of providing an auditory or visual effect upon detection of a change in electrical impedance.

Abstract: The present invention relates to an aerodynamic dead zone-less triple-rotor integrated wind power driven system wherein control rotor 81 disposed at up-wind is rotated at a high speed. It induced the air flowing into the hub of extenders 71 of the auxiliary rotor 71 to the outside of the extenders 71-1 of the auxiliary rotor 71, thereby forming an aerodynamic annular stream tube zone and increasing the air density therein, the main rotor 11 disposed at down-wind, is aerodynamically accelerating and improving the system efficiency. In addition, the rotor 52 and stator 51 of the electromagnetic attraction dragging rotational torque of the auxiliary generator by the load assists to rotate main rotor 11, thereby the triple rotors integrating rotational torque generates the twin generators 4 and 4-1? of the wind turbine.

Abstract: A method of operating a wind turbine generator having at least one wind turbine blade includes increasing a pitch angle of the at least one wind turbine blade as the at least one wind turbine blade rotates through a first range of blade azimuth values. Such increasing of the pitch angle reduces acoustic emissions generated by the wind turbine generator. The method also includes decreasing the pitch angle of the at least one wind turbine blade as the at least one wind turbine blade rotates through a second range of blade azimuth values. Such decreasing of the pitch angle increases electric power generated by the wind turbine generator.

Abstract: A method of operating a wind turbine above a predefined wind velocity comprising the step of operating a control parameter of the wind turbine within a tolerance band from a reference set-point curve of that control parameter. A wind turbine and a cluster of wind turbines is also contemplated.

Abstract: The present invention is vertical axis fluid flow turbine system for generating an alternative fuel. The turbines of the present invention are centered between at least two support structures so that the rotor holding the hub and the blades is perpendicular to the ground, rooftop, or the floor of a body of water and the axis of the blades coming from the hub are parallel to the ground, rooftop, floating structure, or the floor of a body of water. The turbines are secured to the support structures using struts. The struts are attached to each support structure and to the nacelle of each turbine. Attaching each turbine in this manner allows the turbines of the present invention to be stacked one on top of the other, that in turns minimizes the footprint of the vertical axis fluid flow turbine system.

Abstract: A dual, counter-rotating, coaxial rotor system provides individual control of an upper rotor system and a lower rotor system. The lower rotor control system and the upper rotor control system provide six controls or “knobs” to minimize or theoretically eliminate airframe vibration. In a dual, counter-rotating, coaxial rotor system, application of a HHC system to the two rotor systems individually but located on the common axis, will yield essentially complete vibration reduction because the 6 controls will suppress the 6 loads.

Abstract: A de-rotation system includes a first ring gear defined about an axis of rotation, a second ring gear defined about the axis of rotation and a gear set in meshing engagement with the first ring gear and the second ring gear to control a position of a housing about the axis of rotation.

Abstract: A rotor hub fairing system includes an upper hub fairing, a lower hub fairing and a shaft fairing therebetween. The rotor hub fairing system reduces the total drag on a dual, counter-rotating, coaxial rotor system. Other aerodynamic structures may be mounted to the shaft fairing, hub fairings and airframe to facilitate flow around the upper and lower hub fairings to reduce flow separation and drag.

Abstract: A rotor hub fairing system includes an upper hub fairing, a lower hub fairing and a shaft fairing therebetween. The rotor hub fairing system is sized and configured to reduce the overall drag on a dual, counter-rotating, coaxial rotor system. Preferably, the rotor hub fairing is fully integrated. The shaft fairing preferably includes a minimal thickness at the midsection to reduce drag with an increasing thickness adjacent the upper and lower hub fairings to reduce the flow separation on the hub fairing surfaces without overly excessive drag. Other aerodynamic structures, such as a horizontal splitter and/or a plurality of turning vanes may be mounted to the shaft fairing to facilitate flow around the upper and lower hub fairings to reduce flow separation and drag.

Abstract: A dual, counter rotating, coaxial rotor system provides an upper and lower rotor system, with a reduced axial rotor separation distance along a common axis by way of rotor tip position sensing and rotor position controls to avoid tip contact.

Abstract: A dual, counter rotating, coaxial rotor system provides an upper and lower rotor system, with a reduced axial rotor separation distance along a common axis by way of rotor tip position sensing and rotor position controls to avoid tip contact.

Abstract: A multi-bladed tail rotor assembly is disclosed that provides higher aerodynamic performance, damage tolerant design with 10,000-hour life expectancy, and which requires low maintenance through the use of composites and elastomerics. The tail rotor hub assembly includes two stacked yoke assemblies having multi-bladed teetering rotors, each mounted on a single drive mast. Each yoke assembly includes a yoke hub having a transverse bore therethrough, a bearing assembly disposed within the bore, and retention means for aligning and securing the bearing assembly within the bore. Each bearing assembly includes a trunnion portion having trunnion arms that extend outwardly from a trunnion body portion, and an elastomeric bearing disposed about each trunnion arm. The tail rotor assembly utilizes a composite twist strap flexure to accommodate collective pitch control integral with each rotor blade.

Abstract: A wind power installation is disclosed comprising a rotor having at least one rotor blade for converting the kinetic energy of the wind into mechanical energy, an adjusting device for individually adjusting at least one rotor blade, a generator for converting the mechanical energy of the rotor into electrical energy, and an operative connection between the rotor and the generator for transmitting the mechanical energy of the rotor to the generator. The disclosed wind power installation therefore avoids specified problems of known installations and provides a wind power installation in which the loadings which can occur due to local, temporary peaks in the wind speed in portions of the rotor area are reduced.

Abstract: In a helicopter having three or more rotor blades, and with mechanical actuation of the rotor blades by a swash plate and a superimposed electrohydraulic active control system, in addition to three regulating units (18) is an actuator (4) between a rotatable part (9) of the swash plate and a rotorblade mount (2) of each rotor blade. This arrangement allows for the safe actuation of individual blades in helicopter noise reduction, and increased efficiency at a modest constructional effort.

Abstract: An improved saddle stitching apparatus has dual scoring disks which cooperate with a scoring drum to create a flat spine on a cover. In one embodiment, a split ring is provided with two clamp arms, so that the ring can be releasably secured to the scoring drum. The ring includes a pair of annular grooves, with the distance between the grooves being of the desired spine width. The scoring disks are positioned adjacent the grooves so as to form the scoring lines. A folding assembly is also disclosed, which utilizes a flat carrying belt and a V-belt for purposes of folding the cover and moving the cover toward a stitching station. A gathering chain is also utilized to deliver the cover and signatures to the stitching station. The station includes a guide to assist in directing the preassembled covers and signatures toward a stitching head. Also provided is a block guide and an anvil for assistance in centering the spine beneath the stitching head.

Abstract: System for reducing vibrations in the cabin of an aircraft driven by two or more propellers each having n blades (n being an integer equal or larger than 2) of which the relative phase angle can be adjusted, said system comprising synchrophase means for adjusting said relative phase angle such that a predetermined relative phase angle is maintained. The system furthermore comprises means supplying information about the vibration level at one or more positions within the cabin or thereto related information and for generating a thereto corresponding level signal, and a control unit which in response to said level signal supplies an error signal to the synchrophase means causing the synchrophase means to adjust the blades of the various propellers such that a new relative phase angle is maintained which differs m.(2.pi./n) radians (m being an integer) from the previous relative phase angle.

Abstract: A propeller control system comprises a phase controller (11) having a phase control gain to control a propeller phase relationship, free air turbulence detection means (7, 9) and a gain controller (8) for varying the phase control gain in response to detected free air turbulence such that in the presence of turbulence a low gain is selected and in the absence of turbulence a high gain is selected. By varying the gain in this way the sensitivity of the phase controller (11) is reduced during turbulent conditions preventing excessive phase changes by the controller (11) striving to follow a turbulent master propeller. Similarly a speed controller (14) has its gain set by a gain controller (17) according to the degree of turbulence detected.

Abstract: System for reducing vibrations in the cabin of an aircraft driven by two or more propellers each having n blades (n being an integer equal or larger than 2) of which the relative phase angle can be adjusted, said system comprising synchrophase means for adjusting said relative phase angle such that a predetermined relative phase angle is maintained. The system furthermore comprises means supplying information about the vibration level at one or more positions within the cabin or thereto related information and for generating a thereto corresponding level signal, and a control unit which in response to said level signal supplies an error signal to the synchrophase means causing the synchrophase means to adjust the blades of the various propellers such that a new relative phase angle is maintained which differs m.(2.pi./n) radians (m being an integer) from the previous relative phase angle.

Abstract: System for reducing vibrations in the cabin of an aircraft driven by two or more propellers each having n blades (n being an integer equal or larger than 2) of which the relative phase angle can be adjusted, said system comprising synchrophase means for adjusting said relative phase angle such that a predetermined relative phase angle is maintained. The system furthermore comprises means supplying information about the vibration level at one or more positions within the cabin or thereto related information and for generating a thereto corresponding level signal, and a control unit which in response to said level signal supplies an error signal to the synchrophase means causing the synchrophase means to adjust the blades of the various propellers such that a new relative phase angle is maintained which differs m.(2.pi./n) radians (m being an integer) from the previous relative phase angle.

Abstract: A servo control system for a radio controlled co-axial rotor helicopter includes a receiver 4 to provide signals indicative of operator desired pitch, yaw, roll, and collective commands to an electronic mixer unit 30 which translates these command signals into six control signals 34-42 utilized by servos 50-60 to properly displace the rotor blades 256, 258.

Abstract: A tip brake is described for use on the blade of a wind generator so that the tip will be rotated relative to the remainder of the blade to slow the rotation of the rotor. The tip of the blade is rotatable, about its longitudinal axis, with respect to the remainder of the blade. A brake mechanism interconnects the blade tip with the remainder of the blade to cause the blade tip to be rotated when the blade is subjected to a predetermined amount of centrifugal force. Once the blade tip has been deployed to slow rotation of the rotor, it will remain deployed until the wind becomes very low or the rotor is manually slowed so that the spring can cause the tip to be reset.

Abstract: A counterrotatable bladed rotor assembly drivable by a rotatable shaft comprises a leading propeller, a trailing propeller, and a gearbox located axially between the two propellers and enclosed by a non-rotatable casing having an end for attachment to a support structure. The gearbox has a first output shaft to the leading propeller and a second output shaft to the trailing propeller. A first fluid-pressure operable actuator is provided to vary the pitch of the blades of the leading propeller, and a second fluid-pressure operable actuator is provided to vary the pitch of the blades of the trailing propeller. In addition passageways are provided to connect the first and second actuators to a source of fluid under pressure. The casing rotatably supports the second output shaft at a position between the gearbox and the leading propeller and rotatably supports the first output shaft at a position between the gearbox and the trailing propeller.

Abstract: An integrated control system for coaxial counterrotating aircraft propulsors driven by a common gas turbine engine. The system establishes an engine pressure ratio by control of fuel flow and uses the established pressure ratio to set propulsor speed. Propulsor speed is set by adjustment of blade pitch.

Abstract: An integrated control system for coaxial counterrotating aircraft propulsors driven by a common gas turbine engine. The system establishes an engine pressure ratio by control of fuel flow and uses the established pressure ratio to set propulsor speed. Propulsor speed is set by adjustment of blade pitch.

Abstract: A power management system is disclosed for an advanced helicoptor having h lift and thrust propulsion units and at least one power plant which comprises, a signal generator for generating a first signal which is proportional to the power available from the power plant, a power use gage connected to the lift propulsion unit which has an output that varies according to the amount of power used by that propulsion unit and a circuit which is connected to the power use gage and which receives the first signal for generating a second signal which is proportional to the amount of power remaining. The circuit is either used to power an indicator which indicates to the pilot the amount of power remaining for the thrust propulsion unit, or can be connected directly to a limit actuator for limiting the amount of power the pilot can apply to the thrust propulsion unit.

Abstract: A power management system is disclosed for an advanced helicopter having h lift and thrust propulsion units and at least one power plant which comprises, a signal generator for generating a first signal which is proportional to the power available from the power plant, a circuit connected to the lift propulsion unit which has an output that varies according to the amount of power used by that propulsion unit and which receives the first signal for generating a second signal which is proportional to the amount of power remaining. The circuit is either used to power a limit actuator for limiting the amount of power the pilot can apply to the thrust propulsion unit or drive an indicator which indicates to the pilot the amount of power remaining for the thrust propulsion unit, or perform both functions.

Abstract: A gas turbine engine control system is provided. In a preferred control system for use in combination with a helicopter, input signals respectively representative of power turbine speed error, power turbine shaft torque, and compressor shaft speed are employed. From these input signals, five intermediate signals are developed. One of the intermediate signals represents the main rotor speed error. Each of the five intermediate signals is provided with a separate predetermined gain and coupled to summation means. The predetermined gains are selected to be of values which reduce the effects of resonances provided by the main and tail rotors of the helicopter. The output of the summation means represents a control signal and may be employed to operate a fuel control valve.

Abstract: A control for a helicopter having dual, coaxial, counterrotating rigid rotors which varies the cyclic control phase angle of each rotor in flight as a function of vehicle forward speed to thereby control the coupling of lateral cyclic pitch with longitudinal cyclic pitch so as to introduce differential cyclic pitch inputs which automatically produce aerodynamic moments in each rotor to minimize maneuver generated gyroscopic precession moments, which also produce optimum lateral lift vector displacement for all flight speeds.