Abstract: A flutter control system for a turbine includes a processor. The processor is configured to detect blade flutter of a turbine. The blade flutter indicates that blades of the turbine are in a deflected position different from a nominal operating position. The processor is configured to control operational parameters of the turbine that reduce or eliminate the blade flutter to improve the reliability and efficiency of the turbine.

Abstract: A calibration apparatus is configured to calibrate a magnetostrictive sensor. The magnetostrictive sensor is configured to measure an object and comprises a sensing element positioned adjacent to the object. The calibration apparatus comprises an estimation device and a calibrator. The estimation device is configured to estimate at least one of a gap between the sensing element and the object and a temperature of the object to obtain at least one of an estimated gap and an estimated temperature, based on geometric information, an excitation signal and an output signal of the magnetostrictive sensor, and geometric information of the object. The calibrator is configured to reduce an effect on the output signal of the magnetostrictive sensor imposed by variations in the at least one of the gap and the temperature, based on the at least one of the estimated gap and the estimated temperature, to obtain a calibrated output signal.

Abstract: A system for steering a drilling device comprising a drill pipe, is provided therein, the system comprising: a hoop sleeved on the drill pipe of the drilling device and having an outer diameter substantially equal to an inner diameter of a hole to be drilled; and a steering driving mechanism provided between the hoop and the drill pipe, for controlling a radial displacement of the drill pipe relative to a center axis of the hole to be drilled while drilling. The steering driving mechanism comprises one or more sub-mechanisms for connecting the hoop and the drill pipe and driving the drill pipe to move inside the hole, wherein each of the sub-mechanisms comprises an actuator adjustable in length, and a link element with one end rotatably coupled to the actuator and the other end rotatably coupled to hoop.

Abstract: A power generation system comprising a plurality of power generation units; a plurality of energy storage units; a plurality of switch units for connecting or disconnecting the power generation units and the energy storage units; and a controller for controlling the switch units to disconnect one or more idle power generation units from their corresponding energy storage units when the idle power generation units stop operating and to connect the disconnected energy storage unit to one operating power generation unit of the plurality of power generation units based on states-of-charge of the energy storage units. The power generation system may make best use of the energy storage units.

Abstract: A drilling system includes a drill string for connecting with a drill bit for drilling a borehole, a fixed stabilizer fixed on the drill string, and an active stabilizer including a body and actuators connecting the body and the drill string. The actuators are capable of driving the drill string away from a center of the borehole with a displacement. The body has an outer surface for contacting a wall of the borehole, an inner surface facing the drill string, and at least one guiding portion projecting from the inner surface and each defining at least one groove. The drill string includes at least one sliding portion slidable within the at least one groove respectively to constrain movement between the drill string and the active stabilizer along an axial direction of the drill string and guide movement between the drill string and the active stabilizer perpendicular to the axial direction.

Abstract: A rotary steerable drilling system includes a collar, a drill bit, and a bit shaft connecting the drill bit to the collar. The bit shaft is coupled to the collar through a joint capable of transmitting a torque from the collar to the bit shaft and is swingable with respect to the collar around the joint. The system, further includes first eccentric wheel and second eccentric wheel coupled to the bit shaft and rotatable to swing the bit shaft with respect to the collar around the joint to change a drilling direction, a controller for controlling the first eccentric wheel and second eccentric wheel to harmoniously rotate such that the swing of the bit shaft substantially compensates rotation of the bit shaft, and an active stabilizer mounted on the bit shaft and capable of pushing the bit shaft to deviate to cause a lateral displacement and a tilt angle of the drill bit.

Abstract: A drilling system includes a rotatable string for connecting with a bit for drilling a borehole, and an active stabilizer which includes a body having an outer surface for contacting a wall of the borehole, and a plurality of actuators connecting the body and the string and capable of driving the string to deviate away from a center of the borehole with a displacement to change a drilling direction. The drilling system further includes a module for measuring direction parameters including at least one of a declination angle and an azimuth angle of the borehole, a module for measuring imbalance parameters including at least one of a lateral force, a bending moment and a torque near the drill dit, and a controller including a calculator for calculating an adjustment needed for the displacement, based on the measured parameters and expected values of these parameters.

Abstract: An auto-adjustable directional drilling apparatus comprises: a drive-shaft housing; a drill collar coupled to the drive-shaft housing; a drive shaft passing through the drive-shaft housing and the drill collar; an active stabilizer fixed to the drive-shaft housing and movably coupled to the drill collar; a sliding assembly comprising a base support fixed to the drill collar and a sliding base coupled to the drive-shaft housing, wherein the base support defines a slide way and the sliding base is slidably disposed in the slide way; and an actuating module coupled to the sliding base to drive the sliding base to slide along the slide way. An auto-adjustable directional drilling method is also disclosed.

Abstract: The present subject matter is directed to a wind turbine blade alignment method. A sensor provided on the blade at a blade station with a known twist angle is used to measure an installation angle of the blade station. The installation angle is adjusted if the installation angle measured by the sensor is not equal to the known twist angle. A wind turbine with such a sensor for measuring an installation angle used for blade alignment is also provided.

Abstract: A flutter control system for a turbine includes a processor. The processor is configured to detect blade flutter of a turbine. The blade flutter indicates that blades of the turbine are in a deflected position different from a nominal operating position. The processor is configured to control operational parameters of the turbine that reduce or eliminate the blade flutter to improve the reliability and efficiency of the turbine.

Abstract: A wind turbine including a plurality of blades, a micro inertial measurement unit installed on each blade and configured to sense a plurality of detection parameter signals at corresponding installation positions, and a monitoring system configured to monitor an operating state of the blades. The monitoring system includes a signal processing unit configured to obtain a processing parameter signal through calculation based on the detection parameter signals, a signal analyzing unit configured to analyze each analysis parameter signal, selected from the plurality of detection parameter signals and the processing parameter signal, to obtain a fault estimation signal, used to estimate whether a corresponding blade works in a fault state, and a fault evaluating unit configured to evaluate, based on a plurality of fault estimation signals, whether a corresponding blade fails or a probability that the corresponding blade fails.

Abstract: A power generation system is provided. The system includes a bus, at least two converters, an energy-type energy storage unit (ES), a power-type energy storage unit (PS) and a controller. The ES and the PS are coupled in parallel to the bus through corresponding converters of the at least two converters. The controller is configured to control the ES and the PS through the corresponding converters in at least two conditions during a charging mode and a discharging mode: when a power for the ES and PS is below a power threshold, control the power to flow between the ES and the bus; and when the power is above the power threshold, control a part of the power to flow between the ES and the bus and another part of the power to flow between the PS and the bus. And a method for generating power is also provided.

Abstract: A wind turbine includes a rotor comprising multiple blades mounted on a hub, MIMUs mounted on each blade for sensing parameter signals thereof, and a control system. The control system includes a wind speed calculation unit, a wind shear calculation unit, a pitch angle compensation command calculation unit, and a pitch control unit. The wind speed calculation unit is used for calculating wind speeds at the blades based at least on the sensed parameter signals. The wind shear calculation unit is used for calculating a characteristic shear exponent based at least on the calculated wind speeds. The pitch angle compensation command calculation unit is used for calculating pitch angle compensation commands of the blades based at least on the calculated characteristic shear exponent. The pitch control unit is used for adjusting the pitch angles of the blades based on the calculated pitch angle compensation commands.

Abstract: A calibration apparatus is configured to calibrate a magnetostrictive sensor. The magnetostrictive sensor is configured to measure an object and comprises a sensing element positioned adjacent to the object. The calibration apparatus comprises an estimation device and a calibrator. The estimation device is configured to estimate at least one of a gap between the sensing element and the object and a temperature of the object to obtain at least one of an estimated gap and an estimated temperature, based on geometric information, an excitation signal and an output signal of the magnetostrictive sensor, and geometric information of the object. The calibrator is configured to reduce an effect on the output signal of the magnetostrictive sensor imposed by variations in the at least one of the gap and the temperature, based on the at least one of the estimated gap and the estimated temperature, to obtain a calibrated output signal.

Abstract: A measurement-while-drilling device comprises a base (21) to be connected between the drill pipe and the drill bit, the base having first and second end surfaces (212, 213) at the two axial ends thereof, at least one sensing chamber (22) which has an opening at at least one of the end surfaces, and a passage (23) for circulation of drilling fluid, at least one sensor disposed within the sensing chamber, and a sealing member (26) for sealing the sensing chamber on the at least one end surface.

Abstract: A system for steering a drilling device comprising a drill pipe, is provided therein, the system comprising: a hoop sleeved on the drill pipe of the drilling device and having an outer diameter substantially equal to an inner diameter of a hole to be drilled; and a steering driving mechanism provided between the hoop and the drill pipe, for controlling a radial displacement of the drill pipe relative to a center axis of the hole to be drilled while drilling. The steering driving mechanism comprises one or more sub-mechanisms for connecting the hoop and the drill pipe and driving the drill pipe to move inside the hole, wherein each of the sub-mechanisms comprises an actuator adjustable in length, and a link element with one end rotatably coupled to the actuator and the other end rotatably coupled to hoop.

Abstract: A wind turbine includes multiple blades, multiple Micro Inertial Measurement Units (MIMUs) for sensing parameter signals of the blades, and a control system. The control system includes a blade bending moment calculation unit, a blade bending moment error signal calculation unit, and a pitch angle compensation command calculation unit. The blade bending moment calculation unit is used for calculating blade bending moment values of the blades based at least on the sensed parameters. The blade bending moment error signal calculation unit is used for calculating blade bending moment error signals of the blades based on the calculated blade bending moment values of the blades and multiple blade bending moment commands. The pitch angle compensation command calculation unit is used for calculating pitch angle compensation commands of the blades based on the calculated blade bending moment error signals to adjust pitch angles of the blades respectively.

Abstract: A power generation system comprising a plurality of power generation units; a plurality of energy storage units; a plurality of switch units for connecting or disconnecting the power generation units and the energy storage units; and a controller for controlling the switch units to disconnect one or more idle power generation units from their corresponding energy storage units when the idle power generation units stop operating and to connect the disconnected energy storage unit to one operating power generation unit of the plurality of power generation units based on states-of-charge of the energy storage units. The power generation system may make best use of the energy storage units.

Abstract: A power generation system is provided. The system includes a bus, at least two converters, an energy-type energy storage unit (ES), a power-type energy storage unit (PS) and a controller. The ES and the PS are coupled in parallel to the bus through corresponding converters of the at least two converters. The controller is configured to control the ES and the PS through the corresponding converters in at least two conditions during a charging mode and a discharging mode: when a power for the ES and PS is below a power threshold, control the power to flow between the ES and the bus; and when the power is above the power threshold, control a part of the power to flow between the ES and the bus and another part of the power to flow between the PS and the bus. And a method for generating power is also provided.

Abstract: A system for determining a real time solid flow rate of a solid-gas mixture is provided. The system includes multiple sensors, a data-fusion unit and an estimating unit. The sensors generate multiple measurement signals for obtaining at least two measured values of the real time solid flow rate. The data-fusion unit receives the measured values and establishes a state-space model based on the measured values. The estimating unit estimates the state-space model to generate an estimated value of the real time solid flow rate. A method for determining a real time solid flow rate of a solid-gas mixture is also presented.