Abstract: A manufacturing method of a wind turbine generator includes a cutting step of cutting a base blade at m cutting planes into (m+1) sections where m is an even number, the m cutting planes being at different positions in a blade length direction; and joining step of joining (m/2+1) sections of the (m+1) sections together to obtain a wind turbine blade which is shorter than the base blade, the (m/2+1) sections including a blade-root section which is closest to a blade root and a blade-tip section which is closest to a blade tip, the blade-root and blade-tip sections being non-adjacent to each other.

Abstract: Provided is a wind turbine blade that can improve aerodynamic performance in a blade-tip region and reduce aerodynamic noise. A wind turbine blade includes a blade body having a chord length that decreases from a blade root side to a blade tip side, wherein the blade body includes a blade-tip region in which a dimensionless radial position is within the range of 0.6 to 1.0, inclusive, the dimension less radial position being the ratio of radial position to blade radius (½ of a blade diameter), and a blade-body region in which the dimensionless radial position is smaller than 0.6, and wherein a maximum-blade-thickness position of a blade cross-section in the blade-tip region is closer to a leading edge than a maximum-blade-thickness position of a blade cross-section in the blade-body region.

Abstract: An operating method for a two-bladed wind turbine which comprises a rotor including two blades and a hub to which the two blades are coupled, the operating method includes a pitch-angle adjusting step of adjusting pitch angles of the two blades such that chords of the two blades are substantially parallel to a perpendicular direction to a rotational plane of the rotor during violent wind and a rotor holding step of holding the rotor at an azimuth angle such that the two blades are substantially parallel to a horizontal direction during the violent wind.

Abstract: When a distance from a front edge along a blade chord line is represented by X and a distance from the blade chord line to a blade back side is represented by Y, a blade back shape of a wind turbine blade includes a first region extending from the maximum blade thickness position toward the rear edge with dY/dX as a primary derivative amount of Y to X decreasing by a first amount of change, a second region on a side of the rear edge of the first region and extending toward the rear edge with dY/dX having a second amount of change smaller than the first amount of change, and a third region on the side of the rear edge of the second region and connected to the rear edge with dY/dX decreasing by a third amount of change larger than the second amount of change.

Abstract: A communication network of the present invention includes: a plurality of superordinate nodes 110 to 1m0 forming a cascade type topology; and a plurality of terminal nodes 111 to 11n, connected to at least one superordinate node from among said plurality of superordinate nodes and forming a star type topology with the superordinate node connected.

Abstract: A wind turbine blade includes a blade body whose chord length increases from a blade tip toward a blade root. The blade body includes a blade tip region located near the blade tip and whose chord length increases gradually toward the blade root, the blade tip region having a substantially constant first design lift coefficient, a maximum-chord-length position located near the blade root and having a maximum chord length, the maximum-chord-length position having a second design lift coefficient higher than the first design lift coefficient, and a transition region located between the blade tip region and the maximum-chord-length position. The transition region has a design lift coefficient increasing gradually from the first design lift coefficient to the second design lift coefficient in a direction from the blade tip toward the blade root.

Abstract: There is provided a yaw control technique for a wind turbine generator that can decrease the magnitude of the wind direction deviation even though the wind direction changes gradually over an extended period of time while suppressing an increase in the number of yaw rotations. Further, there is provided a yaw control technique for a wind turbine generator that can improve the efficiency of a wind turbine generator by performing yaw rotation at an appropriate timing through early detection of transitional changes in the wind direction.

Abstract: It is intended to provide a wind turbine blade with superior aerodynamic characteristics and rigidity, a wind turbine generator equipped with the wind turbine blade, and a method of designing the wind turbine blade. The wind turbine blade 1 is provided with a blade tip part 2, a blade root part 4 connected to a hub 112, and an airfoil part 6 disposed between the blade tip part 2 and the blade root part 4. The airfoil part 6 includes a flatback airfoil 10 with a blunt trailing edge 8 at least in an area in a longitudinal direction of the wind turbine blade 1 where a blade thickness ratio X is 40% to 50%. X indicates a ratio of a maximum thickness tMAX to a chord length LC. In the area where the blade thickness ratio X is 40% to 50%, the flatback airfoil has a trailing edge thickness ratio Y which is 5% to YH%, Y indicating a ratio of a trailing edge thickness tTE to the maximum thickness tMAX and YH has a relationship of YH=1.5X?30 with the blade thickness ratio X.

Abstract: It is intended to provide a wind turbine blade with superior aerodynamic characteristics and rigidity, a wind turbine generator equipped with the wind turbine blade, and a method of designing the wind turbine blade. The wind turbine blade 1 is provided with a blade tip part 2, a blade root part 4 connected to a hub 112, and an airfoil part 6 disposed between the blade tip part 2 and the blade root part 4. The airfoil part 6 includes a flatback airfoil 10 with a blunt trailing edge 8 at least in an area in a longitudinal direction of the wind turbine blade 1 where a blade thickness ratio X is 40% to 50%. X indicates a ratio of a maximum thickness tMAX to a chord length LC. In the area where the blade thickness ratio X is 40% to 50%, the flatback airfoil has a trailing edge thickness ratio Y which is 5% to YH%, Y indicating a ratio of a trailing edge thickness tTE to the maximum thickness tMAX and YH has a relationship of YH=1.5X?30 with the blade thickness ratio X.

Abstract: Provided is a wind turbine blade that can improve aerodynamic performance in a blade-tip region and reduce aerodynamic noise. A wind turbine blade includes a blade body having a chord length that decreases from a blade root side to a blade tip side, wherein the blade body includes a blade-tip region in which a dimensionless radial position is within the range of 0.6 to 1.0, inclusive, the dimension less radial position being the ratio of radial position to blade radius (½ of a blade diameter), and a blade-body region in which the dimensionless radial position is smaller than 0.6, and wherein a maximum-blade-thickness position of a blade cross-section in the blade-tip region is closer to a leading edge than a maximum-blade-thickness position of a blade cross-section in the blade-body region.

Abstract: Provided is a wind turbine blade realizing enhancement of performance by a winglet provided at a blade tip. The wind turbine blade includes the winglet formed by bending a tip side thereof toward a pressure side of the blade relative to an adjacent portion adjacent on a blade root side, and a CANT angle defined by a blade axial line of the winglet relative to a radial extrapolation line of a blade axial line of the adjacent portion is set to be 15° or more and 55° or less. The winglet includes a tip end located on a tip side thereof, having a substantially linear blade axial line, and a bent portion located on a base end side of the winglet and bent relative to the adjacent portion. This bent portion is bent gradually so as to satisfy the predetermined CANT angle.

Abstract: A centrifugal compressor in which frequency of noise produced by rotation of the impeller does not resonate with natural frequency of vibration of gas in a plurality of axial slots serving to increase gas flow rate in an operation range of increased gas flow rate and broaden stable operation range in an operation range of decreased gas flow rate is provided. The axial slots are formed between the peripheral part of the inlet passage of the compressor housing by the peripheral surface of the inlet passage and an annular ring part of the housing supported by a plurality of struts extending from the peripheral surface, four or more struts are provided to support the annular ring part, and all but one are located at positions determined when all the struts are located at circumferentially equal spacing and the one strut is shifted from the positions by a certain angle.

Abstract: A wind turbine generator system is provided with a nacelle supporting a wind turbine rotor, a nacelle rotation mechanism, an anemometer, and a control apparatus controlling the nacelle rotation mechanism. Said control apparatus calculates the wind direction deviation from the wind direction measured by the anemometer and the direction of the wind turbine rotor. Said control apparatus performs a yaw rotation of the nacelle by the nacelle rotation mechanism when any of conditions (1) and (2) is satisfied; the condition (1) is a condition under which a state where the absolute value of said wind direction deviation is equal to or more than a first threshold value continues for a first duration predetermined, and the condition (2) is a condition under which a state where the absolute value of said wind direction deviation is equal to or more than a second threshold value larger than said first threshold value continues for a second duration shorter than said first duration.

Abstract: There is provided a yaw control technique for a wind turbine generator that can decrease the magnitude of the wind direction deviation even though the wind direction changes gradually over an extended period of time while suppressing an increase in the number of yaw rotations. Further, there is provided a yaw control technique for a wind turbine generator that can improve the efficiency of a wind turbine generator by performing yaw rotation at an appropriate timing through early detection of transitional changes in the wind direction. The wind turbine generator includes a nacelle in which a wind turbine rotor is mounted, a rotating mechanism that performs yaw rotation of the nacelle, a wind direction measuring means that measures a wind direction, and a controller that controls the rotating mechanism.

Abstract: A communication network of the present invention includes: a plurality of superordinate nodes 110 to 1m0 forming a cascade type topology; and a plurality of terminal nodes 111 to 11n, connected to at least one superordinate node from among said plurality of superordinate nodes and forming a star type topology with the superordinate node connected.

Abstract: A wind turbine generator system is provided with a nacelle supporting a wind turbine rotor, a nacelle rotation mechanism, an anemometer, and a control apparatus controlling the nacelle rotation mechanism. Said control apparatus calculates the wind direction deviation from the wind direction measured by the anemometer and the direction of the wind turbine rotor. Said control apparatus performs a yaw rotation of the nacelle by the nacelle rotation mechanism when any of conditions (1) and (2) is satisfied; the condition (1) is a condition under which a state where the absolute value of said wind direction deviation is equal to or more than a first threshold value continues for a first duration predetermined, and the condition (2) is a condition under which a state where the absolute value of said wind direction deviation is equal to or more than a second threshold value larger than said first threshold value continues for a second duration shorter than said first duration.

Abstract: A centrifugal compressor can be provided with which frequency of noise produced by rotation of the impeller having a plurality of blades does not resonate with natural frequency of vibration of gas in a plurality of axial slots which serve to increase gas flow rate in an operation range of increased gas flow rate and broaden stable operation range in an operation range of decreased gas flow rate resulting in reduction of noise caused by rotation of the impeller.