Wind turbine blade, wind power generation system including the same, and method for designing wind turbine blade

Patent metadata

Field	Value
Publication number	US-9790795-B2
Application number	US-201113825912-A
Country	US
Kind code	B2
Filing date	Oct 20, 2011
Priority date	Oct 22, 2010
Publication date	Oct 17, 2017
Grant date	Oct 17, 2017

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.

First claim

The invention claimed is:

1. A wind turbine blade comprising:
a blade body whose chord length increases from a blade tip toward a blade root,
the blade body including
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 first design lift coefficient over the entire blade tip region,
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 extending from the blade tip region to the maximum-chord-length position,
wherein the transition region has a design lift coefficient increasing gradually from the blade tip region to the maximum-chord-length position,
wherein the blade tip region is provided in a range of dimensionless radial positions of 0.5 to 0.95, the dimensionless radial position being a radial position of a blade section divided by a blade radius-that is a distance from the center of rotation of the blade to the blade tip, or is provided in a range of thickness ratios of 12% to 30%, the thickness ratio being a percentage obtained by dividing a maximum thickness by the chord length,
wherein the first design lift coefficient is X±0.10 or X±0.05, wherein X is a median of the first design lift coefficient,
wherein the second design lift coefficient of the maximum-chord-length position is X+0.3±0.2 or X+0.3±0.1, and
wherein the design lift coefficient of the transition region at a central position between an end of the blade tip region facing the blade root and the maximum-chord-length position is X+0.15±0.15 or X+0.15±0.075.

2. The wind turbine blade according to claim 1 , wherein
the first design lift coefficient is 1.15±0.05,
the second design lift coefficient of the maximum-chord-length position is 1.45±0.1, and
the design lift coefficient of the transition region at a central position between an end of
the blade tip region facing the blade root and the maximum-chord-length position is 1.30±0.075.

3. A wind power generation system comprising:
the wind turbine blade according to claim 1 ;
a rotor that is connected to the blade root of the wind turbine blade and that is rotated by the wind turbine blade; and
a generator that converts the rotational force generated by the rotor to electrical output power.

4. A wind turbine blade comprising:
a blade body whose chord length increases from a blade tip toward a blade root,
wherein the blade body is represented by a thickness ratio and Y125 which correlates with a design lift coefficient,
the thickness ratio being a percentage obtained by dividing a maximum thickness by the chord length,
Y125 being a percentage obtained by dividing a distance from a chord on a suction side, at a 1.25% position, by the chord length, wherein the position of a leading edge along the chord length is defined as 0% and the position of a trailing edge along the chord length is defined as 100%,
then the blade body has
a Y125 of 2.575±0.13% at a position having a thickness ratio of 21%,
a Y125 of 2.6±0.15% at a position having a thickness ratio of 24%, and
a Y125 of 2.75±0.25% or 2.75±0.20%, or 2.75±0.15%, at a position having a thickness ratio of 30%.

5. The wind turbine blade according to claim 4 , wherein Y125 of the blade body in a range of thickness ratios of 21% to 35% is determined by an interpolation curve passing through
the value of Y125 at the position having a thickness ratio of 21%,
the value of Y125 at the position having a thickness ratio of 24%, and
the value of Y125 at the position having a thickness ratio of 30%.

6. The wind turbine blade according to claim 4 , wherein the blade body has
a Y125 of 2.55±0.1% at a position having a thickness ratio of 18%,
a Y125 of 3.0±0.4% or 3.0±0.25% or 3.0±0.20%, at a position having a thickness ratio of 36%, and
a Y125 of 3.4±0.6% or 3.4±0.4% or 3.4±0.2%, at a position having a thickness ratio of 42%.

7. The wind turbine blade according to claim 6 , wherein Y125 of the blade body in a range of thickness ratios of 18% to 42% is determined by an interpolation curve passing through
the value of Y125 at the position having a thickness ratio of 18%,
the value of Y125 at the position having a thickness ratio of 21%,
the value of Y125 at the position having a thickness ratio of 24%,
the value of Y125 at the position having a thickness ratio of 30%,
the value of Y125 at the position having a thickness ratio of 36%, and
the value of Y125 at the position having a thickness ratio of 42%.

8. A wind power generation system comprising:
the wind turbine blade according to claim 4 ;
a rotor that is connected to the blade root of the wind turbine blade and that is rotated by the wind turbine blade; and
a generator that converts the rotational force generated by the rotor to electrical output power.

9. The wind turbine blade according to claim 4 , wherein Y125 is 2.75±0.20% at a position having a thickness ratio of 30%.

10. The wind turbine blade according to claim 4 , wherein Y125 is 2.75±0.15%, at a position having a thickness ratio of 30%.

11. A wind turbine blade comprising:
a blade body whose chord length increases from a blade tip toward a blade root,
wherein the blade body is represented by a thickness ratio and a suction-side convexity YS which correlates with a design lift coefficient,
the thickness ratio being a percentage obtained by dividing a maximum thickness by the chord length,
the suction-side convexity YS being a percentage obtained by dividing a distance from a chord on a suction side, at a maximum-thickness position, by the chord length,
then the blade body has
a suction-side convexity YS of 12.0±0.6% at a position having a thickness ratio of 21%,
a suction-side convexity YS of 12.3±0.7% at a position having a thickness ratio of 24%, and
a suction-side convexity YS of 13.3±1.2% or 13.3±1.0% or 13.3±0.8%, at a position having a thickness ratio of 30%.

12. The wind turbine blade according to claim 11 , wherein YS of the blade body in a range of thickness ratios of 21% to 35% is determined by an interpolation curve passing through
the value of YS at the position having a thickness ratio of 21%,
the value of YS at the position having a thickness ratio of 24%, and
the value of YS at the position having a thickness ratio of 30%.

13. The wind turbine blade according to claim 11 , wherein the blade body has
a YS of 11.7±0.5% at a position having a thickness ratio of 18%,
a YS of 14.6±2.0% or 14.6±1.2% or 14.6±1.0%, at a position having a thickness ratio of 36%, and
a YS of 16.6±3.0% or 16.6±2.0% or 16.6±1.5%, at a position having a thickness ratio of 42%.

14. The wind turbine blade according to claim 13 , wherein YS of the blade body in a range of thickness ratios of 18% to 42% is determined by an interpolation curve passing through
the value of YS at the position having a thickness ratio of 18%,
the value of YS at the position having a thickness ratio of 21%,
the value of YS at the position having a thickness ratio of 24%,
the value of YS at the position having a thickness ratio of 30%,
the value of YS at the position having a thickness ratio of 36%, and
the value of YS at the position having a thickness ratio of 42%.

15. A wind power generation system comprising:
the wind turbine blade according to claim 11 ;
a rotor that is connected to the blade root of the wind turbine blade and that is rotated by the wind turbine blade; and
a generator that converts the rotational force

Assignees

• Fukami Koji
• Mitsubishi Heavy Ind Ltd

Inventors

• Fukami Koji

Classifications

• F03D1/0641

  of the section profile of the blades, i.e. aerofoil profile · CPC title

• F05B2240/30

  Characteristics of rotor blades, i.e. of any element transforming dynamic fluid energy to or from rotational energy and being attached to a rotor · CPC title

• F03D1/0633 Primary

  of the blades · CPC title

• Y10T29/49336

  Blade making · CPC title

• F01D5/14 Primary

  Form or construction (selecting particular materials, measures against erosion or corrosion F01D5/28) · CPC title