The blade design method of the wind driven generator is modified on the basis of Schmits and Glauert calculation models. The Schmits and Glauert calculation model refers to chord length and installation angle parameters of the blade. The chord length and the mounting angle are the chord length and the mounting angle of the airfoil of the blade at the radius r. The correction theory and the calculation formula refer to correction coefficient K which is obtained by derivation, analysis and experiment and is supplemented with a Schmits and Glauert calculation model_cs、K_θsThe chord length and the mounting angle of the obtained blade.

C_rs＝K_cs*C_r；

θ_rs＝K_θs*θ_r；

Said C is_rsTo correct the chord length, K_csAs a chord length correction factor, C_rCalculating model chord length, θ, for Schmits or Glauert_rsTo correct the mounting angle, K_θsFor correcting mounting angleNumber, theta_rCalculating the model chord length for Schmits or Glauert; establishing a correction coefficient K of chord length related to the starting wind speed, the rated wind speed, the tip speed ratio, the number of blades and the distance between the cross section and the center of the blade of the wind driven generator_crsWhen K is_crsWhen the chord length is more than or equal to 1, correcting the chord length C_rsIs equal to the correction factor K_crsAnd Schmits or Glauert calculation model chord length C_rThe product of (a); when the correction coefficient K is_crsWhen the chord length is less than 1, correcting the chord length C_rsEqual to Schmits or Glauert calculation model chord length C_r. Wherein K_crsThe mathematical model of (a) is:

the V is_sThe starting wind speed value is preset for the wind driven generator, and the range of the Vs value is 1.2-3.2 m/s;

the V is_aFor rated wind speed value of the wind power generator, said V_aThe value range is 8-12 m/s;

the lambda is the tip speed ratio of the wind driven generator blade and satisfies the relation:

for a high-speed fan, the value range is usually between 5 and 8.

B is the number of blades of the wind driven generator, and the value is 2-6;

r is the distance from the blade section of the wind driven generator to the center of the wind wheel;

and R is the design radius of the wind driven generator blade.

Setting a correction coefficient K of a mounting angle related to the starting wind speed, the rated wind speed, the tip speed ratio, the number of blades and the distance between the cross section and the center of the blade of the wind driven generator_θrsWhen K is_θsWhen the angle is greater than or equal to 1, correcting the installation angle theta_rsIs equal to the correction factor K_θrsCalculating a model installation angle theta with Schmits or Glauert_rThe product of (a); when the correction coefficient K is_θrsWhen the angle is less than 1, the mounting angle theta is corrected_rsEqual to the Schmits or Glauert calculation model mounting angle theta_r. Wherein K_θrsThe mathematical expression of (a) is:

the above-mentioned

for high speed windThe value range of the machine is usually between 5 and 8.

B is the number of blades of the wind driven generator, and the value is 2-6;

and R is the design radius of the wind driven generator blade.

In the present embodiment, the correction coefficient K of the chord length_crsAnd correction factor K of mounting angle_θrsUnder the common influence of the starting wind speed of the fan, the rated wind speed, the tip speed ratio, the number of the blades and the distance between the cross section and the center of the blade, the correction coefficient can make a suitable change trend after any variable is adjusted. Correction coefficient K of chord length_crsAnd correction factor K of mounting angle_θrsThe correction effect of (2) is mainly concentrated on the area of the blade close to the root part, and the correction is smaller when the blade is closer to the blade tip part until the correction coefficient is 1. Starting wind speed V_sRated wind speed V as the main variable_aTip speed ratio λ, blade number B as auxiliary variables. The calculated length of the blade is increased by 3-15% compared with a standard theoretical calculation method according to the required starting wind speed. The lower the start-up wind speed requirement, the larger the value of the increase.

The invention relates to a corrected chord length C calculated after the blade of a wind driven generator is corrected_rsAnd correcting the mounting angle theta_rsThe correction is within 10% of the design correction theory and the calculation result of the calculation model in the reasonable extension range of the calculation model, and the basic ideas and ideas of the blade design correction theory and the calculation model are still used.

In this embodiment, a winglet smoothly connected to the tip of the blade is provided. The winglet is of a symmetrical wing type structure, the length of the winglet is 5% -10% of the designed length of the blade, the winglet inclines backwards from the windward side, the inclination angle is 15-60 degrees, the winglet inclines backwards along the rotation plane of the impeller along the downwind direction, the inclination angle is 8-30 degrees, the connection radius of the winglet and the blade tip is 1/4 of the length of the winglet, and the number of the wing types used in the length of all the blades is 1-3.

The above description is only an embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications of equivalent structures and equivalent processes, which are made by the present specification, or directly or indirectly applied to other related technical fields, are included in the scope of the present invention.

Claims

1. A blade of a wind driven generator is characterized in that the blade comprises a root part used for installation at one end and a blade tip at the other end, the installation angle of the blade adjacent to the root part is larger than that of the blade tip, the chord length of the blade increases in a nonlinear acceleration mode in the area adjacent to the root part, and the chord length and the installation angle of the blade are obtained through modification through a Schmits or Glauert calculation model;

C_rs=K_cs*C_r；

θ_rs=K_θs*θ_r；

wherein,

K_cs=K_crswhen K is_crsWhen greater than 1;

K_cs= 1-when K_crsLess than 1;

K_θs=K_θrswhen K is_θrsWhen greater than 1;

K_θs= 1-when K_θrsLess than 1;

the above-mentioned

The above-mentioned

The V is_sScheduled start-up for wind generatorsDynamic wind speed value, said V_aThe wind power generation method comprises the following steps that a rated wind speed value of the wind driven generator is obtained, lambda is the tip speed ratio of a wind driven generator blade, B is the number of the wind driven generator blade, R is the distance between the section of the wind driven generator blade and the center of a wind wheel, and R is the design radius of the wind driven generator blade;

the range of the Vs value is 1.2-3.2 m/s, and the V value is_aThe value range is 8-12 m/s, the value range of lambda is 5-8, and the value range of B is 2-6.

2. Blade for a wind turbine according to claim 1, wherein the length of the blade is increased by 3% compared to a standard theoretical calculation method^-15% and is inversely proportional to the starting wind speed.

3. The blade of the wind power generator as claimed in claim 2, wherein the tip of the blade is provided with a winglet smoothly connected.

4. The blade of claim 3, wherein the winglet is a symmetrical airfoil configuration having a length of 5% of a blade design length^-10% of winglets inclined backwards from the windward side, and the inclination angle is 15 degrees^-60 degrees, the winglet is inclined backwards downwind along the plane of rotation of the impeller, the angle of inclination being 8 degrees^-30 degrees and the radius of the winglet to the tip is 1/4 the length of the winglet.

5. A wind power generator comprising a blade, wherein the blade comprises a root part used for installation at one end and a blade tip at the other end, the installation angle of the blade adjacent to the root part is larger than that of the blade tip, the chord length of the blade increases in the area adjacent to the root part in a nonlinear acceleration mode, and the chord length and the installation angle of the blade are obtained through modification through a Schmits or Glauert calculation model;

C_rs=K_cs*C_r；

θ_rs=K_θs*θ_r；

wherein,

K_cs=K_crswhen K is_crsWhen greater than 1;

K_cs= 1-when K_crsLess than 1;

K_θs=K_θrswhen K is_θrsWhen greater than 1;

K_θs= 1-when K_θrsLess than 1;

the above-mentioned

The above-mentioned

The V is_sA predetermined starting wind speed value for the wind turbine, said V_aThe wind power generation method comprises the following steps that a rated wind speed value of the wind driven generator is obtained, lambda is the tip speed ratio of a wind driven generator blade, B is the number of the wind driven generator blade, R is the distance between the section of the wind driven generator blade and the center of a wind wheel, and R is the design radius of the wind driven generator blade;