CN104675621A - Method and system for determining blade control parameter of variable speed and variable pitch wind generating set - Google Patents

Abstract

The invention provides a method and a system for determining a blade control parameter of a variable speed and variable pitch wind generating set. The method comprises the following steps: monitoring current set power of a target variable speed and variable pitch wind generating set in real time; determining a curve between a wind power utilization coefficient and a tip speed ratio of the target variable speed and variable pitch wind generating set; determining an intersection point between the wind power utilization coefficient and the tip speed ratio corresponding to different pitch angles and a set power value at current air density corresponding to the intersection point; when the monitored current set power meets a set power set value, determining a minimum pitch angle corresponding to the current set power under the condition of avoiding blade stall; when the current set power is within the range of two set power set values, determining the minimum pitch angle corresponding to the current set power under the condition of avoiding blade stall by using an interpolation method. The purposes of avoiding the blade stall and improving the set operation stability and the power generation under the condition that the original design of the set is not changed can be achieved.

Description

Determine the method and system of speed-changing oar-changing wind power generation unit blade controling parameters

Technical field

The application relates to wind turbine control system field, particularly a kind of method and system determining speed-changing oar-changing wind power generation unit blade controling parameters.

Background technique

Along with the development of technology, people are more and more higher to the requirement avoiding speed-changing oar-changing wind power generation unit blade to lose efficacy.

The existing method of blade stall of avoiding is by improving unit rated speed, selects the high blade of the leaf power of the assembling unit and select the methods such as more large sized unit blade (namely selecting more linear leaf) to solve the problem of blade stall near Wind turbines rated wind speed.Although these methods to some extent solve the problem of blade stall near the Wind turbines rated wind speed of high altitude localities, but these methods are also not suitable for the problem solving the blade stall that the factor outside high altitude localities causes, and these methods can bring the increase of load of wind turbine generator level even to affect the change of part design type selecting, its Wind turbines for the generation stall event run avoids stall to there is no improvement.

Therefore, how avoid blade stall not changing in the intrinsic situation of unit, improve unit operation stable type and generated energy is the current technical issues that need to address of those skilled in the art.

Summary of the invention

Technical problems to be solved in this application are to provide a kind of method and system determining speed-changing oar-changing wind power generation unit blade controling parameters, to solve in prior art and to be not suitable for solving the problem of the blade stall that the factor outside high altitude localities causes, and these methods can bring the increase of load of wind turbine generator level even to affect the change of part design type selecting, its Wind turbines for the generation stall event run avoids stall to there is no the problem of improvement.

Its concrete scheme is as follows:

This application provides a kind of method determining speed-changing oar-changing wind power generation unit blade controling parameters, the method comprises:

Real-Time Monitoring target shift speed becomes the current power of the assembling unit of oar Wind turbines;

In different propeller pitch angle situation, determine that target shift speed becomes the curve between the power coefficient of oar Wind turbines and tip-speed ratio; Determine the intersection point between the power coefficient that different propeller pitch angle is corresponding and tip-speed ratio curve, and the power of the assembling unit value under present air density corresponding to intersection point;

$p=\frac{1}{2}{\mathrm{\ρC}}_p(\mathrm{\β},\mathrm{\λ})\frac{{\mathrm{\ω}}^3{R}^5}{{\mathrm{\λ}}^3}\mathrm{\π}$

In formula, P is the power of the assembling unit, and ρ is air density, C _pfor power coefficient, β is propeller pitch angle, λ tip speed ratio, and ω is wind speed round, and R is wind wheel radius;

When the current power of the assembling unit of described monitoring meets power of the assembling unit setting value, then according to presetting method, the minimum propeller pitch angle that under determining to avoid described blade stall situation, the described current power of the assembling unit is corresponding;

When the described current power of the assembling unit is in two described power of the assembling unit ranges of set value, utilize the method for interpolation, the minimum propeller pitch angle that under determining to avoid described blade stall situation, the described current power of the assembling unit is corresponding.

Above-mentioned method, preferably, described according to presetting method, the minimum propeller pitch angle that under determining to avoid described blade stall situation, the described current power of the assembling unit is corresponding is:

The current power of the assembling unit p=pa of oar Wind turbines is become in described target shift speed _nor p=pb _ntime, avoid the minimum propeller pitch angle of blade stall to be n degree;

Wherein, pa _nand pb _npower of the assembling unit value under present air density corresponding to the intersection point between power coefficient corresponding under n-1 degree and n degree propeller pitch angle situation and tip-speed ratio curve, n with n-1 is the different propeller pitch angle of described blade.

Above-mentioned method, preferably, utilizes the method for interpolation, and the minimum propeller pitch angle that under determining to avoid described blade stall situation, the described current power of the assembling unit is corresponding comprises:

The current power of the assembling unit becoming oar Wind turbines in described target shift speed is in pa _n≤ p≤pa _n+1and pb _n>=p>=pb _n+1between time, adopt following interpolation method to determine the minimum propeller pitch angle θ avoiding blade stall:

$\begin{array}{cc}\mathrm{\θ}=n+\frac{p-{\mathrm{pa}}_n}{{\mathrm{pa}}_{n+1}-{\mathrm{pa}}_n}& {\mathrm{pa}}_n\≤p\≤{\mathrm{pa}}_{n+1}\end{array}$

$\begin{array}{cc}\mathrm{\θ}=n+\frac{p-{\mathrm{pa}}_{n+1}}{{\mathrm{pa}}_n-{\mathrm{pa}}_{n+1}}& {\mathrm{pa}}_n\≥p\≥{\mathrm{pa}}_{n+1}\end{array}$

Wherein, pa _nand pb _npower of the assembling unit value under present air density corresponding to the intersection point between power coefficient corresponding under n-1 degree and n degree propeller pitch angle situation and tip-speed ratio curve, pa _n+1and pb _n+1power of the assembling unit value under present air density corresponding to the intersection point between power coefficient corresponding under n+1 degree and n degree propeller pitch angle situation and tip-speed ratio curve, n, n-1 and n+1 are the different propeller pitch angle of described blade.

Present invention also provides a kind of system determining speed-changing oar-changing wind power generation unit blade controling parameters, this system comprises:

Monitoring cell, becomes the current power of the assembling unit of oar Wind turbines for Real-Time Monitoring target shift speed;

First determining unit, in different propeller pitch angle situation, determines that target shift speed becomes the curve between the power coefficient of oar Wind turbines and tip-speed ratio;

Second determining unit, for determining the intersection point between the power coefficient that different propeller pitch angle is corresponding and tip-speed ratio curve, and the power of the assembling unit value under present air density corresponding to intersection point;

3rd determining unit, for when the current power of the assembling unit of described monitoring meets power of the assembling unit setting value, then according to presetting method, the minimum propeller pitch angle that under determining to avoid described blade stall situation, the described current power of the assembling unit is corresponding;

4th determining unit, for when the described current power of the assembling unit is in two described power of the assembling unit ranges of set value, utilizes the method for interpolation, the minimum propeller pitch angle that under determining to avoid described blade stall situation, the described current power of the assembling unit is corresponding.

This application provides a kind of method determining speed-changing oar-changing wind power generation unit blade controling parameters, Real-Time Monitoring target shift speed becomes the current power of the assembling unit of oar Wind turbines; In different propeller pitch angle situation, determine that target shift speed becomes the curve between the power coefficient of oar Wind turbines and tip-speed ratio; Determine the intersection point between the power coefficient that different propeller pitch angle is corresponding and tip-speed ratio curve, and the power of the assembling unit value under present air density corresponding to intersection point; When the current power of the assembling unit of described monitoring meets power of the assembling unit setting value, then according to presetting method, the minimum propeller pitch angle that under determining to avoid described blade stall situation, the described current power of the assembling unit is corresponding; When the described current power of the assembling unit is in two described power of the assembling unit ranges of set value, utilize the method for interpolation, the minimum propeller pitch angle that under determining to avoid described blade stall situation, the described current power of the assembling unit is corresponding.Can be issued to and avoid blade stall not changing the intrinsic situation of unit, improve the object of unit operation stable type and generated energy.

Accompanying drawing explanation

In order to be illustrated more clearly in the technological scheme in the embodiment of the present application, below the accompanying drawing used required in describing embodiment is briefly described, apparently, accompanying drawing in the following describes is only some embodiments of the application, for those of ordinary skill in the art, under the prerequisite not paying creative work, other accompanying drawing can also be obtained according to these accompanying drawings.

Fig. 1 is a kind of flow chart determining the embodiment of the method for speed-changing oar-changing wind power generation unit blade controling parameters of the application;

Fig. 2 is the application's Leaf aerofoil profile angle of attack schematic diagram;

Fig. 3 is the function curve in the application between the power coefficient of certain MW level speed-changing oar-changing Wind turbines in different propeller pitch angle situation and the power of the assembling unit;

Fig. 4 is a kind of structural representation determining the system embodiment of speed-changing oar-changing wind power generation unit blade controling parameters of the application;

Fig. 5 is a kind of method practical application determining speed-changing oar-changing wind power generation unit blade controling parameters of the application;

Fig. 6 is a kind of another practical application of method determining speed-changing oar-changing wind power generation unit blade controling parameters of the application.

Embodiment

Below in conjunction with the accompanying drawing in the embodiment of the present application, be clearly and completely described the technological scheme in the embodiment of the present application, obviously, described embodiment is only some embodiments of the present application, instead of whole embodiments.Based on the embodiment in the application, those of ordinary skill in the art are not making the every other embodiment obtained under creative work prerequisite, all belong to the scope of the application's protection.

With reference to figure 1, show a kind of flow chart determining the embodiment of the method for speed-changing oar-changing wind power generation unit blade controling parameters of the application, can comprise the following steps:

Step S101: Real-Time Monitoring target shift speed becomes the current power of the assembling unit of oar wind power generation unit blade.

With reference to figure 2, show vane airfoil profile angle of attack schematic diagram, wherein, W is relative speed of wind, and α is the angle of attack, and β is propeller pitch angle, and Φ is inflow angle, and Ω is rotating speed, U _∞for incoming flow wind speed, r is aerofoil profile place wind wheel radial location, a and a ' is pneumatic inducible factor, as can see from Figure 2, the angle of attack of aerofoil profile is relevant to wind speed, rotating speed and propeller pitch angle, in unit wind speed and rotating speed one timing, can reduce the angle of attack of vane airfoil profile by increasing blade pitch angle, when the angle of attack of aerofoil profile is decreased to after within stall angle scope, blade will avoid stall.

Because the angle of attack of blade each cross section aerofoil profile cannot directly be measured, need by indirectly reflecting that the unit operation parameter of the vane airfoil profile operation angle of attack reflects, because the angle of attack of vane airfoil profile is relevant to wind speed, rotating speed and tip speed ratio, angle of attack size can be reflected by the unit power coefficient that the lift of blade is relevant, therefore, can judge whether blade is in stall conditions theoretically by investigating the Wind turbines power coefficient in different established angle situation-tip-speed ratio tip speed ratio curve.

The speed (peripheral velocity) of tip speed ratio tip-speed ratio and blade tip is divided by the speed in great distances before wind contact blade, and blade is longer, or blade rotational speed is faster, also larger with the tip speed ratio tip-speed ratio under wind speed.

The pitch control method of blade stall of avoiding based on tip-speed ratio will be subject to the impact of measuring wind speed accuracy in actual applications, for adopting as the Wind turbines that wind etc. accurately surveys wind devices surveyed by lidar, can the tip-speed ratio of Real-Time Monitoring Wind turbines, and for current most of speed-changing oar-changing Wind turbines, wind finding device is normally arranged on the anemoclinograph of cabin afterbody, owing to being subject to the impact of wind wheel, it surveys the incoming flow wind speed that wind data can not prepare to reflect wind wheel reality, therefore tip-speed ratio can not Obtaining Accurate in real time, now can realize according to the power monitoring of Wind turbines the pitch control method avoiding blade stall.

Owing to meeting following relation between tip-speed ratio and the power of the assembling unit:

$p=\frac{1}{2}{\mathrm{\ρC}}_p(\mathrm{\β},\mathrm{\λ})\frac{{\mathrm{\ω}}^3{R}^5}{{\mathrm{\λ}}^3}\mathrm{\π}$

In formula, ρ is air density, C _pfor power coefficient, β is propeller pitch angle, λ tip speed ratio, and ω is wind speed round, and R is wind wheel radius.

From above formula, when real-time monitoring the current power of the assembling unit, current tip-speed ratio can be obtained by the relation between the power of the assembling unit and tip-speed ratio, and power of the assembling unit monitoring rate is more accurate, therefore, the power of the assembling unit is adopted to replace tip-speed ratio to carry out determining speed-changing oar-changing wind power generation unit blade controling parameters in the application.

In the application, the current power of the assembling unit value of Real-Time Monitoring, to determine the power of the assembling unit in each moment, ensures the real-time of the data obtained, authenticity and reliability.

Step S102: in different propeller pitch angle situation, determines that target shift speed becomes the curve between the power coefficient of oar Wind turbines and tip-speed ratio.

Step S103: determine the intersection point between the power coefficient that different propeller pitch angle is corresponding and tip-speed ratio curve, and the power of the assembling unit value under present air density corresponding to intersection point.

With reference to figure 3, indicate the function curve between the power coefficient of certain MW level speed-changing oar-changing Wind turbines in different propeller pitch angle situation and tip-speed ratio, known, what different propeller pitch angles herein adopted is 0 degree, 1 degree, 2 degree and 3 degree, depict the power coefficient Cp-tip-speed ratio λ curve of the Wind turbines in these different propeller pitch angle situations respectively, as we can see from the figure, there is different intersection points in these several curves, the tip-speed ratio that these intersection points are corresponding is respectively a1, a2, b1, b2 and b3, wherein a1, b1 is 0 degree, Cp-λ intersections of complex curve in 1 degree of propeller pitch angle situation, a2, b2 is 1 degree, Cp-λ intersections of complex curve in 2 degree of propeller pitch angle situations, b3 is 2 degree, Cp-λ intersections of complex curve in 3 degree of propeller pitch angle situations.

By the relation between the power of the assembling unit and tip-speed ratio, known, the power of the assembling unit corresponding to the tip-speed ratio that these intersection points are corresponding is respectively pa ₁, pa ₂, pb ₁, pb ₂and pb ₃, wherein pa ₁, pb ₁power of the assembling unit value under present air density corresponding to the intersection point between the power coefficient in 0 degree, 1 degree propeller pitch angle situation and tip-speed ratio curve, pa ₂, pb ₂power of the assembling unit value under present air density corresponding to the intersection point between the power coefficient in 1 degree, 2 degree propeller pitch angle situations and tip-speed ratio curve, pb ₃power of the assembling unit value under present air density corresponding to the intersection point between the power coefficient in 2 degree, 3 degree propeller pitch angle situations and tip-speed ratio curve.

Step S104: judge whether the current power of the assembling unit of described monitoring meets power of the assembling unit setting value, when the described current power of the assembling unit meets described power of the assembling unit setting value, then perform step S105: according to the method preset, the minimum propeller pitch angle that under determining to avoid described blade stall situation, the described current power of the assembling unit is corresponding; When the described current power of the assembling unit does not meet described power of the assembling unit setting value, then perform step S106: judge the described current power of the assembling unit whether in two described power of the assembling unit ranges of set value, if when the described current power of the assembling unit is in two described power of the assembling unit ranges of set value, then perform step S107: the method utilizing interpolation, the minimum propeller pitch angle that under determining to avoid described blade stall situation, the described current power of the assembling unit is corresponding.

In the application, first judge whether the current power of the assembling unit of described monitoring meets power of the assembling unit setting value described in each, when the described current power of the assembling unit meets any one in all described power of the assembling unit setting values, then illustrate that the current power of the assembling unit of now blade is the power of the assembling unit setting value that intersection point between different curve is corresponding, also namely described target shift speed becomes the current power of the assembling unit p=pa of oar Wind turbines _nor p=pb _n, now, the minimum propeller pitch angle that described blade is corresponding when avoiding blade stall is n degree, wherein, and pa _nand pb _npower of the assembling unit value under present air density corresponding to the intersection point between power coefficient corresponding under n-1 degree and n degree propeller pitch angle situation and tip-speed ratio curve, n with n-1 is the different propeller pitch angle of described blade.

When the described current power of the assembling unit judged does not meet described power of the assembling unit setting value, also when namely the described current power of the assembling unit is not equal to any one power of the assembling unit setting value, then judge the described current power of the assembling unit whether in two described power of the assembling unit ranges of set value, also namely the described current power of the assembling unit whether between two power of the assembling unit setting values, if the described current power of the assembling unit is between two power of the assembling unit setting values, then utilize the method for interpolation, the minimum propeller pitch angle corresponding according to described two power of the assembling unit setting values, the minimum propeller pitch angle that under determining to avoid described blade stall situation, the described current power of the assembling unit is corresponding.

Power of the assembling unit value under present air density corresponding to intersection point between the power coefficient in different propeller pitch angle situation and tip-speed ratio curve is pa _{1,2 ... n}, pb _{1,2 ... n}time, wherein, n is the different propeller pitch angle of blade, pa _n, pb _npower of the assembling unit value under present air density corresponding to the intersection point between the power coefficient in n-1 degree, n degree propeller pitch angle situation and tip-speed ratio curve.

The current power of the assembling unit becoming oar wind power generation unit blade in described target shift speed is in pa _n≤ p≤pa _n+1and pb _n>=p>=pb _n+1between time, adopt following interpolation method to determine the minimum propeller pitch angle θ avoiding blade stall:

$\begin{array}{cc}\mathrm{\θ}=n+\frac{p-{\mathrm{pa}}_n}{{\mathrm{pa}}_{n+1}-{\mathrm{pa}}_n}& {\mathrm{pa}}_n\≤p\≤{\mathrm{pa}}_{n+1}\end{array}$

$\begin{array}{cc}\mathrm{\θ}=n+\frac{p-{\mathrm{pa}}_{n+1}}{{\mathrm{pa}}_n-{\mathrm{pa}}_{n+1}}& {\mathrm{pa}}_n\≥p\≥{\mathrm{pa}}_{n+1}\end{array}$

Wherein, pa _nand pb _npower of the assembling unit value under present air density corresponding to the intersection point between power coefficient corresponding under n-1 degree and n degree propeller pitch angle situation and tip-speed ratio curve, pa _n+1and pb _n+1power of the assembling unit value under present air density corresponding to the intersection point between power coefficient corresponding under n+1 degree and n degree propeller pitch angle situation and tip-speed ratio curve, n, n-1 and n+1 are the different propeller pitch angle of described blade.

Below for tip-speed ratio intersection point a1, b1 intersection point in Fig. 3, when tip-speed ratio is within the scope of b1≤λ≤a1, when blade pitch angle is larger, then the angle of attack of vane airfoil profile is less, if when vane airfoil profile is in non-stall conditions, and the less angle of attack is corresponding less lift, then Cp coefficient value is less, otherwise, if vane airfoil profile stall, when blade pitch angle is larger, Cp coefficient is larger, so, when blade pitch angle is 0 degree, when tip-speed ratio is greater than a1 or is less than b1, all there is stall in blade.Therefore, when can determine that tip-speed ratio is a1, b1, the minimum propeller pitch angle of blade stall is avoided to be 1 degree, when tip-speed ratio is a2, b2, avoid the minimum propeller pitch angle of blade stall to be 2 degree, when tip-speed ratio is b3, avoid the minimum propeller pitch angle of blade stall to be 3 degree, within the scope of a1≤λ≤a2, b1 >=λ >=b2 and b2 >=λ >=b3 tip-speed ratio, determine to avoid the minimum propeller pitch angle limits value of blade stall can obtain according to the minimum pitch angle value interpolation of several point of intersection.

This application provides a kind of method determining speed-changing oar-changing wind power generation unit blade controling parameters, Real-Time Monitoring target shift speed becomes the current power of the assembling unit of oar Wind turbines; In different propeller pitch angle situation, determine that target shift speed becomes the curve between the power coefficient of oar Wind turbines and tip-speed ratio; Determine the intersection point between the power coefficient that different propeller pitch angle is corresponding and tip-speed ratio curve, and the power of the assembling unit value under present air density corresponding to intersection point; When the current power of the assembling unit of described monitoring meets described a1≤λ≤a2 power of the assembling unit setting value, then according to presetting method, the minimum propeller pitch angle that under determining to avoid described blade stall situation, the described current power of the assembling unit is corresponding; When the described current power of the assembling unit is in two described power of the assembling unit ranges of set value, utilize the method for interpolation, the minimum propeller pitch angle that under determining to avoid described blade stall situation, the described current power of the assembling unit is corresponding.Can be issued to and avoid blade stall not changing the intrinsic situation of unit, improve the object of unit operation stability and generated energy.

Corresponding with a kind of method determining that the embodiment of the method for speed-changing oar-changing wind power generation unit blade controling parameters provides of above-mentioned the application, see Fig. 4, present invention also provides a kind of system embodiment determining speed-changing oar-changing wind power generation unit blade controling parameters, in the present embodiment, this system comprises:

Monitoring cell 201, becomes the current power of the assembling unit of oar wind power generation unit blade for Real-Time Monitoring target shift speed.

First determining unit 202, in different propeller pitch angle situation, determines that target shift speed becomes the curve between the power coefficient of oar Wind turbines and tip-speed ratio.

Second determining unit 203, for determining the intersection point between the power coefficient that different propeller pitch angle is corresponding and tip-speed ratio curve, and the power of the assembling unit value under present air density corresponding to intersection point.

3rd determining unit 204, for when the current power of the assembling unit of described monitoring meets described power of the assembling unit setting value, then according to presetting method, the minimum propeller pitch angle that under determining to avoid described blade stall situation, the described current power of the assembling unit is corresponding.

4th determining unit 205, for when the described current power of the assembling unit is in two described power of the assembling unit ranges of set value, utilizes the method for interpolation, the minimum propeller pitch angle that under determining to avoid described blade stall situation, the described current power of the assembling unit is corresponding.

This of the present invention's proposition is determined that the method for speed-changing oar-changing wind power generation unit blade parameter is applied on certain 2MW Wind turbines, and the main models parameter of this unit is in table 1:

The main models parameter of table 1. unit

Title	Numerical value	Unit
			Rotor diameter	93	m
Rated speed	15	rpm
			Wind speed round scope	8.3-16.8	rpm
Design year mean wind velocity	7.5	m/s
			Weibull distribution parameters	2	-
Air density	0.9	kg/m 3
			Incision wind speed	3	m/s
Cut-out wind speed	25	m/s

Adopt the inventive method and do not adopt the unit operation Comparative result of the inventive method as shown in Figure 5, Figure 6.As seen from Figure 5, power curve " staying " and " saltus step " phenomenon near rated wind speed adopting the inventive method to obtain unit disappears, theoretical generated energy calculates simultaneously has, annual electricity generating capacity in blade stall situation is 5.934GWh, employing the inventive method avoids the annual electricity generating capacity in blade stall situation to be 5.999GWh, adopts the inventive method generated energy to promote 1.1%.As seen from Figure 6, adopt the inventive method to solve blade stall rear blade resultant bending moment load and reduce, and kurtosis is significantly cut down, these will promote the operation stability of unit.

In sum, a kind of method and system determining speed-changing oar-changing wind power generation unit blade controling parameters that the application provides, can be issued to and avoid blade stall not changing the intrinsic situation of unit, improve the object of unit operation stable type and generated energy.

It should be noted that, each embodiment in this specification all adopts the mode of going forward one by one to describe, and what each embodiment stressed is the difference with other embodiments, between each embodiment identical similar part mutually see.For device class embodiment, due to itself and embodiment of the method basic simlarity, so description is fairly simple, relevant part illustrates see the part of embodiment of the method.

Finally, also it should be noted that, in this article, the such as relational terms of first and second grades and so on is only used for an entity or operation to separate with another entity or control panel, and not necessarily requires or imply the relation that there is any this reality between these entities or operation or sequentially.And, term " comprises ", " comprising " or its any other variant are intended to contain comprising of nonexcludability, thus make to comprise the process of a series of key element, method, article or equipment and not only comprise those key elements, but also comprise other key elements clearly do not listed, or also comprise by the intrinsic key element of this process, method, article or equipment.When not more restrictions, the key element limited by statement " comprising ... ", and be not precluded within process, method, article or the equipment comprising described key element and also there is other identical element.

For convenience of description, various unit is divided into describe respectively with function when describing above device.Certainly, the function of each unit can be realized in same or multiple software and/or hardware when implementing the application.

As seen through the above description of the embodiments, those skilled in the art can be well understood to the mode that the application can add required general hardware platform by software and realizes.Based on such understanding, the technological scheme of the application can embody with the form of software product the part that prior art contributes in essence in other words, this computer software product can be stored in storage medium, as ROM/RAM, magnetic disc, CD etc., comprising some instructions in order to make a computer equipment (can be personal computer, server, or the network equipment etc.) perform the method described in some part of each embodiment of the application or embodiment.

What provide the application above a kind ofly determines that the method and system of speed-changing oar-changing wind power generation unit blade controling parameters are described in detail, apply specific case herein to set forth the principle of the application and mode of execution, the explanation of above embodiment is just for helping method and the core concept thereof of understanding the application; Meanwhile, for one of ordinary skill in the art, according to the thought of the application, all will change in specific embodiments and applications, in sum, this description should not be construed as the restriction to the application.

Claims (4)

1. determine a method for speed-changing oar-changing wind power generation unit blade controling parameters, it is characterized in that, the method comprises:

Real-Time Monitoring target shift speed becomes the current power of the assembling unit of oar Wind turbines;

In different propeller pitch angle situation, determine that target shift speed becomes the curve between the power coefficient of oar Wind turbines and tip-speed ratio; Determine the intersection point between the power coefficient that different propeller pitch angle is corresponding and tip-speed ratio curve, and the power of the assembling unit value under present air density corresponding to intersection point;

$p=\frac{1}{2}\mathrm{\ρ}{C}_p(\mathrm{\β},\mathrm{\λ})\frac{{\mathrm{\ω}}^3{R}^5}{{\mathrm{\λ}}^3}\mathrm{\π}$

In formula, p is the power of the assembling unit, and ρ is air density, C _pfor power coefficient, β is propeller pitch angle, λ tip speed ratio, and ω is wind speed round, and R is wind wheel radius;

When the current power of the assembling unit of described monitoring meets power of the assembling unit setting value, then according to presetting method, the minimum propeller pitch angle that under determining to avoid described blade stall situation, the described current power of the assembling unit is corresponding;

When the described current power of the assembling unit is in two described power of the assembling unit ranges of set value, utilize the method for interpolation, the minimum propeller pitch angle that under determining to avoid described blade stall situation, the described current power of the assembling unit is corresponding.

2. method according to claim 1, is characterized in that, described according to presetting method, and the minimum propeller pitch angle that under determining to avoid described blade stall situation, the described current power of the assembling unit is corresponding is:

The current power of the assembling unit p=pa of oar Wind turbines is become in described target shift speed _nor p=pb _ntime, avoid the minimum propeller pitch angle of blade stall to be n degree;

Wherein, pa _nand pb _npower of the assembling unit value under present air density corresponding to the intersection point between power coefficient corresponding under n-1 degree and n degree propeller pitch angle situation and tip-speed ratio curve, n with n-1 is the different propeller pitch angle of described blade.

3. method according to claim 1, is characterized in that, utilizes the method for interpolation, and the minimum propeller pitch angle that under determining to avoid described blade stall situation, the described current power of the assembling unit is corresponding comprises:

The current power of the assembling unit becoming oar Wind turbines in described target shift speed is in pa _n≤ p≤pa _n+1and pb _n>=p>=pb _n+1between time, adopt following interpolation method to determine the minimum propeller pitch angle θ avoiding blade stall:

$\mathrm{\θ}=n+\frac{p-{\mathrm{pa}}_n}{{\mathrm{pa}}_{n+1}-{\mathrm{pa}}_n}$ pa _n≤p≤pa _n+1

$\mathrm{\θ}=n+\frac{p-{\mathrm{pb}}_{n+1}}{{\mathrm{pb}}_n-{\mathrm{pb}}_{n+1}}$ pb _n≥p≥pb _n+1

Wherein, pa _nand pb _npower of the assembling unit value under present air density corresponding to the intersection point between power coefficient corresponding under n-1 degree and n degree propeller pitch angle situation and tip-speed ratio curve, pa _n+1and pb _n+1power of the assembling unit value under present air density corresponding to the intersection point between power coefficient corresponding under n+1 degree and n degree propeller pitch angle situation and tip-speed ratio curve, n, n-1 and n+1 are the different propeller pitch angle of described blade.

4. determine a system for speed-changing oar-changing wind power generation unit blade controling parameters, it is characterized in that, this system comprises:

Monitoring cell, becomes the current power of the assembling unit of oar Wind turbines for Real-Time Monitoring target shift speed;

First determining unit, in different propeller pitch angle situation, determines that target shift speed becomes the curve between the power coefficient of oar Wind turbines and tip-speed ratio;

Second determining unit, for determining the intersection point between the power coefficient that different propeller pitch angle is corresponding and tip-speed ratio curve, and the power of the assembling unit value under present air density corresponding to intersection point;

3rd determining unit, for when the current power of the assembling unit of described monitoring meets power of the assembling unit setting value, then according to presetting method, the minimum propeller pitch angle that under determining to avoid described blade stall situation, the described current power of the assembling unit is corresponding;

4th determining unit, for when the described current power of the assembling unit is in two described power of the assembling unit ranges of set value, utilizes the method for interpolation, the minimum propeller pitch angle that under determining to avoid described blade stall situation, the described current power of the assembling unit is corresponding.