CN114151275A - Pitch control method for wind turbines - Google Patents

Abstract

Embodiments of the present invention provide a pitch control method for a wind turbine. The pitch control method includes: obtaining the overspeed percentage and the overspeed percentage change rate of the generator speed of the wind turbine; The control method determines an additional pitch rate of the wind turbine. The additional pitch rate of the wind turbine determined by the method is a continuously changing value, so as to ensure that the wind turbine can reduce the tendency of overspeed without causing vibration of the wind turbine and ensure the normal and stable operation of the wind turbine.

Description

Pitch control method for wind turbines

technical field

The invention relates to the technical field of wind power generation, in particular to a pitch control method of a wind power generating set.

Background technique

The blade set of the wind turbine is usually connected to the generator through a speed-increasing gearbox, so that when the wind is small and the blade speed is slow, the speed of the generator is increased through the gearbox to improve the power generation efficiency of the wind turbine; however, in the In catastrophic weather such as hurricanes, the strong wind increases the speed of the blade set, which may cause the generator to rotate too fast. In the case of overspeed, the generator may be overloaded, damaged or even burned, shortening the service life of the wind turbine.

For excessive rotation, it can be alleviated by pitching the wind turbine. The angle of the blade is adjusted according to the wind speed, and the power factor is changed by changing the angle of the blade, that is, the speed and power of the blade are changed, and then the speed and load of the generator are adjusted. The prior art anti-overspeed strategy uses the generator speed and the speed acceleration as reference inputs. Once the generator speed and the speed acceleration reach the corresponding thresholds, a larger rate command is directly superimposed on the pitch angular rate command. The command value is a constant value, so the pitch rate may jump, and the jump may cause the wind turbine to generate a large vibration in one direction, thus threatening the operation safety of the wind turbine.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a pitch control method for a wind turbine, wherein the additional pitch rate of the wind turbine determined by the method is a continuously changing value, so as to ensure that the wind turbine can reduce the tendency of overspeed without It will cause the wind turbine to vibrate and ensure the normal and stable operation of the wind turbine.

In a first aspect, the present invention provides a pitch control method for a wind power generator set, the pitch control method includes: obtaining an overspeed percentage and a change rate of the overspeed percentage of the generator speed of the wind power generator set; based on the obtained wind power The overspeed percentage of the generator speed of the generator set and the rate of change of the overspeed percentage are used to determine the additional pitch rate of the wind turbine by using a fuzzy control method.

Optionally, the pitch control method further includes: controlling the wind turbine to perform a pitch operation based on the determined additional pitch rate of the wind turbine and a predetermined pitch rate.

Optionally, the step of determining the additional pitch rate of the wind turbine by using the fuzzy control method includes: determining the degree of membership of the overspeed percentage of the generator speed of the wind turbine with respect to a preset fuzzy set of overspeed percentages; determining the wind power generation The membership degree of the over-speed percentage change rate of the generator speed of the generator set is related to the preset over-speed percentage change rate fuzzy set; the membership degree of the over-speed percentage based on the generator speed of the wind turbine is related to the preset over-speed percentage fuzzy set And the membership degree of the overspeed percentage change rate of the generator speed of the wind turbine with respect to the preset overspeed percentage change rate fuzzy set, the additional pitch rate of the wind turbine is determined by using the preset fuzzy control rule.

Optionally, the step of determining the degree of membership of the overspeed percentage of the generator speed of the wind turbine with respect to a preset fuzzy set of overspeed percentages includes: based on the overspeed percentage of the generator speed of the wind turbine and the preset overspeed The percentage fuzzy set membership function determines the membership degree of the overspeed percentage of the generator speed of the wind turbine with respect to the preset overspeed percentage fuzzy set.

Optionally, the step of determining the degree of membership of the overspeed percentage change rate of the generator speed of the wind turbine with respect to a preset fuzzy set of the overspeed percentage change rate includes: based on the overspeed percentage change rate of the generator speed of the wind turbine. and a preset overspeed percent change rate fuzzy set membership function to determine the membership degree of the overspeed percent change rate of the generator speed of the wind turbine with respect to the preset overspeed percent change rate fuzzy set.

Optionally, the step of determining the additional pitch rate of the wind turbine by using a preset fuzzy control rule includes: a membership degree of the overspeed percentage with respect to the preset overspeed percentage fuzzy set based on the overspeed percentage of the generator speed of the wind turbine; and The membership degree of the overspeed percentage change rate of the generator speed of the wind turbine with respect to the preset overspeed percentage change rate fuzzy set, by using the preset fuzzy control rules to calculate the additional pitch rate fuzzy with respect to the preset additional pitch rate The membership degree of the set; the additional pitch rate of the wind turbine is calculated based on the preset fuzzy set of additional pitch rates and the membership degree of the additional pitch rate with respect to the preset fuzzy set of additional pitch rates.

Optionally, the preset fuzzy set of additional pitch rates includes a plurality of additional pitch rate values.

Optionally, the step of calculating the additional pitch rate of the wind turbine comprises: by substituting the plurality of additional pitch rate values and the membership degree of the corresponding additional pitch rate with respect to a preset fuzzy set of additional pitch rates into a preset value. The additional pitch rate calculation formula is set to calculate the additional pitch rate of the wind turbine.

Optionally, the preset overspeed percentage fuzzy set membership function includes a normal function.

Optionally, the preset overspeed percent change rate fuzzy set membership function includes a normal function.

In another general aspect, there is provided a pitch control device for a wind turbine, the pitch control comprising: a data acquisition unit configured to obtain an overspeed percentage and an overspeed percentage of a generator rotational speed of the wind turbine A rate of change; an additional pitch rate determination unit configured to determine an additional pitch rate of the wind turbine by using a fuzzy control method based on the acquired overspeed percentage of the generator rotational speed of the wind turbine and the overspeed percentage change rate.

Optionally, the pitch control device further includes: a pitch control unit configured to control the wind turbine to perform a pitch operation based on the determined additional pitch rate of the wind turbine and a predetermined pitch rate.

Optionally, the additional pitch rate determination unit is configured to: determine the degree of membership of the overspeed percentage of the generator speed of the wind turbine with respect to a preset fuzzy set of overspeed percentages; determine the overspeed of the generator speed of the wind turbine. The membership degree of the percentage change rate with respect to the preset overspeed percentage change rate fuzzy set; the membership degree of the overspeed percentage based on the generator speed of the wind turbine with respect to the preset overspeed percentage fuzzy set and the generator speed of the wind turbine The membership degree of the overspeed percentage change rate with respect to the preset overspeed percentage change rate fuzzy set, by using the preset fuzzy control rule to determine the additional pitch rate of the wind turbine.

Optionally, the additional pitch rate determination unit is configured to: determine the overspeed of the generator speed of the wind turbine based on the overspeed percentage of the generator speed of the wind turbine and a preset overspeed percentage fuzzy set membership function. Percentage of membership to a preset fuzzy set of overspeed percentages.

Optionally, the additional pitch rate determination unit is further configured to: determine the generator of the wind turbine based on the overspeed percentage change rate of the generator speed of the wind turbine and the preset overspeed percentage change rate fuzzy set membership function. The membership degree of the overspeed percentage change rate of the rotational speed relative to the preset overspeed percentage change rate fuzzy set.

Optionally, the additional pitch rate determination unit is configured to: based on the membership of the overspeed percentage of the generator speed of the wind turbine with respect to the preset overspeed percentage fuzzy set and the overspeed percentage of the generator speed of the wind turbine The membership degree of the change rate with respect to the preset overspeed percentage change rate fuzzy set is calculated by using a preset fuzzy control rule to calculate the membership degree of the additional pitch rate with respect to the preset additional pitch rate fuzzy set; The additional pitch rate of the wind turbine is calculated with respect to the membership of the fuzzy set of the pitch rate and the additional pitch rate with respect to the preset fuzzy set of the additional pitch rate.

Optionally, the preset fuzzy set of additional pitch rates includes a plurality of additional pitch rate values.

Optionally, the additional pitch rate determination unit is configured to: by substituting the membership degrees of the plurality of additional pitch rate values and the corresponding additional pitch rates with respect to the preset additional pitch rate fuzzy set into the preset additional pitch rate. The pitch rate calculation formula is used to calculate the additional pitch rate of the wind turbine.

Optionally, the preset overspeed percentage fuzzy set membership function includes a normal function.

Optionally, the preset overspeed percent change rate fuzzy set membership function includes a normal function.

In another general aspect, there is provided a computer-readable storage medium storing a computer program that, when executed by a processor, implements the pitch control method as described above.

In another general aspect, there is provided a controller of a wind turbine, the controller comprising: a processor; and a memory storing a computer program that, when executed by the processor, implements the above-mentioned Pitch control method.

In the pitch control method for wind turbines and the pitch control device for wind turbines according to the embodiments of the present invention, the determined additional pitch rate of the wind turbines is a continuously changing value, thereby ensuring that the wind turbines can reduce excessive It will not cause the vibration of the wind turbine to ensure the normal and stable operation of the wind turbine.

Additional aspects and/or advantages of the present disclosure will be set forth in part in the description that follows, and in part will be apparent from the description, or may be learned by practice of the present disclosure.

Description of drawings

The above and other objects and features of exemplary embodiments of the present disclosure will become more apparent from the following description taken in conjunction with the accompanying drawings that exemplarily illustrate embodiments, wherein:

Fig. 1 is the overall architecture of fuzzy control according to an embodiment of the present invention;

2 is a flowchart of a pitch control method according to an embodiment of the present invention;

3 is a simulation result of an additional pitch rate according to an embodiment of the present invention;

4 is a block diagram of a pitch control device according to an embodiment of the present invention;

5 is a block diagram of a controller of a wind power plant according to an embodiment of the present disclosure.

Description of reference numbers:

1-speed processing unit, 2-fuzzy control logic, 400-pitch control device, 410-data acquisition unit, 420-additional pitch rate determination unit, 500-controller, 510-processor, 520-memory.

Detailed ways

The following detailed description is provided to assist the reader in gaining a comprehensive understanding of the methods, apparatus and/or systems described herein. However, various changes, modifications and equivalents of the methods, apparatus and/or systems described herein will be apparent upon understanding of the disclosure of the present application. For example, the orders of operations described herein are examples only, and are not limited to those orders set forth herein, except that operations must occur in a particular order, as will be apparent upon understanding the disclosure of this application That was changed. Furthermore, descriptions of features known in the art may be omitted for increased clarity and conciseness.

The features described herein may be implemented in different forms and should not be construed as limited to the examples described herein. Rather, the examples described herein have been provided to illustrate but a few of the many possible ways of implementing the methods, devices and/or systems described herein, which would be after an understanding of the disclosure of the present application. clearly.

As used herein, the term "and/or" includes any one and any combination of any two or more of the associated listed items.

Although terms such as “first,” “second,” and “third” may be used herein to describe various elements, components, regions, layers or sections, these elements, components, regions, layers or sections should not be restricted by these terms. Rather, these terms are only used to distinguish one element, component, region, layer or section from another element, component, region, layer or section. Thus, reference to a first member, first component, first region, first layer or first portion in the examples described herein could also be termed a second member, second member, first layer or first portion without departing from the teachings of the examples. Component, second area, second layer or second section.

In the specification, when an element such as a layer, region or substrate is described as being "on", "connected to" or "coupled to" another element, the element can be directly "on" the other element "connected" or "coupled to" another element directly, or one or more other elements may be intervening. In contrast, when an element is described as being "directly on," "directly connected to," or "directly coupled to" another element, there may be no intervening elements present.

The terminology used herein is used to describe various examples only and is not to be used to limit the disclosure. The singular forms are also intended to include the plural forms unless the context clearly dictates otherwise. The terms "comprising", "including" and "having" indicate the presence of the recited features, quantities, operations, components, elements, and/or combinations thereof, but do not preclude the presence or addition of one or more other features, numbers, operations, components , elements and/or combinations thereof.

Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs after understanding the disclosure. Unless explicitly so defined herein, terms (such as those defined in a general dictionary) should be construed to have meanings consistent with their meanings in the context of the relevant art and this disclosure, and should not be idealized or Explain too formally.

Also, in the description of examples, detailed descriptions of well-known related structures or functions will be omitted when it is considered that such detailed descriptions would cause obscure interpretation of the present disclosure.

Hereinafter, the embodiments will be described in detail with reference to the accompanying drawings. However, embodiments may be implemented in various forms and are not limited to the examples described herein.

The pitch control method of the wind turbine in the embodiment of the present invention uses the fuzzy control method to obtain the continuously changing additional pitch rate based on the rotational speed information of the fan and the information of the change rate thereof.

The fan speed information and its change rate information on which the fuzzy control method used in the present invention is based are introduced below. In the pitch control method of the present invention, the fan speed information refers to the overspeed percentage of the generator speed, the overspeed percentage=[(current speed-rated speed)/rated speed]×100%, and the corresponding change rate information refers The rate of change of the overspeed percentage.

Traditionally, the generator speed is the filtered speed of the pitch loop. After passing through several filters, especially the second-order low-pass filter and the tower filter, the generator speed lag is relatively serious. For the extreme gust of 1.4, the generator speed rises slowly after filtering when the gust comes, delaying the delay. The time for the anti-overspeed function to intervene; at the same time, after the gust passes, when the actual generator speed has dropped, the additional pitch rate will still provide a larger value, which will cause the generator speed to drop too fast, causing the tower top component load at this stage. larger. To solve this problem, consider using an asymmetric moving average to process the generator speed. When the speed rises, a 3s time constant is used to perform a moving average of the generator speed, and when the speed decreases, a 0.2s time constant is used to perform a moving average of the generator speed, thereby assisting the unit to quickly reduce the additional pitch when the generator speed drops. rate.

FIG. 1 is an overall architecture of fuzzy control according to an embodiment of the present invention. As shown in Figure 1, the overall architecture of fuzzy control includes a generator speed processing unit 1 and a fuzzy control logic 2, wherein the generator speed processing unit 1 calculates and outputs the input current generator speed as the overspeed percentage of the generator speed and the overspeed percentage change rate, then the calculated overspeed percentage of generator speed and the overspeed percentage change rate are input into fuzzy control logic 2, which is based on the overspeed percentage of generator speed and the overspeed percentage change rate , by using the fuzzy control method to determine the additional pitch rate of the wind turbine, and then control the wind turbine to perform the pitch operation based on the determined additional pitch rate of the wind turbine and the predetermined pitch rate. However, the present invention is not limited to this. The fuzzy control logic can provide the determined additional pitch rate of the wind turbine to the pitch controller, and then the pitch controller can control the wind turbine to execute the pitch based on the additional pitch rate of the wind turbine and the predetermined pitch rate. Paddle operation. In principle, when the overspeed percentage and the overspeed percentage change rate are both greater than 0, the calculation of the additional pitch rate begins.

FIG. 2 is a flowchart illustrating a pitch control method according to an embodiment of the present invention.

Referring to FIG. 2 , in step S201 , the overspeed percentage and the rate of change of the overspeed percentage of the generator speed of the wind turbine are obtained. According to the embodiments of the present invention, the generator speed can be obtained in various ways, and then the overspeed percentage and the overspeed percentage change rate of the generator speed can be determined.

In step S202, based on the acquired overspeed percentage of the generator rotational speed of the wind turbine and the rate of change of the overspeed percentage, the additional pitch rate of the wind turbine is determined by using a fuzzy control method. Compared with the prior art in which the pitch rate jumps, the additional pitch rate of the wind turbine determined by the fuzzy control method is continuously changed, so that the operation of the wind turbine is stable and safe.

Optionally, after the additional pitch rate of the wind turbine is determined, the wind turbine may be controlled to perform a pitch operation based on the determined additional pitch rate of the wind turbine and the predetermined pitch rate.

Specifically, in step S202, the membership degree of the overspeed percentage of the generator rotational speed of the wind turbine with respect to the preset fuzzy set of overspeed percentages may be determined first, and then the overspeed percentage change of the generator rotational speed of the wind turbine may be determined The membership degree of the fuzzy set of the rate with respect to the preset overspeed percentage change rate, and finally the membership degree of the fuzzy set based on the overspeed percentage of the generator speed of the wind turbine with respect to the preset overspeed percentage and the generator speed of the wind turbine. The membership of the overspeed percent change rate with respect to a preset fuzzy set of the overspeed percent change rate is determined by using a preset fuzzy control rule to determine the additional pitch rate of the wind turbine. As described above, it may be determined that the overspeed percentage of the generator speed of the wind turbine is fuzzy with respect to the preset overspeed percentage based on the overspeed percentage of the generator speed of the wind turbine and the preset overspeed percentage fuzzy set membership function Membership of the set. In addition, based on the overspeed percentage change rate of the generator rotational speed of the wind turbine and the preset overspeed percentage change rate fuzzy set membership function, it may be determined that the overspeed percentage change rate of the generator rotational speed of the wind turbine is related to the preset overspeed percentage change rate. Membership of the fuzzy set of overspeed percent change rate. The preset overspeed percent fuzzy set membership function may include a normal function, and the preset overspeed percent change rate fuzzy set membership function includes a normal function.

According to an embodiment of the present invention, in the step of determining the additional pitch rate of the wind turbine by using a preset fuzzy control rule, it may be fuzzy with respect to the preset overspeed percentage based on the overspeed percentage of the generator rotational speed of the wind turbine. The membership degree of the set and the overspeed percentage change rate of the generator speed of the wind turbine with respect to the preset overspeed percentage change rate The membership degree of the fuzzy set is calculated by using the preset fuzzy control rules to calculate the additional pitch rate with respect to the preset overspeed percentage change rate Membership of the fuzzy set of additional pitch rates. Then, the additional pitch rate of the wind turbine may be calculated based on the preset fuzzy set of additional pitch rates and the membership of the additional pitch rate with respect to the preset fuzzy set of additional pitch rates. Here, as described above, the preset fuzzy set of additional pitch rates includes a plurality of additional pitch rate values. Therefore, the wind turbine can be calculated by substituting the plurality of additional pitch rate values and the membership degrees of the corresponding additional pitch rates with respect to the preset additional pitch rate fuzzy set into the preset additional pitch rate calculation formula The additional pitch rate of .

The following example illustrates the method for calculating the additional pitch rate. Specifically, in the step of determining the additional pitch rate of the wind turbine by using the fuzzy control method, the membership degree of the overspeed percentage of the generator rotational speed of the wind turbine with respect to the preset overspeed percentage fuzzy set is determined, and the wind turbine is determined The membership degree of the overspeed percentage change rate of the generator speed of the generator set with respect to the preset overspeed percentage change rate fuzzy set. For example, the fuzzy sets of the overspeed percentage and overspeed percentage change rate of the generator can be defined as {PL _p , PM _p , PS _p , ZE _p }, {PL _ω , PM _ω , PS _ω , ZE _ω }, respectively, where , {PL _p , PM _p , PS _p , ZE _p } includes four elements PL _p , PM _p , PS _p , ZE _p , each element itself can also be a small set, PL _p represents the generator speed overspeed percentage Larger, PM _p means the generator speed overspeed percentage is medium, PS _p means the generator speed overspeed percentage is small, ZE _p means the generator speed overspeed percentage is close to zero; similarly, {PL _ω , PM _ω , PS _ω , ZE _ω } includes four elements PL _ω , PM _ω , PS _ω , ZE _ω , each element itself can also be a small set, PL _ω indicates that the generator speed overspeed percentage change rate is large, PM _ω indicates that the generator The percentage change rate of the overspeed speed is medium, PS _ω indicates that the percentage change rate of the generator speed overspeed is small, and ZE _ω indicates that the percentage change rate of the generator speed overspeed is close to zero. The above fuzzy sets of the generator speed overspeed percentage and the overspeed percentage change rate include four elements, which respectively indicate that the generator speed overspeed percentage and the overspeed percentage change rate are relatively large, medium, small and close to zero, but the present invention Not limited to this, the fuzzy set defined above is only an example, and those skilled in the art can define more elements according to the actual situation, for example, can define 3, 5, 6, 7, 8 or more elements , to divide the generator speed overspeed percentage and the overspeed percentage change rate into more intervals to represent the corresponding number of evaluation results. The following description will be based on fuzzy sets {PL _p , PM _p , PS _p , ZE _p }, {PL _ω , PM _ω , PS _ω , ZE _ω } with four elements.

Next, in order to determine the degree of membership of the overspeed percentage of the generator speed of the wind turbine with respect to the preset overspeed percentage fuzzy set and to determine the overspeed percentage change rate of the generator speed of the wind turbine with respect to the preset overspeed percentage The membership degree of the fuzzy set of the rate of change is based on the overspeed percentage of the generator speed of the wind turbine and the preset overspeed percentage fuzzy set membership function to determine the overspeed percentage of the generator speed of the wind turbine with respect to the preset overspeed. The membership degree of the speed percentage fuzzy set, and based on the overspeed percentage change rate of the generator speed of the wind turbine generator set and the preset overspeed percentage change rate fuzzy set membership function, the overspeed percentage of the generator speed of the wind turbine generator set is determined. The membership of the rate-of-change fuzzy set with respect to the preset overspeed percentage rate-of-change. For example, define the membership function of the generator speed overspeed percentage and the overspeed percentage change rate respectively with respect to the above-defined generator speed overspeed percentage fuzzy set and the overspeed percentage change rate fuzzy set to determine the generator speed overspeed percentage, respectively and the overspeed percentage change rate with respect to the membership of the generator speed overspeed percentage fuzzy set and the overspeed percentage change rate fuzzy set.

In this embodiment, the membership functions of the above two sets are defined as normal functions, that is,

However, it is not limited thereto, and the above membership functions are only examples. In the present invention, various membership functions can be defined according to various engineering applications, and different membership functions can be respectively defined for the above two sets.

In the normal membership function defined above, x represents the current generator speed overspeed percentage or the rate of change of the overspeed percentage, a and b are vectors corresponding to the fuzzy sets, μ _A represents the current generator speed overspeed percentage or The membership of the overspeed percentage rate of change with respect to the corresponding fuzzy set. For the fuzzy set of generator speed overspeed percentage, a is a specific example of the fuzzy set {PL _p , PM _p , PS _p , ZE _p } defined according to engineering experience or expert database. Specifically, the average value of each element in {PL _p , PM _p , PS _p , ZE _p } can be taken, for example, a=[15, 10, 5, 0]. According to this example, the average value of the element PL _p is 15, that is, the generator speed overspeed percentage is 15%, which means that the threshold value of 15% is defined as a large generator speed overspeed percentage, and the average value of the element PM _p is 10, that is The generator speed overspeed percentage is 10%, which means that the threshold 10% is defined as the generator speed overspeed percentage medium, and the average value of the element PS _p is 5, that is, the generator speed overspeed percentage is 5%, which means that the threshold value is 5%. Defined as the generator speed overspeed percentage is small, the average value of the element ZE _p is 0, that is, the generator speed overspeed percentage is 0%, which means that the threshold 0% is defined as the generator speed overspeed percentage close to zero. However, the present invention is not limited thereto, a=[15, 10, 5, 0] is only an example, and those skilled in the art can define a as other numerical vectors according to practical engineering applications. b is the variance of each element in the set, for example b=[5, 5, 5, 5], indicating that the variance of each element PL _p , PM _p , PS _p , ZE _p itself is 5, but not limited to this, this Those skilled in the art can define b as other numerical vectors according to practical engineering applications.

结果为0.0183。同理可得，隶属于PM_p的隶属度

为0.3679，隶属于PS_p的隶属度

为1，隶属于ZE_p的隶属度

为0.3679。即，通过上述步骤，得到风力发电机组的发电机转速的过速百分比关于预设的过速百分比模糊集合的隶属度。Assuming that the current generator speed overspeed percentage is 5%, then according to the membership function, the membership of this value to PL _p is

The result is 0.0183. In the same way, the degree of membership of PM _p

is 0.3679, which belongs to the membership degree of PS _p

is 1, which belongs to the membership degree of ZE _p

is 0.3679. That is, through the above steps, the membership degree of the over-speed percentage of the generator rotational speed of the wind turbine generator relative to the preset over-speed percentage fuzzy set is obtained.

即，通过上述步骤，得到风力发电机组的发电机转速的过速百分比变化率关于预设的过速百分比变化率模糊集合的隶属度。Similarly, for the fuzzy set of generator overspeed percentage change rate, a=[5, 3, 1.5, 0], b=[1, 2, 2, 2] can be defined, and the current generator can be calculated in the same way The membership value of each element in the fuzzy set about the percentage change rate of the speed overspeed

That is, through the above steps, the membership degree of the overspeed percentage change rate of the generator rotational speed of the wind power generating set relative to the preset overspeed percentage change rate fuzzy set is obtained.

Next, change the degree of membership of the fuzzy set based on the overspeed percentage of the generator speed of the wind turbine with respect to the preset overspeed percentage and the overspeed percentage change rate of the generator speed of the wind turbine with respect to the preset overspeed percentage The membership degree of the rate fuzzy set is used to determine the additional pitch rate of the wind turbine by using the preset fuzzy control rules.

Specifically, first, an additional pitch rate fuzzy set {PL _out , PM _out , PS _out , ZE _out } of the wind turbine is similarly defined, wherein {PL _out , PM _out , PS _out , ZE _out } includes four Elements PL _out , PM _out , PS _out , ZE _out , each element itself can also be a small set, PL _out indicates that the additional pitch rate is relatively large, PM _out indicates that the additional pitch rate is medium, and PS _out indicates the additional pitch rate Smaller, ZE _out means the additional pitch rate is close to zero. The above fuzzy set of additional pitch rate includes four elements, but the present invention is not limited to this, the fuzzy set defined above is only an example, and those skilled in the art can define more elements according to the actual situation, for example, can define three, 5, 6, 7, 8 or more elements to divide the additional pitch rate into more intervals to represent the corresponding number of evaluation results. The following description will be based on fuzzy sets {PL _out , PM _out , PS _out , ZE _out } with four elements.

When actually calculating the additional pitch rate, the average value of each element in {PL _out , PM _out , PS _out , ZE _out } can be taken, for example, {PL _out , PM _out , PS _out , ZE _out } can take specific values is [2.5, 0.75, 0.15, 0], indicating that the average value of the element PL _out is 2.5°/s, that is, the additional pitch rate is 2.5°/s, which is defined as the larger additional pitch rate, the average value of PM _out is 0.75°/s, that is, the additional pitch rate is 0.75°/s, which is defined as the medium additional pitch rate, and the average value of PS _out is 0.15°/s, that is, the additional pitch rate is 0.15°/s, which is defined as the additional pitch rate. The pitch rate is small, and the average value of ZE _out is 0°/s, that is, the additional pitch rate is 0°/s, which is defined as the additional pitch rate close to zero. However, the present invention is not limited to this, and {PL _out , PM _out , PS _out , ZE _out } may take any other specific values. For example, those skilled in the art can define {PL _out , PM _out , PS _out , ZE _out } as other values according to practical engineering applications. Similarly, define the membership degree of the additional pitch rate to PL _out as PL _r , define the membership degree of the additional pitch rate to PM _out as PM _r , and define the membership degree of the additional pitch rate to PS _out As PS _r , the membership degree of the additional pitch rate belonging to ZE _out is defined as ZE _r , that is, the membership degree set of the additional pitch rate is {PL _r , PM _r , PS _r , ZE _r }.

In the step of determining the additional pitch rate of the wind turbine by using the preset fuzzy control rules, the fuzzy control rules are defined. For example, according to the characteristic curve of the wind turbine, the following fuzzy control rules can be obtained:

且发电机过速百分比隶属于PS_p的隶属度为

则附加变桨速率隶属于PL_out的隶属度PL_r1为

其中，

表示

和

中的最小者，以下相同；1. If the percentage change rate of generator overspeed belongs to PL _ω , the membership degree is

And the degree of membership of the generator overspeed percentage to PS _p is

Then the membership degree PL _r1 of the additional pitch rate belonging to PL _out is

in,

express

and

The smallest of , the following are the same;

且发电机过速百分比隶属于ZE_p的隶属度为

则附加变桨速率隶属于PL_out的隶属度PL_r2为

2. If the percentage change rate of generator overspeed belongs to PL _ω , the membership degree is

And the degree of membership of the generator overspeed percentage to ZE _p is

Then the membership degree PL _r2 of the additional pitch rate belonging to PL _out is

且发电机过速百分比隶属于PL_p的隶属度为

则附加变桨速率隶属于PM_out的隶属度PM_r1为

3. If the percentage change rate of generator overspeed belongs to PL _ω , the membership degree is

And the degree of membership of the generator overspeed percentage to PL _p is

Then the membership degree PM _r1 of the additional pitch rate belonging to PM _out is

且发电机过速百分比隶属于PM_p的隶属度为

则附加变桨速率隶属于PM_out的隶属度PM_r2为

4. If the percentage change rate of generator overspeed belongs to PL _ω , the membership degree is

And the degree of membership of the generator overspeed percentage to PM _p is

Then the membership degree PM _r2 of the additional pitch rate belonging to PM _out is

且发电机过速百分比隶属于PS_p的隶属度为

则附加变桨速率隶属于PM_out的隶属度PM_r3为

5. If the percentage change rate of generator overspeed belongs to PM _ω , the membership degree is

And the degree of membership of the generator overspeed percentage to PS _p is

Then the membership degree PM _r3 of the additional pitch rate belonging to PM _out is

且发电机过速百分比隶属于PL_p的隶属度为

则附加变桨速率隶属于PS_out的隶属度PS_r1为

6. If the percentage change rate of generator overspeed belongs to PM _ω , the membership degree is

And the degree of membership of the generator overspeed percentage to PL _p is

Then the membership degree PS _r1 of the additional pitch rate belonging to PS _out is

且发电机过速百分比隶属于PM_p的隶属度为

则附加变桨速率隶属于PS_out的隶属度PS_r2为

7. If the percentage change rate of generator overspeed belongs to PM _ω , the membership degree is

And the degree of membership of the generator overspeed percentage to PM _p is

Then the membership degree PS _r2 of the additional pitch rate belonging to PS _out is

且发电机过速百分比隶属于ZE_p的隶属度为

则附加变桨速率隶属于PS_out，并且隶属度PS_r3为

8. If the percentage change rate of generator overspeed belongs to PM _ω , the membership degree is

And the degree of membership of the generator overspeed percentage to ZE _p is

Then the additional pitch rate belongs to PS _out , and the degree of membership PS _r3 is

且发电机过速百分比隶属于PM_p的隶属度为

则附加变桨速率隶属于PS_out，并且隶属度PS_r4为

9. If the percentage change rate of generator overspeed belongs to PS _ω , the membership degree is

And the degree of membership of the generator overspeed percentage to PM _p is

Then the additional pitch rate belongs to PS _out , and the degree of membership PS _r4 is

且发电机过速百分比隶属于PS_p的隶属度为

则附加变桨速率隶属于PS_out的隶属度PS_r5为

10. If the percentage change rate of generator overspeed belongs to PS _ω , the membership degree is

And the degree of membership of the generator overspeed percentage to PS _p is

Then the membership degree PS _r5 of the additional pitch rate belonging to PS _out is:

且发电机过速百分比隶属于PL_p的隶属度为

则附加变桨速率隶属于ZE_out的隶属度ZE_r1为

11. If the percentage change rate of generator overspeed belongs to PS _ω , the membership degree is

And the degree of membership of the generator overspeed percentage to PL _p is

Then the membership degree ZE _r1 of the additional pitch rate belonging to ZE _out is:

且发电机过速百分比隶属于ZE_p的隶属度为

则附加变桨速率隶属于ZE_out的隶属度ZE_r2为

12. If the percentage change rate of generator overspeed belongs to PS _ω , the membership degree is

And the degree of membership of the generator overspeed percentage to ZE _p is

Then the membership degree ZE _r2 of the additional pitch rate belonging to ZE _out is

且发电机过速百分比隶属于PL_p的隶属度为

则附加变桨速率隶属于ZE_out的隶属度ZE_r3为

13. If the percentage change rate of generator overspeed belongs to ZE _ω , the membership degree is

And the degree of membership of the generator overspeed percentage to PL _p is

Then the membership degree ZE _r3 of the additional pitch rate belonging to ZE _out is:

且发电机过速百分比隶属于PM_p的隶属度为

则附加变桨速率隶属于ZE_out的隶属度ZE_r4为

14. If the percentage change rate of generator overspeed belongs to ZE _ω , the membership degree is

And the degree of membership of the generator overspeed percentage to PM _p is

Then the membership degree ZE _r4 of the additional pitch rate belonging to ZE _out is

且发电机过速百分比隶属于PS_p的隶属度为

则附加变桨速率隶属于ZE_out的隶属度ZE_r5为

15. If the percentage change rate of generator overspeed belongs to ZE _ω , the membership degree is

And the degree of membership of the generator overspeed percentage to PS _p is

Then the membership degree ZE _r5 of the additional pitch rate belonging to ZE _out is:

且发电机过速百分比隶属于ZE_p的隶属度为

则附加变桨速率隶属于ZE_out的隶属度ZE_r6为

16. If the percentage change rate of generator overspeed belongs to ZE _ω , the membership degree is

And the degree of membership of the generator overspeed percentage to ZE _p is

Then the membership degree ZE _r6 of the additional pitch rate belonging to ZE _out is:

That is, according to the different membership degrees of the overspeed percentage to the fuzzy set of the overspeed percentage and the different membership degrees of the overspeed percentage change rate to the fuzzy set of the overspeed percentage change rate, the different membership degrees of the additional pitch rate to the fuzzy set of the additional pitch rate are obtained. , where, in each fuzzy control rule, the obtained membership degree of the additional pitch rate with respect to the fuzzy set of the additional pitch rate is the membership degree of the overspeed percentage with respect to the fuzzy set of the overspeed percentage and the rate of change of the overspeed percentage with respect to the overspeed The smallest of the membership degrees of the fuzzy sets of percentage change rates, so as to obtain different numbers of membership degrees of the additional pitch rate with respect to the corresponding additional pitch rate fuzzy sets, and the final additional pitch rate membership is the sum of the corresponding membership degrees. Maximum, ie, PL _r =max[PL _r1 , PL _r2 ], PM _r =max[PM _r1 , PM _r2 , PM _r3 ], PS _r =max[PS _r1 , PS _r2 , PS _r3 , PS _r4 , PS _r5 ], ZE _r =max[ZE _r1 , ZE _r2 , ZE _r3 , ZE _r4 , ZE _r5 , ZE _r6 ], the membership set of the additional pitch rate is finally obtained as {PL _r , PM _r , PS _r , ZE _r }. However, the above fuzzy control rules are only examples, and the present invention is not limited thereto. Those skilled in the art can design other fuzzy control rules according to actual needs.

Then, an additional pitch rate of the wind turbine is calculated based on the preset fuzzy set of additional pitch rates and the membership of the additional pitch rates with respect to the preset fuzzy set of additional pitch rates, for example, by combining the plurality of additional pitch rates The velocity value and the membership degree of the corresponding additional pitch rate with respect to the preset additional pitch rate fuzzy set are substituted into the preset additional pitch rate calculation formula to calculate the additional pitch rate of the wind turbine. Specifically, the specific values of the fuzzy set of additional pitch rates {PL _out , PM _out , PS _out , ZE _out } and the membership degree set of additional pitch rates {PL _r , PM _r , PS _r , ZE _r } are substituted into the formula

Get the final additional pitch rate.

Fig. 3 shows the simulation result of the additional pitch rate according to the embodiment of the present invention, wherein input1 is the generator overspeed percentage [%], input2 is the generator overspeed percentage change rate, and output1 is the additional pitch rate [°/ s], as can be seen from FIG. 3 , according to the pitch control method of the wind turbine according to the embodiment of the present invention, the obtained additional pitch rate of the wind turbine is a continuously changing value. That is, compared with the prior art in which the pitch rate jumps, the additional pitch rate of the wind turbine determined by using the fuzzy control method is a continuously changing value, which ensures that the turbine can reduce the tendency of overspeed on the one hand, and at the same time does not It will cause the unit to vibrate and ensure the normal and stable operation of the unit.

FIG. 4 is a block diagram illustrating a pitch control apparatus according to an embodiment of the present invention.

Referring to FIG. 4 , the pitch control apparatus 400 may include a data acquisition unit 410 and an additional pitch rate determination unit 420 . The data acquisition unit 410 may acquire the overspeed percentage and the overspeed percentage change rate of the generator rotational speed of the wind turbine. The additional pitch rate determination unit 420 may determine the additional pitch rate of the wind turbine by using a fuzzy control method based on the acquired overspeed percentage and the overspeed percentage change rate of the generator rotational speed of the wind turbine.

Optionally, the pitch control device 400 may further include a pitch control unit (not shown). The pitch control unit may control the wind turbine to perform a pitch operation based on the determined additional pitch rate of the wind turbine and the predetermined pitch rate.

Specifically, the additional pitch rate determination unit 420 may determine the degree of membership of the overspeed percentage of the generator rotational speed of the wind turbine with respect to a preset fuzzy set of overspeed percentages, and may determine the overspeed percentage of the generator rotational speed of the wind turbine. rate of change membership of the fuzzy set of rates of change with respect to preset overspeed percentages and may be based on membership of the overspeed percentage of the wind turbine generator speed with respect to the preset overspeed percentage fuzzy set and the generators of the wind turbine The membership degree of the overspeed percentage change rate of the rotational speed with respect to the preset overspeed percentage change rate fuzzy set, and the additional pitch rate of the wind turbine is determined by using a preset fuzzy control rule. Here, the additional pitch rate determination unit 420 may determine, based on the overspeed percentage of the generator rotational speed of the wind turbine and the preset overspeed percentage fuzzy set membership function, that the overspeed percentage of the generator rotational speed of the wind turbine is related to the preset The membership of the fuzzy set of overspeed percentages. On the other hand, the additional pitch rate determination unit 420 may determine the generator rotational speed of the wind turbine based on the overspeed percentage change rate of the generator rotational speed of the wind turbine and the preset overspeed percentage change rate fuzzy set membership function. The membership of the overspeed percent change rate with respect to the preset overspeed percent change rate fuzzy set.

Further, the additional pitch rate determination unit 420 may be based on the membership degree of the overspeed percentage of the generator speed of the wind turbine with respect to the preset overspeed percentage fuzzy set and the overspeed percentage change rate of the generator speed of the wind turbine with respect to The membership degree of the preset overspeed percentage change rate fuzzy set, by using the preset fuzzy control rules to calculate the membership degree of the additional pitch rate with respect to the preset additional pitch rate fuzzy set, and then can be based on the preset additional pitch rate The membership degree of the fuzzy set The fuzzy set of rates and the additional pitch rate calculate the additional pitch rate of the wind turbine with respect to the membership of the preset fuzzy set of additional pitch rates. As described above, the preset fuzzy set of additional pitch rates includes a plurality of additional pitch rate values. Therefore, the additional pitch rate determination unit 420 may calculate the additional pitch rate by substituting the plurality of additional pitch rate values and the membership degrees of the corresponding additional pitch rates with respect to the preset additional pitch rate ambiguous set into the preset additional pitch rate formula to calculate the additional pitch rate of the wind turbine.

5 is a block diagram illustrating a controller of a wind turbine according to an embodiment of the present disclosure.

Referring to FIG. 5 , the controller 500 of the wind turbine according to an embodiment of the present disclosure may be, but is not limited to, a pitch controller, a main controller of the wind turbine, and the like. The controller 500 of the wind turbine according to an embodiment of the present disclosure may include a processor 510 and a memory 520 . The processor 510 may include, but is not limited to, a central processing unit (CPU), a digital signal processor (DSP), a microcomputer, a field programmable gate array (FPGA), a system on a chip (SoC), a microprocessor, an application specific integrated circuit (ASIC) etc. The memory 520 stores computer programs to be executed by the processor 510 . Memory 920 includes high-speed random access memory and/or non-volatile computer-readable storage media. When the processor 510 executes the computer program stored in the memory 520, the pitch control method as described above can be implemented.

Optionally, the controller 500 may communicate with other various components in the wind turbine by wired/wireless communication, and may also communicate with other devices in the wind farm by wired/wireless communication. In addition, the controller 500 may communicate with devices outside the wind farm in a wired/wireless communication manner.

The pitch control method for a wind turbine according to an embodiment of the present disclosure may be written as a computer program and stored on a computer-readable storage medium. When the computer program is executed by the processor, the above-mentioned screen recording method can be implemented. Examples of computer-readable storage media include: read only memory (ROM), random access programmable read only memory (PROM), electrically erasable programmable read only memory (EEPROM), random access memory (RAM), dynamic Random Access Memory (DRAM), Static Random Access Memory (SRAM), Flash, Non-Volatile Memory, CD-ROM, CD-R, CD+R, CD-RW, CD+RW, DVD-ROM, DVD -R, DVD+R, DVD-RW, DVD+RW, DVD-RAM, BD-ROM, BD-R, BD-R LTH, BD-RE, Blu-ray or Optical Disc storage, Hard Disk Drive (HDD), Solid State Drive ( SSD), card memory (such as Multimedia Card, Secure Digital (SD) card or Extreme Digital (XD) card), magnetic tape, floppy disk, magneto-optical data storage device, optical data storage device, hard disk, solid state disk, and any other device , said any other apparatus is configured to store a computer program and any associated data, data files and data structures in a non-transitory manner and to provide said computer program and any associated data, data files and data structures to processing A processor or computer enables the processor or computer to execute the computer program. In one example, a computer program and any associated data, data files and data structures are distributed over networked computer systems such that the computer program and any associated data, data files and data structures are processed by one or more processors or Computers store, access, and execute in a distributed fashion.

According to the pitch control method of the wind turbine according to the exemplary embodiment of the present disclosure, the additional pitch rate that can be continuously changed can be calculated by calculating the fan speed and its change rate information, which can effectively reduce the probability of the overspeed of the turbine and improve the pre-failure of the turbine. Mean time before faults (MTBF, mean time before faults), as well as the power generation of the unit, while bringing less disturbance to the unit and improving the operating stability of the unit.

The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited to this. The combination should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims (13)

1. A variable pitch control method of a wind generating set is characterized by comprising the following steps:

acquiring overspeed percentage and overspeed percentage change rate of generator rotation speed of a wind generating set;

and determining the additional pitch rate of the wind generating set by using a fuzzy control method based on the obtained overspeed percentage and the overspeed percentage change rate of the generator rotating speed of the wind generating set.

2. The pitch control method of claim 1, further comprising:

and controlling the wind generating set to perform a pitching operation based on the determined additional pitching speed of the wind generating set and the preset pitching speed.

3. The pitch control method of claim 1, wherein the step of determining the additional pitch rate of the wind turbine generator set by using a fuzzy control method comprises:

determining the membership degree of the overspeed percentage of the generator rotating speed of the wind generating set relative to a preset overspeed percentage fuzzy set;

determining the membership degree of the overspeed percentage change rate of the generator rotating speed of the wind generating set with respect to a preset overspeed percentage change rate fuzzy set;

and determining the additional pitch rate of the wind generating set by using a preset fuzzy control rule based on the membership degree of the overspeed percentage of the generator rotating speed of the wind generating set relative to the preset overspeed percentage fuzzy set and the membership degree of the overspeed percentage change rate of the generator rotating speed of the wind generating set relative to the preset overspeed percentage change rate fuzzy set.

4. The pitch control method of claim 3, wherein the step of determining a degree of membership of the overspeed percentage of the generator speed of the wind turbine generator set to a pre-set fuzzy set of overspeed percentages comprises:

and determining the membership of the overspeed percentage of the generator rotating speed of the wind generating set relative to a preset overspeed percentage fuzzy set based on the overspeed percentage of the generator rotating speed of the wind generating set and a preset overspeed percentage fuzzy set membership function.

5. The pitch control method of claim 3, wherein the step of determining a degree of membership of the overspeed percentage change rate of the generator speed of the wind turbine generator set to a preset fuzzy set of overspeed percentage change rates comprises:

and determining the membership of the overspeed percentage change rate of the generator rotating speed of the wind generating set relative to a preset overspeed percentage change rate fuzzy set based on the overspeed percentage change rate of the generator rotating speed of the wind generating set and a preset overspeed percentage change rate fuzzy set membership function.

6. The pitch control method of claim 3, wherein the step of determining the additional pitch rate of the wind park by using a preset fuzzy control rule comprises:

calculating the membership of the additional pitch rate to a preset additional pitch rate fuzzy set by using a preset fuzzy control rule based on the membership of the overspeed percentage of the generator rotating speed of the wind generating set to the preset overspeed percentage fuzzy set and the membership of the overspeed percentage change rate of the generator rotating speed of the wind generating set to the preset overspeed percentage change rate fuzzy set;

and calculating the additional pitch rate of the wind generating set based on the preset additional pitch rate fuzzy set and the membership of the additional pitch rate with respect to the preset additional pitch rate fuzzy set.

7. The pitch control method of claim 6, wherein the pre-set of additional pitch rate ambiguities comprises a plurality of additional pitch rate values.

8. The pitch control method of claim 7, wherein the step of calculating an additional pitch rate of the wind turbine includes: and calculating the additional pitch rate of the wind generating set by substituting the plurality of additional pitch rate values and the membership degree of the corresponding additional pitch rate with respect to the preset additional pitch rate fuzzy set into a preset additional pitch rate calculation formula.

9. The pitch control method of claim 4, wherein the preset overspeed percentage fuzzy set membership function comprises a normal function.

10. The pitch control method of claim 5, wherein the preset overspeed percentage change rate fuzzy set membership function comprises a normal function.

11. A pitch control device of a wind generating set, the pitch control device comprising:

the data acquisition unit is configured to acquire the overspeed percentage and the overspeed percentage change rate of the generator rotating speed of the wind generating set;

and the additional pitch rate determining unit is configured to determine the additional pitch rate of the wind generating set by using a fuzzy control method based on the obtained overspeed percentage and the overspeed percentage change rate of the generator rotating speed of the wind generating set.

12. A computer-readable storage medium having a computer program stored thereon, characterized in that the computer program, when being executed by a processor, carries out a pitch control method according to any one of claims 1 to 10.

13. A controller for a wind turbine generator set, the controller comprising:

a processor; and

a memory storing a computer program which, when executed by the processor, implements a pitch control method according to any of claims 1 to 10.

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