A wind turbine active power control method and device and storage medium

Abstract

The application discloses a wind turbine active power control method and device and a storage medium d The application discloses a wind turbine active power control method and device and a storage medium r The application discloses a wind turbine active power control method and device and a storage medium i The application discloses a wind turbine active power control method and device and a storage medium a The application discloses a wind turbine active power control method and device and a storage medium

Description

TECHNICAL FIELD

[0001] The present application relates to a wind turbine active power control method, device and storage medium, belonging to the technical field of wind turbine control. BACKGROUND

[0002] With the increasing penetration of wind power, wind turbines (referred to as wind turbines) operate in a maximum power point tracking (MPPT) mode with the goal of single-machine power generation efficiency. The output electromagnetic power fluctuates dramatically, which seriously affects the stability of the grid frequency. Therefore, wind turbines urgently need to have active power control (APC) function, so that the electromagnetic power can be output according to the grid power instruction to support the active balance of the grid.

[0003] Due to the change of wind turbine operation target, the adjustment of wind turbine electromechanical dynamics depends on the degree of pitch action. To solve this problem, the existing research adopts the technical route of using variable speed wind wheel to replace pitch, and proposes an APC method integrating rotor speed and pitch angle regulation (IAPC) based on variable speed and pitch coordination. The constant speed control is improved to speed interval control by using passive variable speed of arbitrary pitch angle wind wheel, which significantly reduces the pitch action of wind turbine. Through the coordination between speed regulation and pitch angle regulation, the utilization degree of passive variable speed of wind wheel is improved to reduce the frequency of pitch mechanism action. However, due to the improvement of this variable speed and pitch coordination mechanism, the influence of pitch control on the process of wind wheel variable speed has not been paid attention to. And in the existing research on pitch control, their focus is mainly on improving the power tracking or speed tracking performance (including accuracy and speed), and the influence of pitch control on the APC method mainly using wind wheel variable speed has not been discussed.

[0004] However, due to the speed limit of wind turbine pitch actuator, when the pitch angle instruction generated by the pitch controller changes beyond the speed limit, and the integral term in proportional-integral (PI) control is constantly accumulated, the pitch actuator cannot fully respond to the pitch angle instruction, and pitch rate saturation phenomenon occurs. This will cause excessive adjustment of wind turbine pitch angle, affect the subsequent passive variable speed process of wind wheel in the speed interval, and the wind wheel speed is easy to reach the speed boundary, and then the wind wheel overspeed and electromagnetic power drop phenomenon occurs. SUMMARY

[0005] The application aims to overcome the deficiencies in the prior art, and provide a wind turbine active power control method, device and storage medium, which improves the pitch controller by using compensation method, and gives the adaptive relationship between different saturation degrees and compensation coefficient k a based on the compensation type anti-saturation controller, reduces the influence of pitch rate saturation on the wind turbine variable speed process in the speed range, alleviates the wind turbine overspeed and electromagnetic power drop degree, and thus improves the wind turbine APC performance.

[0006] To achieve the above-mentioned purpose, the application is implemented by using the following technical scheme:

[0007] In a first aspect, the application provides a wind turbine active power control method, comprising:

[0008] obtaining the deviation Δβ between the pitch angle reference instruction β d and the actual value β r , determining whether the pitch controller enters the rate saturation state through Δβ, wherein the pitch controller comprises a main controller and a compensation controller;

[0009] when the pitch controller enters the rate saturation state, applying the anti-saturation compensation coefficient under different saturation degrees, which is calculated in advance by the fuzzy algorithm, to the integral coefficient k i of the main controller through the compensation controller, and realizing the wind turbine active power control considering the pitch execution saturation.

[0010] Further, the method of obtaining the deviation Δβ between the pitch angle reference instruction β d and the actual value β r , and determining whether the pitch controller enters the rate saturation state through Δβ, comprises:

[0011] obtaining the wind turbine related parameters, including the pitch angle reference instruction β d , the pitch angle actual value β r , the pitch angle reference instruction pitch rate dβ d / dt, and the pitch angle actual pitch rate dβ r / dt;

[0012] obtaining the response range of the pitch angle reference instruction pitch rate according to the pitch angle actual pitch rate;

[0013] comparing the pitch angle reference instruction pitch rate with the pitch angle actual pitch rate in one period to obtain the condition for the pitch controller to enter the rate saturation state;

[0014] obtaining the deviation Δβ between the pitch angle reference instruction β d and the actual value β rThe deviation Δβ between the pitch angle actual pitch rate and the pitch angle reference pitch rate is used to determine whether the pitch controller enters the rate saturation state.

[0015] Further, the response range of the pitch angle reference pitch rate obtained according to the pitch angle actual pitch rate includes:

[0016] The pitch angle actual pitch rate of the wind turbine in a unit time in the saturation state is calculated to obtain the rate limitation of the pitch actuator of the wind turbine, i.e., the maximum value |dβ r / dt| max ;

[0017] The pitch angle reference pitch rate dβ d / dt is limited in a certain response range:

[0018] |dβ d / dt|≤|dβ r / dt| max

[0019]

[0020] wherein dβ d / dt and dβ r / dt are the reference pitch rate and the pitch angle actual pitch rate, β d is the pitch angle reference, k p ·Δω(k) is a proportional term, is an integral term, k p and k i are proportional and integral coefficients, and ω is the wind rotor speed.

[0021] When the reference instruction issued by the pitch controller exceeds the rate limitation, the pitch angle actual value of the pitch actuator is:

[0022] β r (j)=β r (j-1)+(dβ r / dt) max ·Δt

[0023] wherein β r (j) is the pitch angle actual value at the current j time, and β r (j-1) is the pitch angle actual value at the previous time.

[0024] Further, the response range of the pitch angle reference pitch rate obtained according to the pitch angle actual pitch rate includes:

[0025] When |dβ d / dt|≤|dβr / dt| max time, β r (j) = β d (j), at this time the reference instruction issued by the pitch controller does not trigger the rate limit of the pitch actuator, and the integral term accumulates no amount, the actual action value of the pitch angle can respond to the reference instruction, and the PI control can achieve the expected effect;

[0026] When |dβ d / dt| > |dβ r / dt| max time, β r (j) = β r (j-1) + (dβ r / dt) max ·Δt, at this time the reference instruction has triggered the rate limit of the actuator, and the integral term accumulates an amount in the original change direction, so that the actual action value of the pitch angle cannot respond to the reference instruction, resulting in that the PI control cannot achieve the expected effect, and the pitch controller at this time is said to be in a rate saturation state.

[0027] Further, the method for determining whether the pitch controller enters the rate saturation state through Δβ includes:

[0028] When the pitch angle deviation Δβ is 0, the pitch controller does not enter the saturation state;

[0029] When the pitch angle deviation Δβ is not 0, the pitch controller enters the saturation state.

[0030] Further, when the pitch controller enters the rate saturation state, a certain compensation amount is applied to the integral coefficient k i of the main controller through the compensation controller, and the pitch angle reference instruction β d after compensation in the pitch controller is calculated as follows:

[0031]

[0032] The essence of the compensation method for resisting integral saturation is that when the controller enters the saturation state, a certain amount of compensation coefficient k i is applied to the integral coefficient k a of the main controller, so that the integral coefficient changes from k i to (k i -k a ·Δβ), that is, by reducing the integral coefficient this time, the continuous accumulation of the entire integral term is alleviated, and the wind turbine active power control considering the pitch execution saturation is realized.

[0033] Further, the anti-saturation compensation coefficient under different saturation degrees calculated by the fuzzy algorithm comprises:

[0034] The fuzzy controller takes error E and error change rate EC (dE / dt) as input, the input and output domain of the fuzzy controller are both [-6, 6], the fuzzy subset is {positive large, positive medium, positive small, zero, negative small, negative medium, negative large}, a triangular membership function is adopted, the fuzzy controller converts the input quantity Δω r into a corresponding fuzzy variable value to realize fuzzification, and further fuzzy reasoning is performed on the fuzzy input according to the formulated fuzzy rule, and the anti-saturation compensation coefficient k a is obtained after defuzzification; wherein the formulation method of the fuzzy controller rule is as follows:

[0035] When the error is positive large or positive medium, if the error change is positive, the error has a trend of increasing at this time, in order to eliminate the error as soon as possible, the control quantity needs to take the maximum value; if the error change is negative, the error has a trend of decreasing at this time, in order to reduce the error, the control quantity should take the minimum value;

[0036] When the error is positive, it indicates that the system is close to steady state, if the error change is positive, the output of the control quantity should take positive medium to suppress the error to develop in the positive direction; if the error change is negative, it indicates that the error is continuously reduced, at this time, the output of the control quantity should take positive small or zero;

[0037] When the error is negative large or negative medium, if the error change is negative, the error has a trend of increasing at this time, in order to eliminate the error as soon as possible, the control quantity needs to take the maximum value; if the error change is positive, the error has a trend of decreasing at this time, in order to reduce the error, the control quantity should take the minimum value;

[0038] When the error is negative, it indicates that the system is close to steady state, if the error change is negative, the output of the control quantity should take negative medium to suppress the error to develop in the negative direction; if the error change is positive, it indicates that the error is continuously reduced, at this time, the output of the control quantity should take negative small or zero;

[0039] When the error is zero, it indicates that the system is in steady state, at this time, the output of the control quantity should take or zero.

[0040] In a second aspect, the present application provides an active power control system of a wind turbine, comprising:

[0041] A judgment module is configured to obtain the deviation Δβ between the pitch angle reference instruction β d and the actual value β r , and determine whether the pitch controller enters the rate saturation state through Δβ, wherein the pitch controller comprises a main controller and a compensation controller;

[0042] A compensation module is configured to, when the pitch controller enters the rate saturation state, compensate the integral coefficient ki The anti-saturation compensation coefficient of different saturation degrees calculated by the fuzzy algorithm is applied to realize the wind turbine active power control considering the saturation of the variable pitch execution.

[0043] In a third aspect, the application provides an electronic device, comprising a processor and a storage medium;

[0044] The storage medium is used to store instructions;

[0045] The processor is used to operate according to the instructions to perform the steps of the method according to any one of the preceding aspects.

[0046] In a fourth aspect, the application provides a computer-readable storage medium, which stores a computer program, and the program is executed by a processor to realize the steps of the method according to any one of the preceding aspects.

[0047] Compared with the prior art, the application has the following beneficial effects:

[0048] (1) The application provides a wind turbine active power control method, device and storage medium, the variable pitch controller is improved by using the compensation method, and the adaptive relationship between different saturation degrees and compensation coefficients k a is given by combining the fuzzy algorithm, based on the compensation formula anti-saturation controller, the influence of the variable pitch rate saturation on the wind turbine variable speed process in the speed range is reduced, the wind turbine overspeed and the electromagnetic power drop degree are relieved, and the wind turbine APC performance is improved.

[0049] (2) Compared with the IAPC method, the wind turbine active power control method considering the saturation of the variable pitch execution reduces the influence of the variable pitch execution saturation on the wind turbine variable speed process. BRIEF DESCRIPTION OF DRAWINGS

[0050] Figure 1 is a flowchart of a wind turbine active power control method provided by an embodiment of the application;

[0051] Figure 2 is an IAPC control schematic diagram of a wind turbine based on passive variable speed of a wind turbine provided by an embodiment of the application;

[0052] Figure 3 is a rate saturation phenomenon schematic diagram provided by an embodiment of the application;

[0053] Figure 4 is a variable pitch execution mechanism schematic diagram with saturation effect provided by an embodiment of the application;

[0054] Figure 5 is a contrast schematic diagram of a pitch angle at a rated speed in a steady state and a saturation state provided by an embodiment of the application;

[0055] Figure 6is a compensation type anti-saturation variable pitch controller structure block diagram provided by the embodiment of the application;

[0056] Figure 7 is a trajectory diagram of the wind turbine under different APC methods in terms of electromagnetic power, rotor speed and pitch angle. DETAILED DESCRIPTION

[0057] The application will be further described below with reference to the drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the application, and cannot be used to limit the protection scope of the application.

[0058] Embodiment 1

[0059] The embodiment introduces a wind turbine active power control method, comprising:

[0060] obtaining the deviation Δβ between the pitch angle reference instruction β and the actual value β d , determining whether the pitch controller enters the rate saturation state through Δβ, wherein the pitch controller comprises a main controller and a compensation controller; r

[0061] When the pitch controller enters the rate saturation state, the compensation controller is used to apply the anti-saturation compensation coefficient at different saturation degrees, which is calculated through the fuzzy algorithm, to the integral coefficient k i of the main controller, so as to realize the wind turbine active power control considering the pitch execution saturation.

[0062] The wind turbine active power control method provided by the embodiment specifically involves the following steps in the application process:

[0063] Step 1, obtaining the wind turbine related parameters, including the rated speed ω N , the rotor speed ω, the pitch angle reference instruction β d , the actual pitch angle β r , the pitch angle reference instruction pitch rate dβ d / dt, the actual pitch angle pitch rate dβ r / dt;

[0064] Step 2, calculating the actual pitch angle change rate of the wind turbine in the rate saturation state;

[0065] Step 3, analyzing the relationship between the pitch angle reference instruction change rate and the actual pitch rate in a period;

[0066] Step 4, improving the pitch controller by using the compensation method, and giving the adaptive relationship between different saturation degrees and the compensation coefficient k a by combining the fuzzy algorithm;

[0067] ​Step 5, the wind active power control considering the saturation of the pitch execution is implemented based on a compensation type anti-windup controller.

[0068] Further, in one of the embodiments, the influence of the pitch saturation on the passive speed variation process of the wind wheel is analyzed based on the saturation phenomenon existing in the pitch mechanism, and the specific process includes:

[0069] The IAPC method based on passive speed variation adopts a proportional-integral element based pitch controller to implement the limit speed function. By separating the pitch angle up-regulation and down-regulation actions, the traditional constant speed control based on pitch regulation is changed to speed interval control, so that the wind wheel can operate at any pitch angle, thereby more effectively utilizing the kinetic energy of the wind wheel to buffer the short-term imbalance between aerodynamic power and electromagnetic power caused by wind speed fluctuations.

[0070] Passive speed variation is the main regulation means of the IAPC method, which has a significant influence on the APC performance of the wind turbine. However, the passive speed variation process is significantly affected by the size of the pitch angle in the speed interval. Therefore, during the operation of the wind turbine, the pitch rate saturation phenomenon causes the actual pitch action to be unable to fully respond to the reference command, affecting the pitch angle in the speed interval, and further affecting the speed variation process of the wind wheel and the APC performance.

[0071] Taking the pitch angle up-regulation process in the IAPC method as an example, when the pitch controller enters the saturation state, the integral term in the reference command calculation formula has a cumulative amount and cannot be abruptly changed, resulting in the pitch angle reference command being greater than the actual action value. When the speed reaches the rated speed and enters the interval, the pitch angle, which should have entered a constant state, remains in an increasing state due to the reference command, causing the actual value of the pitch angle to still increase. This causes the pitch angle in the speed interval to remain in an up-regulation state until it coincides with the constant reference command. Therefore, although the pitch execution mechanism has a mechanical rate limit, the up-regulation state of the pitch angle is prolonged, causing over-regulation of the pitch angle, resulting in the pitch angle entering the speed interval being too large.

[0072] The large pitch angle significantly affects the speed variation process of the wind wheel. After the speed of the wind wheel enters the speed interval, the wind turbine switches from pitch regulation to speed regulation to cope with subsequent weak gusts. The wind wheel enters the speed interval at a large pitch angle at the rated speed, reducing the wind energy capture capability of the wind wheel and exacerbating the speed drop process in the interval, making the speed more likely to reach the lower boundary of the speed interval.

[0073] In summary, under the influence of pitch rate saturation, the pitch angle is over-regulated, which further affects the passive speed variation process of the wind wheel and is not conducive to the active power control performance of the wind turbine.

[0074] Further, in one of the embodiments, the influence of the pitch saturation on the passive speed variation process of the wind wheel is analyzed based on the saturation phenomenon existing in the pitch mechanism, and the specific process includes: Figure 3Step 2, calculating the actual rate of change of the pitch angle of the wind turbine under rate saturation, specifically includes the following process:

[0075] By calculating the change dβ of the actual value of the blade pitch angle of the wind turbine per unit time under saturation conditions. r / dt indicates that the pitch actuator of the wind turbine has a rate limit, that is, the actual pitch rate has a maximum value |dβ. r / dt| max Therefore, the rate of change of the pitch angle reference command dβ d / dt will be limited to a certain response range:

[0076] |dβ d / dt|≤|dβ r / dt| max

[0077]

[0078] Where, dβ d / dt and dβ r / dt represents the reference command pitch rate and the actual pitch rate at the pitch angle, β d For pitch angle reference command, k p ·Δω(k) is the proportional term, For the integral term, k p With k i These are the proportional coefficient and the integral coefficient, respectively.

[0079] When the reference command issued by the pitch controller exceeds the rate limit, the actual pitch angle of the pitch actuator is:

[0080] β r (j)=β r (j-1)+(dβ r / dt) max ·Δt

[0081] Where, β r (j) represents the actual pitch angle at the current time (time j), β r (j-1) represents the actual pitch angle value at the previous moment.

[0082] Furthermore, in one embodiment, combined with Figure 4 Step 3 analyzes the relationship between the rate of change of the reference pitch angle command and the actual pitch rate within one cycle, specifically including:

[0083] By analyzing the rate of change of the pitch angle reference command |dβ within one cycle d / dt| and the maximum actual pitch rate|dβ r / dt| maxThe relationship between them can be divided into the following two situations:

[0084] When |dβ d / dt|≤|dβ r / dt| max When, then β r (j)=β d (j), at this time the reference command issued by the pitch controller is not...

[0085] The rate limit of the pitch actuator is triggered, and the integral term... There is no accumulated value. The actual pitch angle action value can respond to the reference command, and the PI control can achieve the expected effect;

[0086] When |dβ d / dt|>|dβ r / dt| max When, then β r (j)=β r (j-1)+(dβ r / dt) max ·Δt, at which point the reference instruction has triggered the rate limit of the actuator, and the integral term The accumulation of a certain amount in the original direction of change causes the actual pitch angle action value to fail to respond to the reference command, which is equivalent to a saturation element connected in series in the pitch actuator, resulting in the PI control failing to achieve the expected effect.

[0087] In summary, when the rate of change of the pitch angle reference command is |dβ d / dt|exceeds the actuator's rate limit|dβ r / dt| max And the integral term If an accumulation occurs in the original direction, the pitch controller is said to be in a rate saturation state.

[0088] Further, in step 4, combining Figure 4 , Figure 5 and Figure 6 An improvement to the pitch controller is achieved using a compensation method, and fuzzy algorithms are used to determine the relationship between different saturation levels and the compensation coefficient k. a The compatibility relationships between them specifically include:

[0089] Step 4-1 involves designing an anti-saturation pitch controller using the compensation method, which is divided into two parts:

[0090] (1) The main controller is the original PI control structure. It can realize the basic speed limiting function in the IAPC strategy as well as the speed regulation function at any pitch angle.

[0091] (2) Compensation controller, used to realize the anti-saturation operation of the controller. The input of the compensation controller is the deviation Δβ between the pitch angle reference command β d and the actual value β r . Whether the controller is in a saturation state is determined by judging whether Δβ is 0, and then the compensation coefficient k a is amplified and fed back to the integral term of the PI link to alleviate the accumulation of the integral term by reducing the integral coefficient of this time, thereby realizing anti-saturation. The compensation coefficient is determined by the speed information obtained through fuzzy algorithm, so as to cope with different saturation degrees under different wind conditions.

[0092] When the pitch angle deviation Δβ is 0, the pitch controller does not enter the saturation state, and only the main controller based on the PI link plays a role. At this time, the pitch angle reference command can be fully responded, and the compensation controller does not work. When the pitch angle deviation Δβ is not 0, the pitch controller appears saturation phenomenon, at this time, the reference command cannot be fully responded by the actual value, the compensation controller gives a certain compensation amount to the integral coefficient, and realizes the anti-saturation function by reducing the accumulation of the integral term. The pitch angle reference command β d in the controller after compensation is calculated as follows:

[0093]

[0094] The essence of the compensation method for anti-integral saturation is that when the controller enters the saturation state, a certain compensation amount is applied to the integral coefficient k i of the main controller, so that the integral coefficient changes from k i to (k i -k a ·Δβ), that is, the integral coefficient of this time is reduced to alleviate the continuous accumulation of the integral term, thereby realizing the wind turbine active power control considering the saturation of the pitch execution. The size of the compensation amount is related to β d , β r and the compensation coefficient k a .

[0095] Step 4-2, the adaptive relationship between different saturation degrees and the compensation coefficient k a is given by combining the fuzzy algorithm, which is specifically:

[0096] When the speed of the wind turbine exceeds the limit under the IAPC strategy, the pitch angle is adjusted to make the rotor speed run within the speed range, but the saturation of the pitch rate will affect the speed process of the rotor, and then affect the performance of the wind turbine active power control. In fact, the saturation degree of the wind turbine pitch is different under different wind conditions. In order to avoid the situation of insufficient compensation or excessive compensation, the compensation controller needs to apply the corresponding anti-saturation compensation coefficient according to different saturation degrees.

[0097] Considering that the fuzzy control has the characteristics of nonlinearity, strong robustness, strong adaptability to wind speed changes and the ability to cope with random and fluctuating turbulent wind conditions, the fuzzy control algorithm is selected for the compensation controller of the wind turbine to output corresponding anti-saturation compensation coefficients under different wind conditions.

[0098] The fuzzy controller takes error E and error change rate EC (dE / dt) as the input of the controller. The input and output domains of the fuzzy control are both [-6, 6], and the fuzzy subsets are {positive large, positive medium, positive small, zero, negative small, negative medium, negative large}, all of which adopt a triangular membership function. The fuzzy controller converts the input quantity Δω r into a corresponding fuzzy variable value to realize fuzzification, and further fuzzy reasoning is performed on the fuzzy input according to the formulated fuzzy rules, and the anti-saturation compensation coefficient k a is obtained after defuzzification. The formulation method of the fuzzy controller rules is as follows:

[0099] 1) When the error is positive large or positive medium, if the error changes positively, the error has a tendency to increase at this time, and in order to eliminate the error as soon as possible, the control quantity needs to take the maximum value; if the error changes negatively, the error has a tendency to decrease at this time, and in order to reduce the error, the control quantity should take the minimum value.

[0100] 2) When the error is positive, it means that the system is close to steady state, if the error changes positively, the output of the control quantity should be positive medium to suppress the error to develop in the positive direction; if the error changes negatively, it means that the error is continuously reduced, at this time the output of the control quantity should be positive small or zero.

[0101] 3) When the error is negative large or negative medium, if the error changes negatively, the error has a tendency to increase at this time, and in order to eliminate the error as soon as possible, the control quantity needs to take the maximum value; if the error changes positively, the error has a tendency to decrease at this time, and in order to reduce the error, the control quantity should take the minimum value.

[0102] 4) When the error is negative, it means that the system is close to steady state, if the error changes negatively, the output of the control quantity should be negative medium to suppress the error to develop in the negative direction; if the error changes positively, it means that the error is continuously reduced, at this time the output of the control quantity should be negative small or zero.

[0103] 5) When the error is zero, it means that the system is in steady state, at this time the output of the control quantity should be zero.

[0104] Further, step 5, based on the compensation type anti-saturation controller, the wind turbine active power control considering variable pitch execution saturation is realized, specifically including:

[0105] Based on the adaptive relationship given by the fuzzy algorithm, the corresponding compensation coefficient is output under different saturation degrees, fed back to the integral term, and the continuous accumulation of the entire integral term is relieved by reducing the integral coefficient of this time, thereby realizing the wind turbine active power control considering the pitch execution saturation.

[0106] Embodiment 2

[0107] The embodiment provides a wind turbine active power control system, comprising:

[0108] A judgment module is configured to obtain the deviation Δβ between the pitch angle reference instruction β d and the actual value β r , and determine whether the pitch controller enters the rate saturation state through the deviation Δβ, wherein the pitch controller comprises a main controller and a compensation controller.

[0109] A compensation module is configured to, when the pitch controller enters the rate saturation state, apply the anti-saturation compensation coefficient of different saturation degrees calculated in advance through the fuzzy algorithm to the integral coefficient k i of the main controller through the compensation controller, so as to realize the wind turbine active power control considering the pitch execution saturation.

[0110] For specific limitations of the wind turbine active power control system, refer to the limitations of the wind turbine active power control method in embodiment 1, which will not be repeated here. Each module in the above wind turbine active power control system can be realized by software, hardware and combinations thereof, in whole or in part. The above modules can be embedded in or independent of the processor in the computer device in hardware form, or can be stored in the memory in the computer device in software form, so as to be called and executed by the processor to perform the operations corresponding to each module.

[0111] Embodiment 3

[0112] The embodiment provides an electronic device, comprising a processor and a storage medium.

[0113] The storage medium is configured to store instructions.

[0114] The processor is configured to operate according to the instructions to perform the steps of the method according to any one of embodiments 1.

[0115] Embodiment 4

[0116] The embodiment provides a computer-readable storage medium having a computer program stored thereon, which is executed by a processor to implement the steps of the method according to any one of embodiments 1.

[0117] Embodiment 5

[0118] As a specific example, in one of the embodiments, the present application is further verified and described.

[0119] This embodiment uses the open-source professional wind turbine simulation software FAST (Fatigue, Aerodynamics, Structures, and Turbulence) provided by the National Renewable Energy Laboratory (NREL) to simulate and verify the effect. The wind turbine model uses a CART3 blade test machine with a capacity of 350kW, and the specific parameters are shown in Table 1.

[0120] Table 1 Main parameters of CART 3 blade test machine with a capacity of 350kW

[0121]

[0122] The wind turbine active power control method considering the saturation of the pitch execution of the present application includes the following contents:

[0123] 1. Obtain the relevant coefficients of the wind turbine, including the rated speed ω N , the rotor speed ω, the pitch angle reference command β d , the actual value of the pitch angle β r , the pitch angle reference command pitch rate dβ d / dt, the actual pitch angle pitch rate dβ r / dt;

[0124] 2. Calculate the actual change rate of the pitch angle of the wind turbine in the rate saturation state, specifically including:

[0125] By calculating the change amount dβ r / dt of the actual value of the pitch angle of the wind turbine in unit time in the saturation state, it can be concluded that the pitch execution mechanism of the wind turbine exists rate limit, that is, the actual pitch rate of the pitch angle exists maximum value |dβ r / dt| max Therefore, the change rate dβ d / dt of the pitch angle reference command will be limited within a certain response range:

[0126] |dβ d / dt|≤|dβ r / dt| max

[0127]

[0128] Wherein, dβ d / dt and dβ r / dt are the reference command pitch rate and the actual pitch rate of the pitch angle, β d is the pitch angle reference command, k p·Δω(k) is the proportional term, For the integral term, k p With k i These are the proportional coefficient and the integral coefficient, respectively.

[0129] When the reference command issued by the pitch controller exceeds the rate limit, the actual pitch angle of the pitch actuator is:

[0130] β r (j)=β r (j-1)+(dβ r / dt) max ·Δt

[0131] Where, β r (j) represents the actual pitch angle at the current time (time j), β r (j-1) represents the actual pitch angle value at the previous moment.

[0132] 3. Analyze the relationship between the rate of change of the reference pitch angle command and the actual pitch rate within one cycle, specifically including:

[0133] By analyzing the rate of change of the pitch angle reference command |dβ within one cycle d / dt| and the maximum actual pitch rate|dβ r / dt| max The relationship between them can be divided into the following two situations:

[0134] When |dβ d / dt|≤|dβ r / dt| / max When, then β r (j)=β d (j) At this point, the reference command issued by the pitch controller does not trigger the rate limit of the pitch actuator, and the integral term... There is no accumulated value. The actual pitch angle action value can respond to the reference command, and the PI control can achieve the expected effect;

[0135] When |dβ d / dt|>|dβ r / dt| max When, then β r (j)=β r (j-1)+(dβ r / dt) max ·Δt, at which point the reference instruction has triggered the rate limit of the actuator, and the integral term The accumulation of a certain amount in the original direction of change causes the actual pitch angle action value to fail to respond to the reference command, which is equivalent to a saturation element connected in series in the pitch actuator, resulting in the PI control failing to achieve the expected effect.

[0136] In summary, when the rate of change of the pitch angle reference command |dβ d / dt| exceeds the rate limit of the actuator |dβ r / dt| max , and the integral term The cumulative amount appears in the original direction, and at this time the pitch controller is in the rate saturation state.

[0137] 4. The pitch controller is improved by using compensation method, and the adaptive relationship between different saturation degrees and compensation coefficient k a is given by combining fuzzy algorithm, specifically including:

[0138] Because the saturation degree of the wind turbine pitch is different under different wind conditions, in order to avoid the situation of insufficient compensation or excessive compensation, the corresponding anti-saturation compensation coefficient needs to be applied according to different saturation degrees. According to the characteristics of fuzzy control, such as nonlinearity and strong robustness, the fuzzy control algorithm is selected for the anti-saturation controller of the wind turbine, so as to output the corresponding compensation coefficient under different wind conditions.

[0139] 5. The wind turbine active power control considering the pitch execution saturation is realized based on the compensation type anti-saturation controller, specifically including:

[0140] Based on the adaptive relationship given by the fuzzy algorithm, the corresponding compensation coefficient is output under different saturation degrees, and is fed back to the integral term. By reducing the integral coefficient this time, the continuous accumulation of the entire integral term is relieved, and then the wind turbine active power control considering the pitch execution saturation is realized.

[0141] 6. Under the same simulation wind speed (300s turbulent wind speed sequence, average wind speed is 10m / s, and turbulent intensity is A level) and power instruction (the power instruction is set to 350kW) scene setting, the IAPC method and the improved method proposed in the application are simulated, and the control performance indexes of the wind turbine under the two methods are shown in Table 2. The speed, pitch angle and electromagnetic power trajectory of the wind turbine under different methods are shown in Figure 7 .

[0142] Table 2 Comparison of control effect indexes

[0143]

[0144] Through the analysis of the above control effect indexes, it can be seen that by improving the pitch controller by compensation type anti-saturation, and using fuzzy algorithm to determine the anti-saturation compensation coefficient according to the running state of the wind turbine, the influence of rate saturation on pitch control is reduced, and the wind turbine is improved in three aspects of wind speed regulation, pitch mechanism load and power instruction response performance.

[0145] The simulation experiment results show that the wind turbine active power control method considering the variable pitch execution saturation can reduce the influence of variable pitch saturation on the variable speed process of the wind wheel, relieve the overspeed of the wind wheel and the degree of electromagnetic power drop, and thus improve the APC performance of the wind turbine.

[0146] The above only describes the preferred embodiments of the present application, and it should be noted that those skilled in the art can make several improvements and modifications without departing from the technical principles of the present application, and these improvements and modifications should also be considered as the protection scope of the present application.

Claims

1. A method of active power control for a wind turbine generator, characterized by, The method comprises the following steps: Obtaining wind turbine related parameters, including pitch angle reference command , pitch angle actual value , pitch angle reference command pitch rate , pitch angle actual pitch rate ; According to the actual pitch angle changing rate, the response range of the pitch angle reference instruction changing rate is obtained; The pitch angle reference instruction changing rate in a period is compared with the actual pitch angle changing rate to obtain the condition for the pitch control entering the rate saturation state; Based on the conditions under which the pitch controller enters rate saturation, obtain the pitch angle reference command. Compared with actual value Deviation between ,pass Determine whether the pitch controller has entered a rate saturation state. The pitch controller includes a main controller and a compensation controller. When the pitch controller enters the rate saturation state, the integral coefficient of the main controller is compensated by the compensation controller The anti-saturation compensation coefficients of different saturation degrees calculated in advance by the fuzzy algorithm are applied to realize the wind turbine active power control considering the pitch execution saturation. The anti-saturation compensation coefficients in different saturation degrees obtained by the fuzzy algorithm comprise: The fuzzy controller takes the error and the error change rate as inputs, and the input and output domains of the fuzzy controller are , and the fuzzy subsets are The fuzzy controller converts the input quantities into corresponding fuzzy variable values to realize fuzzification, and further performs fuzzy reasoning on the fuzzy inputs according to the formulated fuzzy rules to obtain the anti-saturation compensation coefficient after defuzzification; wherein the method for formulating the fuzzy controller rules is as follows: When the error is positive large or positive medium, if the error changes positively, the error has a tendency to increase at this time, in order to eliminate the error as soon as possible, the control quantity needs to take the maximum value; if the error changes negatively, the error has a tendency to decrease at this time, in order to reduce the error, the control quantity should take the minimum value; When the error is positive, it indicates that the system is close to steady state, if the error changes positively, the output of the control quantity should take positive medium to suppress the error to develop in the positive direction; if the error changes negatively, it indicates that the error is continuously reduced, at this time, the output of the control quantity should take positive small or zero; When the error is negative large or negative medium, if the error changes negatively, the error has a tendency to increase at this time, in order to eliminate the error as soon as possible, the control quantity needs to take the maximum value; if the error changes positively, the error has a tendency to decrease at this time, in order to reduce the error, the control quantity should take the minimum value; When the error is negative, it indicates that the system is close to steady state, if the error changes negatively, the output of the control quantity should take negative medium to suppress the error to develop in the negative direction; if the error changes positively, it indicates that the error is continuously reduced, at this time, the output of the control quantity should take negative small or zero; When the error is zero, it indicates that the system is in steady state, at this time, the output of the control quantity should take or zero.

2. The wind turbine active power control method of claim 1, wherein, The response range of the pitch angle reference instruction changing rate obtained according to the actual pitch angle changing rate comprises: By calculating the change of the actual value of the pitch angle of the fan in a unit of time in the saturated state, it is obtained that the pitch execution mechanism of the fan has a speed limit, that is, the actual pitch speed of the pitch angle has a maximum value ; Pitch angle reference command pitch rate be limited to a certain response range: ； ； wherein and is a reference pitch rate and a pitch angle actual pitch rate, is a pitch angle reference, is a proportional term, is an integral term, and are a proportional coefficient and an integral coefficient, respectively, is a wind rotor speed; When the reference instruction issued by the pitch control exceeds the rate limit, the actual pitch angle value of the pitch actuator is: ； wherein is the current instantaneous pitch angle actual value, is the previous instantaneous pitch angle actual value.

3. The wind turbine active power control method of claim 2, wherein, The condition for the pitch control entering the rate saturation state obtained by comparing the pitch angle reference instruction changing rate in a period with the actual pitch angle changing rate comprises: When , the reference instruction issued by the pitch controller does not trigger the rate limit of the pitch actuator, and the integral term does not accumulate an amount, and the actual action value of the pitch angle can respond to the reference instruction, and the PI control can achieve the expected effect. ​ When then At this time, the reference instruction has triggered the rate limit of the actuator, and the integral term The cumulative amount appears in the original change direction, so that the actual action value of the pitch angle cannot respond to the reference instruction, resulting in that the PI control cannot achieve the expected effect, and at this time the pitch controller is in the rate saturation state.

4. The wind turbine active power control method of claim 1, wherein, The passage Determining whether the pitch controller enters a rate saturation state comprises: When the pitch angle deviation is 0, the pitch controller is not in saturation. When the pitch angle deviation If the pitch angle deviation is not 0, the pitch controller enters a saturated state.

5. The wind turbine active power control method of claim 2, wherein, When the pitch controller enters the rate saturation state, the integral coefficient of the main controller is compensated by the compensation controller A certain compensation amount is applied to the pitch angle reference command in the pitch controller after compensation The calculation formula is: ； Wherein, the essence of the compensation method to resist integral saturation is that when the controller enters the saturation state, the integral coefficient of the main controller is reduced A certain amount of compensation coefficient is applied So that the integral coefficient is changed from To That is, by reducing the integral coefficient this time, the continued accumulation of the entire integral term is alleviated, and the wind turbine active power control considering the saturation of the variable pitch execution is realized.

6. A wind turbine active power control system for implementing the wind turbine active power control method of claim 1, characterized by, The method comprises the following steps: a judging module configured to acquire a pitch angle reference instruction deviation between the actual value and the reference value , by judging whether a pitch controller enters a rate saturation state, wherein the pitch controller comprises a main controller and a compensation controller; The compensation module is configured to compensate the integral coefficient of the main controller by the compensation controller when the pitch controller enters the rate saturation state The anti-saturation compensation coefficients under different saturation degrees calculated by the fuzzy algorithm in advance are applied to realize the wind turbine active power control considering the pitch execution saturation.

7. An electronic device, comprising: The storage medium is used for storing instructions; The processor is used for operating according to the instructions to perform the steps of the method according to any one of claims 1-5. The program is executed by the processor to realize the steps of the method according to any one of claims 1-5.

8. A computer readable storage medium having stored thereon a computer program, characterized in that: ​

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