Blade clearance control method and system based on blade posture judgment

Abstract

The application discloses a kind of based on blade posture judgment's blade clearance control method and system, the method includes the following steps: including the following steps: S1, the blade movement information of wind turbine is collected;S2, blade movement posture is solved;S3, establish coordinate system and safety range threshold value;S4, draw blade movement trajectory;S5, monitor blade position, obtain safety monitoring result;S6, return safety monitoring result to wind turbine, guide wind turbine variable pitch, complete clearance control;Data involved in the application in clearance detection is related to blade itself rather than external data, with minimal degree of interference from environment, weather and other external factors, with universality;It can also assist in detecting blade damage, blade rotation imbalance and abnormal pitch system while simultaneously achieving comprehensive real-time detection of blade operation.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of wind turbine blade clearance control, in particular to a blade clearance control method and system based on blade posture judgment. BACKGROUND

[0002] In recent years, with the improvement of China's wind power research and development capability, the single machine capacity of wind turbine is continuously improved, and the wind turbine gradually tends to be large-scale. As the core component of capturing wind energy, the blade also becomes larger and lighter, and more flexible, which increases the safety hazard of wind turbine blade sweeping the tower. The current common blade clearance safety monitoring methods are as follows:

[0003] (1) Radar scanning scheme: using different types of radar to detect the blade clearance distance when the blade sweeps the tower area during the operation of the wind turbine;

[0004] (2) Video monitoring and monitoring scheme: using special cameras installed in a specific direction, combined with video frame extraction technology and edge detection technology in image processing, to calculate the blade clearance distance when the blade sweeps the tower area;

[0005] The common blade clearance safety monitoring methods have certain unstable factors: in the radar scanning scheme, the electromagnetic wave used for ranging is greatly affected by interference, such as the refraction effect of water droplets on electromagnetic waves in rainy days, which greatly reduces the ranging effect; in the video monitoring and monitoring scheme, due to the influence of the camera installation position, after the unit yaw, it will have a great influence on the image processing result. SUMMARY

[0006] The purpose of the present application is to overcome the shortcomings of the prior art, and to provide a blade clearance control method and system based on blade posture judgment. The sensor is used to capture the real-time running track of the blade, which can detect the blade clearance and also assist in monitoring the health of the blade.

[0007] The purpose of the present application is achieved by the following technical scheme: a blade clearance control method based on blade posture judgment, comprising the following steps:

[0008] S1, collecting blade movement information of a wind turbine;

[0009] S2, solving the blade movement posture according to the collected blade movement information;

[0010] S3, establishing a coordinate system and a safety range threshold value through the blade movement posture and the blade movement information;

[0011] S4, drawing a blade motion trajectory according to the blade motion information and the coordinate system;

[0012] S5, monitoring a blade position according to the blade motion trajectory to obtain a safety monitoring result;

[0013] S6, returning the safety monitoring result to the wind turbine, and if the blade position exceeds a safety range, sending a clearance safety risk warning to a control module of the wind turbine to guide the wind turbine to pitch and complete clearance control.

[0014] Further, the step S1 comprises the following steps:

[0015] A sensor is installed at a preset position of a blade of the wind turbine, and current blade motion information is measured, including three-axis acceleration, three-axis angular velocity, altitude and Beidou geographic information.

[0016] Further, the step S2 comprises the following steps:

[0017] Signals of the current blade motion information are collected, white noise is suppressed, Kalman filtering is performed on the signals, and a motion solving equation is used to solve the attitude of the current blade motion.

[0018] The motion solving process presents the attitude of the object in the form of a quaternion, and the formula is as follows:

[0019] q = [q0, q1, q2, q3];

[0020] wherein q0 is a scalar, which is 1 in the initial state, representing the cosine of half of the included angle θ between the current state and the standard state, and q1, q2 and q3 are vector coefficients, mainly representing the rotation change of the object in three-dimensional space, which are 0 in the initial state.

[0021] When the object moves, its attitude is considered to be a three-axis rotation process based on the original quaternion, so the angular velocity values of the three-axis motion of the object in the space are obtained, denoted as ω bx , ω by and ω bz , and according to the quaternion differential relationship between the angular velocity and the quaternion in the inertial motion system:

[0022]

[0023] wherein

[0024]

[0025] wherein

[0026]

[0027] The rotation of the quaternion is completed, and the current object relative to the pitch angle, roll angle, and yaw angle changes in the static state are obtained through the calculation, and the components of the gravitational acceleration are constructed to eliminate the influence of the gravitational acceleration in the integral calculation.

[0028] Further, the step S3 comprises the following steps:

[0029] A coordinate system is created in three-dimensional space, and relative coordinate points in space are drawn by importing the relative positions between multiple sensors. At the same time, the current yaw angle data of the wind turbine generator set and the design clearance distance parameter of the set are used to estimate the current position of the sensor relative to the tower, obtain the path estimation of the sensor during the yawing process of the set, and simulate the coordinate points to confirm the initial position of the blade sensor before the wind turbine generator set is started after installation, construct the blade static position, and confirm the position of the safe range. According to the path estimation result and the set clearance design distance setting, the distance is set to be 0.4*set clearance design distance minus the estimated motion path inward.

[0030] Further, the step S4 comprises the following steps:

[0031] During the continuous operation of the wind turbine generator set, the blade attitude is continuously calculated and the motion distance is calculated according to the sensor motion information. The motion distance needs to process the accelerometer data as follows:

[0032] S41, the accelerometer measurement result is eliminated by analyzing the calculated object attitude and eliminating the gravitational acceleration;

[0033] S42, the influence of external factors on the accelerometer due to blade vibration is eliminated by high-pass filtering;

[0034] S43, the second median integral is performed on the acceleration of each axis, the first median integral obtains the linear velocity, the accelerometer is calibrated by the impeller rotating speed, and the second median integral obtains the motion distance;

[0035] The complete motion trajectory data of the blade during the operation of the wind turbine generator set is drawn in the algorithm coordinate system.

[0036] Further, the step S5 comprises the following steps:

[0037] In the three-dimensional space of the algorithm, whether the blade position gradually approaches the safe range surface or has cut into the safe range surface during the operation of the wind turbine generator set is calculated according to the blade motion trajectory, and the safety monitoring result is obtained.

[0038] Further, the step S6 comprises the following steps:

[0039] According to the safety monitoring result, the monitoring result is sent to the wind turbine, if the moving distance is within the safety range, no need to change the pitch, normal operation according to the control instruction, if the moving distance exceeds the safety range, the clearance safety risk warning is sent to the wind turbine control module, guiding the wind turbine to change the pitch action, completing the clearance control process.

[0040] A blade clearance control system based on blade posture judgment is used to realize the blade clearance control method based on blade posture judgment.

[0041] The acquisition module is used to acquire the blade motion information of the wind turbine.

[0042] The blade motion posture solving module is used to solve the blade motion posture according to the acquired blade motion information.

[0043] The coordinate system and safety range threshold establishing module is used to establish the coordinate system and safety range threshold through the blade motion posture and the blade motion information.

[0044] The blade motion trajectory drawing module is used to draw the blade motion trajectory according to the blade motion information and the coordinate system.

[0045] The safety monitoring module is used to monitor the blade position according to the blade motion trajectory.

[0046] The clearance control module is used to send the clearance safety risk warning to the wind turbine control module according to the monitored blade position, guide the wind turbine to change the pitch, and complete the clearance control.

[0047] A non-transitory computer readable medium storing instructions, when executed by a processor, performs the steps of the blade clearance control method based on blade posture judgment.

[0048] A computing device includes a processor and a memory for storing processor executable programs, when the processor executes the programs stored in the memory, the blade clearance control method based on blade posture judgment is realized.

[0049] Compared with the prior art, the present application has the following advantages and beneficial effects:

[0050] 1、The data participating in the clearance detection in the present application is related to the blade itself rather than external data, and is extremely small in the degree of interference from external factors such as environment and weather, and has universality.

[0051] 2、In addition to detecting the clearance distance, the present application can also realize comprehensive and real-time detection of the blade running process, so it can also assist in detecting blade damage, blade rotation imbalance and abnormal pitch system. BRIEF DESCRIPTION OF DRAWINGS

[0052] Figure 1 Figure 1 is a schematic diagram of a sensor installation position based on a blade face attitude.

[0053] Figure 2 Figure 2 is a schematic diagram of a sensor installation position based on a blade face attitude. Figure 1 Figure 3 is a schematic diagram of a wind turbine operating process blade trajectory scanning line based on a sensor installation position.

[0054] Figure 3 Figure 4 is a schematic diagram of a sensor installation position based on a blade bending degree.

[0055] Figure 4 Figure 5 is a schematic diagram of a wind turbine operating process blade trajectory scanning line based on a sensor installation position. Figure 3 DETAILED DESCRIPTION

[0056] The present application will be further described below in conjunction with specific embodiments.

[0057] Embodiment 1

[0058] Referring to Figure 1, the present embodiment provides a blade clearance control method based on blade attitude determination, including the following steps: Figures 1 to 2 S1, collecting blade movement information of a wind turbine, including the following steps:

[0059] A sensor is installed at a position where the blade of the wind turbine is significantly deformed, and each blade is provided with one sensor, as shown in Figure 1, three sensors A, B and C measure the current blade movement information, and the blade movement information includes three-axis acceleration, three-axis angular velocity, altitude and Beidou geographic information.

[0060] Figure 1 S2, solving the blade movement attitude according to the collected blade movement information, including the following steps:

[0061] Through the collected current blade movement information signal, the signal is returned to the computing module of the wind turbine through optical fiber or wireless, the signal is processed by white noise suppression and Kalman filtering, and the current blade movement attitude is solved through a movement solving equation.

[0062] The movement solving process presents the attitude of the object in the form of a quaternion, and its formula is as follows:

[0063] q = [q0, q1, q2, q3];

[0064] where q0 is a scalar, which is 1 in the initial state, representing the cosine of half the angle θ between the current state and the standard state, q1, q2 and q3 are vector coefficients, mainly representing the rotation change of the object in three-dimensional space, which are 0 in the initial state.

[0065]

[0066] ​​​When the object generates motion, its attitude is considered to be a three-axis rotation process based on the original quaternion, so the angular velocity values of the three-axis motion of the object relative to the space are obtained, denoted as ω bx by bz According to the quaternion differential relationship between the angular velocity and the quaternion in the inertial motion system:

[0067]

[0068] In the formula

[0069]

[0070] Among them

[0071]

[0072] The rotation of the quaternion is completed, and through the calculation, the change of the pitch angle, the roll angle and the yaw angle of the current object relative to the static state can be obtained, and then the components of the gravitational acceleration are constructed to eliminate the influence of the gravitational acceleration in the integral calculation.

[0073] S3, a coordinate system and a safety range threshold are established through the blade motion attitude and the blade motion information, including the following steps:

[0074] A coordinate system is created in a three-dimensional space, relative coordinate points in the space are drawn by importing the relative positions between multiple sensors, and the current yaw angle data of the wind turbine generator and the design clearance distance parameters of the unit are used to estimate the current position of the sensor relative to the tower drum, to obtain the path estimation of the sensor during the yawing process of the unit, and to simulate the coordinate points based thereon to confirm the initial position of the blade sensor before the wind turbine generator is started after installation, to construct the blade static position, and to confirm the position of the safety range. According to the path estimation result and the unit clearance design distance setting, the distance is estimated to be 0.4*unit clearance design distance inward, and the blade static position and the safety range position are both three-dimensional curved surfaces around the tower drum, considering the influence of yaw and nacelle pitch angle.

[0075] S4, a blade motion trajectory is drawn according to the blade motion information and the coordinate system, including the following steps:

[0076] During the continuous operation of the wind turbine generator, the blade attitude is continuously calculated according to the sensor motion information, and the acceleration change interference caused by the variable speed circular motion of the blade and the gravity is removed, and the motion distance needs to be processed as follows:

[0077] S41, the accelerometer measurement results are gravity acceleration eliminated by analyzing the calculated object attitude; ​​

[0078] S42, eliminate the influence of external factors on the accelerometer by high-pass filtering;

[0079] S43, secondary median integration is performed on the acceleration of each axis, the first median integration obtains the linear velocity, and the accelerometer is calibrated by using the rotating speed of the impeller, and the second median integration obtains the movement distance;

[0080] In the three-dimensional space coordinate system of the algorithm, the complete motion trajectory data of the blade during the operation of the wind turbine generator set is drawn, and the motion trajectory of the blade is a trajectory circle, as shown in Figure 2 , wherein D3 is a safety range line, D2 is a static initial line, and D1 is a trajectory circle.

[0081] S5, according to the blade motion trajectory, the blade position is monitored to obtain a safety monitoring result, including the following steps:

[0082] In the three-dimensional space of the algorithm, according to the blade motion trajectory, it is determined whether the blade position gradually approaches the safety range surface or has cut into the safety range surface during the operation of the wind turbine generator set, to obtain a safety monitoring result.

[0083] S6, return the safety monitoring result to the wind turbine generator set, if the blade position exceeds the safety range in the safety monitoring result, send a clearance safety risk warning to the wind turbine generator control module to guide the wind turbine generator to pitch, complete the clearance control, including the following steps:

[0084] According to the safety monitoring result, the monitoring result is sent to the wind turbine generator, if the movement distance is within the safety range, no pitching is required, and the wind turbine generator operates normally according to the control instruction, if the movement distance exceeds the safety range, a clearance safety risk warning is sent to the wind turbine generator control module to guide the wind turbine generator to pitch, and the clearance control process is completed.

[0085] Embodiment 2

[0086] As shown in Figures 3 to 4 , the difference between this embodiment and embodiment 1 is that in step S1, a plurality of sensors are installed at the blade flexible deformation significant position and the blade root of the wind turbine generator, as shown in Figure 3 , three sensors A1, A2, A3, B1, B2, B3, C1, C2, C3 are arranged on each blade, and the blade motion trajectory generated by the sensors is an arc along the surface of the blade; in step S3, since the tracked trajectory shape in this embodiment is only a curve, it is not necessary to build a space coordinate system, and it can be reduced to a two-dimensional plane coordinate system, and the main judgment index on the safety range is the slope of the connecting line between the nodes; as shown in Figure 4 , E1 is the tracked trajectory line, E2 is the blade root initial position line, and E3 is the blade tip safety range line.

[0087] Embodiment 3

[0088] The embodiment provides a blade clearance control system based on blade posture judgment, which is used for implementing the blade clearance control method based on blade posture judgment in the embodiment 1 or the embodiment 2, and comprises the following steps of:

[0089] a collection module configured to collect blade movement information of a wind turbine;

[0090] a blade movement posture solving module configured to solve a blade movement posture according to the collected blade movement information;

[0091] a coordinate system and safety range threshold establishing module configured to establish a coordinate system and a safety range threshold according to the blade movement posture and the blade movement information;

[0092] a blade movement trajectory drawing module configured to draw a blade movement trajectory according to the blade movement information and the coordinate system;

[0093] a safety monitoring module configured to monitor a blade position according to the blade movement trajectory;

[0094] a clearance control module configured to send a clearance safety risk early warning to a wind turbine control module according to the monitored blade position, guide the wind turbine to pitch, and complete clearance control.

[0095] Embodiment 3

[0096] The embodiment discloses a non-transitory computer readable medium storing instructions, when the instructions are executed by a processor, the steps of the blade clearance control method based on blade posture judgment according to the embodiment 1 or the embodiment 2 are executed.

[0097] The non-transitory computer readable medium in the embodiment can be a disk, an optical disk, a computer memory, a read-only memory (ROM), a random access memory (RAM), a U disk, a mobile hard disk and the like.

[0098] Embodiment 4

[0099] The embodiment discloses a computing device comprising a processor and a memory for storing a processor executable program, when the processor executes the program stored in the memory, the blade clearance control method based on blade posture judgment according to the embodiment 1 or the embodiment 2 is implemented.

[0100] The computing device described in this embodiment can be a desktop computer, a notebook computer, a smart phone, a PDA handheld terminal, a tablet computer, a programmable logic controller (PLC), or other terminal device with processor function.

[0101] The above-described embodiments are only preferred embodiments of the present application, and are not intended to limit the scope of the present application. Any changes made in the shape or principle of the present application should be covered within the scope of the present application.

Claims

1. A blade clearance control method based on blade posture determination, characterized by, The method comprises the following steps: S1, collecting blade movement information of a wind turbine generator set; S2, solving a blade movement posture according to the collected blade movement information, comprising the following steps: Through the collected current blade movement information signal, the signal is subjected to white noise suppression and Kalman filtering signal processing, and the current blade movement posture is solved through a movement solving equation; The movement solving process presents the posture of an object in the form of a quaternion, and the formula is as follows: q = [q0, q1, q2, q3]; Wherein q0 is a scalar, which is 1 in the initial state, representing the cosine of half of the included angle θ of the current state relative to the standard state, and q1, q2 and q3 are vector coefficients, mainly reflecting the rotation change of the object in the three-dimensional space, which are 0 in the initial state; When the object generates motion, its attitude is considered to be a three-axis rotation process based on the original quaternion, so the angular velocity values of the three-axis motion of the object relative to the space are obtained, denoted as ω bx , ω by , and ω bz . According to the quaternion differential relationship between the angular velocity and the quaternion in the inertial motion system: In the formula Wherein The rotation of the quaternion is completed, and the change of the pitch angle, roll angle and yaw angle of the current object relative to the static state is obtained through the calculation, and the components of the gravitational acceleration are constructed to eliminate the influence of the gravitational acceleration in the integral calculation; S3, establishing a coordinate system and a safety range threshold value through the blade movement posture and the blade movement information, comprising the following steps: A coordinate system is created in a three-dimensional space, relative coordinate points in the space are drawn through the relative positions of multiple sensors, and the current yaw angle data of the wind turbine generator set and the design clearance distance parameter of the set are used to estimate the position of the sensor relative to the tower drum, to obtain the path estimation of the sensor during the yawing of the set, and to simulate the coordinate points, to confirm the initial position of the blade sensor before the start of the installed wind turbine generator set, to construct the static position of the blade, and to confirm the position of the safety range, to set the distance estimation movement path to be 0.4*design clearance distance of the set minus the design clearance distance of the set according to the path estimation result and the design clearance distance of the set. S4, drawing a blade movement trajectory according to the blade movement information and the coordinate system; S5, monitoring the blade position according to the blade movement trajectory to obtain a safety monitoring result; S6, returning the safety monitoring result to the wind turbine generator set, and if the blade position exceeds the safety range in the safety monitoring result, sending a clearance safety risk early warning to the control module of the wind turbine generator set to guide the pitch of the wind turbine generator set and complete the clearance control.

2. The blade clearance control method based on blade pose determination according to claim 1, characterized in that, The step S1 comprises the following steps: A sensor is installed at a predetermined position of the blade of the wind turbine generator set, and the current blade movement information is measured, the blade movement information comprising three-axis acceleration, three-axis angular velocity, altitude and Beidou geographic information.

3. The blade clearance control method based on blade pose determination according to claim 1, characterized in that, The step S4 comprises the following steps: During the continuous operation of the wind turbine generator set, the blade posture is continuously solved and the movement distance is continuously calculated according to the sensor movement information, and the accelerometer data needs to be processed as follows: S41, eliminating the gravitational acceleration of the accelerometer measurement result by analyzing the solved object posture; S42, eliminating the influence of the accelerometer by high-pass filtering to eliminate the influence of the blade vibration external factors on the accelerometer; S43, performing secondary median integration on the acceleration of each axis, the first median integration obtaining the linear velocity, the accelerometer being calibrated by the impeller rotation speed, and the second median integration obtaining the movement distance; The complete blade movement track data during the operation of the wind turbine generator is drawn in the algorithm coordinate system.

4. The blade clearance control method based on blade pose determination according to claim 1, characterized in that, The step S5 comprises the following steps: In the three-dimensional space of the algorithm, whether the blade position gradually approaches or has cut into the safety range surface during the operation of the wind turbine generator is calculated according to the blade movement track, and a safety monitoring result is obtained.

5. The blade clearance control method based on blade pose determination according to claim 1, characterized in that, The step S6 comprises the following steps: According to the safety monitoring result, the monitoring result is sent to the wind turbine generator, if the moving distance is within the safety range, no pitch is needed, and the wind turbine generator is normally operated according to the control instruction of the controller, if the moving distance exceeds the safety range, the clearance safety risk early warning is sent to the control module of the wind turbine generator, guiding the wind turbine generator to perform the pitch action, and completing the clearance control process.

6. A blade clearance control system based on blade pose determination, characterized by A blade clearance control method based on blade posture judgment for realizing any one of claims 1-5, comprising: An acquisition module for acquiring blade movement information of the wind turbine generator; A blade movement posture solving module for solving the blade movement posture according to the acquired blade movement information; A coordinate system and safety range threshold establishing module for establishing the coordinate system and the safety range threshold through the blade movement posture and the blade movement information; A blade movement track drawing module for drawing the blade movement track according to the blade movement information and the coordinate system; A safety monitoring module for monitoring the blade position according to the blade movement track; A clearance control module for sending the clearance safety risk early warning to the control module of the wind turbine generator according to the monitored blade position, guiding the wind turbine generator to pitch, and completing the clearance control.

7. A non-transitory computer-readable medium storing instructions, the method comprising: When the instructions are executed by the processor, the steps of the blade clearance control method based on the blade posture judgment according to any one of claims 1-5 are executed.

8. A computing device comprising a processor and a memory for storing processor-executable programs, characterized in that, When the processor executes the program stored in the memory, the blade clearance control method based on the blade posture judgment according to any one of claims 1-5 is realized.

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