A stall monitoring and control method and system for a wind turbine blade
By configuring a baseline curve to compare with the real-time operating data of the wind turbine, the accuracy problem of blade stall monitoring was solved, achieving the effect of safe operation and maximizing power generation.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- CRRC ZHUZHOU ELECTRIC LOCOMOTIVE RESEARCH INSTITUTE CO LTD
- Filing Date
- 2023-11-16
- Publication Date
- 2026-05-19
AI Technical Summary
Existing technologies are insufficient to accurately identify wind turbine blade stall, and adding sensor monitoring methods is not conducive to cost reduction and efficiency improvement.
By configuring wind turbine wind speed-active power and generator speed-nacelle acceleration curves under different air densities as benchmarks, and comparing them with real-time monitoring data, it is possible to determine whether the blades are stalling and control their state.
It enables accurate monitoring of blade stall and timely adjustments without increasing hardware costs, ensuring safe operation of the unit and maximizing power generation.
Smart Images
Figure CN117365870B_ABST
Abstract
Description
Technical Field
[0001] This invention mainly relates to the field of wind power technology, specifically to a method and system for monitoring and controlling stall of wind turbine blades. Background Technology
[0002] With the development and popularization of wind power technology, turbine manufacturers have gained a deeper understanding of the aerodynamic performance of wind turbines in recent years. When wind turbines operate under low air density conditions, the blades are prone to stall. When the entire turbine is in a stall state, it not only causes the full-load wind speed to shift backward, resulting in a significant loss of power generation, but also increases blade load due to stall flutter, affecting the safety of the unit. Therefore, accurately monitoring, identifying, and controlling blade stall phenomena can not only ensure power generation but also guarantee the safe operation of the unit.
[0003] Currently, there are two main methods for monitoring and identifying blade stall problems:
[0004] 1. Based on the relationship between lift coefficient and angle of attack, aerodynamic damping of blade elements and blade modes is calculated using aerodynamic forces to identify blade stall conditions. However, the actual relationship between lift coefficient and angle of attack in wind turbine operation differs significantly from the theoretical relationship, making it difficult for this method to accurately identify blade stall phenomena.
[0005] 2. By performing spectral analysis on the blade vibration signal or using turbulence sensors to monitor airflow separation on the blade, the stall state of the blade can be monitored. However, such methods require additional sensors, which is not conducive to reducing the cost and improving the efficiency of the entire wind turbine. Summary of the Invention
[0006] The technical problem to be solved by the present invention is: in view of the technical problems existing in the prior art, the present invention provides a low-cost method and system for monitoring and controlling the stall of wind turbine blades that maximizes power generation while ensuring the safe operation of the unit.
[0007] To solve the above-mentioned technical problems, the technical solution proposed by this invention is as follows:
[0008] A method for monitoring and controlling stall of wind turbine blades, comprising the following steps:
[0009] The wind turbine is pre-configured with wind speed-active power curves under different air densities as a reference wind speed-active power curve; the wind turbine is pre-configured with generator speed-nacelle acceleration curves under different air densities as a reference generator speed-nacelle acceleration curve.
[0010] Acquire wind turbine operating data, including air temperature, wind speed, power generation, generator speed, and nacelle acceleration;
[0011] The current air density is obtained from the air temperature; the current wind speed-active power curve of the wind turbine is obtained from the wind speed and power generation; the current generator speed-nacelle acceleration curve of the wind turbine is obtained from the generator speed and nacelle acceleration.
[0012] The current wind speed-active power curve is compared with the reference wind speed-active power curve under the current air density to obtain the first comparison result; at the same time, the current generator speed-nacelle acceleration curve is compared with the reference generator speed-nacelle acceleration curve under the current air density to obtain the second comparison result.
[0013] The first comparison result and the second comparison result are used to determine whether the wind turbine blades are stalling and the degree of stalling.
[0014] Preferably, when the first comparison result is that the current wind speed-active power curve exceeds the stall control threshold of the reference wind speed-active power curve under the current air density but is lower than the corresponding shutdown protection value, and the second comparison result is that the current generator speed-nacelle acceleration curve exceeds the stall control threshold of the reference generator speed-nacelle acceleration curve under the current air density but is lower than the corresponding shutdown protection value, then the blade is judged to be in a general stall.
[0015] Preferably, when the blade is determined to be in a general stall state, the additional value of the pitch angle is calculated by combining the current pitch angle and the active power, and then superimposed on the unified pitch output value to perform the pitch retraction action.
[0016] Preferably, if the first comparison result is that the current wind speed-active power curve exceeds the shutdown protection value of the reference wind speed-active power curve, or if the second comparison result is that the current generator speed-nacelle acceleration curve exceeds the shutdown protection value of the reference generator speed-nacelle acceleration curve under the current air density, then the blade is judged to be in severe stall.
[0017] Preferably, when the blades are determined to be in severe stall, a shutdown action is performed.
[0018] Preferably, after acquiring the operating data of the wind turbine, the operating data is cleaned: bandpass filtering is performed on each of the obtained operating data, and then sliding filtering is performed to obtain effective operating data.
[0019] Preferably, when the wind speed-active power curves of the wind turbine under different air densities and the generator speed-nacelle acceleration curves of the wind turbine under different air densities are pre-configured, the operating data in the SCADA monitoring system is used as the raw data.
[0020] Preferably, a cluster of wind speed-active power curves under different air densities is obtained from the operating data of the SCADA monitoring system, and a specific wind speed-active power curve is estimated based on the current air density, which is then used as the reference wind speed-active power curve.
[0021] The generator speed-nacelle acceleration curves under different air densities are obtained from the operating data of the SCADA monitoring system. The specific generator speed-nacelle acceleration curve is estimated based on the current air density and used as the benchmark generator speed-nacelle acceleration curve.
[0022] The present invention also discloses a computer-readable storage medium having a computer program stored thereon, the computer program performing the steps of the method described above when run by a processor.
[0023] The present invention further discloses a wind turbine blade stall monitoring and control system, including a memory and a processor connected to each other. The memory stores a computer program, which executes the steps of the method described above when run by the processor.
[0024] Compared with the prior art, the advantages of the present invention are as follows:
[0025] This invention monitors blade stall status in real time based on real-time monitoring data of wind turbine operation, ensuring that the unit can make timely adjustments according to the current operating status. This maximizes power generation while ensuring safe operation and fully taps the power generation potential. The above process is actively judged and executed by the main control program, requiring no additional hardware costs and achieving load reduction at a lower cost. Attached Figure Description
[0026] Figure 1 This is a flowchart of an embodiment of the control method of the present invention.
[0027] Figure 2 The flowcharts for the various reference curve generation methods in this invention are shown in the embodiments.
[0028] Figure 3 This is a flowchart of the logical judgment process in this invention.
[0029] Figure 4 This is a schematic diagram of the wind speed-active power curve in this invention.
[0030] Figure 5 This is a schematic diagram of the generator speed-nacelle acceleration curve in this invention.
[0031] Figure 6 This is a schematic diagram of the threshold corresponding to the generator speed-nacelle acceleration curve in this invention. Detailed Implementation
[0032] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.
[0033] like Figure 1 As shown, the wind turbine blade stall monitoring and control method of this invention includes the following steps:
[0034] The wind turbine is pre-configured with wind speed-active power curves under different air densities as a reference wind speed-active power curve; the wind turbine is pre-configured with generator speed-nacelle acceleration curves under different air densities as a reference generator speed-nacelle acceleration curve.
[0035] The operation data of the wind turbine is acquired and cleaned. Specifically, bandpass filtering is performed on each data point, followed by 100ms sliding filtering to obtain the effective data for each variable. The operation data includes air temperature, wind speed, power generation, generator speed, and nacelle acceleration.
[0036] The current air density is obtained from the air temperature; the current wind speed-active power curve of the wind turbine is obtained from the wind speed and power generation; the current generator speed-nacelle acceleration curve of the wind turbine is obtained from the generator speed and nacelle acceleration.
[0037] The current wind speed-active power curve is compared with the reference wind speed-active power curve under the current air density to obtain the first comparison result; at the same time, the current generator speed-nacelle acceleration curve is compared with the reference generator speed-nacelle acceleration curve under the current air density to obtain the second comparison result.
[0038] The first comparison result and the second comparison result are used to determine whether the wind turbine blades are stalling and the degree of stalling.
[0039] Specifically, when the first comparison result is that the current wind speed-active power curve exceeds the stall control threshold of the reference wind speed-active power curve under the current air density but is lower than the corresponding shutdown protection value, and the second comparison result is that the current generator speed-nacelle acceleration curve exceeds the stall control threshold of the reference generator speed-nacelle acceleration curve under the current air density but is lower than the corresponding shutdown protection value, then the blade is judged to be in a general stall. At this time, the additional value of the pitch angle is calculated by combining the current pitch angle and active power, and superimposed on the unified pitch output value to perform the pitch retraction action.
[0040] If the first comparison result is that the current wind speed-active power curve exceeds the shutdown protection value of the reference wind speed-active power curve, or if the second comparison result is that the current generator speed-nacelle acceleration curve exceeds the shutdown protection value of the reference generator speed-nacelle acceleration curve under the current air density, then the blade is judged to be in severe stall, and a shutdown action is executed.
[0041] In general, the stall judgment condition is that the first comparison result and the second comparison result simultaneously reach the stall control threshold but are lower than the shutdown protection value, then control action is taken; in case of severe stall, either of the two conditions reaches the shutdown protection value, then the machine is shut down.
[0042] The above process is actively judged and executed by the main control program, and corresponding scheduling and control actions are performed without increasing other hardware costs, so that the load reduction effect can be achieved at a lower cost.
[0043] This invention monitors the blade stall status in real time based on real-time monitoring data of wind turbine operation, ensuring that the unit can make timely adjustments according to the current operating status, maximizing power generation while ensuring safe operation of the unit, and fully tapping the power generation potential.
[0044] This invention also provides a wind turbine stall monitoring and control device, specifically including a big data real-time monitoring module, a data processing module, a logic judgment module, a control module, and a protection module;
[0045] The big data real-time monitoring module is used to acquire wind turbine operation data from the SCADA monitoring system to ensure data accuracy;
[0046] The data processing module receives SCADA data input and then uses a 100ms sliding filter to calculate the average value, thus avoiding significant impact of data fluctuations on the control system.
[0047] In addition, the data processing module also needs to calculate the wind speed-active power curve database and the generator speed-nacelle acceleration database, as follows:
[0048] 1. Calculate historical air density using cleaned temperature data;
[0049] 2. A wind speed-active power curve database is established based on historical air density, wind speed, and active power data to generate wind speed-active power curves under different air densities. These curves serve as the benchmark curves for logical judgments. A specific example of a wind speed-active power curve is shown below. Figure 4 As shown; specifically, a cluster of wind speed-active power curves under different air densities can be obtained from past operational big data, and the specific wind speed-active power curve can be estimated based on the current air density, which can be used as the benchmark wind speed-active power curve.
[0050] 3. Establish a generator speed-nacelle acceleration database based on historical air density, generator speed, nacelle acceleration, and other data. This database generates generator speed-nacelle acceleration envelopes under different air densities, serving as the acceleration baseline for logical judgments. A specific example of a generator speed-nacelle acceleration curve is shown below. Figure 5As shown; specifically, a cluster of generator speed-nacelle acceleration curves under different air densities can be obtained from the big data of past unit operation, and the specific generator speed-nacelle acceleration envelope can be estimated based on the current air density, and used as the benchmark generator speed-nacelle acceleration envelope;
[0051] The logic judgment module is used to compare the current unit operating data with the above-mentioned benchmark curves. Specifically, it compares the current unit wind speed-active power curve with the benchmark wind speed-active power curve under the current air density to obtain the first comparison result. The benchmark wind speed-active power curve corresponds to the stall control threshold and the shutdown protection threshold.
[0052] Simultaneously, the current generator speed-nacelle acceleration curve is compared with the baseline generator speed-nacelle acceleration curve under the current density to obtain a second comparison result; the baseline generator speed-nacelle acceleration curve corresponds to stall control thresholds and shutdown protection thresholds; such as Figure 6 As shown, the corresponding red line is the reference generator speed-nacelle acceleration curve; the blue line is the stall control threshold; and the black line is the shutdown protection threshold.
[0053] If the first comparison result is that the current wind speed-active power curve exceeds the stall control threshold of the reference wind speed-active power curve under the current air density but is lower than the corresponding shutdown protection value, and the second comparison result is that the current generator speed-nacelle acceleration curve exceeds the stall control threshold of the reference generator speed-nacelle acceleration curve under the current air density but is lower than the corresponding shutdown protection value, then the blade is judged to be in a general stall. At this time, the control module calculates the pitch angle additional value by combining the current pitch angle and active power, and adds it to the unified pitch output value to perform the pitch retraction action.
[0054] If the first comparison result is that the current wind speed-active power curve exceeds the shutdown protection value of the reference wind speed-active power curve, and the second comparison result is that the current generator speed-nacelle acceleration curve exceeds the shutdown protection value of the reference generator speed-nacelle acceleration curve under the current air density, then the blade is judged to be in severe stall, and the protection module will execute the shutdown action.
[0055] To avoid control malfunctions, the stall control thresholds mentioned above need to be set with hysteresis, resulting in high control reliability and fewer malfunctions.
[0056] This invention also discloses a computer-readable storage medium storing a computer program thereon, which, when run by a processor, performs the steps of the method described above. This invention further discloses a wind turbine blade stall monitoring and control system, including a memory and a processor interconnected, wherein the memory stores a computer program, which, when run by a processor, performs the steps of the method described above. The medium and system of this invention, corresponding to the methods described above, also possess the advantages described above.
[0057] The present invention can implement all or part of the processes in the methods of the above embodiments, or it can be implemented by hardware related to computer program instructions. The computer program can be stored in a computer-readable storage medium. When the computer program is executed by a processor, it can implement the steps of the above method embodiments. The computer program includes computer program code, which can be in the form of source code, object code, executable file, or some intermediate form. The computer-readable storage medium includes: any entity or device capable of carrying computer program code, recording media, USB flash drive, portable hard drive, magnetic disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signals, telecommunication signals, and software distribution media, etc. The memory is used to store computer programs and / or modules. The processor implements various functions by running or executing the computer programs and / or modules stored in the memory, and by calling data stored in the memory. The memory may include high-speed random access memory, as well as non-volatile memory, such as hard disks, RAM, plug-in hard disks, smart media cards (SMC), secure digital (SD) cards, flash cards, at least one disk storage device, flash memory device, or other volatile solid-state storage devices.
[0058] The above are merely preferred embodiments of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principles of the present invention should be considered within the scope of protection of the present invention.
Claims
1. A method for monitoring and controlling stall of wind turbine blades, characterized in that, Including the following steps: The wind speed-active power curves of the wind turbine under different air densities are pre-configured as the reference wind speed-active power curves; The generator speed-nacelle acceleration curves of the wind turbine under different air densities are pre-configured as the reference generator speed-nacelle acceleration curves; Acquire wind turbine operating data, including air temperature, wind speed, power generation, generator speed, and nacelle acceleration; The current air density is obtained based on the temperature. The current wind speed-active power curve of the wind turbine is obtained based on wind speed and power generation; the current generator speed-nacelle acceleration curve of the wind turbine is obtained based on generator speed and nacelle acceleration. The current wind speed-active power curve is compared with the reference wind speed-active power curve under the current air density to obtain the first comparison result; at the same time, the current generator speed-nacelle acceleration curve is compared with the reference generator speed-nacelle acceleration curve under the current air density to obtain the second comparison result. The first comparison result and the second comparison result are used to determine whether the wind turbine blades are stalling and the corresponding degree of stalling. If the first comparison result is that the current wind speed-active power curve exceeds the stall control threshold of the reference wind speed-active power curve under the current air density but is lower than the corresponding shutdown protection value, and the second comparison result is that the current generator speed-nacelle acceleration curve exceeds the stall control threshold of the reference generator speed-nacelle acceleration curve under the current air density but is lower than the corresponding shutdown protection value, then the blade is judged to be in a general stall. If the first comparison result is that the current wind speed-active power curve exceeds the shutdown protection value of the reference wind speed-active power curve, or if the second comparison result is that the current generator speed-nacelle acceleration curve exceeds the shutdown protection value of the reference generator speed-nacelle acceleration curve under the current air density, then the blade is judged to be in severe stall.
2. The wind turbine blade stall monitoring and control method according to claim 1, characterized in that, When the blade is determined to be in a normal stall state, the additional value of the pitch angle is calculated by combining the current pitch angle and active power, and then superimposed on the unified pitch output value to perform the pitch retraction action.
3. The wind turbine blade stall monitoring and control method according to claim 1, characterized in that, When the blades are determined to be in severe stall, a shutdown procedure is executed.
4. The wind turbine blade stall monitoring and control method according to any one of claims 1-3, characterized in that, After acquiring the operating data of the wind turbine, the data is cleaned: bandpass filtering is performed on each piece of operating data, followed by sliding filtering, to obtain effective operating data.
5. The wind turbine blade stall monitoring and control method according to any one of claims 1-3, characterized in that, When pre-configuring the wind speed-active power curves of wind turbines under different air densities, and the generator speed-nacelle acceleration curves of wind turbines under different air densities, the operating data in the SCADA monitoring system is used as the raw data.
6. The wind turbine blade stall monitoring and control method according to claim 5, characterized in that, The wind speed-active power curve clusters under different air densities are obtained from the operating data of the SCADA monitoring system, and the specific wind speed-active power curve is estimated based on the current air density and used as the reference wind speed-active power curve. The generator speed-nacelle acceleration curves under different air densities are obtained from the operating data of the SCADA monitoring system. The specific generator speed-nacelle acceleration curve is estimated based on the current air density and used as the benchmark generator speed-nacelle acceleration curve.
7. A computer-readable storage medium having a computer program stored thereon, characterized in that, The computer program, when run by a processor, performs the steps of the method as described in any one of claims 1-6.
8. A wind turbine blade stall monitoring and control system, comprising a memory and a processor interconnected, wherein the memory stores a computer program, characterized in that, The computer program, when run by a processor, performs the steps of the method as described in any one of claims 1-6.