CN113494429B - Method for monitoring pneumatic imbalance of fan blade - Google Patents
Method for monitoring pneumatic imbalance of fan blade Download PDFInfo
- Publication number
- CN113494429B CN113494429B CN202110706642.3A CN202110706642A CN113494429B CN 113494429 B CN113494429 B CN 113494429B CN 202110706642 A CN202110706642 A CN 202110706642A CN 113494429 B CN113494429 B CN 113494429B
- Authority
- CN
- China
- Prior art keywords
- blades
- blade
- lmb
- lma
- theta
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
- F03D—WIND MOTORS
- F03D17/00—Monitoring or testing of wind motors, e.g. diagnostics
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/70—Wind energy
- Y02E10/72—Wind turbines with rotation axis in wind direction
Landscapes
- Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Sustainable Development (AREA)
- Sustainable Energy (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Wind Motors (AREA)
- Aerodynamic Tests, Hydrodynamic Tests, Wind Tunnels, And Water Tanks (AREA)
Abstract
The invention discloses a method for monitoring the pneumatic imbalance of a fan blade, which comprises the steps of firstly selecting two mounting points in the root area of each blade of a fan, mounting a load sensor on each mounting point, measuring the load of the two mounting points of the three blades at different wind speeds v through the load sensors, measuring the real-time azimuth angles theta of the three blades, measuring the gravity of the three blades, substituting the measured data into a formula to obtain the aerodynamic force Fx of the three blades at different wind speeds v, fitting a v-Fx curve according to the aerodynamic force Fx of each blade at different wind speeds v, finally drawing the obtained three curves in a graph, comparing the three curves, and if the three curves are approximate or coincident, indicating that the three blades are in a pneumatic balanced state, otherwise indicating that the blades are in a pneumatic imbalance state. By the method, whether the blades are in a pneumatic unbalanced state or not can be found in time, and the problem that the service life and the operation safety of a unit are influenced due to the increase of the load of the whole machine caused by the pneumatic imbalance of the blades is solved.
Description
Technical Field
The invention relates to the technical field of fan blade pneumatic unbalance monitoring, in particular to a fan blade pneumatic unbalance monitoring method.
Background
With the continuous development of wind power technology, the output power of a wind turbine generator becomes larger, a tower is higher, blades are longer, and the running environment of the wind turbine generator is more complex, so that the unbalanced fault of a wind wheel caused by unbalanced mass and unbalanced pneumatics of the blades becomes a serious problem of threatening the safe running of the wind turbine generator and influencing the performance of the wind turbine generator.
At present, the mass unbalance can be diagnosed quickly and the blade balancing can be carried out again by using a conventional diagnosis mode. However, the pneumatic unbalance fault is not easy to find in the early stage, and the conventional diagnosis method is difficult to judge whether the pneumatic unbalance is caused or not and how large the unbalance difference of the three blades is.
The main reasons for the aerodynamic imbalance of the blades are:
1) Manufacturing errors of the blade: 0 degree positioning error in blade manufacturing; 2) Blade installation error: certain measurement errors exist in the calibration of the blade installation angle; 3) The variable pitch mechanism has the following execution error: the angles of all the blades cannot be completely synchronized in the variable pitch process, so that an execution error is generated; 4) The damage state of the blade: when a certain blade is damaged, the stress of each blade is different, and the pneumatic imbalance is generated.
Influence of aerodynamic imbalance of the blades: 1) The periodic load of the fan increases; 2) The vibration of the fan is increased; 3) Damage is generated to parts in the fan, such as a main shaft, yaw, pitch damage and the like; 4) The generated energy of the fan is reduced.
The conventional blade aerodynamic imbalance detection method is to judge whether imbalance exists or not by analyzing a vibration signal of a cabin or judge whether wind power is balanced or not by adopting imaging of blades on the ground, but the methods need to analyze and compare historical data of a unit, have large data volume and complex calculation, need certain experience of vibration analysis and image processing technology, and have the characteristic quantity analyzed as an indirect result and are difficult to directly reflect the problem of aerodynamic imbalance of the blades. And due to the random change of the wind conditions, reliable similar working conditions are difficult to select for comparative analysis.
Finally, there is a need for a simple and straightforward method of determining pneumatic imbalances.
Disclosure of Invention
The invention aims to overcome the defects in the prior art, and provides a simple, convenient, direct and effective method for monitoring the pneumatic imbalance of the fan blade.
In order to achieve the purpose, the technical scheme provided by the invention is as follows: a method for monitoring the aerodynamic imbalance of a fan blade comprises the steps of firstly selecting two mounting points a and b in the root area of each blade of a fan, then measuring the distances between the mounting points a and b and the starting point of the blade root LMa and LMb, then mounting a load sensor on each mounting point, measuring the loads Ma and Mb of the mounting points a and b of the three blades under different wind speeds v through the load sensors, then respectively measuring the real-time azimuth angle theta of the three blades and the gravity G of the three blades, and substituting the measured Ma, mb, LMa, LMb, G and theta into a formula (1):
Mb-Ma＝G×f(θ)×(LMa-LMb)+Fx(LMa-LMb) (1)
in the formula, f (theta) is a gravity component function of the azimuth angle of the blade, the azimuth angles of the three blades sequentially differ by 120 degrees, and Fx is aerodynamic force of the blade;
obtaining aerodynamic force Fx of the three blades at different wind speeds v according to a formula (1), further fitting a v-Fx curve according to the aerodynamic force Fx of each blade at different wind speeds v, finally drawing the three obtained curves in a graph, comparing the three curves, and if the three curves are approximate or coincident, indicating that the three blades are in a pneumatic balance state, otherwise indicating that the blades are in a pneumatic unbalance state.
Further, the derivation process of equation (1) is as follows:
the loads at the two mounting points a and b of the blade are Ma and Mb respectively, the gravity of the blade is G, the gravity center is LG, the aerodynamic force is Fx, the aerodynamic torque is LF, and the blade can be known according to a balance formula of the torque:
Ma＝G×(LG-LMa)×f(θ)+Fx(LF-LMa) (2)
Mb＝G×(LG-LMb)×f(θ)+Fx(LF-LMb) (3)
in the formula, f (theta) is a gravity component function of the azimuth angle of the blade, wherein the azimuth angles of three blades of the fan are sequentially different by 120 degrees;
the following is derived from equation (2) and equation (3):
Mb-Ma＝G×f(θ)×(LMa-LMb)+Fx(LMa-LMb)。
further, the method for measuring the real-time azimuth theta of the three blades comprises the following steps: the real-time azimuth angle of any blade is measured, and the difference between the azimuth angles of three blades is 120 degrees in sequence, so that the azimuth angles of the other two blades are obtained.
Compared with the prior art, the invention has the following advantages and beneficial effects:
the monitoring method has the advantages of simplicity, convenience, directness, effectiveness and the like, and can judge whether the blade is in a pneumatic unbalanced state or not by only installing two load sensors on the blade root of the blade and combining simple calculation steps and comparing, quantizing and directly, thereby avoiding the problems of influencing the service life and the operation safety of a unit, further reducing the annual energy production of a fan, reducing the economic benefit and the like due to the increase of the load of the whole machine caused by the pneumatic imbalance of the blade.
Drawings
Fig. 1 is a force-bearing schematic diagram of a fan blade.
FIG. 2 is a schematic view of a θ -M curve.
FIG. 3 is a graph comparing the v-Fx curves of three blades obtained by the method of the present invention.
Detailed Description
The present invention is further illustrated with reference to the following specific examples, but the mode of use of the present invention is not limited thereto.
According to the method for monitoring the aerodynamic imbalance of the fan blade, firstly, two mounting points a and b are selected in the root area of each blade of the fan, as shown in fig. 1, the distances between the two mounting points and the starting point of the blade root are respectively LMa and LMb, the loads at the two mounting points are respectively Ma and Mb, the gravity of the blade is G, the gravity center is LG, the aerodynamic force is Fx, and the aerodynamic moment is LF;
according to the balance formula of the moment, the following formula is obtained:
Ma＝G×(LG-LMa)×f(θ)+Fx(LF-LMa) (2)
Mb＝G×(LG-LMb)×f(θ)+Fx(LF-LMb) (3)
in the formula, f (theta) is a gravity component function of the azimuth angle of the blade, wherein the azimuth angles of three blades of the fan are sequentially different by 120 degrees;
deriving equation (1) from equation (2) and equation (3):
Mb-Ma＝G×f(θ)×(LMa-LMb)+Fx(LMa-LMb)
taking Mb-Ma in equation (1) as signal M, the equation can be transformed into:
M＝A×f(θ)+B (4)
wherein parameter a = G (LMa-LMb), parameter B = Fx (LMa-LMb);
the formula (4) is a function related to a theta-M curve, the characteristic of the curve is shown in figure 2, a parameter A is a signal amplitude of a gravity moment influencing the theta-M curve, meanwhile, the difference between LMa and LMb of three blades is equal, the signal amplitude of the gravity G influencing the theta-M curve of the blade is finally obtained, a parameter B is a signal offset of the aerodynamic moment influencing the theta-M curve, and meanwhile, the difference between LMa and LMb of three blades is equal, and the signal offset of the aerodynamic force Fx influencing the theta-M curve of the blade is finally obtained. Therefore, when the gravity G of the three blades is balanced and the aerodynamic force Fx is unbalanced, the aerodynamic moments of the three blades are different, so that the signal offset of the three theta-M curves is different; when the gravity G is unbalanced and the aerodynamic force Fx is balanced, the different gravity moments of the three blades lead to different signal amplitudes of the three theta-M curves; therefore, the difference of the blade aerodynamic imbalance state is compared, and only the signal offset of the blade under the aerodynamic moment is evaluated.
Based on the principle, a load sensor is respectively arranged on the mounting points a and b of each blade, then the distances LMa and LMb between the mounting points a and b and the starting point of the blade root of the blade are measured, then the loads Ma and Mb of the mounting points a and b of the three blades under different wind speeds v are measured through the load sensors, then the real-time azimuth angle theta of one blade is measured, the azimuth angles of the other two blades can be calculated according to the azimuth angle theta of the blade, the gravity G of the three blades is measured, and the measured Ma, mb, LMa, LMb, G and theta are substituted into the formula:
Mb-Ma＝G×f(θ)×(LMa-LMb)+Fx(LMa-LMb) (1)
in the formula, f (theta) is a gravity component function of the azimuth angles of the blades, the azimuth angles of the three blades sequentially differ by 120 degrees, and Fx is aerodynamic force of the blades;
obtaining signal offset of three blades at different wind speeds v according to a formula (1), namely Fx (LMa-LMb), further calculating aerodynamic force Fx according to the known Fx (LMa-LMb) and LMa-LMb, then fitting a v-Fx curve according to the aerodynamic force Fx of each blade at different wind speeds v, finally drawing the obtained three curves in a graph, as shown in figure 3, comparing the three curves, if the three curves are close or overlapped, representing that three blades are in aerodynamic balance, if one curve is larger than the other two curves, representing that one blade is in an aerodynamic unbalanced state, and if the three curves are larger in average difference, representing that the three blades are in an aerodynamic unbalanced state.
The above-mentioned embodiments are merely preferred embodiments of the present invention, and the scope of the present invention is not limited thereto, so that variations based on the shape and principle of the present invention should be covered within the scope of the present invention.
Claims (2)
1. A method for monitoring the aerodynamic imbalance of a fan blade is characterized by comprising the following steps of firstly, selecting two mounting points a and b in the root area of each blade of a fan, setting the distances between the two mounting points and the starting point of the blade root as LMa and LMb respectively, setting the loads at the two mounting points as Ma and Mb respectively, setting the gravity of the blade as G, the gravity center as LG, the aerodynamic force as Fx and the aerodynamic moment as LF;
according to the balance formula of the moment, the following results are obtained:
Ma＝G×(LG-LMa)×f(θ)+Fx(LF-LMa) (2)
Mb＝G×(LG-LMb)×f(θ)+Fx(LF-LMb) (3)
in the formula, f (theta) is a gravity component function of the azimuth angle of the blade, wherein the azimuth angles of three blades of the fan are sequentially different by 120 degrees;
deriving equation (1) from equation (2) and equation (3):
Mb-Ma＝G×f(θ)×(LMa-LMb)+Fx(LMa-LMb) (1)
taking Mb-Ma in equation (1) as signal M, the equation is modified as:
M＝A×f(θ)+B (4)
wherein parameter a = G (LMa-LMb), parameter B = Fx (LMa-LMb);
the formula (4) is a function related to a theta-M curve, the parameter A is the signal amplitude of the gravity moment influencing the theta-M curve, the signal amplitude of the gravity G influencing the theta-M curve of the blade is obtained due to the equal difference of LMa-LMb of the three blades, the parameter B is the signal offset of the aerodynamic moment influencing the theta-M curve, meanwhile, the signal offset of the aerodynamic force Fx influencing the theta-M curve of the blade is finally obtained due to the equal difference of LMa-LMb of the three blades, and the signal offset is deduced: when the gravity G of the three blades is balanced and the aerodynamic force Fx is unbalanced, the aerodynamic moments of the three blades are different, so that the signal offsets of the three theta-M curves are different; when the gravity G is unbalanced and the aerodynamic force Fx is balanced, the different gravity moments of the three blades lead to different signal amplitudes of the three theta-M curves; therefore, the difference of the blades in the aerodynamic imbalance state is compared, and only the signal offset of the blades under the aerodynamic moment is evaluated;
based on the principle, the distances LMa and LMb between the mounting points a and b and the starting point of the blade root of each blade of the fan are measured in the root area of each blade, a load sensor is mounted on each mounting point, the loads Ma and Mb of the mounting points a and b of the three blades at different wind speeds v are measured through the load sensors, then the real-time azimuth angles theta of the three blades and the gravity G of the three blades are respectively measured, and the measured Ma, mb, LMa, LMb, G and theta are substituted into the formula (1):
Mb-Ma＝G×f(θ)×(LMa-LMb)+Fx(LMa-LMb) (1)
in the formula, f (theta) is a gravity component function of the azimuth angle of the blade, the azimuth angles of the three blades sequentially differ by 120 degrees, and Fx is aerodynamic force of the blade;
obtaining aerodynamic force Fx of the three blades at different wind speeds v according to a formula (1), fitting a v-Fx curve according to the aerodynamic force Fx of each blade at different wind speeds v, finally drawing the three obtained curves in a graph, comparing the three curves, and if the three curves are approximate or coincident, indicating that the three blades are in a pneumatic balance state, otherwise indicating that the blades are in a pneumatic unbalance state.
2. The method for monitoring the aerodynamic imbalance of the fan blade according to claim 1, wherein the method for measuring the real-time azimuth angle θ of the three blades comprises the following steps: the real-time azimuth angle of any blade is measured, and the difference between the azimuth angles of three blades is 120 degrees in sequence, so that the azimuth angles of the other two blades are obtained.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110706642.3A CN113494429B (en) | 2021-06-24 | 2021-06-24 | Method for monitoring pneumatic imbalance of fan blade |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110706642.3A CN113494429B (en) | 2021-06-24 | 2021-06-24 | Method for monitoring pneumatic imbalance of fan blade |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113494429A CN113494429A (en) | 2021-10-12 |
| CN113494429B true CN113494429B (en) | 2022-11-01 |
Family
ID=77997725
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110706642.3A Active CN113494429B (en) | 2021-06-24 | 2021-06-24 | Method for monitoring pneumatic imbalance of fan blade |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113494429B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114627115B (en) * | 2022-05-13 | 2022-08-30 | 济宁安泰矿山设备制造有限公司 | A dynamic balance detection system and a fluid pump impeller production line using the same |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR3027667B1 (en) * | 2014-10-22 | 2020-10-09 | Snecma | METHOD AND DEVICE FOR MONITORING A BLADED WHEEL OF AN AIRCRAFT ENGINE BY MEASURING THE BALANCE POSITION |
| DE102018001270A1 (en) * | 2018-02-19 | 2019-08-22 | Senvion Gmbh | Method and system for calibrating an anemotropometer |
| CN109653963B (en) * | 2018-12-26 | 2020-07-28 | 三一重能有限公司 | Blade dynamic balance evaluation method, device and system |
| CN110118152B (en) * | 2019-06-14 | 2020-07-28 | 三一重能有限公司 | Pneumatic balance monitoring and adjusting system and method for blades of wind generating set |
| CN110259637B (en) * | 2019-06-25 | 2021-03-23 | 中国船舶重工集团海装风电股份有限公司 | Pneumatic unbalance correction method, device and equipment for blades of wind generating set |
-
2021
- 2021-06-24 CN CN202110706642.3A patent/CN113494429B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN113494429A (en) | 2021-10-12 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US9567869B2 (en) | Wind turbine system for detection of blade icing | |
| CN1707262B (en) | Methods and apparatus for rotor blade ice detection | |
| CN102980651B (en) | Monitoring method and monitoring device and monitoring system of wind turbine generator condition | |
| CN104075795B (en) | Method and system for monitoring the state of vibration of an impeller of a wind power plant | |
| US10036692B2 (en) | System and method for estimating rotor blade loads of a wind turbine | |
| US9004862B2 (en) | Calibration of wind turbine sensor | |
| US20100004878A1 (en) | Wind turbine monitoring | |
| CN113323816A (en) | Blade detection method based on blade load analysis | |
| CN110118152B (en) | Pneumatic balance monitoring and adjusting system and method for blades of wind generating set | |
| CN105604806B (en) | Wind turbine tower condition monitoring method and system | |
| US11422052B2 (en) | System and method for diagnosing a rotor unbalance of a wind turbine | |
| US8820149B2 (en) | Method for oscillation measurement on rotor blades or wind power installations | |
| US11098698B2 (en) | System and method for auto-calibrating a load sensor system of a wind turbine | |
| CN102678453A (en) | Method and arrangement for detecting blade pitch angle misalignment of rotor blade system of wind turbine | |
| CN104995402A (en) | Detecting blade structure abnormalities | |
| CN109387345A (en) | A kind of simulation mistuned bladed disk and test device and method containing dry damping structure | |
| EP3642481B1 (en) | A method for determining wind turbine blade edgewise load recurrence | |
| US20230366382A1 (en) | Abnormality determination method for wind power generation device, abnormality determination system for wind power generation device, and abnormality determination program for wind power generation device | |
| CN113494429B (en) | Method for monitoring pneumatic imbalance of fan blade | |
| CN106323548A (en) | Double vibration sensor-based rotor imbalance vibration response identification method | |
| CN113357097B (en) | Blade clamping detection method and device for wind generating set | |
| CN115380160A (en) | Frequency Content Based Monitoring of Wind Turbine Blade Pitch Systems | |
| CN205669464U (en) | A kind of impeller of wind turbine set imbalance test system | |
| CN209838604U (en) | Wind turbine blade stress-strain testing device based on rotating platform | |
| CN117329085A (en) | An online diagnosis method, system and device for the unbalanced state of a wind turbine |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |