Fan blade clearance distance detection method

Abstract

The invention relates to the technical field of fan blade clearance distance detection, in particular to a fan blade clearance distance detection method, which is characterized in that a laser clearance radar is mounted at the bottom of a cabin cover, a transmitting end of the laser clearance radar transmits a light pulse to the direction of a blade, and the light pulse forms a return light pulse after encountering the fan blade; the internal timer calculates the distance between the laser clearance radar and the blade by recording the time difference of light pulse transmitting and receiving, the master controller obtains data of the distance between the laser clearance radar and the blade measured by the distance measuring module and sends the data to the fan master controller, and the distance between the laser clearance radar and the blade is smaller than the set safety distance. According to the method, monitoring of the clearance distance from the tower drum to the blade tip is more stable and reliable, the clearance distance can be accurately monitored in real time, the collision accident of the blade and the tower drum is effectively avoided, safe operation of the fan is guaranteed, and the maintenance risk is greatly reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of fan blade clearance distance detection, and in particular to a fan blade clearance distance detection method. Background Art

[0002] With the advancement of wind turbine technology and the improvement of energy efficiency requirements, long blades and high towers have become the development direction of wind turbines. Under the same wind speed, longer blades can increase the wind sweeping area and thus increase power generation. However, the increase in blade length makes the blades easier to bend. Under complex wind conditions or extreme weather conditions, the blades will produce angle deviations due to uneven force. If the clearance value between the tip of the blade and the wind turbine tower is less than the safe distance, it will not only affect the performance and benefits of the wind turbine, but also easily cause safety accidents such as tower sweeping. In the prior art, for such situations, the distance between the blade and the tower is often increased or flexible blades are used to avoid tower sweeping accidents. However, no matter which method is used, it is impossible to monitor the running blades in real time and feedback information to avoid tower sweeping accidents.

[0003] Therefore, how to monitor the clearance distance of the running blades and feed back the monitoring information to avoid the occurrence of tower sweeping accidents has become a technical problem that needs to be solved urgently by technical personnel in this field. Summary of the invention

[0004] The present invention provides a method for detecting the clearance distance of fan blades, which is used to solve the problem of how to monitor the clearance distance of running blades and feed back the monitoring information, thereby avoiding the occurrence of tower sweeping accidents.

[0005] The present invention provides a method for detecting the clearance distance of fan blades, comprising the following steps: S1. Install a laser clearance radar at the bottom of the cabin cover; S2. The transmitting end of the laser clearance radar emits a light pulse in the direction of the blade. When the light pulse encounters the wind turbine blade, it forms a return light pulse, which is received and amplified by the receiving lens and sent to the optical receiving module. The internal timer records the time difference between the emission and reception of the light pulse and calculates the distance between the laser clearance radar and the blade based on the principle of constant light speed. S3, the main control obtains the data of the distance between the laser clearance radar and the blades measured by multiple ranging modules, and sends it to the wind turbine main control after processing and algorithm analysis; S4: If the distance between the laser clearance radar and the blade is less than the set safety distance, the main control stops the fan and issues an alarm. If the distance between the laser clearance radar and the blade is greater than the set safety distance, the fan continues to run, the laser clearance radar continues to detect, and feeds back the distance between the laser clearance radar and the blade.

[0006] In some of these embodiments, the detection end of the laser clearance radar is flush with the lowest end of the rotation of the blade tip.

[0007] In some of these embodiments, the laser clearance radar is composed of three single-line ranging modules to form a three-line laser ranging radar.

[0008] In some of these embodiments, installing the laser clearance radar includes the following steps: S11. Taking the center of the tower barrel as the origin, the Y-axis as the direction of the main shaft of the generator, the X-axis passing through the center of the tower barrel and perpendicular to the Y-axis, and (x, y) being the horizontal installation position of the laser clearance radar, determine the installation position of the laser clearance radar through the laser clearance radar calibration assistant and the inclinometer; S12. Place the nacelle interface bracket at the determined installation position of the laser clearance radar on the nacelle cover, mark the opening position, and then draw a line; S13. Drill holes near the center of the marked area, then pass the anti-fall rope through and fix it, then drill holes at the four corners of the marked area, cut according to the marked line, and remove the plate; S14. Place the nacelle interface bracket at the corresponding position of the nacelle opening and install it, and install the laser clearance radar on the nacelle interface bracket through screws.

[0009] In some of these embodiments, after the installation of the laser clearance radar is completed, wire the laser clearance radar, power it on, and install the communication module.

[0010] In some of these embodiments, after the installation of the communication module is completed, conduct a communication check. If the communication between the laser clearance radar and the main control is normal, the green indicator light of the communication module is always on; if the communication between the laser clearance radar and the main control is abnormal, the red indicator light of the communication module is always on.

[0011] In some of these embodiments, after the communication check is correct, conduct an HMI calibration. Through the electronic terminal, if the ranging values of the three beams are similar and the values are constantly fluctuating slightly, the radar is successfully installed.

[0012] In some of these embodiments, the laser clearance radar calibration assistant and the inclinometer are used to accurately adjust the pitch angle and roll angle of the laser clearance radar.

[0013] In some of these embodiments, the detection end of the laser clearance radar is flush with the end of the tower barrel surface closest to the wind turbine blade.

[0014] In some of these embodiments, the installation position of the laser clearance radar is on one side of the tower barrel near the end of the wind turbine blade.

[0015] In some of these embodiments, it further includes: The regulating mechanism is installed in the input bin and is used to adjust the moving posture of the securities in the input bin.

[0016] The beneficial effects of the present invention are as follows: a method for detecting the clearance distance of a fan blade of the present invention is to install a laser clearance radar at the bottom of the nacelle cover, and to connect, energize and install a communication module for the laser clearance radar. After the installation is completed, the laser clearance radar is inspected and put into use after the inspection is completed. When in use, the transmitting end of the laser clearance radar emits a light pulse in the direction of the blade. After the light pulse encounters the fan blade, a return light pulse is formed. The light pulse is received, amplified and sent to the optical receiving module by the receiving lens. The internal timer calculates the distance between the laser clearance radar and the blade by recording the time difference between the emission and reception of the light pulse, according to the principle of constant light speed. The main control obtains the data of the distance between the laser clearance radar and the blade measured by multiple ranging modules, and after analysis by the processing algorithm, sends it to the fan main control, actively judges the data, if the distance between the radar and the blade is less than the set safety distance, the main control controls the fan to stop rotating and alarms, if the distance between the radar and the blade is greater than the set safety distance, the fan continues to run, the laser clearance radar continues to detect, and feedbacks the distance between the laser clearance radar and the blade. Furthermore, the present invention can monitor the clearance distance of the running blades and feedback the monitoring information in real time. If the distance between the laser clearance radar and the blades is less than the set safety value, the main control can promptly control the fan to stop rotating, thus avoiding the occurrence of tower sweeping accidents. DETAILED DESCRIPTION

[0017] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0018] As described in the background technology, the prior art often adopts increasing the distance between the blade and the tower or using flexible blades to avoid tower sweep accidents. However, no matter which method is used, it is impossible to monitor the running blades in real time and feedback information to avoid tower sweep accidents. The installation position of traditional radars is often determined by experience, and the accuracy is difficult to guarantee. Therefore, how to monitor the clearance distance of the running blades and feedback the monitoring information to avoid tower sweep accidents has become a technical problem that needs to be solved urgently by technicians in this field.

[0019] In order to solve the above problems, the present invention provides a method for detecting the clearance distance of fan blades, comprising the following steps: S1. Install a laser clearance radar at the bottom of the cabin cover; S2. The transmitting end of the laser clearance radar emits light pulses in the direction of the blade. After the light pulses encounter the fan blade, reflected light pulses are formed, which are received, amplified by the receiving lens and sent to the optical receiving module. The internal timer calculates the distance between the laser clearance radar and the blade based on the principle of the constancy of the speed of light by recording the time difference between the emission and reception of the light pulses. S3. The main controller obtains the data of the distances between the laser clearance radar and the blade measured by multiple ranging modules. After being analyzed by the processing algorithm, it is sent to the main controller of the fan. S4. When the distance between the laser clearance radar and the blade is less than the set safety distance, the main controller controls the fan to stop rotating and alarms. When the distance between the laser clearance radar and the blade is greater than the set safety distance, the fan continues to operate. The laser clearance radar continuously conducts detections and feeds back the distance between the laser clearance radar and the blade.

[0020] Preferably, the detection end of the laser clearance radar is flush with the lowest point of the rotation of the blade tip.

[0021] Preferably, the laser clearance radar consists of three single-line ranging modules to form a three-line laser ranging radar.

[0022] Specifically, during operation, the transmitting lens at the transmitting end of the laser clearance radar emits the light pulses generated by the light pulse generator. After the light pulses encounter the fan blade, reflected light pulses are formed, which are received and amplified by the receiving lens. The internal timer calculates the distance between the laser clearance radar and the blade based on the principle of the constancy of the speed of light by recording the time difference (TDC technology) between the emission and reception of the light pulses. The main controller obtains the data of the three ranging modules. After being analyzed by the processing algorithm, it is sent to the main controller of the fan through the canopen fieldbus to realize the real-time monitoring of the clearance distance of the blade.

[0023] Preferably, the installation of the laser clearance radar includes the following steps: S11. Taking the center of the tower barrel as the origin, the Y-axis as the direction of the generator main shaft, the X-axis passing through the center of the tower barrel and perpendicular to the Y-axis, and (x, y) as the horizontal installation position of the laser clearance radar, determine the installation position of the laser clearance radar through the laser clearance radar calibration assistant and the inclinometer. S12. Place the nacelle interface bracket at the determined installation position of the laser clearance radar on the nacelle cover, mark the opening position, and then draw a line. S13. Drill holes near the center of the marked area, then thread the anti-fall rope through and fix it. Then drill holes at the four corners of the marked area, cut according to the marked line, and remove the plate. S14. Place the nacelle interface bracket at the corresponding position of the nacelle opening and install it. Install the laser clearance radar on the nacelle interface bracket with screws.

[0024] Specifically, for the selection of the installation location, according to the specifications, the left front side at the bottom of the nacelle cover is determined as the installation point, that is, the side close to the blade, and the x and y values from the installation point to the tower center are accurately measured to ensure the accuracy of the measurement angle and range of the laser clearance radar. The attitude of the clearance radar is finely adjusted using an inclinometer and calibration assistant software to control the measurement accuracy within a very small error range.

[0025] Furthermore, based on the calibration parameters of the unit and the installation location data, the pitch angle of the laser clearance radar is accurately calculated to reduce manual calculation errors and improve the commissioning accuracy. An inclinometer is used to quickly and accurately adjust the attitude of the laser clearance radar to ensure the measurement accuracy of the laser clearance radar.

[0026] Furthermore, the method for measuring the x value is to measure from the center position of the laser clearance radar opening to the nacelle joint, and the method for measuring the y value is to measure from the center of the laser clearance radar opening to the position 90 degrees to the joint to the tower wall.

[0027] For drilling holes at the four corners within the marked range, it is to prevent cutting beyond the range and facilitate cutting and removal of the corners.

[0028] Preferably, after the installation of the laser clearance radar is completed, the wiring, power-on, and installation of the communication module of the laser clearance radar are carried out.

[0029] Specifically, when installing the laser clearance radar, pay attention that the arrow mark of "main shaft direction" points forward to the wind turbine side. Connect the 24VDC power line, network cable, and CAN cable to the laser clearance radar. The system light flashes under normal power supply, and the comm light stays on after the unit status is updated.

[0030] Preferably, after the installation of the communication module is completed, a communication check is carried out. If the communication between the laser clearance radar and the main control is normal, the green indicator light of the communication module stays on; if the communication between the laser clearance radar and the main control is abnormal, the red indicator light of the communication module stays on.

[0031] Specifically, add a Can communication module EL6751 at the back of the Beckhoff module group in the nacelle cabinet, install a small circuit breaker F86.3 near the X-OUT-1 terminal in the nacelle cabinet for disconnecting the 24VDC power supply of the laser clearance radar; install a Can channel lightning arrester and a 24V signal lightning arrester at the blank position on the lower layer guide rail of the nacelle cabinet.

[0032] Preferably, after the communication check is correct, the HMI calibration is carried out. Through the electronic terminal, if the three-beam ranging values are similar and the values are constantly fluctuating slightly, the radar is successfully installed.

[0033] Preferably, the laser clearance radar calibration assistant and the inclinometer are used to accurately adjust the pitch angle and roll angle of the laser clearance radar.

[0034] Preferably, the detection end of the laser clearance radar is flush with the end of the tower barrel surface closest to the wind turbine blade.

[0035] Preferably, the installation position of the laser clearance radar is on one side of the tower barrel near the end close to the wind turbine blade.

[0036] Through precise installation position positioning and fine radar attitude adjustment, the present invention ensures that the laser clearance radar can accurately measure the clearance distance between the blade and the tower barrel. In terms of the selection of the installation position, it is strictly determined to be on the left front side at the bottom of the nacelle cover, close to the impeller side and the generator main shaft, and the x and y values from the center of the tower barrel are accurately measured, laying a foundation for accurate measurement. By using an inclinometer and calibration assistant software, the pitch angle and roll angle of the radar are accurately adjusted to reduce the measurement error. In practical applications, it can monitor the clearance distance in real time and accurately, effectively avoid the collision accident between the blade and the tower barrel, and ensure the safe operation of the wind turbine. The present invention is more stable and reliable for monitoring the clearance distance from the tower barrel to the blade tip, can monitor the clearance distance in real time and accurately, effectively avoid the collision accident between the blade and the tower barrel, ensure the safe operation of the wind turbine, and greatly reduce the maintenance risk.

[0037] In the description of the present invention, it should be understood that the orientation or positional relationships indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be understood as a limitation of the present invention.

[0038] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In the description of the present invention, the meaning of "a plurality" is at least two, such as two, three, etc., unless otherwise specifically and clearly defined.

[0039] In the present invention, unless otherwise clearly specified and limited, the terms "install", "connect", "couple", "fix", etc. should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection, an electrical connection, or communicable with each other; it can be directly connected, or indirectly connected through an intermediate medium, and can be the internal communication of two elements or the interaction relationship between two elements, unless otherwise clearly limited. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0040] In the present invention, terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0041] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

Claims

1. A method for detecting the clearance distance of fan blades, characterized in that: The following steps are involved: S1. Install a laser clearance radar at the bottom of the cabin cover; S2. The transmitting end of the laser clearance radar emits a light pulse in the direction of the blade. When the light pulse encounters the wind turbine blade, it forms a return light pulse, which is received and amplified by the receiving lens and sent to the optical receiving module. The internal timer records the time difference between the emission and reception of the light pulse and calculates the distance between the laser clearance radar and the blade based on the principle of constant light speed. S3, the main control obtains the data of the distance between the laser clearance radar and the blades measured by multiple ranging modules, and sends it to the wind turbine main control after processing and algorithm analysis; S4: If the distance between the laser clearance radar and the blade is less than the set safety distance, the main control stops the fan and issues an alarm. If the distance between the laser clearance radar and the blade is greater than the set safety distance, the fan continues to run, the laser clearance radar continues to detect, and feeds back the distance between the laser clearance radar and the blade.

2. A method for detecting the clearance distance of a fan blade according to claim 1, characterized in that: The laser clearance radar detection end is flush with the bottom end of the blade tip rotation.

3. A method for detecting the clearance distance of a fan blade according to claim 1, characterized in that: The laser clearance radar is composed of three single-line ranging modules to form a three-line laser ranging radar.

4. A method for detecting the clearance distance of a fan blade according to claim 1, characterized in that: Installing the LiDAR includes the following steps: S11. Take the center of the tower as the origin, the Y axis as the main axis direction of the generator, the X axis passes through the center of the tower and is perpendicular to the Y axis, (x, y) is the horizontal installation position of the laser clearance radar, and determine the installation position of the laser clearance radar through the laser clearance radar calibration assistant and the inclinometer; S12. Place the cabin interface bracket at the installation position of the laser clearance radar determined on the cabin cover, mark the opening position, and then draw lines; S13. Drill a hole near the center of the marked area, insert the anti-fall rope and secure it, then drill holes at the four corners of the marked area, cut according to the marked lines, and remove the plate; S14. Place the cabin interface bracket at the corresponding position of the cabin opening and install it, and install the laser clearance radar on the cabin interface bracket by screws.

5. A method for detecting the clearance distance of fan blades according to claim 4, characterized in that: After the laser clearance radar is installed, the laser clearance radar is wired, powered on, and the communication module is installed.

6. A method for detecting the clearance distance of fan blades according to claim 5, characterized in that: After the communication module is installed, perform a communication check. If the communication between the laser clearance radar and the main control is normal, the green indicator light of the communication module will be on. If the communication between the laser clearance radar and the main control is abnormal, the red indicator light of the communication module will be on.

7. A method for detecting the clearance distance of fan blades according to claim 6, characterized in that: After the communication check is correct, the HMI calibration is carried out. If the three-beam ranging values ​​are similar through the electronic terminal and the values ​​are constantly fluctuating slightly, the radar installation is successful.

8. A method for detecting the clearance distance of fan blades according to claim 4, characterized in that: The laser clearance radar calibration assistant and the inclinometer are used to accurately adjust the pitch angle and roll angle of the laser clearance radar.

9. A method for detecting the clearance distance of wind turbine blades according to claim 1, characterized in that: The detection end of the laser clearance radar is flush with the end of the tower surface closest to the wind turbine blades.

10. A method for detecting the clearance distance of wind turbine blades according to claim 1, characterized in that: The laser clearance radar is installed on one side of the tower close to one end of the wind turbine blades.