Wind turbine generator blade root bolt fracture monitoring system and method

Abstract

The invention discloses a wind turbine generator blade root bolt fracture monitoring system and method, and relates to the technical field of wind power generation, a wire holder is mounted at an exposed thread on a target blade root bolt in each fan blade, and a fixing seat is mounted at the exposed thread on each blade root bolt except the target blade root bolt; the wire holder is connected with a first wire and a second wire, the first conductive cable is sequentially connected with all the fixing seats in series, the first end and the second end of the first conductive cable are connected with the first wire and the second wire through the wire holder respectively, and the first wire and the second wire are connected with the input end and the output end of the monitoring circuit respectively. Therefore, the monitoring circuit and the first conductive cable form a power-on loop. The first conductive cable can be broken when the blade root bolt is broken, the monitoring circuit can monitor the bolt breakage condition in real time by monitoring the on-off condition of the first conductive cable, the blade root bolt breakage condition can be found in time, manual inspection is not needed, missing detection or false detection caused by subjective factors is avoided, and the labor cost is reduced.

Description

Technical Field

[0001] The present application relates to the technical field of wind power generation, and in particular to a system and method for monitoring the fracture of blade root bolts of a wind turbine. Background Art

[0002] In the field of wind power generation, wind turbines are core equipment, and blades are an important part of wind turbines. The stability and safety of blades directly affect the normal operation of wind turbines. The blade root bolts are key components that connect blades to hubs, and their breakage is an important safety hazard. Once the blade root bolts break, the blades may become loose or even fall off, which will not only damage the wind power generation equipment, but also pose a serious threat to ground personnel and facilities. Therefore, timely monitoring of the breakage of blade root bolts and taking corresponding measures are of great significance to ensure the stable operation of wind turbines and the safety of personnel.

[0003] At present, the monitoring of blade root bolts is mainly carried out through manual regular inspections. Although manual regular inspections can detect the breakage of blade root bolts, they require frequent manual labor, are labor-intensive, and inefficient, and cannot achieve all-weather real-time monitoring. Moreover, the method of manual regular inspections is affected by subjective factors and is prone to missed inspections or false inspections. In addition, manual inspections also have safety risks, especially in severe weather conditions, when manual inspections may be restricted and problems cannot be discovered in a timely manner.

[0004] Therefore, how to achieve real-time monitoring and timely detect the fracture of blade root bolts, how to avoid missed detection or false detection due to subjective factors, and how to reduce labor costs are problems that technical personnel in this field need to solve. Summary of the invention

[0005] The purpose of this application is to provide a wind turbine blade root bolt fracture monitoring system and method, which is used to solve the following problems: manual periodic inspections cannot detect blade root bolt fractures in time, manual periodic inspections are easily affected by subjective factors and may result in missed inspections or false inspections, and the labor cost of manual periodic inspections is high.

[0006] In order to solve the above technical problems, the present application provides a wind turbine blade root bolt fracture monitoring system, comprising: a wiring seat, a plurality of fixing seats, a first conductive cable, a first wire, a second wire and a monitoring circuit;

[0007] The terminal block is installed at the exposed thread on the target blade root bolt in each wind turbine blade, and the fixing block is installed at the exposed thread on each blade root bolt in the wind turbine blade except the target blade root bolt, the terminal block is respectively connected to the first wire and the second wire, the first conductive cable is connected in series with all the fixing blocks in sequence, and the first end of the first conductive cable is connected to the first wire via the terminal block, the second end of the first conductive cable is connected to the second wire via the terminal block, the first wire is connected to the input end of the monitoring circuit, and the second wire is connected to the output end of the monitoring circuit, so that the monitoring circuit and the first conductive cable form a power-on loop, the first conductive cable is used to be disconnected when the blade root bolt is broken, and the monitoring circuit is used to monitor the on-off status of the first conductive cable in real time.

[0008] In a feasible embodiment, the first conductive cable is made of copper foil, the terminal block is a push-type terminal block, the fixing base is provided with a first through hole, the first connection end of the push-type terminal block is connected to the first wire, the second connection end of the push-type terminal block is connected to the second wire, the first end of the copper foil is connected to the third connection end of the push-type terminal block, the second end of the copper foil passes through the first through hole of each of the fixing bases in turn and is connected to the fourth connection end of the push-type terminal block, the first connection end is electrically connected to the third connection end, and the second connection end is electrically connected to the fourth connection end.

[0009] In a feasible embodiment, the first conductive cable includes a first sub-conductive cable, a second sub-conductive cable and a plurality of third sub-conductive cables, the terminal block is a first push-type terminal block, the fixed seat is a second push-type terminal block, the first terminal end of the first push-type terminal block is press-connected to the first end of the first sub-conductive cable and the first conductive wire, the second terminal end of the first push-type terminal block is press-connected to the first end of the second sub-conductive cable and the second conductive wire, the second end of the first sub-conductive cable is press-connected to a second push-type terminal block adjacent to the first push-type terminal block, the second end of the second sub-conductive cable is press-connected to another second push-type terminal block adjacent to the first push-type terminal block, and the two ends of the third sub-conductive cable are respectively press-connected to two adjacent second push-type terminal blocks.

[0010] In a feasible embodiment, the device further comprises a second conductive cable, wherein the second conductive cable comprises a fourth sub-conductive cable, a fifth sub-conductive cable and a plurality of sixth sub-conductive cables, wherein the third terminal of the first push-type wiring seat is firmly connected to the first end of the fourth sub-conductive cable, the fourth terminal of the first push-type wiring seat is firmly connected to the first end of the fifth sub-conductive cable, the second end of the fourth sub-conductive cable is firmly connected to a second push-type wiring seat adjacent to the first push-type wiring seat, the second end of the fifth sub-conductive cable is firmly connected to another second push-type wiring seat adjacent to the first push-type wiring seat, and the two ends of the sixth sub-conductive cable are firmly connected to two adjacent second push-type wiring seats, respectively, the first terminal is electrically connected to the third terminal, the second terminal is electrically connected to the fourth terminal, a conductor is arranged in the second push-type wiring seat, the second push-type wiring seat is used to connect the two terminals of the first conductive cable to be electrically connected to the two ends of the conductor respectively, and the second push-type wiring seat is used to connect the two terminals of the second conductive cable to be electrically connected to the two ends of the conductor respectively, so that the second conductive cable and the first conductive cable are connected in parallel.

[0011] In a feasible embodiment, it also includes an insulating coil, and the insulating coil is used to connect the wiring seat and all the fixing seats in series.

[0012] In a feasible embodiment, the surface of the terminal seat that fits with the target blade root bolt is provided with a thread that matches the target blade root bolt, the surface of the fixing seat that fits with the blade root bolt is provided with a thread that matches the blade root bolt, and the terminal seat is tied to the target blade root bolt through a rubber ring or a cable tie, and the fixing seat is tied to the blade root bolt through a rubber ring or a cable tie.

[0013] In a feasible embodiment, the edge of the copper foil is provided with notches at intervals, and the thickness of the copper foil is 0.05-0.1 mm.

[0014] The present application also provides a method for monitoring the fracture of a blade root bolt of a wind turbine, which is applied to the above-mentioned monitoring system for the fracture of a blade root bolt of a wind turbine, comprising:

[0015] Acquire the on / off status of the first conductive cable in real time;

[0016] If the on-off condition is detected as a passage, the blade root bolt is not broken;

[0017] If the on-off condition is detected as an open circuit, the blade root bolt is broken.

[0018] In a feasible embodiment, a noise detection device is installed in the fan blade and near the blade root bolt, and further includes:

[0019] Acquiring the noise signal detected by the noise detection device in real time;

[0020] Preprocessing the noise signal, and extracting features from the preprocessed noise signal to obtain feature parameters;

[0021] Whether the blade root bolt is broken is determined according to the characteristic parameters.

[0022] In a feasible embodiment, determining whether the blade root bolt is broken according to the characteristic parameter includes:

[0023] Normalizing each of the characteristic parameters;

[0024] Combining multiple normalized feature parameters into a feature vector;

[0025] The feature vector is input into a preset machine learning model, and whether the blade root bolt is broken is determined according to an output result of the preset machine learning model.

[0026] The present application provides a wind turbine blade root bolt fracture monitoring system, comprising: a terminal block, a plurality of fixing blocks, a first conductive cable, a first wire, a second wire and a monitoring circuit; the terminal block is installed at the exposed thread on the target blade root bolt in each wind turbine blade, and the exposed thread on each blade root bolt other than the target blade root bolt in the wind turbine blade is installed with a fixing block, the terminal block is respectively connected to the first wire and the second wire, the first conductive cable is sequentially connected in series to all the fixing blocks, and the first end of the first conductive cable is connected to the first wire via the terminal block, the second end of the first conductive cable is connected to the second wire via the terminal block, the first wire is connected to the input end of the monitoring circuit, and the second wire is connected to the output end of the monitoring circuit, so that the monitoring circuit and the first conductive cable form a power-on loop, the first conductive cable is used to be disconnected when the blade root bolt is broken, and the monitoring circuit is used to monitor the on-off status of the first conductive cable in real time. A first conductive cable is used to connect all the blade root bolts in the blade in series and form an energized circuit with the monitoring circuit. The monitoring circuit can monitor the fracture of the blade root bolts in real time by monitoring the on-off status of the first conductive cable. No manual inspection is required, and the fracture of the blade root bolts can be discovered in time to avoid missed detection or false detection due to subjective factors. At the same time, labor costs are reduced and work efficiency is greatly improved.

[0027] The beneficial effects of the wind turbine blade root bolt fracture monitoring method provided in the present application correspond to the system, and the effects are as above. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0029] Figure 1 A structural diagram of a first wind turbine blade root bolt fracture monitoring system provided in an embodiment of the present application;

[0030] Figure 2 A schematic diagram of the blade root of a wind turbine blade of a wind turbine provided in an embodiment of the present application;

[0031] Figure 3 A schematic diagram of a series circuit formed by a first conductive cable and a monitoring circuit in three blades provided in an embodiment of the present application;

[0032] Figure 4 A partial schematic diagram of a first wind turbine blade root bolt fracture monitoring system provided in an embodiment of the present application;

[0033] Figure 5 A structural diagram of a second wind turbine blade root bolt fracture monitoring system provided in an embodiment of the present application;

[0034] Figure 6 A structural diagram of a third wind turbine blade root bolt fracture monitoring system provided in an embodiment of the present application;

[0035] Figure 7 A schematic diagram of the connection between a first conductive cable, a second conductive cable, a first wire, and a second wire provided in an embodiment of the present application;

[0036] Figure 8 A schematic diagram of partial connection between a first conductive cable, a second conductive cable, a first conductive wire, and a second conductive wire provided in an embodiment of the present application;

[0037] Fig. 9 A structural diagram of a fourth wind turbine blade root bolt fracture monitoring system provided in an embodiment of the present application;

[0038] Fig.10 A flow chart of a method for monitoring the fracture of blade root bolts of a wind turbine set provided in an embodiment of the present application.

[0039] The reference numerals are as follows: 1-terminal block, 2-fixed seat, 3-first conductive cable, 301-first sub-conductive cable, 302-second sub-conductive cable, 303-third sub-conductive cable, 4-first conductor, 5-second conductor, 6-monitoring circuit, 7-blade root bolt, 8-blade root nut, 9-rubber ring, 10-main engine hub, 11-automatic pitch system terminal, 12-power supply control switch, 13-electric slip ring channel, 14-cabin terminal block, 15-cabin cabinet, 16-second conductive cable, 1601-fourth sub-conductive cable, 1602-fifth sub-conductive cable, 1603-sixth sub-conductive cable, 17-A terminal, 18-B terminal, 19-C terminal, 20-D terminal, 21-E terminal, 22-F terminal, 23-G terminal, 24-H terminal, 25-conductor, 26-insulating coil. DETAILED DESCRIPTION

[0040] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0041] The core of this application is to provide a wind turbine blade root bolt fracture monitoring system and method, which are used to achieve real-time monitoring and timely detection of blade root bolt fractures, how to avoid missed detection or false detection due to subjective factors, and how to reduce labor costs.

[0042] In order to enable those skilled in the art to better understand the present application, the present application is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0043] Figure 1 The structural diagram of the first wind turbine blade root bolt fracture monitoring system provided in the embodiment of the present application is as follows: Figure 1As shown, the wind turbine blade root bolt fracture monitoring system includes: a terminal block 1, a plurality of fixing blocks 2, a first conductive cable 3, a first wire 4, a second wire 5 and a monitoring circuit 6; the terminal block 1 is installed at the exposed thread on the target blade root bolt in each wind turbine blade, and the exposed thread on each blade root bolt 7 of the wind turbine blade except the target blade root bolt is installed with a fixing block 2, the terminal block 1 is respectively connected to the first wire 4 and the second wire 5, the first conductive cable 3 is sequentially connected in series with all the fixing blocks 2, and the first end of the first conductive cable 3 is connected to the first wire 4 via the terminal block 1, the second end of the first conductive cable 3 is connected to the second wire 5 via the terminal block 1, the first wire 4 is connected to the input end of the monitoring circuit 6, and the second wire 5 is connected to the output end of the monitoring circuit 6, so that the monitoring circuit 6 and the first conductive cable 3 form a power-on loop, the first conductive cable 3 is used to be disconnected when the blade root bolt 7 is broken, and the monitoring circuit 6 is used to monitor the on-off status of the first conductive cable 3 in real time.

[0044] To facilitate understanding of the present application, the position of the blade root bolt 7 is briefly introduced below. Figure 2 A schematic diagram of the blade root of a wind turbine blade provided in an embodiment of the present application is shown in FIG. Figure 2 As shown, the blade root bolt 7 is the main connection part between the blade and the main engine hub 10, and its force conditions are complex, including aerodynamic load, gravity load and centrifugal load. A plurality of blade root bolts 7 are evenly distributed along the blade root pitch circle on the blade root end surface, and one end of the blade root bolt 7 with threads extends out of the blade end surface and is connected to the main engine hub 10 in conjunction with the blade root nut 8. The exposed threads on the blade root bolt 7 refer to the part of the blade root bolt 7 that extends out of the blade end surface.

[0045] The terminal block 1 in the embodiment of the present application is installed at the exposed thread on any target blade root bolt in the wind turbine blade, and the fixing seat 2 is installed at the exposed thread on the blade root bolt 7 other than the target blade root bolt. The embodiment of the present application does not limit the specific method of installing the fixing seat 2 and the terminal block on the blade root bolt, and can adopt a magnetic attraction method, a welding method, or a binding method, etc.; Specifically, the surface of the terminal block 1 that fits the target blade root bolt is provided with a thread that matches the target blade root bolt, and the surface of the fixing seat 2 that fits the blade root bolt 7 is provided with a thread that matches the blade root bolt 7, and the terminal block is tied to the target blade root bolt through a rubber ring 9 or a cable tie, and the fixing seat 2 is tied to the blade root bolt 7 through a rubber ring 9 or a cable tie. By providing threads that match the blade root bolt on the surface of the terminal block 1 and the surface of the fixing seat 2, the contact area between the terminal block 1 and the target blade root bolt and between the fixing seat 2 and the blade root bolt 7 can be increased, so that the terminal block 1 and the fixing seat 2 can be stably attached to the blade root bolt under the action of the rubber ring 9 or the cable tie. Furthermore, the detachable installation is performed by using the rubber ring 9 or the cable tie, which also facilitates the disassembly and assembly of the wiring base 1 and the fixing base 2 when the blade root bolt 7 is maintained.

[0046] In the embodiment of the present application, when the blade root bolt 7 breaks, the first conductive cable 3 can be disconnected under the shaking of gravity and rotational acceleration. The blade root bolt 7 mentioned in the present application also includes the target blade root bolt breaking. The embodiment of the present application does not specifically limit the method by which the first conductive cable 3 can be disconnected when the blade root bolt 7 breaks. The monitoring circuit 6 forms an energized circuit with the first conductive cable 3. When the first conductive cable 3 is disconnected, the monitoring circuit 6 produces a low-level signal. When the first conductive cable 3 is not disconnected, the monitoring circuit 6 produces a high-level signal; the monitoring circuit 6 can be connected to the main control system through a data acquisition device, and the main control system alarms when the blade root bolt 7 breaks, and presents the alarm in the form of an event log. Of course, the monitoring circuit 6 can also be connected to a terminal (mobile phone or computer, etc.) through a data acquisition device. By remotely obtaining information on whether the blade root bolt 7 is broken and falling off, the staff can monitor the status of the blade root bolt 7 in real time while being away from the wind turbine, thereby improving work efficiency and safety.

[0047] Usually, a wind turbine includes three blades. The monitoring circuit 6 of each blade and its first conductive cable 3 may form an energized circuit, and each monitoring circuit 6 is responsible for monitoring the fracture of a blade root bolt 7 in a blade. Alternatively, the first wire 4 in the first blade may be connected to the input end of the monitoring circuit 6, the second wire 5 in the first blade may be connected to the first wire 4 in the second blade, the second wire 5 in the second blade may be connected to the first wire 4 in the third blade, and the second wire 5 in the third blade may be connected to the output end of the monitoring circuit 6, so that the monitoring circuit 6 and the three first conductive cables 3 in the three blades form an energized circuit together. When the monitoring circuit 6 detects a circuit break, the staff may check each blade root bolt 7 in the three blades one by one. Figure 3 A schematic diagram of a series circuit formed by a first conductive cable and a monitoring circuit in three blades provided in an embodiment of the present application, such as Figure 3 As shown, the entire monitoring circuit 6 includes the self-pitch system terminal 11 in the wind turbine, the power supply control switch 12 and the input / output module (WP-Line 351 module) in the cabin cabinet 15; the cable of the monitoring circuit 6 is connected to the self-pitch system terminal 11, and then connected in sequence to the spare signal cable in the electric slip ring channel 13 and the cabin terminal block 14 and the input / output module in the cabin cabinet 15. The self-pitch system terminal 11 is used to connect the power supply of the pitch motor to power the monitoring circuit 6. The WP-Line 351 module is mainly responsible for the input and output of signals, as well as signal processing and communication capabilities, etc., which can meet the needs of various signal processing in the wind turbine control system. In addition, the monitoring circuit 6 can also include an air switch, which itself has the function of monitoring current and voltage changes, and can automatically cut off the circuit when the current exceeds the set value, and is used to monitor the power circuit status in real time and provide protection functions.

[0048] A wind turbine blade root bolt fracture monitoring system provided in an embodiment of the present application comprises: a terminal block 1, a plurality of fixing blocks 2, a first conductive cable 3, a first wire 4, a second wire 5 and a monitoring circuit 6; the terminal block 1 is installed at the exposed thread on the target blade root bolt 7 in each wind turbine blade, and the exposed thread on each blade root bolt 7 except the target blade root bolt 7 in the wind turbine blade is installed with a fixing block 2, the terminal block 1 is respectively connected to the first wire 4 and the second wire 5, the first conductive cable 3 is sequentially connected in series with all the fixing blocks 2, and the first end of the first conductive cable 3 is connected to the first wire 4 via the terminal block 1, the second end of the first conductive cable 3 is connected to the second wire 5 via the terminal block 1, the first wire 4 is connected to the input end of the monitoring circuit 6, and the second wire 5 is connected to the output end of the monitoring circuit 6, so that the monitoring circuit 6 and the first conductive cable 3 form a power-on loop, the first conductive cable 3 is used to be disconnected when the blade root bolt 7 is broken, and the monitoring circuit 6 is used to monitor the on-off status of the first conductive cable 3 in real time. All the blade root bolts 7 in the blade are connected in series by the first conductive cable 3 and form an energized circuit with the monitoring circuit 6. The monitoring circuit 6 can monitor the fracture of the blade root bolt 7 in real time by monitoring the on-off status of the first conductive cable 3. No manual inspection is required, and the fracture of the blade root bolt 7 can be discovered in time to avoid missed detection or false detection due to subjective factors. At the same time, labor costs are reduced and work efficiency is greatly improved.

[0049] Based on the above embodiments, the embodiment of the present application provides a method for disconnecting the first conductive cable 3 when the blade root bolt 7 is broken. Figure 4 A partial schematic diagram of a first wind turbine blade root bolt fracture monitoring system provided in an embodiment of the present application, as shown in FIG. Figure 1 and Figure 4 As shown, it specifically includes: the first conductive cable 3 is made of copper foil, the terminal block 1 is a push-type terminal block, the fixing base 2 is provided with a first through hole, the first connection end of the push-type terminal block is connected to the first wire 4, the second connection end of the push-type terminal block is connected to the second wire 5, the first end of the copper foil is connected to the third connection end of the push-type terminal block, the second end of the copper foil sequentially passes through the first through hole of each fixing base 2 and is connected to the fourth connection end of the push-type terminal block, the first connection end is electrically connected to the third connection end, and the second connection end is electrically connected to the fourth connection end. Among them, the copper foil is a copper foil with an insulating layer.

[0050] When the blade root bolt 7 breaks, the relatively thin copper foil can break due to shaking under the action of gravity and rotational acceleration. In order to further ensure that the copper foil can break when the blade root bolt 7 breaks, notches can be provided at intervals on the edges of the copper foil, and the thickness of the copper foil is 0.05-0.1mm, ensuring that at least one notch is provided on the copper foil between two adjacent fixing seats 2. The terminal block 1 adopts a push-type terminal block, and the first wire 4 and the second wire 5 are respectively press-connected to the first connection end and the second connection end of the push-type terminal block. The specific operation steps are: use wire strippers to peel off a certain length of the outer skin of the first wire 4 to expose the internal wire; insert the stripped first wire 4 into the jack of the first connection end of the push-type terminal block, and press the pressing block or button on the push-type terminal block so that the metal spring clamps the wire to complete the connection. The connection operation of the second wire 5 and the push-type terminal block refers to the connection operation of the first wire 4. Figure 1 As shown, the first end of the copper foil is connected to the third connection end of the push-type wiring seat, and the second end of the copper foil passes through the first through hole of each fixing seat 2 in turn and is connected to the fourth connection end of the push-type wiring seat. Figure 1 Only part of the fixing base 2 is shown. The copper foil and the monitoring circuit 6 form an electrical circuit. When the blade root bolt 7 breaks and causes the copper foil to disconnect, the monitoring circuit 6 detects that the on-off condition is an open circuit. Among them, the push-type terminal block (also called push-type terminal block, spring terminal block or quick terminal block) is a type of terminal block used for electronic equipment and electrical connections. It provides elastic clamping force through the internal metal spring sheet to fix the wire in the wiring hole without using a screwdriver or nut, thereby achieving quick and convenient connection.

[0051] Based on the above embodiment, the embodiment of the present application provides another implementation method of disconnecting the first conductive cable 3 when the blade root bolt 7 is broken. Figure 5 The structural diagram of the second wind turbine blade root bolt fracture monitoring system provided in the embodiment of the present application is as follows: Figure 5 As shown, the first conductive cable 3 includes a first sub-conductive cable 301, a second sub-conductive cable 302 and a plurality of third sub-conductive cables 303, the terminal block 1 is a first push-type terminal block, the fixing base 2 is a second push-type terminal block, the first terminal end of the first push-type terminal block is press-connected to the first end of the first sub-conductive cable 301 and the first wire 4, the second terminal end of the first push-type terminal block is press-connected to the first end of the second sub-conductive cable 302 and the second wire 5, the second end of the first sub-conductive cable 301 is press-connected to the second push-type terminal block adjacent to the first push-type terminal block, the second end of the second sub-conductive cable 302 is press-connected to another second push-type terminal block adjacent to the first push-type terminal block, and the two ends of the third sub-conductive cable 303 are respectively press-connected to two adjacent second push-type terminal blocks.

[0052] The operation of the press connection between the sub-conductive cable and the push-type terminal block in the embodiment itself specifically refers to the connection operation between the first conductor 4 and the push-type terminal block in the previous embodiment, and will not be repeated here. In order to ensure that the first conductive cable 3 can be disconnected when the blade root bolt 7 breaks as much as possible, the first conductive cable 3 is composed of multiple sub-conductive cables, so that when the bolt breaks, the shaking caused by gravity and rotational acceleration can cause the end of the sub-conductive cable to be detached from the push-type terminal block. Further, the length of the end of the sub-conductive cable inserted into the terminal jack of the push-type terminal block can be reduced to avoid the press connection being too firm. The first sub-conductive cable 301, the second sub-conductive cable 302 and the plurality of third sub-conductive cables 303 form an energized circuit with the monitoring circuit 6. When the end of any sub-conductive cable is detached from the push-type terminal block, the monitoring circuit 6 detects that the on-off condition is a circuit breaker, indicating that the blade root bolt 7 is broken.

[0053] Based on the above embodiments, Figure 6 The structural diagram of the third wind turbine blade root bolt fracture monitoring system provided in the embodiment of the present application is as follows: Figure 6 As shown, the second conductive cable 16 is also included, and the second conductive cable 16 includes a fourth sub-conductive cable 1601, a fifth sub-conductive cable 1602 and a plurality of sixth sub-conductive cables 1603. The third terminal of the first push-type wiring seat is firmly connected to the first end of the fourth sub-conductive cable 1601, the fourth terminal of the first push-type wiring seat is firmly connected to the first end of the fifth sub-conductive cable 1602, the second end of the fourth sub-conductive cable 1601 is firmly connected to the second push-type wiring seat adjacent to the first push-type wiring seat, and the second end of the fifth sub-conductive cable 1602 is firmly connected to the other second push-type wiring seat adjacent to the first push-type wiring seat. A second push-type terminal block is provided, and both ends of the sixth sub-conductive cable 1603 are respectively firmly connected to two adjacent second push-type terminal blocks, the first terminal is electrically connected to the third terminal, and the second terminal is electrically connected to the fourth terminal. A conductor 25 is provided in the second push-type terminal block, and the second push-type terminal block is used to connect the two terminals of the first conductive cable 3 to be electrically connected to the two ends of the conductor 25 respectively, and the second push-type terminal block is used to connect the two terminals of the second conductive cable 16 to be electrically connected to the two ends of the conductor 25 respectively, so that the second conductive cable 16 and the first conductive cable 3 between the two adjacent push-type terminal blocks are connected in parallel.

[0054] The embodiments of this application are Figure 5On the basis of the invention, a second conductive cable 16 is added, wherein the second conductive cable 16 can be thicker than the first conductive cable 3, and the two ends of each sub-conductive cable in the second conductive cable 16 are respectively firmly connected to the push-type terminal block. Specifically, the third terminal and the fourth terminal of the first push-type terminal block can be a jack structure, and the first end of the fourth sub-conductive cable 1601 and the first end of the fifth sub-conductive cable 1602 are inserted into the jack structure and compressed by screws. The terminal of the second push-type terminal block used to connect the second conductive cable 16 can also be a jack structure, and the end of the second conductive cable 16 is compressed by screws. Another firm connection can also be achieved by welding or twisting, or by a combination of welding and screw crimping. The function of the second conductive cable 16 is to be connected in parallel with the first conductive cable 3, and when the bolt breaks, the sub-conductive cables of the first conductive cable 3 can be detached from the push-type terminal block, while the sub-conductive cables of the second conductive coil are not easily detached from the push-type terminal block.

[0055] The monitoring system is Figure 6 How does the monitoring circuit 6 monitor the on-off status of the first conductive cable 3? For ease of understanding, the following is combined with Figure 7 and Figure 8 For further introduction, Figure 7 A schematic diagram of the connection between a first conductive cable, a second conductive cable, a first wire and a second wire provided in an embodiment of the present application, Figure 8 A partial connection diagram of a first conductive cable, a second conductive cable, a first wire, and a second wire provided in an embodiment of the present application. Figure 7 As shown, the first conductive cable 3 and the second conductive cable 16 are connected in parallel via a press-type terminal block. Figure 8As shown, for the convenience of introduction, the first terminal of the first push-type terminal block is recorded as A terminal 17, the second terminal of the first push-type terminal block is recorded as B terminal 18, the third terminal of the first push-type terminal block is recorded as C terminal 19, the fourth terminal of the first push-type terminal block is recorded as D terminal 20, and the four terminals of the second push-type are recorded as E terminal 21, F terminal 22, G terminal 23 and H terminal 24 respectively. The A terminal 17 is pressed to connect the first end of the first sub-conductive cable 301 and the first wire 4, the B terminal 18 is pressed to connect the first end and the second wire 5 of the second sub-conductive cable 302, the second end of the first sub-conductive cable 301 is pressed to connect to the E terminal 21 of a second push-type wiring seat adjacent to the first push-type wiring seat, the second end of the second sub-conductive cable 302 is pressed to connect to the E terminal 21 of another second push-type wiring seat adjacent to the first push-type wiring seat, and the two ends of the third sub-conductive cable 303 are respectively pressed to connect to the F terminal 22 of one of the two adjacent second push-type wiring seats and the E terminal 21 of the other second push-type wiring seat; the C terminal 19 is firmly connected to the first end of the fourth sub-conductive cable 1601, and the D terminal 20 is firmly connected to the fifth sub-conductive cable 303. The first end of the fourth sub-conductive cable 1601 is firmly connected to the G terminal 23 of a second push-type terminal block adjacent to the first push-type terminal block, the second end of the fifth sub-conductive cable 1602 is firmly connected to the G terminal 23 of another second push-type terminal block adjacent to the first push-type terminal block, and the two ends of the sixth sub-conductive cable 1603 are respectively pressed and connected to the H terminal 24 of one of the two adjacent second push-type terminal blocks and the G terminal 23 of the other second push-type terminal block; the A terminal 17 is electrically connected to the C terminal 19, the B terminal 18 is electrically connected to the D terminal 20, the E terminal 21 and the G terminal 23 are connected to the first end of the conductor 25, and the F terminal 22 and the H terminal 24 are connected to the second end of the conductor 25. Figure 8 , between two adjacent push-type wiring seats, there are a first conductive cable 3 and a second conductive cable 16 with a certain resistance value connected in parallel, and then connected in series to the first push-type wiring seat. When a bolt breaks, the first conductive cable 3 (the first sub-conductive cable 301, the second sub-conductive cable 302 or the third sub-conductive cable 303) is disconnected from the push-type wiring seat, and the monitoring circuit 6 detects that the resistance value becomes larger, but the second conductive cable 16 can remain powered on for continuous monitoring. When more blade root bolts 7 break, the resistance value monitored by the monitoring circuit 6 will increase as the number of blade root bolts 7 broken increases. Therefore, the on-off status of the first conductive cable 3 can be determined by the change in resistance value. The monitoring circuit 6 in the embodiment of the present application can continue to monitor whether there are new bolts broken after the blade root bolt 7 breaks, and the number of broken blade root bolts 7 can be estimated by the change in resistance value.

[0056] Based on the above embodiments, Figure 1 or Figure 5 On the basis of, the embodiment of the present application further includes an insulating coil 26, and the insulating coil 26 is used to connect the wiring seat 1 and all the fixing seats 2 in series. Specifically, Fig. 9 The structural diagram of the fourth wind turbine blade root bolt fracture monitoring system provided in the embodiment of the present application is as follows: Fig. 9 As shown, both the terminal block 1 and the fixing block 2 are provided with through holes, and the insulating coil 26 passes through the through holes of the terminal block 1 and all the fixing blocks 2 in sequence, connecting the terminal block 1 and all the fixing blocks 2 in series; wherein the insulating coil 26 can be a rubber coil with a certain expansion space. The insulating coil 26 prevents the blade root bolt 7 from breaking so that the fixing block 2 or the terminal block falls into the wind wheel and damages the unit components.

[0057] Fig.10 A flow chart of a method for monitoring the fracture of blade root bolts of a wind turbine provided in an embodiment of the present application is shown in FIG. Fig.10 As shown, the wind turbine blade root bolt fracture monitoring method is applied to the above-mentioned wind turbine blade root bolt fracture monitoring system, including:

[0058] S10: Acquire the on / off status of the first conductive cable in real time.

[0059] S11: If the on-off condition is detected as a passage, the blade root bolt is not broken.

[0060] S12: If the on-off condition is detected as an open circuit, the blade root bolt is broken.

[0061] If the blade root bolt fracture monitoring system is Figure 1 and Figure 5 The on-off condition of the first conductive cable is current or no current. If there is current in the entire power-on circuit, the on-off condition of the first conductive cable 3 is a circuit, and the monitoring circuit 6 generates a high-level signal; if there is no current in the entire power-on circuit, the on-off condition of the first conductive cable 3 is a circuit break, and the monitoring circuit 6 generates a low-level signal. The main control system obtains the low-level signal of the monitoring circuit 6 and generates an alarm message.

[0062] If the blade root bolt fracture monitoring system is Figure 6 The on-off condition of the first conductive cable 3 is a resistance value. If the resistance value is greater than the upper limit of the preset range, the on-off condition of the first conductive cable 3 is determined to be an open circuit, and the number of broken blade root bolts 7 is determined according to the change in the resistance value; if the resistance value is within the preset range, the on-off condition of the first conductive cable 3 is determined to be a pass. The monitoring circuit 6 can feed back the detected resistance value to the main control system.

[0063] A method for monitoring the fracture of a blade root bolt of a wind turbine provided in an embodiment of the present application is applied to the above-mentioned monitoring system for the fracture of a blade root bolt of a wind turbine, comprising: a terminal block 1, a plurality of fixing blocks 2, a first conductive cable 3, a first wire 4, a second wire 5 and a monitoring circuit 6; the terminal block 1 is installed at the exposed thread on the target blade root bolt 7 in each wind turbine blade, and the exposed thread on each blade root bolt 7 of the wind turbine blade except the target blade root bolt 7 is installed with a fixing block 2, the terminal block 1 is respectively connected to the first wire 4 and the second wire 5, the first conductive cable 3 is sequentially connected in series with all the fixing blocks 2, and the first end of the first conductive cable 3 is connected to the first wire 4 via the terminal block 1, the second end of the first conductive cable 3 is connected to the second wire 5 via the terminal block 1, the first wire 4 is connected to the input end of the monitoring circuit 6, and the second wire 5 is connected to the output end of the monitoring circuit 6, so that the monitoring circuit 6 and the first conductive cable 3 form a power-on loop, the first conductive cable 3 is used to be disconnected when the blade root bolt 7 is broken, and the monitoring circuit 6 is used to monitor the on-off status of the first conductive cable 3 in real time. All the blade root bolts 7 in the blade are connected in series by the first conductive cable 3 and form an energized circuit with the monitoring circuit 6. The monitoring circuit 6 can monitor the fracture of the blade root bolt 7 in real time by monitoring the on-off status of the first conductive cable 3 in real time. If the on-off status is detected as a passage, the blade root bolt 7 is not broken; if the on-off status is detected as an open circuit, the blade root bolt 7 is broken. Without manual inspection, the fracture of the blade root bolt 7 can be discovered in time, avoiding missed detection or misdetection due to subjective factors, while also reducing labor costs and greatly improving work efficiency.

[0064] In summary, compared with the existing manual inspection, the first conductive cable of the blade root bolt fracture monitoring system of the present application is connected to the monitoring circuit to form a complete power-on circuit. When the blade root bolt breaks, the power-on circuit is disconnected, thereby realizing the real-time monitoring of the blade root bolt fracture by the monitoring circuit. Frequent manual labor is avoided, and the labor intensity is greatly reduced. At the same time, due to online monitoring, all-weather real-time monitoring can be achieved, avoiding the limitation of manual inspection at night or under bad weather conditions. In addition, since it is automatically detected by the monitoring circuit, the influence of subjective factors is avoided, the situation of missed detection or false detection is reduced, and the accuracy of monitoring is improved. For wind farms, the frequency of manual inspections can be reduced, the consumption of human resources can be reduced, and work efficiency can be improved. The blade root bolt fracture monitoring system can detect problems in time by real-time monitoring of the fracture of the blade root bolt, take corresponding measures, and avoid the loosening or falling off of the blades caused by the fracture of the blade root bolt, thereby reducing the damage of wind power generation equipment, extending the service life of the equipment, and reducing maintenance costs. In addition, since the frequency of manual inspections can be reduced, labor costs can also be reduced and economic benefits can be improved. The blade root bolt is a key component connecting the blade and the hub, and its fracture problem is an important safety hazard. The blade root bolt fracture monitoring system of the present application can detect the fracture of the blade root bolt in time, so as to take corresponding measures to prevent the blade from loosening or falling off, ensure the stable operation of the wind turbine, and improve the stability and safety of the wind turbine. The blade root bolt fracture monitoring system has a simple structure, is easy to install, has low cost, is easy to replace, and the bolts are easy to remove during maintenance, and easy to reinstall after the bolts are maintained. In general, compared with manual inspections, the blade root bolt fracture monitoring system of the present application has higher monitoring efficiency, lower labor intensity, better economic benefits, higher stability and safety of wind turbines, and is low cost.

[0065] Based on the above embodiment, if a noise detection device is installed inside the wind turbine blade and close to the blade root bolt, the wind turbine blade root bolt fracture monitoring method also includes: acquiring the noise signal detected by the noise detection device in real time; preprocessing the noise signal, and extracting features of the preprocessed noise signal to obtain feature parameters; and determining whether the blade root bolt is broken based on the feature parameters.

[0066] The embodiments of the present application do not specifically limit the noise detection device, which can be a high-sensitivity microphone or acoustic sensor. The noise detection device is connected to the main control system through the data acquisition system. Preprocessing the noise signal includes removing the interference components in the noise and enhancing the useful signal for subsequent analysis; common preprocessing methods include: filtering (using a low-pass filter to remove high-frequency interference) and denoising (reducing background noise through wavelet transform or adaptive filtering technology). Feature parameters may include time domain features and frequency domain features. One method of determining whether the blade root bolt is broken based on the feature parameters is to use a machine learning model to judge, and the other is to use a threshold judgment. The threshold judgment is: the threshold of the feature parameter is set based on experience, and when the feature value exceeds the threshold, it is judged that the bolt is broken.

[0067] The judgment method using the machine learning model is to train the model using training data, and the training data includes characteristic parameters of unbroken blade root bolts in the fan blade and characteristic parameters of broken blade root bolts in the fan blade. Using the trained preset machine learning model to determine whether the blade root bolt is broken includes: normalizing each characteristic parameter; combining multiple normalized characteristic parameters into a characteristic vector; inputting the characteristic vector into the preset machine learning model, and determining whether the blade root bolt is broken according to the output result of the preset machine learning model. The embodiment of the present application is efficient in determining whether the blade root bolt is broken by using a preset machine learning model.

[0068] The above is a detailed introduction to a wind turbine blade root bolt fracture monitoring system and method provided by the present application. The various embodiments in the specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same and similar parts between the various embodiments can be referenced to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the relevant parts can be referred to the method part description. It should be pointed out that for ordinary technicians in this technical field, without departing from the principles of the present application, several improvements and modifications can be made to the present application, and these improvements and modifications also fall within the scope of protection of the claims of the present application.

[0069] It should also be noted that, in this specification, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the statement "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device including the element.

Claims

1. A wind turbine blade root bolt fracture monitoring system, characterized in that: include: A wiring socket, a plurality of fixing sockets, a first conductive cable, a first conductive wire, a second conductive wire and a monitoring circuit; The terminal block is installed at the exposed thread on the target blade root bolt in each wind turbine blade, and the fixing block is installed at the exposed thread on each blade root bolt in the wind turbine blade except the target blade root bolt, the terminal block is respectively connected to the first wire and the second wire, the first conductive cable is connected in series with all the fixing blocks in sequence, and the first end of the first conductive cable is connected to the first wire via the terminal block, the second end of the first conductive cable is connected to the second wire via the terminal block, the first wire is connected to the input end of the monitoring circuit, and the second wire is connected to the output end of the monitoring circuit, so that the monitoring circuit and the first conductive cable form a power-on loop, the first conductive cable is used to be disconnected when the blade root bolt is broken, and the monitoring circuit is used to monitor the on-off status of the first conductive cable in real time.

2. The wind turbine blade root bolt fracture monitoring system according to claim 1 is characterized in that: The first conductive cable adopts a copper foil, the terminal block adopts a push-type terminal block, the fixing base is provided with a first through hole, the first connection end of the push-type terminal block is connected to the first wire, the second connection end of the push-type terminal block is connected to the second wire, the first end of the copper foil is connected to the third connection end of the push-type terminal block, the second end of the copper foil passes through the first through hole of each of the fixing bases in turn and is connected to the fourth connection end of the push-type terminal block, the first connection end is electrically connected to the third connection end, and the second connection end is electrically connected to the fourth connection end.

3. The wind turbine blade root bolt fracture monitoring system according to claim 1, characterized in that: The first conductive cable includes a first sub-conductive cable, a second sub-conductive cable and a plurality of third sub-conductive cables, the wiring seat is a first push-type wiring seat, the fixing seat is a second push-type wiring seat, the first wiring end of the first push-type wiring seat is press-connected to the first end of the first sub-conductive cable and the first conductive wire, the second wiring end of the first push-type wiring seat is press-connected to the first end of the second sub-conductive cable and the second conductive wire, the second end of the first sub-conductive cable is press-connected to a second push-type wiring seat adjacent to the first push-type wiring seat, the second end of the second sub-conductive cable is press-connected to another second push-type wiring seat adjacent to the first push-type wiring seat, and the two ends of the third sub-conductive cable are respectively press-connected to two adjacent second push-type wiring seats.

4. The wind turbine blade root bolt fracture monitoring system according to claim 3 is characterized in that: The invention also includes a second conductive cable, wherein the second conductive cable includes a fourth sub-conductive cable, a fifth sub-conductive cable and a plurality of sixth sub-conductive cables, wherein the third terminal of the first push-type wiring seat is firmly connected to the first end of the fourth sub-conductive cable, the fourth terminal of the first push-type wiring seat is firmly connected to the first end of the fifth sub-conductive cable, the second end of the fourth sub-conductive cable is firmly connected to a second push-type wiring seat adjacent to the first push-type wiring seat, the second end of the fifth sub-conductive cable is firmly connected to another second push-type wiring seat adjacent to the first push-type wiring seat, and the two ends of the sixth sub-conductive cable are firmly connected to two adjacent second push-type wiring seats, respectively, the first terminal is electrically connected to the third terminal, the second terminal is electrically connected to the fourth terminal, a conductor is arranged in the second push-type wiring seat, the two terminals of the second push-type wiring seat used to connect the first conductive cable are electrically connected to the two ends of the conductor respectively, and the two terminals of the second push-type wiring seat used to connect the second conductive cable are electrically connected to the two ends of the conductor respectively, so that the second conductive cable and the first conductive cable are connected in parallel.

5. The wind turbine blade root bolt fracture monitoring system according to claim 2 or 3, characterized in that: It also includes an insulating coil, which is used to connect the wiring seat and all the fixing seats in series.

6. The wind turbine blade root bolt fracture monitoring system according to claim 1, characterized in that: The surface of the terminal seat that fits with the target blade root bolt is provided with a thread that is compatible with the target blade root bolt, the surface of the fixing seat that fits with the blade root bolt is provided with a thread that is compatible with the blade root bolt, and the terminal seat is tied to the target blade root bolt through a rubber ring or a cable tie, and the fixing seat is tied to the blade root bolt through a rubber ring or a cable tie.

7. The wind turbine blade root bolt fracture monitoring system according to claim 2, characterized in that: The edge of the copper foil is provided with notches at intervals, and the thickness of the copper foil is 0.05-0.1 mm.

8. A method for monitoring the fracture of blade root bolts of a wind turbine, characterized in that: The wind turbine blade root bolt fracture monitoring system applied to claim 1 comprises: Acquire the on / off status of the first conductive cable in real time; If the on-off condition is detected as a passage, the blade root bolt is not broken; If the on-off condition is detected as an open circuit, the blade root bolt is broken.

9. The method for monitoring the fracture of blade root bolts of a wind turbine according to claim 8, characterized in that: A noise detection device is installed inside the fan blade and near the blade root bolt, and also includes: Acquiring the noise signal detected by the noise detection device in real time; Preprocessing the noise signal, and extracting features from the preprocessed noise signal to obtain feature parameters; Whether the blade root bolt is broken is determined according to the characteristic parameters.

10. The method for monitoring the fracture of blade root bolts of a wind turbine according to claim 9, characterized in that: The determining whether the blade root bolt is broken according to the characteristic parameter comprises: Normalizing each of the characteristic parameters; Combining multiple normalized feature parameters into a feature vector; The feature vector is input into a preset machine learning model, and whether the blade root bolt is broken is determined according to an output result of the preset machine learning model.

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