Blade bolt fracture monitoring system

Abstract

The utility model relates to a blade bolt fracture monitoring system comprising a plurality of photoelectric sensors arranged on a hub, and a photoelectric reflector plate is arranged right opposite to each photoelectric sensor; the photoelectric sensor continuously emits light spots, the light spots are reflected through the photoelectric reflector plate opposite to the photoelectric sensor to form a passage, light spot reflection is interrupted when a blade bolt passes through the passage, and a circuit break signal is generated. Compared with the prior art, the photoelectric sensor is arranged on the hub, the blade root bolt state is monitored in real time along with rotation of the blade under the condition that a variable pitch strategy is not changed, signals are transmitted to the wireless receiver arranged in the main control cabinet through the wireless signal transmitter, dependence on configuration in a fan hub system is avoided to the maximum extent, and the blade root bolt state is monitored in real time. The wireless receiver transmits signals to a background through an existing wind field network, the running state of the blade root bolt is monitored in real time, and under the condition that the blade root bolt is broken, relevant measures are taken at the first time, so that the running safety and reliability of the fan are improved.

Description

Technical Field

[0001] The utility model relates to the field of bolt fracture detection, in particular to a blade bolt fracture monitoring system. Background Art

[0002] The basic principle of wind power generation is that the kinetic energy of wind is converted into mechanical energy through the wind turbine of the wind turbine, and then drives the generator of the wind turbine to generate electricity and convert it into electrical energy. The connection between the blade root and the hub in the wind turbine is generally connected by pre-embedded blade root high-strength bolts.

[0003] Due to the strong wind torque and the vibration of the wind turbine itself during operation, the connection bolts between the blade root and the hub are prone to loosening, resulting in the failure of the wind turbine to operate normally. For example, the connection bolts at the tower joint are loose, and the bolts in the flange connection structure are subjected to tension and compression cycles under the action of alternating loads. Under the action of alternating loads of tension and compression, the thread undergoes plastic deformation, causing the bolts to break or become seriously loose, thus affecting the normal operation of the unit. In severe cases, it may even cause accidents such as blade falling and tower collapse, causing great economic losses to wind power companies. Utility Model Content

[0004] The purpose of the present utility model is to provide a blade bolt fracture monitoring system in order to overcome at least one of the defects of the above-mentioned prior art. The photoelectric sensor is arranged on the hub. Without changing the pitch strategy, the system monitors the status of the blade root bolt in real time as the blade rotates. In the standard configuration, a wireless signal transmitter is used to transmit the signal to a wireless receiver arranged in the main control cabinet, which can avoid dependence on the configuration of the wind turbine hub system to the greatest extent. The wireless receiver can transmit the signal to the background through the existing wind farm network, monitor the operating status of the blade root bolt in real time, and take relevant measures at the first time when the blade root bolt is broken to improve the safety and reliability of the wind turbine operation.

[0005] Taking into account the diversity of on-site environments, the entire solution can be selected by the customer to monitor the bolts in a specified area or all bolts. It can also establish a wind farm ring network and use pitch signal transmission according to the on-site configuration. The entire solution can be customized and has good adaptability to various configuration environments.

[0006] The purpose of the utility model can be achieved through the following technical solutions:

[0007] A blade bolt fracture monitoring system, the system comprising:

[0008] A plurality of photoelectric sensors are arranged on the wheel hub, and a photoelectric reflector is arranged directly opposite each of the photoelectric sensors;

[0009] The photoelectric sensor continuously emits a light spot, and reflects the light spot through the photoelectric reflective sheet directly opposite to it to form a path. When the blade bolt passes through the path, the light spot reflection is interrupted, and a circuit breaker signal is generated.

[0010] Specifically, when the blade bolts and the spacing between adjacent blade bolts pass through the passage, different pulse signals are continuously generated. Each photoelectric sensor will intercept and compare them with each other to determine whether the bolt is broken. At the same time, each photoelectric sensor will also intercept signals at different time periods for self-comparison. Finally, the judgment result will be transmitted and received through wireless signals and passed to the background for early warning.

[0011] Further, when the blade bolt passes through the passage, the blade bolt faces the photoelectric sensor.

[0012] Furthermore, the system is also provided with a wireless transmitter connected to the photoelectric sensor, which is used to send the signal transmitted by the photoelectric sensor to a wireless receiver arranged in the main control cabinet.

[0013] Furthermore, the system is also provided with a wireless transmitter connected to the photoelectric sensor, and the wireless transmitter transmits a wireless signal to a monitoring data processor arranged at the bottom of the tower.

[0014] Furthermore, the photoelectric sensor feeds back a signal to the pitch control electrical cabinet, which is then connected to the main control via a slip ring, and the judgment logic is implemented in the main control.

[0015] Furthermore, the wireless transmitter and the wireless receiver have a waterproof rating of IP54 and an anti-corrosion rating of C4-H, a high and low temperature operating range of [-40°C, 80°C], and meet the EN 61000 electromagnetic anti-interference requirements, with reliable performance.

[0016] Furthermore, a plurality of the photoelectric sensors are mounted on the hub along the circumferential direction; and the linear speed of the blade pitch change is consistent for each of the photoelectric sensors.

[0017] Furthermore, there are at least two photoelectric sensors.

[0018] Furthermore, the system is also provided with a mounting bracket mounted on the wheel hub; the photoelectric sensor is fixed on the wheel hub via the mounting bracket.

[0019] Furthermore, the mounting bracket is a mounting bracket with adjustable size, ensuring that the photoelectric sensor mounted thereon can face the center of the blade bolt.

[0020] Furthermore, the mounting bracket is connected to the wheel hub via bolts.

[0021] Compared with the prior art, the utility model has the following advantages:

[0022] (1) The utility model completes the entire signal transmission and judgment without changing the pitch control logic and the main control logic, reduces the dependence on the wind turbine configuration, and further enhances the adaptability;

[0023] (2) Although the pitch speed is changing, the linear speed of the pitch is consistent for each sensor at the same time. By judging the signal difference between sensors and setting the threshold method, the traditional counting alarm idea can be eliminated. The whole system has lower cost, lower interface requirements, and stronger universality.

[0024] (3) The standard solution uses wireless transmitters and receivers to complete signal collection, judgment and transmission, which has low requirements for installation location, space and distance. According to the configuration of wind turbines, it can also be used to judge and transmit signals through the pitch channel in wind farm component ring networks without wind farm networks and in wind farms with redundant pitch signal channels;

[0025] (4) The wireless signal transmitter and wireless receiver are the core of the whole solution. Their waterproof level can reach IP54, the anti-corrosion level can reach C4-H, the high and low temperature operating range meets [-40℃, 80℃], and they meet the EN 61000 electromagnetic interference resistance requirements, with reliable performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is a schematic diagram of a blade bolt fracture monitoring system in Example 1;

[0027] Figure 2 for Figure 1 Installation diagram of wireless transmitter and photoelectric sensor;

[0028] Figure 3 for Figure 1 Installation diagram of photoelectric sensor;

[0029] Figure 4 This is a signal transmission process diagram of the blade bolt fracture monitoring system in Example 1;

[0030] Figure 5 This is a signal transmission process diagram of the blade bolt fracture monitoring system in Example 2;

[0031] Figure 6 This is a signal transmission process diagram of the blade bolt fracture monitoring system in Example 3;

[0032] Numbers in the figure indicate: 1-photoelectric sensor; 2-wireless transmitter; 3-mounting bracket. DETAILED DESCRIPTION

[0033] The present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. This embodiment is implemented based on the technical solution of the present invention, and provides a detailed implementation method and specific operation process, but the protection scope of the present invention is not limited to the following embodiments.

[0034] Example 1

[0035] See also Figure 1-3 A blade bolt fracture monitoring system, the system comprises: a plurality of photoelectric sensors 1 arranged on a wheel hub, each of the photoelectric sensors 1 is provided with a photoelectric reflector directly opposite; the photoelectric sensor 1 continuously emits a light spot, and reflects the light spot through the photoelectric reflector directly opposite to form a path, when the blade bolt passes through the path, the light spot reflection is interrupted, and a circuit breaker signal is generated. When the blade bolt passes through the path, the blade bolt is directly opposite to the photoelectric sensor 1.

[0036] In this embodiment, the system is further provided with an L-shaped mounting bracket 3 mounted on the wheel hub. The mounting bracket 3 is connected to the wheel hub via bolts, and the photoelectric sensor 1 is fixed to the wheel hub via the mounting bracket 3 .

[0037] There may be multiple photoelectric sensors 1 , and in this embodiment, there are four photoelectric sensors 1 . The four photoelectric sensors 1 are evenly installed on the hub along the circumferential direction; the linear speed of the blade pitch change is consistent for each photoelectric sensor 1 .

[0038] In this embodiment, the system is further provided with a wireless transmitter 2 connected to the photoelectric sensor 1, which is used to send the signal transmitted by the photoelectric sensor 1 to a wireless receiver arranged in the main control cabinet. The signal transmission process is shown in FIG. Figure 4 The wireless transmitter 2 and the wireless receiver have a waterproof rating of IP54 and an anti-corrosion rating of C4-H. The high and low temperature operating range meets [-40°C, 80°C], and meets the EN 61000 electromagnetic anti-interference requirements, with reliable performance.

[0039] The process of building the blade bolt fracture monitoring system of this embodiment is as follows:

[0040] (1) Install the photoelectric sensor 1 on the selected area. The photoelectric sensor 1 is connected to the wheel hub through the mounting bracket 3. The installed photoelectric sensor 1 must be ensured to be aligned with the blade bolt to avoid errors caused by excessive deflection angles on system operation.

[0041] (2) A special reflective sticker, i.e., a photoelectric reflective sheet, is pasted directly opposite the photoelectric sensor 1 to reflect the received light signal and thereby form a pathway;

[0042] (3) Connect the wireless transmitter 2 to the wheel hub by installing the sheet metal, and fix the power adapter and signal cable;

[0043] (4) Pull power from the hub pitch system by using existing plugs, glands, and modified light cables to connect the power cable and the photoelectric sensor cable to the wireless transmitter 2;

[0044] (5) The wireless receiver is placed in the main control cabinet to receive the signal sent by the wireless transmitter 2, and uses the network port in the main control cabinet to transmit the judged signal back to the background for early warning.

[0045] (6) After the system is installed, the photoelectric sensor position, operating status and signal output need to be debugged. After debugging is completed, the system is put into operation.

[0046] Working principle:

[0047] Photoelectric sensor 1 can be installed to monitor special areas and full-angle monitoring as needed. In order to avoid the speed difference caused by component acceleration to the maximum extent, photoelectric sensor 1 will be arranged directly opposite the center of the blade bolt, and the mounting bracket 3 will also have a size adjustment function to ensure that the above requirements are met. Photoelectric sensor 1 continuously emits a light spot, and reflects the light spot through the photoelectric reflector directly opposite to form a path. When the blade bolt passes by, the light spot reflection is interrupted, generating a circuit breaker signal.

[0048] By continuously switching on and off the signal, the signal time of each photoelectric sensor 1 passing through three bolts at the same time is captured, and the signal time periods of each photoelectric sensor 1 are compared; since the linear speed of the entire circle is constant at the same time, different pulse information will be generated when the blade bolt passes and the blade bolt spacing passes. Each photoelectric sensor 1 performs time comparison under the same pulse band to determine whether there is a difference. The difference is that the bolt status is abnormal. To avoid false alarms, the threshold is set to 50%. If the threshold is exceeded, an early warning is triggered.

[0049] The wireless transmitter 2 receives the signal of each photoelectric sensor in real time and transmits the signal data to the wireless signal receiver. The wireless signal receiver completes the signal reception and judgment, and feeds back the judgment result and original data to the background through the wind turbine network interface. The background can observe the running status of the blade bolt in real time. When the blade bolt breaks or the equipment fails, an early warning can be issued on the background interface.

[0050] Example 2

[0051] This embodiment is basically the same as the embodiment 1, except for the difference in the wireless receiving signal processing and transmission mode. The wireless transmitter 2 of this embodiment transmits the wireless signal to the monitoring data processor arranged at the bottom of the tower. By building a new ring network in the wind farm wind turbine, the signal is concentrated in the booster station, equipped with a core switch and a processor, the signal is logically judged, and the processing result is displayed on the background interface. The signal transmission process is shown in FIG. Figure 5 .

[0052] Example 3

[0053] This embodiment is basically the same as the embodiment 1, except for the transmission mode of the photoelectric sensor signal. The photoelectric sensor 1 of this embodiment feeds back the signal to the pitch electrical cabinet to complete the power supply borrowing and signal channel borrowing, and connects the signal to the main control along with the slip ring. The signal processing is completed by the judgment logic integrated in the main control, and finally the signal is transmitted to the background interface via the main control signal. The signal transmission process is shown in Figure 6 .

[0054] The above is only the preferred embodiment of the utility model, and does not limit the utility model in other forms. Any technician familiar with the profession may use the technical content disclosed above to change or modify it into an equivalent embodiment with equivalent changes. However, any simple modification, equivalent change and modification made to the above embodiment based on the technical essence of the utility model without departing from the technical solution of the utility model still belongs to the protection scope of the technical solution of the utility model.

Claims

1. A blade bolt fracture monitoring system, characterized in that: The system includes: A plurality of photoelectric sensors (1) are arranged on the wheel hub, each of the photoelectric sensors (1) being provided with a photoelectric reflector directly opposite thereto; The photoelectric sensor (1) continuously emits a light spot, and reflects the light spot through the photoelectric reflective sheet directly opposite to it to form a path; When the blade bolts and the spacing between adjacent blade bolts pass through the passage, different pulse signals are continuously generated, and each photoelectric sensor (1) intercepts and compares them with each other to determine whether the bolt is broken. At the same time, each photoelectric sensor (1) also intercepts signals at different time periods for self-comparison, and finally transmits and receives the judgment result through wireless signals and transmits it to the background for early warning.

2. A blade bolt fracture monitoring system according to claim 1, characterized in that: When the blade bolt passes through the passage, the blade bolt faces the photoelectric sensor (1).

3. A blade bolt fracture monitoring system according to claim 1, characterized in that: The system is also provided with a wireless transmitter (2) connected to the photoelectric sensor (1) and used for sending the signal transmitted by the photoelectric sensor (1) to a wireless receiver arranged in the main control cabinet.

4. A blade bolt fracture monitoring system according to claim 1, characterized in that: The system is also provided with a wireless transmitter (2) connected to the photoelectric sensor (1), and the wireless transmitter (2) transmits a wireless signal to a monitoring data processor arranged at the bottom of the tower.

5. A blade bolt fracture monitoring system according to claim 1, characterized in that: The photoelectric sensor (1) feeds back a signal to the pitch control electrical cabinet, which is then connected to the main control via a slip ring, and the judgment logic is implemented in the main control.

6. A blade bolt fracture monitoring system according to claim 1, characterized in that: A plurality of the photoelectric sensors (1) are mounted on the hub along the circumferential direction; the linear speed of the blade pitch change is consistent for each of the photoelectric sensors (1).

7. A blade bolt fracture monitoring system according to claim 1, characterized in that: There are at least two photoelectric sensors (1).

8. The blade bolt fracture monitoring system according to claim 1, characterized in that: The system is also provided with a mounting bracket (3) mounted on the wheel hub; the photoelectric sensor (1) is fixed on the wheel hub via the mounting bracket (3).

9. A blade bolt fracture monitoring system according to claim 8, characterized in that: The mounting bracket (3) is a mounting bracket with adjustable size.

10. A blade bolt fracture monitoring system according to claim 8, characterized in that: The mounting bracket (3) is connected to the wheel hub via bolts.

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