Fan tower online monitoring system for fastening bolts

Abstract

The invention relates to the technical field of wind power generation, and discloses a fan tower online monitoring system for fastening bolts, which comprises a system module assembly, the system module assembly comprises a data acquisition module, an analysis module, a model establishment module, a test module and a monitoring module, the data acquisition module is connected with the analysis module, and the analysis module is connected with the model establishment module. The analysis module is connected with the model building module, the analysis module analyzes the operation condition of the fan tower drum and determines a bolt stress model at the flange of the tower drum, and the model building module builds a finite element analysis model for bolt fastening and analyzes the evolution rule of the bolt load along with the external load after the external load is applied. The device can effectively reduce the loosening and even breakage conditions of the bolt in the service process, improves the fastening safety of the fan bolt, ensures efficient operation of fan equipment, improves the actual power generation efficiency, does not need to be manually overhauled one by one, saves time and labor, and facilitates long-term reliable operation of the equipment.

Description

Technical Field

[0001] The present invention relates to the technical field of wind power generation, and in particular to an online monitoring system for a wind turbine tower for fastening bolts. Background Art

[0002] Wind power generation technology has achieved rapid development in various aspects such as model design, micro-site selection, construction and installation, and operation control, and the cost per kilowatt-hour has dropped rapidly. However, maintenance costs always account for a considerable proportion of the full life cycle cost of wind power. How to reduce maintenance costs while ensuring the reliable operation of wind turbines has become one of the key issues of concern in the industry. Among them, tower bolts are large in size and quantity, and it is difficult to implement daily monitoring of the remaining preload. During the service of wind turbines, bolt breakage accidents often occur due to the difficulty in comprehensive inspection of bolts.

[0003] Preliminary tests have shown that the design preload of wind turbine tower bolts is only 50-60% of the yield preload, and the preload is significantly dispersed when using traditional torque tightening (the tightening coefficient is about 2), so it is easy to loosen and fatigue fracture during daily operation. During maintenance, each bolt needs to be carefully inspected, which increases the maintenance pressure. As a typical L-type eccentrically loaded bolt, increasing the preload will greatly reduce the bending load on the bolt and improve its ability to withstand extreme working conditions; at the same time, it will greatly extend the bolt preload attenuation cycle, ensure the ability to resist fatigue loads for a long time, and extend the maintenance cycle. Therefore, an online monitoring system for wind turbine towers for tightening bolts is proposed. Summary of the invention

[0004] 1. Technical issues to be solved

[0005] In view of the deficiencies in the prior art, the present invention provides an online monitoring system for wind turbine tower fastening bolts, which solves the problem that wind turbine tower bolts are prone to loosening and fatigue fracture during daily operation, and each bolt needs to be carefully checked during maintenance, which increases the maintenance pressure.

[0006] (II) Technical solution

[0007] In order to achieve the above object, the present invention adopts the following technical solutions:

[0008] An online monitoring system for a wind turbine tower for tightening bolts comprises a system module assembly, wherein the system module assembly comprises a data acquisition module, an analysis module, a model building module, a test module and a monitoring module, wherein the data acquisition module is connected to the analysis module, and the analysis module is connected to the model building module, wherein the analysis module analyzes the operating conditions of the wind turbine tower and determines the bolt stress model at the tower flange, wherein the model building module establishes a finite element analysis model of bolt tightening, analyzes the evolution law of the bolt load with the external load after applying an external load, and evaluates the fatigue damage resistance and safety under the limit load during the service of the bolt, wherein the test module builds a cyclic load test platform simulating the stress under extreme working conditions in the laboratory in accordance with the actual working conditions, wherein the monitoring module is connected to the data acquisition module, and the preload during the bolt tightening process is collected by the data acquisition module, and then the monitoring module monitors and records the complete bolt load data under the external load under extreme working conditions.

[0009] Furthermore, when performing analysis, the analysis module calculates the bolt stress conditions in combination with the external loads borne by the wind turbine during service, and then determines the stress model thereof.

[0010] On the basis of the above scheme, the test module includes a fastening method test and a fastening durability test.

[0011] As a further solution of the present invention, the system module assembly includes a control module. Based on the above-mentioned extreme working condition cyclic loading test platform, the control module implements safety tests under near-yield and yield preloads for high-strength bolts for towers, and provides optimal preload control ranges and control strategies for tower bolts of different specifications.

[0012] Furthermore, the test module applies a single-piece bolt flange load under extreme working conditions in the laboratory, explores the safety of the bolts under extreme working conditions and the evolution law of the tightening force under different preloads, analyzes the safety of the yield limit tightening method under extreme working conditions, and obtains the optimal setting range of the bolt preload.

[0013] On the basis of the above-mentioned scheme, the system module assembly includes a transformation module, which implements intelligent transformation of the existing mechanical pressure-controlled hydraulic tightening wrench pump based on the requirements of the preload control strategy, so that it has the ability to implement angle-related tightening strategies and realize the recording and archiving of all tightening data.

[0014] Furthermore, the system module assembly includes a recording module, which records the daily regular inspection qualification judgment and data records of the pump station.

[0015] The beneficial effects of the present invention are:

[0016] 1. In the present invention, a finite element analysis model of bolt tightening is established through a model building module. After applying an external load, the evolution law of the bolt load with the external load is analyzed, and the fatigue damage resistance of the bolt during service and the safety under the limit load are evaluated.

[0017] 2. The present invention can effectively reduce the loosening or even breakage of bolts during service, improve the safety of fan bolt tightening, ensure the efficient operation of fan equipment, improve the actual power generation efficiency, and eliminate the need for manual maintenance one by one, saving time and effort, which is conducive to the long-term reliable operation of the equipment.

[0018] 3. In the present invention, based on the test results, a setting criterion for the tightening force of the wind turbine tower bolts is compiled, and the optimal tightening force is used as the control target during subsequent bolt replacement or new wind turbine construction to improve the preload control level as safely as possible.

[0019] 4. In the present invention, the control module is based on the above-mentioned extreme working condition cyclic loading test platform, implements safety tests under near-yield and yield preloads for high-strength bolts for towers, and provides the optimal preload control range and control strategy for tower bolts of different specifications. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 A schematic diagram of the system framework process structure of an online monitoring system for wind turbine towers for tightening bolts proposed by the present invention. DETAILED DESCRIPTION

[0021] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. It should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "setting" should be understood in a broad sense. For ordinary technicians in this field, the specific meanings of the above terms in this patent can be understood according to specific circumstances.

[0022] Example 1

[0023] Reference Figure 1, an online monitoring system for a wind turbine tower for tightening bolts, including a system module assembly, the system module assembly including a data acquisition module, an analysis module, a model building module, a test module and a monitoring module, the data acquisition module is connected to the analysis module, and the analysis module is connected to the model building module, the analysis module analyzes the operating conditions of the wind turbine tower, determines the bolt force model at the tower flange, the model building module establishes a finite element analysis model of bolt tightening, and the model building module further accurately analyzes the force conditions of the bolts and flange surfaces under different tightening schemes, analyzes the evolution law of the bolt load with the external load after applying the external load, and performs a finite element analysis on the bolt. The fatigue damage resistance and safety under extreme loads of the bolts during service are evaluated. The test module builds a cyclic load test platform that simulates extreme working conditions in the laboratory according to actual working conditions. The monitoring module is connected to the data acquisition module. The preload force during the bolt tightening process is collected through the data acquisition module, and then the monitoring module monitors and records the complete bolt load data under extreme external loads. This can effectively reduce the loosening or even breakage of the bolts during service, improve the safety of the wind turbine bolt tightening, ensure the efficient operation of the wind turbine equipment, and improve the actual power generation efficiency. There is no need for manual maintenance one by one, which saves time and effort and is conducive to the long-term reliable operation of the equipment.

[0024] In the present invention, the analysis module calculates the stress of the bolts in combination with the external loads borne by the wind turbine during service, and then determines its stress model. The test module includes a fastening method test and a fastening durability test. The system module assembly includes a control module. The control module is based on the above-mentioned extreme working condition cyclic loading test platform, and implements safety tests under near-yield and yield preloads for high-strength bolts for towers, and provides optimal preload control ranges and control strategies for tower bolts of different specifications. The test module applies a monolithic bolt flange load under extreme working conditions in the laboratory, explores the safety of bolts under extreme working conditions under different preloads (planned 70-100% yield limit preloads) and the evolution law of fastening force, analyzes the safety of the yield limit fastening method under extreme working conditions, obtains the optimal setting range of the bolt preload, and compiles the wind turbine tower bolt fastening force setting criteria based on the test results. The optimal fastening force is used as the control target during subsequent bolt replacement or new wind turbine construction to improve the preload control level as safely as possible.

[0025] Example 2

[0026] Reference Figure 1, an online monitoring system for a wind turbine tower for tightening bolts, including a system module assembly, the system module assembly including a data acquisition module, an analysis module, a model building module, a test module and a monitoring module, the data acquisition module is connected to the analysis module, and the analysis module is connected to the model building module, the analysis module analyzes the operating conditions of the wind turbine tower, determines the bolt force model at the tower flange, the model building module establishes a finite element analysis model of bolt tightening, and the model building module further accurately analyzes the force conditions of the bolts and flange surfaces under different tightening schemes, analyzes the evolution law of the bolt load with the external load after applying the external load, and performs a finite element analysis on the bolt. The fatigue damage resistance and safety under extreme loads of the bolts during service are evaluated. The test module builds a cyclic load test platform that simulates extreme working conditions in the laboratory according to actual working conditions. The monitoring module is connected to the data acquisition module. The preload force during the bolt tightening process is collected through the data acquisition module, and then the monitoring module monitors and records the complete bolt load data under extreme external loads. This can effectively reduce the loosening or even breakage of the bolts during service, improve the safety of the wind turbine bolt tightening, ensure the efficient operation of the wind turbine equipment, and improve the actual power generation efficiency. There is no need for manual maintenance one by one, which saves time and effort and is conducive to the long-term reliable operation of the equipment.

[0027] In the present invention, the analysis module calculates the stress of the bolts in combination with the external loads borne by the wind turbine during service, and then determines its stress model. The test module includes a fastening method test and a fastening durability test. The system module assembly includes a control module. The control module is based on the above-mentioned extreme working condition cyclic loading test platform, and implements safety tests under near-yield and yield preloads for high-strength bolts for towers, and provides optimal preload control ranges and control strategies for tower bolts of different specifications. The test module applies a monolithic bolt flange load under extreme working conditions in the laboratory, explores the safety of bolts under extreme working conditions under different preloads (planned 70-100% yield limit preloads) and the evolution law of fastening force, analyzes the safety of the yield limit fastening method under extreme working conditions, obtains the optimal setting range of the bolt preload, and compiles the wind turbine tower bolt fastening force setting criteria based on the test results. The optimal fastening force is used as the control target during subsequent bolt replacement or new wind turbine construction to improve the preload control level as safely as possible.

[0028] In particular, the system module assembly includes a transformation module. Based on the requirements of the preload control strategy, the transformation module implements intelligent transformation of the existing mechanical pressure-controlled hydraulic tightening wrench pump, so that it has the ability to implement angle-related tightening strategies and realize the recording and archiving of all tightening data. The system module assembly includes a recording module. The recording module records the daily regular inspection and qualified judgment and data records of the pump station.

[0029] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. An online monitoring system for a wind turbine tower for tightening bolts, comprising a system module assembly, characterized in that: The system module assembly includes a data acquisition module, an analysis module, a model building module, a test module and a monitoring module. The data acquisition module is connected to the analysis module, and the analysis module is connected to the model building module. The analysis module analyzes the operating conditions of the wind turbine tower and determines the bolt force model at the tower flange. The model building module establishes a finite element analysis model of bolt tightening, analyzes the evolution law of the bolt load with the external load after applying the external load, and evaluates the fatigue damage resistance and safety of the bolt under the ultimate load during the service process. The test module builds a cyclic load test platform simulating extreme working conditions in the laboratory according to the actual working conditions. The monitoring module is connected to the data acquisition module, and the preload force during the bolt tightening process is collected through the data acquisition module. Then the monitoring module monitors and records the complete bolt load data under the external load of the extreme working condition.

2. The wind turbine tower online monitoring system for fastening bolts according to claim 1 is characterized in that: When performing analysis, the analysis module calculates the bolt stress conditions in combination with the external loads borne by the wind turbine during service, and then determines the stress model thereof.

3. The wind turbine tower online monitoring system for fastening bolts according to claim 1, characterized in that: The test module includes a fastening method test and a fastening durability test.

4. The wind turbine tower online monitoring system for fastening bolts according to claim 3 is characterized in that: The system module assembly includes a control module. Based on the above-mentioned extreme working condition cyclic loading test platform, the control module implements safety tests under near-yield and yield preloads for high-strength bolts for towers, and provides optimal preload control ranges and control strategies for tower bolts of different specifications.

5. The wind turbine tower online monitoring system for fastening bolts according to claim 1, characterized in that: The test module applies a single bolt flange load under extreme working conditions in the laboratory, explores the safety of the bolts under extreme working conditions and the evolution law of the tightening force under different preloads, analyzes the safety of the yield limit tightening method under extreme working conditions, and obtains the optimal setting range of the bolt preload.

6. The wind turbine tower online monitoring system for fastening bolts according to claim 5, characterized in that: The system module assembly includes a transformation module, which implements intelligent transformation of the existing mechanical pressure-controlled hydraulic tightening wrench pump based on the pre-tightening force control strategy requirements, so that it has the ability to implement angle-related tightening strategies and realizes the recording and archiving of all tightening data.

7. The wind turbine tower online monitoring system for fastening bolts according to claim 6, characterized in that: The system module assembly includes a recording module, which records the daily regular inspection qualification judgment and data records of the pump station.

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