Mixed tower fan prestress intelligent tensioning system and dynamic control method thereof

Abstract

The invention discloses a mixed tower fan prestress intelligent tensioning system and a dynamic control method thereof. The mixed tower fan prestress intelligent tensioning system comprises a Beidou displacement monitor, a temperature sensor, a tensioning jack, a hydraulic pump station, a force measuring sensor, an optical fiber sensor and an intelligent control system, the Beidou displacement monitor is arranged at the top of a concrete tower drum, the temperature sensor is arranged on a steel strand, the tensioning jack is connected with the hydraulic pump station, and the force measuring sensor is connected with the optical fiber sensor. The force measuring sensors are arranged on the steel strands on the outer sides of the working anchors, displacement sensors and pressure sensors are arranged on the tensioning jacks, and the optical fiber sensors are arranged on a tower drum of the concrete tower. The intelligent control system is in communication connection with the Beidou displacement monitor, the temperature sensor, the hydraulic pump station, the force measurement sensor, the displacement sensor, the pressure sensor and the optical fiber sensor. The construction efficiency and the construction precision can be greatly improved, the construction period is shortened, and the construction cost is reduced.

Description

Technical Field

[0001] This invention relates to the field of prestressed construction technology in civil engineering, specifically to a prestressed intelligent tensioning system for hybrid tower wind turbines and its dynamic control method. Background Technology

[0002] In the prestressing tensioning construction of tall concrete structures such as wind turbine towers and chimneys, traditional tensioning methods rely on manual experience, resulting in low synchronization accuracy (>±5%), which can easily lead to uneven stress distribution in the tower body and tower deviation exceeding limits. Furthermore, the monitoring of prestress loss is lagging, and existing technologies cannot compensate for friction loss in real time, especially the friction loss at the anchor ring. At the same time, tensioning data is recorded in a discrete manner, lacking full-cycle digital traceability, resulting in chaotic tensioning records. In addition, ultra-long steel strands (>100m) are significantly affected by temperature fluctuations, and traditional tensioning methods have not established a temperature compensation model. Summary of the Invention

[0003] To address the technical problems mentioned above, this invention provides a prestressed intelligent tensioning system for hybrid tower wind turbines and its dynamic control method, which can greatly improve construction efficiency and accuracy, shorten the construction period, and reduce construction costs.

[0004] This invention provides a prestressed intelligent tensioning system for a mixed-tower wind turbine, comprising a Beidou displacement monitor, a temperature sensor, tensioning jacks, a hydraulic pump station, a force sensor, an optical fiber sensor, and an intelligent control system. The Beidou displacement monitor is spaced apart at the top of the concrete tower. The temperature sensors are respectively installed on the steel strands inside the concrete tower. The tensioning jacks are respectively installed at the bottom ends of the steel strands and connected to the hydraulic pump station. The force sensors are respectively installed on the steel strands outside each working anchor. Each tensioning jack is equipped with a displacement sensor and a pressure sensor. The optical fiber sensors are respectively installed on the concrete tower. The intelligent control system is located on the hydraulic pump station and is communicatively connected to the Beidou displacement monitor, the temperature sensor, the hydraulic pump station, the force sensor, the displacement sensor, the pressure sensor, and the optical fiber sensor.

[0005] In a preferred embodiment of the prestressed intelligent tensioning system for hybrid tower wind turbines provided by the present invention, the optical fiber sensors are evenly divided into multiple groups, and the multiple groups of optical fiber sensors are evenly arranged along the height direction of the concrete tower.

[0006] In a preferred embodiment of the prestressed intelligent tensioning system for hybrid tower wind turbines provided by the present invention, the fiber optic sensors are evenly divided into five groups, with four fiber optic sensors in each group, and the four fiber optic sensors are evenly arranged along the circumference of the concrete tower cylinder.

[0007] This invention also provides a dynamic control method for a prestressed intelligent tensioning system for hybrid tower wind turbines, comprising the following steps: Step 1: First, install the Beidou displacement monitoring instrument and fiber optic sensor at the corresponding positions on the concrete tower cylinder. Then, install the temperature sensor, tensioning jack, and force sensor at the corresponding positions on the steel strands. Install the displacement sensor and pressure sensor on the tensioning jack. Next, connect the tensioning jack to the hydraulic pump station. Then, connect the Beidou displacement monitoring instrument, the temperature sensor, the hydraulic pump station, the force sensor, the displacement sensor, the pressure sensor, and the fiber optic sensor to the intelligent control system for communication. Step 2: Perform graded coordinated tensioning on the concrete tower cylinder, and carry out prestress loss compensation and abnormal state monitoring.

[0008] In a preferred embodiment of the dynamic control method for the prestressed intelligent tensioning system of the hybrid tower wind turbine provided by the present invention, the graded coordinated tensioning includes: Pre-tensioning stage: Synchronous tensioning of the annular symmetrical point group is carried out according to 10% of the design tension value, the synchronization error is controlled to be ≤2%, and abnormal conditions are monitored; The main tensioning stage: The prestressing tensioning adopts dual control of pressure value and elongation. The loading rate is dynamically adjusted according to strain feedback, the synchronization error is controlled to be ≤1.5%, and abnormal conditions are monitored. After reaching 100% of the design tension value, the load holding stage is entered. During the load-bearing stage: Automatic prestress loss compensation is performed at regular intervals, and abnormal conditions are monitored to control the pressure stabilization at ±0.3MPa.

[0009] In a preferred embodiment of the dynamic control method for the prestressed intelligent tensioning system of the hybrid tower wind turbine provided by the present invention, the loading rate is dynamically adjusted based on strain feedback, and the calculation method for the loading rate is as follows: v=vθ×(1-|Δε_i / ε_avg|) Where Δε_i is the strain deviation at point i, and ε_avg is the mean strain.

[0010] In a preferred embodiment of the dynamic control method for the prestressed intelligent tensioning system of the hybrid tower wind turbine provided by the present invention, the abnormal state monitoring adopts a graded early warning strategy, including: The pressure of the corresponding tensioning jack is monitored by each pressure sensor. When a local pressure deviation is greater than 5%, the corresponding tensioning jack will automatically decelerate until the pressure value of the corresponding tensioning jack returns to normal. The strain value at each point is monitored by various fiber optic sensors. When a sudden change in strain value >10% occurs, tensioning is paused and three-dimensional scanning is initiated. The tilt of the concrete tower is monitored by a Beidou displacement monitoring instrument. When the tilt is greater than 0.1°, emergency pressure relief is carried out until the tilt returns to normal.

[0011] In a preferred embodiment of the dynamic control method for the prestressed intelligent tensioning system of the hybrid tower wind turbine provided by the present invention, the method for calculating the inclination is as follows: θ=a×(F_left- F_right)+b×(T_top-T_bottom).

[0012] In a preferred embodiment of the dynamic control method for the intelligent prestressing tensioning system of the hybrid tower wind turbine provided by the present invention, the prestress loss compensation is adjusted in a closed loop every 5 minutes, and its calculation method is as follows: Δσ_corr=k1×ΔT+k2×In(t)+k3×ε_creep Where k1 is the temperature loss coefficient, k2 is the time loss coefficient, and k3 is the creep coefficient.

[0013] Compared with existing technologies, the intelligent prestressed tensioning system and its dynamic control method for hybrid tower wind turbines provided by this invention have the following beneficial effects: By using a multi-source sensor array composed of a Beidou displacement monitor, temperature sensor, force sensor, displacement sensor, pressure sensor and fiber optic sensor, and performing automatic prestress loss compensation during the tensioning process, compared with traditional tensioning methods, the tensioning synchronization accuracy can be improved from ±5% to ±0.8%, the active compensation efficiency for prestress loss can be improved by 40%, and the tensioning period can be shortened by 30%, which can greatly improve construction efficiency and accuracy, shorten the construction period and reduce construction costs. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort, wherein: Figure 1 This is a structural schematic diagram of the prestressed intelligent tensioning system for hybrid tower fans provided by the present invention; Figure 2 This is a schematic diagram of the installation of the force sensor in this invention; Figure 3 This is a schematic diagram of the installation of the displacement sensor and pressure sensor with the tensioning jack in this invention; Figure 4 This is a structural block diagram of the prestressed intelligent tensioning system for hybrid tower wind turbines provided by the present invention; Figure 5This is a flowchart of the dynamic control method for the prestressed intelligent tensioning system of the hybrid tower wind turbine provided by the present invention. Detailed Implementation

[0015] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0016] Please refer to the following: Figure 1 , Figure 2 , Figure 3 and Figure 4 ,in, Figure 1 This is a structural schematic diagram of the prestressed intelligent tensioning system for hybrid tower wind turbines provided by the present invention; Figure 2 This is a schematic diagram of the installation of the force sensor in this invention; Figure 3 This is a schematic diagram of the installation of the displacement sensor and pressure sensor with the tensioning jack in this invention; Figure 4 This is a structural block diagram of the intelligent prestressing tensioning system for hybrid tower wind turbines provided by the present invention. The intelligent prestressing tensioning system for hybrid tower wind turbines includes a Beidou displacement monitor 11, a temperature sensor 12, tensioning jacks 13, a hydraulic pump station 14, a force sensor 15, an optical fiber sensor 16, and an intelligent control system 17. The Beidou displacement monitor 11 is spaced apart on the top of the concrete tower cylinder 21. The temperature sensors 12 are respectively installed on the steel strands 22 inside the concrete tower cylinder 21. The tensioning jacks 13 are respectively installed at the bottom ends of the steel strands 22 and connected to the hydraulic pump station 14. The force sensor... Devices 15 are respectively installed on the steel strands 22 outside each working anchor 18. Displacement sensors 19 and pressure sensors 20 are respectively installed on each tensioning jack 13. Fiber optic sensors 16 are respectively installed on the concrete tower cylinder 21. The intelligent control system 17 is installed on the hydraulic pump station 14 and is communicatively connected to the Beidou displacement monitoring instrument 11, the temperature sensor 12, the hydraulic pump station 14, the force sensor 15, the displacement sensor 19, the pressure sensor 20, and the fiber optic sensor 16.

[0017] Furthermore, the temperature sensors 12 are divided into two groups, with the two groups of temperature sensors 12 arranged vertically at intervals, and the number of temperature sensors 12 in each group corresponds to the number of steel strands 22.

[0018] Furthermore, the fiber optic sensors 16 are evenly divided into multiple groups, and the multiple groups of fiber optic sensors 16 are evenly arranged along the height direction of the concrete tower cylinder 21.

[0019] Specifically, the fiber optic sensors 16 are evenly divided into five groups, with four fiber optic sensors 16 in each group, and the four fiber optic sensors 16 are evenly arranged along the circumference of the concrete tower cylinder 21.

[0020] Please see Figure 5 , Figure 5 This is a flowchart of the dynamic control method for the prestressed intelligent tensioning system of the hybrid tower wind turbine provided by the present invention.

[0021] The dynamic control method of the prestressed intelligent tensioning system for hybrid tower wind turbines includes the following steps: Step S1: First, install the Beidou displacement monitoring instrument 11 and the fiber optic sensor 16 at the corresponding positions on the concrete tower cylinder 21. Install the temperature sensor 12, the tensioning jack 13, and the force sensor 15 at the corresponding positions on the steel strand 22. Install the displacement sensor 19 and the pressure sensor 20 on the tensioning jack 13. Then, connect the tensioning jack 13 to the hydraulic pump station 14. Connect the Beidou displacement monitoring instrument 11, the temperature sensor 12, the hydraulic pump station 14, the force sensor 15, the displacement sensor 19, the pressure sensor 20, and the fiber optic sensor 16 to the intelligent control system 17 for communication.

[0022] Specifically, the temperature sensors 12 are divided into two groups, with the two groups of temperature sensors 12 arranged vertically at intervals, and the number of temperature sensors 12 in each group corresponds to the number of steel strands 22.

[0023] The fiber optic sensors 16 are evenly divided into multiple groups, and the multiple groups of fiber optic sensors 16 are evenly arranged along the height direction of the concrete tower cylinder 21.

[0024] Step S2: Perform graded coordinated tensioning on the concrete tower cylinder, and perform prestress loss compensation and abnormal state monitoring.

[0025] Specifically, the hierarchical coordinated tensioning includes: Pre-tensioning stage: Synchronous tensioning of the annular symmetrical point group is carried out according to 10% of the design tension value, the synchronization error is controlled to be ≤2%, and abnormal conditions are monitored; The main tensioning stage: The prestressing tensioning adopts dual control of pressure value and elongation. The loading rate is dynamically adjusted according to strain feedback, the synchronization error is controlled to be ≤1.5%, and abnormal conditions are monitored. After reaching 100% of the design tension value, the load holding stage is entered. During the load-bearing stage: Automatic prestress loss compensation is performed at regular intervals, and abnormal conditions are monitored to control the pressure stabilization at ±0.3MPa.

[0026] The prestress loss compensation is adjusted in a closed loop every 5 minutes, and its calculation method is as follows: Δσ_corr=k1×ΔT+k2×In(t)+k3×ε_creep Where k1 is the temperature loss coefficient, k2 is the time loss coefficient, and k3 is the creep coefficient.

[0027] The loading rate is dynamically adjusted based on strain feedback, and the calculation method for the loading rate is as follows: v=vθ×(1-|Δε_i / ε_avg|) Where Δε_i is the strain deviation at point i, and ε_avg is the mean strain.

[0028] The abnormal status monitoring adopts a tiered early warning strategy, including: The pressure of the corresponding tensioning jack 13 is monitored by each pressure sensor 20. When a local pressure deviation > 5%, the corresponding tensioning jack 13 automatically decelerates until the pressure value of the corresponding tensioning jack 13 returns to normal. The strain value at each point is monitored by each of the fiber optic sensors 16. When a sudden change in strain value > 10% occurs, tensioning is paused and three-dimensional scanning is started. The tilt of the concrete tower cylinder 21 is monitored by the Beidou displacement monitoring instrument 11. When the tilt is greater than 0.1°, emergency pressure relief is carried out until the tilt returns to normal.

[0029] The method for calculating the tilt angle is as follows: θ=a×(F_left- F_right)+b×(T_top-T_bottom).

[0030] Taking a 120m high concrete tower as an example, the concrete tower 21 is composed of multiple segments; two Beidou displacement monitoring instruments 11 are symmetrically arranged on the top of the concrete tower 21; eight steel strands 22 are evenly arranged along the axial direction of the concrete tower 21, and the top of each steel strand 22 is fixed to the top of the concrete tower 21 by a top anchoring device 23. A tensioning jack 13 is provided at the bottom of each steel strand 22, and a displacement sensor 19 and a pressure sensor 20 are respectively provided on the tensioning jack 13; a force sensor 15 is provided on the steel strand 22 outside each working anchor 18, and a support plate 24 is provided below the force sensor 15. The tensioning jack 13 is fixedly connected to the support plate 24; the hydraulic pump station 14 is in master-slave control mode, including a master hydraulic pump station and multiple slave hydraulic pump stations connected to the master hydraulic pump station. Hydraulic pump stations are respectively set up one-to-one with the tensioning jacks 13 and connected to them through oil pipes; the temperature sensors 12 are evenly divided into two groups, with the two groups of temperature sensors 12 arranged vertically and alternately, and the number of temperature sensors 12 in each group corresponds to the number of steel strands 22; the fiber optic sensors 16 are evenly divided into five groups, with four fiber optic sensors 16 in each group, and the four fiber optic sensors 16 are evenly arranged along the circumference of the concrete tower cylinder 21; the intelligent control system 17 is set on the main hydraulic pump station and is equipped with a wireless communication module 25. The intelligent control system 17 stores the BIM model of the concrete tower cylinder 21, and the intelligent control system 17 communicates with the Beidou displacement monitor 11, the temperature sensors 12, the hydraulic pump station 14, the force sensor 15, the displacement sensor 19, the pressure sensor 20 and the fiber optic sensors 16 through the wireless communication module 25.

[0031] During tensioning, initial tensioning parameters are loaded into the BIM model for conflict detection. After conflict detection, graded coordinated tensioning begins. During the pre-tensioning stage, synchronous tensioning is performed at 10% of the design tension value using a ring-shaped symmetrical point group. The tensioning speed is controlled to ≤5mm / s, and the synchronization error is controlled to ≤2%, with abnormal state monitoring. During the main tensioning stage, prestressing tensioning employs dual control of pressure and elongation. The loading rate is dynamically adjusted based on strain feedback, controlling the synchronization error to ≤1.5%, and abnormal state monitoring continues. Once 100% of the design tension value is reached, the load-bearing stage begins. During the load-bearing stage, automatic prestress loss compensation is performed every 5 minutes, and abnormal state monitoring continues. The pressure is controlled and stabilized at ±0.3MPa. The abnormal state monitoring adopts a graded early warning strategy, including: monitoring the pressure of the corresponding tensioning jack 13 through each pressure sensor 20; when a local pressure deviation >5%, the corresponding tensioning jack 13 automatically decelerates until the pressure value of the corresponding tensioning jack 13 returns to normal; monitoring the strain value at each point through each fiber optic sensor 16; when a sudden change in strain value >10%, tensioning is paused and three-dimensional scanning is started; monitoring the tilt of the concrete tower cylinder 21 through the Beidou displacement monitor 11; when the tilt >0.1°, emergency pressure relief is performed until the tilt returns to normal.

[0032] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A prestressed intelligent tensioning system for hybrid tower wind turbines, characterized in that, The system includes a Beidou displacement monitor, a temperature sensor, tension jacks, a hydraulic pump station, a force sensor, a fiber optic sensor, and an intelligent control system. The Beidou displacement monitors are spaced apart at the top of the concrete tower. The temperature sensors are installed on the steel strands inside the concrete tower. The tension jacks are installed at the bottom of the steel strands and connected to the hydraulic pump station. The force sensors are installed on the steel strands outside each working anchor. Each tension jack is equipped with a displacement sensor and a pressure sensor. The fiber optic sensors are installed on the concrete tower. The intelligent control system is located on the hydraulic pump station and is communicatively connected to the Beidou displacement monitor, the temperature sensor, the hydraulic pump station, the force sensor, the displacement sensor, the pressure sensor, and the fiber optic sensor.

2. The intelligent prestressed tensioning system for hybrid tower wind turbines according to claim 1, characterized in that, The fiber optic sensors are evenly divided into multiple groups, and the multiple groups of fiber optic sensors are evenly arranged along the height direction of the concrete tower.

3. The intelligent prestressed tensioning system for hybrid tower wind turbines according to claim 2, characterized in that, The fiber optic sensors are evenly divided into five groups, with four fiber optic sensors in each group. The four fiber optic sensors are evenly arranged along the circumference of the concrete tower.

4. A dynamic control method for a prestressed intelligent tensioning system for a hybrid tower wind turbine, characterized in that, Includes the following steps: Step 1: First, install the Beidou displacement monitoring instrument and fiber optic sensor at the corresponding positions on the concrete tower cylinder. Then, install the temperature sensor, tensioning jack, and force sensor at the corresponding positions on the steel strands. Install the displacement sensor and pressure sensor on the tensioning jack. Next, connect the tensioning jack to the hydraulic pump station. Then, connect the Beidou displacement monitoring instrument, the temperature sensor, the hydraulic pump station, the force sensor, the displacement sensor, the pressure sensor, and the fiber optic sensor to the intelligent control system for communication. Step 2: Perform graded coordinated tensioning on the concrete tower cylinder, and carry out prestress loss compensation and abnormal state monitoring.

5. The dynamic control method for the prestressed intelligent tensioning system of the hybrid tower wind turbine according to claim 4, characterized in that, The hierarchical coordinated tensioning includes: Pre-tensioning stage: Synchronous tensioning of the annular symmetrical point group is carried out according to 10% of the design tension value, the synchronization error is controlled to be ≤2%, and abnormal conditions are monitored; The main tensioning stage: The prestressing tensioning adopts dual control of pressure value and elongation. The loading rate is dynamically adjusted according to strain feedback, the synchronization error is controlled to be ≤1.5%, and abnormal conditions are monitored. After reaching 100% of the design tension value, the load holding stage is entered. During the load-bearing stage: Automatic prestress loss compensation is performed at regular intervals, and abnormal conditions are monitored to control the pressure stabilization at ±0.3MPa.

6. The dynamic control method for the prestressed intelligent tensioning system of the hybrid tower wind turbine according to claim 5, characterized in that, The loading rate is dynamically adjusted based on strain feedback, and the calculation method for the loading rate is as follows: v=vθ×(1-|Δε_i / ε_avg|) Where Δε_i is the strain deviation at point i, and ε_avg is the mean strain.

7. The dynamic control method for the prestressed intelligent tensioning system of the hybrid tower wind turbine according to claim 5, characterized in that, The abnormal status monitoring adopts a tiered early warning strategy, including: The pressure of the corresponding tensioning jack is monitored by each pressure sensor. When a local pressure deviation is greater than 5%, the corresponding tensioning jack will automatically decelerate until the pressure value of the corresponding tensioning jack returns to normal. The strain value at each point is monitored by various fiber optic sensors. When a sudden change in strain value >10% occurs, tensioning is paused and three-dimensional scanning is initiated. The tilt of the concrete tower is monitored by a Beidou displacement monitoring instrument. When the tilt is greater than 0.1°, emergency pressure relief is carried out until the tilt returns to normal.

8. The dynamic control method for the intelligent prestressed tensioning system of the hybrid tower wind turbine according to claim 6, characterized in that, The method for calculating the tilt angle is as follows: θ=a×(F_left- F_right)+b×(T_top-T_bottom).

9. The dynamic control method for the prestressed intelligent tensioning system of the hybrid tower wind turbine according to claim 4, characterized in that, The prestress loss compensation is adjusted in a closed loop every 5 minutes, and its calculation method is as follows: Δσ_corr=k1×ΔT+k2×In(t)+k3×ε_creep Where k1 is the temperature loss coefficient, k2 is the time loss coefficient, and k3 is the creep coefficient.

Images