Method for calculating the operation parameters of a counterweight of a counterweight device for a communication system

Abstract

This invention discloses a method for calculating the operating parameters of a balance weight in a balancing device for a communication system. The spatial motion of the balance weight is simplified to a one-dimensional dynamic model of vertical motion, ignoring lateral offset and torsional effects. Specifically, the method includes the following steps: Step 1, initializing parameters and establishing an antenna screen model; Step 2, calculating the initial tension of the balance weight's traction rope; Step 3, dynamic iterative calculation. The method disclosed in this invention overcomes the limitations of traditional static balance calculations, focusing on revealing the kinematic mechanism of the balance weight under unsteady conditions, and achieving continuous quantification and dynamic analysis of the balance weight's displacement, velocity, and instantaneous acceleration throughout its entire stroke. It is simple in principle, technically feasible, and easy to apply, possessing strong versatility and engineering applicability.

Description

Technical Field

[0001] This invention belongs to the field of balance control technology for communication tower mast antenna curtain cable net structures, and specifically relates to a method for calculating the operating parameters of the counterweight of a balancing device for a communication system. Background Technology

[0002] Longwave and shortwave antennas typically require multiple tall support towers. The antenna cable net structure experiences significant tension under wind loads, which can impact the safety of the support towers. To ensure the safety of the support towers, medium to large-scale communication system antenna cable net structures are generally equipped with balancing devices to guarantee stable antenna operation under live loads, balanced stress distribution, and the safety of the support tower structure.

[0003] The antenna balancing device involved in this invention consists of a counterweight, a balancing rail, pulleys, etc., and is connected to the antenna curtain via an adjusting rope. Under wind load conditions, they interact and work together to automatically adjust the tension of the antenna curtain, ensuring the safety of the antenna system. The counterweight, as the core component of the balancing device, is used to achieve constant tension, adaptive sag, and stability of the antenna curtain cable net structure under the load of the supporting tower mast. When designing this balancing device, it is necessary to reasonably determine the vertical travel of the counterweight and pay attention to parameters such as speed and acceleration during its operation, ensuring the safety of the balancing device and the entire antenna curtain cable net structure while considering economic efficiency.

[0004] Traditional analysis methods for calculating the stroke of the counterweight in a balancing device only calculate the stroke of the counterweight when the antenna curtain cable net structure reaches static balance. This method has certain limitations, and the stroke is generally smaller than the actual required stroke. It does not analyze the full dynamic operation process of the counterweight and cannot fully reflect the operation process of the counterweight. Summary of the Invention

[0005] The technical problem to be solved by this invention is to provide a method for calculating the operating parameters of the balance hammer in a balancing device for a communication system, thereby realizing the calculation of the displacement, velocity and instantaneous acceleration of the balance hammer during operation, and providing a theoretical basis for the structural design, dynamic analysis and control strategy optimization of the balancing device.

[0006] The present invention adopts the following technical solution:

[0007] An improvement of the method for calculating the operating parameters of a balance weight in a balancing device for a communication system is that the spatial motion of the balance weight is simplified into a one-dimensional dynamic model of vertical motion, ignoring lateral offset and torsional effects. Specifically, the method includes the following steps:

[0008] Step 1: Initialize parameters and build the antenna canopy model:

[0009] Set the calculation time step Δt and establish the initial geometric model of the antenna curtain based on finite element analysis software;

[0010] Step 2, calculate the initial tension in the counterweight traction rope:

[0011] Static analysis was performed with the balancing device off to obtain the initial tension at each hanging point of the antenna screen. The tension at each hanging point was then converted into the initial tension of the traction rope above the counterweight based on the transmission ratio of the pulley system. ;

[0012] Step 3, Dynamic iterative calculation:

[0013] Utilizing the tension of the traction rope at the current moment Given the weight of the counterweight G, calculate the instantaneous acceleration of the counterweight at the current moment. The initial tension of the traction rope is ;

[0014] Based on the instantaneous acceleration of the counterweight at the current moment ,speed Given a time step Δt, calculate the velocity of the counterweight at the next moment. The initial velocity of the counterweight ;

[0015] Based on the instantaneous acceleration of the counterweight at the current moment ,speed Given a time step Δt, calculate the distance the counterweight rises from the current moment to the next moment, and update the cumulative displacement of the counterweight. The initial displacement of the counterweight ;

[0016] Based on the updated cumulative displacement of the counterweight In the geometric model of the antenna curtain, release the corresponding length of traction rope, update the coordinates and boundary conditions of the relevant nodes in the model, perform static analysis again to obtain the new tension at each hanging point of the antenna curtain, and convert the new tension at each hanging point into the traction rope tension at the next moment according to the transmission ratio of the pulley system. ;

[0017] Determine if the counterweight has reached a balanced and stationary state. If not, use the velocity of the next moment as the velocity of the current moment and repeat this step; if it has reached a balanced and stationary state, proceed to the next step.

[0018] Step 4, smooth the fitted data:

[0019] The data obtained in step 3 are fitted to generate smooth, continuous curves of displacement, velocity, and instantaneous acceleration against time.

[0020] Furthermore, in step 3, the instantaneous acceleration of the counterweight The calculation formula is:

[0021]

[0022] In the above formula, The mass of the counterweight.

[0023] Furthermore, in step 3, the counterweight velocity at the next moment... The calculation formula is:

[0024]

[0025] In the above formula, Δt is the time step.

[0026] Furthermore, in step 3, the cumulative displacement of the counterweight... The calculation formula is:

[0027]

[0028] In the above formula, This represents the cumulative displacement of the counterweight at the current moment.

[0029] Furthermore, in step 3, the condition for determining whether the counterweight has reached a balanced and static state is:

[0030] When a counterweight is suspended in the air, its velocity and instantaneous acceleration are close to zero; when the counterweight is placed on the ground, its cumulative displacement is close to zero.

[0031] Furthermore, in step 4, a multinomial regression algorithm is used to fit the data.

[0032] Furthermore, the maximum displacement, maximum velocity, and maximum instantaneous acceleration of the counterweight are extracted from the curve. If the maximum displacement exceeds the design stroke, the installation position of the limit device is re-optimized and adjusted, and the stiffness and damping parameters of the buffer device are re-optimized and adjusted based on the maximum velocity and maximum instantaneous acceleration.

[0033] The beneficial effects of this invention are:

[0034] The method disclosed in this invention breaks through the limitations of traditional static equilibrium calculations, focusing on revealing the kinematic mechanism of the balance weight under unsteady conditions, and realizing continuous quantification and dynamic analysis of the balance weight's displacement, velocity, and instantaneous acceleration throughout its entire stroke. It is simple in principle, technically feasible, and easy to apply, possessing strong versatility and engineering applicability.

[0035] The computational model used in this invention not only fits engineering practice better, but also allows for the quantitative solution of the dynamic response of the counterweight under unsteady conditions during the design phase. This reduces testing costs and improves R&D efficiency, providing data support for the structural and stroke design of the balancing device, the setting of limit devices, and the optimization of buffer strategies. It effectively improves the operational safety, stability, reliability, and control accuracy of the communication antenna system under complex conditions. Attached Figure Description

[0036] Figure 1 This is a flowchart illustrating the method of the present invention;

[0037] Figure 2 This is a schematic diagram of the arrangement of the balancing device in the antenna structure;

[0038] Figure 3 It is a graph showing the change of the counterweight displacement over time;

[0039] Figure 4 It is a graph showing the change of the counterweight's speed over time;

[0040] Figure 5 It is a graph showing the instantaneous acceleration of the counterweight as a function of time. Detailed Implementation

[0041] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0042] Example 1 discloses a method for calculating the operating parameters of a balance weight in a balancing device for a communication system. This method aims to solve the problem in existing technologies where static balance calculations of the balance weight's stroke fail to reflect the dynamic process and instantaneous extreme parameters. The method establishes a one-dimensional dynamic model, combines it with finite element static analysis, and constructs a real-time feedback mechanism between the balance weight's displacement and the tension of the traction rope. It iteratively calculates the dynamic displacement, velocity, and instantaneous acceleration parameters of the balance weight using discrete time steps, such as... Figure 1 As shown, the specific steps include the following:

[0043] The spatial motion of the counterweight is simplified into a one-dimensional dynamic model of motion along a single vertical direction, ignoring lateral offset and torsional effects.

[0044] Step 1: Initialize parameters and build the antenna canopy model:

[0045] Set the calculation time step Δt and establish the initial geometric model of the antenna curtain based on finite element analysis software;

[0046] Step 2, calculate the initial tension in the counterweight traction rope:

[0047] Static analysis was performed with the balancing device off (i.e., the counterweight in a static locked state) to obtain the initial tension at each hanging point of the antenna screen. The tension at each hanging point was then converted into the initial tension of the traction rope above the counterweight based on the transmission ratio of the pulley system. ;

[0048] Step 3, Dynamic iterative calculation:

[0049] In each time step iteration, the following sub-steps are executed sequentially:

[0050] Based on Newton's second law, using the tension in the traction rope at the current moment... Given the weight of the counterweight G, calculate the instantaneous acceleration of the counterweight at the current moment. The initial tension of the traction rope is ;

[0051] instantaneous acceleration of counterweight The calculation formula is:

[0052]

[0053] In the above formula, The mass of the counterweight.

[0054] Based on the instantaneous acceleration of the counterweight at the current moment ,speed and time step Δt (i.e. ), calculate the velocity of the counterweight at the next moment. The initial velocity of the counterweight ;

[0055] The velocity of the counterweight at the next moment The calculation formula is:

[0056]

[0057] In the above formula, Δt is the time step.

[0058] Based on the instantaneous acceleration of the counterweight at the current moment ,speed Given a time step Δt, calculate the distance the counterweight rises from the current moment to the next moment, and update the cumulative displacement of the counterweight. The initial displacement of the counterweight ;

[0059] Cumulative displacement of the counterweight The calculation formula is:

[0060]

[0061] In the above formula, This represents the cumulative displacement of the counterweight at the current moment.

[0062] Based on the updated cumulative displacement of the counterweight In the geometric model of the antenna curtain, release the corresponding length of traction rope, update the coordinates and boundary conditions of the relevant nodes in the model, perform static analysis again to obtain the new tension at each hanging point of the antenna curtain, and convert the new tension at each hanging point into the traction rope tension at the next moment according to the transmission ratio of the pulley system. ;

[0063] "Re-performing static analysis" includes: converting the cumulative displacement of the counterweight into the coordinate update of the corresponding node in the antenna curtain model, updating the boundary conditions of the model, and then using the finite element method to solve for the updated internal force distribution of the structure.

[0064] To determine whether a counterweight has reached a state of equilibrium and rest, the condition for determining whether a counterweight has reached a state of equilibrium and rest is:

[0065] When the counterweight is suspended in the air, its velocity and instantaneous acceleration both approach zero (i.e., it reaches a new static equilibrium state); when the counterweight is placed on the ground, its cumulative displacement approaches zero (i.e., the counterweight falls back to the ground).

[0066] If the target is not reached, the speed at the next moment will be used as the speed at the current moment, and this step will be repeated; if the target is reached, proceed to the next step.

[0067] Step 4, smooth the fitted data:

[0068] Import the discrete time series data (displacement, velocity, instantaneous acceleration) obtained from the iterative calculation in step 3 into the data processing module, and use the multinomial regression algorithm to fit the data to generate smooth continuous curves of displacement, velocity, and instantaneous acceleration against time.

[0069] Key characteristic parameters such as the maximum displacement, maximum velocity, and maximum instantaneous acceleration of the counterweight are extracted from the curve to facilitate engineering decisions.

[0070] (1) Stroke verification: Compare the calculated maximum displacement with the design stroke of the balancing device to determine whether there is a risk of overshooting.

[0071] (2) Limiting and buffering design: If the maximum displacement exceeds the design stroke, the installation position of the limiting device will be readjusted and the stiffness and damping parameters of the buffer device will be readjusted according to the maximum speed and the maximum instantaneous acceleration to absorb the impact energy when the counterweight hits the limiting device and ensure the safety of the antenna system.

[0072] In summary, the method of this invention establishes a one-dimensional vertical motion dynamic model of the counterweight, performs static analysis on the antenna curtain cable net structure using finite element analysis software, obtains the tension at each hanging point of the antenna curtain and converts it into the tension of the traction rope above the counterweight; then, it constructs a discrete-time iterative algorithm with displacement-tension coupling feedback, and simulates the dynamic operation of the counterweight under wind load by iteratively executing the steps of "calculating the instantaneous acceleration, velocity and displacement update of the counterweight" and "back-calculating the tension of the traction rope based on the boundary conditions of the displacement update model" until the counterweight reaches equilibrium; finally, it outputs the displacement, velocity and instantaneous acceleration data of the counterweight during operation and extracts the characteristic parameters required for design.

[0073] The following uses a communication tower mast antenna curtain balancing device as a specific application scenario. The method of this invention is used to calculate the displacement, velocity and instantaneous acceleration extreme values ​​of the counterweight during the unbalanced motion process under the action of sudden gust load. Based on this, the stroke of the counterweight is designed and the limit buffer design is optimized.

[0074] like Figure 2 As shown, the antenna structure includes four support towers: No. 1, 2, 3, and 4. Towers No. 3 and 4 are equipped with balancing devices. The mass of the counterweight at tower No. 3 is m3 = 39388 kg, and the mass of the counterweight at tower No. 4 is m4 = 30204 kg. The traction rope of the counterweight is connected to the antenna curtain cable net through a fixed pulley, meaning the transmission ratio of the pulley system is 1:1.

[0075] Step 1: Establish a dynamic model:

[0076] Ignoring lateral offset and torsional effects, the spatial motion of the counterweight is simplified to a one-dimensional particle dynamics model moving in the vertical direction.

[0077] Set the time step Δt = 0.1s, and the initial displacement... (Set the initial position as the origin), initial velocity (Assuming the counterweight is released from rest or suddenly unlocked from a locked state), the acceleration due to gravity g = 9.8 m / s². 2 ,

[0078] The counterweights have weights G3=mg=386kN and G4=mg=296kN.

[0079] Step 2, Solving for the initial state:

[0080] An initial geometric model of the antenna curtain cable net was established using the finite element analysis software ANSYS. A gust load of v=35m / s (simulating the instantaneous state after a sudden wind load) was applied with the counterweight in a static locked state. Static analysis was then performed on the antenna curtain cable net structure to obtain the tension F at each hanging point of the antenna curtain. 3-0 =472.99kN, F 4-0=418.59kN, based on the transmission ratio of the pulley system, the tension at each hanging point is converted into the initial tension of the traction rope above the counterweight. , .

[0081] Step 3, Dynamic Iterative Loop Calculation:

[0082] Assuming the counterweight is placed on the ground, the cycle terminates when the displacement of the counterweight approaches zero (i.e., the counterweight falls back to the ground). In each time step iteration, the following sub-steps are executed sequentially:

[0083] 1) Based on Newton's second law, utilize the tension of the traction rope at the current moment. Given the counterweight G, calculate the instantaneous acceleration at the current moment. :

[0084]

[0085]

[0086]

[0087] 2) Instantaneous acceleration based on the current moment ,speed and time step Δt (i.e. The instantaneous velocity at the next moment is calculated using the kinematic equations. ;

[0088]

[0089]

[0090]

[0091] 3) Instantaneous acceleration based on the current moment ,speed Given a time step Δt, calculate the counterweight from the current time. To the next moment The rising distance is used to update the cumulative displacement of the counterweight. ;

[0092]

[0093]

[0094]

[0095] 4) Accumulate displacement based on the updated counterweight Release the corresponding length of traction rope in the finite element antenna curtain model. , The coordinates and boundary conditions of the relevant nodes in the model are updated, and static analysis is performed again to obtain the new tension at each hanging point. This tension is then converted into the traction rope tension at the next moment based on the pulley transmission ratio. ( , );

[0096] 5) Determine whether the balance weight has reached a balanced and static state. If not, take the state of the next moment as the state of the current moment and return to execute sub-step 1); if it has reached a balanced and static state, end the iteration.

[0097] In this example, the iteration stopped when the counterweight rose to its maximum displacement and then fell back to its initial position, and the calculation result met the design requirements.

[0098] Step 4, Data Smoothing and Feature Extraction:

[0099] Import the discrete time series data (displacement, velocity, instantaneous acceleration) obtained by iterative calculation at 108 time steps into the MATLAB data processing module.

[0100] The data were fitted using sixth-order polynomial regression to generate smooth, continuous displacement-time, velocity-time, and instantaneous acceleration-time curves, as shown below. Figure 3 , 4 As shown in Figure 5, the key characteristic parameter, the maximum upward displacement of the counterweight, is extracted from the curve. and Maximum instantaneous velocity and Maximum instantaneous acceleration and .

[0101] The maximum upward displacement of the balance weight calculated using traditional static methods is and The maximum displacement of the counterweight obtained by the method of this invention is much smaller. Therefore, the stroke of the balancing device designed according to the traditional method is too small, and the counterweight will have a large impact on the limiting device, which may cause damage in severe cases.

[0102] Step 5, Engineering Application and Optimization Design:

[0103] Utilizing the feature parameters extracted in step four for engineering decision-making:

[0104] 1) Stroke verification: Compare the calculated maximum upward displacement with the design stroke of the balancing device to determine whether there is a risk of overshooting.

[0105] Assuming the maximum allowable stroke in this design is as follows: and All of these values ​​are less than the maximum stroke calculated above. Therefore, a suitable buffer needs to be designed to absorb the impact energy.

[0106] 2) Limit and buffer design: Since the maximum upward displacement of the counterweight exceeds the design value, the design stroke... and The velocity and instantaneous acceleration of the counterweight at the corresponding moments are respectively , , , The impact energies generated by the counterweights are as follows:

[0107]

[0108] Based on the above calculation results, design the stiffness and damping parameters of the buffer device to absorb the impact energy when the counterweight strikes the limiting device and ensure the safety of the antenna system. If there is no suitable one or the cost is too high, the stroke of the counterweight needs to be redesigned.

Claims

1. A method for calculating the operating parameters of a balance weight in a balancing device for a communication system, characterized in that: The spatial motion of the counterweight is simplified into a one-dimensional dynamic model of vertical motion, ignoring lateral offset and torsional effects. The specific steps include: Step 1: Initialize parameters and build the antenna canopy model: Set the calculation time step Δt and establish the initial geometric model of the antenna curtain based on finite element analysis software; Step 2, calculate the initial tension in the counterweight traction rope: Static analysis was performed with the balancing device off to obtain the initial tension at each hanging point of the antenna screen. The tension at each hanging point was then converted into the initial tension of the traction rope above the counterweight based on the transmission ratio of the pulley system. ; Step 3, Dynamic iterative calculation: Utilizing the tension of the traction rope at the current moment Given the weight of the counterweight G, calculate the instantaneous acceleration of the counterweight at the current moment. The initial tension of the traction rope is ; Based on the instantaneous acceleration of the counterweight at the current moment ,speed Given a time step Δt, calculate the velocity of the counterweight at the next moment. The initial velocity of the counterweight ; Based on the instantaneous acceleration of the counterweight at the current moment ,speed Given a time step Δt, calculate the distance the counterweight rises from the current moment to the next moment, and update the cumulative displacement of the counterweight. The initial displacement of the counterweight ; Based on the updated cumulative displacement of the counterweight In the geometric model of the antenna curtain, release the corresponding length of traction rope, update the coordinates and boundary conditions of the relevant nodes in the model, perform static analysis again to obtain the new tension at each hanging point of the antenna curtain, and convert the new tension at each hanging point into the traction rope tension at the next moment according to the transmission ratio of the pulley system. ; Determine if the counterweight has reached a balanced and stationary state. If not, use the velocity of the next moment as the velocity of the current moment and repeat this step; if it has reached a balanced and stationary state, proceed to the next step. Step 4, smooth the fitted data: The data obtained in step 3 are fitted to generate smooth, continuous curves of displacement, velocity, and instantaneous acceleration against time.

2. The method for calculating the operating parameters of the balance weight of the balancing device for a communication system according to claim 1, characterized in that, In step 3, the instantaneous acceleration of the counterweight The calculation formula is: In the above formula, The mass of the counterweight.

3. The method for calculating the operating parameters of the balance weight of the balancing device for a communication system according to claim 1, characterized in that, In step 3, the velocity of the counterweight at the next moment. The calculation formula is: In the above formula, Δt is the time step.

4. The method for calculating the operating parameters of the balance weight of the balancing device for a communication system according to claim 1, characterized in that, In step 3, the cumulative displacement of the counterweight The calculation formula is: In the above formula, This represents the cumulative displacement of the counterweight at the current moment.

5. The method for calculating the operating parameters of the balance weight of the balancing device for a communication system according to claim 1, characterized in that, In step 3, the condition for determining whether the counterweight has reached a balanced and static state is: When a counterweight is suspended in the air, its velocity and instantaneous acceleration are close to zero; when the counterweight is placed on the ground, its cumulative displacement is close to zero.

6. The method for calculating the operating parameters of the balance weight of the balancing device for a communication system according to claim 1, characterized in that, In step 4, a multinomial regression algorithm is used to fit the data.

7. The method for calculating the operating parameters of the balance weight of the balancing device for a communication system according to claim 1, characterized in that: Extract the maximum displacement, maximum velocity, and maximum instantaneous acceleration of the counterweight from the curve. If the maximum displacement exceeds the design stroke, readjust the installation position of the limit device and readjust the stiffness and damping parameters of the buffer device based on the maximum velocity and maximum instantaneous acceleration.

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