Method for adjusting the tension of the tension machine outlet when the transmission line tension pay-off board passes through the corner tower

Abstract

The present invention proposes a method for adjusting the outlet tension of a tension machine for a transmission line tension pay-off board passing a corner tower, including stretch calculation, steering pulley pre-tilt angle calculation, torque balance equation of the board rotation axis, mathematical model of tension machine outlet tension and board inclination angle, and adjustment strategy for tension machine outlet tension of the board passing a corner tower. The steering pulley pre-tilt angle is calculated by stretch calculation and the angle of rotation of the corner tower; the torque balance equation of the board rotation axis is obtained by force analysis of the board, thereby obtaining the relationship between the vertical component of the tension of the four sub-conductors on the board and the board inclination angle; the mathematical model of tension machine outlet tension and board inclination angle is obtained by the conductor oblique parabola suspension curve equation and stretch calculation; thereby, a tension machine outlet tension adjustment strategy for the four sub-conductors of the board passing a corner tower is proposed.

Description

Technical Field

[0001] The invention belongs to the technical field of tension pay-out construction of power transmission lines, and in particular relates to a method for adjusting the outlet tension of a tension machine for tension pay-out of power transmission lines passing through a corner tower. Background Art

[0002] Tension pay-off as a new type of pay-off method has become the most important link in the construction process of power transmission lines. Whether the plank can pass through the pay-off pulley smoothly during the pay-off process is related to the safety of the entire pay-off process.

[0003] The current research on the mechanical model of transmission line tension release mainly focuses on the calculation of overhead line extension. In the process of transmission line tension release, multiple monitoring personnel are required to track the entire release process, observe the changes in the posture of the board, report the status of the board to the commander of the control center through the walkie-talkie, and guide the tension field release personnel to adjust the tension machine outlet tension and then adjust the posture of the board. Therefore, a large number of staff members need to cooperate with each other to complete the entire release process, which seriously affects the construction efficiency.

[0004] At present, the relative posture of the board and the slider in the tension wire-laying mechanical model is rarely studied, and the flipping posture of the board has not been systematically studied. Although there is a way to monitor the posture of the board through wireless video, it is necessary to set up a camera on each tower and transmit a large amount of data, which is not suitable for construction sites of various terrains. There is also an existing technology that uses ADAMS to establish a numerical simulation model of the wire-laying system, studies the changes in the posture of the board, and proposes corresponding adjustment strategies. However, due to the limitations of the ADAMS software itself, it can only be simulated under small gear spacing, small height difference and limited wire-laying gear number, so it cannot provide practical guidance for the posture adjustment of the board during the entire wire-laying process. Summary of the invention

[0005] In order to fill the gap in the prior art, the present invention provides a method for adjusting the tension of a tension machine outlet of a transmission line tension pay-off board passing a corner tower. In the absence of a monitoring personnel in the pay-off section, the outlet tension of the four sub-conductors of the tension machine is controlled to make the board inclination angle equal to the pre-inclination angle of the steering pulley, thereby ensuring that the board passes the steering pulley smoothly. This can effectively solve the problem that in the current tension pay-off process, a monitoring personnel is required to monitor the board posture and guide the tension field pay-off personnel to adjust the board posture by adjusting the tension machine outlet tension.

[0006] The invention includes stretching calculation, calculation of pre-tilt angle of steering pulley, torque balance equation of the rotating shaft of the walking board, mathematical model of tension machine outlet tension and walking board inclination angle, and adjustment strategy of tension machine outlet tension of the walking board passing through the corner tower. The pre-tilt angle of the steering pulley is calculated by stretching calculation and the degree of rotation of the corner tower; then the torque balance equation of the rotating shaft of the walking board is obtained by force analysis of the walking board, thereby obtaining the relationship between the vertical component of the tension of the four sub-conductors on the walking board and the inclination angle of the walking board; through the inclined parabola suspension curve equation of the conductor and stretching calculation, the mathematical model of tension machine outlet tension and walking board inclination angle is obtained; thus, a tension machine outlet tension adjustment strategy for the four sub-conductors of the walking board passing through the corner tower is proposed. The invention can automatically calculate the tension machine outlet tension of the walking board passing through the corner tower according to the position of the dangerous point, the gear spacing and height difference of the wire laying gear, and the degree of rotation of the corner tower, so as to adjust the inclination angle of the walking board by controlling the tension machine outlet tension without monitoring personnel, so that the walking board can pass the steering pulley smoothly, and has very high engineering application value.

[0007] The specific technical solutions are as follows:

[0008] A method for adjusting the tension of a tension machine outlet for a transmission line tension pay-off board passing through a corner tower, characterized in that it comprises the following steps:

[0009] Step S1: Determine the parameters of the conductor, traction rope, wire-laying pulley and walking board; determine the location of the dangerous point and the minimum safe distance in the wire-laying section; determine the gear spacing, height difference and line turning angle information of each wire-laying gear;

[0010] Step S2: Calculate the horizontal tension H of the wire in the control gear by using a simplified parabola formula according to the location of the danger point and the corresponding minimum safety distance requirement;

[0011] Step S3: According to the horizontal tension H of the control gear, combined with the gear spacing and height difference of each pay-off gear, the outlet tension T of the tension machine is calculated. Tj , take the maximum outlet tension of the entire pay-off segment (T Tj ) max As the control value of the tension machine outlet tension T T ;

[0012] Step S4: The tension machine outlet tension T calculated in step S3 T The axial tension of the conductor on both sides of the wire-laying pulley of each tower in the wire-laying section is determined by combining the height difference and height difference angle of the wire-laying section, and then the horizontal tension H of the conductor in each section of the wire-laying section is calculated using the oblique parabola model. i ;

[0013] Step S5: Using the horizontal tension H of the wire at each pay-off level obtained in step S4 i Calculate the vertical load W borne by the tower wire-laying pulley i ;

[0014] When the vertical load W i Greater than the rated load T of the pulley Q When the load is halved, a double pulley is hung on the tower. At this time, the vertical load of the conductor borne by a single pulley is halved.

[0015] Step S6: Utilize the horizontal tension H of the wire at the pay-off station obtained in step S4 i Calculate the envelope angle φ of the conductor on the wire-laying pulley a And judge φ a size;

[0016] When φ a When the angle is greater than 30°, a double pulley is hung on the tower, and the vertical load of the conductor borne by a single pulley is halved.

[0017] Step S7: According to the known angle of rotation of the corner tower α and the horizontal tension H of the conductor at each pay-off level calculated in step S4, i Calculate the horizontal angular force of the conductor on the steering pulley, and then calculate the pre-tilt angle η of the steering pulley in combination with the vertical load of the conductor calculated in step S5;

[0018] Step S8: before the walking board passes the turning pulley, a dynamic analysis is performed on it to obtain a torque balance equation of the walking board rotating around the rotation axis when the walking board rotates, and a mathematical model of the vertical component of the tension of each sub-conductor and the inclination angle of the walking board is obtained;

[0019] Step S9: Based on the mathematical model obtained in step S9, a mathematical model of the tension machine outlet tension and the board inclination angle is obtained through the overhead line inclined parabola suspension curve equation and stretching calculation;

[0020] Step S10: adjusting the tension of the tension machine outlet of the four sub-conductors passing through the corner tower according to the mathematical model obtained in step S9.

[0021] Furthermore, in step S2, the horizontal tension H of the wire in the control gear is calculated as shown in formula (4):

[0022]

[0023] Among them, ω is the deadweight per unit length of the conductor; s is the horizontal distance between the control point and the adjacent tower; l is the spacing of the wire laying gear where the dangerous point is located; N is the height difference between the control point and the conductor hanging point of the adjacent tower; Y is the safe distance of the control point; β is the height difference angle of the control gear; when the height difference of the control gear is negative, the "±" in the formula is taken as "+", otherwise, it is taken as "-".

[0024] Further, in step S3, the tension machine outlet tension T corresponding to each control gear in the pay-off gear is Tj for:

[0025]

[0026]

[0027] Then the control value of the tension machine outlet tension is:

[0028] T T =(T Tj ) max (7)

[0029] Among them, H j is the horizontal tension of the wire at the jth gear, i.e. the control gear; ε is the friction coefficient between the wire and the pulley; K j is the tension coefficient of the pay-off gear, which is the ratio of the pay-off gear horizontal tension to the tension machine outlet tension; (T Tj ) max is the maximum outlet tension of the tension machine; T D Design breaking force of the conductor; h j is the height difference of the jth gear. When the suspension point on the traction side is higher than the suspension point on the tension side, h i The “±” in front of the number should be replaced by “+”, otherwise, it should be replaced by “-”.

[0030] Furthermore, the specific calculation process of step S4 is:

[0031] Step S41: Calculate the axial tension of the wire on both sides of each hanging point:

[0032] T Zi =T′ Zi-1 ±ωh i (8)

[0033] T′ Zi =T Zi ε (9)

[0034] Among them, T Zi is the axial tension of the conductor on the tension side of the i-th tower hanging point; T′ Zi is the axial tension of the conductor on the traction side of the i-th tower hanging point. When i=1, T′ Zi-1 is the maximum outlet tension of the tension machine T T ; When the traction side suspension point is higher than the tension side suspension point, h i The “±” before is replaced by “+”, otherwise, it is replaced by “-”;

[0035] Step S42: Calculate the horizontal tension H of the wire at each pay-off level i for:

[0036]

[0037] in, is the average axial tension of the conductor; l i It is the gear spacing of the i-th gear of the pay-off gear.

[0038] Further, in step S5, the vertical load of the wire borne by the pulley is calculated as follows:

[0039]

[0040] Among them, l i and l i+1 h is the distance between the front and rear sides of the tower where the pulley is located; i and h i+1 It is the height difference between the wire suspension points on the front and rear sides of the tower where the pulley is located. When the suspension point of the adjacent tower is lower, the tower is marked with a "+" sign, otherwise it is marked with a "-" sign.

[0041] Furthermore, in step S6, the envelope angle is calculated as shown in formula (12):

[0042]

[0043]

[0044]

[0045] Among them, α is the rotation angle of the corner tower; θ A θ is the rope hanging angle at the front side of the pay-out block, i.e. the tension side; B H is the rope hanging angle at the rear side of the pay-off block, i.e. the traction side; i H is the horizontal tension of the i-th pay-off gear; i+1 It is the horizontal tension of the i+1th pay-off gear.

[0046] Furthermore, in step S7, the specific process of calculation is:

[0047] Step S71: Calculate the horizontal force on the steering pulley:

[0048]

[0049] Step S72: Calculate the vertical force of the steering pulley as:

[0050]

[0051] Step S73: Calculate the pre-tilt angle of the steering pulley as:

[0052]

[0053] Among them, W H is the deadweight of the steering pulley; N is the number of steering pulleys; k is the impact coefficient.

[0054] Preferably, in this step, in order for the walking board to pass the steering pulley smoothly, it is necessary to take pre-tilt measures for the steering pulley on the corner tower, and the pre-tilt angle of the steering pulley is calculated by analyzing the forces on the steering pulley in the horizontal and vertical directions.

[0055] Further, step S8 specifically includes the following steps:

[0056] During the process of pulling and releasing the wire, only the pulling force of the four sub-wires, the pulling force of the traction rope and the gravity of the board are considered. When the pulling force of the four sub-wires on the board is unequal, the board will rotate around the central axis of its plane. Due to the action of the balance hammer, the board will maintain balance after rotating to a certain angle, thereby obtaining the moment balance equation of the board's rotation axis;

[0057] Step S81: Assume that the walking board and the balance weight on the walking board always maintain a vertical relationship, and the pitch angle of the walking board during the traction process is zero; the torque balance equation of the walking board rotation axis is:

[0058] F1'·2L+F2'·L+m1g·x1=F3'·L+F4'·2L (18)

[0059] Among them, F1' is the vertical component of the tension F1 of the No. 1 sub-conductor; F2' is the vertical component of the tension F2 of the No. 2 sub-conductor; F3' is the vertical component of the tension F3 of the No. 3 sub-conductor; F4' is the vertical component of the tension F4 of the No. 4 sub-conductor; m1 is the weight of the walking board balance hammer; L is the force arm of the tension, and x1 is the force arm of the weight of the balance hammer;

[0060] Step S82: Combined with formula (18), the relationship between the vertical component of the sub-conductor tension and the inclination angle of the walking board is obtained as follows:

[0061]

[0062] Wherein, D is the length of the walking board; d is the length of the counterweight; λ is the rotation angle of the walking board.

[0063] Furthermore, step S9 specifically includes the following steps:

[0064] The entire overhead line connected to the board is regarded as a parabola, and the relationship between the horizontal component and the vertical component of the tension of the four sub-conductors on the board is obtained by differentiating the overhead line oblique parabola suspension curve equation, and the relationship between the horizontal component of the tension of the four sub-conductors on the board and the board inclination angle is obtained by combining; finally, the tension of the tension machine outlet corresponding to the horizontal component of the conductor tension is deduced through the wire stretching calculation, thereby obtaining the mathematical model of the tension of each sub-conductor and the board inclination angle;

[0065] In the example of the present invention, by making the inclination angle of the walking board equal to the pre-inclination angle of the steering pulley, that is, λ=η, the outlet tension of the tension machine of the four sub-conductors at this time can be obtained;

[0066] Step S91: construct the equation of the overhead line oblique parabola suspension curve:

[0067]

[0068] Among them, when the suspension point on the traction side of the pay-off gear is higher than the suspension point on the tension side, the "±" in the formula is "+", otherwise, it is "-";

[0069] Step S92: By taking the derivative of the overhead line parabola suspension curve equation (20), the relationship between the horizontal component and the vertical component of the sub-conductor tension is obtained as follows:

[0070]

[0071] Among them, H0 is the horizontal component of the tension of the sub-conductor; l is the spacing of the wire-laying gear where the walking board is located; β is the height difference angle;

[0072] Step S93: The relationship between the horizontal component of the tension of the four sub-conductors in the pay-off gear and the inclination angle of the board is obtained from formula (21):

[0073]

[0074] Among them, H1 is the horizontal component of the tension of the No. 1 sub-conductor; H2 is the horizontal component of the tension of the No. 2 sub-conductor; H3 is the horizontal component of the tension of the No. 3 sub-conductor; H4 is the horizontal component of the tension of the No. 4 sub-conductor;

[0075] Step S94: The outlet tension of the tension machine is deduced from the horizontal tension of the pay-off gear by formula (5) and formula (6), and the mathematical model of the outlet tension of the four-wire tension machine and the inclination angle of the board is obtained:

[0076]

[0077] Among them, T1 is the tension machine outlet tension of the No. 1 sub-conductor; T2 is the tension machine outlet tension of the No. 2 sub-conductor; T3 is the tension machine outlet tension of the No. 3 sub-conductor; T4 is the tension machine outlet tension of the No. 4 sub-conductor, K i is the tension coefficient of the pay-off gear; when the suspension point on the traction side is higher than the suspension point on the tension side, the “±” in the formula takes “+”, otherwise, takes “-”.

[0078] Further, in step S10:

[0079] Under the premise that the initial outlet tension of the tension machine of the four sub-conductors is equal and the minimum safe distance between the conductor and the important span is guaranteed, when adjusting the values ​​of T1, T2, T3 and T4, it is ensured that they cannot be less than the initial outlet tension of the tension machine of the four sub-conductors. The optional adjustment strategies include:

[0080] Strategy 1: Keep the values ​​of T2 and T3 unchanged as the initial outlet tension, and adjust the values ​​of T4 and T1 by using the difference between T4 and T1 calculated by formula (23). When keeping T1 unchanged, adjust the inclination angle of the board by adjusting the value of T4.

[0081] Strategy 2: Keep the values ​​of T2 and T3 unchanged as the initial outlet tension, and adjust the values ​​of T4 and T1 by using the difference between T4 and T1 calculated by formula (23). When keeping T4 unchanged, adjust the inclination angle of the board by adjusting the value of T1.

[0082] Strategy 3: Keep the values ​​of T2 and T3 unchanged as the initial outlet tension, adjust the values ​​of T4 and T1 by using the difference between T4 and T1 calculated by formula (23), and adjust the inclination angle of the board by adjusting the values ​​of T4 and T1 at the same time;

[0083] Strategy 4: Set the 0% to 50% of the initial outlet tension of the tension machine as the difference adjustment range of T2 and T3, and adjust the values ​​of T2 and T3 accordingly. Then use the difference between T4 and T1 calculated by formula (23) to adjust the values ​​of T4 and T1. When keeping T1 unchanged, adjust the inclination angle of the board by adjusting the value of T4.

[0084] Strategy 5: Set the difference adjustment range of T2 and T3 from 0% to 50% of the initial outlet tension of the tension machine to adjust the values ​​of T2 and T3, and then use the difference between T4 and T1 calculated by formula (23) to adjust the values ​​of T4 and T1. When keeping T4 unchanged, adjust the inclination angle of the board by adjusting the value of T1.

[0085] Strategy 6: Set the difference adjustment range of T2 and T3 to 0% to 50% of the initial outlet tension of the tension machine, and adjust the values ​​of T2 and T3 accordingly. Then use the difference between T4 and T1 calculated by formula (23) to adjust the values ​​of T4 and T1. The inclination angle of the board is adjusted by adjusting the values ​​of T4 and T1 at the same time.

[0086] The present invention and its preferred solution include stretching calculation, steering pulley pre-tilt angle calculation, torque balance equation of the board rotation axis, mathematical model of tension machine outlet tension and board tilt angle, and adjustment strategy of tension machine outlet tension of the board passing through the corner tower. The steering pulley pre-tilt angle is calculated by stretching calculation and the degree of rotation of the corner tower; then the torque balance equation of the board rotation axis is obtained by force analysis of the board, thereby obtaining the relationship between the vertical component of the tension of the four sub-conductors on the board and the board tilt angle; through the conductor oblique parabola suspension curve equation and stretching calculation, the mathematical model of tension machine outlet tension and board tilt angle is obtained; thereby, a tension machine outlet tension adjustment strategy for the four sub-conductors of the board passing through the corner tower is proposed. The tension machine outlet tension of the board passing through the corner tower can be automatically calculated according to the position of the dangerous point, the gear spacing and height difference of the wire release gear, and the degree of rotation of the corner tower, so as to adjust the inclination angle of the board by controlling the tension machine outlet tension without monitoring personnel, so that the board can pass the steering pulley smoothly, which has very high engineering application value.

[0087] In the scheme, the horizontal tension of the conductor in each wire-laying gear and the vertical load of the conductor borne by the wire-laying pulley on each tower are calculated according to the position of the dangerous point, the gear spacing and height difference of each wire-laying gear. When the vertical load of the conductor borne by the wire-laying pulley is greater than the rated load of the wire-laying pulley or the envelope angle of the conductor on the pulley is greater than 30°, a double pulley is hung on the tower. At this time, the vertical load of the conductor borne by the single pulley on the tower is half of the original one.

[0088] The horizontal force on the steering pulley is calculated based on the known turning angle of the turning tower and the calculated horizontal tension of the conductor at each pay-off stage, and the pre-tilt angle of the steering pulley is calculated based on the calculated vertical load of the conductor on the steering pulley.

[0089] To facilitate analysis and simplify calculations, during the deployment of the conductors, only the tension of the four sub-conductors, the traction of the traction rope and the gravity of the conductor are considered. When the tension of the four sub-conductors on the conductor are unequal, the conductor will rotate around the central axis of its plane. Therefore, the torque balance equation of the rotation axis of the conductor is established when the conductor rotates, and the mathematical model of the vertical component of the tension of each sub-conductor and the inclination angle of the conductor is obtained, which is convenient for proposing an adjustment strategy for the inclination angle of the conductor.

[0090] The entire overhead line connected to the board is regarded as a parabola, and the equation of the overhead line oblique parabola suspension curve is derived to obtain the relationship between the horizontal component and the vertical component of the tension of the four sub-conductors on the board. According to the mathematical model of the vertical component of the tension of the four sub-conductors on the board and the inclination angle of the board obtained by calculation, the relationship between the horizontal component of the tension of the four sub-conductors on the board and the inclination angle of the board is obtained; finally, the tension machine outlet tension corresponding to the horizontal component of the tension of the four sub-conductors is deduced through stretching calculation, thereby obtaining the mathematical model of the tension machine outlet tension of the four sub-conductors and the inclination angle of the board.

[0091] When the board passes the corner tower, it is hoped that the inclination angle of the board is consistent with the pre-inclination angle of the steering pulley. According to the mathematical model of the pre-inclination angle of the steering pulley obtained in claim 3 and the calculated outlet tension of the tension machine of each sub-conductor and the inclination angle of the board, it can be known that when the inclination angle of the board is the same as the pre-inclination angle of the steering pulley, the outlet tension of the tension machine of the four sub-conductors can be obtained under the condition of known inclination angle of the board. Therefore, a strategy for adjusting the outlet tension of the tension machine of the four sub-conductors when the board passes the corner tower is proposed.

[0092] Its beneficial effects include: being able to automatically calculate the tension of the tension machine outlet of the walking board passing the corner tower according to the location of the dangerous point, the gear spacing and height difference of the wire-laying gear, and the turning angle of the corner tower, and proposing a tension adjustment strategy for the tension machine outlet of the walking board passing the corner tower, so that the inclination angle of the walking board can be adjusted by controlling the tension machine outlet tension in the absence of monitoring personnel, so that the walking board can pass the turning pulley smoothly, and it has high practical value. BRIEF DESCRIPTION OF THE DRAWINGS

[0093] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments:

[0094] Figure 1 The figure is a flow chart of the model calculation method according to an embodiment of the present invention.

[0095] Figure 2 The front view of a one-to-four-walking platform established for an embodiment of the present invention.

[0096] Figure 3 A front view of a one-to-four-walking platform constructed for an embodiment of the present invention.

[0097] Figure 4 The left view of the one-to-four-walking platform established in accordance with an embodiment of the present invention.

[0098] In the figure: 1-walking board, 2-balance hammer, 3-No. 1 sub-conductor, 4-No. 2 sub-conductor, 5-No. 3 sub-conductor, 6-No. 4 sub-conductor, 7-traction rope, 8-rotating shaft. DETAILED DESCRIPTION

[0099] In order to make the features and advantages of this patent more obvious and easy to understand, the following embodiments are specifically described in detail as follows:

[0100] like Figure 1 As shown, the present embodiment provides a flow chart of the tension adjustment strategy for the transmission line tension release board passing through the corner tower outlet, as shown in FIG. Figure 2-Figure 4 As shown, the conductor deployment method adopts one-to-four synchronous deployment, and the specific steps of implementation are as follows:

[0101] (1) Determine the parameters of the conductor, traction rope 7, wire-laying pulley and walking board 1; determine the location of the dangerous point and the minimum safe distance in the wire-laying section; determine the span, height difference and line turning angle information of each wire-laying section; determine the number of traction wires m=4. In this example, the overhead line is regarded as an ideal flexible cable chain without rigidity and the specific load of the overhead line is evenly distributed along the inclined span.

[0102] (2) Before the line construction, it is necessary to survey the dangerous points along the road. According to the location of the dangerous points and the minimum safety distance requirements, the horizontal tension H of the conductor in the control range is calculated using a simplified parabola formula as shown in formula (4):

[0103]

[0104] Among them, ω is the deadweight per unit length of the conductor, N / m; s is the horizontal distance between the control point and the adjacent tower, m; l is the spacing of the wire laying gear where the dangerous point is located, m; N is the height difference between the control point and the conductor hanging point adjacent to the tower, m; Y is the safety distance of the control point, m; β is the height difference angle of the control gear; when the height difference of the control gear is negative, the "±" in the formula is "+", otherwise, it is "-".

[0105] (3) According to the horizontal tension H of the control gear, combined with the gear spacing and height difference of each pay-off gear, the outlet tension T of the tension machine is deduced. Tj Since there may be multiple dangerous points in a line-laying section, corresponding to multiple outlet tensions, the maximum outlet tension (T Tj ) max As the control value of the tension machine outlet tension T T . The tension machine outlet tension T corresponding to each control gear in the pay-off gear Tj for:

[0106]

[0107]

[0108] Then the control value of the tension machine outlet tension is:

[0109] T T =(T Tj ) max (7)

[0110] Among them, Hj is the horizontal tension of the wire in the jth gear (control gear); ε is the friction coefficient between the wire and the pulley, which is generally 1.012~1.015; K j is the tension coefficient of the pay-off gear, which is the ratio of the pay-off gear horizontal tension to the tension machine outlet tension; (T Tj ) max is the maximum outlet tension of the tension machine, N; T D Design breaking force of the conductor; h j is the height difference of the jth gear, m, when the traction side suspension point is higher than the tension side suspension point, h i The “±” in front of the number should be replaced by “+”, otherwise, it should be replaced by “-”.

[0111] (4) Before calculating the horizontal tension of the conductor at each laying-out step, it is necessary to calculate the axial tension of the conductor on both sides of the tower hanging point, and then calculate the horizontal tension H of the conductor at each laying-out step. i .

[0112] a. The axial tension of the conductor on both sides of each hanging point is:

[0113] T Zi =T′ Zi-1 ±ωh i (8)

[0114] T′ Zi =T Zi ε (9)

[0115] Among them, T Zi is the axial tension of the conductor on the tension side of the i-th tower hanging point, N; T′ Zi is the axial tension of the conductor on the traction side of the i-th tower hanging point, N. When i=1, T′ Zi-1 is the maximum outlet tension of the tension machine T T , N; when the traction side suspension point is higher than the tension side suspension point, h i The “±” in front of the number should be replaced by “+”, otherwise, it should be replaced by “-”.

[0116] b. Horizontal tension H of the conductor at each pay-off level i for:

[0117]

[0118] in, is the average axial tension of the conductor; l i is the gear distance of the i-th gear of the pay-off gear;

[0119] (5) When the conductor passes through the pulley on the tower, it will generate a vertical load on the pulley. The size of the vertical load determines whether to hang a double pulley. When the vertical load of the conductor borne by the pulley is greater than the rated load T of the pulley,Q When the vertical load of the conductor borne by the single pulley is halved, a double pulley is required to be hung on the tower. The vertical load of the conductor borne by the pulley is calculated as follows:

[0120]

[0121] Among them, l i and l i+1 h is the distance between the front and rear sides of the tower where the pulley is located; i and h i+1 It is the height difference between the wire suspension points on the front and rear sides of the tower where the pulley is located. When the suspension point of the adjacent tower is lower, the tower is marked with a "+" sign, otherwise it is marked with a "-" sign.

[0122] (6) The size of the conductor's envelope angle on the pulley also determines whether to hang a double pulley. When the envelope angle is greater than 30°, a double pulley must be hung on the tower. At this time, the vertical load of the conductor borne by a single pulley is halved. The envelope angle is calculated as shown in formula (12):

[0123]

[0124]

[0125]

[0126] Among them, α is the rotation angle of the corner tower; θ A θ is the rope hanging angle at the front side (tension side) of the pay-out block; B H is the rope hanging angle at the rear side (traction side) of the pay-out block; i H is the horizontal tension of the i-th pay-off gear; i+1 It is the horizontal tension of the (i+1)th pay-off gear.

[0127] (7) In order to allow the walking board to pass the steering pulley smoothly, it is necessary to take pre-tilt measures for the steering pulley on the corner tower. By analyzing the forces on the steering pulley in the horizontal and vertical directions, the pre-tilt angle of the steering pulley can be calculated.

[0128] a. The horizontal direction of the steering pulley is:

[0129]

[0130] b. The vertical force on the steering pulley is:

[0131]

[0132] c. The pre-tilt angle of the steering pulley is:

[0133]

[0134] Among them, W H is the deadweight of the steering pulley, N; N is the number of steering pulleys; k is the impact coefficient, and k is generally taken as 1.2 according to safety regulations.

[0135] (8) In order to study the changes in the posture of the walking board during the wire pulling and releasing process, the force analysis of the walking board is carried out. The main view of the one-pulling four-walking board is as follows Figure 2 As shown, only the tension of the four sub-conductors, the traction of the traction rope and the gravity of the board are considered. When the tension of the four sub-conductors on the board is unequal, the board will rotate around the central axis of its plane. Due to the action of the balance hammer 2, the board will maintain balance after rotating to a certain angle. Therefore, the torque balance equation of the board rotation axis 8 is established, and the mathematical model of the vertical component of the tension of each sub-conductor of the board and the inclination angle is obtained.

[0136] a. For the convenience of analysis and calculation, it is assumed that the walking board and the balance hammer on the walking board always maintain a vertical relationship, and the pitch angle of the walking board during the traction process is zero. The front view of one traction four walking boards is as follows Figure 3 As shown. Through the dynamic analysis of the walking board, it can be known that since the line of action of the traction force on the walking board intersects with the rotation axis of the walking board, the torque of the traction force on the rotation axis is zero and has no effect on the rotation of the walking board. The rotation of the walking board is only related to the vertical component of the sub-conductor tension and the gravity of the balance hammer. The left view of the one-traction four-walking board is shown as follows Figure 4 As shown. The moment balance equation of the walking plate rotation axis is:

[0137] F1'·2L+F2'·L+m1g·x1=F3'·L+F4'·2L (18)

[0138] Among them, F1' is the vertical component of the tension F1 of the No. 1 sub-conductor 3, N; F2' is the vertical component of the tension F2 of the No. 2 sub-conductor 4, N; F3' is the vertical component of the tension F3 of the No. 3 sub-conductor 5, N; F4' is the vertical component of the tension F4 of the No. 4 sub-conductor 6, N; m1 is the weight of the walking board balance hammer, Kg; L is the force arm of the tension, cm, and x1 is the force arm of the balance hammer gravity, cm.

[0139] b. By Figure 4 Knowable Combined with formula (18), the relationship between the vertical component of the sub-conductor tension and the inclination angle of the walking board is obtained as follows:

[0140]

[0141] Wherein, D is the length of the walking board, m; d is the length of the counterweight, m; λ is the rotation angle of the walking board, °.

[0142] (9) The entire overhead line connected to the board is regarded as a parabola, and the equation of the overhead line oblique parabola suspension curve is derived to obtain the relationship between the horizontal component and the vertical component of the tension of the four sub-conductors on the board, and the mathematical model of the vertical component of the tension of each sub-conductor and the board inclination angle is obtained according to formula (19), and the relationship between the horizontal component of the tension of the four sub-conductors on the board and the board inclination angle is obtained. Finally, the tension of the tension machine outlet corresponding to the horizontal component of the conductor tension is derived through the wire stretching calculation, thereby obtaining the mathematical model of the tension of each sub-conductor and the board inclination angle.

[0143] a. The equation of the overhead line oblique parabola suspension curve is:

[0144]

[0145] Among them, when the suspension point on the traction side of the pay-off gear is higher than the suspension point on the tension side, the "±" in the formula is taken as "+", otherwise, it is taken as "-".

[0146] b. By taking the derivative of the overhead line parabola suspension curve equation (20), the relationship between the horizontal component and the vertical component of the sub-conductor tension can be obtained as follows:

[0147]

[0148] Among them, H0 is the horizontal component of the sub-conductor tension, N; l is the spacing of the wire-laying gear where the walking board is located, m; β is the height difference angle.

[0149] c. From formula (21), we can get the relationship between the horizontal component of the tension of the four sub-conductors in the wire-laying section and the inclination angle of the board:

[0150]

[0151] Among them, H1 is the horizontal component of the tension of the No. 1 sub-conductor, N; H2 is the horizontal component of the tension of the No. 2 sub-conductor, N; H3 is the horizontal component of the tension of the No. 3 sub-conductor, N; H4 is the horizontal component of the tension of the No. 4 sub-conductor, N.

[0152] d. Formula (5) and formula (6) can be used to deduce the tension at the outlet of the tension machine from the horizontal tension of the pay-off gear, and the mathematical model of the outlet tension of the four-wire tension machine and the inclination angle of the board is obtained as follows:

[0153]

[0154] Among them, T1 is the outlet tension of the tension machine of the No. 1 sub-conductor, N; T2 is the outlet tension of the tension machine of the No. 2 sub-conductor, N; T3 is the outlet tension of the tension machine of the No. 3 sub-conductor, N; T4 is the outlet tension of the tension machine of the No. 4 sub-conductor, N.

[0155] (10) When the walking board passes the corner tower, it is hoped that the inclination angle of the walking board is consistent with the pre-inclination angle of the steering pulley. Formula (23) can be used to obtain the outlet tension of the tension machine of the four sub-conductors under the condition of known inclination angle of the walking board. Based on this, a strategy for adjusting the outlet tension of the tension machine of the four sub-conductors when the walking board passes the corner tower is proposed.

[0156] Since the initial outlet tension of the tension machine of the four sub-conductors is equal, and in order to ensure the minimum safe distance between the conductor and the important span, when adjusting the values ​​of T1, T2, T3 and T4, it must be ensured that they are not less than the initial outlet tension. Therefore, there are several strategies for adjusting the outlet tension of the tension machine of the four sub-conductors:

[0157] Strategy 1: Keep the values ​​of T2 and T3 unchanged as the initial outlet tension, and use the difference between T4 and T1 calculated by formula (23) to adjust the values ​​of T4 and T1. When keeping T1 unchanged, adjust the inclination angle of the board by adjusting the value of T4.

[0158] Strategy 2: Keep the values ​​of T2 and T3 unchanged as the initial outlet tension, and use the difference between T4 and T1 calculated by formula (23) to adjust the values ​​of T4 and T1. When keeping T4 unchanged, adjust the inclination angle of the board by adjusting the value of T1.

[0159] Strategy 3: Keep the values ​​of T2 and T3 unchanged as the initial outlet tension, use the difference between T4 and T1 calculated by formula (23) to adjust the values ​​of T4 and T1, and adjust the inclination angle of the board by adjusting the values ​​of T4 and T1 at the same time.

[0160] Strategy 4: Set the difference adjustment range of T2 and T3 from 0% to 50% of the initial outlet tension of the tension machine to adjust the values ​​of T2 and T3, and then use the difference between T4 and T1 calculated by formula (23) to adjust the values ​​of T4 and T1. When keeping T1 unchanged, adjust the inclination angle of the board by adjusting the value of T4.

[0161] Strategy 5: Set the difference adjustment range of T2 and T3 from 0% to 50% of the initial outlet tension of the tension machine to adjust the values ​​of T2 and T3, and then use the difference between T4 and T1 calculated by formula (23) to adjust the values ​​of T4 and T1. When keeping T4 unchanged, adjust the inclination angle of the board by adjusting the value of T1.

[0162] Strategy 6: Set the difference adjustment range of T2 and T3 to 0% to 50% of the initial outlet tension of the tension machine, so as to adjust the values ​​of T2 and T3, and then use the difference between T4 and T1 calculated by formula (23) to adjust the values ​​of T4 and T1. By adjusting the values ​​of T4 and T1 at the same time, the inclination angle of the board can be adjusted.

[0163] This patent is not limited to the above-mentioned optimal implementation method. Anyone can derive other forms of transmission line tension pay-out and tension machine outlet tension adjustment methods passing through corner towers under the inspiration of this patent. All equivalent changes and modifications made within the scope of the patent application of the present invention shall fall within the scope of this patent.

Claims

1. A method for adjusting the tension of a tension machine outlet for a transmission line tension pay-off board passing through a corner tower, characterized in that: The following steps are involved: Step S1: Determine the parameters of the conductor, traction rope, wire-laying pulley and walking board; Determine the location of dangerous points and the minimum safe distance within the line-laying section; determine the span, height difference and line turning angle information of each line-laying section; Step S2: Calculate the horizontal tension H of the wire in the control gear by using a simplified parabola formula according to the location of the danger point and the corresponding minimum safety distance requirement; Step S3: According to the horizontal tension H of the control gear, combined with the gear spacing and height difference of each pay-off gear, the outlet tension T of the tension machine is calculated. Tj , take the maximum outlet tension of the entire pay-off segment (T Tj ) max As the control value of the tension machine outlet tension T T ; Step S4: The tension machine outlet tension T calculated in step S3 T The axial tension of the conductor on both sides of the wire-laying pulley of each tower in the wire-laying section is determined by combining the height difference and height difference angle of the wire-laying section, and then the horizontal tension H of the conductor in each section of the wire-laying section is calculated using the inclined parabola model. i ; Step S5: Using the horizontal tension H of the wire at each pay-off level obtained in step S4 i Calculate the vertical load W borne by the tower wire-laying pulley i ; When the vertical load W i Greater than the rated load T of the pulley Q When the load is halved, a double pulley is hung on the tower. At this time, the vertical load of the conductor borne by a single pulley is halved. Step S6: Utilize the horizontal tension H of the wire at the pay-off station obtained in step S4 i Calculate the envelope angle φ of the conductor on the wire-laying pulley a And judge φ a size; When φ a When the angle is greater than 30°, a double pulley is hung on the tower, and the vertical load of the conductor borne by a single pulley is halved. Step S7: According to the known angle of rotation of the corner tower α and the horizontal tension H of the conductor at each pay-off level calculated in step S4, i Calculate the horizontal angular force of the conductor on the steering pulley, and then calculate the pre-tilt angle η of the steering pulley in combination with the vertical load of the conductor calculated in step S5; Step S8: before the walking board passes the turning pulley, a dynamic analysis is performed on it to obtain a torque balance equation of the walking board rotating around the rotation axis when the walking board rotates, and a mathematical model of the vertical component of the tension of each sub-conductor and the inclination angle of the walking board is obtained; Step S9: Based on the mathematical model obtained in step S9, a mathematical model of the tension machine outlet tension and the board inclination angle is obtained through the overhead line inclined parabola suspension curve equation and stretching calculation; Step S10: According to the mathematical model obtained in step S9, the board is moved through the tension machine outlet of the four sub-conductors of the corner tower. Tension adjustment; In step S2, the horizontal tension H of the conductor in the control gear is calculated as shown in formula (4): Where ω is the deadweight per unit length of the conductor; s is the horizontal distance between the control point and the adjacent tower; l is the dangerous point The span of the wire laying station; N is the height difference between the control point and the wire hanging point of the adjacent tower; Y is the safety distance of the control point; β is the height difference angle of the control gear; when the height difference of the control gear is negative, the "±" in the formula is "+", otherwise, it is "-"; In step S3, the tension machine outlet tension T corresponding to each control gear in the pay-off gear is Tj for: Then the control value of the tension machine outlet tension is: T T =(T Tj ) max (7) Among them, H j is the horizontal tension of the wire at the jth gear, i.e. the control gear; ε is the friction coefficient between the wire and the pulley; K j is the tension coefficient of the pay-off gear, which is the ratio of the pay-off gear horizontal tension to the tension machine outlet tension; (T Tj ) max Maximum tension machine Outlet tension; T D Design breaking force of the conductor; h j is the height difference of the jth gear. When the traction side suspension point is higher than the tension side suspension point When hanging point, h i The "±" in front is replaced by "+", otherwise, it is replaced by "-"; The specific calculation process of step S4 is: Step S41: Calculate the axial tension of the wire on both sides of each hanging point: T Zi =T Z ' i-1 ±ωh i (8) T Z ' i =T Zi ε (9) Among them, T Zi is the axial tension of the conductor on the tension side of the i-th tower hanging point; T Z ' i The wire is at the hanging point of the i-th tower Axial tension on the traction side, when i = 1, T Z ' i-1 is the maximum outlet tension of the tension machine T T ; When the traction side suspension point is higher than the tension When the force side suspension point is i The "±" in front is replaced by "+", otherwise, it is replaced by "-"; Step S42: Calculate the horizontal tension H of the wire at each pay-off level i for: in, is the average axial tension of the conductor; l i is the gear distance of the i-th gear of the pay-off gear; In step S5, the vertical load of the wire borne by the pulley is calculated as follows: Among them, l i and l i+1 h is the distance between the front and rear sides of the tower where the pulley is located; i and h i+1 It is the height difference between the wire suspension points on the front and rear sides of the tower where the pulley is located. When the suspension point of the adjacent tower is lower, the tower is marked with a "+" sign, otherwise it is marked with a "-" sign; In step S6, the envelope angle is calculated as shown in formula (12): Among them, α is the rotation angle of the corner tower; θ A θ is the rope hanging angle at the front side of the pay-out block, i.e. the tension side; B H is the rope hanging angle at the rear side of the pay-off block, i.e. the traction side; i H is the horizontal tension of the i-th pay-off gear; i+1 is the horizontal tension of the i+1th pay-off gear; In step S7, the specific process of calculation is: Step S71: Calculate the horizontal force on the steering pulley: Step S72: Calculate the vertical force of the steering pulley as: Step S73: Calculate the pre-tilt angle of the steering pulley as: Among them, W H is the deadweight of the steering pulley; N is the number of steering pulleys; k is the impact coefficient; Step S8 specifically includes the following steps: Step S81: Assume that the walking board and the balance weight on the walking board always maintain a vertical relationship, and the walking board pitches during the traction process The angle is zero; the torque balance equation of the walking plate rotation axis is: F1'·2L+F2'·L+m1g·x1=F3'·L+F4'·2L (18) Among them, F1' is the vertical component of the tension F1 of the No. 1 sub-conductor; F2' is the vertical component of the tension F2 of the No. 2 sub-conductor; F3' is the vertical component of the tension F3 of the No. 3 sub-conductor; F4' is the vertical component of the tension F4 of the No. 4 sub-conductor; m1 is the balance of the board The weight of the hammer; L is the arm of the pulling force, and x1 is the arm of the weight of the counterweight; Step S82: Combined with formula (18), the vertical component of the sub-conductor tension is obtained: The relationship with the inclination angle of the walking board is: Where D is the length of the walking board; d is the length of the counterweight; λ is the rotation angle of the walking board; Step S9 specifically includes the following steps: Step S91: construct the equation of the overhead line oblique parabola suspension curve: Among them, when the suspension point on the traction side of the pay-off gear is higher than the suspension point on the tension side, the "±" in the formula is "+", otherwise, it is "-"; Step S92: Obtain the level of the sub-conductor tension by taking the derivative of the overhead line parabola suspension curve equation (20) The relationship between the vertical component and the vertical component is: Among them, H0 is the horizontal component of the tension of the sub-conductor; l is the spacing of the wire-laying gear where the walking board is located; β is the height difference angle; Step S93: The relationship between the horizontal component of the tension of the four sub-conductors in the pay-off gear and the inclination angle of the board is obtained from formula (21): Among them, H1 is the horizontal component of the tension of the No. 1 sub-conductor; H2 is the horizontal component of the tension of the No. 2 sub-conductor; H3 is the horizontal component of the tension of the No. 3 sub-conductor; H4 is the horizontal component of the tension of the No. 4 sub-conductor; Step S94: The outlet tension of the tension machine is deduced from the horizontal tension of the pay-off gear by formula (5) and formula (6), and the mathematical model of the outlet tension of the four-wire tension machine and the inclination angle of the board is obtained: Among them, T1 is the tension machine outlet tension of the No. 1 sub-conductor; T2 is the tension machine outlet tension of the No. 2 sub-conductor; T3 is the tension machine outlet tension of the No. 3 sub-conductor; T4 is the tension machine outlet tension of the No. 4 sub-conductor; K i is the tension coefficient of the pay-off gear; when the suspension point on the traction side is higher than the suspension point on the tension side, the "±" in the formula is "+", otherwise, it is "-"; In step S10: Under the premise that the initial outlet tension of the tension machine of the four sub-conductors is equal and the minimum safe distance between the conductor and the important span is guaranteed, when adjusting the values ​​of T1, T2, T3 and T4, it is ensured that they cannot be less than the initial outlet tension of the tension machine of the four sub-conductors. The optional adjustment strategies include: Strategy 1: Keep the values ​​of T2 and T3 unchanged as the initial outlet tension, and adjust the values ​​of T4 and T1 by using the difference between T4 and T1 calculated by formula (23). When keeping T1 unchanged, adjust the inclination angle of the board by adjusting the value of T4. Strategy 2: Keep the values ​​of T2 and T3 unchanged as the initial outlet tension, and adjust the values ​​of T4 and T1 by using the difference between T4 and T1 calculated by formula (23). When keeping T4 unchanged, adjust the inclination angle of the board by adjusting the value of T1. Strategy 3: Keep the values ​​of T2 and T3 unchanged as the initial outlet tension, adjust the values ​​of T4 and T1 by using the difference between T4 and T1 calculated by formula (23), and adjust the inclination angle of the board by adjusting the values ​​of T4 and T1 at the same time; Strategy 4: Set the 0% to 50% of the initial outlet tension of the tension machine as the difference adjustment range of T2 and T3, and adjust the values ​​of T2 and T3 accordingly. Then use the difference between T4 and T1 calculated by formula (23) to adjust the values ​​of T4 and T1. When keeping T1 unchanged, adjust the inclination angle of the board by adjusting the value of T4. Strategy 5: Set the difference adjustment range of T2 and T3 from 0% to 50% of the initial outlet tension of the tension machine to adjust the values ​​of T2 and T3, and then use the difference between T4 and T1 calculated by formula (23) to adjust the values ​​of T4 and T1. When keeping T4 unchanged, adjust the inclination angle of the board by adjusting the value of T1. Strategy 6: Set the difference adjustment range of T2 and T3 to 0% to 50% of the initial outlet tension of the tension machine, and adjust the values ​​of T2 and T3 accordingly. Then use the difference between T4 and T1 calculated by formula (23) to adjust the values ​​of T4 and T1. The inclination angle of the board is adjusted by adjusting the values ​​of T4 and T1 at the same time.

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