A method for balancing and coordinating the tension of steel wire ropes in a double-rope winding hoisting system

Abstract

The present invention discloses a coordinated control method for wire rope tension balance of a double-rope winding hoisting system, which relates to the technical field of material conveying and hoisting, including establishing a dynamic model of a double-rope winding hoisting system according to the coupled vibration between the wire rope and the hoisting container, wherein the double-rope winding hoisting system includes uncertain parameters and unknown interference forces; based on the uncertain parameters and the unknown interference forces, taking wire rope tension balance control and lifting container longitudinal vibration suppression as control targets, an adaptive robust boundary controller for wire rope tension balance is formed; the adaptive robust controller is applied to the double-rope winding hoisting system, and a control strategy is implemented to keep the wire rope tension balanced and effectively suppress the longitudinal vibration of the lifting container. The present invention effectively solves the problems of wire rope tension imbalance and vibration in traditional hoisting systems by constructing a multi-coordinate system dynamic model and an adaptive robust boundary controller.

Description

Technical Field

[0001] The invention relates to the technical field of material conveying and lifting, in particular to a method for balancing and coordinating the tension of steel wire ropes in a double-rope winding lifting system. Background Art

[0002] The double-rope winding hoisting system, with its unique double-rope winding design, significantly improves the conveying efficiency and stability of material conveying equipment, and at the same time shows strong adaptability. Whether it is vertical or inclined conveying, it can easily meet the conveying needs of various bulk, block and powder materials. The system not only has a large carrying capacity and can carry heavy loads in a small space, but also achieves energy saving and environmental protection through variable frequency speed regulation technology, reduces energy consumption, and is widely used in many fields such as the mining industry, construction industry, and metallurgical industry.

[0003] However, the double-rope winding lifting system uses two steel wire ropes to lift a container at the same time. During the lifting process, the lifting steel wire rope and the lifting container will produce undesirable longitudinal vibrations. At the same time, in the actual lifting system, there will be manufacturing or installation deviations in the drum. The two steel wire ropes will also produce different elastic deformations due to their own manufacturing errors and different degrees of wear. In addition, the possible skipping and sliding of the rope will cause the elongation of the two steel wire ropes to be different. In the presence of a rigid tank channel, since it has a strong constraint on the lifting container, the lifting container is always kept horizontal. Therefore, the elongation of the steel wire rope is different, which will cause a tension difference in the steel wire rope. When the tension difference is too large, it will not only increase the friction between the container and the tank channel, but also increase the fatigue damage of the steel wire rope, affecting its service life, and even causing serious accidents such as stuck tanks and falling tanks.

[0004] Based on these potential risks, the present invention proposes a coordinated control method for wire rope tension balance of a double-rope winding hoisting system to achieve wire rope tension balance and container vibration suppression in the double-rope winding hoisting system, thereby ensuring safe and stable operation of the hoisting system. Summary of the invention

[0005] In view of the problems of unbalanced wire rope tension, container vibration and possible safety hazards in the existing double-rope winding lifting system, the present invention is proposed.

[0006] Therefore, the problem to be solved by the present invention is how to effectively achieve tension balance control of the wire rope in the double-rope winding lifting system and suppress the vibration of the lifting container, thereby ensuring the safety and stability of the lifting system.

[0007] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0008] In the first aspect, an embodiment of the present invention provides a method for coordinated control of wire rope tension balance in a double-rope winding lifting system, which includes establishing a dynamic model of the double-rope winding lifting system according to the coupled vibration between the wire rope and the lifting container, wherein the double-rope winding lifting system includes uncertain parameters and unknown interference forces; based on the uncertain parameters and the unknown interference forces, an adaptive robust boundary controller for wire rope tension balance is formed with wire rope tension balance control and longitudinal vibration suppression of the lifting container as control targets; the adaptive robust controller is applied to the double-rope winding lifting system, and a control strategy is implemented to keep the wire rope tension balanced and effectively suppress the longitudinal vibration of the lifting container.

[0009] As a preferred solution of the wire rope tension balance coordinated control method of the double-rope winding lifting system of the present invention, the method of constructing the dynamic model is to describe the system movement by setting a fixed coordinate system and a follower coordinate system, wherein the fixed coordinate system represents the macroscopic lifting and lowering movement of the system, and the follower coordinate system represents the vibration movement of each component of the system; define the parameters of the system movement, wherein the parameters include the total lifting height L, the lifting speed v, the lifting acceleration a and the lifting wire rope length l; analyze the vibration characteristics according to the parameters, record the longitudinal vibration displacement u(x,t) of the particle at the spatial position x of the vertical lifting wire rope at time t, and calculate the dynamic tension F of this particle d (x, t) is expressed as the sum of the quasi-static tension T(x, t) and the elastic force EAε(x, t), and the specific formula is as follows:

[0010] F d (x, t) = T (x, t) + EAε (x, t)

[0011] Among them, EA is the tensile stiffness of the wire rope, ε is the positive strain, and it represents the partial derivative of the longitudinal vibration displacement u(x, t) with respect to the spatial position x.

[0012] As a preferred solution of the wire rope tension balance coordination control method of the double-rope winding lifting system of the present invention, it also includes: according to the dynamic tension F d (x, t), comprehensively consider the kinetic energy, elastic potential energy and gravitational potential energy of the two steel wire ropes, the kinetic energy and gravitational potential energy of the two floating sheaves, and the kinetic energy and elastic potential energy of the lifting container; at the same time, consider the damping force of the two steel wire ropes, the damping of the lifting container, the damping of the floating sheave and the virtual work done by the exciting force exerted by the floating sheave to analyze the energy consumption items; based on Hamilton's principle, a dynamic model is constructed through various kinetic energies, elastic potential energies and virtual work; based on the dynamic model described in the dynamic model, the variational theory and the integration by parts method are used to obtain the overall dynamic model of the double-rope winding lifting system.

[0013] As a preferred solution of the wire rope tension balance coordinated control method of the double-rope winding hoisting system of the present invention, the dynamic model includes overall kinetic energy, overall potential energy and virtual work; the specific formula of the overall dynamic model is as follows:

[0014]

[0015]

[0016] Where, ρ is the linear density of the lifting wire rope, EA is the tensile stiffness of the wire rope, m a To improve the quality of the container and its load, m T is the mass of the floating sheave and the piston rod of the hydraulic cylinder, l is the length of the lifting wire rope, c ir To increase the longitudinal damping coefficient of the wire rope, c ic To increase the longitudinal damping coefficient at the container, c is is the damping coefficient at the floating sheave, F i (t) is the exciting force applied by the floating sheave to the wire rope, F i (t) is the exciting force applied to the wire rope by the floating sheave.

[0017] As a preferred solution of the wire rope tension balance coordination control method of the double-rope winding lifting system of the present invention, the specific formula of the overall kinetic energy is as follows:

[0018]

[0019] Among them, E k is the total kinetic energy, l(t) is the length of the lifting wire rope, v(t) is the lifting speed, x is the spatial position of the lifting wire rope, t is the time, u i (x, t) is the longitudinal vibration displacement of the i-th wire rope at the spatial position x and time t.

[0020] The specific formula of the overall potential energy is as follows:

[0021]

[0022] Among them, E p is the total potential energy, T i (x, t) is the lateral vibration displacement of the i-th wire rope at the spatial position x and time t.

[0023] The specific formula of the virtual work is as follows:

[0024]

[0025] Among them, δW is virtual work, c ir To increase the longitudinal damping coefficient of the wire rope, c icTo increase the longitudinal damping coefficient at the container, c is is the damping coefficient at the floating sheave, F i (t) is the exciting force applied to the wire rope by the floating sheave.

[0026] As a preferred solution of the coordinated control method for wire rope tension balance of the double-rope winding hoisting system of the present invention, wherein: based on the uncertain parameters and the unknown interference force, with wire rope tension balance control and lifting container longitudinal vibration suppression as control targets, an adaptive robust boundary controller for wire rope tension balance is formed, including: installing a tension sensor at the connection between the two wire ropes and the lifting container to obtain the tension H1 and tension H2 at the connection; calculating the deviation according to the tension measurement value, the specific formula is as follows:

[0027] ω f (t) = H1-H2;

[0028] Based on the overall kinetic energy, the overall potential energy and the tension deviation, an adaptive robust boundary controller is set to construct a Lyapunov function. The specific formula is as follows:

[0029] V(t)=α z V1(t)+β z V2(t)

[0030]

[0031] Among them, v(t) is the lifting speed, α z and β z is the positive definite weight coefficient, V1(t) is the rate of increase of the overall kinetic energy and overall potential energy, and V2(t) is the rate of increase of the tension deviation.

[0032] As a preferred solution of the wire rope tension balance coordinated control method of the double-rope winding hoisting system of the present invention, it also includes: defining the damping coefficient of the hoisting container, the load mass change and the wire rope line density difference as the uncertain parameters of the double-rope winding hoisting system θ = [c 1c c 2c m a ρ] Τ , the estimated vector is And a bounded estimate is made for the unknown interference force; based on the estimation of the uncertain parameters and the estimation error of the unknown interference force, the Lyapunov function is redefined, and the control law and the adaptive law are designed; based on the control law and the adaptive law, the Lyapunov stability theory is used to make the container vibration displacement and the wire rope tension difference converge to zero, thereby achieving wire rope tension balance control and lifting container longitudinal vibration suppression.

[0033] As a preferred solution of the wire rope tension balance coordinated control method of the double-rope winding lifting system of the present invention, the specific formulas of the control law and the adaptive law are as follows:

[0034]

[0035] Among them, F1 is the control law of overall kinetic energy and overall potential energy, and F2 is the control law of tension deviation. is the adaptive law of total kinetic energy and total potential energy, is the adaptive law of the ith wire rope with tension deviation, ui'(x,t) is the longitudinal vibration displacement of the ith wire rope at spatial position x and time t after coordinated control, d i (t) is the unknown disturbance force, N1 and N2 are the dynamic characteristics of the double-rope winding lifting system, is the interference upper bound D i The estimated value of k l1 , k r1 , k l2 , k r2 , k l3 and k r3 is the control parameter.

[0036] In a second aspect, an embodiment of the present invention provides a computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: when the computer program instructions are executed by the processor, the steps of the wire rope tension balance and coordination control method of a double-rope winding lifting system as described in the first aspect of the present invention are implemented.

[0037] In a third aspect, an embodiment of the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein: when the computer program instructions are executed by a processor, the steps of the method for coordinated control of wire rope tension balance of a double-rope winding lifting system as described in the first aspect of the present invention are implemented.

[0038] The beneficial effects of the present invention are as follows: the present invention effectively solves the problems of unbalanced wire rope tension and vibration in the traditional lifting system by constructing a multi-coordinate system dynamic model and an adaptive robust boundary controller; introduces a fixed coordinate system and a following coordinate system, comprehensively considers the system's kinetic energy, potential energy and damping characteristics, and combines real-time monitoring with a tension sensor to achieve accurate compensation for the system's uncertain parameters and unknown interference forces; the control law and adaptive law designed through the Lyapunov stability theory can not only make the wire rope tension dynamically balanced, but also effectively suppress the longitudinal vibration of the lifting container, significantly improve the stability, accuracy and reliability of the double-rope lifting system, and provide a new theoretical method and technical path for the intelligent control of complex engineering systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. Among them:

[0040] Figure 1 This is a flow chart of the wire rope tension balance and coordination control method of the double-rope winding lifting system in Example 1.

[0041] Figure 2 This is a schematic diagram of a double-rope winding type lifting system of Example 1, which is a method for balancing and coordinating the tension of steel wire ropes in a double-rope winding type lifting system.

[0042] Figure 3 These are the reference curves for the lifting heights of the two winches in the method for coordinated control of the wire rope tension balance of a double-rope winding lifting system in Example 2.

[0043] Figure 4 This is the wire rope tension with deviation in drum winding of the wire rope tension balance and coordination control method of the double-rope winding hoisting system in Example 2.

[0044] Figure 5 Example 2 is the wire rope tension under PID control of the wire rope tension balance and coordinated control method of the double-rope winding lifting system.

[0045] Figure 6 The wire rope tension under the controller proposed in the wire rope tension balance and coordinated control method of the double-rope winding lifting system in Example 2.

[0046] Figure 7 It is the tension difference between the two steel wire ropes under different control algorithms of the steel wire rope tension balance coordination control method of the double-rope winding lifting system in Example 2.

[0047] Figure 8 This is the uncontrolled vibration acceleration of the two steel wire ropes in the steel wire rope tension balance coordinated control method of the double-rope winding hoisting system in Example 2.

[0048] Fig. 9 It is the vibration acceleration of the two steel wire ropes under the control of the steel wire rope tension balance coordination control method of the double-rope winding lifting system in Example 2.

[0049] Fig.10 Example 2 is a proposed method for controlling the tension balance of the wire ropes in a double-rope winding hoisting system, and controls the vibration acceleration of the two wire ropes.

[0050] Fig.11It is the vibration displacement of the wire rope 1 under different control algorithms of the wire rope tension balance coordinated control method of the double-rope winding lifting system in Example 2.

[0051] Fig.12 It is the vibration displacement of the wire rope 2 under different control algorithms of the wire rope tension balance coordination control method of the double-rope winding lifting system in Example 2. DETAILED DESCRIPTION

[0052] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0053] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0054] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0055] Example 1

[0056] Reference Figure 1-2 , which is the first embodiment of the present invention, provides a method for balancing and coordinating the tension of a steel wire rope in a double-rope winding lifting system, comprising:

[0057] S1: According to the coupled vibration between the wire rope and the lifting container, a dynamic model of a double-rope winding lifting system is established, wherein the double-rope winding lifting system includes uncertain parameters and unknown interference forces.

[0058] Specifically, the method for constructing the dynamic model is to describe the system motion by setting a fixed coordinate system and a following coordinate system, wherein the fixed coordinate system represents the macroscopic lifting motion of the system, and the following coordinate system represents the vibration motion of each component of the system; define the parameters of the system motion, wherein the parameters include the total lifting height L, the lifting speed v, the lifting acceleration a, and the lifting wire rope length l; analyze the vibration characteristics according to the parameters, record the longitudinal vibration displacement u(x,t) of the particle at the spatial position x of the vertical lifting wire rope at time t, and calculate the dynamic tension F of this particle d (x, t) is expressed as the sum of the quasi-static tension T(x, t) and the elastic force EAε(x, t), and the specific formula is as follows:

[0059] F d(x, t) = T (x, t) + EAε (x, t)

[0060] Among them, EA is the tensile stiffness of the wire rope, ε is the positive strain, and it represents the partial derivative of the longitudinal vibration displacement u(x, t) with respect to the spatial position x.

[0061] Furthermore, according to the dynamic tension F d (x, t), comprehensively consider the kinetic energy, elastic potential energy and gravitational potential energy of the two steel wire ropes, the kinetic energy and gravitational potential energy of the two floating sheaves, and the kinetic energy and elastic potential energy of the lifting container; at the same time, consider the damping force of the two steel wire ropes, the damping of the lifting container, the damping of the floating sheave and the virtual work done by the exciting force exerted by the floating sheave to analyze the energy consumption items; based on Hamilton's principle, a dynamic model is constructed through various kinetic energies, elastic potential energies and virtual work; the dynamic model includes total kinetic energy, total potential energy and virtual work.

[0062] Furthermore, the specific formula for the total kinetic energy is as follows:

[0063]

[0064] Among them, E k is the total kinetic energy, l(t) is the length of the lifting wire rope, v(t) is the lifting speed, x is the spatial position of the lifting wire rope, t is the time, u i (x, t) is the longitudinal vibration displacement of the i-th wire rope at the spatial position x and time t.

[0065] Specifically, the specific formula for the overall potential energy is as follows:

[0066]

[0067] Among them, E p is the total potential energy, T i (x, t) is the lateral vibration displacement of the i-th wire rope at the spatial position x and time t.

[0068] Furthermore, the specific formula of virtual work is as follows:

[0069]

[0070] Among them, δW is virtual work, c ir To increase the longitudinal damping coefficient of the wire rope, c ic To increase the longitudinal damping coefficient at the container, c is is the damping coefficient at the floating sheave, F i (t) is the exciting force applied to the wire rope by the floating sheave.

[0071] Furthermore, based on the dynamic model, the overall dynamic model of the double-rope winding lifting system is obtained by using variational theory and partial integration method. The specific formula is as follows:

[0072]

[0073] Where, ρ is the linear density of the lifting wire rope, EA is the tensile stiffness of the wire rope, m a To improve the quality of the container and its load, m T is the mass of the floating sheave and the piston rod of the hydraulic cylinder, l is the length of the lifting wire rope, c ir To increase the longitudinal damping coefficient of the wire rope, c ic To increase the longitudinal damping coefficient at the container, c is is the damping coefficient at the floating sheave, F i (t) is the exciting force applied by the floating sheave to the wire rope, F i (t) is the exciting force applied to the wire rope by the floating sheave.

[0074] S2: Based on the uncertain parameters and the unknown disturbance force, an adaptive robust boundary controller for wire rope tension balance is formed with wire rope tension balance control and lifting container longitudinal vibration suppression as control objectives.

[0075] Specifically, a tension sensor is installed at the connection between the two steel wire ropes and the lifting container to obtain the tension H1 and tension H2 at the connection; the deviation is calculated based on the tension measurement value, and the specific formula is as follows:

[0076] ω f (t) = H1-H2.

[0077] Furthermore, based on the overall kinetic energy, overall potential energy and tension deviation, an adaptive robust boundary controller is set to construct the Lyapunov function. The specific formula is as follows:

[0078] V(t)=α z V1(t)+β z V2(t)

[0079]

[0080] Among them, v(t) is the lifting speed, α z and β z is the positive definite weight coefficient, α z >0,β z >0, V1(t) is the rate of increase of total kinetic energy and total potential energy, and V2(t) is the rate of increase of tension deviation.

[0081] Furthermore, the damping coefficient of the lifting container, the change of the load mass and the difference in the wire rope density are defined as the uncertain parameters of the double-rope winding lifting system θ = [c 1c c 2c m a ρ] Τ , the estimated vector is And make bounded estimates of the unknown disturbance forces.

[0082] It should be noted that the unknown interference force d i (t) is unknown and bounded, that is, |d i (t)|≤D i , D i >0, i=1,2. Rewrite the boundary state equation, the specific formula is as follows:

[0083]

[0084] Specifically, according to the estimation errors of uncertain parameters and unknown disturbance forces, the Lyapunov function is redefined and the control law and adaptive law are designed.

[0085] It should be noted that the specific formula for redefining the Lyapunov function is as follows:

[0086]

[0087] Among them, Λ=diag{λ1λ2λ3λ4} is the positive parameter matrix, λ i (i=1,2,3,4)>0 is adaptive gain.

[0088] Furthermore, based on the control law and the adaptive law, the Lyapunov stability theory is used to make the container vibration displacement and the wire rope tension difference converge to zero, thereby achieving wire rope tension balance control and lifting container longitudinal vibration suppression.

[0089] Furthermore, the specific formulas of the control law and the adaptive law are as follows:

[0090]

[0091] Among them, F1 is the control law of overall kinetic energy and overall potential energy, and F2 is the control law of tension deviation. is the adaptive law of total kinetic energy and total potential energy, is the adaptive law of the ith wire rope with tension deviation, ui'(x,t) is the longitudinal vibration displacement of the ith wire rope at spatial position x and time t after coordinated control, d i (t) is the unknown disturbance force, is the interference upper bound D i The estimated value of k l1 , kr1 , k l2 , k r2 , k l3 and k r3 is the control parameter, N1 and N2 are the dynamic characteristics of the double-rope winding lifting system, and the specific formula is as follows:

[0092]

[0093] S3: Apply the adaptive robust controller to the double-rope winding lifting system and implement a control strategy to keep the wire rope tension balanced and effectively suppress the longitudinal vibration of the lifting container.

[0094] Furthermore, this embodiment also provides a computer device, which is suitable for the case of a double-rope winding lifting system wire rope tension balance coordination control method, including a memory and a processor; the memory is used to store computer executable instructions, and the processor is used to execute computer executable instructions to implement the double-rope winding lifting system wire rope tension balance coordination control method proposed in the above embodiment.

[0095] The computer device may be a terminal, and the computer device includes a processor, a memory, a communication interface, a display screen and an input device connected via a system bus. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The communication interface of the computer device is used to communicate with an external terminal in a wired or wireless manner, and the wireless manner can be achieved through WIFI, an operator network, NFC (near field communication) or other technologies. The display screen of the computer device may be a liquid crystal display screen or an electronic ink display screen, and the input device of the computer device may be a touch layer covering the display screen, or a key, trackball or touchpad provided on the housing of the computer device, or an external keyboard, touchpad or mouse, etc.

[0096] This embodiment also provides a storage medium on which a computer program is stored, and when the program is executed by a processor, the following steps are implemented: according to the coupled vibration between the wire rope and the lifting container, a dynamic model of a double-rope winding lifting system is established, wherein the double-rope winding lifting system includes uncertain parameters and unknown interference forces; based on the uncertain parameters and the unknown interference forces, an adaptive robust boundary controller for wire rope tension balance is formed with wire rope tension balance control and lifting container longitudinal vibration suppression as control targets; the adaptive robust controller is applied to the double-rope winding lifting system, and a control strategy is implemented to keep the wire rope tension balanced and effectively suppress the longitudinal vibration of the lifting container. .

[0097] In summary, the present invention effectively solves the problems of unbalanced wire rope tension and vibration in the traditional lifting system by constructing a multi-coordinate system dynamic model and an adaptive robust boundary controller; introduces a fixed coordinate system and a following coordinate system, comprehensively considers the system's kinetic energy, potential energy and damping characteristics, and combines real-time monitoring with a tension sensor to achieve accurate compensation for the system's uncertain parameters and unknown interference forces; the control law and adaptive law designed through the Lyapunov stability theory can not only make the wire rope tension dynamically balanced, but also effectively suppress the longitudinal vibration of the lifting container, significantly improve the stability, accuracy and reliability of the double-rope lifting system, and provide a new theoretical method and technical path for the intelligent control of complex engineering systems.

[0098] Example 2

[0099] Reference Figure 3 to Figure 12 , which is the second embodiment of the present invention, and provides a method for balancing and coordinating the tension of wire ropes in a double-rope winding lifting system. In order to verify the beneficial effects of the present invention, scientific demonstration is carried out through economic benefit calculation and simulation experiments.

[0100] Specifically, the control strategy designed in the present invention is verified by building a double-rope winding lifting system test bench. In order to simulate the situation of unbalanced wire rope tension, the lifting heights of the two winches are set to be different, and the lifting reference curve is as follows: Figure 3 shown.

[0101] Furthermore, the tension feedback signals of the two steel ropes, such as Figure 4 As shown in the figure, as the lifting height continues to increase, the difference in the elongation of the two steel wire ropes gradually increases. Due to the constraint of the rigid tank channel on the lifting container, the container cannot deflect in the horizontal direction. Therefore, the bearing capacity of the two steel wire ropes gradually differs. After the lifting reaches the highest point and stabilizes, the tension difference between the two steel wire ropes is 400N. Subsequently, the traditional PID controller is used to balance the tension difference of the steel wire ropes. The tension feedback curves of the two steel wire ropes are shown in the figure below. Figure 5 As shown in the figure, at the beginning of the lifting, the difference in the tension of the two wire ropes is not obvious because the lifting height of the two wire ropes is small. As the lifting height increases, although the PID controller has a certain inhibitory effect on the tension difference, due to the increase in system interference in the middle of the lifting, the PID controller cannot completely adjust the tension difference between the two wire ropes, and some jitter will occur. However, when it is lifted to the highest point, through the force control of the floating sheave, under the action of the PID controller, the tension of the wire ropes tends to be equal.

[0102] Furthermore, the adaptive robust boundary controller proposed in this paper is used to adjust the balance of wire rope tension difference in the lifting system. The wire rope tension feedback curve is as follows: Figure 6As shown in the figure, although the acceleration changes greatly during the start and stop phase of the lifting, causing the wire rope to produce a large tension oscillation, the tension of the two wire ropes can maintain good consistency during the entire lifting process. The tension of the two wire ropes under the three working conditions is subtracted, and the results are as follows: Figure 7 As shown in the figure, compared with the lifting system without control and PID control, the tension difference of the wire rope is well suppressed by the adaptive robust boundary controller, and the peak value of the tension difference is reduced from 1450N without control and 750N under PID control to 500N. At the same time, the tension oscillation amplitude is also reduced from 1300N without control and 900N under PID control to 650N.

[0103] Specifically, to further illustrate the effect of this method on the vibration suppression of the wire rope and the lifting container, as shown in FIG. Figure 8 , Fig. 9 and Fig.10 As shown, the vibration acceleration curves of the two steel wire ropes at the container end under different control methods are given respectively. It can be seen from the figure that in the absence of control, the container always maintains a large vibration acceleration, and a vibration peak will appear at the moment of acceleration change, and the maximum vibration acceleration reaches 15m / s2. After adopting the PID controller, although the vibration of the container is suppressed, the suppression effect on the vibration amplitude is relatively limited, and the maximum vibration acceleration reaches 11m / s2. Finally, the adaptive robust boundary controller designed by the present invention is adopted to suppress the vibration of the lifting container well, but because the system is mostly a rigid structure, there are also some signal extremes in the feedback vibration acceleration. The maximum vibration acceleration is 6m / s2.

[0104] Furthermore, the vibration acceleration signal under each working condition is integrated twice to obtain the corresponding container vibration displacement curve, such as Fig.11 and Fig.12 As shown. Although the PID controller has a certain suppressing effect on the vibration of the lifting container compared to the uncontrolled case, due to poor stability, jitter occurs during the descent process, causing large fluctuations in the vibration displacement of the container. After adopting the controller proposed in the present invention, the vibration displacement of the container is also well suppressed. The peak value of the vibration displacement is reduced from 2.3×10-3m to 0.8×10-3m.

[0105] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A method for balancing and coordinating the tension of steel wire ropes in a double-rope winding lifting system, characterized in that: include, According to the coupled vibration between the wire rope and the lifting container, a dynamic model of a double-rope winding lifting system is established, wherein the double-rope winding lifting system includes uncertain parameters and unknown interference forces; Based on the uncertain parameters and the unknown disturbance force, an adaptive robust boundary controller for wire rope tension balance is formed with wire rope tension balance control and lifting container longitudinal vibration suppression as control targets; The adaptive robust controller is applied to the double-rope winding lifting system, and a control strategy is implemented to balance the tension of the wire rope and effectively suppress the longitudinal vibration of the lifting container.

2. The method for balancing and coordinating the tension of the steel wire ropes in a double-rope winding lifting system according to claim 1, characterized in that: The method for constructing the kinetic model is: The system motion is described by setting a fixed coordinate system and a follower coordinate system, wherein the fixed coordinate system represents the macroscopic lifting motion of the system, and the follower coordinate system represents the vibration motion of each component of the system; Defining parameters of the system motion, wherein the parameters include total lifting height L, lifting speed v, lifting acceleration a and lifting wire rope length l; According to the parameters, the vibration characteristics are analyzed, and the longitudinal vibration displacement u(x, t) of the particle at the spatial position x of the vertical lifting wire rope is recorded at time t, and the dynamic tension F of this particle is calculated. d (x, t) is expressed as the sum of the quasi-static tension T(x, t) and the elastic force EAε(x, t), and the specific formula is as follows: F d (x,t)=T(x,t)+EAε(x,t) Among them, EA is the tensile stiffness of the wire rope, ε is the positive strain, and it represents the partial derivative of the longitudinal vibration displacement u(x, t) with respect to the spatial position x.

3. The method for balancing and coordinating the tension of the steel wire ropes in a double-rope winding lifting system according to claim 2, characterized in that: Also includes, According to the dynamic tension F d (x, t), taking into account the kinetic energy, elastic potential energy and gravitational potential energy of the two steel cables, the kinetic energy and gravitational potential energy of the two floating sheaves, and the kinetic energy and elastic potential energy of the lifting container; At the same time, the energy consumption items are analyzed by considering the damping force of the two steel cables, the damping of the lifting container, the damping of the floating sheave, and the virtual work done by the exciting force exerted by the floating sheave; Based on Hamilton's principle, a dynamic model is constructed through various kinetic energy, elastic potential energy and virtual work; Based on the dynamic model described in the dynamic model, the overall dynamic model of the double-rope winding lifting system is obtained by using variational theory and partial integration method.

4. The method for balancing and coordinating the tension of the steel wire ropes in a double-rope winding lifting system according to claim 3, characterized in that: The dynamic model includes overall kinetic energy, overall potential energy and virtual work; the specific formula of the overall dynamic model is as follows: Where, ρ is the linear density of the lifting wire rope, EA is the tensile stiffness of the wire rope, m a To improve the quality of the container and its load, m T is the mass of the floating sheave and the piston rod of the hydraulic cylinder, l is the length of the lifting wire rope, c ir To increase the longitudinal damping coefficient of the wire rope, c ic To improve the longitudinal damping coefficient at the container, c is is the damping coefficient at the floating sheave, F i (t) is the exciting force applied by the floating sheave to the wire rope, F i (t) is the exciting force applied to the wire rope by the floating sheave.

5. The method for balancing and coordinating the tension of the steel wire ropes in a double-rope winding lifting system according to claim 4, characterized in that: The specific formula of the overall kinetic energy is as follows: Among them, E k is the total kinetic energy, l(t) is the length of the lifting wire rope, v(t) is the lifting speed, x is the spatial position of the lifting wire rope, t is the time, u i (x, t) is the longitudinal vibration displacement of the ith wire rope at spatial position x and time t; The specific formula of the overall potential energy is as follows: Among them, E p is the total potential energy, T i (x, t) is the lateral vibration displacement of the ith wire rope at spatial position x and time t; The specific formula of the virtual work is as follows: Among them, δW is virtual work, c ir To increase the longitudinal damping coefficient of the wire rope, c ic To improve the longitudinal damping coefficient at the container, c is is the damping coefficient at the floating sheave, F i (t) is the exciting force applied to the wire rope by the floating sheave.

6. The method for balancing and coordinating the tension of the steel wire ropes in a double-rope winding lifting system according to claim 5, characterized in that: Based on the uncertain parameters and the unknown disturbance force, an adaptive robust boundary controller for wire rope tension balance is formed with wire rope tension balance control and lifting container longitudinal vibration suppression as control targets, including: Install a tension sensor at the connection between the two steel wire ropes and the lifting container to obtain the tension H1 and tension H2 at the connection; The deviation is calculated based on the tension measurement value, and the specific formula is as follows: oh f (t)=H1-H2; Based on the overall kinetic energy, the overall potential energy and the tension deviation, an adaptive robust boundary controller is set to construct a Lyapunov function. The specific formula is as follows: V(t)=α z V1(t)+β z V2(t) Among them, v(t) is the lifting speed, α z and β z is the positive definite weight coefficient, V1(t) is the rate of increase of the overall kinetic energy and overall potential energy, and V2(t) is the rate of increase of the tension deviation.

7. The method for balancing and coordinating the tension of the steel wire ropes in a double-rope winding lifting system according to claim 6, characterized in that: Also includes: The damping coefficient of the lifting container, the change of the load mass and the difference in the wire rope density are defined as the uncertain parameters of the double-rope winding lifting system θ = [c 1c c 2c m a ρ] Τ , the estimated vector is and provide bounded estimates of unknown disturbance forces; Redefine the Lyapunov function according to the estimation error of the uncertain parameter and the unknown disturbance force, and design the control law and the adaptive law; Based on the control law and the adaptive law, the container vibration displacement and the wire rope tension difference are converged to zero through the Lyapunov stability theory, thereby achieving wire rope tension balance control and lifting container longitudinal vibration suppression.

8. The method for balancing and coordinating the tension of the steel wire ropes in a double-rope winding lifting system according to claim 7, characterized in that: The specific formulas of the control law and the adaptive law are as follows: Among them, F1 is the control law of overall kinetic energy and overall potential energy, and F2 is the control law of tension deviation. is the adaptive law of total kinetic energy and total potential energy, is the i-th wire rope adaptive law of tension deviation, u' i (x, t) is the longitudinal vibration displacement of the ith wire rope at the spatial position x and time t after coordinated control, d i (t) is the unknown disturbance force, N1 and N2 are the dynamic characteristics of the double-rope winding lifting system, is the interference upper bound D i The estimated value of k l1 , k r1 , k l2 , k r2 , k l3 and k r3 is the control parameter.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method for coordinated control of wire rope tension balance of a double-rope winding lifting system according to any one of claims 1 to 8 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method for coordinated control of wire rope tension balance of a double-rope winding lifting system according to any one of claims 1 to 8 are implemented.

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