Submarine cable tension automatic control system and method based on dance wheel displacement

Abstract

The invention relates to the technical field of submarine cable laying, and particularly discloses a submarine cable tension automatic control system based on dance wheel displacement, which comprises a submarine cable tray, a dance wheel and a PLC automatic controller, a submarine cable is placed in the submarine cable tray, the bottom of the submarine cable tray is provided with a tray driving motor, the dance wheel is arranged on the outer side of the submarine cable tray, and the PLC automatic controller is connected with the submarine cable tray. The lifting supporting piece is installed on the base and arranged in the traction direction of the submarine cable, the dance wheel is installed on the lifting supporting piece, a displacement sensor is arranged on the dance wheel, the submarine cable penetrates through the lower end of the dance wheel, and the tray driving motor and the displacement sensor are electrically connected with the PLC automatic controller. According to the invention, the PLC automatic controller estimates the tension of the submarine cable according to the electric signal sent by the displacement sensor, and controls the tension of the submarine cable by adjusting the rotating speed of the tray driving motor, thereby improving the stability and reliability of the submarine cable laying process, realizing more accurate tension control, reducing the operation difficulty, improving the automation level, and being high in adaptability and high in practicability. The device is suitable for different types of submarine cable laying projects.

Description

Technical Field

[0001] The present invention relates to the technical field of submarine cable laying, and in particular to an automatic submarine cable tension control system and method based on dancing wheel displacement. Background Art

[0002] Submarine cables are cables wrapped in insulating materials and laid on the seabed for telecommunication transmission. Submarine cables are divided into submarine communication cables and submarine power cables. There are some problems and limitations in the existing tension control technology for laying submarine cables, which affect the efficiency and safety of laying submarine cables.

[0003] Some major problems encountered in the prior art are: Accuracy issues: Existing technologies are often limited in terms of the accuracy of tension control. This is because traditional control systems may not be able to accurately monitor and respond to changes in cable tension in real time, especially in complex and volatile marine environments. Response speed: The dynamic changes during the laying of submarine cables require a fast-response control system to adjust the tension. The existing system does not respond quickly enough and cannot adjust the tension immediately to adapt to sudden changes in the marine environment. System complexity and operational difficulty: Traditional tension control systems are often complex in structure and require highly skilled operators to operate and maintain, which not only increases operating costs but also increases the risk of operating errors; Equipment durability and reliability: The marine environment is harsh, and equipment durability and reliability are core requirements. Existing tension control equipment may not be able to withstand long-term marine environmental erosion, resulting in high equipment failure rate and increased maintenance costs; Adaptability: During the laying of submarine cables, the system needs to have good adaptability to different types of seabed terrain and ocean conditions. Existing technologies are often inefficient in automatically adjusting control parameters to adapt to different working conditions. Safety issues: In emergency situations, such as cable breakage or mechanical failure, the existing tension control system may not be able to take timely and effective measures, increasing safety risks; Data integration and analysis capabilities: Existing systems may lack effective data recording and analysis capabilities, which limits the ability to learn from historical operating data and optimize control strategies; Cost-effectiveness: High-performance tension control systems tend to be costly, which limits their application to small or budget-constrained projects; Therefore, it is necessary to propose an improvement to overcome the defects of the prior art. Summary of the invention

[0004] The purpose of the present invention is to solve the problems in the prior art and to provide a submarine cable tension automatic control system and method based on dancing wheel displacement, so as to solve the problems of accuracy, response speed and reliability during submarine cable laying, while reducing the complexity and operation difficulty of the system and improving the system's adaptability and safety.

[0005] The technical solution of the present invention is: The invention discloses an automatic control system for submarine cable tension based on the displacement of a dancing wheel, comprising a submarine cable tray, a dancing wheel and a PLC automatic controller, wherein the submarine cable is placed in the submarine cable tray, a tray driving motor is provided at the bottom of the submarine cable tray, the dancing wheel is provided at the outside of the submarine cable tray and in the traction direction of the submarine cable, the dancing wheel is installed on a lifting support, a displacement sensor is provided on the dancing wheel, the submarine cable passes through the lower end of the dancing wheel, and the tray driving motor and the displacement sensor are electrically connected to the PLC automatic controller.

[0006] Through the above technical solution, during the laying of the submarine cable, the submarine cable tension drives the dancing wheel to move up and down, and the displacement sensor is used to monitor the displacement data of the dancing wheel and transmit the displacement data to the PLC automatic controller. The PLC automatic controller receives and processes the displacement data of the dancing wheel, and then outputs a signal to the tray drive motor. By changing the rotation speed of the tray drive motor, the defense line speed of the submarine cable tray is changed, thereby realizing the control of the submarine cable tension.

[0007] As a preferred technical solution, the lifting support member includes a fixed rod, a connecting rod is hinged on the fixed rod, the dancing wheel is rotatably mounted on the connecting rod, a limit block is provided on the fixed rod at the lower end of the connecting rod, and an angle is formed between the connecting rod and the fixed rod.

[0008] Among them, the angle between the connecting rod and the fixed rod is less than 90°. During the transmission of the submarine cable, the dancing wheel is affected by the tension of the submarine cable, and the dancing wheel rotates along the hinge axis of the connecting rod and the fixed rod, thereby realizing the up and down movement of the dancing wheel and monitoring the up and down fluctuation displacement of the submarine cable during transmission.

[0009] As a preferred technical solution, it also includes a traction device, which is arranged in the traction direction of the submarine cable, and is provided with a traction motor, a traction wheel and a traction belt. Traction wheels are provided on the left and right sides of the traction device, the traction motor is connected to one of the traction wheels, and the traction belt is installed on the two traction wheels. The traction device is provided with two sets of upper and lower traction belts arranged vertically, and a channel for the submarine cable to pass through is provided between the two sets of traction belts.

[0010] Among them, the traction motor is electrically connected to the PLC automatic controller, the submarine cable passes through the submarine cable channel between the two traction belts, and the PLC automatic controller controls the traction motor to drive the traction belt to rotate, thereby realizing the traction and transportation of the submarine cable.

[0011] As a preferred technical solution, a fixed seat is fixed on the traction device, a cylinder is provided on the fixed seat, a lifting seat is provided on the piston rod of the cylinder, a roller is provided on the lifting seat, and rollers are provided on the inner sides of the traction sides of the two traction belts, and the rollers rotate along the traction direction of the traction device.

[0012] Among them, the cylinder is electrically connected to the PLC automatic controller, and the cylinder drives the lifting seat to move up and down, thereby controlling the distance between the two traction belts. It is used to adjust the traction force of the submarine cable, improves the traction efficiency of the submarine cable, and is suitable for traction operations of submarine cables of different specifications.

[0013] As a preferred technical solution, it also includes a take-up arm, which is installed above the submarine cable tray. The take-up arm is provided with a guide trolley, a guide motor and a transmission chain. The guide motor drives the transmission chain to rotate. The guide trolley is provided with a transmission gear, and the transmission chain is meshed with the transmission gear; the guide trolley is provided with a running wheel, the take-up arm is provided with a guide slideway, and the running wheel is arranged in the guide slideway; the guide trolley is provided with a guide pulley.

[0014] Among them, the guide motor is electrically connected to the PLC automatic controller, and the guide motor drives the guide trolley to move along the take-up arm, which is used for guiding during submarine cable laying, thereby improving the accuracy and efficiency of submarine cable laying.

[0015] As a preferred technical solution, the PLC automatic controller is provided with a touch screen for parameter adjustment and data monitoring, thereby improving the convenience of submarine cable tension control.

[0016] A method for automatically controlling a submarine cable tension system based on dancer wheel displacement, comprising: Step 1: Initialize the PLC automatic controller and set the target tension value of the submarine cable; Step 2: Collect the displacement data of the dance displacement sensor in real time and transmit the data to the PLC automatic controller; Step 3: The PLC automatic control system estimates the current tension based on the displacement data; Step 4: The PLC automatic control system calculates the tension error, which is the difference between the target tension value and the estimated tension value; Step 5: Use PID algorithm to calculate the speed adjustment of the tray drive motor; Step 6: Adjust the speed of the tray drive motor; Step 7: Repeat steps 2 to 6.

[0017] As a preferred technical solution, the PID algorithm calculation steps in step 5 are: (1) PID controller design: give the target value, current deviation, previous deviation, integral value, proportional coefficient, integral coefficient, differential coefficient, output value and feedforward value respectively; The structure PID contains all the parameters and state variables required for PID control, and adds a feedforward_val for feedforward control; this design makes the algorithm more modular and flexible.

[0018] (2): PID parameter initialization; initialization feedforward value; In the PID_param_init function, all parameters of the PID controller are initialized, including the feedforward value; initializing the parameters before the PID controller is used ensures that the PID controller is in a known and stable state.

[0019] (3): Position PID algorithm implementation; Calculate the error between the tension target value and the actual value; Integral term; PID algorithm implementation; Error propagation; Returns the current actual value; In the PosionPID_realize function, the PID algorithm combines proportional, integral and differential control, and adds feedforward control to the control output; on the basis of PID control, the system response is further optimized.

[0020] (4): Signal filtering; Simple moving average filtering; Update filter buffer; Calculate the filtered average value; The filter uses a moving average method to effectively reduce the impact of noise and smooth signal changes; by maintaining the most recent value in a fixed-size buffer, this filtering method can better cope with high-frequency noise in the system.

[0021] (5): Controller main loop; specific implementation of the main control loop.

[0022] This function is part of the main control loop and is usually called in the PLC's timer interrupt service routine; this loop needs to implement real-time calls to the control algorithm, including acquiring sensor data, updating controller status, and applying control outputs.

[0023] Compared with the prior art, the present invention has the following beneficial effects: The submarine cable tension automatic control system and method based on the displacement of a dancing wheel of the present invention comprises a submarine cable tray, a tray driving motor, a dancing wheel and a PLC automatic controller, a displacement sensor is arranged on the dancing wheel, the dancing wheel moves up and down as the submarine cable tension changes, the displacement sensor converts the displacement signal into an electrical signal, the PLC automatic controller estimates the submarine cable tension by the electrical signal emitted by the displacement sensor, and controls the submarine cable tension by adjusting the rotation speed of the tray driving motor, thereby improving the stability and reliability of the submarine cable laying process, realizing more accurate tension control, reducing the difficulty of operation, improving the automation level, having strong adaptability, and being suitable for different types of submarine cable laying projects. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a structural schematic diagram of the automatic control system of submarine cable tension based on dancing wheel displacement of the present invention; Figure 2 It is a schematic diagram of the internal structure of the tractor of the present invention; Figure 3 It is a schematic diagram of the mechanism of the dancing wheel of the present invention; Figure 4 It is a structural schematic diagram of the take-up arm of the present invention; Figure 5 For the present invention Figure 4 An enlarged schematic diagram of part I; Figure 6 Schematic diagram of the automatic control process of the invention.

[0025] In the figure: 1. Cable tray; 2. Support frame; 3. Cable; 4. Tractor; 5. Guide wheel; 6. Dance wheel; 7. Tray drive motor; 8. Take-up arm; 41. Lifting seat; 42. Cylinder; 43. Fixed seat; 44. Roller; 45. Traction motor; 46. Traction wheel; 47. Traction belt; 61. displacement sensor; 62. connecting rod; 63. limit stopper; 64. fixing rod; 81. Guide slide; 82. Conveyor chain; 83. Guide motor; 84. Guide trolley; 85. Guide pulley; 86. Travel wheel; 87. Transmission gear. DETAILED DESCRIPTION

[0026] In order to make the technical means, technical features, invention objectives and technical effects achieved by the present invention easy to understand, the present invention is further explained below with reference to specific illustrations.

[0027] Embodiment 1: like Figure 1 The figure is a schematic diagram of the structure of the automatic control system of submarine cable tension based on dancing wheel displacement of the present invention.

[0028] The submarine cable tension automatic control system based on the displacement of the dancing wheel of this embodiment comprises a submarine cable tray 1, a tractor 4, a dancing wheel 6 and a PLC automatic controller. A base is provided at the bottom of the submarine cable tray 1, and the submarine cable tray 1 is rotatably mounted on the base. A tray driving motor 7 is fixed on the base, and the tray driving motor 7 drives the submarine cable tray 1 to rotate. A support frame 2 is fixed at the center of the base, and the support frame 2 is clearance-matched with the submarine cable tray 1. The upper end of the support frame 2 is fixedly mounted with a tractor 4 and a guide wheel 5. The guide wheels 5 are provided in plurality and are arranged at intervals along the traction direction of the tractor 4. The dancing wheel 6 is fixed on the traction equipment platform, and the dancing wheel 6 is installed on the traction side of the submarine cable 3. The dancing wheel 6 and the support frame 2 are spaced at a set distance, and the submarine cable 3 passes through the lower end of the dancing wheel 6. A take-up arm 8 is also fixed on the support frame 2, and the take-up arm 8 is arranged above the submarine cable tray 1.

[0029] Among them, the tray drive motor 7, the traction device 4 and the electrical components in the system are all electrically connected to the PLC automatic controller, which is used for the overall adjustment and control of the equipment. The PLC automatic controller is equipped with a touch screen to facilitate parameter adjustment and monitoring, thereby ensuring the accuracy and efficiency of the submarine cable tension control and realizing the automation of the submarine cable tension control.

[0030] like Figure 2 FIG. 2 is a schematic diagram of the internal structure of the tractor of the present invention.

[0031] Traction motors 45 are fixed on both the upper and lower sides of the tractor 4. Four traction wheels 46 are installed in the tractor 4. Two traction wheels 46 form a group, and a total of two groups are vertically installed in the tractor 4. The traction motor 45 on the upper side drives the traction wheel group on the upper side to rotate, and the traction motor 45 on the lower side drives the traction wheel group on the lower side to rotate. Traction belts 47 are installed on the traction wheel groups on the upper and lower sides. Fixed seats 43 are fixed on the tractor 4 on the inner sides of the two traction belts 47. Cylinders 42 are fixed on the fixed seats 43. Lifting seats 41 are fixed on the cylinders 42. Rollers 44 are rotatably installed on the lifting seats 41. The rollers 44 are all arranged on the traction side of the traction belt 47. The rollers 44 rotate back and forth along the traction direction of the tractor 4.

[0032] like Figure 3 FIG. 2 is a schematic diagram of the structure of the dancing wheel 6 of the present invention.

[0033] A fixed rod 64 is fixed below the dancing wheel 6 shown, and a connecting rod 62 is hinged on the fixed rod 64. The dancing wheel 6 is rotatably installed on the connecting rod 62. A displacement sensor 61 is fixed on the dancing wheel 6. A limit stopper 63 is fixed on the fixed rod 64 at the lower end of the connecting rod 62. An angle less than 90° is formed between the connecting rod 62 and the fixed rod 64. The submarine cable 3 passes through the lower end of the dancing wheel 6. As the tension of the submarine cable fluctuates, the submarine cable 3 pushes the dancing wheel 6 to rotate along the hinge axis between the connecting rod 62 and the fixed rod 64. The displacement sensor 61 monitors the up and down movement data of the dancing wheel 6 and converts it into an electrical signal, which is transmitted to the PLC automatic controller.

[0034] like Figure 4 and Figure 5 FIG. 2 is a schematic diagram of the structure of the take-up arm of the present invention.

[0035] The take-up arm 8 shown is equipped with a transmission chain 82, a guide trolley 84 and a guide motor 83. The guide motor 83 drives the transmission chain 82 to rotate. The guide trolley 84 is provided with a running wheel 86. The take-up arm 8 is provided with a guide slideway 81. The running wheel 86 is installed in the guide slideway 81. A transmission gear 87 is rotatably installed on the guide trolley 84, and the transmission gear 87 is meshed with the transmission chain 82. Two sets of guide pulleys 85 are installed on the guide trolley 84. A submarine cable channel is reserved between the two sets of guide pulleys 85. The submarine cable 3 passes through the submarine cable channel. The submarine cable 3 moves by sliding the guide trolley 84 driven by the guide motor 83, thereby improving the efficiency and accuracy of laying the submarine cable 3.

[0036] like Figure 6 Shown is a schematic diagram of the automatic control process of the present invention.

[0037] The method of automatically controlling the tension of a submarine cable based on the displacement of a dancing wheel comprises the following steps: Step 1: Initialize the PLC automatic controller and set the target tension value of the submarine cable; Step 2: Collect the displacement data of the dance displacement sensor in real time and transmit the data to the PLC automatic controller; Step 3: The PLC automatic control system estimates the current tension based on the displacement data; Step 4: The PLC automatic control system calculates the tension error, which is the difference between the target tension value and the estimated tension value; Step 5: Use PID algorithm to calculate the speed adjustment of the tray drive motor; Step 6: Adjust the speed of the tray drive motor; Step 7: Repeat steps 2 to 6.

[0038] The PID algorithm in step 5 is described as follows: (1) PID controller design: typedef struct { float target_val; / / target value float Error; / / Current deviation float LastError; / / last deviation float integral; / / integral value float Kp; / / proportional coefficient float Ki; / / integral coefficient float Kd; / / differential coefficient float output_val; / / output value float feedforward_val; / / feedforward value }PID; The structure PID contains all the parameters and state variables required for PID control, and adds a feedforward_val for feedforward control, which realizes the modularity and flexibility of the algorithm, integrates the controller parameters and states into one module, and simplifies the configuration and management of the controller.

[0039] PID parameter initialization: void PID_param_init(PID *pid) { pid->target_val =3600.0; pid->output_val =0.0; pid->Error= 0.0; pid->LastError = 0.0; pid->integral = 0.0; pid->Kp = 10.0; pid->Ki = 0.5; pid->Kd = 0.8; pid->feedforward_val = 0.0; / / Initialize feedforward value } In the PID_param_init function, all parameters of the PID controller are initialized, including the feedforward value. By initializing the data, the PID controller is in a known and stable state before it is actually used by the PLC controller; Position PID algorithm implementation: float PosionPID_realize(PID *pid, float actual_val, float feedforward_val) { / / Calculate the error between the target value and the actual value pid->Error = pid->target_val - actual_val; / / Integral term pid->integral += pid->Error; / / PID algorithm implementation pid->output_val = pid->Kp * pid->Error + pid->Ki * pid->integral + pid->Kd * (pid->Error - pid->LastError) + feedforward_val; / / Add feedforward control / / Error propagation pid->LastError = pid->Error; / / Return the current actual value return pid->output_val; } In the PosionPID_realize function, the PID algorithm combines proportional, integral and differential control, and adds feedforward control to the control output, adding known information of the system to the control. On the basis of PID control, the system response is further optimized, and the control accuracy and response speed are improved; (2) Signal filtering: Simple moving average filtering: float Signal_Filter(float raw_value) { static float filter_buffer

[10] = {0}; static int filter_index = 0; float filter_sum = 0; / / Update filter buffer filter_buffer[filter_index] = raw_value; filter_index = (filter_index + 1) % 10; / / Calculate the average value after filtering for (int i = 0; i<10; i++) { filter_sum += filter_buffer[i]; } return filter_sum / 10; } This filter uses the moving average method to effectively reduce the impact of noise and smooth signal changes. By maintaining the most recent value in a fixed-size buffer, this filtering method can better cope with high-frequency noise in the system, enhance the system's robustness to noise, and improve control stability. (3) Controller main loop void Control_Loop() { static PID posionPID; static int initialized = 0; / / Specific implementation of the main control loop } This function is part of the main control loop and is usually called in the PLC's timer interrupt service routine. This loop needs to implement real-time calls to the control algorithm, including acquiring sensor data, updating controller status, and applying control outputs.

[0040] The above description is only a preferred embodiment of the present invention and is not intended to limit the scope of implementation of the present invention. That is, all equivalent changes and modifications made according to the content of the patent application scope of the present invention should belong to the technical scope of the present invention.

Claims

1. A submarine cable tension automatic control system based on dancing wheel displacement, characterized in that: The invention comprises a submarine cable tray (1), a dancing wheel (6) and a PLC automatic controller. The submarine cable (3) is placed in the submarine cable tray (1). A tray driving motor (7) is provided at the bottom of the submarine cable tray (4). The dancing wheel (6) is provided on the outside of the submarine cable tray (1) and in the pulling direction of the submarine cable (3). The dancing wheel (6) is installed on a lifting support. A displacement sensor (61) is provided on the dancing wheel (6). The submarine cable (3) passes through the lower end of the dancing wheel (6). The tray driving motor (7) and the displacement sensor (61) are both electrically connected to the PLC automatic controller.

2. The submarine cable tension automatic control system based on dancing wheel displacement according to claim 1 is characterized in that: The lifting support member comprises a fixed rod (64), a connecting rod (62) is hinged on the fixed rod (64), the dancing wheel (6) is rotatably mounted on the connecting rod (62), a limit stopper (63) is provided on the fixed rod (64) at the lower end of the connecting rod (62), and an angle is formed between the connecting rod (62) and the fixed rod (64).

3. The submarine cable tension automatic control system based on dancing wheel displacement according to claim 1 is characterized in that: The invention also comprises a tractor (4), wherein the tractor (4) is arranged in the traction direction of the submarine cable (3), and the tractor (4) is provided with a traction motor (45), a traction wheel (46) and a traction belt (47). The tractor (4) is provided with traction wheels (46) on both left and right sides, the traction motor (45) is connected to one of the traction wheels (46), and the traction belt (47) is installed on the two traction wheels (46). The tractor (4) is provided with two groups of traction belts (47) arranged vertically, one above the other, and a passage through which the submarine cable (3) passes is provided between the two groups of traction belts (47).

4. The submarine cable tension automatic control system based on dancing wheel displacement according to claim 3 is characterized in that: A fixed seat (43) is fixed on the tractor (4), a cylinder (42) is provided on the fixed seat (43), a lifting seat (41) is provided on the piston rod of the cylinder (42), a roller (44) is provided on the lifting seat (41), and rollers (44) are provided on the inner sides of the traction sides of the two traction belts (47), and the rollers (44) rotate along the traction direction of the tractor (4).

5. The submarine cable tension automatic control system based on dancing wheel displacement according to claim 1 is characterized in that: The cable tray (1) further comprises a take-up arm (8), the take-up arm (8) being mounted above the submarine cable tray (1), the take-up arm (8) being provided with a guide trolley (84), a guide motor (83) and a transmission chain (82), the guide motor (83) driving the transmission chain (82) to rotate, the guide trolley (84) being provided with a transmission gear (87), the transmission chain (82) being meshed with the transmission gear (87); the guide trolley (84) being provided with a running wheel (86), the take-up arm (8) being provided with a guide slideway (81), the running wheel (86) being arranged in the guide slideway (81); and the guide trolley (84) being provided with a guide pulley (85).

6. The submarine cable tension automatic control system based on dancing wheel displacement according to claim 1 is characterized in that: The PLC automatic controller is provided with a touch display screen.

7. A method for automatically controlling the tension of a submarine cable based on the displacement of a dancing wheel, characterized in that: include: Step 1: Initialize the PLC automatic controller and set the target tension value of the submarine cable; Step 2: Collect the displacement data of the dance displacement sensor in real time and transmit the data to the PLC automatic controller; Step 3: The PLC automatic control system estimates the current tension based on the displacement data; Step 4: The PLC automatic control system calculates the tension error, which is the difference between the target tension value and the estimated tension value; Step 5: Use PID algorithm to calculate the speed adjustment of the tray drive motor; Step 6: Adjust the speed of the tray drive motor; Step 7: Repeat steps 2 to 6.

8. The method for automatically controlling the tension of a submarine cable based on the displacement of a dancing wheel according to claim 7, characterized in that: The PID algorithm calculation steps in step 5 are: (1) PID controller design: give the target value, current deviation, previous deviation, integral value, proportional coefficient, integral coefficient, differential coefficient, output value and feedforward value respectively; The structure PID contains all the parameters and state variables required for PID control, and adds a feedforward_val for feedforward control; (2) PID parameter initialization: Initialize the feedforward value; In the PID_param_init function, all parameters of the PID controller are initialized, including the feedforward value; (3) Position PID algorithm implementation: Calculate the error between the tension target value and the actual value; Integral term; PID algorithm implementation; Error propagation; Returns the current actual value; In the PosionPID_realize function, the PID algorithm combines proportional, integral, and differential control, and adds feedforward control to the control output; (4) Signal filtering: Simple moving average filtering; Update filter buffer; Calculate the filtered average value; (5) Controller main loop: the specific implementation of the main control loop.

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