Stay cable force monitoring system and monitoring method based on magnetoelastic effect

Abstract

The invention discloses an inhaul cable force monitoring system and method based on the magnetoelastic effect. The inhaul cable force monitoring system and method are used for cable force value characterization of ferromagnetic material steel cables such as steel strands and parallel steel wire cables. The inhaul cable force monitoring system comprises a detachable sensor, an inhaul cable magnetizing device, an electromagnetic signal measuring device and a data acquisition and analysis device, the detachable sensor is installed on an inhaul cable and provided with an exciting coil and a signal acquisition coil, the inhaul cable magnetizing device is connected with the exciting coil, and the electromagnetic signal measuring device is connected with the signal acquisition coil. The stay cable force monitoring method comprises the following steps: firstly, carrying out saturation magnetization on the stay cable through the stay cable magnetization device and then carrying out remagnetization; then, measuring medium-high frequency inductance values and resistance values at the two ends of the signal acquisition coil through the electromagnetic signal measurement device so as to represent the cable force; the method is high in repeatability, the overlap ratio of loading and unloading curves is high, and small-range and large-range cable force fluctuation can be accurately monitored.

Description

Technical Field

[0001] The present invention relates to the technical field of structural safety monitoring, and in particular to a cable force monitoring system and method based on magnetoelastic effect, which are applied to fields such as long-span bridge engineering and large-scale building engineering structures. Background Art

[0002] With rapid economic development, large-scale infrastructure is constantly being supplemented and improved. Cables are widely used due to their high strength, light weight, and stable operation. However, due to the long-term alternation of static and dynamic loads, cables' load-bearing capacity fluctuates. Coupled with human factors such as improper construction and maintenance, as well as environmental factors such as rain and snow, cables inevitably suffer from wear, corrosion, and fatigue. In severe cases, some wires may fail, resulting in not only economic losses but also life-threatening situations. Therefore, timely and effective monitoring of cable tension is crucial. If cables can be adjusted, repaired, or replaced before they fail, it is entirely possible to ensure the continued structural safety of bridges and large-scale construction projects, thereby preventing major accidents.

[0003] In recent years, monitoring methods based on the magnetoelastic effect have become increasingly mature, mainly divided into pulse magnetoelastic method and magnetoelastic inductance method. The pulse magnetoelastic method uses pulse excitation and coil induction to extract various parameters of the induction signal to characterize the cable tension. Due to the influence of residual magnetism, multiple pulse excitations are usually required to stabilize the induction value. The required energy is high and the measurement data needs to be analyzed secondary. Frequent high pulse voltages during long-term monitoring pose safety risks and consume high energy. The magnetoelastic inductance method uses AC excitation to measure the inductance value at both ends of the detection coil to characterize the cable tension. Due to the influence of hysteresis characteristics, the loading and unloading curves have a low degree of overlap, are insensitive to small fluctuations in the cable tension, and the accuracy needs to be improved.

[0004] In summary, although there are many studies on the current cable tension monitoring methods, they still cannot achieve long-term cable tension monitoring well, and the safety and accuracy need to be further improved. Summary of the Invention

[0005] In view of the deficiencies in the prior art, the present invention provides a cable force monitoring system and a monitoring method based on the magnetoelastic effect, so as to achieve long-term monitoring of the cable force.

[0006] The present invention discloses a cable force monitoring system based on magnetoelastic effect, comprising a detachable sensor, a cable magnetization device, an electromagnetic signal measuring device and a data acquisition and analysis device;

[0007] The detachable sensor includes an excitation coil, a signal acquisition coil, and a sensor frame. When the sensor frame is a single sensor inner frame, the signal acquisition coil is wound around the middle of the sensor inner frame, and the excitation coil is wound around the sensor inner frame and located on both sides of the signal acquisition coil. When the sensor frame is a combination of a sensor inner frame and a sensor outer frame, the signal acquisition coil is wound around the sensor inner frame, and the excitation coil is wound around the sensor outer frame.

[0008] The cable magnetization device is connected to both ends of the excitation coil and is used to provide a stable pulse signal to magnetize the cable; the cable magnetization device has a debugging interface for receiving the voltage and current of the signal acquisition coil and is used to detect the pulse value required for the saturation magnetization of the cable;

[0009] The electromagnetic signal measuring device is connected to both ends of the signal acquisition coil, and is used to perform AC excitation through a self-excited AC signal after the cable magnetization device generates a pulse signal to magnetize and demagnetize the cable, and to receive the voltage and current values ​​at both ends of the signal acquisition coil, so as to calculate and display the inductance and resistance values ​​at both ends of the signal acquisition coil in real time;

[0010] The data acquisition and analysis device performs signal communication and data transmission with the cable magnetization device and the electromagnetic signal measuring device, and is used to control the excitation parameters of the cable magnetization device and display the signal values ​​at both ends of the excitation coil, as well as to collect the inductance and resistance values ​​at multiple frequencies and different AC signal amplitudes displayed in real time during the operation of the electromagnetic signal measuring device, and to draw a real-time graph of the changes in inductance and resistance values ​​over time.

[0011] As a further improvement of the present invention, the detachable sensor further includes a heat insulation layer and a shielding cover;

[0012] The heat insulation layer wraps the excitation coil and the signal acquisition coil respectively to reduce the influence of temperature change on the sensor performance; the shielding cover wraps the installed and fixed sensor to avoid interference from external electromagnetic signals.

[0013] As a further improvement of the present invention, the sensor inner frame and the sensor inner frame are high-temperature resistant frames, and the excitation coil and the signal acquisition coil are multi-turn enameled wires, which are convenient for on-site installation and arrangement.

[0014] As a further improvement of the present invention, during the cable tension monitoring process, the purpose of the cable magnetization device generating a pulse signal is to magnetize the cable rather than to cause the signal acquisition coil to generate an induction signal; after the electromagnetic signal measuring device is connected to the signal acquisition coil, it has the function of disconnecting and reconnecting at any time, thereby preventing the cable magnetization device from generating an induced current in the signal acquisition coil when the pulse signal is excited, causing damage to the electromagnetic signal measuring device.

[0015] As a further improvement of the present invention, the cable magnetization device and the electromagnetic signal measuring device both contain a signal generator, a power amplifier, a temperature sensor, a solar voltage-stabilized power supply, an energy storage capacitor, a data feedback module and a wireless communication module; the cable magnetization device should be miniaturized and portable, with safe and stable performance; the data acquisition and analysis device has an Internet data transmission function, and can upload the collected and analyzed data to the cloud for backup.

[0016] As a further improvement of the present invention, the measurement frequency of the electromagnetic signal measuring device is 1kHz-100kHz, the measurement accuracy of inductance and resistance is less than 0.001μH and 0.001μΩ respectively, and the update speed of the monitoring data is adjustable.

[0017] As a further improvement of the present invention, the cable tension monitoring system is used to characterize the cable tension value of ferromagnetic material cables including steel strands and parallel steel wire cables.

[0018] As a further improvement of the present invention, the cable tension monitoring system is based on the magnetoelastic effect and hysteresis characteristics of ferromagnetic materials, and characterizes the cable tension by measuring the medium and high frequency inductance or resistance value of the demagnetized cable after saturation magnetization. Both data can accurately monitor the cable tension, and the two data characterizing the cable tension can be measured simultaneously, thereby enhancing the reliability of the cable tension monitoring. In addition, both methods do not require secondary analysis of the derivative information received by the signal acquisition coil, and the current inductance value or resistance value or the increment of the two can be directly observed to determine the cable tension state.

[0019] The present invention also discloses a cable force monitoring method of the cable force monitoring system, comprising:

[0020] Step 1: Install a detachable sensor on the cable, connect the excitation coil to the cable magnetization device, and connect the signal acquisition coil to the debugging interface of the cable magnetization device;

[0021] Step 2: Start the cable magnetization device, electromagnetic signal measurement device, and data acquisition and analysis device, and debug all equipment to ensure the stability of pulse signals, AC signals, and data communications, as well as the accuracy of real-time data acquisition;

[0022] Step 3: Use the data acquisition and analysis device to issue instructions to make the cable magnetization device generate pulse signals of different amplitudes, and analyze and process the data of the debugging interface to obtain the pulse value required for the cable saturation magnetization;

[0023] Step 4: Repeat step 3 and select a suitable pulse value as the excitation signal;

[0024] Step 5. Set the frequency of the electromagnetic signal measuring device to medium-high frequency, which can be selected from 1kHz-100kHz, and set the measurement parameters of the electromagnetic signal measuring device to inductance and resistance values; disconnect the signal acquisition coil connected to the debugging interface of the cable magnetization device, and connect the signal acquisition coil to the electromagnetic signal measuring device;

[0025] Step 6: Keep the frequency of the electromagnetic signal measuring device unchanged, and use the data acquisition and analysis device to issue a command to the cable magnetization device to generate a pulse signal of the pulse value specified in step 4. After the pulse process is completed, the electromagnetic signal measuring device automatically collects real-time data 3-6 times and takes the average value. After the data collection is completed, the data acquisition and analysis device displays the changes in the current inductance and resistance values ​​in real time;

[0026] Step 7: After waiting for a time t, repeat step 6 to continuously monitor the cable tension. The data acquisition and analysis device plots the change of the inductance and resistance values ​​over time in real time, and displays the current cable tension value in real time according to the calibrated cable tension-electromagnetic signal relationship.

[0027] Step 8: Determine whether the cable force is in a safe and reliable state. If the cable force is safe and reliable, repeat step 7. Otherwise, the monitoring system uploads the information urgently and feeds back the warning information to the staff.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] 1. The monitoring system of the present invention has a reasonable structure, is economical and reliable, and is easy to operate. It is sensitive to changes in the cable force value and can accurately measure the cable force value using a single high-energy pulse signal, and has the ability to monitor the cable force for a long time.

[0030] 2. The monitoring method of the present invention is novel and adopts a dual excitation form. Pulse excitation is responsible for magnetizing the cable, and AC excitation is responsible for measuring electromagnetic parameters. This method has strong repeatability, a high degree of overlap between loading and unloading curves, and can achieve accurate monitoring of cable tension fluctuations in both small and large ranges.

[0031] 3. The present invention can simultaneously obtain two signal values ​​that accurately represent the cable force, thereby enhancing the reliability of cable force monitoring. There is no need to perform secondary analysis on the derivative information received by the signal acquisition coil, and the cable force state of the cable can be determined by directly observing the current inductance value or resistance value or its numerical change. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 This is a module schematic diagram of the cable force monitoring system based on magnetoelastic effect disclosed in the present invention;

[0033] Figure 2 This is a flow chart of the cable force monitoring method based on magnetoelastic effect disclosed in the present invention;

[0034] Figure 3 This is a schematic diagram of the installation of sensors of the cable force monitoring system based on magnetoelastic effect disclosed in the present invention.

[0035] In the picture:

[0036] 1. Cable magnetization device; 2. Magnetization device connecting wire; 3. Cable; 4. Sensor outer frame; 5. Excitation coil; 6. Shielding cover; 7. Sensor inner frame; 8. Signal measurement device connecting wire; 9. Signal acquisition coil; 10. Thermal insulation layer; 11. Data acquisition and analysis device; 12. Electromagnetic signal measurement device. DETAILED DESCRIPTION

[0037] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0038] The present invention provides a cable force monitoring system based on magnetoelastic effect, comprising a detachable sensor, a cable magnetization device, an electromagnetic signal measuring device and a data acquisition and analysis device;

[0039] The detachable sensor includes an excitation coil, a signal acquisition coil, and a sensor frame. When the sensor frame is a single sensor inner frame, the signal acquisition coil is wound around the middle of the sensor inner frame, and the excitation coil is wound around the sensor inner frame and located on both sides of the signal acquisition coil. When the sensor frame is a combination of a sensor inner frame and a sensor outer frame, the signal acquisition coil is wound around the sensor inner frame, and the excitation coil is wound around the sensor outer frame.

[0040] The cable magnetization device is connected to both ends of the excitation coil and is used to provide a stable pulse signal to magnetize the cable. The cable magnetization device has a debugging interface for receiving signals to collect coil voltage and current, and is used to detect the pulse value required for saturation magnetization of the cable.

[0041] The electromagnetic signal measuring device is connected to both ends of the signal acquisition coil, and is used to generate a pulse signal in the cable magnetization device to magnetize and demagnetize the cable, and then perform AC excitation through a self-excited AC signal, and receive the voltage and current values ​​at both ends of the signal acquisition coil, so as to calculate and display the inductance and resistance values ​​at both ends of the signal acquisition coil in real time;

[0042] The data acquisition and analysis device conducts signal communication and data transmission with the cable magnetization device and the electromagnetic signal measuring device, and is used to control the excitation parameters of the cable magnetization device and display the signal values ​​at both ends of the excitation coil, as well as to collect the inductance and resistance values ​​at various frequencies and different AC signal amplitudes displayed in real time during the operation of the electromagnetic signal measuring device, and to draw a real-time graph of the changes in inductance and resistance values ​​over time.

[0043] The present invention provides a cable tension monitoring method based on the magnetoelastic effect, which magnetizes the cable through a pulse signal from a magnetizing device and measures electromagnetic parameters through a self-excited spontaneous AC signal. During cable tension monitoring, the cable magnetizing device is connected to an excitation coil and generates a pulse signal to magnetize and then demagnetize the cable. After the pulse process is completed, the medium and high frequency inductance and resistance values ​​at both ends of the signal acquisition coil are measured and transmitted in real time through a self-excited spontaneous electromagnetic signal measuring device. Since changes in cable tension will cause changes in magnetic permeability, and changes in magnetic permeability will cause changes in the measured inductance and resistance values, changes in actual cable tension can be reflected by inductance and resistance values. This method can simultaneously measure two signal values ​​that accurately characterize cable tension, and the loading and unloading curves have a high degree of overlap, so that both small and large-scale cable tension fluctuations can be accurately monitored. The present invention is based on the magnetoelastic effect and hysteresis characteristics of ferromagnetic materials, and characterizes the cable force by measuring the medium and high frequency inductance or resistance value of the demagnetized cable after saturation magnetization. Both data can accurately monitor the cable force, and the two data characterizing the cable force can be measured simultaneously, which enhances the reliability of cable force monitoring. In addition, both methods do not require secondary analysis of the derivative information received by the signal acquisition coil, and the cable force state of the cable can be determined by directly observing the current inductance value or resistance value or the increment of the two.

[0044] The present invention is described in further detail below with reference to the accompanying drawings:

[0045] like Figure 1 As shown, the present invention provides a cable force monitoring system based on magnetoelastic effect, comprising: a cable magnetization device 1, a magnetization device connecting line 2, a sensor outer frame 4, an excitation coil 5, a shielding cover 6, a sensor inner frame 7, a signal measurement device connecting line 8, a signal acquisition coil 9, a thermal insulation layer 10, a data acquisition and analysis device 11 and an electromagnetic signal measurement device 12; specifically:

[0046] The sensor's inner frame 7 is mounted and fixed to the cable 3, with a signal acquisition coil 9 wrapped around it. A thermal insulation layer 10 surrounds the signal acquisition coil 9. The sensor's outer frame 4 is mounted and fixed to the cable 3, with an excitation coil 5 wrapped around it. A shielding cover 6 surrounds the outer frame 4. The cable magnetization device 1 is connected to the excitation coil 5 via a magnetization device connection cable 2. The electromagnetic signal measurement device 12 is connected to the signal acquisition coil 9 via a signal measurement device connection cable 8. A data acquisition and analysis device 11 connects the cable magnetization device 1 and the electromagnetic signal measurement device 12 for communication and data transmission.

[0047] In the above embodiment, preferably, the sensor outer skeleton 4 is installed and arranged on the outside of the sensor inner skeleton 7, and the center positions of the two are located on the same horizontal line; the thermal insulation layer 10 should reduce or avoid the signal acquisition coil 9 being interfered with by temperature, and the shielding cover 6 should avoid the interference of external electromagnetic signals on the sensor.

[0048] In the above embodiment, preferably, the cable magnetization device 1 has a reserved debugging interface, which can be connected to the signal acquisition coil 9 wound around the inner skeleton 7 of the sensor to facilitate the debugging of the pulse excitation value; the data acquisition and analysis device 11 can perform wireless communication and data transmission with the cable magnetization device 1 and the electromagnetic signal measuring device 12, and the electromagnetic signal measuring device 12 has a reserved card slot that can be installed and fixed together with the cable magnetization device 1.

[0049] like Figure 2 As shown, the present invention provides a cable force monitoring method based on the magnetoelastic effect. The monitoring method is implemented based on the above-mentioned monitoring system. The monitoring method is not only applicable to the characterization of cable force values ​​of steel strand cables and parallel wire cables, but also to the characterization of cable force values ​​of other ferromagnetic material cables. The specific steps of cable force monitoring are as follows:

[0050] S1. Install and fix the detachable sensor inner skeleton 7 along the axial direction of the cable 3, wind enameled wire on the sensor inner skeleton 7, remove the paint from both ends of the enameled wire with a knife, tin the two ends, and wrap them with a heat-insulating layer 10; wherein, the enameled wire wound on the sensor inner skeleton 7 serves as the signal acquisition coil 9. Install and fix the sensor outer skeleton 4 along the axial direction of the cable 3, and similarly wind the enameled wire, remove the paint from both ends of the enameled wire, tin the two ends, and wrap them with a heat-insulating layer; wherein, the enameled wire wound on the sensor outer skeleton 4 serves as the excitation coil 5; connect the excitation coil 5 to the cable magnetization device 1 via the magnetization device connecting line 2, connect the signal acquisition coil 9 to the debugging interface of the cable magnetization device 1 via the connecting line, and the data acquisition and analysis device 11 performs wireless communication and data transmission with the cable magnetization device 1 and the electromagnetic signal measuring device 12;

[0051] S2. Start the cable magnetization device 1, the electromagnetic signal measuring device 12, and the data acquisition and analysis device 11, and debug all the equipment to ensure that the cable magnetization device 1 generates a stable pulse signal, the electromagnetic signal measuring device 12 generates a stable AC signal, the data communication between the data acquisition and analysis device 11 and the cable magnetization device 1 and the electromagnetic signal measuring device 12 is stable, and the real-time data collected by the data acquisition and analysis device 11 is accurate;

[0052] S3. Use the data acquisition and analysis device 11 to issue instructions to the cable magnetization device 1 to generate pulse signals of different amplitudes, and analyze and process the data of the debugging interface to obtain the pulse value required for the saturation magnetization of the cable. Although a pulse value that is too low can reduce energy consumption, it will cause the coincidence of the loading and unloading curves to deteriorate; although a pulse value that is too high can ensure the accuracy of monitoring, it will increase energy consumption. Using the pulse value required for saturation magnetization can reduce the energy consumption of continuous monitoring of the cable force and improve the accuracy of continuous monitoring of the cable force;

[0053] S4, repeat step S3 continuously and select a suitable pulse value as the excitation signal;

[0054] S5. Set the frequency of the electromagnetic signal measuring device 12 to a medium-high frequency, preferably 1kHz-100kHz, and set the measurement parameters of the electromagnetic signal measuring device 12 to inductance and resistance. Disconnect the signal acquisition coil 9 connected to the debugging interface of the cable magnetization device 1, and connect the signal acquisition coil 9 to the electromagnetic signal measuring device 12 via the signal measuring device connection line 8. At this time, the connection between the electromagnetic signal measuring device 12 and the signal acquisition coil 9 should be able to be disconnected and reconnected at any time, and the connection status can be controlled by the data acquisition and analysis device 11.

[0055] S6, maintaining the frequency of the electromagnetic signal measuring device 12 unchanged, using the data acquisition and analysis device 11 to issue a command to the cable magnetization device 1 to generate a specified pulse signal. After the pulse magnetization process is completed, the electromagnetic signal measuring device 12 automatically collects real-time data 3-6 times and takes the average value. The interval between two real-time data collections should be greater than the update speed of the electromagnetic signal measuring device 12. After the data collection is completed, the data acquisition and analysis device 11 displays the current inductance value, resistance value and their value changes in real time.

[0056] S7, after waiting for time t, repeat step 6 to continuously monitor the cable tension. The data acquisition and analysis device 11 plots the change of the inductance and resistance values ​​over time in real time, and displays the current cable tension value in real time according to the calibrated cable tension-electromagnetic signal relationship. The data acquisition and analysis device 11 records and stores the cable tension data.

[0057] S8. Determine whether the cable force is in a safe and reliable state. If the cable force is safe and reliable, repeat step 7. Otherwise, the monitoring system urgently uploads and feeds back warning information to the staff.

[0058] Since the main function of the magnetizing device of the present invention is to magnetize the cable, the sensor can be installed in a variety of ways. The specific installation diagram is as follows: Figure 3 Methods 1 and 3 both involve wrapping the excitation coil around the sensor's outer frame and the signal acquisition coil around the sensor's inner frame. Method 2 involves wrapping the excitation coil around the upper and lower sides of the inner frame and the signal acquisition coil around the center. The appropriate installation method can be selected based on the actual cable layout.

[0059] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A cable force monitoring system based on magnetoelastic effect, characterized in that: It includes a detachable sensor, a cable magnetization device, an electromagnetic signal measuring device and a data acquisition and analysis device; The detachable sensor includes an excitation coil, a signal acquisition coil, and a sensor frame. When the sensor frame is a single sensor inner frame, the signal acquisition coil is wound around the middle of the sensor inner frame, and the excitation coil is wound around the sensor inner frame and located on both sides of the signal acquisition coil. When the sensor frame is a combination of a sensor inner frame and a sensor outer frame, the signal acquisition coil is wound around the sensor inner frame, and the excitation coil is wound around the sensor outer frame. The cable magnetization device is connected to both ends of the excitation coil and is used to provide a stable pulse signal to magnetize the cable; the cable magnetization device has a debugging interface for receiving the voltage and current of the signal acquisition coil and is used to detect the pulse value required for the saturation magnetization of the cable; The electromagnetic signal measuring device is connected to both ends of the signal acquisition coil, and is used to generate an AC excitation magnetic field and measure the voltage and current values ​​at both ends of the signal acquisition coil after the cable magnetization process is completed, so as to calculate and display the inductance and resistance values ​​at both ends of the signal acquisition coil in real time; The data acquisition and analysis device performs signal communication and data transmission with the cable magnetization device and the electromagnetic signal measuring device, and is used to control the excitation parameters of the cable magnetization device and display the signal values ​​at both ends of the excitation coil, as well as to collect the inductance and resistance values ​​at multiple frequencies and different AC signal amplitudes displayed in real time during the operation of the electromagnetic signal measuring device, and to draw a real-time graph of the changes in inductance and resistance values ​​over time.

2. The cable force monitoring system based on magnetoelastic effect according to claim 1, characterized in that: The detachable sensor further includes a heat insulation layer and a shielding cover; The heat insulation layer wraps the excitation coil and the signal acquisition coil respectively, and the shielding cover wraps the installed and fixed sensor to prevent interference from external signals.

3. The cable force monitoring system based on magnetoelastic effect according to claim 1, characterized in that: After being connected to the signal acquisition coil, the electromagnetic signal measuring device has the function of being disconnected and reconnected at any time.

4. The cable force monitoring system based on magnetoelastic effect according to claim 1, characterized in that: The measurement frequency of the electromagnetic signal measuring device is 1kHz-100kHz, and the measurement accuracy of inductance and resistance is less than 0.001μH and 0.001μΩ respectively.

5. The cable force monitoring system based on magnetoelastic effect according to claim 1, characterized in that: The cable force monitoring system is used for characterizing the cable force value of a ferromagnetic material steel cable including a steel strand and parallel steel wire cables.

6. A cable force monitoring method based on the cable force monitoring system based on magnetoelastic effect according to any one of claims 1 to 5, characterized in that: include: Step 1: Install a detachable sensor on the cable, connect the excitation coil to the cable magnetization device, and connect the signal acquisition coil to the debugging interface of the cable magnetization device; Step 2: Start the cable magnetization device, electromagnetic signal measurement device, and data acquisition and analysis device, set a reasonable cable force update time interval t, and debug all equipment; Step 3: Use the data acquisition and analysis device to issue instructions to make the cable magnetization device generate pulse signals of different amplitudes, and analyze and process the data of the debugging interface to obtain the pulse value required for the cable saturation magnetization; Step 4: Repeat step 3 and select a suitable pulse value as the excitation signal; Step 5: Set the frequency of the electromagnetic signal measuring device to medium-high frequency, and set the measurement parameters of the electromagnetic signal measuring device to inductance and resistance values; disconnect the signal acquisition coil connected to the debugging interface of the cable magnetization device, and connect the signal acquisition coil to the electromagnetic signal measuring device; Step 6: Keep the frequency of the electromagnetic signal measuring device unchanged, and use the data acquisition and analysis device to issue a command to generate a pulse excitation for the cable magnetization device. After the pulse process is completed, the electromagnetic signal measuring device automatically collects real-time inductance and resistance 3-6 times and takes the average value. After the data collection is completed, the data acquisition and analysis device displays and saves the current inductance and resistance values ​​in real time; Step 7: After waiting for a time t, repeat step 6 to continuously monitor the cable tension. The data acquisition and analysis device plots the change of the inductance and resistance values ​​over time in real time, and displays the current cable tension value in real time according to the calibrated cable tension-electromagnetic signal relationship. Step 8: Determine whether the cable force is in a safe and reliable state. If the cable force is safe and reliable, repeat step 7. Otherwise, the monitoring system uploads the information urgently and feeds back the warning information to the staff.

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