High-voltage cable online fault monitoring system and method

Abstract

The invention relates to a high-voltage cable online fault monitoring system and method, and relates to the field of power generation, power transformation and power distribution. In the embodiment, the fault monitoring system comprises a cable, and the cable comprises at least one wire core and shielding layers arranged around the wire cores respectively; one end of the wire core is connected with a power supply, and the other end is connected with a tail-end electric load; one end, close to the power supply, of the shielding layer is grounded; an insulating layer is arranged between the shielding layer and the wire core; the fault monitoring system further comprises an alternating current sensor, a voltage acquisition system, a current acquisition system, a data transmission system and a data analysis terminal. According to the invention, the insulation performance of the high-voltage cable is monitored in real time, the insulation breakdown fault of the high-voltage cable is accurately predicted, the fault point is quickly and accurately positioned, and the fault position is found before the insulation layer of the high-voltage cable is broken down so as to process the fault in time.

Description

Technical Field

[0001] The present invention relates to the fields of power generation, power transformation and power distribution, and in particular to a high-voltage cable online fault monitoring system and method. Background Art

[0002] High voltage cable refers to power cable used to transmit voltage between 1kV and 1000kV, and is mainly used in power transmission and distribution systems.

[0003] When high-voltage cables are in operation, they are affected by environmental corrosion, high-temperature operation or human damage, and the high-voltage cables become aged or damaged, resulting in a decrease in the insulation performance of the high-voltage cables. At this time, the insulator of the high-voltage cable has produced tree-like or water-like discharge patterns. Although the core has not penetrated the insulation layer at this time, if it continues to develop, when the insulation performance of the high-voltage cable drops to the point where the potential difference is sufficient to penetrate the insulator, a penetrating channel is formed between the core and the insulator of the high-voltage cable, and the cable suffers an insulation breakdown failure, leading to a single-phase or multi-phase short circuit accident.

[0004] At present, the existing technology often uses the method of periodic power outages to test the insulation performance of high-voltage cables. During the power outage, the high-voltage cable is subjected to an AC power frequency withstand voltage test or a series resonance withstand voltage test, and the insulation performance of the high-voltage cable is judged to be qualified based on the resistance value of the high-voltage cable or the withstand voltage time. However, this method cannot monitor the insulation performance of the high-voltage cable in real time. During the operation of the high-voltage cable, power outages will still occur. If not discovered in time, it may even develop into a two-phase or three-phase short circuit accident, affecting the operation of other equipment, causing equipment losses and personal injuries. Summary of the invention

[0005] In view of this, the present invention aims to propose a high-voltage cable online fault monitoring system and method to solve the problem in the prior art that the insulation performance of the high-voltage cable cannot be monitored in real time and the cable insulation breakdown fault cannot be predicted.

[0006] To achieve the above object, the technical solution of the present invention is achieved as follows:

[0007] A first aspect of the present invention provides an online fault monitoring system for a high-voltage cable, comprising a cable, wherein the cable comprises at least one core and a shielding layer respectively arranged around each core; one end of the core is connected to a power supply, and the other end is connected to a terminal power load; the shielding layer is grounded at one end close to the power supply; an insulating layer is arranged between the shielding layer and the core, and the fault monitoring system further comprises:

[0008] AC current sensor, voltage acquisition system, current acquisition system, data transmission system and data analysis terminal;

[0009] The AC current sensor is used to monitor the induced current of the shielding layer at the grounding point;

[0010] The voltage acquisition system is used to collect the induced voltage data of the AC current sensor;

[0011] The current acquisition system is used to collect induced current data of the AC current sensor;

[0012] The data transmission system is used to transmit the induced voltage data collected by the voltage collection system and the induced current data collected by the current collection system to the data analysis terminal;

[0013] The data analysis terminal is used to obtain the induced voltage data and the induced current data sent by the data transmission system, calculate the discharge position of the shielding layer according to the induced current data, and then determine the fault position of the cable.

[0014] Furthermore, the AC current sensor is a Rogowski coil.

[0015] Furthermore, the voltage acquisition system includes a resistor, a capacitor, an amplifier and a voltage acquisition unit;

[0016] The first output end of the Rogowski coil is connected to one end of the resistor, and the other end of the resistor is connected to one end of the capacitor and the inverting input end of the amplifier respectively;

[0017] The second output end of the Rogowski coil is connected to the in-phase input end of the amplifier and the second input end of the voltage acquisition unit respectively;

[0018] The output end of the amplifier is connected to the other end of the capacitor and the first input end of the voltage acquisition unit.

[0019] Further, the current collection system includes a current collection unit;

[0020] The first end of the current collection unit is connected to the second output end of the Rogowski coil;

[0021] The second end of the current acquisition unit is connected to the in-phase input end of the amplifier and the second input end of the voltage acquisition unit.

[0022] Further, the data transmission system includes an analog-to-digital conversion module and a communication management machine;

[0023] The output end of the current acquisition unit is connected to the first input end of the analog-to-digital conversion module;

[0024] The output end of the voltage acquisition unit is connected to the second input end of the analog-to-digital conversion module;

[0025] The output end of the analog-to-digital conversion module is connected to the input end of the communication management machine;

[0026] The output end of the communication management machine is connected to the data analysis terminal.

[0027] Furthermore, the data transmission system further comprises a switch;

[0028] The output end of the communication management machine is connected to the first end of the switch; the second end of the switch is connected to the data analysis terminal.

[0029] Furthermore, the shielding layer is a metal shielding layer.

[0030] A second aspect of the present invention provides a method for online fault monitoring of a high-voltage cable, which is applied to a data analysis terminal as described in any one of the first aspects, and the method comprises:

[0031] Acquiring the induced current data sent by the data transmission system;

[0032] Extract the ith abnormal current waveform and the (i+1)th abnormal current waveform having the same current direction as the ith abnormal current waveform from the induced current data, and calculate the time difference Δt between the two abnormal current waveforms i ; Wherein, i is an integer greater than 0;

[0033] According to formula 1

[0034]

[0035] Calculate the mean of the time difference Where n is the time difference Δt between the ith abnormal current waveform and the (i+1)th abnormal current waveform with the same current direction as the ith abnormal current waveform. i Total number of;

[0036] According to formula 2

[0037]

[0038] Calculate the distance L between the discharge position of the shielding layer and the AC current sensor, where V is the propagation speed of the current in the shielding layer;

[0039] The distance L between the discharge position of the shielding layer and the AC current sensor is taken as the distance between the fault position of the cable and the AC current sensor.

[0040] Further, after taking the distance L between the fault position of the cable and the AC current sensor as the distance L, the method further comprises:

[0041] Generates an alarm signal and outputs the distance between the fault location of the cable and the AC current sensor.

[0042] Furthermore, after acquiring the induced current data sent by the data transmission system, the method further includes:

[0043] Acquire induced voltage data sent by a data transmission system;

[0044] Outputs the induced current data and induced voltage data.

[0045] Compared with the prior art, the present invention has the following advantages:

[0046] In the present invention, the induced current of the shielding layer at the grounding point is monitored by an AC current sensor; the induced voltage data of the AC current sensor is collected by a voltage acquisition system; the induced current data of the AC current sensor is collected by a current acquisition system; the induced voltage data collected by the voltage acquisition system and the induced current data collected by the current acquisition system are transmitted to a data analysis terminal by a data transmission system; the induced voltage data and induced current data sent by the data transmission system are obtained by the data analysis terminal, and the discharge position of the shielding layer is calculated according to the induced current data, and then the fault position of the cable is determined. In this way, the insulation performance of the high-voltage cable is monitored in real time, and the insulation breakdown fault of the high-voltage cable is accurately predicted. The fault point can be quickly and accurately located, and the fault position can be found before the insulation layer of the high-voltage cable breaks down. The fault position can be quickly located by fault ranging, and the fault position can be found and handled in time. This is to prevent the insulation breakdown from continuing to develop and forming a ground short circuit fault, affecting the safe operation of the production equipment, and avoiding production losses and personal injuries. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

[0048] Figure 1 It is a structural schematic diagram of a high-voltage cable online fault monitoring system of the present invention;

[0049] Figure 2 A single-core high-voltage cable of the present invention;

[0050] Figure 3 A three-core high-voltage cable of the present invention;

[0051] Figure 4 is a potential difference curve between the fault point and the shielding layer when a fault occurs in the present invention;

[0052] Figure 5 is the current curve of the shielding layer when a fault occurs in the present invention;

[0053] Figure 6 This is the current curve of the shielding layer received by the Rogowski coil when a fault occurs in the present invention.

[0054] Description of reference numerals:

[0055] 1. Wire core; 2. Insulation layer; 3. Shielding layer; 4. Insulation sheath. DETAILED DESCRIPTION

[0056] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0057] In the description of the present invention, it should be noted that the directions or positional relationships indicated by the terms "upper", "lower", "inner", "back", etc. are based on the directions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0058] In addition, in the description of the present invention, unless otherwise clearly defined, the terms "installed", "connected", "connected", and "connector" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood in combination with specific circumstances.

[0059] The following will refer to the attached Figures 1 to 6 The present invention is described in detail with reference to embodiments.

[0060] Overall, if Figure 1 As shown, the first embodiment of the present invention provides a high-voltage cable online fault monitoring system, including a cable, the cable including at least one core 1 and a shielding layer 3 respectively arranged around each core 1; one end of the core 1 is connected to a power source ( Figure 1 The other end is connected to the end power load ( Figure 1 The shielding layer 3 is grounded at one end close to the power supply; an insulating layer 2 is provided between the shielding layer 3 and the core 1, and the online fault monitoring system further includes:

[0061] AC current sensor, voltage acquisition system, current acquisition system, data transmission system and data analysis terminal;

[0062] An AC current sensor for monitoring the induced current of the shielding layer 3 at the grounding point;

[0063] A voltage acquisition system is used to collect the induced voltage data of the AC current sensor;

[0064] A current acquisition system is used to collect induced current data of an AC current sensor;

[0065] A data transmission system, used for transmitting the induced voltage data collected by the voltage collection system and the induced current data collected by the current collection system to the data analysis terminal;

[0066] The data analysis terminal is used to obtain the induced voltage data and induced current data sent by the data transmission system, calculate the discharge position of the shielding layer 3 according to the induced current data, and then determine the fault position of the cable.

[0067] In this embodiment, the cable can be a single-core cable or a three-core cable. When the cable is a single-core cable, Figure 2 , which includes a core 1 and a shielding layer 3 arranged around each core 1; one end of the core 1 is connected to the power supply, and the other end is connected to the terminal power load; the shielding layer 3 is grounded at the end close to the power supply; an insulating layer 2 is arranged between the shielding layer 3 and the core 1; an insulating outer sheath is arranged around the shielding layer 3. The insulation breakdown fault in this embodiment is the process of the core 1 breaking through the insulating layer 2 to form a current loop.

[0068] When the cable has three cores, Figure 3 , which includes a core 1 and a shielding layer 3 respectively arranged around each core 1; one end of the core 1 is connected to the power supply, and the other end is connected to the terminal electrical load; the shielding layer 3 is grounded at the end close to the power supply; an insulating layer 2 is arranged between the shielding layer 3 and the core 1; the cable also includes an insulating outer sheath, and the insulating sheath 4 surrounds the shielding layer 3 of the three cores 1. The insulation breakdown fault in this embodiment is the process in which the core 1 breaks through the insulating layer 2 and forms a current loop with the shielding layer 3.

[0069] Among them, the functions of shielding layer 3 include:

[0070] Limiting the electric field: The shielding layer 3 can strengthen the effect of limiting the electric field in the insulating layer 2, so that the direction of the electric field is consistent with the insulation radius direction (ie radial), so that the electric field terminates on the metal belt, and there is no electric field outside the metal belt.

[0071] Prevent electromagnetic interference: Shielding layer 3 can prevent external electromagnetic interference from entering the cable, and at the same time prevent the signal energy transmitted inside the cable from leaking to the external environment, ensuring that the signal is not affected or less affected by the electromagnetic noise generated by other equipment and the environment during transmission, thereby maintaining the integrity and accuracy of the signal.

[0072] Grounding protection: If the core 1 is damaged, the outflowing current can flow into the grounding grid through the shielding layer 3, which plays a role in safety protection. In addition, the shielding layer 3 can also shield the electromagnetic field to prevent the magnetic field generated by the current from affecting the normal operation of electrical components.

[0073] Homogenizing the electric field: The shielding layer 3 can homogenize the electric field, reducing the risk of local discharge and electrical breakdown of the insulating layer 2 caused by the electric field.

[0074] Protect operators and equipment: When a high-voltage cable breaks down, the high potential quickly and directly enters the ground to prevent electric shock to operators or patients, thus protecting personal safety.

[0075] Improving the insulation performance of the cable: By adding a shielding layer 3 of semi-conductive material on the surface of the conductor, local discharge between the conductor and the insulating layer 2 is avoided, thereby improving the insulation performance of the cable.

[0076] The shielding layer 3 of the high-voltage cable plays an important role in limiting the electric field, preventing electromagnetic interference, grounding protection, and homogenizing the electric field, ensuring the safe and stable operation of the cable. The shielding layer 3 plays a role in safety protection when the current flows into the grounding grid through the shielding layer 3 when grounding. The partial discharge flow path of the present invention is to form a path through the shielding layer 3, measure the size of the leakage current, and judge the strength of the partial discharge.

[0077] More specifically, the AC current sensor is a Rogowski coil.

[0078] More specifically, the voltage acquisition system includes a resistor, a capacitor, an amplifier, and a voltage acquisition unit;

[0079] The first output end of the Rogowski coil is connected to one end of the resistor, and the other end of the resistor is connected to one end of the capacitor and the inverting input end of the amplifier respectively;

[0080] The second output end of the Rogowski coil is connected to the in-phase input end of the amplifier and the second input end of the voltage acquisition unit respectively;

[0081] The output end of the amplifier is connected to the other end of the capacitor and the first input end of the voltage acquisition unit.

[0082] More specifically, the current acquisition system includes a current acquisition unit;

[0083] The first end of the current collection unit is connected to the second output end of the Rogowski coil;

[0084] The second end of the current acquisition unit is connected to the in-phase input end of the amplifier and the second input end of the voltage acquisition unit.

[0085] More specifically, the data transmission system includes an analog-to-digital conversion module and a communication management machine;

[0086] The output end of the current acquisition unit is connected to the first input end of the analog-to-digital conversion module;

[0087] The output end of the voltage acquisition unit is connected to the second input end of the analog-to-digital conversion module;

[0088] The output end of the analog-to-digital conversion module is connected to the input end of the communication management machine;

[0089] The output end of the communication management machine is connected to the data analysis terminal.

[0090] More specifically, the data transmission system further includes a switch;

[0091] The output end of the communication management machine is connected to the first end of the switch; the second end of the switch is connected to the data analysis terminal.

[0092] More specifically, the shielding layer 3 is a metal shielding layer.

[0093] A second embodiment of the present invention provides a method for online fault monitoring of a high-voltage cable, which is applied to a data analysis terminal as in the first embodiment, and the method includes:

[0094] Step S1, acquiring the induced current data sent by the data transmission system;

[0095] Step S2: extract the ith abnormal current waveform and the (i+1)th abnormal current waveform having the same current direction as the ith abnormal current waveform from the induced current data, and calculate the time difference Δt between the two abnormal current waveforms. i ; Wherein, i is an integer greater than 0;

[0096] Step S3: According to formula 1

[0097]

[0098] Calculate the mean of the time difference Where n is the time difference Δt between the ith abnormal current waveform and the (i+1)th abnormal current waveform with the same current direction as the ith abnormal current waveform. i Total number of;

[0099] Step S4: According to formula 2

[0100]

[0101] Calculate the distance L between the discharge position of the shielding layer 3 and the AC current sensor, where V is the propagation speed of the current in the shielding layer 3;

[0102] Step S5: taking the distance L between the discharge position of the shielding layer 3 and the AC current sensor as the distance between the fault position of the cable and the AC current sensor.

[0103] More specifically, after taking L as the distance between the fault position of the cable and the AC current sensor, the method further comprises:

[0104] Generates an alarm signal and outputs the distance between the fault location of the cable and the AC current sensor.

[0105] More specifically, after acquiring the induced current data sent by the data transmission system, the method further includes:

[0106] Acquire induced voltage data sent by a data transmission system;

[0107] Outputs the induced current data and induced voltage data.

[0108] The working principle of the present invention is as follows: Figure 4 As shown, in this embodiment, the fault point where the cable has an insulation breakdown fault is point G, point A is the point on the shielding layer 3 corresponding to point G, and points B, C, and D are sampling points extending from one side of point A. As can be seen from the figure, with point G as the center, as the distance from point G increases, the potential difference between the shielding layer and the core 1 of the cable gradually decreases until it is zero, and the potential difference at the fault point G is the highest, and the voltage relationship is UA0>UB0>UC0>UD0. At this time, the copper core 1 of the cable discharges to the shielding layer through the fault point G (at this time, only the core 1 discharges to the shielding layer, but no insulation breakdown fault occurs). Although the main insulation has not been broken down at this time, there is voltage, which is connected to the cable braid through the shielding layer and connected to the ground, forming a current path.

[0109] At this time, the above current is collected by the Rogowski coil, collected by the current standby unit, converted into a voltage signal after integration of the integral signal composed of resistors, capacitors and amplifiers, and collected by the voltage collection unit, and then output to the data analysis terminal after passing through the analog-to-digital conversion module, the communication management machine and the switch. A filter circuit is set in the current collection unit to remove external stray signals and filter the current signal output by the Rogowski coil. Figure 5 This is the current waveform output by the shielding layer 3 when a fault occurs. After being collected by the Rogowski coil, the current waveform output by the Rogowski coil is as follows: Figure 6 As shown in the figure, the i-th abnormal current waveform extracted from the induced current data and the time t1 when it appears, and the i+1-th abnormal current waveform with the same current direction extracted from the induced current data and the time t1 when it appears 2， And calculate the time difference between the two abnormal current waveforms as Δt i .

[0110] The induced voltage data and induced current data sent by the data transmission system are acquired through the data analysis terminal, and the discharge position of the shielding layer 3 is calculated according to the induced current data, thereby determining the fault position of the cable.

[0111] The present invention monitors the induced current of the shielding layer 3 at the grounding point through an AC current sensor; collects the induced voltage data of the AC current sensor through a voltage acquisition system; collects the induced current data of the AC current sensor through a current acquisition system; transmits the induced voltage data collected by the voltage acquisition system and the induced current data collected by the current acquisition system to a data analysis terminal through a data transmission system; obtains the induced voltage data and induced current data sent by the data transmission system through the data analysis terminal, calculates the discharge position of the shielding layer 3 according to the induced current data, and then determines the fault position of the cable. In this way, the insulation performance of the high-voltage cable is monitored in real time, and the insulation breakdown fault of the high-voltage cable is accurately predicted. The fault point can be quickly and accurately located, and the fault position can be found before the insulation layer of the high-voltage cable breaks down. The fault position is quickly located through fault ranging, and the fault position is found and handled in time. This is to prevent the insulation breakdown from continuing to develop to form a ground short circuit fault, affecting the safe operation of the production equipment, and avoiding production losses and personal injuries.

[0112] The present invention performs insulation detection on the cable to check whether the cable has weak insulation and judge whether the cable insulation is qualified.

[0113] When leakage current is detected, the data analysis terminal is used to analyze and determine whether it is an abnormal current waveform. If not, it is eliminated. If it is, the current waveform is analyzed, and the fault point is measured by traveling wave, and the location of the partial discharge point is obtained according to the distance measured. The fault analysis system pops up a window to notify the operation and maintenance personnel to eliminate the hidden dangers. The whole process is handled before it develops into a fault, avoiding accidents and reducing economic losses to the country and enterprises.

[0114] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A high voltage cable online fault monitoring system, characterized in that: include: A cable, comprising at least one wire core and shielding layers respectively arranged around each wire core; One end of the wire core is connected to a power source, and the other end is connected to a terminal power load; The shielding layer is grounded at one end close to the power supply; an insulating layer is provided between the shielding layer and the wire core; The fault monitoring system also includes an AC current sensor, a voltage acquisition system, a current acquisition system, a data transmission system and a data analysis terminal; The AC current sensor is used to monitor the induced current of the shielding layer at the grounding point; The voltage acquisition system is used to collect the induced voltage data of the AC current sensor; The current acquisition system is used to collect induced current data of the AC current sensor; The data transmission system is used to transmit the induced voltage data collected by the voltage collection system and the induced current data collected by the current collection system to the data analysis terminal; The data analysis terminal is used to obtain the induced voltage data and the induced current data sent by the data transmission system, calculate the discharge position of the shielding layer according to the induced current data, and then determine the fault position of the cable.

2. A high voltage cable online fault monitoring system according to claim 1, characterized in that: The AC current sensor is a Rogowski coil.

3. A high voltage cable online fault monitoring system according to claim 2, characterized in that: The voltage acquisition system includes a resistor, a capacitor, an amplifier and a voltage acquisition unit; The first output end of the Rogowski coil is connected to one end of the resistor, and the other end of the resistor is connected to one end of the capacitor and the inverting input end of the amplifier respectively; The second output end of the Rogowski coil is connected to the in-phase input end of the amplifier and the second input end of the voltage acquisition unit respectively; The output end of the amplifier is connected to the other end of the capacitor and the first input end of the voltage acquisition unit.

4. A high voltage cable online fault monitoring system according to claim 3, characterized in that: The current collection system comprises a current collection unit; The first end of the current collection unit is connected to the second output end of the Rogowski coil; The second end of the current acquisition unit is connected to the in-phase input end of the amplifier and the second input end of the voltage acquisition unit.

5. A high voltage cable online fault monitoring system according to claim 4, characterized in that: The data transmission system includes an analog-to-digital conversion module and a communication management machine; The output end of the current acquisition unit is connected to the first input end of the analog-to-digital conversion module; The output end of the voltage acquisition unit is connected to the second input end of the analog-to-digital conversion module; The output end of the analog-to-digital conversion module is connected to the input end of the communication management machine; The output end of the communication management machine is connected to the data analysis terminal.

6. A high voltage cable online fault monitoring system according to claim 5, characterized in that: The data transmission system also includes a switch; The output end of the communication management machine is connected to the first end of the switch; the second end of the switch is connected to the data analysis terminal.

7. A high voltage cable online fault monitoring system according to claim 1, characterized in that: The shielding layer is a metal shielding layer.

8. A method for online fault monitoring of a high-voltage cable, applied to a data analysis terminal as claimed in any one of claims 1 to 7, characterized in that: Methods include: Acquiring the induced current data sent by the data transmission system; Extract the ith abnormal current waveform and the (i+1)th abnormal current waveform having the same current direction as the ith abnormal current waveform from the induced current data, and calculate the time difference Δt between the two abnormal current waveforms i ; Wherein, i is an integer greater than 0; According to formula 1 Calculate the mean of the time difference Where n is the time difference Δt between the ith abnormal current waveform and the (i+1)th abnormal current waveform with the same current direction as the ith abnormal current waveform i Total number of; According to formula 2 Calculate the distance L between the discharge position of the shielding layer and the AC current sensor, where V is the propagation speed of the current in the shielding layer; The distance L between the discharge position of the shielding layer and the AC current sensor is taken as the distance between the fault position of the cable and the AC current sensor.

9. A high voltage cable online fault monitoring method according to claim 8, characterized in that: After taking the distance L between the discharge position of the shielding layer and the AC current sensor as the distance between the fault position of the cable and the AC current sensor, the method further comprises: Generates an alarm signal and outputs the distance between the fault location of the cable and the AC current sensor.

10. A high voltage cable online fault monitoring method according to claim 8, characterized in that: After acquiring the induced current data sent by the data transmission system, the method further includes: Acquire induced voltage data sent by a data transmission system; Outputs the induced current data and induced voltage data.

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