CN115483651A - Cable tapping system, method and device for determining cable state - Google Patents

Abstract

The invention discloses a cable tapping system, a method and a device for determining the state of a cable, wherein the system comprises: the first cable distribution box comprises a first bus and a first current transformer; the three-phase branch line is integrated into a second main cable at the outgoing line side; the second cable distribution box is connected with a three-phase branch line branched from a second main cable entering from the outside, and a second current transformer positioned on the wire inlet side of the second cable distribution box is used for measuring a second current vector of the three-phase branch line; the second current vector and the first current vector are used for determining the electric energy transmission state between the first current transformer and the second current transformer. This scheme can be with the scope location that breaks down in the current collection circuit between two adjacent cable distribution boxes to the scope of troubleshooting has been dwindled greatly, has reduced maintenance work load, has shortened the repair cycle of salvageing, makes the circuit that breaks down can resume the power supply fast.

Description

Cable tapping system, method and device for determining cable state

Technical Field

The invention relates to the field of power equipment, in particular to a cable tapping system, a method and a device for determining a cable state.

Background

With the large-scale development and construction of new energy stations, cable collecting circuits are increasingly used in special environments such as high wind speed, repeated icing, tourist landscape requirements and the like. When a fault occurs in the power collecting line, the circuit breaker is tripped by a protection device installed at the circuit breaker to isolate the fault. However, one of the current collecting lines is tripped, which causes the whole current collecting line to be tripped. Thus requiring the inspector to locate the source of the trip fault.

In the prior art, a cable in a new energy field area has a fault, and an inspector segments the cable in a current collection line through an insulation megger and then manually measures the segmented cable to locate the fault range. For example, the joint position and a certain section of cable, especially the joint position, are weak links that are known to be prone to faults, and faults in these places can cause tripping of the whole current collecting line. The cable fault finding method is low in speed, large in overhauling workload and long in repair and restoration cycle, and is not beneficial to quick recovery of power supply of a current collection circuit.

Disclosure of Invention

The invention provides a cable tapping system, a method and a device for determining a cable state, and solves the problems of low cable fault finding speed, large overhauling workload and long repair and restoration cycle.

In order to achieve the purpose, the invention adopts the following technical scheme:

in a first aspect, the present invention provides a cable breakout system, comprising at least a first cable breakout box and a second cable breakout box, the first cable breakout box comprising a first bus, a first current transformer and a first cable joint;

the first bus is positioned in an inner cavity of the first cable distribution box and used for converging a first three-phase branch line separated from a first main cable entering from the outside and forming a second three-phase branch line after converging;

the first end of the first current transformer is used for connecting a second three-phase branch circuit which penetrates out after the first bus is converged and measuring a first current vector of the second three-phase branch circuit;

the first cable joint is used for connecting a second three-phase branch line penetrating out of the second end of the first current transformer; the second three-phase branch line is integrated into a second main cable at the outlet side of the first cable distribution box; the second main cable is an output cable of the first cable distribution box;

the second cable joint positioned on the wire inlet side of the second cable distribution box is used for connecting a third three-phase branch line branched from a second main cable entering from the outside, and the second current transformer positioned on the wire inlet side of the second cable distribution box is used for measuring a second current vector of the third three-phase branch line;

the second current vector and the first current vector are used to determine a power transfer state between the first current transformer and the second current transformer.

In one possible implementation manner, the first current transformers are single-phase current transformers, the number of the first current transformers is three, and the three first current transformers are respectively used for connecting the second three-phase branch line and respectively used for measuring three-phase currents of the second three-phase branch line; the number of the first buses is three, and the first buses are respectively used for connecting three first current transformers.

In one possible implementation manner, the first end of the first current transformer is connected with the first bus through a copper bar; the second end of the first current transformer is connected with the first cable connector through a copper bar.

In one possible implementation, the first cable distribution box further includes a third cable joint and a third current transformer; the third cable joint is positioned on the wire inlet side of the first cable distribution box and used for connecting a first three-phase branch line which enters from the outside and is branched from the first main cable; the first end of the third current transformer is used for connecting a first three-phase branch line penetrating out of the first cable joint and measuring a current vector of the first three-phase branch line; and the second end of the third current transformer is used for connecting the first bus.

In one possible implementation, the first cable distribution box may further include a fourth cable joint and a fourth current transformer; the fourth cable joint is positioned on the wire inlet side of the first cable distribution box and used for connecting a fourth three-phase branch line branched from a third main cable entering from the outside; the first end of the fourth current transformer is used for connecting a fourth three-phase branch line through which a fourth cable joint penetrates out, and measuring a current vector of the fourth three-phase branch line; the second end of the fourth current transformer is connected with the first bus and is used for the fourth three-phase branch line to converge on the first bus; the second three-phase branch line may be formed by joining a first three-phase branch line branched from the first main cable and a fourth three-phase branch line branched from the third main cable to the bus bar.

In one possible implementation, the first cable breakout box may further include a fifth cable joint and a fifth current transformer; the first end of the fifth current transformer is used for connecting a fifth three-phase branch line which penetrates out after a first three-phase branch line which enters from the outside and is branched from a first main cable passes through a first bus and converges, and measuring a first current vector of the fifth three-phase branch line; the fifth cable joint is positioned on the outgoing line side of the first cable distribution box and used for connecting a fifth three-phase branch line penetrating out of the second end of the fifth current transformer; the fifth three-phase branch line is gathered into a fourth main cable on the outlet side of the first cable tapping box; the fourth main cable is an output cable of the first cable distribution box;

in a possible implementation manner, the second cable distribution box further comprises a second bus, a sixth current transformer and a sixth cable joint, a second three-phase branch line branched from a second main cable entering from the outside is converged by the second bus and then penetrates out of the sixth three-phase branch line, and the sixth three-phase branch line passes through the sixth current transformer and the sixth cable joint and then is integrated into a fifth main cable, and the fifth main cable is used for penetrating out of the second cable distribution box and then is connected with the electric equipment; the sixth current transformer is located between the second bus and the sixth cable joint, and is used for measuring a third current vector of a sixth three-phase branch line between the second bus and the sixth cable joint, and the third current vector is used for determining a cable state between the sixth current transformer and the electric equipment.

In a second aspect, the present invention provides a method for determining a cable status, which is applied to the processing module of the cable tapping system in the first aspect, and the system further includes a first cable tapping box and a second cable tapping box, where the first cable tapping box includes a first bus bar, a first current transformer and a first cable joint, and the second cable tapping box includes a second current transformer, and the method includes: obtaining a first current vector from a first current transformer, the first current vector comprising: the second three-phase branch line is converged out by the first bus and is collected as a second main cable at the wire outlet side through the first current transformer and the first cable joint; obtaining a second current vector from a second current transformer, the second current vector comprising: a second current value and a second current direction of a third three-phase branch cable branched from a second main cable positioned in a second cable branching box; the second main cable is an output cable of the first cable distribution box and is connected with the second cable distribution box; based on the first current vector and the second current vector, a power transfer state between the first current transformer and the second current transformer is determined.

In one possible implementation, determining a power transfer state between the first current transformer and the second current transformer based on the first current vector and the second current vector includes: determining whether the first current direction and the second current direction are the same; if the first current transformer and the second current transformer are the same, determining that the cable state between the first current transformer and the second current transformer is a fault state; and if not, determining that the cable state between the first current transformer and the second current transformer is a normal state.

In a possible implementation manner, after determining that the power transmission state between the first current transformer and the second current transformer is a fault state, the method further includes: determining an absolute value of the sum of the first current vector and the second current vector to obtain an action current value; determining an absolute value of a difference between the first current vector and the second current vector to obtain a braking current value; if the action current is larger than the braking current, the protection action is started.

In a third aspect, the present invention further provides a device for determining a cable status, which is applied to the processing module of the cable tapping system in the first aspect, the system further includes a first cable tapping box and a second cable tapping box, the first cable tapping box includes a first bus bar, a first current transformer and a first cable joint, the second cable tapping box includes a second current transformer, and the device includes:

a first current vector obtaining module, configured to obtain a first current vector from the first current transformer, where the first current vector includes: a first current value and a first current direction flowing through the second three-phase branch line of the first current transformer; the second three-phase branch line penetrates out of the first bus after converging, passes through the first current transformer and the first cable joint and is gathered as a second main cable on the outlet side;

a second current vector obtaining module, configured to obtain a second current vector from the second current transformer, where the second current vector includes: a second current value and a second current direction of a third three-phase branch cable branched from a second main cable located in the second cable branching box; the second main cable is an output cable of the first cable distribution box and is connected with the second cable distribution box;

a power transfer state determination module configured to determine a power transfer state between the first current transformer and the second current transformer based on the first current vector and the second current vector.

The invention has the following beneficial effects:

the invention provides a cable tapping system and a method for determining a cable state, wherein a first current transformer is arranged at the outlet side of a first cable tapping box, a second current transformer is arranged at the inlet side of a second cable tapping box and is respectively used for measuring the current vector of a three-phase branch line of a second main cable at the outlet side of the first cable tapping box and the current vector of the three-phase branch line at the inlet side of the second cable tapping box, and the fault range in a current collecting line can be positioned between two adjacent cable tapping boxes by judging the electric energy transmission state between the first current transformer and the second current transformer, so that the fault finding range is greatly reduced, the overhauling workload is reduced, the rush repair cycle is shortened, and the power supply of the fault line can be quickly recovered.

Drawings

Fig. 1 is a schematic partial structural diagram of a current collecting circuit of a cable tapping system according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram of a cable tapping system according to an embodiment of the present invention;

fig. 3 is a front view of a cable breakout box for a cable breakout system according to an embodiment of the present invention;

fig. 4 is a side view of a cable breakout box for a cable breakout system according to an embodiment of the present invention;

fig. 5 is a top view of a cable breakout box for a cable breakout system according to an embodiment of the present invention;

fig. 6 is an electrical schematic of a cable breakout box for a cable breakout system according to an embodiment of the present invention;

FIG. 7 is a flow chart illustrating steps of a method for determining a cable condition according to an embodiment of the present invention;

fig. 8 is a block diagram of an apparatus for determining a cable status according to an embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without inventive step based on the embodiments of the present invention, are within the scope of protection of the present invention.

In the following, the terms "first", "second" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the embodiments of the present disclosure, "a plurality" means two or more unless otherwise specified. In addition, the use of "based on" or "according to" is meant to be open and inclusive in that a process, step, calculation, or other action that is "based on" or "according to" one or more stated conditions or values may, in practice, be based on additional conditions or exceed the stated values.

In order to solve the problems that a cable path in a current collecting line is long, branches are multiple, and a traditional overhauling method is long in time consumption and high in loss when a fault occurs, the embodiment of the invention provides a cable tapping system.

Fig. 1 is a partial schematic diagram of a current collection circuit using a cable tapping system.

As shown in fig. 1, during the process of transmitting electric energy on the power collecting line, a plurality of cable distribution boxes are often required to be arranged to perform distribution and connection on the cable line. When a fault occurs in the electric energy transmission process of a collecting line, the application provides a cable tapping system.

Fig. 2 is a schematic structural diagram of a cable tapping system according to an embodiment of the present invention.

As shown in fig. 2, a cable breakout system comprises at least a first cable breakout box 10 and a second cable breakout box 20, the first cable breakout box 10 comprising a first busbar 103, a first current transformer 102 and a first cable joint 101.

Fig. 3 is a front view of a cable breakout box for a cable breakout system according to an embodiment of the present invention.

The cable distribution box in fig. 3 may be the first cable distribution box 10. The first bus 103 is located in an inner cavity of the first cable distribution box 10, and is used for converging a first three-phase branch line branched from a first main cable 11 entering from the outside and forming a second three-phase branch line after the converging; the first current transformer 102 is located on the outgoing line side of the first cable distribution box 10, and a first end of the first current transformer 102 is used for connecting a second three-phase branch line which penetrates out after the first bus 103 converges and measuring a first current vector of the second three-phase branch line; the first cable joint 101 is used for connecting a second three-phase branch line which penetrates out of the second end of the first current transformer 102; the second three-phase branch line is integrated into a second main cable 12 at the outlet side of the first cable distribution box 10; the second main cable 12 is an output cable of the first cable distribution box 10.

A second cable joint 201 at the incoming side of the second cable distribution box 20 is used for connecting a third three-phase branch line branched from the second main cable 12 entering from the outside, and a second current transformer 202 at the incoming side of the second cable distribution box 20 is used for measuring a second current vector of the third three-phase branch line; the second current vector and the first current vector are used to determine a power transfer state between the first current transformer 102 and the second current transformer 202.

Specifically, the first cable distribution box and the second cable distribution box are the cable distribution box 10 and the cable distribution box 20 in fig. 1, respectively. A first current vector of a second three-phase branch line is obtained by obtaining a first current transformer 102 at the outgoing side of the first cable distribution box 10 for measurement, and a second current vector obtained by obtaining a second current transformer 202 at the incoming side of the second cable distribution box 20 adjacent to the first cable distribution box 10 for measurement.

The second three-phase branch line is integrated as a second main cable 12 at the outgoing side of the first junction box, so that the second main cable 12 is an output cable of the first cable junction box 10; the second main cable 12 enters the second cable distribution box and is branched into a third three-phase branch line, so that the second main cable 12 is an input cable of the second cable distribution box 20.

Since the second three-phase branch line and the third three-phase branch line branched from the second main cable 12 are connected to the first current transformer 102 through the first cable joint 101, respectively, the second cable joint 201 is connected to the second current transformer 202. The power transmission state between the first current transformer 102 and the second current transformer 202 is determined based on the first current vector and the second current vector. I.e. determining whether the second main cable 12 and the first cable connector 101 and the first cable connector 201 connected to the second main cable 12 are electrically failed.

The fault range in the current collecting line is positioned to the second main cable 12 between two adjacent cable distribution boxes and the first cable connector 101 and the first cable connector 201 connected with the second main cable 12, so that the fault finding range is greatly reduced. This system can be in the electric energy transmission process, and when cable and cable joint broke down, the very first time detects through the change of current vector, improves the efficiency of the maintenance of current collection circuit greatly.

In a possible implementation manner, the first current transformers 102 are single-phase current transformers, the number of the first current transformers 102 is three, and the three first current transformers 102 are respectively used for connecting to the second three-phase branch line and are respectively used for measuring three-phase currents of the second three-phase branch line; the number of the first bus bars 103 is three for connecting the first three-phase branch lines.

Specifically, the cables in the current collecting line are three-phase cables, that is, the first main cable 11 and the second main cable 12 are both three-phase cables, and the three-phase cables are branched into three-phase branch lines, which are respectively an a-phase cable, a B-phase cable, and a C-phase cable. The A-phase current transformer measures a current vector of the A-phase cable, the B-phase current transformer measures a current vector of the B-phase cable, and the C-phase current transformer measures a current vector of the C-phase cable. The difference between the three phases is 120 degrees, specifically, the phase B lags behind the phase A by 120 degrees, and the phase C lags behind the phase B by 120 degrees.

Illustratively, fig. 4 is a side view of a cable breakout box for a cable breakout system according to an embodiment of the present invention. As can be visually observed by referring to fig. 4, the first current transformers 102 are three, namely, an a-phase current transformer, a B-phase current transformer, and a C-phase current transformer.

Fig. 5 is a top view of a cable distribution box for a cable distribution system according to an exemplary embodiment of the present invention. Referring to fig. 5, it can be visually observed that the number of the first bus bars 103 is 3, which are respectively an a-phase bus bar, a B-phase bus bar, and a C-phase bus bar. The branch circuits corresponding to the A-phase cable, the B-phase cable and the C-phase cable are respectively connected with the branch circuits corresponding to the A-phase cable, the B-phase cable and the C-phase cable.

In a possible implementation manner, a first end of the first current transformer 102 is connected with the first bus 103 through a copper bar 104; the second end of the first current transformer 102 is connected to the first cable connector 101 by copper bar.

The copper bar has the loss little, and the characteristics that intensity is high can bear great electric current, therefore the preferred copper bar that adopts of this embodiment is connected.

Referring to fig. 4, the first current transformer 102 includes an a-phase current transformer, a B-phase current transformer, and a C-phase current transformer, which are respectively connected to the a-phase bus, the B-phase bus, and the C-phase bus of the first bus 103 through copper bars. The number of the first cable connectors 101 is also three, and the first cable connectors are respectively connected with the phase current transformer A, the phase current transformer B and the phase current transformer C through copper bars.

In one possible implementation, the first cable distribution box 10 further includes a third cable joint and a third current transformer; a third cable joint, located at the incoming side of the first cable distribution box 10, for connecting a first three-phase branch line branched from a first main cable 11 entering from the outside; the first end of the third current transformer is used for connecting a first three-phase branch line which penetrates out of the first cable joint 101 and measuring a current vector of the first three-phase branch line; the second end of the third current transformer is used for connecting the first bus bar 103.

Under general conditions, cable routing in a current collection circuit is complex, and the number of branches is large, so that a cable distribution box is often needed to perform distribution and connection. When the current collecting line needs to be tapped and connected, the tapping and connection of the cable tapping box can be divided into one inlet and two outlets, two inlets and one outlet, three inlets and one outlet, two inlets and two outlets and the like according to the number of the input cables and the output cables, and the tapping and connection of the cable tapping box are performed according to actual needs, and are not limited to the enumeration.

Fig. 4 is a side view of a structure of an incoming and outgoing cable distribution box, and since the paths of the incoming cable first main cable 11 and the outgoing cable second main cable 12 are the same, fig. 4 shows the connection relationship of the outgoing cables, but can be used as a reference drawing of the incoming cable first main cable 11.

Referring to fig. 4, the first main cable 11 entering from the outside branches a first three-phase branch line including an a-phase cable, a B-phase cable, and a C-phase cable at the incoming side of the first junction box 10, and is connected to three third cable joints in the first cable box, respectively. The first branch line passes through the third cable joint, flows through the copper bar, reaches the third current transformer, then passes through the copper bar again, reaches the first bus 103 connected with the third current transformer, and finally the first branch line converges at the first bus 103.

The cable distribution box with one inlet and one outlet in the current collection line has a connection function, and generally when the cable distribution box is applied to a 35kV current collection line, connection is carried out when the length of the cable exceeds 400m or when the cable passes through a pond, a cross road or other complex road sections.

In one possible implementation, the first cable distribution box 10 may further include a fourth cable joint and a fourth current transformer; a fourth cable joint, which is located at the wire inlet side of the first cable distribution box 10 and is used for connecting a fourth three-phase branch line from which a third main cable enters from the outside is branched; the fourth current transformer is positioned on the wire inlet side of the first cable distribution box 10, and the first end of the fourth current transformer is used for connecting a fourth three-phase branch line through which a fourth cable joint penetrates out and measuring a current vector of the fourth three-phase branch line; the second end of the fourth current transformer is connected with the bus and is used for the fourth three-phase branch line to converge on the bus; the second three-phase branch line may be formed by merging a first three-phase branch line branched from the first main cable 11 and a fourth three-phase branch line branched from the third main cable.

Fig. 6 is an electrical schematic diagram of a cable breakout box for a cable breakout system according to an embodiment of the present invention.

Referring to fig. 6, specifically to an electrical diagram of a two-in one-out cable distribution box, a fourth cable connector and a fourth current transformer are disposed on the inlet side of the first distribution box 10, and are used for connecting a third main cable entering from the outside, a fourth three-phase branch line branched from the third main cable and a first three-phase branch line branched from the first main cable 11 entering from the outside converge to the first bus 103 through the cable connectors and the current transformers, respectively, and form a second three-phase branch line after converging. The third main cable and the first main cable are input cables of the two-in one-out cable distribution box, and the second main cable is an output cable of the two-in one-out cable distribution box.

In one possible implementation, the first cable breakout box 10 may further include a fifth cable joint and a fifth current transformer; the first end of the fifth current transformer is used for connecting a fifth three-phase branch line, which is formed by converging a first three-phase branch line separated from a first main cable 11 entering from the outside through a first bus 103 and passing out, and measuring a first current vector of the fifth three-phase branch line; the fifth cable joint is located on the outgoing side of the first cable distribution box 10 and used for connecting a fifth three-phase branch line penetrating out of the second end of the fifth current transformer; the fifth three-phase branch line is integrated into a fifth main cable at the outlet side of the first cable distribution box 10; the fifth main cable is an output cable of the first cable distribution box 10;

when the cable distribution box is a cable distribution box with one inlet and two outlets, the first main cable 11 entering from the outside is an input cable, the three-phase branch lines separated from the input cable form a second three-phase branch line and a fifth three-phase branch line after being converged by a bus, and the second three-phase branch line and the fifth three-phase branch line are respectively integrated into a second main cable 12 and a fifth main cable on the outlet side after respectively passing through the current transformer and the cable joint.

In a possible implementation manner, the second cable distribution box 20 further includes a second bus 203, a sixth current transformer and a sixth cable joint, a second three-phase branch line branched from the second main cable 12 entering from the outside is converged by the second bus 203, and then the sixth three-phase branch line penetrating out passes through the sixth current transformer and the sixth cable joint and is integrated into a fifth main cable, and the fifth main cable is used for penetrating out from the second cable distribution box 20 and then is connected to the electric device; the sixth current transformer is located between the second bus bar 203 and the sixth cable joint, and the sixth current transformer is used for measuring a third current vector of a sixth three-phase branch line between the second bus bar 203 and the sixth cable joint, and the third current vector is used for determining an electric energy transmission state between the sixth current transformer and the electric equipment.

When the power collecting line transmits electric energy to electric equipment, the output cable of the cable tapping box is connected with the electric equipment. When the fifth main cable of the output cable in the second cable distribution box 20 is connected to the electric device, the sixth current transformer is used for measuring the sixth three-phase branch line, and the fifth main cable corresponds to the sixth three-phase branch line, so that the measured third current vector of the sixth three-phase branch line is used for determining the electric energy transmission state between the sixth current transformer and the electric device.

Still can also generally set up other subassemblies according to actual conditions in the cable tapping box, like protection device, generally be used for obtaining the current vector of current transformer in the tapping box to upload terminal carries out data analysis and processing, and sends the fault information that obtains the analysis for the user, and the user overhauls the current collection circuit according to fault information.

Fig. 7 is a flowchart illustrating steps of a method for determining a cable status according to an embodiment of the present invention.

As shown in fig. 7, the method is applied to the processing module of the cable tapping system, the system further comprises a first cable tapping box and a second cable tapping box, the first cable tapping box comprises a first bus bar, a first current transformer and a first cable joint, the second cable tapping box comprises a second current transformer, the method comprises the following steps:

step 101, obtaining a first current vector from the first current transformer, where the first current vector includes: a first current value and a first current direction flowing through a second three-phase branch line of the first current transformer; and the second three-phase branch line penetrates out of the first bus after converging and is collected as a second main cable on the outgoing line side through the first current transformer and the first cable joint.

The protection device in the first cable box 10 obtains the first current vector measured by the first current transformer 102 and sends the first current vector to the computer terminal device.

102, obtaining a second current vector from the second current transformer, where the second current vector includes: a second current value and a second current direction of a third three-phase branch cable branched from a second main cable located in the second cable branching box; the second main cable is an output cable of the first cable distribution box and is connected with the second cable distribution box.

The protection device in the second cable box 20 obtains the second current vector measured by the second current transformer 202, and sends the second current line to the computer terminal device.

Step 103, determining the power transmission state between the first current transformer 102 and the second current transformer 202 based on the first current vector and the second current vector.

The computer terminal obtains current vectors measured by the current transformers in the cable distribution boxes, and determines the electric energy transmission state between the first current transformer 102 and the second current transformer 202 through analysis processing of the current vectors.

Since the second three-phase branch line and the third three-phase branch line branched from the second main cable 12 are connected to the first current transformer 102 through the first cable joint 101, respectively, the second cable joint 201 is connected to the second current transformer 202. The power transmission state between the first current transformer 102 and the second current transformer 202 is determined based on the first current vector and the second current vector. I.e. determining whether the second main cable 12 and the first cable connector 101 and the first cable connector 201 connected to the second main cable 12 are electrically failed.

In summary, the power transmission states between the first current transformer 102 and the second current transformer 102 are the second main cable 12 connecting the first cable distribution box 10 and the second cable distribution box 20, the first cable connector 101 in the first distribution box 10 connected to the second main cable 12, and the second cable connector 201 in the second cable distribution box 20 connected to the second main cable 12. That is, obtaining the first current vector and the second current vector can determine that the power transmission state of the second main cable 12 and the first cable joint 101 and the second cable joint 201 is normal or faulty. Therefore, the fault range is accurately positioned, and the cable and the related equipment are timely repaired, so that the power supply of the line with the fault can be quickly recovered.

In one possible implementation, step 103 includes the following steps 1031-1033:

step 1031 of determining whether the first current direction and the second current direction are the same;

step 1032, if the two current transformers are the same, determining that the electric energy transmission state between the first current transformer 102 and the second current transformer 202 is a fault state;

step 1033, if the two current transformers are different, determining that the electric energy transmission state between the first current transformer 102 and the second current transformer 202 is a normal state.

In steps 1031 to 1033, since the cable in the current collecting line is a three-phase cable, the current in the three-phase cable is an alternating current, and the current direction of the alternating current is changed regularly, that is, the current phase has a certain regularity. The judgment method is to define the direction of the current passing out after the bus bars are converged as the positive direction, so that the first current transformer 102 measures the second three lines passing out after the first bus bars 103 in the first cable box 10 are converged, and the first current is the positive direction in the normal power transmission process. The second current transformer 202 is a third branch line branched from the second main cable 12 which is converged to the second bus 203, so that the second current direction is opposite during normal power transmission. Therefore, if the first current direction and the second current direction are different, it is determined that the power transmission state between the first current transformer 102 and the second current transformer 202 is a normal state.

Before a fault occurs, the current states detected by the first current transformer 102 and the second current transformer 202 may change, and specifically, the direction of the first current may be the same as the direction of the second current, so that when the first current direction is the same as the second current direction, it is determined that the power transmission state between the first current transformer 102 and the second current transformer 202 is a normal state.

In a possible implementation manner, after determining that the power transmission state between the first current transformer and the second current transformer is a fault state, the method further includes steps 201 to 203:

step 201, determining an absolute value of a sum of the first current vector and the second current vector to obtain an action current value;

step 202, determining an absolute value of a difference between the first current vector and the second current vector to obtain a braking current value;

and 203, if the action current value is larger than the brake current value, starting a protection action. Other components, such as a power supply, a lightning arrester, a live display lamp and a protection device with a circuit breaker, are generally arranged in the cable tapping box according to actual conditions.

In steps 201 to 203, since the detection object corresponding to the first current vector is the current vector of the three branch lines of the second main cable 12 in the first cable box 10, and the detection object corresponding to the second current vector is the current vector of the three branch lines of the second main cable 12 in the second cable box 20, the magnitude of the first current vector is equal to that of the second current vector, and the direction of the first current vector is opposite to that of the second current vector, if the loss is not counted, during the power transmission. Therefore, when the power transmission is normal, the action current has a value of zero, and the braking current is twice as large as the first current vector or the second current vector.

Therefore, when the power transmission is normal, the action current is far smaller than the brake current. When the action current is larger than the braking current, the electric energy transmission is in fault, so that a circuit breaker in the protection device is required to cut off the circuit to avoid the loss of a current collection circuit in a larger range.

Fig. 8 is a block diagram of an apparatus for determining a cable status according to an embodiment of the present invention.

As shown in fig. 8, the apparatus is applied to the processing module of the cable branching system according to the first aspect, the system further includes a first cable branching box and a second cable branching box, the first cable branching box includes a first bus bar, a first current transformer and a first cable joint, the second cable branching box includes a second current transformer, and the apparatus includes:

a first current vector obtaining module 301, configured to obtain a first current vector from the first current transformer, where the first current vector includes: a first current value and a first current direction flowing through the second three-phase branch line of the first current transformer; the second three-phase branch line penetrates out of the first bus after converging, passes through the first current transformer and the first cable joint and is integrated into a second main cable on the outlet side;

a second current vector obtaining module 302, configured to obtain a second current vector from the second current transformer, where the second current vector includes: a second current value and a second current direction of a third three-phase branch cable branched from a second main cable located in the second cable breakout box; the second main cable is an output cable of the first cable distribution box and is connected with the second cable distribution box;

a power transmission state determining module 303, configured to determine a power transmission state between the first current transformer and the second current transformer based on the first current vector and the second current vector.

It can be clearly understood by those skilled in the art that, for convenience and simplicity of description, the specific working processes of the above-described systems, apparatuses and units may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again.

In yet another embodiment provided by the present invention, an apparatus is also provided, which includes a processor and a memory having stored therein at least one instruction, at least one program, a set of codes, or a set of instructions, which is loaded and executed by the processor to implement the method of linear fitting of point cloud data described in the embodiments of the present invention.

In yet another embodiment provided by the present invention, a computer readable storage medium is further provided, in which at least one instruction, at least one program, a set of codes, or a set of instructions is stored, and the at least one instruction, the at least one program, the set of codes, or the set of instructions is loaded and executed by a processor to implement the method for linear fitting of point cloud data described in the embodiment of the present invention.

In the above embodiments, all or part of the implementation may be realized by software, hardware, firmware, or any combination thereof. When implemented in software, it may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When loaded and executed on a computer, cause the processes or functions described in accordance with the embodiments of the invention to be performed in whole or in part. The computer may be a general purpose computer, a special purpose computer, a network of computers, or other programmable device. The computer instructions may be stored in a computer readable storage medium or transmitted from one computer readable storage medium to another, for example, from one website site, computer, server, or data center to another website site, computer, server, or data center via wired (e.g., coaxial cable, fiber optic, digital Subscriber Line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.). The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device, such as a server, a data center, etc., that includes one or more available media. The usable medium may be a magnetic medium (e.g., floppy Disk, hard Disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium (e.g., solid State Disk (SSD)), among others.

It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrases "comprising a," "8230," "8230," or "comprising" does not exclude the presence of additional like elements in a process, method, article, or apparatus that comprises the element.

All the embodiments in the present specification are described in a related manner, and the same and similar parts among the embodiments may be referred to each other, and each embodiment focuses on the differences from the other embodiments. In particular, as for the system embodiment, since it is substantially similar to the method embodiment, the description is relatively simple, and reference may be made to the partial description of the method embodiment for relevant points.

The above description is only for the preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention shall fall within the protection scope of the present invention.

The above description is only an embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions within the technical scope of the present invention are included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the appended claims.

Claims (10)

1. A cable tapping system is characterized by at least comprising a first cable tapping box and a second cable tapping box, wherein the first cable tapping box comprises a first bus, a first current transformer and a first cable joint;

the first bus is positioned in an inner cavity of the first cable distribution box and used for converging a first three-phase branch line branched from a first main cable entering from the outside and forming a second three-phase branch line after converging;

the first current transformer is positioned on the outgoing line side of the first cable distribution box, and the first end of the first current transformer is used for connecting a second three-phase branch line which penetrates out after the first bus is converged and measuring a first current vector of the second three-phase branch line;

the first cable joint is used for connecting the second three-phase branch line penetrating out of the second end of the first current transformer; the second three-phase branch line is integrated into a second main cable at the outlet side of the first cable tapping box; the second main cable is an output cable of the first cable distribution box;

the second cable joint positioned on the wire inlet side of the second cable distribution box is used for connecting a third three-phase branch line branched from the second main cable entering from the outside, and the second current transformer positioned on the wire inlet side of the second cable distribution box is used for measuring a second current vector of the third three-phase branch line;

the second current vector and the first current vector are used to determine a power transfer state between the first current transformer and the second current transformer.

2. The system of claim 1, wherein:

the three first current transformers are respectively used for connecting the second three-phase branch line and respectively used for measuring the three-phase current of the second three-phase branch line;

the number of the first buses is three, and the three first buses are respectively used for connecting the three first current transformers.

3. The system of claim 1, wherein the first cable breakout box further comprises a third cable connector and a third current transformer;

the third cable joint is positioned on the wire inlet side of the first cable distribution box and used for connecting a first three-phase branch line which enters from the outside and is branched from the first main cable;

the third current transformer is located on the wire inlet side of the first cable tapping box, and the first end of the third current transformer is used for connecting the first three-phase branch line penetrating out of the first cable connector and measuring the current vector of the first three-phase branch line; and the second end of the third current transformer is used for connecting the first bus.

4. The system of claim 1, wherein the first cable breakout box further comprises a fourth cable splice and a fourth current transformer;

the fourth cable joint is positioned on the wire inlet side of the first cable distribution box and used for connecting a fourth three-phase branch line which is branched from a third main cable entering from the outside;

the fourth current transformer is located on the incoming line side of the first cable distribution box, and a first end of the fourth current transformer is used for being connected with a fourth three-phase branch line through which the fourth cable joint penetrates, and measuring a current vector of the fourth three-phase branch line; a second end of the fourth current transformer is connected with the first bus, and is used for converging the fourth three-phase branch line on the first bus;

the second three-phase branch line may be formed by merging a first three-phase branch line branched from the first main cable and a fourth three-phase branch line branched from the third main cable.

5. The system of claim 1, wherein the first cable breakout box further comprises a fifth cable splice and a fifth current transformer;

the first end of the fifth current transformer is used for connecting a fifth three-phase branch line which penetrates out after the first three-phase branch line which enters from the outside and is branched from the first main cable is converged by the first bus, and measuring a first current vector of the fifth three-phase branch line;

the fifth cable joint is positioned on the outgoing line side of the first cable tapping box and used for connecting the fifth three-phase branch line penetrating out of the second end of the fifth current transformer; the fifth three-phase branch line is integrated into a fourth main cable at the outlet side of the first cable distribution box; the fourth main cable is an output cable of the first cable distribution box.

6. The system according to claim 1, wherein the second cable breakout box further comprises a second bus bar, a sixth current transformer and a sixth cable joint, the second three-phase branch line branched from the second main cable entering from the outside is converged by the second bus bar, and then the sixth three-phase branch line is led out after passing through the sixth current transformer and the sixth cable joint and is collected into a fifth main cable, and the fifth main cable is used for being led out from the second cable breakout box and then is connected with electric equipment;

the sixth current transformer is located between the second bus and the sixth cable joint, and the sixth current transformer is configured to measure a third current vector of the sixth three-phase branch line between the second bus and the sixth cable joint, and the third current vector is configured to determine a cable status between the sixth current transformer and the electrical equipment.

7. A method of determining a cable condition for use in a processing module of a cable breakout system according to any one of claims 1-6, the system further comprising a first cable breakout box comprising a first bus bar, a first current transformer and a first cable connector, and a second cable breakout box comprising a second current transformer, the method comprising:

obtaining a first current vector from the first current transformer, the first current vector comprising: a first current value and a first current direction flowing through the second three-phase branch line of the first current transformer; the second three-phase branch line penetrates out of the first bus after converging, passes through the first current transformer and the first cable joint and is gathered as a second main cable on the outlet side;

obtaining a second current vector from the second current transformer, the second current vector comprising: a second current value and a second current direction of a third three-phase branch cable branched from a second main cable located in the second cable branching box; the second main cable is an output cable of the first cable distribution box and is connected with the second cable distribution box;

determining a power transfer state between the first current transformer and the second current transformer based on the first current vector and the second current vector.

8. The method of claim 7, wherein determining the state of power transfer between the first current transformer and the second current transformer based on the first current vector and the second current vector comprises:

determining whether the first current direction and the second current direction are the same;

if the first current transformer and the second current transformer are the same, determining that the cable state between the first current transformer and the second current transformer is a fault state;

and if not, determining that the cable state between the first current transformer and the second current transformer is a normal state.

9. The method of claim 7, further comprising, after determining that the power transfer condition between the first current transformer and the second current transformer is a fault condition:

determining an absolute value of a sum of the first current vector and the second current vector to obtain an action current value;

determining an absolute value of a difference between the first current vector and the second current vector to obtain a braking current value;

and if the action current value is larger than the brake current value, starting protection action.

10. An apparatus for determining a cable condition, for use in a processing module of a cable breakout system according to any one of claims 1-6, the system further comprising a first cable breakout box comprising a first bus bar, a first current transformer and a first cable connector, and a second cable breakout box comprising a second current transformer, the apparatus comprising:

a first current vector obtaining module, configured to obtain a first current vector from the first current transformer, where the first current vector includes: a first current value and a first current direction flowing through the second three-phase branch line of the first current transformer; the second three-phase branch line penetrates out of the first bus after converging, passes through the first current transformer and the first cable joint and is gathered as a second main cable on the outlet side;

a second current vector obtaining module, configured to obtain a second current vector from the second current transformer, where the second current vector includes: a second current value and a second current direction of a third three-phase branch cable branched from a second main cable located in the second cable branching box; the second main cable is an output cable of the first cable distribution box and is connected with the second cable distribution box;

a power transfer state determination module configured to determine a power transfer state between the first current transformer and the second current transformer based on the first current vector and the second current vector.

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