CN117996692A

CN117996692A - Line fault processing method based on self-adaptive local feeder system

Info

Publication number: CN117996692A
Application number: CN202410106661.6A
Authority: CN
Inventors: 宋智; 国怀玉; 马健程; 胡远婷; 刘进; 刘智洋; 张睿; 郑君; 雷雪婷; 牟泽欣; 张博
Original assignee: State Grid Heilongjiang Electric Power Co Ltd Electric Power Research Institute; State Grid Corp of China SGCC
Current assignee: State Grid Heilongjiang Electric Power Co Ltd Electric Power Research Institute; State Grid Corp of China SGCC
Priority date: 2024-01-25
Filing date: 2024-01-25
Publication date: 2024-05-07

Abstract

A line fault processing method based on a self-adaptive local feeder system relates to an overhead line fault processing method. The utility model aims at overcoming the current self-adaptation type local type feeder automation system central line circuit breaker and need carry out the secondary reclosing for the transformer in the transformer substation can suffer short circuit impact many times in the short time, can appear switch life reduction, the problem that the voltage sag number of times becomes more, include: judging the type of a switch adjacent to a fault point at the side of the transformer substation, and finally adjusting all sectional circuit breakers to be switched on when the switch is a sectional circuit breaker and has instantaneous faults; when permanent faults occur, adjusting a sectional breaker adjacent to a fault point at the side of the transformer substation to be opened; when the transformer station is a branch breaker and has instantaneous faults, finally adjusting the switching-on of the branch breaker adjacent to the fault point at the side of the transformer station; when permanent faults occur, regulating branch breakers adjacent to fault points at the side of the transformer substation to break-off; and when the circuit breaker is divided, adjusting the dividing circuit breaker adjacent to the fault point at the side of the transformer substation to be divided.

Description

Line fault processing method based on self-adaptive local feeder system

Technical Field

The invention relates to a fault processing method for an overhead line.

Background

In-situ feeder automation can accomplish fault isolation through cooperation between terminals without communication functions, and this mode has been applied in many places. Existing in-situ feeder automation systems include voltage-time and voltage-current-time types and adaptive types.

The voltage time feeder automation is only suitable for a simple power distribution network, the configuration of the type must be readjusted after the grid structure is changed, and once a plurality of branches exist on a line and the lines are mutually connected, configuration errors can occur in the process, so that the power outage range is enlarged.

Although the voltage-current time mode can rapidly process transient faults, the outgoing line breaker is required to have the function of three reclosings, so that a user can experience the process of repeated power failure.

The self-adaptive type power distribution system can adapt to a complex power distribution structure, can jointly process ground faults and short-circuit faults, does not need to be reconfigured after the line network frame is adjusted, has adaptability, and still needs to be reclosed for the line breaker. The transformer in the transformer substation can suffer short-circuit impact for many times in a short time, the problems of short service life of a switch and more times of voltage sag can occur, and the processing time of faults is not shortened greatly.

Disclosure of Invention

The invention aims to solve the problems that a traditional line breaker of an adaptive in-situ feeder automation system needs to be reclosed for the second time, so that a transformer in a transformer substation can suffer short-circuit impact for many times in a short time, the service life of a switch is shortened, and the number of voltage sag times is increased, and provides a line fault processing method based on the adaptive in-situ feeder system.

The invention provides a line fault processing method based on a self-adaptive in-situ feeder system, which comprises the following steps:

judging the type of a switch adjacent to a fault point on the side of the transformer substation and the fault type at the fault point, wherein the fault type comprises an instantaneous fault and a permanent fault;

When the type of the switch is a sectional breaker and transient faults are generated at the fault points, finally, all sectional breakers are adjusted to be closed; when the type of the switch is a sectional breaker and a permanent fault is generated at a fault point, finally adjusting the sectional breaker adjacent to the fault point at the side of the transformer substation to be opened;

When the type of the switch is a branch breaker and an instantaneous fault is generated at a fault point, finally adjusting the branch breaker adjacent to the fault point at the side of the transformer substation to be switched on; when the switch type of the transformer substation side adjacent to the fault point is a branch breaker and a permanent fault is generated at the fault point, finally adjusting the branch breaker of the transformer substation side adjacent to the fault point to be opened;

And finally adjusting the demarcation circuit breaker adjacent to the fault point at the side of the transformer substation to be opened when the type of the switch is the demarcation circuit breaker.

Further, when the type of the switch adjacent to the fault point on the substation side is a sectionalizer, the line fault handling method includes the following steps:

Step 21, when a sectional breaker and an outgoing breaker between a fault point and a transformer substation detect short-circuit fault signals, the outgoing breaker starts a second-stage overcurrent protection trip, so that all sectional breakers on a line are disconnected;

Step 22, reclosing after the outlet circuit breaker delays for 2-5 seconds, so that the voltage generated by the transformer substation is transmitted to the sectionalizing circuit breaker through the outlet circuit breaker;

Step 23, switching on the sectionalized breaker capable of continuously detecting the voltage within 5-60 s until the sectionalized breaker adjacent to the fault point at the side of the transformer substation is switched on;

step 24, judging whether a short-circuit fault signal is detected by a sectional circuit breaker adjacent to a fault point at the side of the transformer substation within 40-60 s;

If the fault type is permanent fault, the sectionalized breaker adjacent to the fault point at the side of the transformer substation is disconnected, and fault processing is completed;

otherwise, the fault type is transient fault, and all the sectionalized breakers are switched on to complete fault processing.

Further, when the type of the switch adjacent to the fault point on the substation side is a sectionalizer, the line fault handling method is as follows:

Step 31, when the sectional circuit breakers between the fault point and the transformer substation detect the ground fault signal, tripping after delaying 15-20 s for the sectional circuit breakers adjacent to the transformer substation, so that other sectional circuit breakers on the line are all disconnected;

Step 32, reclosing after delaying the sectionalizing circuit breakers adjacent to the transformer substation for 2-5 s, so that the voltage generated by the transformer substation is transmitted to other sectionalizing circuit breakers through the sectionalizing circuit breakers adjacent to the transformer substation;

step 33, switching on the sectionalized breaker with the voltage continuously detected within 5-60 s until the sectionalized breaker adjacent to the fault point at the side of the transformer substation is switched on;

step 34, judging whether a grounding fault signal is detected by a sectional circuit breaker adjacent to a fault point at the side of the transformer substation within 40-60 s;

Further, the method also comprises the following steps:

When the sectionalized breakers on the line are all opened, the communication breaker starts closing timing, and closes after the closing timing time is reached.

Further, when the switch adjacent to the fault point at the substation side is a branch breaker, the line fault processing method includes the following steps:

step 51, a branch breaker adjacent to a fault point at the side of a transformer substation is disconnected after a fault signal is detected, and an outgoing breaker and a sectionalized breaker through which the fault signal passes are kept switched on;

Step 52, reclosing a branch breaker adjacent to a fault point at the side of the transformer substation;

step 53, judging whether a branch breaker adjacent to a fault point at the transformer substation side detects a fault signal or not;

If the fault type is permanent fault, the branch circuit breaker adjacent to the fault point at the transformer substation side is disconnected, and fault processing is completed;

otherwise, judging the fault type as the instantaneous fault, and finishing fault processing.

Further, the fault signals include a short circuit fault signal and a ground fault signal.

Further, when the switch adjacent to the fault point at the substation side is a demarcation circuit breaker, the line fault processing method comprises the following steps:

Step 71, disconnecting the demarcation circuit breaker adjacent to the fault point at the transformer substation side after detecting the fault signal, and keeping the outgoing circuit breaker and the branch circuit breaker and the sectionalized circuit breaker through which the fault signal passes closed;

step 72, judging whether the current value or the voltage value of the fault signal is less than or equal to the setting value of the branch circuit breaker,

If yes, the outgoing line breaker, the branch breaker and the sectionalized breaker through which the fault signals pass are kept switched on, and fault processing is completed;

Otherwise, the branch circuit breaker trips, and the outgoing circuit breaker and the sectionalized circuit breaker through which the fault signal passes are kept switched on; and then the branch breaker is reclosed to complete fault processing.

The beneficial effects of the invention are as follows:

The line fault processing method based on the self-adaptive in-situ feeder system reduces the impact times of fault current on the switch and the power failure range by means of mutual matching of the circuit breakers at different positions, the fault on the branch only needs to be tripped by the branch, the fault at the user is isolated at the user, and even if the line net rack is changed, all parameters of the circuit breakers do not need to be set again. The method reduces the reclosing times of the outgoing line breaker and solves the step difference problem in multiple protections, thereby having the advantages of reducing the impact of fault current on the line and reducing the power failure time.

Drawings

FIG. 1 is a schematic diagram of a process for handling a short-circuit fault in a circuit in the method of the present invention;

Wherein CB is an outgoing circuit breaker, FS 0-FS 4 are sectional circuit breakers, FZ1 is a branch circuit breaker, YS 0-YS 2 are boundary circuit breakers, LS 1-LS 2 are connecting circuit breakers, and F1-F3 are short circuit fault points;

FIG. 2 is a schematic diagram of the process of the present invention when a ground fault occurs in a line;

wherein CB is an outgoing circuit breaker, FS 0-FS 4 are all sectional circuit breakers, FZ1 is a branch circuit breaker, YS 0-YS 2 are boundary circuit breakers, LS 1-LS 2 are connecting circuit breakers, and F1-F3 are grounding fault points;

FIG. 3 is a simulation model of a line failure in the method of the present invention;

FIG. 4 is a schematic diagram of the logic control principle when the line fails in the method of the present invention;

fig. 5 is a flow chart of the method of the present invention.

Detailed Description

The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

It should be noted that, without conflict, the embodiments of the present invention and features of the embodiments may be combined with each other.

The invention is further described below with reference to the drawings and specific examples, which are not intended to be limiting.

Detailed description of the preferred embodiments

The line fault processing method based on the self-adaptive in-situ feeder system of the embodiment comprises the following steps:

Specifically, the self-adaptive in-situ feeder system of the invention is characterized in that on the premise that all switches of a line are replaced by circuit breakers, different logics are given to the circuit breakers at different positions, so that the circuit breakers meet different requirements, and the switches can be divided into demarcation circuit breakers, branch circuit breakers, sectionalized circuit breakers and outgoing circuit breakers. The different circuit breakers are mutually matched by virtue of processing logic to finish fault positioning and isolation, and meanwhile, the time delay X of switching on the circuit breakers is optimized, so that the processing time of faults is shortened.

In order to ensure coordination and unification, all switching devices use complete equipment with section selecting and line selecting functions, and under the condition of fault occurrence, the self-adaptive on-site feeder system of the invention needs to set corresponding protection configuration and action logic for circuit breakers at different positions:

1. the outgoing circuit breaker in the transformer substation only needs to be provided with the overcurrent protection of the sections II and III, and is provided with one reclosing.

2. The protection configuration of the sectionalizer in the sectionalizer position is set as follows:

1. When the sectional circuit breaker is in a normal closing state, the sectional circuit breaker is locked when a fault overcurrent signal (short-circuit fault signal) is sensed for the first time, and only the fault overcurrent signal is recorded and no action trip is started.

2. Non-pressure brake separating: when the voltage cannot be detected on both the power supply side and the load side of the segment breaker, the segment breaker is opened.

3. Delay closing: when the segment circuit breaker is in the open state and is not locked, closing is delayed after a set X time (first time) when one side of the segment circuit breaker has a voltage.

4. Acceleration of tripping after closing: the sectional breaker under the two conditions that the overcurrent signal is recorded and the fault overcurrent signal is detected again in Y time (second time) after closing is met at the same time is subjected to instantaneous quick breaking (locking is performed at the same time when the two conditions cannot be met, namely the breaker is not broken), and closing in the positive direction is locked after tripping.

5. Automatic locking when incoming call time is too short: when the two sides of the sectionalized breaker have no voltage, one side detects instantaneous residual voltage in a breaking state, and the duration of the voltage is smaller than X time (first time), and the action of reverse closing is locked.

3. The branch breaker at the branch switch position is provided with zero second quick-break protection, one reclosing is required to be configured, and the overcurrent brake-separating function is provided, so that the brake-separating function is not allowed when the voltage is lost.

Under a normal closing state, when a fault overcurrent signal is detected, the action trips: if the circuit breaker is in the transient fault, the circuit breaker is switched on after a short delay, and the circuit is recovered to be normal; if the fault is a permanent fault, the fault is isolated by opening after closing.

4. The demarcation circuit breaker at the demarcation switch position is provided with zero second quick-break protection, reclosing is not required to be configured, overcurrent breaking is also provided, and breaking is not allowed during voltage loss.

5. When no fault occurs on the circuit, the switch is in an off state, if the fault occurs to cause one side to lose voltage, the circuit breaker is switched on after a certain time delay (time for switching on timing), and the delay time is required to be longer than the time for processing the fault at both sides of the switch.

The action logic at the time of occurrence of the fault described herein is summarized and organized as shown in fig. 5.

Detailed description of the preferred embodiments

In the second embodiment, when the type of the switch adjacent to the fault point on the substation side is a sectionalized breaker, the line fault handling method includes the following steps:

Specifically, fig. 1 is a network frame topological diagram of a circuit, switches in the network frame topological diagram all use circuit breakers, an outgoing circuit breaker CB of a transformer substation only needs to keep overcurrent protection of a section II and a section III, the non-time-limit quick-break protection of a section I is removed, protection cooperation is carried out only by a step difference of one stage, and meanwhile, reclosing is only needed once. Corresponding logic is set for different circuit breakers according to different positions of the switch, wherein FS 0-FS 4 are segment circuit breakers, FZ1 is a branch circuit breaker, YS0-YS2 are boundary circuit breakers, and LS1 and LS2 are communication circuit breakers.

The processing process of short-circuit fault on the main line is as follows:

1. When a short-circuit fault occurs at the fault point F1 of the main line as shown in fig. 1, the segment breakers FS0 and FS1 on the fault line detect a fault overcurrent signal (short-circuit fault signal) in a normal operation state, record only the fault overcurrent signal, and do not trip.

2. The outgoing circuit breaker CB is tripped upon detection of an overcurrent signal.

3. The sectionalized circuit breaker on the line is opened due to the loss of voltage, and the closing timing on the communication circuit breaker starts to start. The branch circuit breaker FZ1 and the demarcation circuit breakers YS0-YS2 are not started to trip after being out of voltage.

4. The outgoing circuit breaker CB performs reclosing once, the FS0 senses the voltage, and the circuit breaker CB is closed in a delay way after X time.

5. The voltage is felt on one side of segment breakers FS1 and FS3, and likewise X time delays close.

6. If the fault is an instantaneous fault, normal power supply is recovered after the sectional circuit breaker is switched on, if the fault is a permanent fault, the sectional circuit breaker FS1 is switched on to the fault, the voltage is lost again because the Y time limit is not reached, meanwhile, a fault overcurrent signal is detected before, and the sectional circuit breaker FS1 immediately accelerates tripping and locking to cut the fault.

7. The segment breaker FS3 does not detect a fault overcurrent signal, and remains in the closed state without opening the gate. The segment circuit FS2 senses an instantaneous residual voltage in the open state, and maintains the open state inactive, thereby isolating the fault.

8. The segment breaker FS4 detects a voltage on one side and after a short delay closes, the line resumes a normal power supply state.

Where X is a short delay, typically set at 7s, and Y is a long delay, typically set at 50s.

Detailed description of the preferred embodiments

In the third embodiment, when the type of the switch adjacent to the fault point on the substation side is a sectionalized breaker, the line fault handling method is as follows:

Specifically, the circuit breaker of the first embodiment is also provided with different logic for different positions.

Ground fault handling as shown in fig. 2, description is made of fault logic when the adaptive comprehensive feeder automation of the present invention occurs in a single phase, CB represents an outgoing circuit breaker, FS0 to FS4 represent a sectionalized circuit breaker (FS 0 is set to a line selection mode before terminal installation, the remaining switches are set to a section selection mode), FZ1 represents a branch circuit breaker, and YS0 to YS2 represent demarcation circuit breakers. The sectioning, branching and demarcating circuit breakers are all necessary to be provided with transient direction protection, and the fault is cut off in the nearest area according to the cooperation of time when the fault direction is judged to be positive protection action.

The processing procedure when the main line of the line has the ground fault is as follows:

1. When a fault occurs at the ground fault point F1 of the main line as shown in fig. 2, the segment breakers FS0 and FS1 on the fault line select the ground fault to occur at the rear end thereof by means of a transient algorithm, and record fault signals, but do not trip.

2. The segment breaker FS0 is tripped after a delay.

4. The segment breaker FS0 performs a reclosing, and the voltage is sensed at one side of the segment breakers FS1 and FS3, and the same X time delay is closed.

5. If the fault is an instantaneous fault, normal power supply is recovered after switching on, if the fault is a permanent fault, the sectional circuit breaker FS1 switches on to the fault, zero sequence voltage mutation occurs again because the Y time limit is not reached, meanwhile, a fault signal is detected before, the sectional circuit breaker FS1 immediately accelerates tripping, and the fault is cut off.

6. The segment breaker FS3 does not detect a fault signal, and is kept in a closed state without opening. The segment circuit FS2 senses an instantaneous residual voltage in the open state, and maintains the open state inactive, thereby isolating the fault.

7. The segment breaker FS4 detects a voltage on one side and after a short delay closes, the line resumes a normal power supply state.

The processing logic of the self-adaptive in-situ feeder line system is matched with a transient line selection method when the self-adaptive in-situ feeder line system faces a ground fault, so that the self-adaptive in-situ feeder line system can selectively cut off the fault when the fault occurs, and can process the fault nearby in real time, so that the fault range can not be expanded to the whole line when the fault occurs at the branch, the reduction of the power failure area is realized, the secondary influence on the branch line when the main line breaks down is also realized, and the power failure impact on a user is reduced.

Detailed description of the preferred embodiments

In the fourth embodiment, the second or third embodiment is further described, and the present embodiment further includes the following steps:

Specifically, the switching-on timing time length of the connecting circuit breaker is set to be longer than the longest time of fault isolation, so that the problem that the power failure range is enlarged due to the fact that faults are not isolated when switching occurs is avoided.

Detailed description of the preferred embodiments

In the fifth embodiment, when the switch adjacent to the fault point on the substation side is a branch breaker, the steps of the line fault handling method are as follows:

Detailed description of the preferred embodiments six

In the sixth embodiment, the fifth embodiment is further described, and the fault signal includes a short-circuit fault signal and a ground fault signal.

Specifically, the process of short-circuit fault on the branch line is as follows:

1. When a fault occurs at the fault point F2, if the fault is an instantaneous fault, the power supply is recovered after reclosing of the branch circuit breaker FZ 1.

2. If the fault is permanent, the branch circuit breaker FZ1 senses the fault overcurrent signal and instantaneously operates to cut off the fault, and the segment circuit breakers FS0 and FS1 sense the fault overcurrent signal and record only the fault overcurrent signal.

3. Although the fault overcurrent signal is also detected by the outgoing circuit breaker CB, since the branch circuit breaker FZ1 can be operated instantaneously, the protection of the sections ii and iii of the outgoing circuit breaker CB will not be operated

4. The branch circuit breaker FZ1 is switched on to the fault, and the tripping and locking are accelerated due to the fact that the fault overcurrent signal is detected again in a short time.

The same process flow can be applied to short-circuit faults, and each circuit breaker needs to be configured according to the configuration scheme of the circuit breaker in the third embodiment.

Detailed description of the preferred embodiments

In the seventh embodiment, when a switch adjacent to a fault point on a substation side is a demarcation circuit breaker, the steps of the line fault handling method are as follows:

Detailed description of the preferred embodiments

In the eighth embodiment, the description is further provided of the seventh embodiment, and the fault signal includes a short-circuit fault signal and a ground fault signal.

Specifically, the process of short-circuit fault at the boundary is as follows:

1. When a fault occurs at the fault point F3, the sectional breakers FS0 and FS1 detect a fault overcurrent signal, record the fault overcurrent signal and give an alarm.

2. Both the branch circuit breaker FZ1 and the demarcation circuit breaker YS1 sense the fault overcurrent signal and initiate the quick-break protection, wherein the action current setting value of the demarcation circuit breaker YS1 is larger than that of the branch circuit breaker FZ1. If the detected fault current is smaller than the setting value of the branch circuit breaker FZ1, only the demarcation circuit breaker YS1 trips to cut off the fault, and the branch circuit breaker FZ1 does not act; if the action current is larger than the setting value of the branch circuit breaker FZ1, the branch circuit breaker FZ1 and the demarcation circuit breaker YS1 are both operated, and the branch circuit breaker FZ1 recloses after the fault is removed to restore the power supply in other areas.

In summary, the self-adaptive in-situ feeder system reduces the impact frequency and the power failure range of the switch caused by fault current by virtue of the mutual matching of the circuit breakers at different positions, the faults on the branch only need to be tripped by the branch, the faults at the user are isolated at the user, and under the condition that the network frame of the circuit breaker is changed, the parameters of the circuit breaker do not need to be set again.

The self-adaptive in-situ feeder system and method of the present invention is simulated and analyzed as follows:

taking the existing 10kV overhead line with multiple sections and multiple connection as an example, as shown in fig. 3, the system comprises 2 power supplies, 2 outgoing line breakers and 2 demarcation breakers, 3 section breakers, and 1 branch breaker and connection breaker.

Fault logic control model:

In the simulation process, both short-circuit faults and grounding faults are required, various fault attributes are defined in a model, a fault control model is built, different faults are numbered, logic simulation is facilitated, and the numbers are shown in table 1.

TABLE 1 failure logic numbering

Logic control at the time of failure is shown in fig. 4, where N10 in fig. 4 represents the phase voltage at the power supply location, where the system collects the voltage in real time and converts it into a pulse signal. FLT is a fault triggered module, POW is a delayed fault module, and DIAL1 represents a fault point selection module.

In the simulation, 100 times of short circuits and ground faults are respectively arranged at different positions from the outlet of the transformer substation to the tail end of the line, and different weight values are arranged on experimental data at different positions. Wherein X in the logic processing is set to 7s, the long delay time is set to 50s, and the Y time is set to 5s, and the simulation results are shown in Table 2.

TABLE 2 simulation results

As can be seen from table 2, the existing adaptive type can better handle two types of faults compared with the voltage time type and the voltage current type, and the line fault handling method based on the adaptive in-situ feeder system provided by the invention greatly reduces the handling time when faults occur, further reduces the reclosing times, and reduces the current impact times for the circuit breaker, thereby prolonging the service life.

Although the invention herein has been described with reference to particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present invention. It is therefore to be understood that numerous modifications may be made to the illustrative embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention as defined by the appended claims. It should be understood that the different dependent claims and the features herein may be combined in ways other than as described in the original claims. It is also to be understood that features described in connection with separate embodiments may be used in other embodiments.

Claims

1. The line fault processing method based on the self-adaptive in-situ feeder system is characterized by comprising the following steps:

When the type of the switch is a sectional breaker and transient faults are generated at fault points, finally, all sectional breakers are adjusted to be closed; when the type of the switch is a sectional breaker and a permanent fault is generated at a fault point, finally adjusting the sectional breaker adjacent to the fault point at the side of the transformer substation to be opened;

When the type of the switch is a branch breaker and transient faults are generated at the fault point, finally adjusting the branch breaker adjacent to the fault point at the side of the transformer substation to be closed; when the switch type of the transformer substation side adjacent to the fault point is a branch breaker and a permanent fault is generated at the fault point, finally adjusting the branch breaker of the transformer substation side adjacent to the fault point to be opened;

2. The line fault handling method based on an adaptive in-situ feeder system according to claim 1, wherein when the type of the switch adjacent to the fault point at the substation side is a segment breaker, the line fault handling method comprises the steps of:

step 22, reclosing after the outlet circuit breaker delays for 2-5 s, so that the voltage generated by the transformer substation is transmitted to the sectionalizing circuit breaker through the outlet circuit breaker;

3. The fault handling method based on an adaptive in-situ feeder system as claimed in claim 1, wherein when the type of the switch adjacent to the fault point at the substation side is a segment breaker, the line fault handling method is as follows:

4. A method of fault handling based on an adaptive in situ feeder system as claimed in claim 2 or 3, further comprising the steps of:

5. The fault handling method based on an adaptive in-situ feeder system according to claim 1, wherein when the switch adjacent to the fault point at the substation side is a branch breaker, the line fault handling method comprises the steps of:

6. The adaptive in-situ feeder system based fault handling method of claim 5, wherein the fault signal comprises a short circuit fault signal and a ground fault signal.

7. The fault handling method based on an adaptive in-situ feeder system according to claim 1, wherein when a switch adjacent to a fault point at a substation side is a demarcation circuit breaker, the line fault handling method comprises the steps of:

step 71, disconnecting a demarcation circuit breaker adjacent to a fault point at the side of a transformer substation after detecting a fault signal, and keeping the outgoing circuit breaker and a branch circuit breaker and a sectionalized circuit breaker through which the fault signal passes to be switched on;

8. The adaptive in-situ feeder system based fault handling method of claim 7, wherein the fault signal comprises a short circuit fault signal and a ground fault signal.