CN107069676B - Power distribution network fault positioning and rapid isolation recovery control method - Google Patents

Abstract

The present invention provides a distribution network fault location and rapid isolation and recovery control method, including the following steps: according to the different line protection settings of the substation outgoing line, the distributed FA function will be triggered after the protection action; after the fault overcurrent indication is sent and transmitted to each other on the DTU device, the distributed logic locates and processes the overcurrent signal; the distributed logic generates a fault isolation command according to the fault location result, and the DTU drives the corresponding electric operating mechanism to perform the opening operation according to the isolation command, and waits for the opening signal to confirm the successful opening; after the isolation is successful, the distributed logic sends a recovery command to the upstream and downstream of the fault area, and the upstream substation outlet DTU and the downstream contact point DTU drive the corresponding electric operating mechanism to perform the closing operation after receiving the command, and wait for the closing signal to confirm the successful closing. The purpose of the present invention is to provide a distribution network fault location and rapid isolation and recovery control method to effectively realize the positioning and removal of the fault in view of the defects of the prior art.

Description

Distribution Network Fault Location and Rapid Isolation Restoration Control Method

technical field

The invention belongs to the field of electric power, and in particular relates to a distribution network fault location and fast isolation recovery control method.

Background technique

The power system includes four links: generation, transmission, distribution and consumption. Among them, the distribution network, as the last link of power production and supply, directly faces users. The quality and reliability of power supply felt by the majority of residential users are reflected by the distribution network, so its status is very important. As the urban distribution network lines become more and more complex, the demand for new energy access to the distribution network is becoming more and more common, resulting in an increasingly complex distribution network topology, making control operations and accident handling more and more difficult.

Contents of the invention

The purpose of the present invention is to provide a distribution network fault location and fast isolation recovery control method for the defects of the prior art, so as to effectively realize fault location and resection.

The invention provides a distribution network fault location and fast isolation recovery control method, which includes the following steps

In the first step, a distributed intelligent terminal device DTU with intelligent distributed feeder automation FA function of distributed power single ring network is arranged at each ring network node of the distribution network, and each distributed intelligent terminal device DTU automatically adapts to The node position of the overhead line or cable line network where it is located is responsible for collecting the telecontrol information collected by the monitoring unit where it is located.

In the second step, each distributed intelligent terminal device DTU communicates with each other through optical fiber direct connection or EPON mode, and shares the telecontrol information of adjacent distributed intelligent terminal device DTUs to jointly realize the intelligent distributed power single ring network. Feeder automation function.

In the third step, when a short-circuit fault occurs on the line, the intelligent distributed feeder automation DTU of the power single-ring network near the fault point will collect the fault information and transmit it to the adjacent power single-ring network intelligent distributed feeder automation DTU; The single-ring network intelligent distributed feeder automation DTU combines the collected information and the information received from the power single-ring network intelligent distributed feeder automation DTU on the left and right sides of the adjacent power single-ring network intelligent distributed feeder automation DTU for comprehensive analysis. To determine its own status and logical links, and finally complete fault location through timing cooperation.

In the fourth step, each distributed intelligent terminal device DTU starts the fault isolation program according to the result of fault location; first, each distributed intelligent terminal device DTU sends a command to the distributed intelligent terminal device DTU corresponding to the faulty equipment, and the distributed intelligent The terminal device DTU drives the operating mechanism of the corresponding electrical equipment according to the isolation command to perform the opening operation or reclosing operation corresponding to the circuit breaker or load switch in the fault area, and waits for the position signal of the circuit breaker or load switch to confirm the opening, and finally completes the fault isolation .

Step 5: After the isolation is successful, in order to avoid excessive blackout due to accidents, power should be restored to the outlet circuit breaker of the substation and the branch line of the distributed intelligent terminal device DTU in the non-faulty area; , The downstream circuit breaker or load switch sends a recovery command, and the distributed intelligent terminal device DTU at the outlet of the upstream substation and the distributed intelligent terminal device DTU at the downstream contact point drive the electric operating mechanism of the corresponding electrical equipment to perform closing after receiving the command operation, and wait for the confirmation of the closing signal to complete the optimal restoration of the faulty area.

In the above technical solution, the distribution network system is powered by two substation ring networks, and the contact load switch B4 is in the disconnected position. When the point F1 of the line between the two switching stations fails:

Firstly, fault judgment is carried out: circuit breaker G1 in substation A, load switch A1 and load switch B1 in distributed intelligent terminal device DTU1 all detect sudden changes in fault current and fault voltage, distributed intelligent terminal device DTU2 and the distribution behind the line None of the distributed intelligent terminal devices DTU detects a fault, and the fault information is exchanged between adjacent distributed intelligent terminal device DTU cabinets through Ethernet, so that the fault can be located between load switch B1 and load switch A2;

Then perform fault isolation: since the load switches B1 and A2 cannot trip with load, the outlet circuit breaker G1 of the substation is tripped, and the intelligent distributed feeder automation FA of the power single-ring network, the load switch B1 and the load switch A2 are tripped again, and finally Realize fault isolation;

Fault recovery: After the fault isolation is successful, the substation outlet circuit breaker switch G1 is closed, and the load switch A1 in the distributed intelligent terminal device DTU1 in the non-fault area and the branch line resume power supply; the contact load switch B4 is closed, and the distributed intelligent terminal device DTU1 in the non-fault area The intelligent terminal device DTU3 and the load switch B2 in the distributed intelligent terminal device DTU2 and the branch line resume power supply, and the entire fault is handled.

In the above technical solution, the distribution network system is powered by two substation ring networks, in which the contact load switch B4 is in the disconnected position. When the bus F2 point between the switching stations fails:

Firstly, fault judgment is carried out: circuit breaker G1 in substation A, load switch A1 and load switch B1 in distributed intelligent terminal device DTU1, and load switch A2 in distributed intelligent terminal device DTU2 all detect sudden changes in fault current and fault voltage. The load switch B2 in the distributed intelligent terminal device DTU2 and the distributed intelligent terminal device DTU behind the line have not detected any faults, and the adjacent distributed intelligent terminal devices DTU exchange fault information through Ethernet, so it can be judged that the fault occurred in the load switch Between A2 and load switch B2;

Then perform fault isolation: load switches A2 and B2 cannot trip with load, so the outlet circuit breaker G1 of the substation is tripped, and the intelligent distributed feeder automation FA of the power single ring network is tripped, and the load switch A2 and load switch B2 are tripped again to isolate the fault ;

Fault recovery: After the fault isolation is successful, the outlet circuit breaker G1 of the substation is closed, and the distributed intelligent terminal device DTU1 in the non-fault area resumes power supply; the contact load switch B4 is closed, and the distributed intelligent terminal device DTU3 in the non-fault area resumes power supply. The regional distributed intelligent terminal device DTU2 has a power outage to be investigated, and the entire fault has been resolved.

In the above technical solution, the power distribution network system is powered by two substation ring networks, and the contact load switch B4 is in the disconnected position. When the branch line F3 of the switching station fails:

Firstly, fault judgment is carried out: G1 in substation A, load switch A1 and load switch B1 in distributed intelligent terminal device DTU1, load switch A2 and load switch C2 in distributed intelligent terminal device DTU2 all detect faults, distributed intelligent terminal device The load switch B2 in DTU2 and the distributed intelligent terminal device DTU behind the line have not detected any faults, and the adjacent distributed intelligent terminal device DTU cabinets exchange fault information through Ethernet, so it can be judged that the fault occurred downstream of the load switch C2;

Then perform fault isolation: since C2 is a load switch, it cannot trip with load, so the outlet circuit breaker G1 of the substation is tripped, and the intelligent distributed feeder automation FA of the power single ring network is tripped, and C2 is tripped again to isolate the fault;

Fault recovery: After the fault isolation is successful, the substation outlet circuit breaker G1 is closed, the distributed intelligent terminal device DTU1 in the non-fault area, the distributed intelligent terminal device DTU2 and other non-faulty branch lines resume power supply, and the entire fault treatment is completed.

In the above technical solution, after a certain line switch is judged to be faulty, because the load switch cannot cut off the fault current, the circuit breaker at the outlet of the substation is cut off first, and then the fault switch B1 trips again; the downstream adjacent distributed intelligent terminal device DTU and the fault The fault switch A2 adjacent to the switch B1 jumps off to complete the isolation of the fault between the lines.

In the above technical solution, after receiving the trip request from the faulty switch, the terminal FTU1 used to control the circuit breaker at the outlet of the substation will trip the circuit breaker at the outlet of the substation and send a signal to start the intelligent distributed feeder automation function; After successful opening, the isolation success signal is sent, and the outlet circuit breaker of the substation is closed to restore the power supply between the non-faulty area circuit breaker G1 and the load switch A1.

In the above technical solution, the terminal of the tie switch judges that the switch is a tie switch through the power supply path incoming from the terminals on both sides of the adjacent side; when the tie switch receives the fault isolation success signal, it will judge the load transfer; the judgment of the load transfer The basis is: compare the maximum allowable load received by both sides of the tie switch with the normal load before the fault occurs, if the maximum allowable load is greater than the normal load before the fault occurs, the tie switch is closed, otherwise not.

In the above technical solution, after the terminal issues a trip command, if the faulty switch is not disconnected within the specified time, it is considered that the line switch refuses to operate; the distributed feeder automation FA of the overhead line regards the switch failure as a configurable item. If the built-in failure soft clamp of feeder automation FA is set to input, the circuit switch that refuses to operate will send a failure start signal, and the line switch adjacent to the circuit switch that refuses to operate will trip to isolate the fault, and the follow-up recovery logic will proceed normally; if the failure soft clamp is set If it is not put into operation, the circuit switch that refuses to move sends out an intelligent distributed feeder automation function locking signal, the switch of the entire line is locked, and the outlet circuit breaker protection trips.

In the above technical solution, if the line switch does not receive the trip order to open the switch or the close order to switch on, it is a switch malfunction; Type feeder automatic FA locking signal, the switch of the whole line is locked, and the outlet circuit breaker remains closed.

In the above technical solution, the following two methods are used to deal with communication abnormalities between the distributed feeder automation FAs of overhead lines: logic blocking of the whole area or logic blocking of the abnormal area. Send a logic blocking signal to the entire logic operation area to eliminate the possibility of automatic misoperation; the logic blocking of the abnormal area means that after any abnormal communication between terminals is found, only the logic part that uses its channel is blocked. When a fault occurs in the abnormal communication area When , expand the isolation area

In the past, when feeder failures occurred, regardless of the weather and time, the on-duty personnel were required to arrive at the scene in time to find the fault point, report to dispatch in time, and coordinate and cooperate with personnel from different departments to restore power supply. With the help of automation devices, it can be realized The remote operation and automatic operation of fault handling greatly reduce the workload and labor maintenance intensity. The patent conducts in-depth research on the technical realization, engineering application, and engineering testing of distribution network fault location and fast isolation recovery control technology, in order to form a set of standard distribution network fault location and rapid isolation recovery control technology implementation methods, so that This technology can not only run efficiently and stably, but also achieve standardization, so that terminal products produced by different equipment manufacturers can be interconnected and interoperable, and promote the large-scale promotion of this technology. Through the research of this patent, it is of great significance to promote the development of distribution network fault location and rapid isolation recovery control technology to improve the reliability of power supply and meet the high reliability of 99.999% in the core area of power supply A+.

Description of drawings

Fig. 1 is a schematic diagram of distribution network of the present invention

Figure 2 is a schematic diagram of the principle of system networking

Fig. 3 is a schematic diagram of the principle of the present invention

Figure 4 is a schematic diagram of a fault at point F1 on the line between two switching stations

Figure 5 is a schematic diagram of isolation recovery after a fault occurs at point F1 of the line between two switching stations

Figure 6 is a schematic diagram of a fault at point F2 of the bus between switching stations

Figure 7 is a schematic diagram of isolation recovery after a fault occurs at point F2 of the bus between switching stations

Figure 8 is a schematic diagram of a fault at point F3 of the branch line of the switching station

Figure 9 is a schematic diagram of isolation recovery after the fault of point F3 of the branch line of the switching station

Figure 10 is a logic diagram of fault switch action

Figure 11 is the action logic diagram of the outlet circuit breaker

Figure 12 is a logical diagram of the tie switch action

Figure 13 is a typical topology diagram of the primary network frame of the overhead line of the distribution network

Figure 14 is a schematic diagram of the overcurrent signal when the overhead line of a typical open-loop distribution network fails

Figure 15 is a diagram of the isolation process when a typical open-loop power distribution overhead line fails

Figure 16 is a recovery process diagram of a typical open-loop power distribution overhead line failure

Fig. 17 is a schematic diagram of the processing process of the terminal FTU1 after a failure occurs at the position ② shown in the grid structure diagram and the information exchanged with the adjacent terminal.

Figure 18 is a schematic diagram of the action logic process of the terminal RTU1 after a fault occurs at the position ② shown in the grid structure diagram

Figure 19 is the action logic process of terminals FTU2 and FTU5 after a fault occurs at the position ⑤ shown in the network frame structure diagram

Figure 20 is a logic diagram of reclosing analysis

Detailed ways

The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments to facilitate a clear understanding of the present invention, but they do not limit the present invention.

Intelligent distributed feeder automation (FA) communicates with each other through terminals, protection cooperation or timing cooperation. When a fault occurs in the distribution network, it isolates the faulty area, restores the power supply in the non-faulty area, and reports the processing process and results, that is, by collecting the corresponding terminal ( DTU) information, and realize peer-to-peer communication with adjacent terminal equipment, run the control logic of the intelligent distributed FA system, and realize fault location, isolation and power restoration in non-faulty areas.

Each ring network node of the intelligent distributed FA system in the ring network has a DTU (distributed intelligent terminal) with distributed FA function responsible for collecting the information collected by the local monitoring unit. Fault information, and through peer-to-peer communication with other adjacent DTUs to realize the FA function. Generally speaking, the protection and distributed logic devices in the substation are independently configured; the distributed logic devices on the line and the DTU monitoring unit can be combined or configured independently. The distributed logic device in this design is combined with the DTU monitoring unit. The advantage of this mode is that it can exchange information through the internal bus, share resources and hardware, and improve the reliability of communication and algorithms.

The typical configuration is shown in Figure 1. The power supply mode of the primary grid is a hand-in-hand cable line running in an open loop. A and B are the circuit breakers at the outlet of the substation. There are 4 distribution stations in the ring, and the normally open point of the system is the distribution station. 3 "minus 6" switch, DTU intelligent terminal can be configured in each substation and distribution station.

The intelligent distributed FA system adopts the Ethernet structure supporting peer-to-peer communication. The system networking principle is shown in Figure 2, which divides distributed network autonomous areas, and each cable line belongs to an independent distributed autonomous area; each node deploys a two-layer switch, and all switching areas in each autonomous area form a self-healing Optical fiber ring network; a layer-3 switch is deployed in the substation, which is connected to all outgoing layer-2 switches on the lower side, and connected to the SDH backbone network on the upper side.

As shown in Figure 3, the present invention provides a distribution network fault location and fast isolation recovery control method, characterized in that: it includes the following steps:

The first step is to change according to the line protection setting value of the outgoing line of the ring network substation, and the distributed FA function will be triggered after the protection action;

In the second step, after the DTU device sends and transmits the fault overcurrent indication to each other, the distributed logic performs positioning processing on the overcurrent signal, and the comprehensive time is 2 to 3 seconds;

In the third step, the distributed logic generates a fault isolation command according to the fault location result, and the DTU drives the corresponding electric operating mechanism to perform the opening operation according to the isolation command, and waits for the minute signal to confirm the successful opening. The comprehensive time is 1 to 2 seconds + the switching mechanism action time;

Step 4: After the isolation is successful, the distributed logic sends a recovery command to the upstream and downstream of the fault area. After receiving the command, the DTU at the outlet of the upstream substation and the DTU at the downstream contact point drive the corresponding electric operation mechanism to perform the closing operation and wait for the closing operation. The bit signal confirms the closing is successful, and the comprehensive time is 1-2 seconds + the action time of the starting mechanism.

As shown in Figures 4 and 5, when a fault occurs on the line between two switching stations (F1 fault), the specific fault handling process is as follows:

Fault judgment: Faults are detected in G1 in substation A, A1 and B1 in DTU1 cabinets, but no faults are detected in DTU2 cabinets and DTU cabinets behind the line, and fault information is exchanged between adjacent DTU cabinets through optical fiber direct connection or EPON , it can be judged that the fault occurred between B1 and A2.

Fault isolation: Since both B1 and A2 are load switches, they cannot trip with load, so the substation outlet circuit breaker switch G1 is tripped, and FA is started, and B1 and A2 are tripped again to isolate the fault.

Fault recovery: After the fault isolation is successful, switch G1 of the outlet circuit breaker of the substation is closed, and the power supply of A1 and branch lines in DTU1 cabinet in the non-fault area is restored; the contact load switch B4 is closed, and B2 and branch lines in DTU3 cabinets and DTU2 cabinets in the non-fault area are restored Power supply, the entire fault is resolved.

As shown in Figures 6 and 7, when the bus between switching stations fails (F2 fault), the specific fault handling process is as follows:

Fault judgment: G1 in substation A, A1 and B1 in the DTU1 cabinet, and A2 in the DTU2 cabinet all detect faults, but no fault is detected in B2 in the DTU2 cabinet and the DTU cabinet behind the line, and the adjacent DTU cabinets are directly connected by optical fiber Exchanging fault information by means of EPON or EPON, it can be judged that the fault occurred between A2 and B2.

Fault isolation: Since both A2 and B2 are load switches, they cannot trip on load, so the substation outlet circuit breaker switch G1 is tripped, and FA is started, and A2 and B2 are tripped again to isolate the fault.

Fault recovery: After the fault isolation is successful, the outlet circuit breaker switch G1 of the substation is closed, and the power supply of the DTU1 cabinet in the non-faulty area is restored; the contact load switch B4 is closed, and the power supply of the DTU3 cabinet in the non-faulty area is restored, and the entire fault treatment is completed.

As shown in Figures 8 and 9, when the branch line of the switching station fails (F3 fault), the specific fault handling process is as follows:

Fault judgment: G1 in substation A, A1 and B1 in DTU1 cabinet, A2 and C2 in DTU2 cabinet all detect faults, B2 in DTU2 cabinet and the DTU cabinet behind the line do not detect faults, and the adjacent DTU cabinets pass through optical fiber By exchanging fault information in direct connection or EPON mode, it can be judged that the fault occurred downstream of C2.

Fault isolation: Since C2 is a load switch, it cannot trip with load, so the substation outlet circuit breaker switch G1 is tripped, and FA is started, and C2 is tripped again to isolate the fault.

Fault recovery: After the fault isolation is successful, the substation outlet circuit breaker switch G1 is closed, and the non-fault area DTU1 cabinet, DTU2 cabinet and other non-faulty branch lines resume power supply, and the entire fault treatment is completed.

Figure 10 shows the fault switch action logic: the processing process of the terminal DTU2 after the fault occurs and the information exchanged with the adjacent terminal. When the terminal DTU2 determines that B1 is a fault switch, since the load switch cannot cut off the fault current, it is necessary to cut off the circuit breaker at the outlet of the substation first, and then trip the fault switch B1. The terminal DTU3 also has the same processing logic, and the fault switch A2 is tripped to complete the isolation of faults between lines.

As shown in Figure 11, the action logic of the exit circuit breaker: the action logic process of the terminal FTU1. The terminal FTU1 controls the exit circuit breaker of the substation. After receiving the trip request from the faulty switch, it will trip the circuit breaker and send out the FA start signal; When receiving the isolation success signal sent by the faulty switch after it has tripped successfully, close the circuit breaker and restore the power supply of the non-faulty area G1-A1.

As shown in Figure 12, the action logic of the tie switch: the action logic process of the tie switch terminal DTU4, the tie switch B4 can be judged to be a tie switch through the power supply path incoming from the terminals on both sides of the adjacent side. When the contact load switch B4 receives the fault isolation success signal, it will make a load transfer judgment. The basis of judgment in this paper is: compare the maximum allowable load received by both sides of the tie switch with the normal load before the fault occurs, if loadMax>loadFault, then the tie is closed; otherwise, it is not.

Below in conjunction with overhead line network, the present invention is described in further detail:

The typical topology of the primary network frame of the overhead line of the distribution network is shown in Figure 13. The overhead lines are drawn from three 10kV substations, and different lines are interconnected by tie lines to form a line mesh. The line network is divided into a tree structure by three contact points, which meets the characteristics of closed-loop design and open-loop operation.

The substation switch is a circuit breaker, equipped with an intelligent distributed terminal with RTU logic; the switch on the line is a load switch, equipped with an intelligent distributed terminal with FTU logic.

Intelligent distributed distribution network automation equipment communicates with each other, protects and coordinates with time, and when a fault occurs in the distribution network, it isolates the faulty area, restores the power supply in the non-faulty area, and reports the process signal and execution results to the master station, that is, through Collect the information of the corresponding automation equipment, and then exchange information with the adjacent equipment in the form of peer-to-peer communication, and run the intelligent distributed automation control logic on the basis of the above information to realize fault location, isolation and restoration of power supply in non-faulty areas.

The fault-tolerant fault location method of the overhead line network specifically includes the following steps:

1) Fault location

In the fault location process, the location of the fault is judged by the overcurrent signal collected by the automation equipment itself and the overcurrent signal received from the adjacent equipment. For the equipment installed on the outgoing line of the substation or the switch on the pole, after detecting its own over-current signal, it will transmit the over-current signal to the upstream and downstream of the power supply direction at the same time. If a switch only has its own overcurrent signal or only the signal from adjacent equipment, the fault point is located on the external circuit of the switch.

The overcurrent signal of a typical open-loop distribution network overhead line fault is shown in Figure 14. Assuming that the fault occurs on the line at position ①, the protection action of the circuit breaker at the outlet of the substation trips, and only the outlet switch of the substation detects Over-current signal (over-current is indicated by a red dot in the figure), according to the above positioning logic, it can be determined that the fault point is located on the line between substation A and FTU1 switch.

(2) Fault isolation

The fault isolation operation is carried out on the basis of successful fault location. After the fault location is successful, the location logic will generate corresponding fault marks according to different fault points, and the isolation logic will generate corresponding trip signals according to different fault marks. If the fault point is located in the external line, the external fault identification will be generated at the switches at both ends of the line. For external fault flags, the isolation logic will trip the switch where the external fault flag is located.

The isolation process of a typical open-loop power distribution overhead line fault is shown in Figure 15. According to the aforementioned positioning logic, the fault identification will be generated at both ends of the faulty line, that is, the switch at the exit of substation A and the switch of the line to which FTU1 belongs. After the fault isolation logic detects this mark, each automation device sends a corresponding switch trip signal to realize fault isolation.

(3) Power supply restoration

The power supply recovery operation is carried out on the basis of successful fault isolation. When the fault type is an external line fault, the fault recovery process will be triggered, and the recovery command will be sent upstream from the fault area to close the substation exit circuit breaker (if the fault point is between the exit circuit breaker and the first Between a line switch, there is no upstream recovery command), and the recovery command is sent downstream to the tie switch. When the contact point receives the recovery order, it will perform load prediction and load optimization. Load pre-judgment refers to pre-calculating whether the operation of the contact switch will cause the overload operation of the power supply point. If it is overloaded, the operation of the contact switch will not be executed, and a pre-judgment overload signal will be sent out. Load optimization refers to the automatic selection of the power point with the smallest load rate for transfer operation when there are multiple contact switches that can be combined.

The recovery process of a typical open-loop power distribution overhead line fault is shown in Figure 16. After the isolation is successful, since the fault is located on the line outside the substation outlet circuit breaker, no upstream recovery signal is generated and the recovery signal is sent downstream of the fault area. Command to restore the contact point. At this time, there are two contact points, the switch to which FTU2 belongs and the switch to which FTU6 belongs. If both contact points predict overload, the recovery process ends; if one of the contact points predicts overload, the other The contact point executes the closing operation; if neither of the two contact points predicts the overload, the load selection logic selects the power point with the smallest load rate to perform the transfer operation. In the figure, substation B with a smaller load rate is automatically selected for load transfer, and the FTU2 switch performs closing operation.

Figure 17 describes the processing process of the terminal FTU1 after a failure occurs at position ② shown in the grid structure diagram and the information exchanged with the adjacent terminal. When the terminal FTU1 determines that the fault is on the right side of the switch, since the load switch cannot cut off the fault current, it is necessary to cut off the circuit breaker at the outlet of the substation first, and then trip the fault switch.

Figure 18 describes the action logic process of the terminal RTU1 after a fault occurs at position ② shown in the grid structure diagram. The terminal RTU1 controls the circuit breaker at the substation outlet. When receiving a trip request from the faulty switch, it will trip the circuit breaker and send FA start signal; when receiving the isolation success signal sent by the faulty switch after it has successfully tripped, close the circuit breaker and restore the power supply in the non-faulty area.

Figure 19 describes the action logic process of terminals FTU2 and FTU5 after a fault occurs at the position ⑤ shown in the network frame structure diagram. Through the power supply path incoming from the terminals on both adjacent sides, it can be judged that the switches to which FTU2 and FTU5 belong are tie switches. When the tie switch receives the fault isolation success signal, it will make a load transfer judgment. Logical judgments are based on:

Compare the maximum allowable load received by both sides of the tie switch with the normal load before the fault occurs. If loadMax>loadFault, the tie point can be closed, otherwise it cannot be closed. The latter compares the load rate loadBetter of the power supply to which the tie switch belongs on the basis of the former one, and the contact point with a smaller load rate is closed.

Figure 20 depicts the recloser analysis logic. Power system operation experience shows that most of the faults of overhead lines are "instantaneous", and the insulation performance (insulator and air gap) of the line can be restored after the circuit breaker trips, and the reclosing can be successful again, which improves the power system. reliability of power supply. Therefore, automatic reclosing is widely used in overhead line distribution lines. The figure below describes the reclosing analysis process after a fault occurs on the line. When the substation outlet circuit breaker is put into reclosing, the logic will enter the reclosing analysis module. If there is no fault current after reclosing, the reclosing is successful, and the original fault is an instantaneous fault; if there is still a fault current after reclosing, the reclosing fails, the circuit breaker will trip again, the fault is a permanent fault, and the FA will be started later.

The invention effectively improves the reliability of power supply and reduces the probability of failure. Reduce failure recovery time. Through the real-time monitoring of the distribution network and its equipment operation status, the "blind pipe" can be changed to detect and eliminate hidden troubles in time, and reduce the occurrence of failures. It is of great significance to meet the high reliability of 99.999% in the core area of power supply A+. Due to the influence of factors such as uncertain fault points and traffic congestion, the traditional method of relying on manpower to isolate fault points often requires a long time for fault isolation and restoration of power supply, while the power distribution network using FA can achieve this within a few minutes or even a few milliseconds. Completion of fault isolation and normal power supply of non-fault load segments can significantly reduce the scope of fault influence and power outage time, and improve power supply reliability. The invention improves the power quality at the same time. The present invention uses feeder automation to detect feeder equipment in real time, and can monitor the change of power supply voltage and harmonic content of distribution lines in real time, so that operators can find power quality problems in time, and adjust the transformer tap position, input and output by adjusting the operation mode. Measures such as cutting the reactive power compensation capacitor bank. The invention reduces maintenance intensity. In the past, when feeder failures occurred, regardless of the weather and time, the on-duty personnel were required to arrive at the scene in time to find the fault point, report to dispatch in time, and coordinate and cooperate with personnel from different departments to restore power supply. With the help of automation devices, it can be realized The remote operation and automatic operation of fault handling greatly reduce the workload and labor maintenance intensity. The invention forms a set of standard distribution network fault location and rapid isolation recovery control technology implementation methods. This technology can not only run efficiently and stably, but also achieve standardization, so that terminal products produced by different equipment manufacturers can be interconnected and interoperable, and promote the large-scale promotion of this technology.

The content not described in detail in this specification belongs to the prior art known to those skilled in the art.

Claims (9)

1. a kind of distribution network failure positions and quickly isolates recovery control method, it is characterised in that: it includes the following steps

The first step arranges that has the intelligent distributed feeder line of distributed power Single-ring network in each looped network node of power distribution network Distributed intelligent terminal the device DTU, each distributed intelligent terminal device DTU for automating FA function adapt to frame where it automatically Ceases to be busy road or cable run network node location are responsible for collecting the telecontrol information of its location monitoring unit acquisition；

Second step is in communication with each other between each distributed intelligent terminal device DTU by fiber direct connection mode or EPON mode, Share the telecontrol information of adjacent distributions formula intelligent end device DTU mutually, it is common to realize the intelligent distributed feedback of electric power Single-ring network Line automation function；

Third step, the electric power Single-ring network intelligent distribution type feeder automation DTU when short trouble occurs for route, close to fault point It can be collected into fault message, and be transmitted to adjacent electric power Single-ring network intelligent distribution type feeder automation DTU；Each electric power Single-ring network Intelligent distribution type feeder automation DTU combines collected information, and from electric power Single-ring network intelligent distribution type feeder automation The information that adjacent power Single-ring network intelligent distribution type feeder automation DTU is received at left and right sides of DTU carries out comprehensive analysis, comes true Determine oneself state and locating logical link, completes fault location eventually by time cooperation；

4th step, each distributed intelligent terminal device DTU is according to fault location as a result, the program that respective startup separator is isolated； Firstly, each distributed intelligent terminal device DTU sends a command to the corresponding distributed intelligent terminal device DTU of faulty equipment, point Cloth intelligent end device DTU drives the behaviour mechanism of respective electric equipment to the corresponding breaker in fault zone according to isolation order Or on-load switch executes sub-switching operation or reclosing operation is corresponding, and waits breaker or on-load switch position signal to confirm and divide Lock is finally completed Fault Isolation；

5th step after being isolated successfully, in order to avoid forced outage range is excessive, is coped in substation's wire-outgoing breaker, non-faulting The branch line of the distributed intelligent terminal device DTU in region restores electricity；Each distributed intelligent terminal device DTU is to fault zone The breaker or on-load switch of upstream and downstream, which are sent, restores order, the distributed intelligent terminal device DTU of upstream substation exit with And the distributed intelligent terminal device DTU of downstream contact point, after receiving order, the electrically operated institution of driving respective electric equipment is held Row closing operation, and coincidence signal is waited to confirm, the optimization for completing fault zone is restored；

In distribution network system by 2 substation's ring network power supplies, wherein contact on-load switch B4 is open position, when female between switching station When line F2 point breaks down:

Carry out breakdown judge first: on-load switch A1 in the breaker G1 in substation's first, distributed intelligent terminal device DTU1, On-load switch A2 detects the mutation of fault current, false voltage in on-load switch B1, distributed intelligent terminal device DTU2 It measures, the on-load switch B2 and subsequent distributed intelligent terminal device DTU of route does not have in distributed intelligent terminal device DTU2 It detects failure, passes through Ethernet exchanging fault message between adjacent distributed intelligent terminal device DTU, it can be determined that failure hair Life is between on-load switch A2 and on-load switch B2；

Then carry out Fault Isolation: on-load switch A2 and B2 are unable to on-load tripping, therefore are jumped by substation wire-outgoing breaker G1 Open, and electric power Single-ring network intelligent distribution type feeder automation FA, on-load switch A2, on-load switch B2 again tripping with isolated fault；

Carry out fault recovery again: after Fault Isolation success, substation wire-outgoing breaker G1 closes a floodgate, non-faulting area distribution formula intelligence Terminal installation DTU1 restores electricity；It gets in touch with on-load switch B4 to close a floodgate, non-faulting area distribution formula intelligent end device DTU3 restores Power supply, distributed intelligent terminal device DTU2 power failure in fault zone is to be checked, and entire troubleshooting finishes.

2. distribution network failure according to claim 1 positions and quickly isolates recovery control method, it is characterised in that matching Network system is by 2 substation's ring network power supplies, wherein contact on-load switch B4 is open position, the line between Liang Ge switching station When F1 point in road breaks down:

Carry out breakdown judge first: on-load switch A1 in the breaker G1 in substation's first, distributed intelligent terminal device DTU1, On-load switch B1 detects the Sudden Changing Rate of fault current, false voltage, behind distributed intelligent terminal device DTU2 and route Distributed intelligent terminal device DTU do not detect failure, pass through ether between adjacent distributions formula intelligent end device DTU cabinet Net exchange trouble information can be occurred between on-load switch B1 and on-load switch A2 with positioning failure；

Then Fault Isolation is carried out: since on-load switch B1 and A2 are unable to on-load tripping, by substation's wire-outgoing breaker G1 tripping, and electric power Single-ring network intelligent distribution type feeder automation FA, on-load switch B1, on-load switch A2 tripping again, it is final real Existing Fault Isolation；

Carry out fault recovery again: after Fault Isolation success, substation wire-outgoing breaker switch G1 closes a floodgate, non-faulting area distribution formula On-load switch A1 and branch line in intelligent end device DTU1 restore electricity；It gets in touch with on-load switch B4 to close a floodgate, non-faulting region point On-load switch B2 and branch line restore electricity in cloth intelligent end device DTU3, distributed intelligent terminal device DTU2, entire event Barrier is disposed.

3. distribution network failure according to claim 1 positions and quickly isolates recovery control method, it is characterised in that matching Network system is by 2 substation's ring network power supplies, wherein contact on-load switch B4 is open position, when switching station's branch line F3 point occurs When failure:

Carry out breakdown judge first: on-load switch A1, load are opened in the G1 in substation's first, distributed intelligent terminal device DTU1 B1 is closed, on-load switch A2 in distributed intelligent terminal device DTU2, on-load switch C2 detect failure, distributed intelligent terminal The on-load switch B2 and subsequent distributed intelligent terminal device DTU of route does not detect failure in device DTU2, adjacent point Pass through Ethernet exchanging fault message between cloth intelligent end device DTU cabinet, it can be determined that failure occurs at on-load switch C2 Trip；

Then it carries out Fault Isolation: since C2 is on-load switch, being unable to on-load tripping, therefore by substation wire-outgoing breaker G1 Tripping, and electric power Single-ring network intelligent distribution type feeder automation FA, C2 again tripping with isolated fault；

Carry out fault recovery again: after Fault Isolation success, substation wire-outgoing breaker G1 closes a floodgate, non-faulting area distribution formula intelligence The other fault-free branch lines of terminal installation DTU1, distributed intelligent terminal device DTU2 restore electricity, and entire troubleshooting finishes.

4. positioning and quickly isolating recovery control method, feature according to the described in any item distribution network failures of claim 2-3 After Mr. Yu's line switching is judged as failure, due to on-load switch can not disengagement failure electric current, substation exit breaker It is initially switched off, then breakdown switch B1 tripping again；It is adjacent with breakdown switch B1 in the adjacent distributed intelligent terminal device DTU in downstream Breakdown switch A2 tripping, complete isolation between failure line.

5. positioning and quickly isolating recovery control method, feature according to the described in any item distribution network failures of claim 2-3 It, can tripping change after being that the terminal FTU1 for controlling substation exit breaker receives the tripping request from breakdown switch Power station outlet breaker, and issue intelligent distribution type feeder automation function enabling signal；When receive breakdown switch tripping at The isolation pass signal issued after function closes substation exit breaker, restores non-faulting region breaker G1 to on-load switch Power supply between A1.

6. positioning and quickly isolating recovery control method, feature according to the described in any item distribution network failures of claim 2-3 It is that interconnection switch terminal judges that switch is interconnection switch by the supply path that adjacent two lateral terminal is passed to；Work as interconnection switch Fault Isolation pass signal is received, will do it the judgement of load transfer；The judgment basis that load lotus turns to supply is: comparing contact and opens Normality load before closing the maximum permissible load and failure generation that two sides receive, if before maximum permissible load is greater than failure generation Normality load, then interconnection switch closes, otherwise do not conform to.

7. positioning and quickly isolating recovery control method, feature according to the described in any item distribution network failures of claim 2-3 It is terminal after issuing trip signal, breakdown switch is at the appointed time without disjunction, then it is assumed that the line switching is refused It is dynamic；Overhead line distribution feeder automation FA is using malfunctioning switch as configurable item, if overhead line distribution feeder automation FA Built-in failure soft pressing plate is set as putting into, then the line switching of tripping can spread out of unsuccessful reason signal, and the line switching of tripping is adjacent The tripping of side line way switch is normally carried out with isolated fault, subsequent recovery logic；If failure soft pressing plate is set as not putting into, tripping Line switching spread out of intelligent distribution type feeder automation function block signal, the circuit breaker lock of whole route, outlet breaker Trip protection.

8. positioning and quickly isolating recovery control method, feature according to the described in any item distribution network failures of claim 2-3 If being that line switching does not receive jump and enables switch separating brake or do not receive conjunction switch is enabled to close a floodgate is switch malfunction；If judging The line switching of line switching malfunction, then malfunction spreads out of overhead line distribution feeder automation FA block signal, whole route Circuit breaker lock, outlet breaker keep closing a floodgate.

9. positioning and quickly isolating recovery control method, feature according to the described in any item distribution network failures of claim 2-3 Be to occur between overhead line distribution feeder automation FA communication abnormality using following two kinds of processing modes: region-wide logic is closed Lock or abnormal area logic blocking entire area logic blocking refer to after finding that communication abnormality occurs for any terminal room, understand to entire Logic operation region sending logic block signal eliminates a possibility that automation malfunctions；Abnormal area logic blocking refers to It was found that only locking uses the logical gate in its channel after communication abnormality occurs for any terminal room, occur when in communication abnormality region When failure, expand area of isolation.