CN105548810B - A kind of bus-bar fault gas chamber localization method and device - Google Patents

Abstract

This application discloses a method and device for locating a bus fault air chamber, which is applied in a GIS system. The GIS system includes two bus bars, several air chambers arranged on the bus bars, several switches connected in parallel between the two bus bars, and For the external branch connected by the switch, when the fault location of the bus in the GIS system is carried out, the injection current of each external branch collected by the fault recorder at the fault time and the current distribution of each switch at the fault time are read, and the faults of each branch on the bus are respectively simulated. When the gas chamber fails alone, the current distribution of each switch is calculated by using the injection current of each external branch at the time of the fault, and the current distribution of each switch calculated for the simulated single fault of each gas chamber is compared with the fault recording The current distribution of each switch at the fault time collected by the device is determined as the fault cell by the simulated fault cell with the closest current distribution comparison result. The application narrows down the scope of the micro-water test in the air chamber of the busbar, and improves the fault location efficiency.

Description

A method and device for locating a busbar fault gas chamber

technical field

The present application relates to the technical field of substations, and more specifically, to a method and device for locating a busbar fault gas chamber.

Background technique

In the gas insulated substation GIS (Gas Insulated Substation) system, there are multiple gas chambers on the busbar. Once the gas chambers are damaged, the busbar will fail.

In order to ensure the normal operation of the GIS system, it is necessary to quickly locate the faulty air chamber when the bus fails. In the prior art, when looking for faulty gas chambers, SF6 micro-water tests are generally performed on the busbar gas chambers one by one to detect whether there is a faulty gas in the gas chambers. However, there are often hundreds of air chambers on the bus, and the sizes of the air chambers are not the same. Using the detection method of micro-water testing one by one will greatly prolong the fault location time, and the fault location efficiency is extremely low.

Contents of the invention

In view of this, the present application provides a method and device for locating a faulty air chamber of a busbar, which are used to solve the problems of long fault location time and low efficiency in existing faulty air chamber locating methods.

In order to achieve the above purpose, the proposed scheme is as follows:

A method for locating busbar fault gas chambers, which is applied to the GIS system of SF6 gas insulated substations. The GIS system includes two busbars, several gas chambers arranged on the busbars, several switches connected in parallel between the two busbars and the switches connected The outer branch of , the method includes:

When determining that the busbar of the GIS system fails, read the injection current of each external branch at the fault moment collected by the fault recorder, and the current distribution of each switch at the fault moment collected by the fault recorder, wherein the fault The wave recorder is connected to each external branch respectively;

When simulating the individual faults of each air chamber on the bus, the current distribution of each switch is calculated by using the injection current of each external branch at the time of the fault;

Aiming at the current distribution of each switch calculated for each simulated gas chamber when it fails separately, compare it with the current distribution of each switch at the fault time collected by the fault recorder, and compare the current distribution with the closest simulated fault The air cell is identified as the faulty air cell.

Preferably, the GIS system adopts a three-half connection mode, and when each gas chamber on the simulated bus fails separately, the current distribution of each switch is calculated by using the injection current of each external branch at the time of the fault, including :

Use the node impedance matrix to represent the voltage of each node in the GIS system:

in, Indicates the ground voltage of node i, Represents the external injection current to node i, Z _ii represents the self-impedance of node i, Z _ij represents the impedance between node i and node j;

Define the external branch as k, the injection current of each external branch is I ₁ to I _k , and the node corresponding to the fault gas chamber on the bus is j, then according to Thevenin's theorem, the current of node j is:

Express the current vector in the nodal voltage equation as:

Calculate the node voltage equation to obtain the voltage of each node to ground, and calculate the current distribution of the branch between any two nodes at the fault time:

Among them, when there is a switch between node i and node j, The switch current, Z _ij (lower case) is the impedance of the switch between nodes i and j.

A gas chamber positioning device for busbar faults, which is applied to the GIS system of SF6 gas insulated substations. The GIS system includes two busbars, several gas chambers arranged on the busbars, several switches connected in parallel between the two busbars and the switches connected The external branch circuit, the device includes:

The data reading unit is used to read the injection current of each external branch circuit at the fault time collected by the fault recorder and the current of each switch at the fault time collected by the fault recorder when the bus bar of the GIS system is determined to be faulty. Current distribution, wherein the fault recorder is connected to each external branch circuit respectively;

The current distribution calculation unit is used to calculate the current distribution of each switch by using the injection current of each external branch circuit at the time of the fault when simulating the individual faults of each gas chamber on the bus;

The current distribution comparison unit is used to compare the current distribution of each switch calculated for each simulated individual gas chamber when it fails separately with the current distribution of each switch at the fault time collected by the fault recorder, and compare the current distribution The closest simulated fault cell was identified as the fault cell.

Preferably, the current distribution calculation unit includes:

The first current distribution calculation subunit is used to calculate the voltage of each node in the GIS system when the GIS system adopts the three-half connection mode:

Use the node impedance matrix to represent the voltage of each node in the GIS system:

in, Indicates the ground voltage of node i, Represents the external injection current to node i, Z _ii represents the self-impedance of node i, Z _ij represents the impedance between node i and node j;

Define the external branch as k, the injection current of each external branch is I ₁ to I _k , and the node corresponding to the fault gas chamber on the bus is j, then according to Thevenin's theorem, the current of node j is:

Express the current vector in the nodal voltage equation as:

The second current distribution calculation subunit is used to calculate the current distribution of branches between any two nodes at the fault time after calculating the voltage of each node:

Among them, when there is a switch between node i and node j, is the switch current, Z _ij (lower case) is the impedance of the switch between node i and node j.

It can be seen from the above-mentioned technical solutions that the method for locating the busbar fault air chamber provided by the embodiment of the present application is applied in the GIS system. Several switches and external branches connected to the switches, when the application determines that the busbar of the GIS system fails, it reads the injection current of each external branch at the fault time collected by the fault recorder, and the fault recorder collects The current distribution of each switch at the time of the fault, respectively simulating the individual faults of each gas chamber on the bus, using the injection current of each external branch at the fault time to calculate the current distribution of each switch, and then for the simulated individual faults of each gas chamber The current distribution of each switch calculated at the time is compared with the current distribution of each switch at the fault time collected by the fault recorder, and the simulated fault cell with the closest current distribution comparison result is determined as the fault cell. In this application, when determining the failure of the busbar, the current distribution of each switch when each gas chamber is individually faulted is simulated, and compared with the actual distribution of each switch current collected by the fault recorder, the simulated fault gas with the closest comparison result is The fault chamber is the real fault chamber, so there is no need to locate the fault chamber through the micro-water test method of the bus chamber one by one, which greatly shortens the fault location time and improves the fault location efficiency.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only It is an embodiment of the present application, and those skilled in the art can also obtain other drawings according to the provided drawings without creative work.

Fig. 1 is a common three-half wiring schematic diagram of a 500kV substation example in the present application;

Fig. 2 is a flow chart of a method for locating a bus fault air chamber disclosed in the embodiment of the present application;

Fig. 3 is a schematic structural diagram of a gas chamber positioning device for a bus fault disclosed in an embodiment of the present application;

FIG. 4 is a schematic structural diagram of a current distribution calculation unit disclosed in an embodiment of the present application.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the application with reference to the drawings in the embodiments of the application. Apparently, the described embodiments are only some of the embodiments of the application, not all of them. Based on the embodiments in this application, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the scope of protection of this application.

Referring to FIG. 1 , FIG. 1 is a schematic diagram of a common three-half connection of a 500kV substation as an example of the present application.

As shown in Figure 1, the SF6 gas insulated substation GIS system includes two busbars I busbar and II busbar, several gas chambers Q0-Q6 arranged on the busbars, several switches T011-T033 connected in parallel between the two busbars, external Legs 1-6.

The present application provides a busbar fault air chamber positioning scheme, which is used for quickly locating the faulty air chamber when the busbar air chamber fails. Referring to FIG. 2 , FIG. 2 is a flow chart of a method for locating a bus fault air chamber disclosed in an embodiment of the present application.

As shown in Figure 2, the method includes:

Step S200, when it is determined that the busbar of the GIS system fails, read the injection current of each external branch circuit collected by the fault recorder at the fault time, and the current distribution of each switch at the fault time collected by the fault recorder;

Specifically, the fault recorder is connected to each external branch circuit respectively, and the fault recorder can collect the injection current of each external branch circuit, and at the same time, the fault recorder can also collect the current distribution of each switch.

In this embodiment, the injection current of each external branch circuit at the time of bus failure and the current distribution of each switch at the time of failure can be collected by the fault recorder.

Step S210, when simulating the individual failure of each air chamber on the bus, calculate the current distribution of each switch by using the injection current of each external branch circuit at the time of the failure;

Specifically, according to the circuit principle, in this step, the individual fault time of each gas chamber on the bus is simulated, and the current distribution of each switch is calculated by using the injection current of each external branch circuit at the fault time. For example, assuming that Q0 in FIG. 1 fails, the current distribution of each switch is calculated according to the injection current of branches 1-6.

Step S220, comparing the current distribution of each switch calculated for each simulated individual gas chamber when it fails separately with the current distribution of each switch at the fault time collected by the fault recorder, and comparing the current distribution with the closest result One simulated faulty cell is identified as the faulty cell.

Specifically, the above distribution simulates the switch current distribution when each gas chamber fails individually. In this step, compare the switch current distribution when each gas chamber fails individually with the current distribution of each switch at the fault time collected by the fault recorder. The simulated fault cell with the closest current distribution comparison result is determined as the fault cell.

For example, for the 7 air chambers on the I bus, the result of simulating the switching current distribution when Q0 is faulty is X0, the result of switching current distribution is X1 when Q1 is faulty, the result of switching current distribution is X2 when Q2 is faulty, and the switching current distribution is X2 when Q3 is faulty The distribution result is X3, the switching current distribution result is X4 when Q4 is faulty, the switching current distribution result is X5 when Q5 is faulty, and the switching current distribution result is X6 when Q6 is faulty. The current distribution result of each switch at the time of the fault collected by the fault recorder is Y. After comparison, it is determined that the value of X3 and Y is the closest, and the Q3 air chamber is determined to be the fault air chamber.

The method for locating the busbar fault air chamber provided in the embodiment of the present application is applied in the GIS system. External branches, when the application determines that the busbar of the GIS system fails, read the injection current of each external branch at the fault time collected by the fault recorder, and the current distribution of each switch at the fault time collected by the fault recorder, When each gas chamber on the bus is individually faulted, the current distribution of each switch is calculated by using the injection current of each external branch at the time of the fault, and then the current distribution of each switch calculated for the simulated individual fault of each gas chamber , respectively compare it with the current distribution of each switch at the fault time collected by the fault recorder, and determine the simulated fault cell with the closest current distribution comparison result as the fault cell. In this application, when determining the failure of the busbar, the current distribution of each switch when each gas chamber is individually faulted is simulated, and compared with the actual distribution of each switch current collected by the fault recorder, the simulated fault gas with the closest comparison result is The fault chamber is the real fault chamber, so there is no need to locate the fault chamber through the micro-water test method of the bus chamber one by one, which greatly shortens the fault location time and improves the fault location efficiency.

It should be further explained that, in order to further determine whether the above-mentioned faulty air chamber is actually a faulty air chamber, the SF6 micro-water test can be performed on the above-identified faulty air chamber. Compared with the existing method of performing SF6 micro-water test on all air chambers one by one, this application performs targeted SF6 micro-water test on a single air chamber, greatly improving the fault location efficiency.

What needs to be explained above is that when simulating a gas chamber fault, the specific calculation process of using the external branch circuit injection current to calculate the current distribution of each switch belongs to the prior art. This application does not improve the calculation method, and it can be calculated according to the traditional impedance calculation method. Get the current distribution of each switch.

Next, for the GIS system using the three-half connection method, the calculation process of the switch current distribution is introduced.

Use the node impedance matrix to represent the voltage of each node in the GIS system:

in, Indicates the ground voltage of node i, Represents the external injection current to node i, Z _ii represents the self-impedance of node i, Z _ij represents the mutual impedance between node i and node j;

Define the external branch as k, the injection current of each external branch is I ₁ to I _k , and the node corresponding to the fault gas chamber on the bus is j, then according to Thevenin's theorem, the current of node j is:

Express the current vector in the nodal voltage equation as:

Calculate the node voltage equation to obtain the voltage of each node to ground, and calculate the current distribution of the branch between any two nodes at the fault time:

Among them, when there is a switch between node i and node j, Is the switch current, z _ij is the impedance of the switch between node i and node j.

The current distribution results of each switch can be obtained through the above calculation.

The following describes the bus fault air chamber positioning device provided by the embodiment of the present application. The bus fault gas chamber positioning device described below and the bus fault gas chamber positioning method described above can be referred to in correspondence.

The gas chamber positioning device for busbar faults of the present application is applied in the GIS system of gas-insulated substations. external branch. Referring to FIG. 3 , FIG. 3 is a schematic structural diagram of a gas chamber positioning device for a bus fault disclosed in an embodiment of the present application.

As shown in Figure 3, the device includes:

The data reading unit 31 is used to read the injection current of each external branch at the fault time collected by the fault recorder and each switch at the fault time collected by the fault recorder when it is determined that the bus of the GIS system fails. current distribution, wherein the fault recorder is connected to each external branch respectively;

Specifically, the fault recorder is connected to each external branch circuit respectively, and the fault recorder can collect the injection current of each external branch circuit, and at the same time, the fault recorder can also collect the current distribution of each switch.

In this embodiment, the injection current of each external branch circuit at the time of bus failure and the current distribution of each switch at the time of failure can be collected by the fault recorder.

The current distribution calculation unit 32 is used to calculate the current distribution of each switch by using the injection current of each external branch circuit at the time of the fault when simulating the individual faults of each air chamber on the bus;

Specifically, according to the circuit principle, in this step, the individual fault time of each gas chamber on the bus is simulated, and the current distribution of each switch is calculated by using the injection current of each external branch circuit at the fault time. For example, assuming that Q0 in FIG. 1 fails, the current distribution of each switch is calculated according to the injection current of branches 1-6.

The current distribution comparison unit 33 is used to compare the current distribution of each switch calculated for each simulated air chamber when it fails separately, and compare it with the current distribution of each switch at the fault moment collected by the fault recorder, and compare the current distribution with the current distribution. The closest simulated fault cell to the result is determined as the fault cell.

Specifically, the above distribution simulates the switch current distribution when each gas chamber fails individually. In this step, compare the switch current distribution when each gas chamber fails individually with the current distribution of each switch at the fault time collected by the fault recorder. The simulated fault cell with the closest current distribution comparison result is determined as the fault cell.

The gas chamber positioning device for bus fault provided by the embodiment of the present application is applied in the GIS system. When the present application determines that the bus of the GIS system fails, it reads the injection current of each external branch at the time of the fault collected by the fault recorder, and The current distribution of each switch at the fault time collected by the fault recorder is used to simulate the individual faults of each gas chamber on the bus, and the current distribution of each switch is calculated by using the injection current of each external branch at the fault time, and then for the simulated The current distribution of each switch calculated when each gas chamber fails separately is compared with the current distribution of each switch at the fault time collected by the fault recorder, and the current distribution is compared with the closest simulated fault gas chamber to determine for the fault chamber. In this application, when determining the failure of the busbar, the current distribution of each switch when each gas chamber is individually faulted is simulated, and compared with the actual distribution of each switch current collected by the fault recorder, the simulated fault gas with the closest comparison result is The fault chamber is the real fault chamber, so there is no need to locate the fault chamber through the micro-water test method of the bus chamber one by one, which greatly shortens the fault location time and improves the fault location efficiency.

Optionally, this embodiment of the present application illustrates an optional structure of the above-mentioned current distribution calculation unit 32. As shown in FIG. 4, the current distribution calculation unit 32 may include:

The first current distribution calculation subunit 321 is used to calculate the voltage of each node in the GIS system when the GIS system adopts the three-half connection mode:

Use the node impedance matrix to represent the voltage of each node in the GIS system:

in, Indicates the ground voltage of node i, Represents the external injection current to node i, Z _ii represents the self-impedance of node i, Z _ij represents the mutual impedance between node i and node j;

Define the external branch as k, the injection current of each external branch is I ₁ to I _k , and the node corresponding to the fault gas chamber on the bus is j, then according to Thevenin's theorem, the current of node j is:

Express the current vector in the nodal voltage equation as:

The second current distribution calculation subunit 322 is used to calculate the current distribution of branches between any two nodes at the fault moment after calculating the voltage of each node:

Among them, when there is a switch between node i and node j, Is the switch current, z _ij is the impedance of the switch between node i and node j.

Finally, it should also be noted that in this text, relational terms such as first and second etc. are only used to distinguish one entity or operation from another, and do not necessarily require or imply that these entities or operations, any such actual relationship or order exists. Furthermore, the term "comprises", "comprises" or any other variation thereof is intended to cover a non-exclusive inclusion such that a process, method, article or apparatus comprising a set of elements includes not only those elements, but also includes elements not expressly listed. other elements of or also include elements inherent in such a process, method, article, or device. Without further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article or apparatus comprising said element.

Each embodiment in this specification is described in a progressive manner, each embodiment focuses on the difference from other embodiments, and the same and similar parts of each embodiment can be referred to each other.

The above description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the application. Therefore, the present application will not be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (2)

1. A bus fault gas chamber location method, applied in the SF6 gas insulated substation GIS system, the GIS system includes two bus bars, some gas chambers arranged on the bus bars, several switches connected in parallel between the two bus bars and the An external branch connected by a switch, characterized in that the method comprises: When determining that the busbar of the GIS system fails, read the injection current of each external branch at the fault moment collected by the fault recorder, and the current distribution of each switch at the fault moment collected by the fault recorder, wherein the fault The wave recorder is connected to each external branch respectively; When simulating the individual faults of each air chamber on the bus, the current distribution of each switch is calculated by using the injection current of each external branch at the time of the fault; Aiming at the current distribution of each switch calculated for each simulated gas chamber when it fails separately, compare it with the current distribution of each switch at the fault time collected by the fault recorder, and compare the current distribution with the closest simulated fault The air chamber is determined as a faulty air chamber; The GIS system adopts a three-half connection mode, and when each air chamber on the simulated bus is separately faulted, the current distribution of each switch is calculated by using the injection current of each external branch circuit at the time of the fault, including: Use the node impedance matrix to represent the voltage of each node in the GIS system: in, Indicates the ground voltage of node i, Represents the external injection current to node i, Z _ii represents the self-impedance of node i, Z _ij represents the mutual impedance between node i and node j; Define the external branch as k, the injection current of each external branch is I ₁ to I _k , and the node corresponding to the fault gas chamber on the bus is j, then according to Thevenin's theorem, the current of node j is: Express the current vector in the nodal voltage equation as: Calculate the node voltage equation to obtain the voltage of each node to ground, and calculate the current distribution of the branch between any two nodes at the fault time: Among them, when there is a switch between node i and node j, Is the switch current, z _ij is the impedance of the switch between node i and node j. 2. A gas chamber positioning device for bus failure, applied in the GIS system of SF6 gas insulated substation, the GIS system includes two bus bars, some gas chambers arranged on the bus bars, several switches connected in parallel between the two bus bars and the The external branch of the switch connection, characterized in that the device comprises: The data reading unit is used to read the injection current of each external branch circuit at the fault time collected by the fault recorder and the current of each switch at the fault time collected by the fault recorder when the bus bar of the GIS system is determined to be faulty. Current distribution, wherein the fault recorder is connected to each external branch circuit respectively; The current distribution calculation unit is used to calculate the current distribution of each switch by using the injection current of each external branch circuit at the time of the fault when simulating the individual faults of each gas chamber on the bus; The current distribution comparison unit is used to compare the current distribution of each switch calculated for each simulated individual gas chamber when it fails separately with the current distribution of each switch at the fault time collected by the fault recorder, and compare the current distribution The closest simulated fault cell is determined as the fault cell; The current distribution calculation unit includes: The first current distribution calculation subunit is used to calculate the voltage of each node in the GIS system when the GIS system adopts the three-half connection mode: Use the node impedance matrix to represent the voltage of each node in the GIS system: in, Indicates the ground voltage of node i, Represents the external injection current to node i, Z _ii represents the self-impedance of node i, Z _ij represents the mutual impedance between node i and node j; Define the external branch as k, the injection current of each external branch is I ₁ to I _k , and the node corresponding to the fault gas chamber on the bus is j, then according to Thevenin's theorem, the current of node j is: Express the current vector in the nodal voltage equation as: The second current distribution calculation subunit is used to calculate the current distribution of branches between any two nodes at the fault moment after calculating the voltage of each node: Among them, when there is a switch between node i and node j, Is the switch current, z _ij is the impedance of the switch between node i and node j.