Method for connecting busbar differential protection to new extension interval without power failure

Abstract

The invention provides a method for connecting busbar differential protection to a new extension interval without power failure, which comprises the following steps of: detecting the completion condition of preparatory work items before the new extension interval is connected, namely connecting a current loop of the new extension interval by a cable, a virtual loop at a protection device, a virtual loop at an intelligent terminal and a virtual loop at a switch knife switch; all GOOSE loop outlet soft pressing plates are withdrawn, a maintenance pressing plate and a sealing non-working terminal are put into use, and an SCD configuration file is downloaded and stored on a 220kV bus differential protection device; after it is detected that all preparatory work items are completed, a current loop of a new expansion interval is connected to the 220kV bus differential protection device, and function configuration is carried out on all virtual loops according to an SCD configuration file; and carrying out abnormity verification on all loops of the newly-expanded interval, if no abnormity exists, putting 220kV bus differential protection into operation, and further applying for putting the newly-expanded interval into operation. According to the invention, the access risk can be avoided by standardizing the access mechanism of the new extension interval, and the operation safety of the power grid is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of power systems, and in particular to a method for connecting a new expansion interval with a non-stop busbar differential protection. Background Art

[0002] Intelligent technology and big data analysis technology are widely used in substation construction and operation and maintenance, which has obviously improved the maintenance quality of the power system, increased the efficiency of defect analysis and judgment, realized condition-based maintenance, and reduced safety risks.

[0003] At present, smart substations are based on traditional substations and integrate intelligent technology and big data analysis technology to achieve functions such as remote operation, real-time monitoring and autonomous maintenance. With the surge in power grid applications, smart substations often need irregular expansion intervals. However, the existing technology lacks an effective mechanism to regulate the access of new expansion intervals, which makes smart substations often have great risks (such as incorrect sequence, incorrect configuration and data loss) during the access process of new expansion intervals, especially 220kV bus differential protection involves many intervals, which can lead to power grid accidents if not paid attention.

[0004] Therefore, it is necessary to propose a method for connecting the new expansion interval without power outage bus differential protection, so as to avoid the access risk and improve the safety of power grid operation by standardizing the access mechanism of the new expansion interval. Summary of the invention

[0005] The technical problem to be solved by the embodiments of the present invention is to provide a method for accessing a new expansion interval without power outage bus differential protection, which can avoid access risks by standardizing the access mechanism of the new expansion interval and improve the safety of power grid operation.

[0006] In order to solve the above technical problem, an embodiment of the present invention provides a method for accessing a newly expanded interval without power outage bus differential protection, the method comprising the following steps:

[0007] S1. Check the completion of the preparatory work items before the 220kV bus differential protection is connected to the newly expanded interval; wherein, the preparatory work items include the access of the new expanded interval circuit, the exit of the 220kV bus differential protection and the preparation of files; the items of the access of the new expanded interval circuit include the current circuit of the new expanded interval, the virtual circuit at the protection device, the virtual circuit at the intelligent terminal and the virtual circuit at the switch by laying cables; the items of the exit of the 220kV bus differential protection include the exit of the existing GOOSE circuit outlet soft pressure plate in the 220kV bus differential protection, the maintenance pressure plate of the protection device and the intelligent terminal of the newly expanded interval, and the maintenance pressure plate of the 220kV bus differential protection device and the sealing of the non-working terminals of the 220kV bus differential protection device in operation; the items of the file preparation include downloading the SCD configuration files of the virtual circuit at the protection device of the newly expanded interval, the virtual circuit at the intelligent terminal and the virtual circuit at the switch, and storing them on the 220kV bus differential protection device;

[0008] S2. After all preparatory work items have been detected to be completed, the current circuit of the newly expanded interval is connected to the 220kV bus differential protection device, and the virtual circuit at the protection device of the newly expanded interval, the virtual circuit at the intelligent terminal and the virtual circuit at the switch are functionally configured according to the stored SCD configuration file;

[0009] S3. All circuits connected and configured by the 220kV bus differential protection device are verified for abnormalities. When all circuits are verified to be normal, the 220kV bus differential protection is put into operation, and further application is made for the new expansion interval to be put into operation; wherein, the steps of putting into operation the 220kV bus differential protection are specifically as follows: withdrawing the maintenance pressure plate of the protection device and the intelligent terminal of the new expansion interval, withdrawing the maintenance pressure plate of the 220kV bus differential protection device and releasing the sealed non-working terminals of the 220kV bus differential protection device during operation, and putting into operation all GOOSE circuit outlet soft pressure plates in the 220kV bus differential protection.

[0010] Wherein, between step S2 and step S3, the method further comprises the following steps:

[0011] Check whether the current loop access position of the newly expanded interval is consistent with the interval definition in the 220kV bus differential protection device. If not, adjust the access position of the current loop of the newly expanded interval until they are consistent.

[0012] Among them, the virtual circuit at the protection device of the newly expanded interval includes the virtual circuit opened at the starting failure; the virtual circuit at the intelligent terminal of the newly expanded interval includes the virtual circuit opened at the knife switch position; the virtual circuit at the switch knife switch of the newly expanded interval includes the virtual circuit opened at the tripping outlet, the virtual circuit opened at the starting failure, the virtual circuit opened on three sides of the failure linkage tripping, the virtual circuit opened at the locking standby automatic throw-in and the virtual circuit opened at the release of the re-pressure locking.

[0013] Among them, the GOOSE circuit outlet soft pressure plate includes the interval tripping outlet soft pressure plate, the failure-linked three-side outlet soft pressure plate, the locked standby automatic outlet soft pressure plate and the release re-pressure locked outlet soft pressure plate; the non-working terminals of the 220kV bus differential protection device in operation include the interval current circuit terminals and the bus voltage circuit terminals connected to the 220kV bus differential protection device.

[0014] Among them, in step S3, the abnormal verification content in the current loop connected to the 220kV bus differential protection device specifically includes polarity, transformation ratio, accuracy level, insulation inspection and primary and secondary current rise.

[0015] Before executing the step of putting the 220 kV bus differential protection into use, the following steps are also included:

[0016] Perform abnormal verification on the maintenance mechanism of the 220kV bus differential protection device, the protection device of the newly expanded bay and the intelligent terminal;

[0017] Among them, if the maintenance pressure plate of the 220kV bus differential protection device and the maintenance pressure plate of the protection device of the newly expanded interval and the intelligent terminal operate normally when they are put into operation or withdrawn at the same time, no alarm will be given; otherwise, an alarm will be given.

[0018] Before executing the step of putting the 220 kV bus differential protection into use, the following steps are also included:

[0019] Conduct a comprehensive status check on the protection devices of the newly expanded bays, including connection status, operation status, voltage and current sampling, and bay entry status;

[0020] The connection status is determined by checking the connection status of all optical fibers on the back panel of the protection device of the newly expanded interval;

[0021] The operating state is obtained by powering off and restarting and by a self-checking program when it is determined that the connection state of the protection device of the newly expanded interval is normal;

[0022] The voltage and current sampling conditions are determined by checking whether the voltage sampling and current sampling of the protection device of the newly expanded interval are normal, and whether the large difference and small difference current are normal;

[0023] The interval opening condition is determined by checking whether the newly expanded interval opening on the protection device of the newly expanded interval is normal.

[0024] Before executing the step of putting the 220 kV bus differential protection into use, the following steps are also included:

[0025] The 220kV bus differential protection device is subjected to status detection, including fixed value execution status and alarm status; wherein,

[0026] The fixed value execution status is determined by executing the fixed value newly issued after the expansion and checking whether the fixed value and the customized area code are correct;

[0027] The alarm status is determined by checking whether there is an abnormal alarm under load testing of the newly expanded bay.

[0028] Implementing the embodiments of the present invention has the following beneficial effects:

[0029] The present invention standardizes the preparatory work items beforehand, connects the current loop in the newly expanded interval and writes the SCD configuration file of each virtual loop during the process, and then performs abnormal verification on the current loop and all virtual loops in the newly expanded interval. If there is no abnormality in the verification, the system is put into operation, thereby avoiding access risks by standardizing the access mechanism of the newly expanded interval and improving the safety of power grid operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, without paying creative labor, other drawings obtained based on these drawings still belong to the scope of the present invention.

[0031] Figure 1 A flow chart of a method for accessing a new expansion interval without power outage bus differential protection is provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0032] In order to make the objectives, technical solutions and advantages of the present invention more clear, the present invention will be further described in detail below with reference to the accompanying drawings.

[0033] like Figure 1 As shown in the figure, a method for accessing a newly expanded interval without power outage bus differential protection is proposed in an embodiment of the present invention, and the method comprises the following steps:

[0034] Step S1, detecting the completion of the preparatory work items before the 220kV bus differential protection is connected to the newly expanded interval; wherein, the preparatory work items include the access of the new expanded interval circuit, the exit of the 220kV bus differential protection and the preparation of files; the items of the access of the new expanded interval circuit include connecting the current circuit of the new expanded interval, the virtual circuit at the protection device, the virtual circuit at the intelligent terminal and the virtual circuit at the switch by laying cables; the items of the exit of the 220kV bus differential protection include exiting the existing GOOSE circuit outlet soft pressure plate in the 220kV bus differential protection, putting into operation the protection device of the newly expanded interval and the maintenance pressure plate of the intelligent terminal, and putting into operation the maintenance pressure plate of the 220kV bus differential protection device and sealing the non-working terminals of the 220kV bus differential protection device in operation; the items of the file preparation include downloading the SCD configuration files of the virtual circuit at the protection device of the newly expanded interval, the virtual circuit at the intelligent terminal and the virtual circuit at the switch, and storing them in the 220kV bus differential protection device;

[0035] The specific process is as follows: first, prepare for the preparatory work before access, including the access of the newly expanded bay circuit, the withdrawal of the 220kV bus differential protection (i.e. the implementation of safety measures on site) and document preparation.

[0036] At this time, matters concerning the access of the circuit of the newly expanded interval include but are not limited to connecting the current circuit of the newly expanded interval through laying cables, the virtual circuit at the protection device, the virtual circuit at the intelligent terminal and the virtual circuit at the switch. Among them, the virtual circuit at the protection device of the newly expanded interval includes but is not limited to the virtual circuit opened at the start failure; the virtual circuit at the intelligent terminal of the newly expanded interval includes but is not limited to the virtual circuit opened at the switch position; the virtual circuit at the switch of the newly expanded interval includes but is not limited to the virtual circuit opened at the tripping outlet, the virtual circuit opened at the start failure, the virtual circuit opened on the three sides of the failure joint tripping, the virtual circuit opened at the locking standby automatic throw-in, and the virtual circuit opened at the release of the re-pressure locking.

[0037] It should be noted that the work content of the newly expanded interval circuit access also includes connecting the secondary circuits such as the medium-voltage circuit in the newly expanded interval by laying cables.

[0038] At this time, matters concerning the exit of 220kV bus differential protection include but are not limited to exiting the existing GOOSE circuit outlet soft pressure plate in the 220kV bus differential protection, putting into operation the protection device of the newly expanded interval and the maintenance pressure plate of the intelligent terminal, and putting into operation the maintenance pressure plate of the 220kV bus differential protection device and sealing the non-working terminals of the 220kV bus differential protection device in operation. Among them, the GOOSE circuit outlet soft pressure plate includes but is not limited to the interval tripping outlet soft pressure plate, the failure-linked three-side outlet soft pressure plate, the locking standby automatic throw-in outlet soft pressure plate, and the release of the re-pressure locking outlet soft pressure plate; the non-working terminals of the 220kV bus differential protection device in operation include but are not limited to the current circuit terminals of each interval and the bus voltage circuit terminals connected to the 220kV bus differential protection device.

[0039] At this time, the file preparation items include downloading the SCD configuration files of the virtual circuits at the protection device of the newly expanded bay, the virtual circuits at the intelligent terminal, and the virtual circuits at the switch, and storing them on the 220kV bus differential protection device. It should be noted that the downloaded SCD configuration file must correspond to the virtual circuit configured in the items for accessing the newly expanded bay circuit, and before downloading, the original SCD configuration file should be backed up on the 220kV bus differential protection device.

[0040] Secondly, check the completion status of the above-mentioned preparatory work.

[0041] Step S2: After it is detected that all preparatory work items have been completed, the current loop of the newly expanded interval is connected to the 220kV bus differential protection device, and the virtual loop at the protection device of the newly expanded interval, the virtual loop at the intelligent terminal, and the virtual loop at the switch are functionally configured according to the stored SCD configuration file;

[0042] The specific process is that, first, after all preparatory work has been completed, the current loop of the newly expanded interval is connected to the 220kV bus differential protection device.

[0043] It should be noted that before executing step S3, it is necessary to check that the access position should be consistent with the interval definition in the 220kV bus differential protection device. If it is inconsistent, adjust the access position of the current loop of the newly expanded interval until it is consistent. Furthermore, it is necessary to conduct a comprehensive verification and acceptance of the current loop connected to the 220kV bus differential protection device, including polarity, transformation ratio, accuracy level, insulation inspection, and primary and secondary current rise.

[0044] Secondly, check the downloaded SCD configuration files corresponding to all virtual circuits, including the virtual circuits at the protection device of the newly expanded interval, the virtual circuits at the intelligent terminal, and the virtual circuits at the switch, and perform functional configuration according to the downloaded SCD configuration files.

[0045] It should be noted that the functions of the virtual circuits at the protection device, the virtual circuits at the intelligent terminal and the virtual circuits at the switch of the newly expanded interval need to be fully inspected after configuration to ensure that all virtual circuits at the newly expanded interval function correctly. For example, the inspection content includes: the switch position input, start failure input, release of re-pressure lock input and failure tripping three-side functions on the 220kV side, as well as the virtual circuit input function of the protection device start failure input, and the virtual circuit input function of the switch position at the intelligent terminal.

[0046] Step S3, perform abnormal verification on all circuits connected and configured by the 220kV bus differential protection device, and when it is verified that all circuits are normal, put the 220kV bus differential protection into operation, and further apply for the new expansion interval to be put into operation; wherein, the step of putting the 220kV bus differential protection into operation is specifically to withdraw the protection device of the new expansion interval and the maintenance pressure plate of the intelligent terminal, withdraw the maintenance pressure plate of the 220kV bus differential protection device and release the non-working terminals sealed during the operation of the 220kV bus differential protection device, and put all GOOSE circuit outlet soft pressure plates in the 220kV bus differential protection into operation.

[0047] The specific process is that, first, before putting the 220kV bus differential protection into use, in addition to the comprehensive verification and acceptance of the current circuit connected to the 220kV bus differential protection device in step S2, and the comprehensive acceptance of the functions of the virtual circuit at the protection device of the newly expanded interval, the virtual circuit at the intelligent terminal and the virtual circuit at the switch after configuration, it is also necessary to verify the maintenance mechanism of the newly expanded interval.

[0048] Therefore, before executing the step of putting the 220kV bus differential protection into operation, the following steps are also included: abnormal verification is performed on the maintenance mechanism of the 220kV bus differential protection device, the protection device of the newly expanded interval and the intelligent terminal; wherein, if the maintenance pressure plate of the 220kV bus differential protection device and the maintenance pressure plate of the protection device of the newly expanded interval and the intelligent terminal operate normally when they are put into operation or withdrawn at the same time, no alarm is given; otherwise, an alarm is given.

[0049] Furthermore, it is also necessary to check the device status before putting into use the 220kV bus differential protection. Therefore, before executing the step of putting into use the 220kV bus differential protection, the following steps are also included: a comprehensive status detection of the protection device of the newly expanded interval, including the connection status, operation status, voltage and current sampling status, and interval entry status; wherein the connection status is determined by checking the connection status of all optical fibers on the backplane of the protection device of the newly expanded interval; the operation status is obtained by powering off and restarting and by the self-test program when it is determined that the connection status of the protection device of the newly expanded interval is normal; the voltage and current sampling status is determined by checking whether the voltage sampling and current sampling of the protection device of the newly expanded interval are normal, and whether the large difference and small difference current are normal; the interval entry status is determined by checking whether the new expansion interval entry on the protection device of the newly expanded interval is normal.

[0050] It is understandable that it is also necessary to check the status of other interval devices except the newly expanded interval. The content of the inspection is the same as that of the protection device of the newly expanded interval, which will not be repeated here.

[0051] Furthermore, it is also necessary to check the device status before the 220kV bus differential device is put into operation. Therefore, before executing the step of putting the 220kV bus differential protection into operation, the following steps are also included: status detection of the 220kV bus differential protection device, including the fixed value execution status and the alarm status; wherein, the fixed value execution status is obtained by executing the fixed value newly issued after the expansion, and checking whether the fixed value is correct and whether the customized area code is correct; the alarm status is based on the new expansion interval under load testing, and is determined by checking whether there is an abnormal alarm. It can be understood that the device status inspection before the 220kV bus differential device is put into operation should not be limited to the new expansion interval, but can also be extended to the existing interval, which will not be repeated here.

[0052] Secondly, when it is verified that there are no abnormalities in all circuits, the 220kV bus differential protection is activated, that is, on-site safety restoration measures are implemented.

[0053] Among them, the specific steps for putting into use the 220kV bus differential protection are: withdrawing the maintenance pressure plate of the protection device and the intelligent terminal of the newly expanded interval, withdrawing the maintenance pressure plate of the 220kV bus differential protection device and releasing the sealed non-working terminals during the operation of the 220kV bus differential protection device, and putting into use the soft pressure plate of all GOOSE (including existing intervals and newly expanded intervals) circuit outlets in the 220kV bus differential protection.

[0054] Finally, apply for the new expansion interval to be put into operation.

[0055] Implementing the embodiments of the present invention has the following beneficial effects:

[0056] The present invention standardizes the preparatory work items beforehand, connects the current loop in the newly expanded interval and writes the SCD configuration file of each virtual loop during the process, and then performs abnormal verification on the current loop and all virtual loops in the newly expanded interval. If there is no abnormality in the verification, the system is put into operation, thereby avoiding access risks by standardizing the access mechanism of the newly expanded interval and improving the safety of power grid operation.

[0057] A person skilled in the art can understand that all or part of the steps in the above-mentioned embodiment method can be completed by instructing related hardware through a program, and the program can be stored in a computer-readable storage medium, such as ROM / RAM, disk, CD-ROM, etc.

[0058] The above disclosure is only the preferred embodiment of the present invention, which certainly cannot be used to limit the scope of the present invention. Therefore, equivalent changes made according to the claims of the present invention are still within the scope of the present invention.

Claims

1. A method for connecting a new expansion bay to a non-stop bus differential protection, characterized in that: The method comprises the following steps: S1. Check the completion of the preparatory work items before the 220kV bus differential protection is connected to the newly expanded interval; wherein, the preparatory work items include the access of the new expanded interval circuit, the exit of the 220kV bus differential protection and the preparation of files; the items of the access of the new expanded interval circuit include the current circuit of the new expanded interval, the virtual circuit at the protection device, the virtual circuit at the intelligent terminal and the virtual circuit at the switch by laying cables; the items of the exit of the 220kV bus differential protection include the exit of the existing GOOSE circuit outlet soft pressure plate in the 220kV bus differential protection, the maintenance pressure plate of the protection device and the intelligent terminal of the newly expanded interval, and the maintenance pressure plate of the 220kV bus differential protection device and the sealing of the non-working terminals of the 220kV bus differential protection device in operation; the items of the file preparation include downloading the SCD configuration files of the virtual circuit at the protection device of the newly expanded interval, the virtual circuit at the intelligent terminal and the virtual circuit at the switch, and storing them on the 220kV bus differential protection device; S2. After all preparatory work items have been detected to be completed, the current circuit of the newly expanded interval is connected to the 220kV bus differential protection device, and the virtual circuit at the protection device of the newly expanded interval, the virtual circuit at the intelligent terminal and the virtual circuit at the switch are functionally configured according to the stored SCD configuration file; S3. All circuits connected and configured by the 220kV bus differential protection device are verified for abnormalities. When all circuits are verified to be normal, the 220kV bus differential protection is put into operation, and further application is made for the new expansion interval to be put into operation; wherein, the steps of putting into operation the 220kV bus differential protection are specifically as follows: withdrawing the maintenance pressure plate of the protection device and the intelligent terminal of the new expansion interval, withdrawing the maintenance pressure plate of the 220kV bus differential protection device and releasing the sealed non-working terminals of the 220kV bus differential protection device during operation, and putting into operation all GOOSE circuit outlet soft pressure plates in the 220kV bus differential protection.

2. The method for connecting the non-stop bus differential protection to the newly expanded bay as claimed in claim 1, characterized in that: Between step S2 and step S3, the method further comprises the following steps: Check whether the current loop access position of the newly expanded interval is consistent with the interval definition in the 220kV bus differential protection device. If not, adjust the access position of the current loop of the newly expanded interval until they are consistent.

3. The method for connecting the non-stop bus differential protection to the newly expanded bay as claimed in claim 2, characterized in that: The virtual circuit at the protection device of the newly expanded interval includes a virtual circuit opened at the start failure; the virtual circuit at the intelligent terminal of the newly expanded interval includes a virtual circuit opened at the knife switch position; the virtual circuit at the switch knife switch of the newly expanded interval includes a virtual circuit opened at the tripping outlet, a virtual circuit opened at the start failure, a virtual circuit opened on three sides of the failure linkage tripping, a virtual circuit opened at the locking standby automatic throw-in, and a virtual circuit opened at the release of the re-pressure locking.

4. The method for connecting the non-stop bus differential protection to the newly expanded bay as claimed in claim 3, characterized in that: The GOOSE circuit outlet soft pressure plate includes the interval tripping outlet soft pressure plate, the failure-linked three-side outlet soft pressure plate, the locking standby automatic throwing outlet soft pressure plate and the releasing re-pressure locking outlet soft pressure plate; the non-working terminals of the 220kV bus differential protection device in operation include the interval current circuit terminals and the bus voltage circuit terminals connected to the 220kV bus differential protection device.

5. The method for connecting the non-stop bus differential protection to the newly expanded bay as claimed in claim 4, characterized in that: In step S3, the abnormal verification contents in the current loop connected to the 220kV bus differential protection device specifically include polarity, transformation ratio, accuracy level, insulation inspection and primary and secondary current rise.

6. The method for connecting a new expansion bay to a non-stop bus differential protection as claimed in claim 5, characterized in that: Before executing the step of putting the 220 kV bus differential protection into use, the following steps are also included: Perform abnormal verification on the maintenance mechanism of the 220kV bus differential protection device, the protection device of the newly expanded bay and the intelligent terminal; Among them, if the maintenance pressure plate of the 220kV bus differential protection device and the maintenance pressure plate of the protection device of the newly expanded interval and the intelligent terminal operate normally when they are put into operation or withdrawn at the same time, no alarm will be given; otherwise, an alarm will be given.

7. The method for connecting a new expansion bay to a non-stop bus differential protection as claimed in claim 6, characterized in that: Before executing the step of putting the 220 kV bus differential protection into use, the following steps are also included: Conduct a comprehensive status check on the protection devices of the newly expanded bays, including connection status, operation status, voltage and current sampling, and bay entry status; The connection status is determined by checking the connection status of all optical fibers on the back panel of the protection device of the newly expanded interval; The operating state is obtained by powering off and restarting and by a self-checking program when it is determined that the connection state of the protection device of the newly expanded interval is normal; The voltage and current sampling conditions are determined by checking whether the voltage sampling and current sampling of the protection device of the newly expanded interval are normal, and whether the large difference and small difference current are normal; The interval opening condition is determined by checking whether the newly expanded interval opening on the protection device of the newly expanded interval is normal.

8. The method for connecting a new expansion bay to a non-stop bus differential protection as claimed in claim 7, characterized in that: Before executing the step of putting the 220 kV bus differential protection into use, the following steps are also included: The 220kV bus differential protection device is subjected to status detection, including fixed value execution status and alarm status; wherein, The fixed value execution status is determined by executing the fixed value newly issued after the expansion and checking whether the fixed value and the customized area code are correct; The alarm status is determined by checking whether there is an abnormal alarm under load testing of the newly expanded bay.

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