A distribution network maintenance method and system considering non-stop load transfer

Abstract

The present invention relates to the technical field of distribution network maintenance, and proposes a distribution network maintenance method and system that takes into account non-stop load transfer, which includes the following steps: obtaining a topological model of the distribution network, and obtaining operating data of each operable switch in the topological model; based on the operating data of each operable switch and component in the topological model, selecting an operable switch from the operable switches that causes the smallest steady-state current when the switch is closed as a connecting switch; closing the connecting switch, and performing a partial power outage maintenance on the line to be repaired in the distribution network. The present invention selects the operable switch that causes the smallest steady-state current when the switch is closed as the connecting switch, which can ensure that the impact on the safe operation of the power grid during non-stop load transfer is minimized. When the line needs to be repaired, the connecting switch is closed, and then the repaired part is shut down for maintenance, thereby achieving safe and stable non-stop load transfer and maintenance.

Description

Technical Field

[0001] The present invention relates to the technical field of distribution network maintenance, and more particularly to a distribution network maintenance method and system taking into account uninterrupted load transfer. Background Art

[0002] With economic and social development, the demand for power supply reliability is increasing. Traditional distribution networks often require short power outages to maintain equipment, impacting users' electricity experience. At the same time, to ensure the safety and reliability of residential electricity, power grid companies must regularly inspect and maintain the grid. However, to ensure the reliability of residential electricity, power grid companies must minimize power outages. In this context, continuous power outage operations have become a scientific solution to this dilemma.

[0003] my country's power distribution network mainly adopts the closed-loop design and open-loop operation mode. At present, there is a method for load transfer maintenance without power outages. It proposes to select a line suitable for the power supply of the line to be transferred through investigation and detection and conduct an assessment. After the assessment is passed, the cable of the bypass line is connected from the adjacent line to the line connected to the equipment to be repaired. The line connected to the equipment to be repaired and the bypass line switch are tested to be normal. The bypass line switch is closed, and the high-voltage knife switch of the line connected to the maintenance equipment is disconnected. The substation maintenance personnel will shut down the busbar outlet interval to achieve non-stop maintenance. However, this method requires evaluation of each line, which has the problem of low maintenance efficiency. Summary of the Invention

[0004] In order to overcome the defect of low maintenance efficiency of load transfer maintenance without power outage in the above-mentioned prior art, the present invention provides a distribution network maintenance method and system considering load transfer without power outage.

[0005] In order to solve the above technical problems, the technical solutions of the present invention are as follows:

[0006] A method for maintenance of a distribution network considering load transfer without power outages comprises the following steps:

[0007] Obtaining a topological model of the distribution network and obtaining operating data of each operable switch in the topological model;

[0008] selecting, from the operable switches, an operable switch that generates the smallest steady-state switching current when the switch is closed, as a tie switch, based on the operating data of each operable switch and element in the topological model;

[0009] The connecting switch is closed to partially shut down the line to be repaired in the distribution network for maintenance.

[0010] In this technical solution, an operable switch with the smallest steady-state current when the switch is closed is selected as a connecting switch. When the distribution network needs maintenance or a fault occurs, the load of the power supply network that needs maintenance or the fault is transferred to another power supply network through the connecting switch, so that the load can operate without power outage, thereby improving power supply reliability.

[0011] As a preferred solution, the operating data of the operable switches in the topological model include equivalent power supply data of the distribution network, unit impedance and length of each section of the distribution network line, and the load size carried by each section of the distribution network line.

[0012] As a preferred embodiment, the step of selecting a tie switch from the operable switches includes: calculating, based on the operating data of each operable switch and component in the topological model, the switching steady-state current caused by closing each operable switch in the topological model through power flow calculation; selecting the operable switch with the smallest switching steady-state current caused by closing the switch as the tie switch, and using the remaining operable switches as normally closed operating switches.

[0013] As a preferred solution, the step of calculating the opening and closing steady-state current caused by the closing of each operable switch in the topological model through power flow calculation includes: calculating the voltage difference on both sides of each operable switch in the topological model through power flow calculation; calculating the opening and closing steady-state current of the operable switch based on the equivalent impedance of the interconnection circuit in which the operable switch is located and the voltage difference on both sides of the operable switch; and selecting the operable switch with the smallest opening and closing steady-state current as the interconnection switch.

[0014] As a preferred solution, the further steps are as follows: sorting the operable switches from small to large according to their steady-state opening and closing current values, selecting the operable switch with the smallest steady-state opening and closing current when the switch is closed as the tie switch, and using the remaining operable switches as normally closed operating switches; when the tie switch fails, selecting the next operable switch with the next sequence number as the tie switch according to the sorting of the operable switches, and using the remaining operable switches as normally closed operating switches.

[0015] Furthermore, the present invention also proposes a distribution network maintenance system that takes into account uninterrupted load transfer, and applies the distribution network maintenance method that takes into account uninterrupted load transfer proposed in any of the above technical solutions. The distribution network maintenance system includes:

[0016] A data acquisition module, configured to obtain a topological model of the distribution network and operating data of each operable switch in the topological model;

[0017] a calculation module, configured to calculate, based on the operating data of each operable switch and component in the topological model, a switching steady-state current value caused by each operable switch when the switch is closed;

[0018] The maintenance module is used to select an operable switch from the operable switches that causes the smallest opening and closing steady-state current when the switch is closed as a connecting switch based on the opening and closing steady-state current value output by the calculation module, close the connecting switch, and perform a partial power outage maintenance on the line to be maintained in the distribution network.

[0019] As a preferred solution, the operating data collected by the data collection module includes equivalent power supply data of the distribution network, unit impedance and length of each section of the distribution network line, and the load size carried by each section of the distribution network line.

[0020] As a preferred solution, the calculation module includes a power flow calculation unit for calculating the switching steady-state current caused by closing each operable switch in the topology model through power flow calculation.

[0021] Furthermore, the present invention also proposes a device comprising at least one processor and at least one memory connected to the processor, wherein: the memory stores program instructions that can be executed by the processor, and the processor calls the program instructions to execute the distribution network maintenance method considering uninterrupted load transfer proposed in any of the above technical solutions.

[0022] Furthermore, the present invention also proposes a computer-readable storage medium on which a computer program is stored, and the computer program includes program instructions. When the program instructions are executed by a computer, the computer executes the distribution network maintenance method considering uninterrupted load transfer proposed by any of the above technical solutions.

[0023] Compared with existing technologies, the present invention's technical solution offers the following advantages: By selecting as the tie switch an operable switch that minimizes the steady-state current generated when the switch is closed, the present invention ensures that uninterrupted load transfer has minimal impact on the safe operation of the power grid. When line maintenance is required, the tie switch is closed, and the section under maintenance is shut down for maintenance, achieving safe and stable uninterrupted load transfer and maintenance. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a flow chart of a distribution network maintenance method considering load transfer without power outages according to embodiment 1 of the present invention.

[0025] Figure 2 This is a flow chart of a distribution network maintenance method considering load transfer without power outages according to embodiment 2 of the present invention.

[0026] Figure 3 Schematic diagram of the topology model of the distribution network according to embodiment 2 of the present invention.

[0027] Figure 4 This is an architectural diagram of a distribution network maintenance system that takes into account uninterrupted load transfer according to embodiment 3 of the present invention. DETAILED DESCRIPTION

[0028] The accompanying drawings are for illustrative purposes only and are not to be construed as limiting this patent;

[0029] It is understandable to those skilled in the art that some well-known structures and descriptions thereof may be omitted in the drawings.

[0030] The technical solution of the present invention is further described below with reference to the accompanying drawings and embodiments.

[0031] Example 1

[0032] This embodiment proposes a distribution network maintenance method that takes into account load transfer without power outages, such as Figure 1 , which is a flow chart of the distribution network maintenance method considering load transfer without power outages in this embodiment.

[0033] The distribution network maintenance method considering non-stop load transfer proposed in this embodiment includes the following steps:

[0034] S1. Obtain a topology model of a distribution network, and obtain operating data of each operable switch in the topology model.

[0035] S2. Based on the operating data of each operable switch and element in the topology model, select an operable switch from the operable switches that generates the smallest switching steady-state current when the switch is closed as a tie switch.

[0036] S3. Close the tie switch and perform partial power outage maintenance on the line to be repaired in the distribution network.

[0037] In this embodiment, the tie switch is selected as the operable switch that minimizes the steady-state current generated when the switch is closed. This ensures that uninterrupted load transfer has minimal impact on the safe operation of the power grid. When line maintenance is required, the tie switch is closed and the maintenance section is shut down for maintenance, thus achieving safe and stable uninterrupted load transfer and maintenance.

[0038] In an optional embodiment, the operating data of the operable switches in the topology model include equivalent power data of the distribution network, unit impedance and length of each line section of the distribution network, and load size carried by each line section of the distribution network.

[0039] During specific implementation, the distribution network maintenance method proposed in this embodiment is applied to a dual-power supply network.

[0040] As a normally open operating switch, the tie switch mainly plays a connecting role in a dual power supply network. That is, when one of the power supply networks needs maintenance or a fault occurs, the load of the power supply network that needs maintenance or the fault is transferred to the other power supply network by closing the tie switch, so that the load can operate without power outage.

[0041] In dual-power supply networks, operable switches are primarily used to isolate power sources, perform switching operations, and connect and disconnect current circuits. When in the open position, the contacts of an operable switch have insulation distances that meet specified requirements and are clearly marked as disconnected. In the closed position, the switch can carry the current under normal circuit conditions and the current under abnormal conditions (such as a short circuit) within a specified time.

[0042] When the distribution network needs to be inspected and repaired, the dual-power distribution network topology, equipment parameters and operating data are obtained, mainly including the 10kV equivalent power supply of the distribution network, the unit impedance and length of each section of the dual-power distribution network, the load size, and the operable switches of the dual-power distribution network.

[0043] Based on the operating data of each operable switch and component in the topological model, the operable switch with the smallest steady-state current when closed is selected as the tie switch, and the remaining switches are designated as normally closed switches. When maintenance is required at a certain point in the distribution network, the tie switch is closed, and the section under maintenance is shut down for maintenance, thereby achieving safe and stable load transfer and maintenance without power outages.

[0044] Example 2

[0045] This embodiment makes improvements based on the distribution network maintenance method proposed in embodiment 1 that takes into account the load transfer without power outage. Figure 2 , which is a flow chart of the distribution network maintenance method considering load transfer without power outages in this embodiment.

[0046] The distribution network maintenance method considering non-stop load transfer proposed in this embodiment includes the following steps:

[0047] S1. Obtain a topology model of a distribution network, and obtain operating data of each operable switch in the topology model.

[0048] In this embodiment, the operating data of the operable switches in the topology model include equivalent power supply data of the distribution network, unit impedance and length of each line segment of the distribution network, and load size carried by each line segment of the distribution network.

[0049] S2. Based on the operating data of each operable switch and element in the topology model, select an operable switch from the operable switches that generates the smallest switching steady-state current when the switch is closed as a tie switch.

[0050] S3. Close the tie switch and perform partial power outage maintenance on the line to be repaired in the distribution network.

[0051] The step of selecting a tie switch from the operable switches includes: calculating, based on the operating data of each operable switch and component in the topological model, the switching steady-state current caused by closing each operable switch in the topological model through power flow calculation; selecting the operable switch with the smallest switching steady-state current caused by closing the switch as the tie switch, and using the remaining operable switches as normally closed operating switches.

[0052] Furthermore, in this embodiment, the step of calculating the switching steady-state current caused by closing each operable switch in the topology model through power flow calculation includes:

[0053] S2.1. Calculate the voltage difference on both sides of each operable switch in the topology model through power flow calculation.

[0054] S2.2. Calculate the opening and closing steady-state current of the operable switch based on the equivalent impedance of the interconnection circuit in which the operable switch is located and the voltage difference across the operable switch.

[0055] S2.3. Take the operable switch with the smallest steady-state opening and closing current as the tie switch.

[0056] In this embodiment, the switching steady-state current of the operable switch is obtained by dividing the voltage difference between the two sides of the operable switch by the equivalent impedance of the interconnection loop.

[0057] In the specific implementation process, by comparing the voltage differences on both sides of the operable switches one by one, the operable switch with the smallest voltage difference on both sides is selected as the tie switch. When this switch is closed, the loop current caused is the smallest, and the impact on the safe operation of the power grid is minimized.

[0058] In another optional embodiment, the following steps are also included:

[0059] S2.4. Sort the operable switches according to their steady-state opening and closing current values ​​from small to large. Select the operable switch with the smallest steady-state opening and closing current when the switch is closed as the tie switch, and use the remaining operable switches as normally closed operating switches.

[0060] During the specific implementation process, when the interconnecting switch fails, the next operable switch is selected as the interconnecting switch according to the order of the operable switches, and the remaining operable switches are used as normally closed operating switches to ensure the effective execution of uninterrupted load transfer.

[0061] In a specific implementation process, the distribution network maintenance method considering uninterrupted load transfer proposed in this embodiment is applied to Figure 3 The distribution network topology model is shown in Figure 2.

[0062] These include interconnecting switches and operable switches in the distribution power supply network. The interconnected dual-power distribution network usually originates from the same 220kV substation, and then extends to the 110kV substation through a step-down transformer, and then extends to the 10kV substation. The 10kV outgoing lines form an interconnected dual-power distribution network. In order to facilitate the maintenance of the 10kV distribution network, multiple operable switches are usually set to segment the distribution network, such as Figure 3 K1, K2,…Kn in .

[0063] Following the distribution network maintenance method proposed in this embodiment that allows for uninterrupted load transfer, KL is selected as the tie switch between the dual-power distribution networks. When power transfer is required, the tie switch is closed to perform uninterrupted load transfer distribution network maintenance. Upon completion of the distribution network maintenance, the tie switch is opened, and the distribution network returns to a dual-power distribution network structure.

[0064] Example 3

[0065] This embodiment proposes a distribution network maintenance system that takes into account load transfer without power outages, and applies the distribution network maintenance method that takes into account load transfer without power outages proposed in Embodiment 1 or Embodiment 2.

[0066] like Figure 4 , which is an architecture diagram of the distribution network maintenance system considering uninterrupted load transfer in this embodiment.

[0067] The distribution network maintenance system proposed in this embodiment, which takes into account load transfer without power outages, includes a data acquisition module 100 , a calculation module 200 and a maintenance module 300 .

[0068] The data acquisition module 100 in this embodiment is used to obtain a topological model of the power distribution network and to obtain operating data of each operable switch in the topological model.

[0069] In an optional embodiment, the operating data collected by the data collection module 100 includes equivalent power supply data of the distribution network, unit impedance and length of each section of the distribution network line, and the load size carried by each section of the distribution network line.

[0070] The calculation module 200 in this embodiment is used to calculate the switching steady-state current value caused by the closing of each operable switch according to the operating data of each operable switch and component in the topological model.

[0071] In an optional embodiment, the calculation module 200 includes a power flow calculation unit 210 for calculating the switching steady-state current caused by closing each operable switch in the topology model through power flow calculation.

[0072] The maintenance module 300 in this embodiment is used to select an operable switch from the operable switches that causes the smallest opening and closing steady-state current when the switch is closed as a connecting switch based on the opening and closing steady-state current value output by the calculation module 200, close the connecting switch, and perform a partial power outage maintenance on the line to be maintained in the distribution network.

[0073] In a specific implementation process, the distribution network maintenance system considering non-stop load transfer in this embodiment is applied to a dual-power distribution network.

[0074] The distribution network maintenance system uses the data acquisition module 100 to acquire the dual-power distribution network topology, equipment parameters, and operating data, as well as the operating data of all operable switches in the dual-power distribution network. This primarily includes the 10kV equivalent power supply of the distribution network, the unit impedance and length of each section of the dual-power distribution network, and the load carried.

[0075] The data acquisition module 100 transmits the collected data to the calculation module 200. Based on the operating data of each operable switch and component in the topology model, the calculation module 200 calculates the steady-state current caused by the closing of each operable switch. Specifically, the power flow calculation unit 210 in the calculation module 200 calculates the voltage difference across each operable switch in the topology model and calculates the steady-state current of the operable switch based on the equivalent impedance of the interconnection circuit in which the operable switch is located and the voltage difference across the operable switch. The calculation module 200 transmits the calculated steady-state current data for each operable switch to the maintenance module 300.

[0076] Based on the steady-state currents of each operable switch, the maintenance module 300 selects the switch with the lowest steady-state current when closed from all operable switches as the tie switch. When maintenance is required on the distribution network, the tie switch is closed, partially shutting down the line to be repaired.

[0077] Example 4

[0078] This embodiment provides a device including at least one processor and at least one memory connected to the processor.

[0079] The memory stores program instructions that can be executed by the processor, and the processor calls the program instructions to execute the distribution network maintenance method that takes into account uninterrupted load transfer as proposed in Example 1 or Example 2.

[0080] In another embodiment, a computer-readable storage medium is provided, on which a computer program is stored, the computer program including program instructions.

[0081] When the program instructions are executed by a computer, the computer is caused to execute the distribution network maintenance method considering non-stop load transfer as proposed in Example 1 or Example 2.

[0082] The same or similar reference numerals correspond to the same or similar components;

[0083] The terms used in the drawings to describe positional relationships are for illustrative purposes only and should not be construed as limiting this patent;

[0084] Obviously, the above embodiments of the present invention are merely examples for the purpose of clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. Those skilled in the art will appreciate that other variations or modifications can be made based on the above description. It is not necessary and impossible to enumerate all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the claims of the present invention.

Claims

1. A method for maintenance of a distribution network considering load transfer without power outage, characterized in that: The following steps are involved: Obtaining a topological model of the distribution network and obtaining operating data of each operable switch in the topological model; The operating data of the operable switches in the topology model include the equivalent power supply data of the distribution network, the unit impedance and length of each section of the distribution network line, and the load size carried by each section of the distribution network line; selecting, from the operable switches, an operable switch that generates the smallest steady-state switching current when the switch is closed, as a tie switch, based on the operating data of each operable switch and element in the topological model; The step of selecting a tie switch from the operable switches comprises: Based on the operating data of each operable switch and component in the topological model, the switching steady-state current caused by the closing of each operable switch in the topological model is calculated through power flow calculation; the operable switch with the smallest switching steady-state current caused by the closing of the switch is selected as the tie switch, and the remaining operable switches are designated as normally closed operating switches; The connecting switch is closed to partially shut down the line to be repaired in the distribution network for maintenance.

2. The method for maintenance of distribution network considering load transfer without power outage according to claim 1, characterized in that: The steps of calculating the switching steady-state current caused by closing each operable switch in the topology model through power flow calculation include: Calculate the voltage difference on both sides of each operable switch in the topology model through power flow calculation; Calculate the switching steady-state current of the operable switch based on the equivalent impedance of the interconnection circuit where the operable switch is located and the voltage difference on both sides of the operable switch; The operable switch with the smallest steady-state current is selected as the tie switch.

3. The method for power distribution network maintenance considering load transfer without power outage according to claim 1, characterized in that: The following steps are also included: Sort the operable switches according to their steady-state current values ​​from small to large, and select the operable switch with the smallest steady-state current when closed as the tie switch, and use the remaining operable switches as normally closed operation switches; When the tie switch fails, the next operable switch is selected as the tie switch according to the order of the operable switches, and the remaining operable switches are used as normally closed operating switches.

4. A distribution network maintenance system considering load transfer without power outages, applying the distribution network maintenance method considering load transfer without power outages according to any one of claims 1 to 3, characterized in that: include: A data acquisition module, configured to obtain a topological model of the distribution network and operating data of each operable switch in the topological model; a calculation module, configured to calculate, based on the operating data of each operable switch and component in the topological model, a switching steady-state current value caused by each operable switch when the switch is closed; The maintenance module is used to select an operable switch from the operable switches that causes the smallest opening and closing steady-state current when the switch is closed as a connecting switch based on the opening and closing steady-state current value output by the calculation module, close the connecting switch, and perform a partial power outage maintenance on the line to be maintained in the distribution network.

5. The distribution network maintenance system considering load transfer without power outage according to claim 4 is characterized in that: The operating data collected in the data collection module includes the equivalent power supply data of the distribution network, the unit impedance and length of each section of the distribution network line, and the load size carried by each section of the distribution network line.

6. The distribution network maintenance system considering non-stop load transfer according to claim 4 is characterized in that: The calculation module includes a power flow calculation unit, which is used to calculate the switching steady-state current caused by closing each operable switch in the topology model through power flow calculation.

7. An electronic device, characterized in that: It includes at least one processor and at least one memory connected to the processor, wherein: the memory stores program instructions that can be executed by the processor, and the processor calls the program instructions to execute the distribution network maintenance method considering uninterrupted load transfer as described in any one of claims 1 to 3.

8. A computer-readable storage medium, characterized in that A computer program is stored thereon, and the computer program includes program instructions. When the program instructions are executed by a computer, the computer is caused to execute the distribution network maintenance method considering uninterrupted load transfer as described in any one of claims 1 to 3.

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