Load transfer method and device, equipment and storage medium

Abstract

The invention provides a load transfer method and device, equipment and a storage medium, and relates to the technical field of high-voltage power distribution networks. The method comprises the following steps: monitoring whether a substation bus loses voltage, wherein a power grid line connected with a substation comprises a new energy power supply; the monitored bus voltage loss is responded, the total load before voltage loss of the power grid line is obtained, and the total load before voltage loss comprises the power grid line load before bus voltage loss and the new energy load borne before the new energy power supply is disconnected from the network; wherein the power grid line is divided into a plurality of line segments, and the load of the power grid line is the sum of line segment loads of the plurality of line segments; searching a total load transfer line which has a connection relationship with the power grid line and can bear the total load before voltage loss according to the total load before voltage loss; and if the total load transfer line is searched, transferring the total load before voltage loss to the total load transfer line. The method is used for ensuring the stable power supply effect of the power grid system containing the distributed new energy.

Description

Technical Field

[0001] The present application relates to the technical field of high-voltage distribution networks, and in particular to a load transfer method, device, equipment and storage medium. Background Art

[0002] With the continuous transformation of energy structure and the pursuit of sustainable development goals, renewable energy technology and new energy electrification technology are experiencing rapid development and updating. With the massive integration of renewable energy into the power system, the emerging energy network model of distributed new energy has become a key area of innovation in the power industry.

[0003] Distributed new energy covers various forms such as solar photovoltaic, wind power, small hydropower and fuel cells, and builds a unique power system based on smart grid technology. By deploying small power generation equipment at the user end, distributed new energy can directly provide electricity to local or regional users, thereby reducing excessive dependence on large power stations and further ensuring the stability of energy supply.

[0004] As distributed renewable energy technologies become more popular, how to ensure the stability of power consumption in power grid systems containing distributed renewable energy has become a common concern. In related technologies, when a substation loses pressure, the load in the power grid system cannot be accurately calculated due to the access of distributed renewable energy, resulting in overload tripping of related lines during load transfer, causing secondary faults in the power grid system. Therefore, how to ensure stable power supply in power grid systems containing distributed renewable energy has become a technical problem that needs to be solved urgently. Summary of the invention

[0005] The embodiments of the present application provide a load transfer method, device, equipment and storage medium to ensure stable power supply of a power grid system containing distributed new energy.

[0006] In a first aspect, an embodiment of the present application provides a load transfer method, including:

[0007] Monitor whether the substation busbar loses voltage. The power grid connected to the substation contains renewable energy sources.

[0008] In response to monitoring of busbar voltage loss, the total load of the power grid line before the voltage loss is obtained, and the total load before the voltage loss includes the power grid line load before the busbar voltage loss and the new energy load carried by the new energy power source before it is disconnected from the grid; wherein, the power grid line is divided into multiple line segments, and the power grid line load is the sum of the line segment loads of the multiple line segments;

[0009] According to the total load before the voltage loss, search for a total load transfer line that is connected to the power grid line and can carry the total load before the voltage loss;

[0010] If a total load transfer line is found, transfer the total load before voltage loss to the total load transfer line.

[0011] In a possible implementation, according to the total load before voltage loss, search for a total load transfer line that has a connection relationship with the power grid line and can carry the total load before voltage loss, including:

[0012] In the distribution network model, according to the total load before voltage loss, search for a total load transfer line that has a connection relationship with the power grid line and can carry the total load before voltage loss. The distribution network model includes power source attributes, power grid line connection relationships, and power grid line load information.

[0013] In a possible implementation, in the distribution network model, according to the total load before voltage loss, search for a total load transfer line that has a connection relationship with the power grid line and can carry the total load before voltage loss, including:

[0014] Based on the distribution network model, obtain the target load of the opposite-side power grid line that has a connection relationship with the power grid line;

[0015] If the sum of the target load and the total load before voltage loss is less than the current limiting value of the opposite-side power grid line, determine the opposite-side power grid line as the total load transfer line.

[0016] In a possible implementation, if no total load transfer line is found, determine the sectional load of the power grid line. The sectional load includes the line load of the rear section of the power grid line that has a connection relationship with the opposite-side power grid line. If the power grid line is connected to a new energy power source, the sectional load also includes the new energy load;

[0017] According to the sectional load and the line connection relationship, search for a sectional load transfer line that can carry the sectional load;

[0018] If a sectional load transfer line is found, transfer the sectional load to the sectional load transfer line.

[0019] In a possible implementation, if the power grid line is connected to a new energy power source, the load transfer method further includes:

[0020] Detect whether the new energy power source has resumed grid connection;

[0021] If it is detected that the new energy power source has resumed grid connection, control the new energy power source to generate electricity at full load and transfer the new energy load to the new energy power source.

[0022] In a possible implementation, it further includes:

[0023] After transferring the new energy load to the new energy power source, obtain the multiple line loads included in the power grid line load;

[0024] Search for a line load transfer line that has a connection relationship with the power grid line and can carry at least one of the multiple line loads according to the multiple line loads.

[0025] If a line load transfer line is found, gradually transfer at least one line load to the line load transfer line according to the connection relationship.

[0026] In a possible implementation, determining the sectional load of the power grid line includes:

[0027] If the power flow direction of the new energy power source is positive, determine the sectional load according to the sum of the new energy load and the line load.

[0028] If the power flow direction of the new energy power source is negative, determine the sectional load according to the difference between the new energy load and the line load.

[0029] In a second aspect, an embodiment of the present application provides a load transfer device, including:

[0030] A monitoring module, configured to monitor whether the substation bus is out of voltage, and the power grid lines connected to the substation include new energy power sources;

[0031] An acquisition module, configured to, in response to monitoring that the bus is out of voltage, acquire the total load before the voltage loss of the power grid line, and the total load before the voltage loss includes the power grid line load and the new energy load carried by the new energy power source;

[0032] A search module, configured to search for a total load transfer line that has a connection relationship with the power grid line and can carry the total load before the voltage loss according to the total load before the voltage loss;

[0033] A transfer module, configured to, if a total load transfer line is found, transfer the total load before the voltage loss to the total load transfer line.

[0034] In a third aspect, an embodiment of the present application provides a load transfer device, including: a memory, a processor;

[0035] The memory stores computer execution instructions;

[0036] The processor executes the computer execution instructions stored in the memory, so that the processor executes the above first aspect and / or various possible implementation manners of the first aspect.

[0037] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium, in which computer execution instructions are stored, and when the computer execution instructions are executed by a processor, they are used to implement the above first aspect and / or various possible implementation manners of the first aspect.

[0038] Fifth aspect, an embodiment of the present application provides a computer program product, including a computer program which, when executed by a processor, implements the above first aspect and / or various possible implementation manners of the first aspect.

[0039] The load transfer method, device, equipment and storage medium provided by the embodiments of the present application, in a scenario where a power grid line connected to a substation includes a new energy power source, when it is detected that the substation bus is de-energized, obtain the load of the power grid line and the new energy load carried by the new energy power source, fully consider the characteristic of the new energy power source tripping off the grid when de-energized, accurately calculate the load before the power grid line trips according to the load of the power grid line and the new energy load, and find a load transfer line that can carry the load before the power grid line trips, avoiding the secondary fault of the power grid caused by the theoretical calculated load value being less than the actual load value due to not considering the characteristics of the new energy power source, and achieving the effect of ensuring stable power supply of the power grid system containing distributed new energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] The accompanying drawings herein are incorporated into the specification and constitute a part of this specification, showing embodiments consistent with the present application and used together with the specification to explain the principles of the present application.

[0041] Figure 1 It is a schematic diagram of a load transfer scenario provided by an embodiment of the present application;

[0042] Figure 2 It is a schematic flow chart of the load transfer method provided by an embodiment of the present application;

[0043] Figure 3 It is a schematic diagram of a distribution network model provided by an embodiment of the present application Figure 1 ;

[0044] Figure 4 It is a schematic diagram of a distribution network model provided by an embodiment of the present application Figure 2 ;

[0045] Figure 5 It is a schematic structural diagram of the load transfer device provided by an embodiment of the present application;

[0046] Figure 6 It is a schematic structural diagram of the load transfer equipment provided by an embodiment of the present application.

[0047] Through the above accompanying drawings, the clear embodiments of the present application have been shown, and there will be more detailed descriptions hereinafter. These accompanying drawings and the textual descriptions are not intended to limit the scope of the concept of the present application in any way, but to explain the concept of the present application to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0048] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The implementations described in the following exemplary embodiments do not represent all implementations consistent with the present application. Instead, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the appended claims.

[0049] With the continuous transformation of the global energy structure and the continuous pursuit of sustainable development goals, renewable energy technology and new energy electrification technology are experiencing rapid development and updating. In the era of large-scale integration of renewable energy into the power system, distributed new energy, an emerging energy network model, has become a key area of innovation in the global power industry. It not only helps promote the clean and low-carbon transformation of energy, but also significantly improves the stability, resilience and operating efficiency of the power grid, thereby promoting the realization of smart grids. Traditional power systems mainly rely on large central power plants. Unlike traditional power systems, power grid systems containing distributed new energy pay more attention to the use of multiple small power generation units, such as homes, commercial facilities and industrial parks. These small-scale new energy power generation equipment are deployed nearby. The relative design of "distribution" and "centralization" breaks the shackles of traditional centralized power generation, shortens the distance of power transmission, reduces the loss during transmission, and also reduces operating costs. These characteristics together constitute the unique advantages of distributed power grids in the energy field. As distributed new energy technologies become popular, how to ensure the stability of power consumption in power grid systems containing distributed new energy has become a common concern.

[0050] Figure 1 Schematic diagram of load transfer scenario provided in the embodiment of the present application. In the renewable energy grid-connected power generation system, since the renewable energy power source has the characteristic of being disconnected from the grid and unable to supply power normally when the line loses voltage, after the renewable energy power source is disconnected from the grid, the load it is responsible for providing also needs to be transferred along with the line load connected to the substation. Figure 1 As shown, when substation 1 loses pressure, the new energy power source connected to the power grid line of substation 1 will be disconnected from the grid. At this time, the load on the power grid line on the pressure-losing side and the load of the new energy power source need to be transferred to the opposite power grid line through the connecting switch, that is, the power grid line connected to substation 2. In the related art, after the substation loses pressure, when calculating the load before the pressure loss, only the load of the power grid line on the pressure-losing side is calculated, and the load provided by the new energy power source before the power grid is disconnected is ignored, resulting in the load actually required to be transferred being greater than the load calculated theoretically. When the load is transferred to the opposite power grid line through the connecting switch, it is easy to exceed the load of the opposite line, thereby causing the opposite line to trip and cause a secondary fault.

[0051] In this regard, the present application provides a load transfer method, the main inventive concept of which includes:

[0052] First, after the substation bus loses voltage, when calculating the load to be transferred, fully consider the load of new energy power sources. The calculated total load before voltage loss includes the grid line load and the new energy load carried by the new energy power sources. Search for the load transfer line in the opposite-side grid line that can carry the total load before voltage loss according to the total load before voltage loss, avoiding the problem that the actual load transfer causes the opposite-side grid line to trip due to exceeding the load of the opposite-side grid line.

[0053] Second, make full use of the characteristic that the new energy power source can automatically resume grid connection after load transfer. When it is impossible to transfer the entire grid line load and the new energy load, first perform segmented load transfer, transfer part of the grid line load and the new energy load. After completing the segmented load transfer, monitor the grid connection situation of the new energy power source. When the new energy power source completes automatic grid connection, control it to generate electricity at full capacity to reduce the load on the load transfer line, and then the entire grid line load of the grid on the voltage-loss side can be transferred to the load transfer line to achieve staged power restoration.

[0054] In summary, the load transfer method provided by the embodiments of the present application can avoid the overload tripping of the opposite-side grid during load transfer, and through segmented load transfer and segmented power restoration, ensure the efficient and reasonable power restoration of the grid line containing the new energy power source after voltage loss.

[0055] The new energy power source provided by the embodiments of the present application can be in various forms such as solar photovoltaic, wind power generation, small hydropower, and fuel cells, and there is no limitation on the specific type of new energy power source.

[0056] The following uses specific embodiments to detail the technical solutions of the present application and how the technical solutions of the present application solve the above technical problems. These several specific embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments. The following will describe the embodiments of the present application in conjunction with the drawings.

[0057] Figure 2 Flow schematic of the load transfer method provided by the present application Figure 1 . The method provided by the embodiments of the present application can be applied to a processor with processing capabilities and grid control functions. As Figure 2 shown, the method includes:

[0058] S201. Monitor whether the substation bus loses voltage. The grid lines connected to the substation include new energy power sources.

[0059] A busbar is a common path in the power grid lines. Many devices are connected to it in a parallel branch form to jointly transmit electrical energy. This path is usually made of copper (copper busbar) or aluminum materials with high electrical conductivity, and has the functions of collecting and distributing electrical energy, and can effectively transmit electrical energy. In a substation, the busbar plays a key role in connecting large electrical equipment such as transformers, instrument transformers, incoming and outgoing lines, and various electrical devices, and is an indispensable part of the power system.

[0060] The main bases for judging busbar voltage loss mainly include the following points: By observing the change of the instrument indication, if the voltage meter shows zero or close to zero, it can be preliminarily judged as busbar voltage loss; The sound equipment in the system will emit an alarm sound to indicate busbar voltage loss; The change of the light signal can also reflect the situation of busbar voltage loss; The relay protection device will act when detecting busbar voltage loss and send out corresponding signals; The automatic device will also perform corresponding actions according to the situation of busbar voltage loss; External signs such as explosion sound, arc light, and wire swing can help confirm busbar voltage loss.

[0061] In some embodiments, a device is set in the power grid line system to monitor the situation of busbar voltage loss. Exemplarily, a voltage monitoring device is set to monitor the busbar voltage value in real time; A relay monitoring device is set to monitor the signals sent by the relay; A video monitoring device is set to monitor the operation of lights, automatic devices in the power grid system, and external signs such as explosion sound, arc light, and wire swing.

[0062] S202. In response to detecting busbar voltage loss, obtain the total load before voltage loss of the power grid line, and the total load before voltage loss includes the power grid line load before busbar voltage loss and the new energy load carried by the new energy power source before it is disconnected from the grid.

[0063] Among them, the power grid line is divided into multiple line segments, and the power grid line load is the sum of the line loads of multiple line segments. Exemplarily, in the grid-connected new energy power generation system as Figure 1 shown, there are multiple power grid lines connected to the 10KV I busbar, such as line A0, line A1, line A2, line A3, line A4, line A5, line A6, line A7, and line A9, etc. Specifically, each line can be divided into multiple line segments by switches. For example, line A3 is divided into two line segments by switches "#1 pole" and "#50 pole".

[0064] In the grid-connected new energy power generation system, the new energy power source is connected to the power grid line, and part or all of the electricity generated by the new energy power source is uploaded to the power grid line. Because inverters all have anti-islanding devices, for safety reasons, new energy power generation will stop when the power grid line loses voltage.

[0065] The anti-islanding protection device is used to prevent the islanding effect. The islanding effect refers to the state where, when the grid line suddenly loses voltage, the grid-connected new energy power generation system still maintains the power supply to the adjacent part of the grid line. Simply put, it means that the grid line is disconnected, but the new energy power generation system is still supplying power, forming an "island". When the grid-connected new energy power generation system is in the island operation state, it may bring serious consequences, such as the voltage and frequency cannot be controlled, which may damage the equipment and even threaten the safety of maintenance personnel.

[0066] S203. Search for the total load transfer line that has a connection relationship with the grid line and can carry the total load before the voltage loss according to the total load before the voltage loss.

[0067] Among them, being able to carry the total load before the voltage loss means that the sum of the load of the load transfer line and the total load before the voltage loss is less than the preset load limit value.

[0068] Exemplarily, use the current value to represent the load of each line and the load limit value. In the Figure 1 shown power grid system, if the load of the grid line on the voltage loss side is 100A, the load of the new energy power source is 140A, the load of the opposite side grid line is 50A, and the load limit value is 400A, then it can be calculated that the total load before the voltage loss to be transferred is 100A + 140A = 240A, and the sum of the total load before the voltage loss and the load of the opposite side line is 240A + 50A = 290A. It is judged that 290A < 400A holds, so this opposite side grid line with a load of 50A can be used as the total load transfer line. In fact, there may be multiple opposite side grid lines that have a connection relationship with the grid line on the voltage loss side, and the total load transfer line that meets the condition of being able to carry the total load before the voltage loss can be searched among multiple opposite side grid lines according to the above discrimination method.

[0069] S204. If the total load transfer line is searched, transfer the total load before the voltage loss to the total load transfer line.

[0070] The load transfer method provided by the embodiment of the present application fully considers the characteristics of the new energy power source, calculates the total load before the voltage loss according to the sum of the grid line before the voltage loss and the load of the new energy power source, and searches for the load transfer line that can carry the total load before the voltage loss in the opposite side grid line according to the total load before the voltage loss, avoiding the problem that the actual load is transferred to exceed the load of the opposite side grid line and causing the opposite side grid line to trip.

[0071] In a possible implementation manner, searching for the total load transfer line that has a connection relationship with the grid line and can carry the total load before the voltage loss according to the total load before the voltage loss includes:

[0072] In the distribution network model, according to the total load before voltage loss, search for the total load transfer line that has a connection relationship with the power grid line and can carry the total load before voltage loss. The distribution network model includes power source attributes, power grid line connection relationships, and power grid line load information.

[0073] Exemplarily, the distribution network model is as Figure 3 shown. This distribution network model includes multiple substations, photovoltaic power stations, power grid line connection switches, and power grid line load information represented by current values. The yellow ones are substations, the ones directly connected to the substations are buses, and the lines connected to the buses are called power grid lines. The solid rectangles in the lines indicate that the switches are in the closed state, and the current values next to the solid rectangles represent the load values introduced by the closing of these switches. The hollow rectangles indicate the open state of the switches. The photovoltaic power stations are represented in the form of "photovoltaic" + "number", for example, "photovoltaic 1" and the "240A" marked below it represent the load size carried by the photovoltaic 1 power station during normal power generation as 240A.

[0074] Exemplarily, when Figure 3 substation #1 of station A on the left in loses voltage, the 10kvI bus connected to it will lose voltage. Further, all the power grid lines A0 - A9 connected to the 10kvI bus will lose voltage and their loads need to be transferred. At this time, the loads can be transferred to the lines connected to substation #1 of station C or the lines connected to substation #1 of station D through switches L0 - L6. At this time, the lines connected to substation #1 of station C or the lines connected to substation #1 of station D can become the opposite - side power grid lines of the voltage - lost power grid lines.

[0075] The load transfer method provided by the embodiments of this application uses a distribution network model that includes power source attributes, power grid line connection relationships, and power grid line load information, intuitively displays the power grid line conditions, and provides a basis for load transfer.

[0076] In a possible implementation manner, in the distribution network model, according to the total load before voltage loss, search for the total load transfer line that has a connection relationship with the power grid line and can carry the total load before voltage loss, including: based on the distribution network model, obtain the target load of the opposite - side power grid line that has a connection relationship with the power grid line; if the sum of the target load and the total load before voltage loss is less than the current - limiting value of the opposite - side power grid line, then determine the opposite - side power grid line as the total load transfer line.

[0077] In an example, Figure 4 for Figure 3Schematic diagram of the partial structure of the shown distribution network model. When line A3 loses voltage, its load of 190 A needs to be transferred. At the same time, for the PV1 power station connected to line A3, its load of 240 A also needs to be transferred. In this distribution network model, it can be seen that there are two opposite-side grid lines with connection relationships: First, through switch L0, the load can be transferred to the opposite-side grid line C5; Second, through switch L1, the load can be transferred to the opposite-side grid line C1. First, obtain the load values of line C5 and line C1. The load value of line C5 is 100 A, and the load value of line C1 is 220 A. Then, calculate the total load before voltage loss as 190 A + 240 A = 430 A. The sum of the load of line C5 and the total load before voltage loss is 100 A + 430 A = 530 A, and the sum of the load of line C1 and the total load before voltage loss is 220 A + 430 A = 650 A. Considering the relationship between the load-carrying capacity of line C5 and line C1 and the current-limiting value of the opposite-side grid line, determine which line can be used as the total load transfer line. If the preset current-limiting value of the opposite-side grid line is greater than 650 A, for example, the preset current-limiting value of the opposite-side grid line is 700 A, then both lines can be used as the total load transfer line, and either line can be arbitrarily selected; if 530 A ≤ the current-limiting value of the opposite-side grid line ≤ 650 A, for example, the preset current-limiting value of the opposite-side grid line is 600 A, then only line C5 can be selected as the total load transfer line. If line C1 is selected, it will cause the grid line connected to line C1 to trip due to exceeding its load-carrying capacity; if the preset current-limiting value of the opposite-side grid line is less than 530 A, then neither line can be selected, otherwise it will cause the opposite-side grid line to trip.

[0078] The load transfer method provided by the embodiment of the present application fully considers the current-limiting value of the opposite-side grid line, searches for the total load transfer line that can carry the total load before voltage loss in the distribution network model, and avoids the overload tripping of the opposite-side grid line due to exceeding the load-carrying capacity of the opposite-side grid line.

[0079] In a possible implementation manner, if the total load transfer line cannot be searched, determine the sectional load of the grid line. The sectional load includes the line load of the rear section of the grid line close to the opposite-side grid line. If the grid line is connected to a new energy power source, the sectional load also includes the new energy load;

[0080] According to the sectional load and the line connection relationship, search for the sectional load transfer line that can carry the sectional load;

[0081] If the sectional load transfer line is searched, transfer the sectional load to the sectional load transfer line.

[0082] It can be understood that if the power grid line is not connected to a new energy power source, the sectional load is less than the load of the entire line. It is relatively easy to search in the opposite power grid line to transfer the load on the power grid line in the power grid line sectionally, so as to realize the restoration of the local power supply of the de-energized side power grid as much as possible.

[0083] If the power grid line is connected to a new energy power source, according to the characteristics of the new energy power source, after the load of the new energy power source is transferred, the new energy power source can automatically resume grid connection and restart power generation. Therefore, the idea of the embodiment of this application is to preferentially transfer the new energy load, so as to restore the grid-connected power generation of the new energy power source and reduce the load transfer burden on the opposite power grid line.

[0084] The load transfer method provided by the embodiment of this application, when the opposite power grid line cannot bear all the loads of the de-energized side power grid line and the new energy power source, uses the method of sectional transfer power supply. First, transfer a part of the power grid line load and the load of the new energy power source to create conditions for the new energy power source to resume grid connection, reduce the load transfer burden on the opposite power grid line, and ensure the power supply of the de-energized side power grid line as much as possible.

[0085] In a possible implementation manner, if the power grid line is connected to a new energy power source, the load transfer method further includes:

[0086] Detect whether the new energy power source has resumed grid connection;

[0087] If it is detected that the new energy has resumed grid connection, control the new energy power source to generate electricity at full capacity and transfer the new energy load to the new energy power source.

[0088] After the load of the new energy power source is transferred, the new energy power source can automatically resume grid connection. Detect the grid connection status of the new energy power source. If it is detected that the new energy power source has resumed grid connection, it means that the load of the new energy power source no longer needs to be borne by the opposite power grid line. Control the new energy power source to generate electricity at full load and transfer the new energy load to the new energy power source, which can reduce the load pressure on the opposite power grid line.

[0089] The load transfer method provided by the embodiment of this application utilizes the characteristic that the new energy power source can automatically connect to the grid after the load is transferred, continuously detects the grid connection status of the new energy power source, and fully utilizes the new energy power source immediately after detecting that the new energy power source has resumed grid connection, reducing the load pressure on the opposite power grid line.

[0090] In a possible implementation manner, it further includes:

[0091] After the new energy load is transferred to the new energy power source, multiple segment loads included in the power grid line load are obtained; based on the multiple segment loads, a segment load transfer line that has a connection relationship with the power grid line and can carry at least one segment load among the multiple segment loads is searched; if a segment load transfer line is found, at least one segment load is gradually transferred to the segment load transfer line according to the connection relationship.

[0092] It is understandable that after the new energy load is transferred to the new energy power source, the load pressure on the opposite side grid line is reduced, and it is capable of carrying the remaining load of the grid line on the pressure-loss side. At this time, the opposite side grid line is searched again for the grid line that can bear the load of the grid line on the pressure-loss side. If it can be found, the grid line load will be transferred to achieve segmented power supply restoration.

[0093] In some possible implementations, the power grid line on the pressure-loss side may be divided into multiple segments. If the load transfer line that carries the load of the entire power grid line cannot be searched, the segment loads can be accumulated segment by segment, and then the segment load transfer line is searched. For example, the power grid line on the pressure-loss side is divided into four segments, which are the first segment, the second segment, the third segment, and the fourth segment from near to far from the opposite power grid line, and the first segment is connected to a new energy power source. The first load transfer first transfers the load of the first segment and the load of the new energy power source to the opposite power grid line. After the new energy power source load transfer is completed and the new energy power source is restored to the grid, the new energy power source load is transferred back to the new energy power source, and the load pressure of the opposite power grid line is reduced. It is searched whether there is a load transfer line that can carry the entire line load of the pressure-loss side line. If not, it is searched whether there is a load transfer line that can carry the loads of the first to third segments. If not, it is searched whether there is a load transfer line that can carry the loads of the first and second segments. If still not, it is detected whether there is a load transfer line that can carry the load of the first segment.

[0094] Furthermore, if a load transfer line is found, power supply is gradually restored based on the connection relationship. For example, if a load transfer line is found that can carry the load of the first to third line segments, the load of the first line segment is transferred first. After power supply to the first line segment is restored, the load of the second line segment is transferred. After power supply to the second line segment is restored, the load of the third line segment is transferred, thereby restoring power supply in stages.

[0095] The load transfer method provided in the embodiment of the present application performs segmented load transfer and phased power supply restoration on the power grid line on the pressure-loss side after the new energy load is transferred to the new energy power supply, so as to ensure the power supply of the power grid line on the pressure-loss side as much as possible.

[0096] In a possible implementation, determining a segment load of a power grid line in a power grid line includes:

[0097] If the power flow direction of the new energy power source is positive, determine the sectional load according to the sum of the new energy load and the sectional power grid line load;

[0098] If the power flow direction of the new energy power source is negative, determine the sectional load according to the difference between the new energy load and the sectional power grid line load.

[0099] Power flow refers to the direction and magnitude of the flow of electricity in the power grid, which is jointly determined by the active power (P) and the reactive power (Q). The power flow direction of the traditional power grid is that centralized power plants such as thermal power plants and hydropower plants supply power unidirectionally to the load center through the transmission network, and the power flow direction is fixed. Distributed new energy power sources such as photovoltaic and wind power are directly connected to the distribution network or the user side, which may change the power flow direction to bidirectional or multi-directional.

[0100] In the power system, the positive and negative of the power flow direction usually take the reference direction as the standard. If the traditional power grid flow direction, that is, from the power generation side to the user side, is taken as the positive direction, then the positive power flow direction of the new energy power source means that the power generation of the distributed power source is greater than the local load demand, and the excess electric energy is fed into the power grid, and this node changes from a "load node" to a "power source node". When the power generation of photovoltaic increases sharply at noon on a sunny day, the wind turbine is fully loaded at a high wind speed, and the user-side power consumption demand is low, the power flow direction of the new energy power source is usually positive. At this time, it is necessary to determine the sectional load according to the sum of the new energy load and the sectional power grid line load. Exemplarily, in Figure 4 In the shown local distribution network model, if the power flow direction of the new energy power source is positive, the load calculation for the rear section of pole #50 on line A3 is 50A of the load carried by switch 50T1 at pole #50, plus 240A of the forward output of photovoltaic 1, for a total of 290A.

[0101] The negative power flow direction of the new energy power source indicates that the power generation of the new energy power source is not enough to meet the local load demand, and electric energy needs to be absorbed from the power grid. For example, when photovoltaic cannot generate electricity at night or on rainy days, or the wind turbine stops rotating at low wind speeds, or the user-side power consumption demand suddenly increases, the power flow direction of the new energy power source is usually negative. Determine the sectional load according to the difference between the new energy load and the sectional power grid line load. Exemplarily, in Figure 4 In the shown local distribution network model, if the power flow direction of the new energy power source is negative, the load calculation for the rear section of pole #50 on line A3 is 240A - 50A = 190A.

[0102] The load transfer method provided by the embodiment of the present application fully considers the power flow direction of the new energy power source when calculating the sectional load, ensuring the accuracy of the sectional load calculation.

[0103] Figure 5 As shown in the structural schematic diagram of the load transfer device provided by the present application, Figure 5 As shown, the load transfer device 50 provided in this embodiment includes:

[0104] A monitoring module 501, configured to monitor whether the substation bus is de-energized, where the power grid lines connected to the substation include new energy power sources;

[0105] An acquisition module 502, configured to, in response to detecting that the bus is de-energized, acquire the total load before the power grid line loses voltage, where the total load before the power grid line loses voltage includes the load of the power grid line and the new energy load carried by the new energy power source;

[0106] A search module 503, configured to search for a total load transfer line that has a connection relationship with the power grid line and can carry the total load before the power grid line loses voltage according to the total load before the power grid line loses voltage;

[0107] A transfer module 504, configured to transfer the total load before the power grid line loses voltage to the total load transfer line if a total load transfer line is searched for.

[0108] In a possible implementation manner, the search module 503 is specifically configured to:

[0109] In the distribution network model, search for a total load transfer line that has a connection relationship with the power grid line and can carry the total load before the power grid line loses voltage according to the total load before the power grid line loses voltage, where the distribution network model includes power source attributes, power grid line connection relationships, and power grid line load information.

[0110] In a possible implementation manner, the search module 503 is specifically configured to:

[0111] Based on the distribution network model, acquire the target load of the opposite-side power grid line that has a connection relationship with the power grid line;

[0112] If the sum of the target load and the total load before the power grid line loses voltage is less than the current limiting value of the opposite-side power grid line, determine the opposite-side power grid line as the total load transfer line.

[0113] In a possible implementation manner, the search module 503 is further configured to:

[0114] If no total load transfer line is searched for, determine the sectional load of the feeder in the power grid line, where the sectional load includes the sectional power grid line load of the rear section of the feeder close to the opposite-side power grid line, and if the feeder is connected to a new energy power source, the sectional load further includes the new energy load;

[0115] Search for a sectional load transfer line that can carry the sectional load according to the sectional load and the line connection relationship;

[0116] If a sectional load transfer line is searched for, transfer the sectional load to the sectional load transfer line.

[0117] In a possible implementation manner, the transfer module 504 is further configured to:

[0118] Detect whether the new energy power source resumes grid connection;

[0119] If it is detected that the new energy has resumed grid connection, control the new energy power source to generate electricity at full capacity, and transfer the new energy load to the new energy power source.

[0120] In a possible implementation, the search module 503 is further configured to:

[0121] After transferring the new energy load to the new energy power source, according to the grid line load, search for a grid line load transfer line that has a connection relationship with the grid line and can carry the grid line load;

[0122] The transfer module is further configured to, if a grid line load transfer line is searched, transfer the grid line load to the grid line load transfer line.

[0123] In a possible implementation, the acquisition module 502 is further configured to:

[0124] If the power flow direction of the new energy power source is positive, determine the sectional load according to the sum of the new energy load and the sectional grid line load;

[0125] If the power flow direction of the new energy power source is negative, determine the sectional load according to the difference between the new energy load and the sectional grid line load.

[0126] The load transfer device provided in this embodiment can execute the method provided in the above method embodiment, and its implementation principle and technical effect are similar, which will not be elaborated here in this embodiment.

[0127] Figure 6 It is a schematic structural diagram of the load transfer device provided in this application. As Figure 6 shown, the electronic device 60 provided in this embodiment includes: at least one processor 601 and a memory 602. Optionally, the device 60 further includes a communication component 603. Among them, the processor 601, the memory 602, and the communication component 603 are connected through a bus 604.

[0128] In the specific implementation process, at least one processor 601 executes the computer execution instructions stored in the memory 602, so that at least one processor 601 executes the above method.

[0129] The specific implementation process of the processor 601 can refer to the above method embodiment, and its implementation principle and technical effect are similar, which will not be elaborated here in this embodiment.

[0130] In the above embodiments, it should be understood that the processor may be a central processing unit (CPU), or may also be other general-purpose processors, digital signal processors (DSPs), application specific integrated circuits (ASICs), etc. The general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc. The steps of the method disclosed in combination with the invention may be directly implemented by a hardware processor or implemented by a combination of hardware and software modules in the processor.

[0131] The memory may include a random access memory (RAM), or may also include non-volatile memory (NVM), such as at least one disk memory.

[0132] The bus may be an industry standard architecture (ISA) bus, a peripheral component interconnect (PCI) bus, an extended industry standard architecture (EISA) bus, etc. The bus may be divided into an address bus, a data bus, a control bus, etc. For ease of representation, the buses in the drawings of this application are not limited to only one bus or one type of bus.

[0133] This application also provides a computer program product, including a computer program, which implements the above method when executed by a processor.

[0134] This application also provides a computer-readable storage medium, in which computer-executable instructions are stored, and when the processor executes the computer-executable instructions, the above method is implemented.

[0135] The above-readable storage medium may be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic memory, flash memory, a magnetic disk or an optical disk. The readable storage medium may be any available medium accessible by a general-purpose or special-purpose computer.

[0136] An exemplary readable storage medium is coupled to a processor, enabling the processor to read information from and write information to the readable storage medium. Of course, the readable storage medium can also be a component of the processor. The processor and the readable storage medium can be located in an Application Specific Integrated Circuits (ASIC). Of course, the processor and the readable storage medium can also exist as discrete components in a device.

[0137] The division of units is only a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Additionally, the couplings or direct couplings or communication connections shown or discussed between each other can be indirect couplings or communication connections through some interfaces, devices or units, and can be in electrical, mechanical or other forms.

[0138] The units described as separate components may or may not be physically separated. The components shown as units may or may not be physical units, that is, they can be located in one place or distributed to multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0139] In addition, in each embodiment of the present invention, the functional units can be integrated in a processing unit, or each unit can exist physically alone, or two or more units can be integrated in one unit.

[0140] If the function is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods in each embodiment of the present invention. The aforementioned storage medium includes: various media such as USB flash drives, mobile hard disks, Read-Only Memory (ROM), Random Access Memory (RAM), magnetic disks, or optical discs that can store program codes.

[0141] Those of ordinary skill in the art will understand that all or part of the steps of implementing the above method embodiments can be completed by hardware related to program instructions. The foregoing program can be stored in a computer-readable storage medium. When the program is executed, it performs the steps of the above method embodiments; and the foregoing storage medium includes: various media such as ROM, RAM, magnetic disks, or optical discs that can store program codes.

[0142] Finally, it should be noted that those skilled in the art will readily conceive of other embodiments of the present invention after considering the specification and practicing the invention disclosed herein. The present invention is intended to cover any variations, uses, or adaptations of the present invention, which follow the general principles of the present invention and include known common knowledge or conventional technical means in the technical field not disclosed in the present invention. It is not limited to the exact structures described above and shown in the drawings, and various modifications and changes can be made without departing from its scope. The scope of the present invention is only limited by the appended claims.

Claims

1. A load transfer method, characterized in that, Including: Monitoring whether the bus of a substation loses voltage, where the power grid lines connected to the substation include new energy power sources; In response to detecting the bus voltage loss, obtaining the total load before the voltage loss of the power grid line, where the total load before the voltage loss includes the power grid line load before the bus voltage loss and the new energy load carried by the new energy power source before it trips off the grid; among them, the power grid line is divided into multiple line segments, and the power grid line load is the sum of the line segment loads of the multiple line segments; According to the total load before the voltage loss, searching for a total load transfer line that has a connection relationship with the power grid line and can carry the total load before the voltage loss; If the total load transfer line is found, transferring the total load before the voltage loss to the total load transfer line.

2. The load transfer method according to claim 1, wherein The step of searching for a total load transfer line that has a connection relationship with the power grid line and can carry the total load before the voltage loss according to the total load before the voltage loss includes: In the distribution network model, according to the total load before the voltage loss, searching for a total load transfer line that has a connection relationship with the power grid line and can carry the total load before the voltage loss, where the distribution network model includes power source attributes, power grid line connection relationships, and power grid line load information.

3. The load transfer method according to claim 2, wherein The step of searching for a total load transfer line that has a connection relationship with the power grid line and can carry the total load before the voltage loss in the distribution network model includes: Based on the distribution network model, obtaining the target load of the opposite-side power grid line that has a connection relationship with the power grid line; If the sum of the target load and the total load before the voltage loss is less than the current-limiting value of the opposite-side power grid line, determining the opposite-side power grid line as the total load transfer line.

4. The load transfer method according to any one of claims 1 to 3, characterized in that, Also including: If the total load transfer line is not found, determining the sectional load of the power grid line, where the sectional load includes the line segment load of the rear section of the power grid line that has a connection relationship with the opposite-side power grid line, and if the power grid line is connected to a new energy power source, the sectional load also includes the new energy load; According to the sectional load and the line connection relationship, searching for a sectional load transfer line that can carry the sectional load; If the sectional load transfer line is found, transferring the sectional load to the sectional load transfer line.

5. The load transfer method according to claim 4, wherein If the power grid line is connected to a new energy power source, the load transfer method further includes: Detecting whether the new energy power source resumes grid connection; If it is detected that the new energy power source has resumed grid connection, controlling the new energy power source to generate electricity at full load and transferring the new energy load to the new energy power source.

6. The load transfer method according to claim 5, characterized in that, Also including: After transferring the new energy load to the new energy power source, obtaining the multiple line segment loads included in the power grid line load; According to the multiple line segment loads, searching for a line segment load transfer line that has a connection relationship with the power grid line and can carry at least one of the multiple line segment loads; If the line segment load transfer line is found, gradually transferring the at least one line segment load to the line segment load transfer line according to the connection relationship.

7. The load transfer method according to claim 4, wherein The step of determining the sectional load of the power grid line includes: If the power flow direction of the new energy power source is positive, determine the sectional load according to the sum of the new energy load and the line load; If the power flow direction of the new energy power source is negative, determine the sectional load according to the difference between the new energy load and the line load.

8. A load transfer device, characterized in that, It includes: A monitoring module, configured to monitor whether the substation bus is de-energized. The power grid lines connected to the substation include new energy power sources; An acquisition module, configured to, in response to detecting that the bus is de-energized, acquire the total load before the power failure of the power grid line. The total load before the power failure includes the power grid line load and the new energy load carried by the new energy power source; A search module, configured to search for a total load transfer line that has a connection relationship with the power grid line and can carry the total load before the power failure according to the total load before the power failure; A transfer module, configured to, if the total load transfer line is searched, transfer the total load before the power failure to the total load transfer line.

9. A load transfer device, characterized in that, It includes: A memory and a processor; The memory stores computer execution instructions; The processor executes the computer execution instructions stored in the memory, so that the processor executes the method according to any one of claims 1-7.

10. A computer-readable storage medium, characterized in that, Computer execution instructions are stored in the computer-readable storage medium. When the computer execution instructions are executed by the processor, they are used to implement the method according to any one of claims 1-7.

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