A power distribution network isolated network operation prediction method and device and storage medium

Abstract

The application discloses a kind of power distribution network in isolated network operation prediction method, device and storage medium, the method comprises: at least one main transformer equipment connected to power distribution network is set to fault state, and isolated network region under current fault state is obtained;According to the first output curve of new energy power supply in isolated network region within the preset fault recovery time, the first maximum active power of new energy power supply is obtained;According to the first maximum active power, and the active load of isolated network region, the power supply capacity value of isolated network region is obtained;According to the power supply capacity value of isolated network region, whether isolated network region has isolated network operation capability is determined.The technical scheme of the embodiment of the application obtains the region information with isolated network operation capability in power distribution network, improves the prediction accuracy of isolated network operation region, improves the prediction efficiency of isolated network operation, and ensures the operation safety of isolated network in power distribution network when main transformer equipment is powered off.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of electric power, and in particular to a method and device for predicting isolated network operation in a power distribution network and a storage medium. BACKGROUND

[0002] In recent years, with the gradual development of new power systems, the installed capacity of new energy continues to increase, and as the power supply of new energy power sources increases, the possibility of isolated network operation in the power distribution network also increases when the main power grid fails.

[0003] In order to ensure the safety of isolated network operation, it is necessary to monitor the operation trend of the power distribution network to predict the possibility of isolated network operation. In the prior art, for isolated network operation prediction, the current operating state of the power distribution network is usually used to manually predict based on the experience of staff.

[0004] However, such a prediction method not only has a large prediction error, but also requires a lot of human resources and has low timeliness, making it difficult to ensure timely prediction of isolated network operation in the power distribution network. Once a power failure occurs, it is difficult to ensure the safe operation of the isolated network in the power distribution network. SUMMARY

[0005] The present application provides a method and device for predicting isolated network operation in a power distribution network and a storage medium to predict whether there is a region in the power distribution network that has isolated network operation capability.

[0006] According to an aspect of the present application, a method for predicting isolated network operation in a power distribution network includes:

[0007] setting at least one main transformer device connected to the power distribution network to a fault state, and obtaining an isolated network region under the current fault state;

[0008] obtaining a first maximum active power of a new energy power source in the isolated network region according to a first output curve of the new energy power source within a preset fault recovery time;

[0009] obtaining a power supply capability value of the isolated network region according to the first maximum active power and an active load of the isolated network region;

[0010] determining whether the isolated network region has isolated network operation capability according to the power supply capability value of the isolated network region.

[0011] According to another aspect of the present application, a device for predicting isolated network operation in a power distribution network is provided, including:

[0012] an isolated network region obtaining module configured to set at least one main transformer device connected to the power distribution network to a fault state, and obtain an isolated network region under the current fault state;

[0013] The first maximum active power acquisition module is configured to acquire a first maximum active power of the new energy power source according to a first output curve of the new energy power source within a preset fault recovery time.

[0014] The power supply capability value acquisition module is configured to acquire a power supply capability value of the islanded network region according to the first maximum active power and an active load of the islanded network region.

[0015] The islanded network operation capability judgment module is configured to determine whether the islanded network region has an islanded network operation capability according to the power supply capability value of the islanded network region.

[0016] According to another aspect of the present application, an electronic device is provided, which comprises:

[0017] at least one processor; and

[0018] a memory connected with the at least one processor in communication; wherein,

[0019] the memory stores a computer program executable by the at least one processor, and the computer program is executed by the at least one processor to enable the at least one processor to execute the prediction method for islanded network operation in a power distribution network according to any one of the embodiments of the present application.

[0020] According to another aspect of the present application, a computer readable storage medium is provided, which stores computer instructions for enabling a processor to implement the prediction method for islanded network operation in a power distribution network according to any one of the embodiments of the present application when executed by the processor.

[0021] The technical solution of the embodiments of the present application acquires the first maximum active power of the new energy power source according to the first output curve of the new energy power source within the preset fault recovery time after setting at least one main transformer device connected with the power distribution network to a fault state, and then acquires the power supply capability value of the islanded network region according to the first maximum active power and the active load of the islanded network region, and finally determines whether the islanded network region has an islanded network operation capability according to the power supply capability value of the islanded network region, so as to acquire the region information of the islanded network region having an islanded network operation capability, improve the prediction accuracy of the islanded network operation region, improve the prediction efficiency of the islanded network operation, and ensure the operation safety of the islanded network in the power distribution network when the main transformer device has a power failure.

[0022] It should be understood that the content described in this part is not intended to identify key or important features of the embodiments of the present application, nor is it used to limit the scope of the present application. Other features of the present application will become apparent from the following description. BRIEF DESCRIPTION OF DRAWINGS

[0023] In order to make the technical solution in the embodiments of the present application clearer, the accompanying drawings needed in the embodiments description will be briefly introduced as follows. Obviously, the accompanying drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without any creative effort on the basis of the accompanying drawings.

[0024] Figure 1 is a flow chart of a prediction method for isolated network operation in a power distribution network according to an embodiment of the present application;

[0025] Figure 2 is a flow chart of a prediction method for isolated network operation in a power distribution network according to an embodiment of the present application;

[0026] Figure 3 is a structural schematic diagram of a prediction device for isolated network operation in a power distribution network according to an embodiment of the present application;

[0027] Figure 4 is a structural schematic diagram of an electronic device for implementing the prediction method for isolated network operation in a power distribution network according to an embodiment of the present application. DETAILED DESCRIPTION

[0028] In order to make the technical solution in the embodiments of the present application clearer, the accompanying drawings needed in the embodiments description will be briefly introduced as follows. Obviously, the accompanying drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without any creative effort on the basis of the accompanying drawings.

[0029] It should be noted that the terms "first", "second", and the like in the description and claims of the present application and the above-mentioned accompanying drawings are used to distinguish similar objects, and do not necessarily indicate a specific order or sequence. It should be understood that the data thus used can be interchanged under appropriate circumstances, so that the embodiments of the present application described herein can be implemented in an order other than that illustrated or described herein. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device including a series of steps or units does not necessarily have to include only those steps or units clearly listed, but can include other steps or units not clearly listed or inherent to the process, method, product or device.

[0030] Embodiment one

[0031] Figure 1A flowchart of a prediction method for island operation of a power distribution network according to an embodiment of the present application is shown in FIG. 1. The embodiment can be applied to predict an area with island operation capability in the power distribution network when a power transmission fault occurs in a main transformer device of the power distribution network. The method can be executed by a prediction device for island operation of the power distribution network. The prediction device for island operation of the power distribution network can be implemented in the form of hardware and / or software. The prediction device for island operation of the power distribution network can be configured in a distribution management system (DMS), and the DMS can be configured in an electronic device such as a server. Figure 1 The method includes the following steps.

[0032] In S101, at least one main transformer device connected to the power distribution network is set to a fault state, and an island area under the current fault state is obtained.

[0033] The main transformer device is a power transmission device (for example, a main transformer) in a power plant and a substation for transmitting power to a power system or a user. Since the power in the power distribution network is transmitted by the main transformer device, the main transformer device can be regarded as a power supply of the power distribution network. When one or more main transformer devices in the power distribution network fail, a large area is powered off, and a new energy power supply in the power distribution network provides power to users in a certain area to form an island micro-grid (i.e., an island network) that is independent of the large power grid.

[0034] The power distribution network is connected to one or more main transformer devices. When different main transformer devices are powered off, the corresponding power-off areas are different. Meanwhile, the power distribution network includes one or more new energy power supplies. Since the distribution positions of the new energy power supplies are different, each power-off area can include one or more new energy power supplies or can not include any new energy power supply. Therefore, according to the topological structure of the power distribution network, the power-off areas when each main transformer device is powered off and the power-off areas when multiple main transformer devices are powered off are obtained in advance. Meanwhile, one or more areas with island operation possibility (i.e., island areas) in each power-off area are obtained. Obviously, the island areas include at least one new energy power supply.

[0035] Specifically, the power grid dispatching master station's distribution network framework model is acquired through the DMS system, which stores the distribution network framework's belonging area, plant station and various device data, such as the plant station's ID (Identity document, identity number) and name, feeder belonging plant station, switch device's two sides' connection point ID, etc. The distribution network framework model is usually saved in a file with a ".XML" suffix. Meanwhile, the power grid dispatching master station's distribution network measurement model is also acquired through the DMS system, which stores device state data, such as feeder active and reactive power, bus voltage, switch remote signaling value, etc. The distribution network measurement model is usually saved in a file with a ".dt" suffix. Based on the above-mentioned various device connection points and device state data, the devices of the same connection point are merged to form a topological node. Then, based on the device type and belonging plant station, the subsystems are divided to form a topological island. The switch device's state is updated through the switch telemetry value. Finally, the topological analysis is realized through the classic depth-first search traversal algorithm. Accordingly, the distribution network connected main transformer device and the new energy power supply in the distribution network are acquired. Then, the respective power cut area corresponding to one or more main transformer device power cut, the number of isolated network areas in each power cut area, and the specific location of each isolated network area are determined.

[0036] Optionally, in the embodiment of the present application, the at least one main transformer device connected to the distribution network is set to a fault state, comprising: acquiring the predicted failure probability of each main transformer device connected to the distribution network according to the historical failure records of each main transformer device; and setting at least one main transformer device connected to the distribution network to a fault state according to the predicted failure probability of each main transformer device. Specifically, the failure probability of each main transformer device is determined according to the historical failure records of each main transformer device. The failure probability can be acquired based on the actual failure times of each main transformer device, or based on the failure days of each main transformer device. In each failure day, the main transformer device may appear one or more times. Thus, the failure probability of each main transformer device is acquired. Then, according to the order from high to low of the failure probability, one or more main transformer devices are set to a fault state in turn, so as to ensure that the main transformer device with a higher failure probability has priority in isolated network operation when it fails,

[0037] S102、According to the first output curve of the new energy power supply in the isolated network area within the preset fault recovery time, the first maximum active power of the new energy power supply is acquired.

[0038] The new energy power supply is a power supply with independent power generation capability in the distribution network, and can provide power supply for users in a certain area; the preset fault recovery time is the pre-set fault recovery time of the main transformer device, different main transformer devices can set the same fault recovery time, or set different fault recovery times according to different types of main transformer devices; the output curve is the value of active power that can be provided by the new energy power supply at each time in a future period of time, which is obtained by the new energy output prediction system according to environmental data such as temperature, illumination and wind speed, and historical output data of the new energy power supply, and reflects the power supply capacity of the new energy power supply; wherein, the abscissa of the output curve is time, and the ordinate is the active power that can be provided by the new energy power supply at the current time; in particular, if the current isolated network region includes multiple new energy power supplies, the output curves of the new energy power supplies are numerically added to obtain the active power provided by all new energy power supplies in the isolated network region at each time in a future period of time.

[0039] S103, obtaining the power supply capacity value of the isolated network region according to the first maximum active power and the active load of the isolated network region.

[0040] The first maximum active power is the maximum value of the active power output by the new energy power supply at a sampling time within the predicted fault recovery time; the active load of the isolated network region is the power consumption load required by all users in the region at a sampling time, since the users in a region are relatively fixed, the above power consumption load can be set as a fixed value, or the predicted active load at each sampling time within the predicted fault recovery time can be obtained according to historical power consumption data, and the active load of the isolated network region can be the average value of the active load at each sampling time, or the maximum value of the active load at each sampling time; the power supply capacity value reflects whether the maximum active load provided by the new energy power supply at a unit sampling time can meet the active load of each user in the isolated network region, and the ratio of the first maximum active power to the active load of the isolated network region can be taken as the power supply capacity value.

[0041] S104, determining whether the isolated network region has isolated network operation capability according to the power supply capacity value of the isolated network region.

[0042] If the first preset threshold is set to be greater than or equal to 1, and the power supply capacity value of the isolated network region is greater than or equal to the first preset threshold, it indicates that the maximum active power of the new energy power supply in the isolated network region at a unit time can meet the active load of the user in the isolated network region, that is, the isolated network region has the power basis for isolated network operation and has the isolated network operation capability. In particular, the first preset threshold can also be set to a value less than 1, for example, the first preset threshold is set to 0.8. At this time, although the first maximum active power is less than the active load of the isolated network region, the new energy power supply obviously cannot meet the active load of the isolated network region, but the reserve power provided by the energy storage element in the isolated network region, combined with the power provided by the new energy power supply, still makes the isolated network region have the isolated network operation capability, further realizing the effective prediction of the isolated network operation in the power distribution network.

[0043] Optionally, in the embodiment of the present application, before the first maximum active power of the new energy power supply is obtained according to the first output curve of the new energy power supply in the isolated network region within the preset fault recovery time, it further comprises: obtaining the second maximum active power of the new energy power supply according to the second output curve of the new energy power supply in the isolated network region within the preset sampling detection time; wherein the preset sampling detection time is less than the preset fault recovery time; if it is determined that the ratio of the second maximum active power to the active load of the isolated network region is less than the first preset threshold, it is determined that the isolated network region does not have the isolated network operation capability; and the first maximum active power of the new energy power supply is obtained according to the first output curve of the new energy power supply in the isolated network region within the preset fault recovery time, which comprises: if it is determined that the ratio of the second maximum active power to the active load of the isolated network region is greater than or equal to the first preset threshold, the first maximum active power of the new energy power supply is obtained according to the first output curve of the new energy power supply in the isolated network region within the preset fault recovery time.

[0044] Specifically, when the main network encounters a large-scale power failure, the main transformer device usually needs a long time (for example, 6-8 hours) to restore power supply, and the preset fault recovery time is also usually set to a long time according to the actual situation. The output curve of the new energy is determined by many factors. The longer the prediction time is, the longer the waiting time is, and the prediction accuracy will also be reduced. Therefore, the maximum active power (i.e. the second maximum active power) of the output curve (i.e. the second output curve) within a short time (for example, 10 minutes) is obtained first. If the ratio of the second maximum active power to the active load of the isolated network region is less than the first preset threshold, it is determined that the isolated network region does not have the isolated network operation capability, thereby improving the prediction efficiency of the isolated network operation. If the ratio of the second maximum active power to the active load of the isolated network region is greater than or equal to the first preset threshold, the power supply capacity value within the predicted fault recovery time is continued to be obtained.

[0045] The technical scheme of the embodiment of the present application sets at least one main transformer device connected to the power distribution network to a fault state, acquires the first maximum active power of the new energy power source according to the first output curve of the new energy power source in the islanded network region within the preset fault recovery time, further acquires the power supply capability value of the islanded network region according to the first maximum active power and the active load of the islanded network region, and finally determines whether the islanded network region has islanded network operation capability according to the power supply capability value of the islanded network region, so as to acquire the region information of the power distribution network having islanded network operation capability, improve the prediction accuracy of the islanded network operation region, improve the prediction efficiency of the islanded network operation, and ensure the operation safety of the islanded network in the power distribution network when the main transformer device has a power failure.

[0046] Embodiment two

[0047] Figure 2 A flowchart of a prediction method for islanded network operation in a power distribution network is provided in the second embodiment of the present application. After it is determined that the power supply capability value of the islanded network region is greater than or equal to the first preset threshold, the power supply balance value of the islanded network region is further acquired in this embodiment based on the above-mentioned embodiment. As shown in the figure, Figure 2 the method comprises:

[0048] S201, setting at least one main transformer device connected to the power distribution network to a fault state, and acquiring an islanded network region under the current fault state.

[0049] S202, acquiring the first maximum active power of the new energy power source according to the first output curve of the new energy power source in the islanded network region within the preset fault recovery time.

[0050] S203, acquiring the power supply capability value of the islanded network region according to the first maximum active power and the active load of the islanded network region.

[0051] S204, if it is determined that the power supply capability value of the islanded network region is greater than or equal to the first preset threshold, acquiring the power supply balance value according to the active power of the new energy power source and the active load of the islanded network region at each sampling time within the preset fault recovery time.

[0052] As an autonomous power system, the island micro-grid guarantees the balance between the active power of power supply and the active load in the grid at any time, which is the key to keep the grid safe and reliable operation. The power supply balance value represents the average balance degree of the active power and the active load at each power supply time. The smaller the power supply balance value is, the higher the balance degree is, that is, the closer the values of the two are. First, the difference between the active power of the new energy power supply and the active load of the island grid area, and the ratio of the active power of the new energy power supply, are taken as the initial power supply balance value at this time. Then, the initial power supply balance value at each time is accumulated, and the quotient of the accumulation result and the predicted fault recovery time is the power supply balance value. The specific expression is as follows:

[0053]

[0054] Wherein, τ represents the power supply balance value, P total (t) is the active power of the new energy power supply at t time, P LD (t) represents the active load of the island grid area at t time, t max is the predicted fault recovery time; Obviously, the most ideal power supply mode is that P total (t) is equal to P LD (t) at any time, which means that the active power of the new energy power supply exactly meets the active load of the island grid area at any time, and there is no power supply shortage phenomenon or power surplus phenomenon.

[0055] S205, if it is determined that the power supply balance value is less than the second preset threshold value, it is determined that the island grid area has the island operation capability.

[0056] If the absolute value of the power supply balance value is small (i.e. less than the third preset threshold value), it means that the active power and the active load are relatively balanced. Even if there is a power supply shortage phenomenon, the insufficient power can be made up by the release of the energy storage element. Similarly, even if there is a power supply surplus phenomenon, the excess power can be stored by the charging of the energy storage element.

[0057] S206, if it is determined that the power supply capability value of the island grid area is less than the first preset threshold value, or the power supply balance value is greater than or equal to the second preset threshold value, it is determined that the island grid area does not have the island operation capability.

[0058] If the power supply capability value of the island grid area is less than the second preset threshold value, it means that even if the reserve power provided by the energy storage element in the island grid area is combined with the power provided by the new energy power supply, it still cannot meet the active load in the island grid area. If the power supply balance value is greater than or equal to the third preset threshold value, it means that the active power of the new energy power supply and the active load of the region are unbalanced, and there is a serious power shortage or power surplus phenomenon. At this time, it can also be determined that the current island grid area does not have the island operation capability.

[0059] Optionally, in the embodiments of the present application, after determining that the power supply capacity value of the isolated network region is greater than or equal to the first preset threshold, the method further comprises: obtaining the sum of active power of the new energy power supply and the sum of active load of the isolated network region within the preset fault recovery time; if it is determined that the sum of active power of the new energy power supply is less than the sum of active load of the isolated network region within the preset fault recovery time, it is determined that the isolated network region does not have the isolated network operation capability; and the obtaining of the power supply balance value according to the active power of the new energy power supply and the active load of the isolated network region at each sampling time within the preset fault recovery time comprises: if the sum of active power of the new energy power supply is greater than or equal to the sum of active load of the isolated network region within the preset fault recovery time, the power supply balance value is obtained according to the active power of the new energy power supply and the active load of the isolated network region at each sampling time within the preset fault recovery time.

[0060] Specifically, one prerequisite for the isolated network region having the isolated network operation capability is that the sum of active power of the new energy power supply is greater than or equal to the sum of active load of the isolated network region, so as to ensure that the new energy power supply can meet the total load demand of the isolated network region when the electric energy in the energy storage element is insufficient; and the prerequisite is specifically represented by the following formula:

[0061]

[0062] wherein, P total (t) is the active power of the new energy power supply at t time, P LD (t) represents the active load of the isolated network region at t time, t max is the predicted fault recovery time; if the sum of active power of the new energy power supply is less than the sum of active load of the isolated network region, it is determined that the isolated network region does not have the isolated network operation capability, at this time, a related prompt that the sum of active power and the sum of active load do not match can be given, so as to maintain the supply-demand balance in the isolated island in real time by adjusting the charge-discharge power of the new energy power supply, and then the adjusted charge-discharge power can be used to determine again whether the current isolated network region has the isolated network operation capability.

[0063] Optionally, in the embodiments of the present application, after determining that the power supply capacity value of the isolated network region is greater than or equal to the first preset threshold, the method further comprises: obtaining the minimum active power of the new energy power supply and the active load of the key information infrastructure in the isolated network region within the preset fault recovery time; if it is determined that the minimum active power of the new energy power supply is less than the active load of the key information infrastructure in the isolated network region, it is determined that the isolated network region does not have isolated network operation capability; and the obtaining of the power supply balance value according to the active power of the new energy power supply and the active load of the isolated network region at each sampling time within the preset fault recovery time comprises: if the minimum active power of the new energy power supply is greater than or equal to the active load of the key information infrastructure in the isolated network region, the power supply balance value is obtained according to the active power of the new energy power supply and the active load of the isolated network region at each sampling time within the preset fault recovery time.

[0064] Specifically, another prerequisite for the isolated network region having isolated network operation capability is that the minimum active power of the new energy power supply is greater than or equal to the active load of the key information infrastructure in the isolated network region, which is specifically represented by the following formula:

[0065] minP total (t)≥β i P LD (t)

[0066] Wherein, minP total (t) is the minimum active power in the predicted fault recovery time, P LD (t) represents the active load of the isolated network region at time t, and β i represents the proportion of the active load of the key information infrastructure in the active load of the isolated network region; if the minimum active power of the new energy power supply is less than the active load of the key information infrastructure in the isolated network region, it is determined that the isolated network region does not have isolated network operation capability, at which time a related prompt that the minimum active power does not meet the active load of the key information infrastructure can be issued, so as to divide part or all of the key information infrastructure in the current isolated network region to other isolated network regions, and then whether the current isolated network region has isolated network operation capability can be determined again according to the adjusted isolated network region.

[0067] Optionally, in the embodiment of the present application, after determining that the power supply capability value of the isolated network region is greater than or equal to the first preset threshold, the method further comprises: acquiring voltage amplitudes of each node in the isolated network region and transmission power of each branch; if it is determined that the voltage amplitude of at least one of the nodes is not located in the corresponding voltage limit interval, or the transmission power of at least one of the branches is greater than the corresponding transmission power limit, it is determined that the isolated network region does not have the isolated network operation capability; and the acquiring of the power supply balance value according to the active power of the new energy power supply and the active load of the isolated network region at each sampling time within the preset fault recovery time comprises: if it is determined that the voltage amplitude of each of the nodes is located in the corresponding voltage limit interval, and the transmission power of each of the branches is less than or equal to the corresponding transmission power limit, the power supply balance value is acquired according to the active power of the new energy power supply and the active load of the isolated network region at each sampling time within the preset fault recovery time.

[0068] Specifically, another prerequisite for the isolated network region having the isolated network operation capability is that each node in the isolated network is located in the corresponding voltage limit interval, that is, the node voltage is balanced, and the transmission power of any two nodes connected by a branch in the isolated network is less than or equal to the corresponding transmission power limit, that is, the branch transmission power is balanced; if the voltage amplitude of at least one node is not located in the corresponding voltage limit interval, or the transmission power of at least one branch is greater than the corresponding transmission power limit, it is determined that the isolated network region does not have the isolated network operation capability, at which time a related prompt of node voltage imbalance or branch transmission power imbalance can be given to divide the related nodes and / or branches into other isolated network regions, and then whether the current isolated network region has the isolated network operation capability can be determined again according to the adjusted isolated network region.

[0069] The technical scheme of the embodiment of the present application, after determining that the power supply capability value of the isolated network region is greater than or equal to the first preset threshold, acquires the power supply balance value according to the active power of the new energy power supply and the active load of the isolated network region at each sampling time within the preset fault recovery time, and determines that the isolated network region has the isolated network operation capability when the power supply balance value is less than the second preset threshold, which realizes the supply-demand balance of the active power and the active load in the isolated network operation, avoids the phenomenon of power shortage or power surplus, and further ensures the power supply safety of the isolated network operation region.

[0070] Embodiment three

[0071] Figure 3 A structure schematic diagram of a prediction device for isolated network operation in a power distribution network is provided for the third embodiment of the present application. As shown in the figure, Figure 3 the device comprises:

[0072] The isolated network area acquisition module 310 is configured to set at least one main transformer device connected to the power distribution network to a fault state, and acquire an isolated network area in a current fault state;

[0073] The first maximum active power acquisition module 320 is configured to acquire a first maximum active power of a new energy power source in the isolated network area according to a first output curve of the new energy power source within a preset fault recovery time.

[0074] The power supply capability value acquisition module 330 is configured to acquire a power supply capability value of the isolated network area according to the first maximum active power and an active load of the isolated network area.

[0075] The isolated network operation capability judgment module 340 is configured to determine whether the isolated network area has isolated network operation capability according to the power supply capability value of the isolated network area.

[0076] The technical scheme of the embodiment of the application sets at least one main transformer device connected to the power distribution network to a fault state, acquires a first maximum active power of a new energy power source in the isolated network area according to a first output curve of the new energy power source within a preset fault recovery time, further acquires a power supply capability value of the isolated network area according to the first maximum active power and an active load of the isolated network area, and finally determines whether the isolated network area has isolated network operation capability according to the power supply capability value of the isolated network area, so as to acquire the region information of the power distribution network that has isolated network operation capability, improve the prediction accuracy of the isolated network operation region, improve the prediction efficiency of the isolated network operation, and ensure the operation safety of the isolated network in the power distribution network when the main transformer device has a power failure.

[0077] Optionally, the prediction device for isolated network operation in the power distribution network further comprises:

[0078] The second maximum active power acquisition module is configured to acquire a second maximum active power of the new energy power source in the isolated network area according to a second output curve of the new energy power source within a preset sampling detection time; the preset sampling detection time is less than the preset fault recovery time.

[0079] The first judgment execution module is configured to determine that the isolated network area does not have isolated network operation capability if it is determined that the ratio of the second maximum active power to the active load of the isolated network area is less than a first preset threshold.

[0080] Optionally, the first maximum active power acquisition module 320 is configured to acquire the first maximum active power of the new energy power source in the isolated network area according to the first output curve of the new energy power source within the preset fault recovery time if it is determined that the ratio of the second maximum active power to the active load of the isolated network area is greater than or equal to the first preset threshold.

[0081] Optionally, the isolated network operation capability judging module 340 specifically comprises:

[0082] The power supply balance value obtaining module is configured to, if it is determined that the power supply capability value of the isolated network region is greater than or equal to the first preset threshold, obtain a power supply balance value according to the active power of the new energy power supply and the active load of the isolated network region at each sampling time within the preset fault recovery time.

[0083] The isolated network operation capability judging unit is configured to, if it is determined that the power supply balance value is less than the second preset threshold, determine that the isolated network region has the isolated network operation capability.

[0084] Optionally, the isolated network operation capability judging unit is further configured to, if it is determined that the power supply capability value of the isolated network region is less than the first preset threshold or the power supply balance value is greater than or equal to the second preset threshold, determine that the isolated network region does not have the isolated network operation capability.

[0085] Optionally, the isolated network operation capability judging unit is further configured to, if it is determined that the power supply capability value of the isolated network region is less than the first preset threshold or the power supply balance value is greater than or equal to the second preset threshold, determine that the isolated network region does not have the isolated network operation capability.

[0086] The numerical value sum obtaining module is configured to obtain a sum of the active power of the new energy power supply and a sum of the active load of the isolated network region within the preset fault recovery time.

[0087] The second judging and executing module is configured to, if it is determined that the sum of the active power of the new energy power supply is less than the sum of the active load of the isolated network region within the preset fault recovery time, determine that the isolated network region does not have the isolated network operation capability.

[0088] Optionally, the power supply balance value obtaining module is specifically configured to, if the sum of the active power of the new energy power supply is greater than or equal to the sum of the active load of the isolated network region within the preset fault recovery time, obtain a power supply balance value according to the active power of the new energy power supply and the active load of the isolated network region at each sampling time within the preset fault recovery time.

[0089] Optionally, the isolated network operation capability judging unit is further configured to, if it is determined that the power supply capability value of the isolated network region is less than the first preset threshold or the power supply balance value is greater than or equal to the second preset threshold, determine that the isolated network region does not have the isolated network operation capability.

[0090] The minimum power obtaining module is configured to obtain a minimum active power of the new energy power supply and an active load of a key information infrastructure in the isolated network region within the preset fault recovery time.

[0091] The third judging and executing module is configured to, if it is determined that the minimum active power of the new energy power supply is less than the active load of the key information infrastructure in the isolated network region, determine that the isolated network region does not have the isolated network operation capability.

[0092] Optionally, the power supply balance value acquisition module is specifically configured to acquire the power supply balance value according to the active power of the new energy power supply and the active load of the islanded network region at each sampling time within the preset fault recovery time, if the minimum active power of the new energy power supply is greater than or equal to the active load of the key information infrastructure in the islanded network region.

[0093] Optionally, the islanded network operation prediction device further comprises:

[0094] a node voltage acquisition module, configured to acquire voltage amplitudes of each node in the islanded network region and transmission powers of each branch;

[0095] a fourth judgment and execution module, configured to determine that the islanded network region does not have the islanded network operation capability, if it is determined that the voltage amplitude of at least one of the nodes is not located in the corresponding voltage limit value interval, or the transmission power of at least one of the branches is greater than the corresponding transmission power limit value.

[0096] Optionally, the power supply balance value acquisition module is specifically configured to acquire the power supply balance value according to the active power of the new energy power supply and the active load of the islanded network region at each sampling time within the preset fault recovery time, if it is determined that the voltage amplitude of each of the nodes is located in the corresponding voltage limit value interval, and the transmission power of each of the branches is less than or equal to the corresponding transmission power limit value.

[0097] The islanded network operation prediction device provided by the embodiment of the application can execute the islanded network operation prediction method provided by any embodiment of the application, and has the function modules and beneficial effects corresponding to the execution method.

[0098] Embodiment four

[0099] Figure 4 A structural schematic diagram of an electronic device 10 that can be used to implement embodiments of the application is shown. The electronic device is intended to represent various forms of digital computers, such as laptops, desktops, tablets, personal digital assistants, servers, blade servers, mainframes, and other appropriate computers. The electronic device can also represent various forms of mobile devices, such as personal digital assistants, cellular telephones, smartphones, wearable devices (e.g., headsets, glasses, watches, etc.), and other similar computing devices. The components shown here, their connections and relationships, and their functions, are meant to be examples only, and are not intended to limit the implementations of the applications described and / or claimed in this document.

[0100] As Figure 4As shown, the electronic device 10 includes at least one processor 11, and a memory, such as a read-only memory (ROM) 12, a random access memory (RAM) 13, etc., communicatively connected to the at least one processor 11, where the memory stores computer programs executable by the at least one processor. The processor 11 can perform various appropriate actions and processes according to the computer programs stored in the read-only memory (ROM) 12 or loaded into the random access memory (RAM) 13 from the storage unit 18. In the RAM 13, various programs and data required for the operation of the electronic device 10 can also be stored. The processor 11, the ROM 12, and the RAM 13 are connected to each other through a bus 14. An input / output (I / O) interface 15 is also connected to the bus 14.

[0101] Various components in the electronic device 10 are connected to the I / O interface 15, including an input unit 16, such as a keyboard, a mouse, etc., an output unit 17, such as various types of displays, a speaker, etc., a storage unit 18, such as a magnetic disk, an optical disk, etc., and a communication unit 19, such as a network card, a modem, a wireless communication transceiver, etc. The communication unit 19 allows the electronic device 10 to exchange information / data with other devices through a computer network, such as the Internet, and / or various telecommunication networks.

[0102] The processor 11 can be various general and / or special-purpose processing components with processing and computing capabilities. Some examples of the processor 11 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various special-purpose artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, a digital signal processor (DSP), and any appropriate processor, controller, microcontroller, etc. The processor 11 performs various methods and processes described above, such as the method for predicting islanding operation in a power distribution network.

[0103] In some embodiments, the method for predicting islanding operation in a power distribution network can be implemented as a computer program tangibly embodied in a computer readable storage medium, such as the storage unit 18. In some embodiments, part or all of the computer program can be loaded and / or installed onto the electronic device 10 via the ROM 12 and / or the communication unit 19. When the computer program is loaded into the RAM 13 and executed by the processor 11, one or more steps of the method for predicting islanding operation in a power distribution network described above can be performed. Alternatively, in other embodiments, the processor 11 can be configured to perform the method for predicting islanding operation in a power distribution network by any other appropriate means, such as by means of firmware.

[0104] The various embodiments of the systems and techniques described above can be implemented in digital electronic circuitry, integrated circuitry, a field programmable gate array (FPGA), an application specific integrated circuit (ASIC), a system on a chip (SOC), a load programmable logic device (CPLD), computer hardware, firmware, software, and / or combinations thereof. These various embodiments can include implementation in one or more computer programs that are executable and / or interpretable on a programmable system including at least one programmable processor, which can be special or general purpose, coupled to receive data and instructions from, and to transmit data and instructions to, a storage system, at least one input device, and at least one output device.

[0105] Computer programs used to implement the processes of the application can be written in any combination of one or more programming languages. These computer programs can be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus, such that the computer program, when executed, can cause instructions defined in the flow charts and / or block diagrams to be implemented. The computer program can be executed entirely on a machine, partially on a machine, partially on a machine as a standalone software package and partially on a remote machine or entirely on a remote machine or server.

[0106] In the context of the present application, a computer-readable storage medium can be a tangible medium that can contain or store computer programs for use by or in connection with an instruction execution system, apparatus, or device. Computer-readable storage media can include, but are not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination of the foregoing. Alternatively, a computer-readable storage medium can be a machine-readable signal medium. More specific examples of the machine-readable storage medium will include one or more lines of electrical connections, portable computer disks, hard disk drives, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or Flash memory), optical fibers, portable compact disc read-only memories (CD-ROMs), optical storage devices, magnetic storage devices, or any suitable combination of the foregoing.

[0107] To provide for interaction with a user, the systems and techniques described here can be implemented on an electronic device having a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to the user and a keyboard and a pointing device (e.g., a mouse or a trackball) by which the user can provide input to the electronic device. Other kinds of devices can be used to provide for interaction with a user as well; for example, feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user can be received in any form, including acoustic, speech, or tactile input.

[0108] The systems and techniques described here can be implemented in a computing system that includes a back end component (e.g., as a data server), or that includes a middleware component (e.g., an application server), or that includes a front end component (e.g., a user computer having a graphical user interface or a Web browser through which a user can interact with an implementation of the systems and techniques described here), or any combination of such back end, middleware, or front end components. The components of the system can be interconnected by any form or medium of digital data communication (e.g., a communication network). Examples of communication networks include a local area network (LAN), a wide area network (WAN), a blockchain network, and the Internet.

[0109] The computing system can include clients and servers. A client and server are generally remote from each other and typically interact through a communication network. The relationship of client and server arises by virtue of computer programs running on the respective computers and having a client-server relationship to each other. A server can be a cloud server, also known as a cloud computing server or cloud host, which is a host product in the cloud computing service system, to solve the defects of large management difficulty and weak business scalability in traditional physical host and VPS service.

[0110] It should be understood that the various forms of flow shown above can be re-ordered, added to, or deleted from without departing from the scope of the present disclosure. For example, the steps recited in the present disclosure can be executed in parallel, executed in sequence, or executed in a different order, as long as the desired results of the present disclosure are achieved, and the present disclosure is not limited herein.

[0111] The specific embodiments described above are not intended to be limiting, and persons skilled in the art will appreciate that various modifications, combinations, sub-combinations and alternatives can be made to the specific embodiments without departing from the spirit and principles of the disclosure. Accordingly, the disclosure is not limited to the specific embodiments described above, but only by the scope of the appended claims.

Claims

1. A method for predicting islanded operation in a distribution network, characterized in that, include: Set at least one main transformer connected to the distribution network to a fault state and obtain the isolated network area under the current fault state; Based on the second output curve of the new energy power source in the isolated grid area within a preset sampling and detection time, the second maximum active power of the new energy power source is obtained; wherein, the preset sampling and detection time is less than the preset fault recovery time; If the ratio of the second maximum active power to the active load of the isolated grid area is less than the first preset threshold, then the isolated grid area is determined to lack the capability for isolated grid operation. If the ratio of the second maximum active power to the active load of the isolated grid area is determined to be greater than or equal to the first preset threshold, then the first maximum active power of the new energy power source is obtained according to the first output curve of the new energy power source in the isolated grid area within the preset fault recovery time. Based on the first maximum active power and the active load of the isolated grid area, the power supply capacity value of the isolated grid area is obtained; Based on the power supply capacity value of the isolated grid area, determine whether the isolated grid area has the capability to operate as an isolated grid; The step of determining whether the isolated grid area has the capability to operate as an isolated grid based on the power supply capacity value of the isolated grid area includes: If it is determined that the power supply capacity of the isolated grid area is greater than or equal to the first preset threshold, then the power supply balance value is obtained based on the active power of the new energy source and the active load of the isolated grid area at each sampling time within the preset fault recovery time. The power supply balance value is obtained by taking the ratio of the difference between the active power of the new energy source and the active load of the isolated grid area to the active power of the new energy source as the initial power supply balance value at that time, and then accumulating the initial power supply balance values ​​at each time, and obtaining the quotient of the accumulation result and the predicted fault recovery time. If the power supply balance value is determined to be less than the second preset threshold, then the isolated grid area is determined to have the capability to operate in an isolated grid.

2. The method according to claim 1, characterized in that, The step of determining whether the isolated grid area has the capability to operate in an isolated grid based on the power supply capacity value of the isolated grid area further includes: If the power supply capacity of the isolated grid area is determined to be less than a first preset threshold, or the power supply balance value is greater than or equal to a second preset threshold, then the isolated grid area is determined to lack the capability for isolated grid operation.

3. The method according to claim 2, characterized in that, After determining that the power supply capacity of the isolated grid area is greater than or equal to a first preset threshold, the method further includes: Obtain the total active power of the new energy power source and the total active load of the isolated grid area within the preset fault recovery time. If it is determined that the total active power of the new energy power source is less than the total active load of the isolated grid area within the preset fault recovery time, then it is determined that the isolated grid area does not have the capability for isolated grid operation. The step of obtaining the power supply balance value based on the active power of the new energy source and the active load of the isolated grid area at each sampling time within the preset fault recovery time includes: If the total active power of the new energy power source is greater than or equal to the total active load of the isolated grid area within the preset fault recovery time, then the power supply balance value is obtained based on the active power of the new energy power source and the active load of the isolated grid area at each sampling time within the preset fault recovery time.

4. The method according to claim 2, characterized in that, After determining that the power supply capacity of the isolated grid area is greater than or equal to a first preset threshold, the method further includes: Obtain the minimum active power of the new energy power source and the active load of the critical information infrastructure in the isolated grid area within the preset fault recovery time. If the minimum active power of the new energy power source is determined to be less than the active load of the critical information infrastructure in the isolated grid area, then the isolated grid area is determined to lack the capability for isolated grid operation. The step of obtaining the power supply balance value based on the active power of the new energy source and the active load of the isolated grid area at each sampling time within the preset fault recovery time includes: If the minimum active power of the new energy power source is greater than or equal to the active load of the critical information infrastructure in the isolated grid area, then the power supply balance value is obtained based on the active power of the new energy power source and the active load of the isolated grid area at each sampling time within the preset fault recovery time.

5. The method according to claim 2, characterized in that, After determining that the power supply capacity of the isolated grid area is greater than or equal to a first preset threshold, the method further includes: Obtain the voltage amplitude of each node and the transmission power of each branch in the isolated network area; If it is determined that the voltage amplitude of at least one of the nodes is not within the corresponding voltage limit range, or the transmission power of at least one of the branches is greater than the corresponding transmission power limit, then it is determined that the isolated network area does not have the capability to operate in an isolated network. The step of obtaining the power supply balance value based on the active power of the new energy source and the active load of the isolated grid area at each sampling time within the preset fault recovery time includes: If it is determined that the voltage amplitude of each node is within the corresponding voltage limit range, and the transmission power of each branch is less than or equal to the corresponding transmission power limit, then the power supply balance value is obtained based on the active power of the new energy power source and the active load of the isolated grid area at each sampling time within the preset fault recovery time.

6. A predictive device for islanded operation in a distribution network, characterized in that, include: The isolated network area acquisition module is used to set at least one main transformer device connected to the distribution network to a fault state and acquire the isolated network area under the current fault state. The second maximum active power acquisition module is used to acquire the second maximum active power of the new energy power source based on the second output curve of the new energy power source in the isolated grid area within a preset sampling and detection time; wherein the preset sampling and detection time is less than the preset fault recovery time. The first judgment and execution module is used to determine that the isolated grid area does not have the capability to operate in an isolated grid if the ratio of the second maximum active power to the active load of the isolated grid area is less than a first preset threshold. The first maximum active power acquisition module is used to acquire the first maximum active power of the new energy power source based on the first output curve of the new energy power source in the isolated grid area within a preset fault recovery time if the ratio of the second maximum active power to the active load of the isolated grid area is greater than or equal to the first preset threshold. The power supply capacity value acquisition module is used to acquire the power supply capacity value of the isolated grid area based on the first maximum active power and the active load of the isolated grid area. The isolated grid operation capability determination module is used to determine whether the isolated grid area has the capability to operate in an isolated grid based on the power supply capability value of the isolated grid area. The isolated network operation capability assessment module specifically includes: The power supply balance value acquisition module is used to acquire a power supply balance value based on the active power of the new energy source and the active load of the isolated grid area at each sampling time within the preset fault recovery time if the power supply capacity value of the isolated grid area is determined to be greater than or equal to a first preset threshold. The power supply balance value is obtained by taking the ratio of the difference between the active power of the new energy source and the active load of the isolated grid area to the active power of the new energy source as the initial power supply balance value at that time, and then accumulating the initial power supply balance values ​​at each time, and obtaining the quotient of the accumulation result and the predicted fault recovery time. An isolated grid operation capability determination unit is used to determine that the isolated grid area has isolated grid operation capability if the power supply balance value is less than a second preset threshold.

7. An electronic device, characterized in that, The electronic device includes: At least one processor; and A memory communicatively connected to the at least one processor; wherein, The memory stores a computer program that can be executed by the at least one processor, the computer program being executed by the at least one processor to enable the at least one processor to perform the prediction method for islanded operation in the distribution network according to any one of claims 1-5.

8. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer instructions that, when executed by a processor, implement the prediction method for islanded operation in a distribution network as described in any one of claims 1-5.

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