Power system load shedding method and device, computer equipment and storage medium

Abstract

The invention relates to a power system load shedding method and device, computer equipment and a storage medium. Acquiring a system operation state of the power system in the target time period; acquiring sample data of the observation node from historical operation data of the power system according to the system operation state; according to the sample data of the observation node, the operation installed capacity of each generator set observed by the observation node in the target time period, and the operation installed capacity of each generator set in the power system, determining the equivalent estimation inertia of the power system in the target time period; and according to the equivalent estimation inertia, the rated frequency of the power system, the frequency change rate before and after load shedding and the preset load shedding amount before load shedding, carrying out multi-round load shedding on the power system. Therefore, each turn of determination of the load shedding amount of the power system is more accurate, and the stability of the power system is improved.

Description

Technical Field

[0001] The present application relates to the technical field of electric power, and particularly to a method and device for load shedding in an electric power system, a computer device, and a storage medium. Background Art

[0002] As the third line of defense for the safe and stable operation of an electric power system, low-frequency load shedding is an important technical means to prevent the stability of the electric power system from being damaged and large-scale power outages after suffering severe faults.

[0003] In traditional technologies, the power deficit is usually determined based on the equivalent inertia of the power system, and then the load shedding amount is determined based on the power deficit. However, with the increase in new energy power generation facilities in the power system, it is difficult to accurately calculate the equivalent inertia, resulting in inaccurate determination of the power deficit, inaccurate determination of the load shedding amount, and low stability of the power system. Summary of the Invention

[0004] Based on this, in view of the above technical problems, it is necessary to provide a method and device for load shedding in an electric power system, a computer device, and a storage medium, which can accurately calculate the equivalent inertia and improve the stability of the electric power system.

[0005] In a first aspect, the present application provides a method for load shedding in an electric power system, including:

[0006] Obtain the system operation state of the power system in a target time period; wherein, the system operation state at least includes the operating installed capacity of various generating units in the power system and the system load;

[0007] According to the system operation state, obtain the sample data of the observation nodes from the historical operation data of the power system; wherein, the sample data is the historical operation data corresponding to the historical time period with the same system operation state as the target time period;

[0008] Determine the equivalent estimated inertia of the power system in the target time period according to the sample data of the observation nodes, the operating installed capacity of various generating units observed by the observation nodes in the target time period, and the operating installed capacity of various generating units in the power system;

[0009] Perform multiple rounds of load shedding on the power system according to the equivalent estimated inertia, the rated frequency of the power system, the frequency change rate before and after load shedding, and the preset load shedding amount before load shedding.

[0010] In one of the embodiments, there are at least two observation nodes. Determining the equivalent estimated inertia of the power system in the target time period according to the sample data of the observation nodes, the operating installed capacity of various generating units observed by the observation nodes in the target time period, and the operating installed capacity of various generating units in the power system includes:

[0011] Determine the equivalent estimated inertia of each observation node during the target period according to the sample data of each observation node;

[0012] For each observation node, take the product of the equivalent estimated inertia of the observation node during the target period and the operating installed capacity of various generator sets observed by the observation node during the target period as an intermediate value;

[0013] Take the ratio of the sum of the intermediate values corresponding to each observation node to the operating installed capacity of various generator sets in the power system as the equivalent estimated inertia of the power system during the target period.

[0014] In one embodiment, determining the equivalent estimated inertia of each observation node during the target period according to the sample data of each observation node includes:

[0015] For each observation node, according to the preset interference frequency, screen out the target sample data of a single interference event from the sample data of the observation node;

[0016] Fit the frequency sample data in the target sample data to obtain the frequency change rate of the observation node at the moment of a single interference event;

[0017] Determine the equivalent estimated inertia of the observation node at the moment of a single interference event according to the frequency change rate and power change rate of the observation node at the moment of a single interference event;

[0018] Take the average value of the equivalent estimated inertia of the observation node at the moments of a preset number of single interference events as the equivalent estimated inertia of the observation node during the target period.

[0019] In one embodiment, perform multiple rounds of load shedding on the power system according to the equivalent estimated inertia, the rated frequency of the power system, the frequency change rate before and after load shedding, and the preset load shedding amount before load shedding, including:

[0020] For each round, determine the first ratio of the equivalent estimated inertia corresponding to the round to the rated frequency of the power system;

[0021] Take the product of the first ratio and the frequency change rate before the round of load shedding as the actual power deficit before the round of load shedding; wherein, the equivalent estimated inertia of the first round is the equivalent estimated inertia of the power system during the target period, and the equivalent estimated inertia of each subsequent round is determined according to the load shedding amount of the previous round, the rated frequency of the power system, and the frequency change rate before and after each round of load shedding; the load shedding amount of the previous round is determined according to the actual power deficit before and after the previous round of load shedding;

[0022] Perform the round of load shedding on the power system according to the actual power deficit before the round of load shedding and the preset load shedding amount before the round of load shedding.

[0023] In one embodiment, according to the actual power deficit before round-by-round load shedding and the preset load shedding amount before load shedding, the power system is subjected to round-by-round load shedding, including:

[0024] If the actual power deficit before round-by-round load shedding is greater than or equal to the preset load shedding amount before round-by-round load shedding, the power system is load-shedded according to the preset load shedding amount before round-by-round load shedding;

[0025] If the actual power deficit before round-by-round load shedding is less than the preset load shedding amount before round-by-round load shedding, the power system is load-shedded according to the actual power deficit.

[0026] In one embodiment, the power system includes various alternative load nodes for load shedding. According to the actual power deficit before round-by-round load shedding and the preset load shedding amount before load shedding, the power system is subjected to round-by-round load shedding, including:

[0027] Each alternative load node is scored according to its importance, voltage sensitivity, equivalent estimated inertia, unit load shedding cost, and average load rate to obtain the comprehensive score of each alternative load node;

[0028] According to the principle that the lower the comprehensive score of each alternative load node, the more load shedding amount is allocated, the power system is subjected to round-by-round load shedding for each alternative load node in the power system according to the actual power deficit before round-by-round load shedding and the preset load shedding amount before load shedding.

[0029] In a second aspect, the present application further provides a power system load shedding device, including:

[0030] A first acquisition module for acquiring the system operation state of the power system in a target time period; wherein, the system operation state at least includes the operating installed capacity of various generator sets in the power system and the system load;

[0031] A second acquisition module for acquiring sample data of the observation nodes from the historical operation data of the power system according to the system operation state; wherein, the sample data is the historical operation data corresponding to the historical time period with the same system operation state as the target time period;

[0032] A determination module for determining the equivalent estimated inertia of the power system in the target time period according to the sample data of the observation nodes, the operating installed capacity of various generator sets observed by the observation nodes in the target time period, and the operating installed capacity of various generator sets in the power system;

[0033] A load shedding module for performing multi-round load shedding on the power system according to the equivalent estimated inertia, the rated frequency of the power system, the frequency change rate before and after load shedding, and the preset load shedding amount before load shedding.

[0034] In a third aspect, the present application further provides a computer device, including a memory and a processor. The memory stores a computer program, and when the processor executes the computer program, the following steps are implemented:

[0035] Obtain the system operation state of the power system during a target period; wherein, the system operation state at least includes the operating installed capacity of various generating units in the power system and the system load;

[0036] According to the system operation state, obtain the sample data of the observation nodes from the historical operation data of the power system; wherein, the sample data is the historical operation data corresponding to the historical period with the same system operation state as that of the target period;

[0037] Determine the equivalent estimated inertia of the power system during the target period according to the sample data of the observation nodes, the operating installed capacity of various generating units observed by the observation nodes during the target period, and the operating installed capacity of various generating units in the power system;

[0038] Perform multiple rounds of load shedding on the power system according to the equivalent estimated inertia, as well as the rated frequency of the power system, the frequency change rate before and after load shedding, and the preset load shedding amount before load shedding.

[0039] In a fourth aspect, the present application further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the following steps are implemented:

[0040] Obtain the system operation state of the power system during a target period; wherein, the system operation state at least includes the operating installed capacity of various generating units in the power system and the system load;

[0041] According to the system operation state, obtain the sample data of the observation nodes from the historical operation data of the power system; wherein, the sample data is the historical operation data corresponding to the historical period with the same system operation state as that of the target period;

[0042] Determine the equivalent estimated inertia of the power system during the target period according to the sample data of the observation nodes, the operating installed capacity of various generating units observed by the observation nodes during the target period, and the operating installed capacity of various generating units in the power system;

[0043] Perform multiple rounds of load shedding on the power system according to the equivalent estimated inertia, as well as the rated frequency of the power system, the frequency change rate before and after load shedding, and the preset load shedding amount before load shedding.

[0044] In a fifth aspect, the present application further provides a computer program product, including a computer program. When the computer program is executed by a processor, the following steps are implemented:

[0045] Obtain the system operation status of the power system during the target period; wherein, the system operation status at least includes the operating installed capacity of various generator sets in the power system and the system load;

[0046] According to the system operation status, obtain the sample data of the observation nodes from the historical operation data of the power system; wherein, the sample data is the historical operation data corresponding to the historical period with the same system operation status as the target period;

[0047] According to the sample data of the observation nodes, the operating installed capacity of various generator sets observed by the observation nodes during the target period, and the operating installed capacity of various generator sets in the power system, determine the equivalent estimated inertia of the power system during the target period;

[0048] According to the equivalent estimated inertia, as well as the rated frequency of the power system, the frequency change rates before and after load shedding, and the preset load shedding amount before load shedding, perform multiple rounds of load shedding on the power system.

[0049] The above power system load shedding method, device, computer device and storage medium obtain the system operation status of the power system during the target period; and according to the system operation status, obtain the sample data of the observation nodes from the historical operation data of the power system; and according to the sample data of the observation nodes, the operating installed capacity of various generator sets observed by the observation nodes during the target period, and the operating installed capacity of various generator sets in the power system, determine the equivalent estimated inertia of the power system during the target period; and then perform multiple rounds of load shedding on the power system according to the equivalent estimated inertia, as well as the rated frequency of the power system, the frequency change rates before and after load shedding, and the preset load shedding amount before load shedding. The above solution first determines the equivalent estimated inertia of the power system during the target period according to the sample data of the observation nodes, the operating installed capacity of various generator sets of the observation nodes during the target period, and the operating installed capacity of various generator sets in the power system, so that the determined equivalent estimated inertia of the power system during the target period is relatively reliable; and then makes the load shedding amount determined for each round of the power system more accurate, thereby making the power system more stable. Description of the Drawings

[0050] In order to more clearly illustrate the technical solutions in the embodiments of the present application or related technologies, the following will briefly introduce the drawings required for use in the description of the embodiments of the present application or related technologies. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other related drawings can also be obtained based on these drawings.

[0051] Figure 1 It is a schematic flowchart of the power system load shedding method in an embodiment;

[0052] Figure 2Schematic flowchart of determining the equivalent estimated inertia of a power system during a target period in an embodiment;

[0053] Figure 3 Schematic flowchart of determining the equivalent estimated inertia of each observation node during a target period in an embodiment;

[0054] Figure 4A Schematic flowchart of determining the actual power deficit before load shedding in each round in an embodiment;

[0055] Figure 4B Schematic flowchart of the load shedding process in an embodiment;

[0056] Figure 5 Schematic flowchart of load shedding for a power system in an embodiment;

[0057] Figure 6 Schematic flowchart of load shedding for a power system in another embodiment;

[0058] Figure 7 Schematic diagram of the active - voltage characteristics of alternative load nodes in an embodiment;

[0059] Figure 8 Schematic flowchart of a power system load shedding method in another embodiment;

[0060] Figure 9 Structural block diagram of a power system load shedding device in an embodiment;

[0061] Figure 10 Internal structure diagram of a computer device in an embodiment. Detailed implementation manners

[0062] In order to make the objectives, technical solutions and advantages of the present application clearer and more understandable, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0063] The power system load shedding method provided by the embodiments of this application can be applied to the application scenario of maintaining the stability of the power system by reducing the load after a power system failure. This method can be executed by a server or by a terminal. Among them, the server can be an independent physical server, a server cluster or a distributed system composed of multiple physical servers, or a cloud server providing cloud computing services. The terminal can be, but is not limited to, various personal computers, laptop computers, smart phones, tablet computers, Internet of Things devices, and portable wearable devices. The Internet of Things devices can be smart speakers, smart TVs, smart air conditioners, smart in-vehicle devices, projection devices, etc. The portable wearable devices can be smart watches, smart bracelets, head-mounted devices, etc. The head-mounted devices can be virtual reality (VR) devices, augmented reality (AR) devices, smart glasses, etc.

[0064] In an exemplary embodiment, as Figure 1 shown, a power system load shedding method is provided. Taking the application of this method to a server as an example, the method includes the following steps:

[0065] S101, obtain the system operation status of the power system during the target period.

[0066] Among them, the power system is an electric energy production and consumption system composed of power plants, transmission and transformation lines, power supply and distribution stations, and electricity consumption. The target period T can be a period including the current moment, and the specific duration can be set according to actual needs. For example, it can be set to 1 hour. The system operation status at least includes the operating installed capacity of various types of generator sets in the power system and the system load. The operating installed capacity of various types of generator sets refers to the sum of the rated powers actually put into operation by various types of generator sets at present, and is one of the main indicators used to characterize the current actual power generation capacity of various types of generator sets. The system load can be understood as the power or power taken from the power grid in the power system, as well as the power generated, converted, and consumed by power equipment.

[0067] Exemplarily, monitoring devices can be set in the power system to monitor the system operation status of the power system. The system operation status of the power system during the target period can be obtained through the monitoring devices. For example, various types of generator sets include, but are not limited to, thermal power generator sets, hydropower generator sets, photovoltaic generator sets, and wind power generator sets. The operating installed capacity of various types of generator sets in the power system includes, but is not limited to, the operating installed capacity S T . T of the thermal power generator sets, the operating installed capacity S H . T of the hydropower generator sets, the operating installed capacity S PV . T of the photovoltaic generator sets, and the operating installed capacity SW . T ; The system load is represented by P L . T The system operating state C of the power system in the target time period T is represented as follows:

[0068]

[0069] S102, Obtain the sample data of the observation nodes from the historical operation data of the power system according to the system operating state.

[0070] Among them, the historical operation data of the power system includes the system frequency and system power of the power system at multiple historical moments. The observation node can be understood as any observation node equipped with a Phasor Measurement Unit (PMU) in the power system, which can record the historical operation state data of the power system. It is possible to search in the historical operation data of the power system for the historical time period T H.i whose system operating state is the same as that of the target time period T: . Among them, N is the total number of historical time periods with the same system operating state as the target time period T.

[0071] Furthermore, it is possible to extract the system frequency and system power sequence sample sets recorded by the observation node j within the set , and then the method of low-pass filtering can be used to remove the high-frequency noise in the set data, and the set after removing the noise is used as the sample data of the observation node, that is, the sample data is the historical operation data corresponding to the historical time period with the same system operating state as the target time period. The set is represented as:

[0072]

[0073] N 1 is the total number of system frequency and system power sequence samples; the element v in the set i is the historical system frequency and historical system power sequence of the observation node j, and v i is represented as:

[0074]

[0075] Among them, N 2 is the total number of sample points of the system frequency and system power sequence, t 1 -t N2 is each historical moment within each historical time period, f 1 -fN2 For the system frequencies in each historical period, P 1 -P N2 are the system powers in each historical period.

[0076] S103. Determine the equivalent estimated inertia of the power system in the target period according to the sample data of the observation nodes, the operating installed capacity of various types of generating units observed by the observation nodes in the target period, and the operating installed capacity of various types of generating units in the power system.

[0077] Exemplarily, an equivalent inertia estimation model can be established, which is used to reflect the relational expression between the equivalent estimated inertia of the power system in the target period and the sample data of the observation nodes, the operating installed capacity of various types of generating units of the observation nodes in the target period, and the operating installed capacity of various types of generating units in the power system. Furthermore, an optimization algorithm can be used to solve the equivalent estimated inertia of the power system in the target period.

[0078] It should be noted that the operating installed capacity of the observation nodes in the target period usually refers to the sum of the rated powers of the equipment or systems (such as generating units, substations, etc.) connected to the observation nodes during actual operation in the target period. It reflects the power generation or power supply capacity of the observation nodes in the current operating state.

[0079] The installed capacity of various types of generating units in the power system refers to the sum of the rated output powers of all generating units in the power system, which characterizes the overall power generation capacity and scale of the power system.

[0080] S104. Perform multiple rounds of load shedding on the power system according to the equivalent estimated inertia, the rated frequency of the power system, the frequency change rate before and after load shedding, and the preset load shedding amount before load shedding.

[0081] Exemplarily, the number of load shedding rounds can be preset, and before the start of each round of load shedding, the actual power deficit before each round of load shedding can be determined, and then the load shedding amount for each round can be determined according to the actual power deficit before each round of load shedding.

[0082] Exemplarily, an expression for calculating the actual power deficit can be established, and then the equivalent estimated inertia, the rated frequency of the power system, and the frequency change rate before and after each round of load shedding are substituted into the expression to calculate the actual power deficit before each round of load shedding.

[0083] Exemplarily, the preset load shedding amount for each round can be preset. For example, the preset load shedding amount for the first round can be set to 10% of the load shedding capacity of the power system, and the preset load shedding amount for the second round can be set to 30% of the load shedding capacity of the power system.

[0084] Furthermore, based on the magnitude relationship between the actual power deficit before each round of load shedding and the preset load shedding amount before each round of load shedding, the alternative load nodes can be shed to ensure that the load shedding amount in each round does not exceed the preset load shedding amount in each round, so as to maintain the stability of the power system.

[0085] The above power system load shedding method first determines the equivalent estimated inertia of the power system in the target period based on the sample data of the observation nodes, the operating installed capacity of various generator sets observed by the observation nodes in the target period, and the operating installed capacity of various generator sets in the power system, making the determined equivalent estimated inertia of the power system in the target period more reliable; furthermore, based on the equivalent estimated inertia, the rated frequency of the power system, the frequency change rate before and after each round of load shedding, and the preset load shedding amount before load shedding, the power system is subjected to multiple rounds of load shedding, making the determined load shedding amount for the power system in each round more accurate, thereby making the power system more stable.

[0086] In some alternative implementation manners, the observation nodes can be at least two, and the equivalent estimated inertia of the power system in the target period can be determined according to the equivalent estimated inertia of each observation node in the target period.

[0087] Exemplarily, referring to Figure 2 , Figure 2 a flowchart for determining the equivalent estimated inertia of the power system in the target period is provided, which specifically includes the following steps:

[0088] S201, determine the equivalent estimated inertia of each observation node in the target period according to the sample data of each observation node.

[0089] Exemplarily, the frequency sequence data, power sequence data of the observation nodes, and the equivalent estimated inertia of the observation nodes can be used to train the model in advance to obtain a model that can be used to predict the equivalent estimated inertia of the observation nodes. Among them, the model can be a linear regression model, a non-linear regression model, a machine learning algorithm model (such as a support vector machine, a neural network, etc.).

[0090] Furthermore, the sample data of each observation node can be input into the trained model to predict the equivalent estimated inertia of each observation node in the target period. Among them, the sample data input into the trained model can be the frequency sequence data and power sequence data of each observation node.

[0091] S202, for each observation node, determine the product of the equivalent estimated inertia of the observation node in the target period and the operating installed capacity of various generator sets of the observation node in the target period as an intermediate value.

[0092] Exemplarily, for each observation node, the equivalent estimated inertia of each observation node in the target period can be calculated with the operating installed capacity S of various generator sets of the observation node in the target period j of the product , and take this product as an intermediate value.

[0093] S203, take the ratio of the sum of the intermediate values corresponding to each observation node to the operating installed capacity of various generator sets in the power system as the equivalent estimated inertia of the power system in the target period.

[0094] Furthermore, the ratio of the sum of the intermediate values corresponding to each observation node to the operating installed capacity of various generator sets in the power system can be taken as the equivalent estimated inertia of the power system in the target period. That is, the expression of the equivalent estimated inertia of the power system in the target period is as follows:

[0095]

[0096] where M eq is the equivalent estimated inertia of the power system in the target period, q is the number of observation nodes, and S total is the operating installed capacity of various generator sets in the power system in the target period.

[0097] In the embodiments of the present application, by determining the equivalent estimated inertia of each observation node in the target period and determining the equivalent estimated inertia of the power system in the target period according to the equivalent estimated inertia of each observation node in the target period, compared with determining the equivalent estimated inertia of the power system by using the equivalent estimated inertia of a single observation node, the accuracy of determining the equivalent estimated inertia of the power system is improved.

[0098] In some optional implementation manners, the equivalent estimated inertia of each observation node can be determined according to the frequency sequence data in the sample data.

[0099] Exemplarily, referring to Figure 3 , Figure 3 provides a flow schematic diagram for determining the equivalent estimated inertia of each observation node in the target period, which specifically includes the following steps:

[0100] S301, for each observation node, according to the preset interference frequency, screen out the target sample data of a single interference event from the sample data of the observation node.

[0101] Exemplarily, during the operation of the power system, interference events represented by fluctuations in the output of various generator sets and load switching often occur. The set in the above embodiments The sample data of the observation node, that is, the sample data is the historical operation data corresponding to the historical period with the same system operation state as the target period. It can be in the set The target sample data corresponding to the occurrence of the interference event can be extracted.

[0102] Exemplarily, the preset interference frequency can be determined according to empirical data. For example, the preset interference frequency can be set to 49.8Hz - 49.5Hz, that is, the sample data with the frequency change range of the observation node between 49.8Hz - 49.5Hz is determined as the target sample data.

[0103] Furthermore, according to the preset interference frequency, the target sample data of a single interference event can be screened out from the sample data of the observation node. For example, for an observation node j, the time when the interference event is detected by the observation node is t d.1 , that is, let t d.1 = 0, extract the frequency and power sequence data of the interference event from the time t d.1 to obtain the target sample data of the observation node j. The target sample data can be understood as the frequency and power sequence sample set of historical interference events. The expression is as follows:

[0104]

[0105] Among them, is the target sample data, is the frequency and power sequence sample of the historical interference event, and N 3 is the total number of frequency and power sequence samples of the historical interference event.

[0106] S302. Fit the frequency sample data in the target sample data of the observation node to obtain the frequency change rate of the observation node at the moment of a single interference event.

[0107] Further, the frequency sequence of a single interference event can be extracted first from the target sample data of the observation node, and the obtained frequency sequence is as follows:

[0108]

[0109] Among them, e is the frequency sequence of a single interference event, t d is each historical moment corresponding to the interference event, f d is each historical frequency at each historical moment corresponding to the interference event, and N 4 is the total number of sample points in the frequency sequence of a single interference event.

[0110] Furthermore, the frequency sample data in the target sample data of the observation node can be fitted to obtain the frequency change rate of the observation node at the moment of a single interference event. Exemplarily, an adaptive-order polynomial can be used to fit the frequency sample data in the target sample data of the observation node, and the specific fitting process is as follows:

[0111] Step 1: Use a polynomial to fit the frequency sequence e:

[0112]

[0113] where a 0 , a 1 , …, a n are the polynomial coefficients, and f j is the frequency response curve of a single interference event of the observation node. Take the first derivative of f j to obtain:

[0114]

[0115] Furthermore, substitute the occurrence time t d.1 of a single interference event of observation node j into the above formula to obtain:

[0116]

[0117] where a 1 is the frequency change rate at the occurrence time of a single interference event of observation node j.

[0118] Step 2: Calculate the first-order term coefficient of the polynomial when the order n = 1, and start fitting with n = 2 as the first round.

[0119] Step 3: After calculating the first-order term coefficient obtained from each round of fitting, set the precision value . If the error between the results of this round and the previous round of fitting is greater than the precision value , that is:

[0120]

[0121] represents that the fitting accuracy is insufficient. At this time, the fitting order can be increased by one order, and the obtained from this round of fitting is selected as the comparison object for the obtained from the next round of fitting.

[0122] Step 4: Repeat the fitting process until the error meets the precision requirements:

[0123]

[0124] At this time, stop fitting and obtain the first-order coefficient of the frequency response curve of the observation node j at the moment of a single interference event , that is, the frequency change rate of the observation node j at the moment of a single interference event.

[0125] S303. Determine the equivalent estimated inertia of each observation node at the moment of a single interference event according to the frequency change rate and power change rate of each observation node at the moment of a single interference event.

[0126] Exemplarily, the equivalent estimated inertia of each observation node at the moment of a single interference event can be determined according to the frequency change rate and power change rate of each observation node at the moment of a single interference event. Taking the observation node j as an example, the expression of the equivalent estimated inertia of the observation node j at the moment of a single interference event is as follows:

[0127]

[0128] where M j is the equivalent estimated inertia of the observation node j at the moment of a single interference event, is the power change value of the observation node j at the moment of a single interference event, is the frequency change rate of the observation node j at the moment of a single interference event.

[0129] S304. Take the average value of the equivalent estimated inertia of the observation node at the moments of a preset number of single interference events as the equivalent estimated inertia of the observation node in the target period.

[0130] Exemplarily, in order to reduce the error of the equivalent estimated inertia of each observation node in the target period, the estimated inertia results under multiple single interference events can be dynamically aggregated, that is, determine the average value of the equivalent estimated inertia of each observation node at the moments of a preset number of single interference events, and take the average value as the equivalent estimated inertia of each observation node in the target period. For example, the preset number can be set according to the actual situation. Taking the preset number as m as an example for illustration. Under m single interference events, the equivalent estimated inertia M j.av of the observation node j in the target period is:

[0131]

[0132] where M j.i is the equivalent estimated inertia of the observation node j under the i-th interference event.

[0133] Exemplarily, if a new interference event is detected by the observation node j, and the equivalent estimated inertia of the (m + 1)-th interference event of the observation node j is M j.m+1 , and perform iterative update on M j.av :

[0134]

[0135] Among them, M j.i+1 is the equivalent estimated inertia under the (i + 1)-th interference event of the observation node j, is the equivalent estimated inertia after iterative update of the observation node j, that is, the equivalent estimated inertia of the observation node j during the target period.

[0136] In the embodiments of the present application, by calculating the equivalent estimated inertia of each observation node at the occurrence moments of multiple single interference events, and taking the average value of the equivalent estimated inertia of each observation node at the occurrence moments of a preset number of single interference events as the equivalent estimated inertia of each observation node during the target period, compared with taking only the equivalent estimated inertia at the occurrence moment of one single interference event as the equivalent estimated inertia of each observation node during the target period, the reliability of the equivalent estimated inertia of each observation node during the target period is improved.

[0137] In some alternative implementation manners, before the start of each round of load shedding, the actual power deficit of each round can be calculated first, and the load shedding amount can be determined according to the actual power deficit of each round, which can improve the accuracy of the load shedding amount of each round.

[0138] Exemplarily, referring to Figure 4A , Figure 4A a schematic flow chart for determining the actual power deficit before each round of load shedding is provided, which specifically includes the following steps:

[0139] S401, for each round, determine the first ratio of the equivalent estimated inertia corresponding to the round to the rated frequency of the power system.

[0140] Exemplarily, the load shedding rounds can be preset. For example, one special round and four basic rounds can be set, and the starting frequency of the special round is set to 49.5 Hz, and the action delay of each special round is set to 15 s; the starting frequencies of the basic rounds are set to 49.4 Hz, 49.2 Hz, 49 Hz, and 48.8 Hz, and the action delay of each basic round is set to 0.2 s.

[0141] Taking the first round as an example for illustration. Determine the first ratio of the equivalent estimated inertia corresponding to the first round to the rated frequency of the power system. The equivalent estimated inertia corresponding to the first round is the equivalent estimated inertia of the power system during the target period, and the determined first ratio is .

[0142] S402, take the product of the first ratio and the frequency change rate before the load shedding of this round as the actual power deficit before the load shedding of this round.

[0143] Taking the special round as an example, the product of the first ratio and the frequency change rate before the load shedding in the special round is taken as the actual power deficit before the load shedding in the special round, and the actual power deficit P before the load shedding in the special round def The expression is as follows:

[0144]

[0145]

[0146] where f N is the rated frequency of the power system, is the frequency change rate before and after the load shedding in the special round, and f j1 is the frequency of the observation node j.

[0147] Among them, the equivalent estimated inertia of the first round is the equivalent estimated inertia of the power system in the target period, and the equivalent estimated inertia of each subsequent round is determined according to the load shedding amount of the previous round, the rated frequency of the power system, and the frequency change rate before and after the load shedding in each round; the load shedding amount of the previous round is determined according to the actual power deficit before and after the load shedding in the previous round.

[0148] Exemplarily, taking the second round as an example, at the moment after the load shedding action of the first round is implemented, the relationship between the load shedding amount and the frequency change rate can be obtained according to the expression of the actual power deficit before the load shedding in the special round:

[0149]

[0150] where P 1 is the load shedding amount of the first round, P def.a is the actual power deficit before the load shedding in the first round, P def.b is the actual power deficit after the load shedding in the first round, is the frequency change rate before and after the load shedding in the first round, is the frequency change rate before and after the load shedding in the first round.

[0151] Based on the above formula, the equivalent estimated inertia M before the load shedding in the second round is obtained eq.new :

[0152]

[0153] Before the load shedding in the second round, the real-time frequency change rate of the power system and M eq.new are substituted into the P def expression to recalculate the actual power deficit before the load shedding in the second round of the power system.

[0154] The calculation process of the actual power deficit before the load shedding in the remaining rounds is the same as the above process and will not be elaborated here.

[0155] S403. Perform staged load shedding on the power system according to the actual power deficit before staged load shedding and the preset load shedding amount before staged load shedding.

[0156] Exemplarily, load shedding can be performed on the power system according to the magnitude relationship between the actual power deficit before the current staged load shedding and the preset load shedding amount before the current staged load shedding, so as to ensure that the load shedding amount in each stage does not exceed the preset load shedding amount in each stage, thereby maintaining the stability of the power system.

[0157] Exemplarily, refer to Figure 4B , Figure 4B A schematic diagram of the load shedding process is provided. Before the load shedding starts, the equivalent estimated inertia of the power system during the target period is determined, and the round number i is set to 1.

[0158] Judge whether the frequency f of the power system is less than the starting frequency of the basic round, and judge whether the rate of change of the frequency of the power system is less than or equal to 0. If both conditions are met, calculate the actual power deficit P def before the first-round load shedding, and start the load shedding to allocate the load shedding amount to each alternative load node; if at least one condition is not met, end the load shedding process.

[0159] Furthermore, judge whether the frequency f of the power system is greater than 49.4 Hz, and judge whether the rate of change of the frequency of the power system is greater than 0. If both conditions are met, delay for 15 seconds, and then continue to judge whether the frequency f of the power system is less than or equal to 49.5 Hz, and judge whether the rate of change of the frequency of the power system is less than or equal to 0. If both conditions are met, start the special round. If the frequency f of the power system does not meet the condition of being less than or equal to 49.5 Hz, and / or the rate of change of the frequency of the power system does not meet the condition of being less than or equal to 0, end the load shedding process.

[0160] If the frequency f of the power system does not meet the condition of being greater than 49.4 Hz, and / or the frequency f of the power system does not meet the condition of being less than or equal to 49.5 Hz, calculate the equivalent estimated inertia M eq.new of the power system before the new round of load shedding, increment i by 1, and re-judge whether the frequency f of the power system is less than the starting frequency of the basic round, and judge whether the rate of change of the frequency of the power system is less than or equal to 0.

[0161] In the embodiments of the present application, by calculating the actual power deficit before each round of load shedding, the load shedding amount for each round is determined according to the actual power deficit before each round of load shedding, so as to improve the control accuracy of the load shedding amount for each round.

[0162] In some alternative implementations, the amount of load shedding allowed for each round of the power system can be preset, and then the actual amount of load shedding can be determined based on the magnitude relationship between the actual power deficit before each round of load shedding and the allowed amount of load shedding.

[0163] Exemplarily, referring to Figure 5 , Figure 5 a flowchart of a process for load shedding of a power system is provided, which specifically includes the following steps:

[0164] S501, if the actual power deficit before round-based load shedding is greater than or equal to the preset load shedding amount before round-based load shedding, then load shedding is performed on the power system according to the preset load shedding amount before round-based load shedding.

[0165] Exemplarily, taking one special round and four basic rounds as an example for illustration. Assume that the preset load shedding amount corresponding to each round is 10%, 30%, 20%, 20%, and 20% of the load shedding amount that the power system can shed.

[0166] For each round, if the actual power deficit before round-based load shedding is greater than or equal to the preset load shedding amount before round-based load shedding, in order to avoid the total load shedding amount of the power system exceeding the load shedding amount that can be shed, in this case, load shedding is performed on the power system according to the preset load shedding amount before round-based load shedding.

[0167] S502, if the actual power deficit before round-based load shedding is less than the preset load shedding amount before round-based load shedding, then load shedding is performed on the power system according to the actual power deficit.

[0168] Exemplarily, if the actual power deficit before round-based load shedding is less than the preset load shedding amount before round-based load shedding, then load shedding is performed on the power system according to the actual power deficit, so that the amount of load shedding can better conform to the operating state of the power system.

[0169] In the embodiments of the present application, by comparing the magnitude of the actual power deficit before each round of load shedding and the allowed amount of load shedding, the actual amount of load shedding for each round is determined, which can avoid the total load shedding amount of the power system exceeding the load shedding amount that can be shed while making the amount of load shedding better conform to the operating state of the power system.

[0170] In some alternative implementations, the power system includes various alternative load nodes for load shedding. Performing load shedding on the power system can be understood as performing load shedding on the alternative load nodes. When performing load shedding on the alternative load nodes, various factors can be considered to score the alternative load nodes, and the amount of load shedding for each alternative load node can be determined according to the score.

[0171] Based on this, referring to Figure 6 , Figure 6 another flowchart of a process for load shedding of alternative load nodes is provided, which specifically includes the following steps:

[0172] S601. Score each alternative load node according to its importance, voltage sensitivity, equivalent estimated inertia, cost per unit load shedding, and average load rate to obtain the comprehensive score of each alternative load node.

[0173] Among them, the alternative load nodes can be determined according to the levels of the load nodes. For example, first determine the distribution lines where the first-level loads such as hospitals, government agencies, and data centers are located. If the distribution lines connected by the load nodes do not include first-level loads, select such nodes as the alternative load nodes for load shedding.

[0174] Exemplarily, each alternative load node can be scored respectively according to its importance, voltage sensitivity, equivalent estimated inertia, cost per unit load shedding, and average load rate, and the comprehensive score of the alternative load node can be determined according to each score.

[0175] For example, when scoring each alternative load node according to its importance, the importance of the alternative load node can be scored according to the proportion of the second-level loads and the third-level loads in the distribution lines connected by the alternative load node. For the nodes with a low proportion of second-level loads, lower scores can be assigned, and more load shedding amounts can be allocated during the load shedding process.

[0176] When scoring each alternative load node according to its voltage sensitivity, refer to Figure 7 , Figure 7 A schematic diagram of the active power-voltage characteristics of an alternative load node is provided. can be used to represent the voltage sensitivity of the alternative load node. From Figure 7 , it can be seen that the near the right vertex (i.e., the "nose point") of the curve is relatively large, that is, the voltage of this node has a relatively high sensitivity to the change in active power. After the load is removed, the voltage can recover relatively quickly, and the active power value of the corresponding node also rises at a relatively fast speed, which has a counteractive effect on the frequency recovery of the power system. Therefore, consider assigning lower scores to the alternative load nodes with small and allocate more load shedding amounts during the load shedding process.

[0177] When scoring each alternative load node according to its equivalent estimated inertia, when load shedding is performed on the alternative load node with a large equivalent estimated inertia, the frequency recovery speed of the node is faster and the lowest point of the frequency drop is higher. Therefore, lower scores can be assigned to the nodes with a large equivalent estimated inertia, and more load shedding amounts can be allocated during the load shedding process.

[0178] When scoring each alternative load node according to the cost per unit load shedding of the alternative load node, the cost per unit load shedding of the distribution lines connected to each alternative load node is evaluated. Nodes with lower costs are assigned lower scores, and more load shedding can be considered during load shedding to reduce economic losses.

[0179] When scoring each alternative load node according to the average load rate of the alternative load node, the ratio of the actual operating load capacity of the distribution lines connected to the alternative load node to the rated capacity of the lines is obtained from the operating data of the power system dispatching platform to get the average load rate of the alternative load node. For load lines with a low average load rate, lower scores can be assigned, and more load shedding can be considered during load shedding.

[0180] Furthermore, for each alternative load node, the scores obtained by scoring the alternative load node according to the importance, voltage sensitivity, equivalent estimated inertia, cost per unit load shedding, and average load rate of the alternative load node are normalized:

[0181]

[0182] where x k is the k-th influencing factor, k = 1, 2, 3, 4, 5; each influencing factor includes the importance, voltage sensitivity, equivalent estimated inertia, cost per unit load shedding, and average load rate of the alternative load node; is the score corresponding to the k-th factor after normalization; x max is the maximum value in the k-th influencing factor, and x min is the minimum value in the k-th influencing factor.

[0183] Furthermore, calculate the comprehensive score of the alternative load node. For any alternative load node Z (Z = 1, 2, …, n; n is the total number of alternative load nodes) in the power system, its comprehensive score is:

[0184]

[0185] where Y Z is the comprehensive score of the alternative load node, , , , , are the normalized values of the scores of the alternative load node Z in the dimensions of importance, voltage sensitivity, equivalent estimated inertia, cost per unit load shedding, and average load rate; , , , , Let \(w_{Z}\), \(S_{Z}\), \(J_{Z}\), \(C_{Z}\), and \(L_{Z}\) be the weight coefficients of the importance, voltage sensitivity, equivalent estimated inertia, cost per unit load shedding, and average load rate of the alternative load node \(Z\), respectively. Each weight coefficient can be determined by the Analytic Hierarchy Process (AHP).

[0186] S602. According to the principle that the lower the comprehensive score of each alternative load node, the more load shedding is allocated, and based on the actual power deficit before round-by-round load shedding and the preset load shedding amount before load shedding, perform round-by-round load shedding on each alternative load node in the power system.

[0187] Exemplarily, according to the principle that the lower the comprehensive score of each alternative load node, the more load shedding is allocated, a genetic algorithm can be used to determine the load shedding amount allocated to each alternative load node.

[0188] Step 1: An objective function can be established as follows:

[0189]

[0190] where \(Z\) max is the objective function, and \(P\) Z.i is the load shedding amount allocated to the alternative load node \(Z\) in each round.

[0191] The objective function needs to satisfy the following constraints:

[0192]

[0193] where \(P\) def.i is the actual power deficit before the \(i\)-th round of load shedding, \(r\) is the total number of rounds of load shedding, \(P\) min.Z is the minimum value of the load shedding amount that the alternative load node \(Z\) can shed, and \(P\) max.Z is the maximum value of the load shedding amount that the alternative load node \(Z\) can shed.

[0194] Step 2: Initialize the population. Randomly generate the initial population. Each individual represents a load shedding allocation scheme, and the load shedding amounts of the alternative load nodes are randomly initialized within their allowed minimum and maximum values.

[0195] Step 3: Determine the fitness function. The fitness function is calculated based on the objective function. The goal is to enable alternative load nodes with lower comprehensive scores to obtain more load shedding amounts.

[0196] Step 4: Selection operation. Use roulette wheel selection to select parent individuals. The higher the fitness, the greater the probability of being selected.

[0197] Step 5: Crossover operation. Use single-point crossover to generate two offspring individuals. The crossover point is randomly selected, and a part of the parent is exchanged with the offspring to ensure that the total load shedding amount of the offspring is still the target value.

[0198] Step 6, Mutation operation. Each individual has a certain probability of slightly changing the load shedding amount of a certain node, and then making the total load shedding amount remain the target value through a scaling factor.

[0199] Step 7, Update the population. Combine the parent generation and the offspring generation, and select the optimal individuals according to the fitness as the next generation.

[0200] Step 8, Output the result. Terminate the algorithm when the number of iterations is reached, and output the optimal load shedding amount allocation scheme.

[0201] Furthermore, when the load shedding amounts allocated to each alternative load node are determined, the alternative load nodes are shed according to the magnitude relationship between the actual power deficit before each round of load shedding and the preset load shedding amount before each round of load shedding.

[0202] For example, if the actual power deficit before a round of load shedding is greater than or equal to the preset load shedding amount before the round of load shedding, the alternative load nodes are shed according to the preset load shedding amount before the round of load shedding. If the actual power deficit before a round of load shedding is less than the preset load shedding amount before the round of load shedding, the alternative load nodes are shed according to the actual power deficit.

[0203] In the embodiments of the present application, by establishing a load shedding evaluation fitness index for alternative load nodes participating in load shedding and using a genetic algorithm to optimize the allocation amount of the load shedding amount for each round of load shedding among alternative load nodes, the secondary disturbance brought to the power system by low-frequency load shedding is reduced, the loss caused by load shedding is also reduced, and the economy of power system safety control is improved.

[0204] In some alternative implementation manners, refer to Figure 8 , Figure 8 which provides a flow schematic diagram of another power system load shedding method, specifically including the following steps:

[0205] S801, Obtain the system operation state of the power system during the target time period.

[0206] S802, According to the system operation state, obtain the sample data of the observation nodes from the historical operation data of the power system.

[0207] S803, According to the preset interference frequency, screen out the target sample data of a single interference event from the sample data of each observation node.

[0208] S804, Fit the frequency sample data in the target sample data of each observation node to obtain the frequency change rate of each observation node at the moment when a single interference event occurs.

[0209] S805. Determine the equivalent estimated inertia of each observation node at the occurrence time of a single disturbance event according to the frequency change rate and power change rate of each observation node at the occurrence time of the single disturbance event.

[0210] S806. Take the average value of the equivalent estimated inertia of each observation node at the occurrence times of a preset number of single disturbance events as the equivalent estimated inertia of each observation node in the target period.

[0211] S807. For each observation node, multiply the equivalent estimated inertia of the observation node in the target period by the operating installed capacity of various types of generator sets of the observation node in the target period.

[0212] S808. Take the ratio of the sum of the products corresponding to each observation node to the operating installed capacity of various types of generator sets in the power system as the equivalent estimated inertia of the power system in the target period.

[0213] S809. Determine the actual power deficit before each round of load shedding according to the equivalent estimated inertia, the rated frequency of the power system, and the frequency change rate before and after each round of load shedding.

[0214] S810. Shed load on the alternative load nodes according to the magnitude relationship between the actual power deficit before each round of load shedding and the preset load shedding amount before each round of load shedding.

[0215] For the specific processes of the above S801 to S810, reference can be made to the descriptions of the method embodiments above. Their implementation principles and technical effects are similar and will not be elaborated here.

[0216] Moreover, the execution order between the above steps is only an exemplary illustration and is not used to limit the execution steps. Other execution orders are within the protection scope of the embodiments of this application.

[0217] It should be understood that although the steps in the flowcharts involved in the above-mentioned embodiments are shown in sequence according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless there is a clear description in this article, there is no strict order restriction for the execution of these steps, and these steps can be executed in other orders. Moreover, at least a part of the steps in the flowcharts involved in the above-mentioned embodiments may include multiple steps or multiple stages. These steps or stages are not necessarily executed at the same moment, but can be executed at different moments. The execution order of these steps or stages is not necessarily sequential, but can be executed alternately or in turn with at least a part of other steps or steps or stages in other steps.

[0218] Based on the same inventive concept, an embodiment of the present application further provides a power system load shedding device for implementing the power system load shedding method involved above. The solution provided by this device for solving problems is similar to the solution recorded in the above method. Therefore, the specific limitations in one or more embodiments of the power system load shedding device provided below can refer to the limitations on the power system load shedding method in the above text, and will not be elaborated here.

[0219] In an exemplary embodiment, as Figure 9 shown, a power system load shedding device is provided, including:

[0220] A first acquisition module 10, configured to acquire the system operation state of the power system during a target period; wherein, the system operation state at least includes the operating installed capacity of various generator sets in the power system and the system load;

[0221] A second acquisition module 20, configured to acquire the sample data of the observation nodes from the historical operation data of the power system according to the system operation state; wherein, the sample data is the historical operation data corresponding to the historical period with the same system operation state as that during the target period;

[0222] A determination module 30, configured to determine the equivalent estimated inertia of the power system during the target period according to the sample data of the observation nodes, the operating installed capacity of various generator sets observed by the observation nodes during the target period, and the operating installed capacity of various generator sets in the power system;

[0223] A load shedding module 40, configured to perform multiple rounds of load shedding on the power system according to the equivalent estimated inertia, the rated frequency of the power system, the frequency change rate before and after load shedding, and the preset load shedding amount before load shedding.

[0224] In the above solution, first, according to the sample data of the observation nodes, the operating installed capacity of various generator sets observed by the observation nodes during the target period, and the operating installed capacity of various generator sets in the power system, the equivalent estimated inertia of the power system during the target period is determined, so that the determined equivalent estimated inertia of the power system during the target period is relatively reliable; then, according to the equivalent estimated inertia, the rated frequency of the power system, the frequency change rate before and after each round of load shedding, and the preset load shedding amount before load shedding, multiple rounds of load shedding are performed on the power system, so that the load shedding amount determined for the power system in each round is more accurate, thereby making the power system more stable.

[0225] In one of the embodiments, there are at least two observation nodes, and the determination module 30 specifically includes:

[0226] A first determination unit, configured to determine the equivalent estimated inertia of each observation node during the target period according to the sample data of each observation node;

[0227] A second determination unit, configured to, for each observation node, determine a product of an equivalent estimated inertia of the observation node in a target period and operating installed capacities of various generator sets observed by the observation node in the target period as an intermediate value;

[0228] A third determination unit, configured to use a ratio of a sum of intermediate values corresponding to each observation node to operating installed capacities of various generator sets in a power system as an equivalent estimated inertia of the power system in the target period.

[0229] In one embodiment, the first determination unit is specifically configured to:

[0230] For each observation node, according to a preset interference frequency, screen out target sample data of a single interference event from sample data of the observation node; fit frequency sample data in the target sample data of the observation node to obtain a frequency change rate of the observation node at the occurrence moment of the single interference event; determine an equivalent estimated inertia of the observation node at the occurrence moment of the single interference event according to the frequency change rate and a power change rate of the observation node at the occurrence moment of the single interference event; use an average value of equivalent estimated inertias of the observation node at the occurrence moments of a preset number of single interference events as an equivalent estimated inertia of the observation node in the target period.

[0231] In one embodiment, the load shedding module 40 is specifically configured to:

[0232] For each round, determine a first ratio of an equivalent estimated inertia corresponding to the round to a rated frequency of the power system; use a product of the first ratio and a frequency change rate before load shedding in the round as an actual power deficit before load shedding in the round; wherein, the equivalent estimated inertia of the first round is an equivalent estimated inertia of the power system in the target period, and the equivalent estimated inertia of each subsequent round is determined according to a load shedding amount of the previous round, the rated frequency of the power system, and frequency change rates before and after load shedding in each round; the load shedding amount of the previous round is determined according to the actual power deficit before and after load shedding in the previous round; perform load shedding on the power system in the round according to the actual power deficit before load shedding in the round and a preset load shedding amount before load shedding in the round.

[0233] In one embodiment, the load shedding module 40 specifically includes:

[0234] A first load shedding unit, configured to, if the actual power deficit before load shedding in the round is greater than or equal to the preset load shedding amount before load shedding in the round, perform load shedding on the power system according to the preset load shedding amount before load shedding in the round;

[0235] A second load shedding unit, configured to, if the actual power deficit before load shedding in the round is less than the preset load shedding amount before load shedding in the round, perform load shedding on the power system according to the actual power deficit.

[0236] In one embodiment, the power system includes alternative load nodes for load shedding. The load shedding module 40 is specifically configured to:

[0237] Score each alternative load node according to its importance, voltage sensitivity, equivalent estimated inertia, unit load shedding cost, and average load rate to obtain the comprehensive score of each alternative load node. According to the principle that the lower the comprehensive score of each alternative load node, the more load shedding amount is allocated, perform round-by-round load shedding on each alternative load node in the power system according to the actual power deficit before round-by-round load shedding and the preset load shedding amount before load shedding.

[0238] Each module in the above power system load shedding device can be implemented in whole or in part by software, hardware, and their combination. The above modules can be embedded in the processor of the computer device in hardware form or independent of it, or stored in the memory of the computer device in software form, so that the processor can call and execute the operations corresponding to the above modules.

[0239] In an exemplary embodiment, a computer device is provided. The computer device can be a server, and its internal structure diagram can be as Figure 10 shown. The computer device includes a processor, a memory, an input / output (I / O) interface, and a communication interface. Among them, the processor, the memory, and the input / output interface are connected through a system bus, and the communication interface is connected to the system bus through the input / output interface. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program, and a database. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The database of the computer device is used to store the operation data of the power system. The input / output interface of the computer device is used to exchange information between the processor and external devices. The communication interface of the computer device is used to communicate with external terminals through a network connection. When the computer program is executed by the processor, it implements a power system load shedding method.

[0240] Those skilled in the art can understand that Figure 10 the structure shown in

[0241] In an exemplary embodiment, a computer device is provided, including a memory and a processor. A computer program is stored in the memory, and when the processor executes the computer program, the steps of the power system load shedding method described in any of the above embodiments are implemented.

[0242] In an embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the steps of the power system load shedding method described in any of the above embodiments are implemented.

[0243] In an embodiment, a computer program product is provided, including a computer program. When the computer program is executed by a processor, the steps of the power system load shedding method described in any of the above embodiments are implemented.

[0244] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use, and processing of relevant data need to comply with relevant regulations.

[0245] Those of ordinary skill in the art can understand that all or part of the processes in the methods of the above embodiments can be completed by instructing relevant hardware through a computer program. The computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above methods. Among them, any reference to a memory, database, or other medium used in the embodiments provided in this application can include at least one of non-volatile memory and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetoresistive random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM), etc. The databases involved in the embodiments provided in this application can include at least one of relational databases and non-relational databases. Non-relational databases can include distributed databases based on blockchain, etc., without limitation. The processors involved in the embodiments provided in this application can be general-purpose processors, central processors, graphics processors, digital signal processors, programmable logic devices, data processing logics based on quantum computing, artificial intelligence (AI) processors, etc., without limitation.

[0246] The technical features of the above embodiments can be combined arbitrarily. For the sake of concise description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered to be within the scope recorded in this application.

[0247] The above-described embodiments merely represent several implementation manners of the present application. The description thereof is relatively specific and detailed, but it should not be construed as a limitation on the patent scope of the present application. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several modifications and improvements can still be made, and these all fall within the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the appended claims.

Claims

1. A method for reducing load in a power system, characterized in that: The method comprises: Acquire the system operation status of the power system in the target period; wherein the system operation status at least includes the operating installed capacity and system load of various types of generator sets in the power system; According to the system operation state, sample data of the observation node is obtained from the historical operation data of the power system; wherein the sample data is the historical operation data corresponding to the historical period that is the same as the system operation state of the target period; Determine the equivalent estimated inertia of the power system during the target period according to the sample data of the observation node, the operating installed capacity of each type of generator set observed by the observation node during the target period, and the operating installed capacity of each type of generator set in the power system; The power system is subjected to multiple rounds of load shedding according to the equivalent estimated inertia, the rated frequency of the power system, the frequency change rate before and after load shedding, and the preset load shedding amount before load shedding.

2. The method according to claim 1, characterized in that There are at least two observation nodes, and determining the equivalent estimated inertia of the power system in the target period according to sample data of the observation nodes, the operating installed capacity of various types of generator sets observed by the observation nodes in the target period, and the operating installed capacity of various types of generator sets in the power system includes: Determine the equivalent estimated inertia of each observation node in the target period according to the sample data of each observation node; For each observation node, the product of the equivalent estimated inertia of the observation node in the target period and the operating installed capacity of various types of generator sets observed by the observation node in the target period is taken as an intermediate value; The sum of the intermediate values ​​corresponding to the observation nodes and the ratio of the operating installed capacity of each type of generator set in the power system are used as the equivalent estimated inertia of the power system in the target period.

3. The method according to claim 2, characterized in that The step of determining the equivalent estimated inertia of each observation node in the target period according to the sample data of each observation node includes: For each observation node, according to a preset interference frequency, target sample data of a single interference event is filtered out from the sample data of the observation node; Fitting the frequency sample data in the target sample data to obtain the frequency change rate of the observation node at the time when a single interference event occurs; Determining the equivalent estimated inertia of the observation node at the time when the single interference event occurs according to the frequency change rate and the power change rate of the observation node at the time when the single interference event occurs; The average value of the equivalent estimated inertia of the observation node at the time when a preset number of single interference events occur is used as the equivalent estimated inertia of the observation node in the target time period.

4. The method according to claim 1, characterized in that: The method of performing multiple rounds of load shedding on the power system according to the equivalent estimated inertia, the rated frequency of the power system, the frequency change rate before and after load shedding, and the preset load shedding amount before load shedding comprises: For each round, determining a first ratio of an equivalent estimated inertia corresponding to the round to a rated frequency of the power system; The product of the first ratio and the frequency change rate before the round of load shedding is used as the actual power shortage before the round of load shedding; wherein the equivalent estimated inertia of the first round is the equivalent estimated inertia of the power system in the target period, and the equivalent estimated inertia of each remaining round is determined according to the load shedding amount of the previous round, the rated frequency of the power system and the frequency change rate before and after each round of load shedding; the load shedding amount of the previous round is determined according to the actual power shortage before and after the previous round of load shedding; The round of load shedding is performed on the power system according to the actual power deficit before the round of load shedding and the preset load shedding amount before the round of load shedding.

5. The method according to claim 4, characterized in that The performing the round of load shedding on the power system according to the actual power shortage before the round of load shedding and the preset load shedding amount before the load shedding comprises: If the actual power deficit before the round of load shedding is greater than or equal to the preset load shedding amount before the round of load shedding, the power system is loaded down according to the preset load shedding amount before the round of load shedding; If the actual power deficit before the round of load shedding is less than the preset load shedding amount before the round of load shedding, the power system is loaded down according to the actual power deficit.

6. The method according to claim 4, characterized in that The power system includes candidate load nodes for load shedding, and the round of load shedding for the power system is performed according to the actual power shortage before the round of load shedding and the preset load shedding amount before the load shedding, including: According to the importance, voltage sensitivity, equivalent estimated inertia, unit load reduction cost and average load rate of each candidate load node, each candidate load node is scored to obtain a comprehensive score of each candidate load node; According to the principle that the lower the comprehensive score of each alternative load node, the more load reduction is allocated, the round of load reduction is performed on each alternative load node in the power system according to the actual power shortage before the round of load reduction and the preset load reduction before load reduction.

7. A load shedding device for a power system, characterized in that: The device comprises: A first acquisition module is used to acquire the system operation status of the power system in the target period; wherein the system operation status at least includes the operating installed capacity and system load of various types of generator sets in the power system; A second acquisition module is used to acquire sample data of the observation node from the historical operation data of the power system according to the system operation state; wherein the sample data is the historical operation data corresponding to the historical period that is the same as the system operation state of the target period; A determination module, configured to determine the equivalent estimated inertia of the power system during the target period according to the sample data of the observation node, the operating installed capacity of each type of generator set observed by the observation node during the target period, and the operating installed capacity of each type of generator set in the power system; The load shedding module is used to perform multiple rounds of load shedding on the power system according to the equivalent estimated inertia, the rated frequency of the power system, the frequency change rate before and after the load shedding, and the preset load shedding amount before the load shedding.

8. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 6 are implemented.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 6 are implemented.

10. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 6 are implemented.

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