Method and system for optimizing stability margin of packet delivery channel based on direct current transmission line

Abstract

The invention discloses a stability margin optimization method and system based on a grouping delivery channel of a direct-current power transmission line, and relates to the technical field of direct-current power transmission and stability judgment. Comprising the steps of collecting outgoing power data of each group of direct-current transmission lines; establishing a time sequence for the collected outgoing power data and carrying out normalization processing; establishing a prediction model and calculating a stability margin index of the delivery channel; and the transmission power is dynamically adjusted based on the stability margin index predicted value, and the stability of the transmission line is optimized. According to the invention, by establishing the outgoing power time sequence and carrying out normalization processing, standardized analysis of various types of generated power data is realized; by establishing a prediction model and introducing influence factors, the stability margin index of the direct-current transmission line at the next moment is accurately predicted, and potential stability risks are identified in advance; a dynamic adjustment strategy is implemented based on a stability margin index prediction value, reasonable power distribution is performed among power transmission lines with different stability margins, and the power transmission fault risk is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of direct current transmission and stability determination, and in particular to a method and system for optimizing stability margin of direct current transmission line grouping transmission channels. Background Art

[0002] With the acceleration of economic development and urbanization, the demand for electricity is increasing. However, the distribution of energy resources and power load centers in various regions of the world is often uneven. Renewable energy resources are usually located in remote areas or areas with abundant energy but sparse populations, while power load centers are mostly concentrated in economically developed and densely populated areas. In order to effectively utilize these dispersed energy resources, they need to be transmitted from the power generation site to the load center far away from the energy production site, and long-distance transmission technology has therefore come into being.

[0003] In traditional AC transmission, long-distance power transmission is susceptible to frequency stability and synchronization issues, especially when a power grid failure occurs, which may trigger a chain reaction and cause a large-scale power outage. DC transmission has higher controllability and has been widely used in long-distance and large-capacity power transmission. It can quickly adjust power, alleviate fault propagation, and play a stabilizing role when an abnormality occurs in the power grid.

[0004] Stability margin refers to the "margin" or "buffer space" that the power system can maintain in a stable state when it is operating normally or being disturbed (such as load fluctuations, faults, etc.). It indicates the system's ability to withstand disturbances or the tolerable disturbance size in the current state. Stability margin is an important indicator to measure the safety margin and anti-disturbance of the power system to maintain stability under various working conditions. For this reason, it is particularly important to study a stability margin that predicts the next moment for DC transmission lines. Summary of the invention

[0005] In view of the problems existing in the prior art, the present invention is proposed.

[0006] Therefore, the problem to be solved by the present invention is how to determine the stability of a DC transmission line by collecting the output of each branch of the DC transmission line group and the stability margin of each branch in real time, and then deriving the stability margin of each group, calculating the total stability margin index of the DC transmission line, and predicting the stability margin index of the DC transmission line at the next moment.

[0007] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0008] In a first aspect, an embodiment of the present invention provides a method for optimizing stability margin of transmission channels based on grouping of DC transmission lines, which includes collecting transmission power data of each group of DC transmission lines;

[0009] Establish a time series for the collected external power data and perform normalization processing;

[0010] Establish a prediction model and calculate the stability margin index of the transmission channel;

[0011] The transmission power is dynamically adjusted based on the predicted value of the stability margin index to optimize the stability of the transmission line.

[0012] As a preferred solution of the method for optimizing the stability margin of the DC power transmission line group transmission channel according to the present invention, the transmission power data includes:

[0013] Grouping data of DC transmission lines, including the number of transmission line groups and the number of branches in each group;

[0014] Power transmission data of each branch, including photovoltaic power generation, wind power generation, hydropower generation, coal power generation and other forms of energy power generation;

[0015] The maximum power carrying capacity data of each branch, including the maximum power carrying capacity limit of each type of energy generation.

[0016] As a preferred solution of the method for optimizing the stability margin of a DC power transmission line group transmission channel according to the present invention, the establishment of a time sequence includes:

[0017] Collect various types of power generation data at fixed time intervals;

[0018] Establish a time series data set of different types of power generation in each branch;

[0019] Record the maximum and minimum values ​​of each type of power generation within a fixed time interval.

[0020] As a preferred solution of the method for optimizing the stability margin of a DC power transmission line group transmission channel according to the present invention, the establishment of a prediction model includes:

[0021] Normalize and preprocess time series data;

[0022] Calculate the influencing factor matrix of power generation data;

[0023] Establish the next moment power prediction model based on the impact factor and normalized data;

[0024] The prediction model is used to calculate the power data of various types of power generation at the next moment.

[0025] As a preferred solution of the method for optimizing the stability margin of a DC power transmission line group transmission channel according to the present invention, the dynamic adjustment includes:

[0026] Calculate the stability margin index of the outbound channel at the current moment and the next moment;

[0027] Determine the transmission power adjustment plan based on the stability margin index;

[0028] Power is adjusted between transmission lines with different stability margins according to preset adjustment thresholds and ratios;

[0029] Realize the optimal distribution of power of each group of transmission lines.

[0030] As a preferred solution of the method for optimizing the stability margin of transmission channels based on grouping of DC transmission lines according to the present invention, the specific calculation of the stability margin index and the prediction model of the transmission channel includes:

[0031] Stability margin index calculation formula:

[0032]

[0033] Where n is the total number of DC transmission line groups, m is the total number of transmission lines in the ath group;

[0034] t 1 ,t 2 ,t 3 ,...,t i ,...,t p is a fixed time interval, p is a natural number; is the photovoltaic power transmitted by the bth transmission line of the ath group at time i, S (a,b),max t 1 ,t 2 ,t 3 ,...,t i ,...,t p , the maximum photovoltaic power generation capacity of the bth transmission line in the ath group at p fixed moments; is the wind power generation power transmitted by the bth transmission line of the ath group at time i, W (a,b),max t 1 ,t 2 ,t 3 ,...,t i ,...,t p , the maximum wind power generation capacity of the bth transmission line in the ath group at p fixed moments; is the hydroelectric power transmitted by the bth transmission line of the ath group at time i, H (a,b),max t 1 ,t 2 ,t 3 ,...,t i ,...,t p, the maximum hydropower generation capacity carried by the bth transmission line in the ath group at p fixed moments; is the coal-fired power transmitted by the bth transmission line of the ath group at time i, F (a,b),max t 1 ,t 2 ,t 3 ,...,t i ,...,t p , the maximum coal-fired power generation capacity of the bth transmission line in the ath group at p fixed moments; is the power generation of other forms of energy transmitted by the bth transmission line of the ath group at time i, p (a,b),max t 1 ,t 2 ,t 3 ,...,t i ,...,t p , the maximum power generation of other forms of energy carried by the b-th transmission line in the a-th group at p fixed moments;

[0035] Normalization formula:

[0036]

[0037] in, is the normalized value of the photovoltaic power transmitted by the bth transmission line of the ath group at time i; is the normalized value of wind power transmitted by the bth transmission line of the ath group at time i;

[0038] is the normalized value of the hydroelectric power transmitted by the bth transmission line in the ath group at time i; is the normalized value of the coal-fired power transmitted by the b-th transmission line of the a-th group at time i; is the normalized value of other forms of energy power transmitted by the bth transmission line of the ath group at time i, S (a,b),min t 1 ,t 2 ,t 3 ,...,t i ,...,t p , the minimum value of photovoltaic power transmitted by the bth transmission line in the ath group at p fixed moments; W (a,b),min t 1 ,t 2 ,t 3 ,...,t i ,...,t p , the minimum wind power generation power transmitted by the bth transmission line in the ath group at p fixed moments; H (a,b),min t 1 ,t2 ,t 3 ,...,t i ,...,t p , the minimum value of hydropower generation power transmitted by the bth transmission line of the ath group at p fixed moments; F (a,b),min t 1 ,t 2 ,t 3 ,...,t i ,...,t p , the minimum value of coal power generation transmitted by the bth transmission line of the ath group at p fixed moments; p (a,b),min t 1 ,t 2 ,t 3 ,...,t i ,...,t p , the minimum value of other forms of energy power transmitted by the bth transmission line in the ath group at p fixed moments;

[0039] Impact factor calculation formula:

[0040]

[0041] Prediction model formula:

[0042]

[0043] in, The photovoltaic power t transmitted by the bth transmission line of the ath group p+1 The predicted value of the normalized value at the moment; The wind power generation power t transmitted by the bth transmission line of the ath group p+1 The predicted value of the normalized value at the moment; The hydroelectric power t transmitted by the bth transmission line of the ath group p+1 The predicted value of the normalized value at the moment; The coal-fired power t transmitted by the bth transmission line of the ath group p+1 The predicted value of the normalized value at the moment; Power generation of other forms of energy transmitted by the bth transmission line of group a t p+1 The predicted value of the normalized value at time instant,

[0044] is the predicted value matrix of the normalized value of the power data transmitted outside the DC transmission line at the moment;

[0045]

[0046] The power data transmitted outside the DC transmission line at t 1 ,t 2,t 3 ,...,t i ,...,t p , the normalized data matrix calculated at p fixed time intervals; is the impact factor matrix.

[0047] As a preferred solution of the method for optimizing the stability margin of the DC power transmission line group transmission channel according to the present invention, the specific strategy of the dynamic adjustment is:

[0048] When the predicted value of the stability margin is greater than or equal to 0.64, the current transmission power allocation is maintained and the transmission power of each branch remains unchanged;

[0049] When the predicted stability margin value is less than 0.64 and greater than or equal to 0.44, the power of the transmission line with a lower stability margin of 15% is adjusted to the transmission line with a higher stability margin of 15% to ensure the overall transmission stability;

[0050] When the predicted stability margin value is less than 0.44, the power of the transmission line with a lower stability margin of 35% is adjusted to the transmission line with a higher stability margin of 35% to improve the stability performance of the system;

[0051] Through dynamic adjustment strategies, continuous optimization of the stability margin of transmission lines can be achieved.

[0052] In a second aspect, an embodiment of the present invention provides a stability margin optimization system based on a DC transmission line group transmission channel, which includes a transmission power acquisition module, a monitoring module and an optimization and adjustment module;

[0053] The external power collection module is used to collect the grouping data, external power data and maximum carrying power data of each group of DC transmission lines, establish a time series and perform normalization processing;

[0054] The monitoring module is used to establish a prediction model, calculate the influencing factors, and predict the stability margin index of the DC transmission line at the next moment;

[0055] The optimization and adjustment module is used to dynamically adjust the transmission power according to the predicted value of the stability margin index to optimize the stability of the transmission line.

[0056] In a third aspect, an embodiment of the present invention provides a computer device, including a memory and a processor, wherein the memory stores a computer program, wherein: when the computer program instructions are executed by the processor, the steps of the method for optimizing the stability margin of a grouped transmission channel based on a DC transmission line as described in the first aspect of the present invention are implemented.

[0057] In a fourth aspect, an embodiment of the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein: when the computer program instructions are executed by a processor, the steps of the method for optimizing the stability margin of a grouped transmission channel of a DC transmission line based on the first aspect of the present invention are implemented.

[0058] The beneficial effects of the present invention are as follows: the stability margin optimization method based on the grouped transmission channel of the direct current transmission line provided by the present invention realizes the standardized analysis of various types of power generation data by establishing the transmission power time series and performing normalization processing, thereby improving the accuracy and reliability of data processing; by establishing a prediction model and introducing influencing factors, the stability margin index of the direct current transmission line at the next moment is accurately predicted, potential stability risks are identified in advance, and the predictability and controllability of the system are enhanced; a dynamic adjustment strategy is implemented based on the predicted value of the stability margin index, and reasonable power allocation is performed among transmission lines with different stability margins, thereby effectively improving the overall stability performance of the system and reducing the risk of transmission failures. Moreover, the method can realize stability optimization only by collecting transmission power data, does not need to rely on professional experimental instruments, has low implementation cost and strong applicability, and the present invention has achieved remarkable results in terms of system stability, prediction accuracy and implementation cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0060] Figure 1 The figure is a flow chart of the stability margin optimization method based on the grouping transmission channel of DC transmission lines. DETAILED DESCRIPTION

[0061] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0062] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0063] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0064] Example 1

[0065] Reference Figure 1 , which is the first embodiment of the present invention, and provides a method for optimizing the stability margin of a DC transmission line group transmission channel, comprising:

[0066] S1, collecting the external power data of each group of DC transmission lines;

[0067] It should be noted that the external power data is divided into two categories: real-time data and historical operation data. The real-time data includes photovoltaic power, wind power, hydropower, coal power and other forms of energy power of each group of DC transmission lines, which is used to monitor the real-time operation status of each group of lines; the historical operation data includes the maximum carrying power of each type of power generation and historical transmission records, which are used to evaluate the overall transmission capacity of the line. The system uses standard communication protocols to collect these data regularly.

[0068] It should be noted that the system uses a standard communication protocol to collect data every 10 minutes. Each group of DC transmission lines is equipped with a power collection device to record the power data of different types of power generation in real time. For historical operation data, the system will save nearly 30 days of data for analysis and evaluation. The collected data is processed by the data preprocessing module for outlier detection and missing value processing to ensure the integrity and accuracy of the data.

[0069] S2, establishing a time series for the collected external power data and performing normalization processing;

[0070] It should be noted that the time series is established by using a sampling method based on fixed time intervals, which mainly includes the time series recording of different types of power generation data. By recording the maximum and minimum values ​​of each type of power generation within a fixed time interval, the foundation for subsequent normalization processing is laid. The maximum and minimum value normalization method can effectively eliminate the influence of different dimensions.

[0071] It should be noted that the system selects 24 hours as a complete time window and processes the data within this time window as a data set. During normalization, the system automatically updates the maximum and minimum values ​​of each type of power generation to ensure the timeliness of the normalization results. For possible data fluctuations, the system uses a sliding average method for smoothing to improve the stability of the time series.

[0072] S3, establishing a prediction model and calculating the stability margin index of the transmission channel;

[0073] It should be noted that the prediction model is established using a calculation method based on the influence factor matrix. This method determines the influence factors by analyzing the normalized data matrix, and calculates the prediction value at the next moment through the influence factors and the current normalized data. At the same time, the stability margin index calculation is introduced to evaluate the system stability.

[0074] It should be noted that the least squares method is used to calculate the influencing factor matrix, and the weights of each parameter are determined by analyzing the changing trend of historical data. The system will regularly calibrate the influencing factors based on the deviation between the predicted results and the actual values ​​to improve the prediction accuracy. The calculation of the stability margin index takes into account the characteristics of various types of power generation and the carrying capacity of the transmission line, providing a decision-making basis for dynamic adjustment.

[0075] S4, dynamically adjust the transmission power based on the predicted value of the stability margin index to optimize the stability of the transmission line;

[0076] It should be noted that the dynamic adjustment adopts a hierarchical optimization strategy with strong adaptability. This method can automatically select the adjustment ratio according to the predicted value of the stability margin and redistribute the power of the transmission lines with lower stability margins. When the system stability does not meet the requirements, it will be optimized and adjusted through the feedback mechanism.

[0077] Example 2

[0078] Reference Figure 1 , which is the second embodiment of the present invention, and provides a method for optimizing stability margin of a DC transmission line group transmission channel, comprising:

[0079] S1, collecting the external power data of each group of DC transmission lines;

[0080] In the embodiment of the present application, the external power data includes:

[0081] Grouping data of DC transmission lines, including the number of transmission line groups and the number of branches in each group;

[0082] Power transmission data of each branch, including photovoltaic power generation, wind power generation, hydropower generation, coal power generation and other forms of energy power generation;

[0083] The maximum power carrying capacity data of each branch, including the maximum power carrying capacity limit of each type of energy generation.

[0084] S2, establishing a time series for the collected external power data and performing normalization processing;

[0085] In the embodiment of the present application, the establishing time sequence includes:

[0086] Collect various types of power generation data at fixed time intervals;

[0087] Establish a time series data set of different types of power generation in each branch;

[0088] Record the maximum and minimum values ​​of each type of power generation within a fixed time interval.

[0089] It should be noted that the time series establishment process adopts a data recording method with a fixed time interval to organize various types of power generation data into a data matrix according to the order of collection time. The normalization process adopts the maximum and minimum value standardization method to unify different types of power generation data into the same numerical range.

[0090] It should be noted that the system uses 12 hours as a calculation cycle, during which the maximum and minimum values ​​of each type of power generation are recorded. For each type of power generation, the system evaluates the load of the transmission line by calculating its ratio to the maximum load power. At the same time, the system will perform a quality assessment on the normalized data to ensure data consistency.

[0091] Photovoltaic power output S transmitted by DC transmission line (a,b),t1 ,S (a,b),t2 ,...,S (a,b),ti ,...,S (a,b),tp , DC transmission line external wind power generation power W (a,b),t1 ,W (a,b),t2 ,...,W (a,b),ti ,...W (a,b),tp , the power of hydropower transmitted outside the DC transmission line H (a,b),t1 ,H (a,b),t2 ,...,H (a,b),ti ,...,H (a,b),tp , DC transmission line external coal-fired power F (a,b),t1 ,F (a,b),t2 ,...,F (a,b),ti ,...,F (a,b),tp , DC transmission lines transmit other forms of energy generation power

[0092] Create the following time series:

[0093]

[0094] The collected values ​​are normalized according to the following formula:

[0095]

[0096] in, is the normalized value of the photovoltaic power transmitted by the bth transmission line of the ath group at time i; is the normalized value of wind power transmitted by the bth transmission line of the ath group at time i;

[0097] is the normalized value of the hydroelectric power transmitted by the bth transmission line in the ath group at time i; is the normalized value of the coal-fired power transmitted by the b-th transmission line of the a-th group at time i; is the normalized value of other forms of energy power transmitted by the bth transmission line of the ath group at time i, S (a,b),min t 1 ,t 2 ,t 3 ,...,t i ,...,t p , the minimum value of photovoltaic power transmitted by the bth transmission line in the ath group at p fixed moments; W (a,b),min t 1 ,t 2 ,t 3 ,...,t i ,...,t p , the minimum wind power generation power transmitted by the bth transmission line in the ath group at p fixed moments; H (a,b),min t 1 ,t 2 ,t 3 ,...,t i ,...,t p , the minimum value of hydropower generation power transmitted by the bth transmission line of the ath group at p fixed moments; F (a,b),min t 1 ,t 2 ,t 3 ,...,t i ,...,t p , the minimum value of coal power generation transmitted by the bth transmission line of the ath group at p fixed moments; p (a,b),min t 1 ,t 2 ,t 3 ,...,t i ,...,t p , the minimum power generation power of other forms of energy transmitted by the bth transmission line in the ath group at p fixed moments.

[0098] S3, establishing a prediction model and calculating the stability margin index of the transmission channel;

[0099] In the embodiment of the present application, the establishment of the prediction model includes:

[0100] Normalize and preprocess time series data;

[0101] Calculate the influencing factor matrix of power generation data;

[0102] Establish the next moment power prediction model based on the impact factor and normalized data;

[0103] The prediction model is used to calculate the power data of various types of power generation at the next moment.

[0104] It should be noted that the calculation of the stability margin index needs to consider the ratio of all types of power generation of each group and each branch to its maximum carrying power. The prediction model can be used to obtain the predicted value of each type of power generation at the next moment, and then calculate the stability margin index at the next moment.

[0105] It should be noted that the stability margin index of the transmission channel for defining the DC transmission line group is

[0106] Where n is the total number of DC transmission line groups, m is the total number of transmission lines in the ath group;

[0107] t 1 ,t 2 ,t 3 ,...,t i ,...,t p is a fixed time interval, p is a natural number; is the photovoltaic power transmitted by the bth transmission line of the ath group at time i, S (a,b),max t 1 ,t 2 ,t 3 ,...,t i ,...,t p , the maximum photovoltaic power generation capacity of the bth transmission line in the ath group at p fixed moments; is the wind power generation power transmitted by the bth transmission line of the ath group at time i, W (a,b),max t 1 ,t 2 ,t 3 ,...,t i ,...,t p , the maximum wind power generation capacity of the bth transmission line in the ath group at p fixed moments; is the hydroelectric power transmitted by the bth transmission line of the ath group at time i, H (a,b),max t 1 ,t 2 ,t 3 ,...,t i ,...,t p, the maximum hydropower generation capacity carried by the bth transmission line in the ath group at p fixed moments; is the coal-fired power transmitted by the bth transmission line of the ath group at time i, F (a,b),max t 1 ,t 2 ,t 3 ,...,t i ,...,t p , the maximum coal-fired power generation capacity of the bth transmission line in the ath group at p fixed moments; is the power generation of other forms of energy transmitted by the bth transmission line of the ath group at time i, p (a,b),max t 1 ,t 2 ,t 3 ,...,t i ,...,t p , the maximum power generation of other forms of energy carried by the b-th transmission line in the a-th group at p fixed moments;

[0108] Calculate the influencing factors of the DC transmission line external power data at the next moment:

[0109]

[0110] Calculate the predicted value of the normalized value of the DC transmission line external power data at the next moment:

[0111]

[0112] in, The photovoltaic power t transmitted by the bth transmission line of the ath group p+1 The predicted value of the normalized value at the moment; The wind power generation power t transmitted by the bth transmission line of the ath group p+1 The predicted value of the normalized value at the moment; The hydroelectric power t transmitted by the bth transmission line of the ath group p+1 The predicted value of the normalized value at the moment; The coal-fired power t transmitted by the bth transmission line of the ath group p+1 The predicted value of the normalized value at the moment; Power generation of other forms of energy transmitted by the bth transmission line of group a t p+1 The predicted value of the normalized value at time instant,

[0113] is the predicted value matrix of the normalized value of the power data transmitted outside the DC transmission line at the moment;

[0114]

[0115] The power data transmitted outside the DC transmission line at t 1 ,t 2 ,t 3 ,...,t i ,...,t p , the normalized data matrix calculated at p fixed time intervals; is the impact factor matrix.

[0116] S4, dynamically adjust the transmission power based on the predicted value of the stability margin index to optimize the stability of the transmission line;

[0117] In the embodiment of the present application, the dynamic adjustment includes:

[0118] Calculate the stability margin index of the outbound channel at the current moment and the next moment;

[0119] Determine the transmission power adjustment plan based on the stability margin index;

[0120] Power is adjusted between transmission lines with different stability margins according to preset adjustment thresholds and ratios;

[0121] Realize the optimal distribution of power of each group of transmission lines.

[0122] It should be noted that the system sets three stability margin thresholds as the basis for adjustment: when the stability margin prediction value is ≥ 0.64, the current power allocation is maintained; when the prediction value is in the interval [0.44, 0.64), a 15% power adjustment is made; when the prediction value is < 0.44, a 35% power adjustment is made;

[0123] Calculate the predicted value of the stability margin index of the transmission channel of the DC transmission line group at the next moment

[0124]

[0125] If the predicted value of the stability margin index of the transmission channel of the DC transmission line group at the next moment is greater than or equal to 0.64, it means that the stability margin of each group of DC transmission point lines meets the transmission stability requirements and there is no need to adjust the transmission power of each branch. If the predicted value of the stability margin is less than 0.64 and greater than or equal to 0.44, the stability margin does not meet the DC transmission stability requirements, and the power borne by the 15% lower stability margin transmission line needs to be adjusted to the 15% higher stability margin transmission line. If the predicted value of the stability margin is less than 0.44, the power borne by the 35% lower stability margin transmission line needs to be adjusted to the 35% higher stability margin transmission line.

[0126] It should be noted that the power adjustment process is to transfer the power of the transmission line with lower stability margin to the transmission line with higher stability margin. The adjustment ratios are 15% and 35% respectively. This hierarchical adjustment strategy can take corresponding optimization measures according to the different degrees of system stability.

[0127] Furthermore, this embodiment also provides a stability margin optimization system based on direct current transmission line grouping transmission channel, including a transmission power acquisition module, a monitoring module and an optimization and adjustment module;

[0128] The external power collection module is used to collect the grouping data, external power data and maximum carrying power data of each group of DC transmission lines, establish a time series and perform normalization processing;

[0129] The monitoring module is used to establish a prediction model, calculate the influencing factors, and predict the stability margin index of the DC transmission line at the next moment;

[0130] The optimization and adjustment module is used to dynamically adjust the transmission power according to the predicted value of the stability margin index to optimize the stability of the transmission line.

[0131] This embodiment also provides a computer device, which is applicable to the case of a method for optimizing the stability margin of a DC transmission line group transmission channel, and includes a memory and a processor; the memory is used to store computer executable instructions, and the processor is used to execute the computer executable instructions to implement the method for optimizing the stability margin of a DC transmission line group transmission channel proposed in the above embodiment.

[0132] The computer device may be a terminal, and the computer device includes a processor, a memory, a communication interface, a display screen and an input device connected via a system bus. 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 and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The communication interface of the computer device is used to communicate with an external terminal in a wired or wireless manner, and the wireless manner can be achieved through WIFI, an operator network, NFC (near field communication) or other technologies. The display screen of the computer device may be a liquid crystal display screen or an electronic ink display screen, and the input device of the computer device may be a touch layer covering the display screen, or a key, trackball or touchpad provided on the housing of the computer device, or an external keyboard, touchpad or mouse, etc.

[0133] This embodiment also provides a storage medium on which a computer program is stored. When the program is executed by a processor, the method for optimizing the stability margin of a grouped transmission channel based on a DC transmission line as proposed in the above embodiment is implemented.

[0134] In summary, the stability margin optimization method based on the grouped transmission channel of the DC transmission line provided by the present invention realizes the standardized analysis of various types of power generation data by establishing the transmission power time series and performing normalization processing, thereby improving the accuracy and reliability of data processing; by establishing a prediction model and introducing influencing factors, the stability margin index of the DC transmission line at the next moment is accurately predicted, potential stability risks are identified in advance, and the predictability and controllability of the system are enhanced; a dynamic adjustment strategy is implemented based on the predicted value of the stability margin index, and reasonable power allocation is performed among transmission lines with different stability margins, which effectively improves the overall stability performance of the system and reduces the risk of transmission failures. Moreover, the method can achieve stability optimization only by collecting transmission power data, does not need to rely on professional experimental instruments, has low implementation cost and strong applicability, and the present invention has achieved remarkable results in terms of system stability, prediction accuracy and implementation cost.

[0135] Example 3

[0136] This is the third embodiment of the present invention. This embodiment provides a method for optimizing the stability margin of a DC transmission line group transmission channel. In order to verify the beneficial effects of the present invention, scientific demonstration is carried out through economic benefit calculation and simulation experiments.

[0137] In order to verify the effectiveness of the method of the present invention, a large-capacity inter-provincial DC transmission project was selected as the test object. The project includes three transmission line groups, each with 4, 3 and 3 branches, respectively, for transmitting different types of clean energy electricity. The test was conducted from July 15 to July 21, 2023, and the sampling time interval was set to 30 minutes. The specific implementation process is as follows:

[0138] First, an intelligent data acquisition system was configured, and high-precision power acquisition devices (sampling accuracy ±0.1%) were installed at the key nodes of each group of lines to collect the power generation data of each branch in real time. The acquisition system is connected to the central control room through an optical fiber communication network to ensure the real-time and reliability of data transmission. Each sampling point records the power generation value of photovoltaic, wind, hydropower, coal and other energy sources. At the same time, the system automatically records the maximum load power limit of each branch in different time periods to provide a benchmark for subsequent optimization and adjustment.

[0139] In the data preprocessing stage, a five-point smoothing filter algorithm was used to eliminate sampling noise, and a piecewise linear interpolation method was used to repair a small number of missing data points (missing rate < 0.5%). To improve data quality, an outlier detection threshold of ±3σ was set, and data points out of the range were marked and manually reviewed.

[0140] In the process of establishing the time series, 24 hours was taken as a complete statistical cycle, and a 336×15 time series matrix (7 days×48 sampling points / day×15 power parameters) was established. The improved maximum and minimum value normalization method was used to unify the power data of different energy types into the [0,1] interval to facilitate subsequent modeling and analysis.

[0141] In the prediction model construction process, an adaptive weighted influence factor calculation method is innovatively introduced. By analyzing the power change trend at adjacent time points, the parameters of the influence factor matrix are dynamically adjusted to improve the model's adaptability to power fluctuations. To verify the effectiveness of the method, comparative tests were conducted using the traditional method and the method of the present invention, and the results are shown in the following table:

[0142] Transmission Line Group Test items Traditional methods Method of the present invention Optimization improvement ratio (%) Group A (4 branches) Prediction deviation rate (%) 4.82 2.15 55.39 Group A (4 branches) Stability Margin Index 0.58 0.71 22.41 Group A (4 branches) System adjustment times (times / day) 12 5 58.33 Group B (3 branches) Prediction deviation rate (%) 5.13 2.31 54.97 Group B (3 branches) Stability Margin Index 0.55 0.68 23.64 Group B (3 branches) System adjustment times (times / day) 15 6 60.00 Group C (3 branches) Prediction deviation rate (%) 4.95 2.28 53.94 Group C (3 branches) Stability Margin Index 0.56 0.69 23.21 Group C (3 branches) System adjustment times (times / day) 14 5 64.29

[0143] The following conclusions can be drawn from the analysis of the test data:

[0144] The prediction accuracy is significantly improved: the prediction deviation rate of the method of the present invention is reduced by an average of 54.77% in the three transmission line groups. Specifically, the prediction deviation rate of group A is reduced from 4.82% to 2.15%, group B is reduced from 5.13% to 2.31%, and group C is reduced from 4.95% to 2.28%. This significant improvement is mainly due to the introduction of adaptive weight influence factors, which enables the prediction model to better adapt to the power fluctuation characteristics.

[0145] The system stability is greatly improved: After adopting the method of the present invention, the stability margin index of the three line groups has increased to above 0.68, with an average increase of 23.09%. This shows that the safety margin of system operation has been effectively guaranteed. In particular, in group A, where the proportion of renewable energy power generation is relatively high, the stability margin index has increased to 0.71, the highest among the three groups, which fully demonstrates that the method has outstanding advantages in dealing with renewable energy transmission with large volatility.

[0146] The control efficiency is significantly improved: The method of the present invention significantly reduces the frequency of system adjustments, with an average reduction of 60.87%. The number of daily adjustments in Group A was reduced from 12 to 5, in Group B from 15 to 6, and in Group C from 14 to 5. The reduction in the number of adjustments not only reduces the burden of system operation and maintenance, but also improves the overall stability of the transmission system.

[0147] Significant economic benefits: According to statistics, the reduced number of adjustments and improved prediction accuracy have improved the system's operating efficiency by about 15%, and it is expected that the annual operation and maintenance costs can be saved by more than 2 million yuan. At the same time, the improvement of stability margin also makes it possible to increase the capacity of the system, leaving room for future system expansion.

[0148] These data fully demonstrate the significant advantages of the method of the present invention in practical applications. It not only improves prediction accuracy and system stability, but also reduces operation and maintenance costs, and has important practical value.

[0149] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A method for optimizing stability margin of DC transmission line group transmission channels, characterized in that: include, Collect the external power data of each group of DC transmission lines; Establish a time series for the collected external power data and perform normalization processing; Establish a prediction model and calculate the stability margin index of the transmission channel; The transmission power is dynamically adjusted based on the predicted value of the stability margin index to optimize the stability of the transmission line.

2. The method for optimizing stability margin of DC power transmission line grouping transmission channel according to claim 1, characterized in that: The external power data includes: Grouping data of DC transmission lines, including the number of transmission line groups and the number of branches in each group; Power transmission data of each branch, including photovoltaic power generation, wind power generation, hydropower generation, coal power generation and other forms of energy power generation; The maximum power carrying capacity data of each branch, including the maximum power carrying capacity limit of each type of energy generation.

3. The method for optimizing stability margin of DC transmission line grouping transmission channel according to claim 2, characterized in that: The establishing time sequence comprises: Collect various types of power generation data at fixed time intervals; Establish a time series data set of different types of power generation in each branch; Record the maximum and minimum values ​​of each type of power generation within a fixed time interval.

4. The method for optimizing stability margin of DC transmission line grouping transmission channel according to claim 3, characterized in that: The establishment of the prediction model comprises: Normalize and preprocess time series data; Calculate the influencing factor matrix of power generation data; Establish the next moment power prediction model based on the impact factor and normalized data; The prediction model is used to calculate the power data of various types of power generation at the next moment.

5. The method for optimizing stability margin of DC transmission line grouping transmission channel according to claim 4, characterized in that: The dynamic adjustment includes: Calculate the stability margin index of the outbound channel at the current moment and the next moment; Determine the transmission power adjustment plan based on the stability margin index; Power is adjusted between transmission lines with different stability margins according to preset adjustment thresholds and ratios; Realize the optimal distribution of power of each group of transmission lines.

6. The method for optimizing stability margin of DC transmission line grouping transmission channel according to claim 5, characterized in that: The specific calculation of the transmission channel stability margin index and prediction model includes: Stability margin index calculation formula: Where n is the total number of DC transmission line groups, m is the total number of transmission lines in the ath group; t1,t2,t3,...,t i ,...,t p is a fixed time interval, p is a natural number; is the photovoltaic power transmitted by the bth transmission line of the ath group at time i, S (a,b),max for t1, t2, t3, ..., t i ,...,t p , the maximum photovoltaic power generation capacity of the bth transmission line in the ath group at p fixed moments; is the wind power generation power transmitted by the bth transmission line of the ath group at time i, W (a,b),max for t1, t2, t3, ..., t i ,...,t p , the maximum wind power generation capacity of the bth transmission line in the ath group at p fixed moments; is the hydroelectric power transmitted by the bth transmission line of the ath group at time i, H (a,b),max for t1, t2, t3, ..., t i ,...,t p , the maximum hydropower generation capacity carried by the bth transmission line in the ath group at p fixed moments; is the coal-fired power transmitted by the bth transmission line of the ath group at time i, F (a,b),max for t1, t2, t3, ..., t i ,...,t p , the maximum coal-fired power generation capacity of the bth transmission line in the ath group at p fixed moments; is the power generation of other forms of energy transmitted by the bth transmission line of the ath group at time i, p (a,b),max for t1, t2, t3, ..., t i ,...,t p , the maximum power generation of other forms of energy carried by the b-th transmission line in the a-th group at p fixed moments; Normalization formula: in, is the normalized value of the photovoltaic power transmitted by the bth transmission line of the ath group at time i; is the normalized value of wind power transmitted by the bth transmission line of the ath group at time i; is the normalized value of the hydroelectric power transmitted by the bth transmission line in the ath group at time i; is the normalized value of the coal-fired power transmitted by the b-th transmission line of the a-th group at time i; is the normalized value of other forms of energy power transmitted by the bth transmission line of the ath group at time i, S (a,b),min for t1, t2, t3, ..., t i ,...,t p , the minimum value of photovoltaic power transmitted by the bth transmission line in the ath group at p fixed moments; W (a,b),min for t1, t2, t3, ..., t i ,...,t p , the minimum wind power generation power transmitted by the bth transmission line in the ath group at p fixed moments; H (a,b),min for t1, t2, t3, ..., t i ,...,t p , the minimum value of hydropower generation power transmitted by the bth transmission line of the ath group at p fixed moments; F (a,b),min for t1, t2, t3, ..., t i ,...,t p , the minimum value of coal power generation transmitted by the bth transmission line of the ath group at p fixed moments; p (a,b),min for t1, t2, t3, ..., t i ,...,t p , the minimum value of other forms of energy power transmitted by the bth transmission line in the ath group at p fixed moments; Impact factor calculation formula: Prediction model formula: in, The photovoltaic power t transmitted by the bth transmission line of the ath group p+1 The predicted value of the normalized value at the moment; The wind power generation power t transmitted by the bth transmission line of the ath group p+1 The predicted value of the normalized value at the moment; The hydroelectric power t transmitted by the bth transmission line of the ath group p+1 The predicted value of the normalized value at the moment; The coal-fired power t transmitted by the bth transmission line of the ath group p+1 The predicted value of the normalized value at the moment; Power generation of other forms of energy transmitted by the bth transmission line of group a t p+1 The predicted value of the normalized value at time instant, is the predicted value matrix of the normalized value of the power data transmitted outside the DC transmission line at the moment; The power data transmitted outside the DC transmission line at t1, t2, t3, ..., t i ,...,t p , the normalized data matrix calculated at p fixed time intervals; is the impact factor matrix.

7. The method for optimizing stability margin of DC power transmission line grouping transmission channel according to claim 6, characterized in that: The specific strategy of the dynamic adjustment is: When the predicted value of the stability margin is greater than or equal to 0.64, the current transmission power allocation is maintained and the transmission power of each branch remains unchanged; When the predicted stability margin value is less than 0.64 and greater than or equal to 0.44, the power of the transmission line with a lower stability margin of 15% is adjusted to the transmission line with a higher stability margin of 15% to ensure the overall transmission stability; When the predicted stability margin value is less than 0.44, the power of the transmission line with a lower stability margin of 35% is adjusted to the transmission line with a higher stability margin of 35% to improve the stability performance of the system; Through dynamic adjustment strategies, continuous optimization of the stability margin of transmission lines can be achieved.

8. A system for optimizing stability margin of DC power transmission line group transmission channels, based on the method for optimizing stability margin of DC power transmission line group transmission channels according to any one of claims 1 to 7, characterized in that: It also includes an external power acquisition module, a monitoring module and an optimization and adjustment module; The external power collection module is used to collect the grouping data, external power data and maximum carrying power data of each group of DC transmission lines, establish a time series and perform normalization processing; The monitoring module is used to establish a prediction model, calculate the influencing factors, and predict the stability margin index of the DC transmission line at the next moment; The optimization and adjustment module is used to dynamically adjust the transmission power according to the predicted value of the stability margin index to optimize the stability of the transmission line.

9. 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 for optimizing the stability margin of a DC transmission line group transmission channel according to any one of claims 1 to 7 are implemented.

10. 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 for optimizing the stability margin of a DC power transmission line group transmission channel according to any one of claims 1 to 7 are implemented.

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