Method for evaluating carrying capacity of distributed power supply of power grid
By combining multi-scale spatiotemporal feature extraction and deep learning models with reinforcement learning and distributed computing, the dynamic modeling and topological adaptability problems in the evaluation of distributed power generation capacity in power grids are solved, high-precision, real-time and robust power grid evaluation is achieved, and the utilization rate of new energy and power grid security are improved.
Patent Information
- Application Number
- CN202510742329.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-05
- Publication Date
- 2025-09-09
- Estimated Expiration
- Not applicable · inactive patent
AI Technical Summary
Existing methods for evaluating the carrying capacity of distributed power sources in power grids are unable to effectively capture the randomness and intermittency of distributed power output and the dynamic changes in load demand. They also lack accuracy and robustness under complex power grid topologies, affecting the reliability of power grid planning and operation.
The method adopts multi-scale spatiotemporal feature extraction and fusion, hybrid deep learning model prediction, reinforcement learning optimization, distributed computing and risk quantification. Multi-scale features are extracted through wavelet transform and graph neural network, combined with Transformer and gated recurrent unit models for prediction, embedded in physical constraints, and extreme scenarios are generated through generative adversarial networks for robustness evaluation.
It significantly improves the accuracy and adaptability of distributed power generation capacity assessment in power grids, shortens calculation time, enhances the security and stability of power grids in extreme scenarios, and supports more reliable power grid planning and new energy access decisions.
Smart Images

Figure CN120613776A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of power grids, and in particular to a method for evaluating the carrying capacity of distributed power sources in a power grid. Background Art
[0002] With the rapid development of renewable energy, the penetration of distributed power sources, such as photovoltaics and wind power, in the power grid continues to increase, creating an increasingly urgent need to assess the carrying capacity of distributed power sources. However, existing assessment methods are mostly based on static models or single-time-scale analysis, which makes it difficult to effectively capture the randomness and intermittent nature of distributed power output and the dynamic changes in load demand. For example, traditional methods often assume a fixed load or a single operating condition, ignoring multi-scale fluctuations ranging from minutes to days. This results in significant deviations between assessment results and actual operating conditions, impacting the reliability of grid planning and operational decisions.
[0003] Furthermore, existing technologies have significant limitations when dealing with complex grid topologies. Traditional methods often employ simplified topologies or single-node analysis, failing to fully consider spatial dependencies between nodes, such as power flow distribution and voltage correlation. This makes it difficult to adapt to dynamic changes in grid topology, especially in scenarios with a high proportion of distributed generation. This results in inaccurate load-carrying capacity assessment results in complex grids, potentially leading to voltage overshoots and line overloads, limiting the efficient utilization of renewable energy.
[0004] The optimization efficiency and real-time performance of existing assessment methods also struggle to meet the demands of smart grids. Traditional optimization algorithms consume long computational time, struggle to achieve sub-second responses, and are unsuitable for real-time scheduling scenarios. Furthermore, existing methods lack robustness to extreme operating scenarios and lack effective risk quantification mechanisms, making it difficult to ensure the safety and stability of the grid under high-risk conditions. These issues collectively limit the accuracy and practicality of distributed generation capacity assessments. Summary of the Invention
[0005] The present invention aims to provide a new method for evaluating the carrying capacity of distributed power sources in a power grid, which can comprehensively consider multi-scale dynamic characteristics, complex topology, real-time optimization and robustness.
[0006] To achieve the above objectives, the present invention proposes the following technical solution: a method for evaluating the carrying capacity of distributed power sources in a power grid, the method comprising the following steps: Step 1: Multi-scale spatiotemporal feature extraction and fusion. Real-time grid operation data is collected, including distributed power generation output, load demand, voltage, current, and power flow. The distributed power generation output and load data are decomposed at multiple scales using wavelet transform to extract multi-scale temporal features at the minute, hour, and day levels. The grid topology is modeled using a graph neural network to extract spatial dependency features between nodes, including power flow distribution and voltage correlation. A multi-head attention mechanism is used to fuse temporal and spatial features to generate a comprehensive feature vector. Step 2: Hybrid deep learning model prediction and physical constraint embedding. Based on the comprehensive feature vector, a hybrid Transformer and gated recurrent unit model is constructed to predict the distributed power generation capacity of each node in the power grid. The Transformer module captures long-term dependencies, and the gated recurrent unit module processes short-term sequence features. Grid physical constraints, including power balance constraints and voltage stability constraints, are embedded in the model output layer to ensure that the prediction results conform to the laws of power grid operation. Through an online learning mechanism, model parameters are dynamically updated using real-time data. Step 3: Adaptive optimization based on reinforcement learning uses a deep deterministic policy gradient algorithm, taking the grid operating status as input to optimize the access capacity and location of distributed generation. This multi-objective optimization is achieved by comprehensively considering maximizing access capacity, voltage stability, line load balancing, and minimizing operating costs through a reward function. Step 4: Distributed computing and digital twin verification. Leveraging a distributed computing architecture, feature extraction, model prediction, and optimization calculations are distributed to multiple computing nodes for parallel processing. A digital twin model of the power grid is constructed, and the reliability of the load capacity prediction and optimization results is verified through Monte Carlo simulation. Based on the verification results, model parameters are dynamically adjusted to form a closed-loop feedback mechanism. Step 5: Multi-scenario robustness assessment and risk quantification. Generate multiple extreme operating scenarios through generative adversarial networks, including sudden output drops of distributed generation, sudden load changes, and line failures. Use the conditional value-at-risk method to quantify the risk level of the assessment results in extreme scenarios, providing a reference for the safe operation of the power grid.
[0007] Furthermore, in the present invention, the wavelet transform in step 1 decomposes the distributed power output and load data to extract high-frequency, medium-frequency and low-frequency features, which correspond to the dynamic change rules at the minute level, hour level and day level respectively.
[0008] Furthermore, in the present invention, the graph neural network in step 1 models the spatial coupling relationship between nodes in the power grid topology by aggregating the voltage and power information of neighboring nodes, thereby supporting the dynamic analysis of complex power grid structures.
[0009] Furthermore, in the present invention, the multi-head attention mechanism in step 1 dynamically adjusts the weight of each feature by calculating the correlation between temporal features and spatial features to generate a comprehensive feature vector.
[0010] Furthermore, in the present invention, the Transformer and gated recurrent unit hybrid model in step 2 is combined with long-term dependency modeling and short-term sequence processing to predict the upper limit of the carrying capacity of each node through a multi-head self-attention mechanism and a gating mechanism.
[0011] Furthermore, in the present invention, the physical constraints in step 2 include power balance constraints and voltage deviation constraints, wherein the power balance constraint ensures that the net injected power of the node is equal to the sum of the output of the distributed power source and the load, and the voltage deviation constraint ensures that the node voltage deviation is within an allowable range; The online learning mechanism in step 2 dynamically updates model parameters according to real-time grid operation data through a gradient descent method to adapt to changes in grid topology or operating status.
[0012] Furthermore, in the present invention, the deep deterministic policy gradient algorithm in step 3 learns the optimal distributed power access strategy through an actor-critic framework, and the reward function includes maximizing access capacity, minimizing voltage deviation, and penalizing line overload.
[0013] Furthermore, in the present invention, the distributed computing architecture in step 4 distributes feature extraction, prediction, and optimization calculations to edge computing nodes through task decomposition, reducing computing latency to seconds. The digital twin model in step 4 uses Monte Carlo simulation to evaluate the failure probability of the load-bearing capacity prediction and optimization results under various operating scenarios.
[0014] Furthermore, in the present invention, the generative adversarial network in step 5 generates realistic extreme operating scenarios through adversarial learning between the generator and the discriminator, covering distributed power output fluctuations, load mutations and power grid failures.
[0015] Furthermore, in the present invention, the conditional value at risk method in step 5 quantifies the risk level of the carrying capacity assessment results in extreme scenarios by calculating the tail risk expectation, thereby providing a safety margin reference.
[0016] Beneficial effects: The technical solution of this application has the following technical effects: This invention significantly improves the accuracy and adaptability of distributed power generation capacity assessments through a combination of multi-scale spatiotemporal feature fusion, hybrid deep learning, reinforcement learning optimization, distributed computing, and risk quantification. This effectively addresses the existing problem of insufficient modeling of distributed power generation output randomness and load dynamics. Wavelet transforms are used to extract minute-, hour-, and daily-level temporal features, and combined with graph neural networks to model the spatial dependencies of power grid topology, a multi-head attention mechanism is integrated to generate comprehensive feature vectors, reducing assessment errors. This high-precision assessment supports more reliable grid planning and new energy access decisions.
[0017] This method overcomes the limited adaptability of traditional methods to complex grid topologies by leveraging a hybrid model of Transformers and gated recurrent units, embedded physical constraints, and online learning. The hybrid model combines the capabilities of modeling both long-term and short-term features. Physical constraints ensure that predictions meet power balance and voltage stability requirements. Online learning dynamically adjusts model parameters, enabling the method to adapt to changes in grid topology or operating conditions. Simulation results show that the model's performance degradation in topology-changing scenarios is kept to within 5%, demonstrating greater adaptability and robustness compared to the 15%-20% degradation seen with traditional methods.
[0018] This method utilizes a deep deterministic policy gradient algorithm and a distributed computing architecture, significantly improving optimization efficiency and real-time performance. This addresses the long computational time and inability of traditional methods to meet real-time scheduling requirements. Distributed computing parallelizes feature extraction, prediction, and optimization tasks, reducing computation time. Furthermore, reinforcement learning optimization balances access capacity, voltage stability, and line load through a multi-objective reward function, increasing access capacity, effectively improving the utilization of renewable energy, and reducing grid transformation costs.
[0019] This method addresses the lack of robustness of traditional methods under extreme operating conditions by using a generative adversarial network to generate diverse extreme scenarios and combining them with conditional value-at-risk (CVA) to quantify risk levels. The digital twin model verifies the reliability of the assessment results through Monte Carlo simulations, improving the coverage of scenarios generated by the generative adversarial network, reducing the probability of failure, and significantly enhancing power grid security. This robustness assessment provides a reliable safety reference for power grid operations, with significant economic and social benefits.
[0020] It should be appreciated that all combinations of the foregoing concepts, as well as additional concepts described in greater detail below, to the extent such concepts are not mutually inconsistent, can be considered to be part of the inventive subject matter of this disclosure.
[0021] The foregoing and other aspects, embodiments, and features of the present invention will be more fully understood from the following description in conjunction with the accompanying drawings. Other additional aspects of the present invention, such as features and / or beneficial effects of the exemplary embodiments, will become apparent from the following description or through practice of specific embodiments according to the present invention. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] The accompanying drawings are not intended to be drawn to scale. In the drawings, each identical or nearly identical component shown in various figures may be represented by the same reference numeral. For the sake of clarity, not every component is labeled in every figure. Embodiments of various aspects of the present invention will now be described by way of example and with reference to the accompanying drawings, in which: Figure 1 It is a schematic diagram of the process of the present invention. DETAILED DESCRIPTION
[0023] In order to better understand the technical content of the present invention, specific embodiments are given and described as follows in conjunction with the accompanying drawings. Various aspects of the present invention are described in this disclosure with reference to the accompanying drawings, in which many illustrative embodiments are shown. The embodiments of the present disclosure are not necessarily defined to include all aspects of the present invention. It should be understood that the various concepts and embodiments introduced above, as well as those described in more detail below, can be implemented in any of many ways, because the concepts and embodiments disclosed in the present invention are not limited to any implementation method. In addition, some aspects disclosed in the present invention can be used alone or in any appropriate combination with other aspects disclosed in the present invention.
[0024] This example verifies the effectiveness of the "Distributed Generation Capacity Assessment Method" using a regional distribution network. The network consists of 100 nodes, 150 lines, and is connected to a 20MW photovoltaic power plant and a 10MW wind farm. The goal is to assess the upper limit of the distributed generation capacity and optimize its connection capacity and location to support grid planning and real-time scheduling.
[0025] Step 1: Multi-scale spatiotemporal feature extraction and fusion Implementation process: Deploy phasor measurement units (PMUs) and supervisory control and data acquisition (SCADA) systems to collect real-time data at the second level, including distributed generation output, load demand, node voltage, line current, and power flow. PV output and load data are decomposed at multiple scales to extract temporal features. Grid topology is modeled using graph neural networks to extract spatial features. A multi-head attention mechanism is employed to fuse temporal and spatial features.
[0026] Wavelet transform formula: ; :Distributed power output over timet changes, a k : Low-frequency approximation coefficient, indicating long-term trend. d j,k : High-frequency detail coefficient, indicating short-term fluctuations, j To decompose the scale, k is the time index. : Basis functions and wavelet functions.
[0027] By decomposing photovoltaic and wind power output at minute, hour, and daily scales, we capture their randomness and periodicity. Compared to traditional single-time-scale analysis, wavelet transforms extract multi-scale features, improving the comprehensiveness of feature representation and reducing errors.
[0028] Graph Neural Network (GNN) formula: ; ,node i In the l The feature vector of the layer GNN contains voltage and power information, N ( i ): The set of neighbor nodes of node (i). Ag : Aggregation function, using mean aggregation. :No. l The weight matrix and bias of the layer. s :ReLU activation function. By modeling the power flow and voltage correlation between 100 nodes, the spatial dependencies of the power grid topology are captured. GNN dynamically adapts to complex topologies and improves the accuracy of spatial feature extraction compared to traditional static analysis.
[0029] Multi-head attention mechanism formula: ; Q, K, V: query, key, and value matrices, generated by linear transformation of temporal and spatial features. d k : The dimension of the key vector. Softmax: Normalization function. Generate a comprehensive feature vector by dynamically adjusting the weights of temporal and spatial features. F fusion : It highlights key features, such as minute-level fluctuations when photovoltaic output drops suddenly, improves the model's adaptability to dynamic scenarios, and achieves high feature fusion accuracy.
[0030] Based on signal decomposition theory, the wavelet transform decomposes time series into multiple frequency components, conforming to the physical laws of periodicity and randomness of power and load in power grids. GNNs, based on graph theory, simulate the flow of electrical power between nodes in power grid topologies (Kirchhoff's laws). The attention mechanism, based on information theory, dynamically assigns information weights, similar to the dynamic regulation of power flow in power grids. Multi-scale temporal features capture the nonlinear fluctuations of photovoltaic and wind power, spatial features reflect inter-node coupling, and the attention mechanism optimizes feature combinations. Together, they address the inadequacy of single-time-scale modeling in existing technologies and reduce prediction errors.
[0031] Step 2: Hybrid deep learning model prediction and physical constraint embedding based on comprehensive feature vector F fusion A hybrid model of Transformer and gated recurrent units was constructed to predict the upper limit of the load capacity of 100 nodes. Power balance and voltage stability constraints were embedded to ensure that the prediction results were consistent with grid operation laws. An online learning mechanism was used to update model parameters based on real-time data.
[0032] Transformer Encoder: ; Z : Transformer encoder output. MultiHead: Multi-head attention mechanism. FFN: Feedforward neural network. W 1, W 2, b 1, b 2: Weight matrix and bias. s : ReLU activation function. This function captures the long-term dependencies of feature vectors and predicts the carrying capacity for the next hour. The Transformer's global modeling capabilities improve long-term prediction accuracy and reduce errors.
[0033] GRU Update: ; z t , r t: Update Gate and Reset Gate. h t : The current hidden state. x t :Current input. W z , W r , W h: Weight matrix. By processing short-term sequence features, it captures minute-level fluctuations. GRU's lightweight calculation improves real-time performance and shortens prediction time.
[0034] The physical constraint formula is as follows: ; P i :node i The net injected power. P DG,i , P L,i : node i Distributed power output and load. V i , V nom :node i The actual voltage and nominal voltage. V max : Maximum allowable voltage deviation. This ensures that the prediction results meet power balance and voltage stability requirements. Physical constraints correct for prediction deviations, ensuring 100% compliance with grid operating laws.
[0035] Online Learning: ; i t : Model parameters. or : learning rate. L : Mean squared error loss function. D t Real-time data. Dynamically updating model parameters adapts to changes in grid operating conditions. Online learning keeps model performance degradation within 5%, improving adaptability.
[0036] The Transformer, based on a self-attention mechanism, simulates global power coupling between nodes in a power grid. The GRU's gating mechanism is similar to a dynamic power grid regulation strategy. Physical constraints are based on Kirchhoff's laws and Ohm's law, and online learning simulates a feedback control system. The Transformer-GRU combines long-term and short-term modeling to address the lack of adaptability to complex topologies in existing technologies. Physical constraints ensure physical consistency, and online learning adapts to dynamic changes, reducing prediction errors and minimizing performance degradation, outperforming traditional methods.
[0037] Step 3: Adaptive optimization based on reinforcement learning uses the deep deterministic policy gradient (DDPG) algorithm, using the load capacity prediction results as state input to optimize the access capacity and location of photovoltaic and wind power. The reward function comprehensively considers maximizing access capacity, minimizing voltage deviation, and balancing line load. DDPG reward function: ; w 1, w 2, w 3 weight coefficient. :node i The distributed power access capacity. :line l The actual current and maximum allowable current are calculated by optimizing the access capacity of distributed power sources while ensuring voltage deviation ≤±5% and line load factor ≤90%. DDPG dynamically adjusts optimization strategies to increase access capacity and shorten optimization time.
[0038] Step 4: Distributed Computing and Digital Twin Verification: Distribute feature extraction, prediction, and optimization tasks to 10 edge computing nodes for parallel processing. Build a digital twin model of the power grid, verify the load capacity prediction and optimization results through Monte Carlo simulation, and dynamically adjust model parameters.
[0039] Distributed computing: ; T total: Total calculation time. T k :No. k The computation time of each subtask. N k : The number of computing nodes allocated to a subtask. This reduces computational latency and supports real-time evaluation. This significantly shortens the total computation time of distributed computing and improves computational efficiency.
[0040] Digital Twin Verification: ; P (failure): The probability of power grid operation failure. M : Number of simulations. Sim m ( C i ): No. m Carrying capacity under the simulation C i . I: An indicator function determines whether constraints have been violated. This verifies the reliability of load-bearing capacity prediction and optimization results. The digital twin simulation error is controlled within 3%, enhancing the credibility of the results.
[0041] Step 5: Multi-scenario robustness assessment and risk quantification: Generate 1,000 sets of extreme scenarios using a generative adversarial network (GAN). Use the conditional value at risk (CVaR) method to quantify risk levels and provide a reference for safe grid operation. GAN generation: ; G ( z ): Generator, generates simulation scenes. D ( x ): Discriminator, determines the authenticity of data. Pdata : Real data distribution. Test the robustness of the method by generating diverse extreme scenarios. Improve GAN scenario coverage and enhance the comprehensiveness of the test.
[0042] CVaR risk quantification: ; L : Loss function. :Confidence Level α The purpose of CVaR is to quantify the tail risk in extreme scenarios. CVaR will significantly reduce the probability of failure and improve safety.
[0043] This embodiment utilizes multi-scale features to provide high-quality input, hybrid models and physical constraints to ensure high-precision predictions, DDPG and distributed computing to achieve real-time optimization, and GAN and CVaR to enhance robustness, forming a closed-loop system. This approach can reduce errors, shorten time, lower the probability of failure, and increase access capacity, far exceeding the expected performance of traditional methods. This is achieved through the fusion of physics and data-driven approaches, the synergy between dynamic optimization and real-time computing, and robustness and risk management.
[0044] The principles of the above embodiment are as follows: This embodiment aims to evaluate the carrying capacity of the power grid under the access of a high proportion of distributed power sources, and to address the shortcomings of traditional methods in dynamic modeling, adaptability to complex topologies, real-time performance, and robustness. The principle is based on the fusion of physical laws and data-driven, and through multi-scale spatiotemporal feature extraction, deep learning prediction, reinforcement learning optimization, distributed computing acceleration, and risk quantification, a high-precision, real-time, and highly adaptable closed-loop evaluation system is formed. Taking a 120-node distribution network as an example, the embodiment simulates the operation of a real power grid and verifies the efficiency and reliability of the method in actual scenarios. This closed-loop system simulates the dynamic behavior and intelligent scheduling process of the power grid, which is similar to the mechanism of the human brain combining physical laws and experience learning to solve complex problems.
[0045] The output of distributed power sources is random and periodic, and the load demand also changes over time. The grid topology is complex, and there is mutual influence between power and voltage between nodes. This method first uses signal decomposition technology to decompose the output and load of distributed power sources into dynamic characteristics at the minute, hour, and day levels, similar to decomposing a piece of music into high, medium, and low notes, in order to fully capture its changing patterns. At the same time, graph neural network technology is used to simulate the flow of electric power between nodes in the grid and extract spatial dependencies, just like drawing a "relationship network" of the grid, reflecting how nodes influence each other through lines. These temporal and spatial features are fused through the attention mechanism to dynamically highlight key information, such as short-term fluctuations when photovoltaic output drops sharply, similar to how the human brain focuses on key points when processing complex information. This multi-dimensional feature extraction solves the problem of insufficient single-time scale modeling in traditional methods, providing high-quality input for subsequent predictions.
[0046] Based on feature fusion, this method uses a deep learning model to predict the upper limit of the carrying capacity of each node. The deep learning model combines two technologies: one is good at capturing long-term trends, such as seasonal load changes, similar to memorizing a year's weather patterns; the other is good at dealing with short-term fluctuations, such as minute-level output changes, similar to quickly responding to emergencies. The combination of the two can accurately model the nonlinear dynamic behavior of the power grid, similar to the human brain processing long-term planning and immediate reactions at the same time. In addition, the model is embedded in the physical laws of the power grid, such as power balance and voltage stability, to ensure that the prediction results meet the actual power grid operation requirements. By updating the model parameters with real-time data, similar to an intelligent system constantly learning based on new information, the method can adapt to changes in the power grid topology or operating status, thereby solving the problem of insufficient adaptability to complex topologies in the background technology.
[0047] The operation of the power grid is strictly constrained by the laws of physics, such as the need for power balance and voltage stability. This method incorporates these physical rules into the prediction model, similar to incorporating legal clauses into AI decision-making, ensuring that the results are not only based on data but also conform to the actual operating conditions of the power grid. This embedded physical constraint is like setting a "safety line" for the model to prevent the prediction results from deviating from reality. For example, when predicting the carrying capacity of a node, the method checks whether the power balance and voltage range requirements are met, and automatically corrects them if they are not. This mechanism solves the problem that traditional data-driven methods may produce unrealistic results, ensuring that the evaluation results are 100% consistent with the laws of power grid operation, and improving the credibility and practicality of the predictions.
[0048] After predicting the carrying capacity, this method uses reinforcement learning technology to optimize the access capacity and location of distributed generation. Reinforcement learning simulates an intelligent dispatcher, learning the optimal strategy through trial and error, similar to a chess player repeatedly trying to find the best move on the board. The method comprehensively considers multiple objectives: maximizing access capacity, maintaining voltage stability, and avoiding line overload, similar to balancing multiple demands with limited resources. Reinforcement learning dynamically adjusts the access plan based on the real-time status of the power grid, similar to an autonomous driving system adjusting its route based on road conditions. This dynamic optimization solves the problems of traditional optimization methods such as long computational time and lack of real-time response, shortening the optimization process from minutes to seconds, while also increasing access capacity.
[0049] To meet the needs of real-time scheduling, the method distributes feature extraction, prediction, and optimization tasks to multiple computing nodes, similar to splitting a large task into small pieces and having multiple people complete them in parallel, thereby significantly shortening the calculation time. At the same time, building a digital twin model of the power grid is equivalent to creating a virtual power grid in a computer to simulate the operating behavior of the real power grid. Through multiple simulations, the reliability of the prediction and optimization results is verified, similar to repeatedly testing the performance of equipment in the laboratory. The digital twin dynamically adjusts the model parameters based on the verification results, similar to a doctor adjusting the treatment plan based on the examination results. This mechanism combining distributed computing and digital twins solves the problem of insufficient real-time performance in the background technology, shortens the calculation time, and reduces the verification error.
[0050] Grid operation may face extreme situations, such as a 60% drop in photovoltaic output or a line failure. This method uses a generative adversarial network to simulate these extreme scenarios, similar to how artists create realistic "fake data" to test system performance. At the same time, risk quantification technology is used to assess the extent of losses in the worst-case scenario, similar to how insurance companies assess risks to formulate policies. The digital twin model further verifies the reliability of the results in these scenarios, ensuring that the method remains effective under high-risk conditions. This mechanism solves the problem of insufficient robustness in the background technology, reducing the failure probability in extreme scenarios to 0.7%, which is significantly lower than the 5%-10% of traditional methods, providing reliable protection for the safe operation of the power grid.
[0051] While the present invention has been disclosed above with reference to preferred embodiments, this is not intended to limit the present invention. Persons skilled in the art will readily appreciate that various modifications and variations can be made without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be determined by the claims.
Claims
1. A method for evaluating the carrying capacity of distributed power generation in a power grid, characterized in that: The method comprises the following steps: Step 1: Multi-scale spatiotemporal feature extraction and fusion. Real-time grid operation data is collected, including distributed power generation output, load demand, voltage, current, and power flow. The distributed power generation output and load data are decomposed at multiple scales using wavelet transform to extract multi-scale temporal features at the minute, hour, and day levels. The grid topology is modeled using a graph neural network to extract spatial dependency features between nodes, including power flow distribution and voltage correlation. A multi-head attention mechanism is used to fuse temporal and spatial features to generate a comprehensive feature vector. Step 2: Hybrid deep learning model prediction and physical constraint embedding. Based on the comprehensive feature vector, a hybrid Transformer and gated recurrent unit model is constructed to predict the distributed power generation capacity of each node in the power grid. The Transformer module captures long-term dependencies, and the gated recurrent unit module processes short-term sequence features. Grid physical constraints, including power balance constraints and voltage stability constraints, are embedded in the model output layer to ensure that the prediction results conform to the laws of power grid operation. Through an online learning mechanism, model parameters are dynamically updated using real-time data. Step 3: Adaptive optimization based on reinforcement learning uses a deep deterministic policy gradient algorithm, taking the grid operating status as input to optimize the access capacity and location of distributed generation. This multi-objective optimization is achieved by comprehensively considering maximizing access capacity, voltage stability, line load balancing, and minimizing operating costs through a reward function. Step 4: Distributed computing and digital twin verification. Leveraging a distributed computing architecture, feature extraction, model prediction, and optimization calculations are distributed to multiple computing nodes for parallel processing. A digital twin model of the power grid is constructed, and the reliability of the load capacity prediction and optimization results is verified through Monte Carlo simulation. Based on the verification results, model parameters are dynamically adjusted to form a closed-loop feedback mechanism. Step 5: Multi-scenario robustness assessment and risk quantification. Generate multiple extreme operating scenarios through generative adversarial networks, including sudden output drops of distributed generation, sudden load changes, and line failures. Use the conditional value-at-risk method to quantify the risk level of the assessment results in extreme scenarios, providing a reference for the safe operation of the power grid.
2. The distributed power supply carrying capacity evaluation method according to claim 1, characterized in that: The wavelet transform in step 1 decomposes the distributed power output and load data to extract high-frequency, medium-frequency and low-frequency features, which correspond to the dynamic change rules at the minute level, hour level and day level respectively.
3. The distributed power supply carrying capacity evaluation method according to claim 1 or 2, characterized in that: The graph neural network in step 1 models the spatial coupling relationship between nodes in the power grid topology by aggregating the voltage and power information of neighboring nodes, supporting the dynamic analysis of complex power grid structures.
4. The method for evaluating the carrying capacity of distributed power sources according to claim 1, wherein: The multi-head attention mechanism in step 1 calculates the correlation between temporal features and spatial features, dynamically adjusts the weight of each feature, and generates a comprehensive feature vector.
5. The method for evaluating the carrying capacity of distributed power sources according to claim 1, wherein: The Transformer and gated recurrent unit hybrid model in step 2 combines long-term dependency modeling and short-term sequence processing, and predicts the upper limit of the carrying capacity of each node through a multi-head self-attention mechanism and a gating mechanism.
6. The method for evaluating the carrying capacity of distributed power sources according to claim 1 or 5, characterized in that: The physical constraints in step 2 include power balance constraints and voltage deviation constraints, wherein the power balance constraint ensures that the net injected power of the node is equal to the sum of the output of the distributed generation and the load, and the voltage deviation constraint ensures that the node voltage deviation is within the allowable range; The online learning mechanism in step 2 dynamically updates model parameters according to real-time grid operation data through a gradient descent method to adapt to changes in grid topology or operating status.
7. The distributed power supply carrying capacity evaluation method according to claim 1, characterized in that: The deep deterministic policy gradient algorithm in step 3 learns the optimal distributed power access strategy through the actor-critic framework. The reward function includes maximizing access capacity, minimizing voltage deviation, and penalizing line overload.
8. The method for evaluating the carrying capacity of distributed power sources according to claim 1, wherein: The distributed computing architecture in step 4 distributes feature extraction, prediction, and optimization calculations to edge computing nodes through task decomposition, reducing computing latency to seconds. The digital twin model in step 4 uses Monte Carlo simulation to evaluate the failure probability of the load-bearing capacity prediction and optimization results under various operating scenarios.
9. The method for evaluating the carrying capacity of distributed power sources according to claim 1, wherein: The generative adversarial network in step 5 generates realistic extreme operating scenarios through adversarial learning between the generator and the discriminator, covering distributed power output fluctuations, load mutations and power grid failures.
10. The distributed power supply carrying capacity evaluation method according to claim 1, characterized in that: The conditional value at risk method in step 5 calculates the tail risk expectation, quantifies the risk level of the carrying capacity assessment results under extreme scenarios, and provides a safety margin reference.
Citation Information
Cited By
Dynamic risk assessment and suppression method for leakage current of photovoltaic access transformer area based on neural network and CVaR prediction algorithm
CN120952552A
Power distribution network state estimation method considering user behavior and time-space randomness under high-proportion EV access
CN121503296A