49 results about "Probabilistic load flow" patented technology

The invention discloses a non-parametric probabilistic load flow calculation method considering complex uncertainty for a power system. The method comprises the following steps: firstly, constructing source-load nonparametric probability distribution based on a multivariate Gaussian mixture model; then, constructing an alternating current power flow model under a polar coordinate system in the power system, and performing linear expansion on the alternating current power flow model under the polar coordinate system in the power system at a mean point of source-load non-parametric probability distribution by adopting a first-order Taylor series approximation method to obtain a system operation simplified model based on alternating current power flow linearization of the power system; and finally, according to the linear transformation property of the Gaussian distribution, obtaining the probability distribution of the power flow distribution of the power system under each Gaussian component, and in combination with the total probability law, carrying out weighted summation on the probability distribution under each Gaussian component according to the weight to obtain the non-parametric probabilistic power flow probability distribution of the power system. The method provided by the invention has stronger generalization ability and accuracy, and has important reference significance for operation uncertainty quantification of the power system under complex uncertainty.

The invention discloses a power distribution network optimization scheduling method and system based on multi-target deep reinforcement learning, and relates to the technical field of power distribution network optimization operation, and the method comprises the steps: building a power distribution network operation model and a probabilistic load flow model considering the photovoltaic output and load demand uncertainty, completing the probabilistic load flow calculation under the uncertainty, and obtaining a power distribution network optimal scheduling model; analyzing to obtain a probability density function of node voltage and line power flow of the power distribution network; introducing a utility function based on preference, establishing voltage out-of-limit and line overload risk indexes considering severity weight, and constructing a risk-economic collaborative power distribution network multi-objective optimization operation problem; the decision process of the problem is modeled into a multi-target Markov decision process, a decomposition-based multi-target deep reinforcement learning algorithm is adopted, learning and training of the decision process are performed on reinforcement learning agents, a Pareto strategy set is obtained, an optimal operation strategy is screened out, and optimization regulation and control are performed on the power distribution network. And collaborative optimization of the operation risk and cost of the power distribution network system is realized.

The invention discloses a deep neural network probabilistic load flow calculation method and system, and belongs to the field of power system analysis. The method comprises the following steps: acquiring power system parameters and confidence levels, and determining state variables and orders; establishing and linearizing a nonlinear power flow equation to obtain a Jacobian matrix; a node voltage vector is used as input, branch admittance is used as physical information to be embedded into a deep neural network model based on a multi-head self-attention mechanism and semi-invariant guidance, a Jacobian matrix is solved, and a sensitivity matrix is calculated; calculating and aggregating semi-invariants, and transmitting the semi-invariants to a state variable; and after standardization, obtaining a distribution function by using a six-order Cornish-Fisher series, and calculating a fluctuation interval in combination with a confidence level under opportunity constraint to realize quantitative evaluation. According to the method, the probability load flow calculation complexity is reduced, the limitation of a traditional method in processing the network topology complexity problem is solved, and quantitative evaluation of the probability load flow is realized.

The invention discloses a power system probabilistic power flow method and system based on polynomial proxy and graph parallelism, and belongs to the technical field of power system planning and operation optimization. The method comprises the following steps: establishing a probability distribution model of a bus load prediction error to obtain sample distribution of predicted power; representing the output response quantity of the system as an input polynomial function, and establishing an initial polynomial agent model; determining an optimal configuration point set; mapping all the selected configuration points to an input sample space to obtain a small number of sample points of an input variable; performing deterministic load flow calculation on the sample points to obtain a sample vector of output response; calculating an undetermined coefficient in the proxy model according to the configuration point matrix and the sample vector; and solving the statistical characteristic quantity of the power flow response to obtain the probability distribution of the response. According to the calculation method provided by the invention, the probability distribution of the power flow response can be accurately and efficiently estimated, and convenience is provided for probabilistic power flow calculation of a novel power system under the access of a distributed power supply.

The application discloses a kind of analytic expression probabilistic power flow calculation method, device and storage medium.The application is determined after the mapping relationship between the injection power of node and the operating state of power system by linear power flow model, using first-order polynomial fitting correction method to revise the operating state of power system, make the operating state of the power system after revision be closer to real operating state, according to the mapping relationship between the injection power of node and the operating state of power system after revision, update linear power flow model, carry out analytic expression probabilistic power flow calculation using updated linear power flow model, to effectively improve the accuracy of probabilistic power flow calculation.

The invention provides an urban power distribution network probabilistic load flow calculation method for large-scale access of demand side resources, and belongs to the technical field of power system power distribution network analysis and optimization. The method comprises the following steps: constructing a dynamic Copula model in combination with space-time sequence analysis, introducing a Markov chain, and carrying out multi-dimensional uncertainty coupling modeling; a probabilistic power flow-multi-objective optimization model is constructed, and energy router cooperative control is carried out based on distributed model predictive control; sparse expansion is carried out by adopting error feedback adaptive sampling and sparse Bayesian learning in combination with polynomial chaos expansion, and probability power flow is calculated through OpenDSS; establishing a three-phase probabilistic power flow model and a DG-EV-DR collaborative probability model; and evaluating the extreme scene risk, and visualizing the result through a digital twin platform. According to the method, the accuracy and practicability of distribution network probabilistic load flow calculation in a demand side resource large-scale access scene are effectively improved, and a risk quantification basis is provided for power grid dispatching.

The invention relates to a multi-source scene-driven power distribution network probabilistic load flow calculation method and system, and the method comprises the steps: obtaining the historical data of 24 hours per day in a complete year of load and photovoltaic, and carrying out the clustering division based on a comprehensive similarity index, thereby obtaining a plurality of optical load typical daily output scene sets and the probability distribution thereof; processing data of each scene set to obtain an expected value and a variance of optical charge power; combining the network topology of the power distribution network, taking an expected value as a node injection amount, and performing probabilistic load flow calculation by adopting a two-point estimation method; and carrying out statistical analysis on a calculation result to obtain related statistical data of branch power and node voltage in each typical scene. According to the method, the typical scene probability distribution set is generated by using historical data, the estimation point selection precision and the calculation result reliability are improved, the calculation times are reduced, the efficiency is improved, the actual power grid operation behavior can be better reflected, decision support is provided for a power grid operator, resource allocation is optimized, the cost is reduced, and renewable energy utilization is promoted.

The invention provides a power distribution network voltage out-of-limit probability prediction method considering load fluctuation and photovoltaic output, and relates to the technical field of power distribution network safety. The method comprises the following steps: constructing a time-varying Gumbel-Copula joint distribution function according to a Spearman rank correlation coefficient, obtained by calculation, of a load and photovoltaic output; based on a time-varying Gumbel-Copula joint distribution function, probability distribution of the load and probability distribution of the photovoltaic output are reconstructed through a Hermite polynomial, and parallel probabilistic power flow solving is carried out; and calculating the voltage out-of-limit probability of each node according to the result of the parallelization probabilistic power flow solution. According to the method, dynamic coupling characteristics of different time periods are considered, a time-varying Gumbel-Copula joint distribution function is introduced, probability distribution of loads and probability distribution of photovoltaic output are reconstructed through a Hermite polynomial, the influence of intermittent superposition of load fluctuation and photovoltaic output can be overcome, and real-time prediction of the voltage out-of-limit probability can be accurately completed in extreme weather.

The invention discloses an integrated energy system situation awareness method based on a message passing graph-long short-term memory neural network, and the method comprises the following steps: firstly, obtaining a load data set and topological information of an integrated energy system from a historical database, constructing a probabilistic load flow calculation physical model of the integrated energy system, and calculating to obtain a load flow data set of the integrated energy system; secondly, taking load data and branch admittance as input, taking node voltage amplitude and phase angle as output, and using a deep neural network multi-topology joint training method to train the DNN; and finally, constructing a topological graph data set of the integrated energy system, obtaining an accurate feature vector of each node based on an MPNN layer, and taking an output node voltage of the MPNN layer as an input of an LSTM layer to realize accurate situation prediction of the integrated energy system.

The invention relates to the technical field of power control, in particular to an active regulation space quantitative evaluation method considering active voltage coupling influence, and the method comprises the steps: firstly constructing a steady-state power flow equation containing DC control characteristics, correcting a Jacobian matrix through introducing a commutation bus power correction, and building a voltage active sensitivity index; probabilistic load flow calculation is carried out in combination with a new energy output probability model, and a voltage weak node is accurately identified by using an impedance mode margin index; and generating a PV curve by adopting a continuous power flow method, superposing a static voltage safety constraint condition, and performing intersection operation on a unit output interval and a reserve capacity interval in a safe operation range to obtain an effective active power regulation space, thereby accurately quantifying the actual regulation capability on the premise of ensuring the voltage safety, and further realizing high-precision voltage regulation. And the safety and the economical efficiency of system operation are effectively improved.

The present invention relates to a probabilistic power flow method and system for power systems based on polynomial surrogate and graph parallelism, belonging to the technical field of power system planning and operation optimization. It includes establishing a probability distribution model of the bus load prediction error to obtain the sample distribution of the predicted power; representing the output response quantity of the system as a polynomial function of the input and establishing an initial polynomial surrogate model; determining the optimal set of collocation points; mapping all selected collocation points to the input sample space to obtain a small number of sample points of the input variables; performing deterministic power flow calculations on the sample points to obtain the sample vector of the output response; calculating the undetermined coefficients in the surrogate model according to the collocation point matrix and the sample vector; and solving the statistical characteristic quantities of the power flow response to obtain the probability distribution of the response. The calculation method provided by the present invention can accurately and efficiently estimate the probability distribution of the power flow response, facilitating the probabilistic power flow calculation of a new power system under the access of distributed power sources.

The application discloses a deep neural network probability power flow calculation method and system, and belongs to the field of power system analysis. The method comprises the following steps: acquiring power system parameters and a confidence level, determining state variables and order; establishing and linearizing a nonlinear power flow equation to obtain a Jacobian matrix; taking a node voltage vector as input, embedding branch admittance as physical information into a deep neural network model based on a multi-head self-attention mechanism and semi-invariant guidance, solving the Jacobian matrix, and calculating a sensitivity matrix; calculating and aggregating semi-invariants, and transferring the semi-invariants to state variables; after standardization, obtaining a distribution function by using a six-order Cornish-Fisher series, and under an opportunity constraint, combining the confidence level to calculate a fluctuation interval and realize quantitative evaluation. The application reduces the complexity of probability power flow calculation, solves the limitations of traditional methods in dealing with network topology complexity problems, and realizes quantitative evaluation of probability power flow.

The invention discloses an energy storage power station collaborative planning method and system based on uncertainty propagation analysis. In order to solve the problems that an existing energy storage planning method is indefinite in physical mechanism and insufficient in interpretability, the planning method comprises the steps that operation data of a power system are obtained, and an analysis alternating current probabilistic power flow model used for establishing an analysis relation between system voltage statistical characteristics and line power statistical characteristics is constructed based on the operation data; constructing a propagation matrix representing the uncertainty propagation characteristics of the system based on the analysis of the AC probabilistic power flow model; performing spectral analysis on the propagation matrix to identify one or more dominant propagation modes which play a dominant role in the uncertainty of the system; and based on the one or more dominant propagation modes, determining a planning scheme of at least one type of energy storage power station, the category of the planning scheme including the access position capacity of the energy storage power station. According to the method, energy storage configuration is guided by using an uncertainty physical propagation mechanism, and the risk control effect, the calculation efficiency and the engineering interpretability of a planning scheme are remarkably improved.

The invention relates to a probabilistic load flow calculation method for new energy and load correlation, and the method specifically comprises the steps: building a probabilistic model of new energy and load based on the distribution types and parameters of the new energy and load, inputting network structure parameters, the probabilistic model information of the new energy and load, and correlation coefficient information, the method comprises the following steps of: setting a median Latin hypercube sampling scale and an iteration number marking variable, then sampling mutually independent random variables such as new energy and load and random variables such as new energy and load with a correlation so as to generate random samples, and finally, based on a Newton-Raphson method, calculating a maximum iteration number of the new energy and the load so as to obtain a maximum iteration number of the new energy and the load. Performing power flow calculation on the obtained random samples in sequence, finally performing statistics on power flow results such as node voltage, line transmission power and line loss rate obtained by each power flow calculation, drawing a probability density curve, and performing probability power flow calculation of new energy and load correlation by using the probability density curve; the method has the advantages of being accurate in calculation, fast and efficient.

The invention provides an electric power system operation risk assessment method and system, and the method comprises the steps: carrying out the probabilistic load flow calculation based on a probability density function corresponding to the output data of an electric power system through employing a Latin hypercube algorithm, and obtaining the probabilistic load flow data of the electric power system; according to the probabilistic power flow data of the power system, calculating a corresponding operation risk assessment index value; performing risk assessment on the power system according to the operation risk assessment index value; according to the method, the Latin hypercube algorithm is adopted in the probabilistic load flow calculation process of the power system, the uncertainty in the grid connection process can be considered, the process of probabilistic load flow calculation can be simplified, the calculation precision and the sampling efficiency are improved, and then a more accurate probabilistic load flow calculation result is obtained; the accuracy of power system operation risk assessment is improved.

The application discloses an asymmetric medium-voltage three-phase distribution network probability power flow calculation method containing single-phase photovoltaic access, and comprises the following steps: 1, based on historical power data of photovoltaic, weight values are obtained by an improved entropy weight method, and then the output probability density function of distributed photovoltaic is obtained by LightGBM prediction; 2, for the medium-voltage three-phase distribution network with single-phase photovoltaic access, the uncertainty of photovoltaic output and access position is considered, the neutral point voltage is alternately iterated with Newton method, and a three-phase distribution network power flow model is constructed; 3, integral points and weights of point estimation method are determined, space transformation is carried out by Nataf inverse transformation, and power flow distribution is obtained from the three-phase distribution network power flow model; each order statistical moment is calculated, Gram-Charlier series fitting is adopted, and the probability distribution of the distribution network system is obtained. The application considers the influence of uncertain single-phase photovoltaic access to obtain the probability power flow distribution, and has positive significance for the study of power flow, probability optimization problem, system operation and safety evaluation of the neutral point not directly grounded distribution network system.

The invention discloses a probabilistic power flow algorithm based on a linear power flow model and a total probability formula, and aims at a scene that a conventional probabilistic power flow calculation method based on semi-invariant cannot be carried out due to the ill-conditioned Jacobian matrix in probabilistic power flow analysis of an active power distribution network. And an optimal state variable function is selected to improve the calculation precision. A total probability formula is introduced in probability calculation, N output interval combinations are obtained by performing segmentation processing on the new energy unit, and a joint conditional probability density function and each-order semi-invariant of the new energy unit under the N output interval combinations are calculated. The method comprises the following steps of: calculating a semi-invariant of a state variable based on a linear power flow model under each output interval combination, finally fitting a distribution function by adopting a Gram-Charlier (GC) series to obtain N conditional probability distribution functions of the state variable, and aggregating by adopting a total probability formula to obtain a complete probability density function. According to the method, the precision of probabilistic power flow analysis is improved, and the technical method has relatively high implementability.

The application relates to the technical field of optimal scheduling of distributed power grids, and specifically discloses a two-stage optimal scheduling method for distributed power grids based on a probabilistic power flow and a WOA-PPSO algorithm, which comprises the following steps: constructing a probabilistic power flow model, calculating the probability distribution characteristics of node voltage and line flow in the power grid containing wind power, photovoltaic power and load randomness based on the semi-invariant method and Gram-Charlier series expansion. The application introduces the probabilistic power flow modeling into the optimization constraint of the scheduling algorithm, and responds to the uncertainty that may exist in the power grid in real time; by constructing a two-stage scheduling algorithm, the global optimal scheduling plan is generated based on the WOA algorithm in the day-ahead scheduling, and the deviation caused by the uncertainty is quickly responded on the basis of the optimal scheduling plan in the real-time scheduling of the day; and the result of the day-ahead scheduling is taken as the reference starting value of the real-time scheduling of the day, and the projection method is combined with the PSO algorithm to construct the PPSO algorithm, so that the solving speed in the real-time scheduling of the day is maximally improved.

The invention provides an active power distribution network accurate reconstruction optimization method and device, and the method comprises the steps: generating random sample data corresponding to the output of a distributed power supply and the load characteristics of a power grid according to the operation parameters of an active power distribution network, and generating a probabilistic power flow input variable set of the active power distribution network according to the random sample data; performing probabilistic load flow calculation based on the input variable set to obtain probabilistic load flow index information of each node voltage and line load flow; generating an electric energy quality comprehensive evaluation index of the active power distribution network according to the probabilistic power flow index information; establishing a multi-target optimization model for accurate transformation of the active power distribution network based on the comprehensive evaluation index of the power quality by taking the highest and minimum transformation cost of the power quality as a target; and solving the multi-objective optimization model by adopting an improved particle swarm algorithm to obtain a precise reconstruction scheme of the active power distribution network. According to the technical scheme provided by the invention, refined and efficient transformation decision of the active power distribution network under high uncertainty is realized.

The application discloses a kind of AC-DC hybrid system probabilistic power flow calculation method considering new energy boundedness and correlation, comprising the following steps: 1) obtaining AC-DC hybrid system basic information, determine the scaling factor, and utilize scaling unscented transformation method to select sample points on standard normal distribution;2) calculate boundary parameter, convert the selected sample points to original probability space, obtain original probability space sample points;3) establish the power conversion model of wind farm and photovoltaic power station and the deterministic power flow model of AC-DC hybrid system;4) input wind speed, light intensity into the power conversion model of wind farm and photovoltaic power station, obtain wind power and photovoltaic output data;5) input load data, wind power and photovoltaic output data into the deterministic power flow model of AC-DC hybrid system, carry out probabilistic power flow analysis and calculation.The application can analyze high-dimensional probabilistic power flow considering new energy boundedness and correlation when large-scale new energy is accessed to AC-DC hybrid power grid.

Disclosed in the present disclosure are an apparatus and method for managing voltage of a hybrid distribution network. According to an aspect of the present disclosure, provided is a method for managing voltage of a hybrid distribution network, the method comprising: receiving monitoring information related to a hybrid distribution network; carrying out probabilistic power flow calculation on the basis of the received monitoring information; determining, on the basis of a result of the probabilistic power flow calculation, whether a voltage violation occurs in the distribution network; on the basis of whether the voltage violation occurs, selectively determining whether the maximum voltage or the minimum voltage in the distribution network violates a voltage management range; and on the basis of whether the maximum voltage or the minimum voltage in the distribution network violates the voltage management range, selectively deriving a droop gain by using an optimization model.

The invention relates to the technical field of power grids, in particular to an R-vine Copula-based probabilistic load flow calculation method and system for a power system. According to the method, wind power plant prediction error data including short-term, medium-term and long-term prediction errors and actual output data in a power system are obtained, and an R-vine Copula model is used for modeling to generate a wind power plant output scene; secondly, grouping the wind power plant output scenes by adopting a K-means grouping algorithm containing distance constraints to obtain a group center scene and corresponding group members, and performing probabilistic load flow calculation through a load flow approximation algorithm retaining nonlinear terms; and finally, performing optimal power flow calculation based on a wait-and-tree model, directly reflecting a wind power plant output scene in an economic dispatching model, and simultaneously satisfying constraint conditions such as a system power flow equation, line power, node voltage and the like by minimizing prediction scene fuel cost and the sum of fuel cost and punishment cost of each scene. The problem that a traditional Copula function is insufficient in flexibility when depicting a complex multi-dimensional correlation structure is effectively solved.

The application relates to the technical field of optimal scheduling of distributed power grids, and specifically discloses a two-stage optimal scheduling method for distributed power grids based on a probabilistic power flow and a WOA-PPSO algorithm, which comprises the following steps: constructing a probabilistic power flow model, calculating the probability distribution characteristics of node voltage and line flow in the power grid containing wind power, photovoltaic power and load randomness based on the semi-invariant method and Gram-Charlier series expansion. The application introduces the probabilistic power flow modeling into the optimization constraint of the scheduling algorithm, and responds to the uncertainty that may exist in the power grid in real time; by constructing a two-stage scheduling algorithm, the global optimal scheduling plan is generated based on the WOA algorithm in the day-ahead scheduling, and the deviation caused by the uncertainty is quickly responded on the basis of the optimal scheduling plan in the real-time scheduling of the day; and the result of the day-ahead scheduling is taken as the reference starting value of the real-time scheduling of the day, and the projection method is combined with the PSO algorithm to construct the PPSO algorithm, so that the solving speed in the real-time scheduling of the day is maximally improved.

The application discloses an AC-DC hybrid power grid risk assessment method, device, equipment and medium. According to the historical data of the random input variables of a power system, a first optimization model minimizing the difference between the score moments of the input variables and the estimated values is established; by solving the first optimization model, the optimal score moment proportion parameters and weight adjustment parameters are obtained, and a plurality of sample points and their weight parameters are obtained according to the solving result; the score moments of the random output variables are calculated according to the plurality of sample points and their weight parameters; the probability density result when the information entropy of the random output variables is maximized is calculated by taking the score moments of the random output variables as constraints, and the probability density result is reconstructed; according to the probability density result, the probability of the bus voltage and line flow of the power system exceeding the limit is calculated, and the operation state of the power system is evaluated. The application improves the efficiency and accuracy of the probability flow calculation, thereby improving the accuracy of the power grid risk assessment.

The application discloses a kind of offshore wind power and frequency's probabilistic power flow calculation method and device, wherein the method comprises: respectively constructing the active-frequency static characteristic of unit and the active-frequency static characteristic of load;Static frequency characteristic is considered to build power flow model based on the active-frequency static characteristic of unit and the active-frequency static characteristic of load;According to the power flow model considering static frequency characteristic, decoupling linear power flow model considering static frequency characteristic is derived;The decoupling linear power flow model is analyzed based on UT transformation and NATAF transformation to obtain the probabilistic power flow analysis result.The application is based on the active-frequency static characteristic of unit and the active-frequency static characteristic of load to build the power flow model considering static frequency characteristic, and decoupling linear power flow model considering static frequency characteristic is derived, can effectively improve the calculation efficiency of probabilistic power flow, and then can improve the efficiency of probabilistic power flow analysis in random scene.

The invention belongs to the technical field of power system reliability, and particularly relates to a power system power supply weak link identification method and device based on a semi-invariant method.The method comprises the following steps that power source parameters are set, a power distribution network topological structure is obtained, and a system node admittance matrix is obtained according to the power distribution network topological structure; carrying out load flow calculation based on a Newton-Raphson method to obtain a voltage amplitude and a phase angle of each node; performing power system probabilistic load flow calculation based on a semi-invariant method to determine the weak point probability of each node; and determining weak nodes according to the weak point probability of each node. According to the method, the weak link can be accurately and rapidly identified in a complex power system, and particularly under a distributed photovoltaic system, the method has extremely high adaptability to the conditions of high-proportion new energy and load fluctuation. Therefore, planning and maintenance of the power system are more accurate, and potential risks are effectively reduced.

This invention discloses a reactive power optimization method for distribution networks based on probabilistic power flow sensitivity analytical transformation, belonging to the field of power system optimization and dispatching technology. The method includes: considering the impact of source-load power uncertainty on distribution network dispatching, constructing a reactive power optimization model based on chance constraints, and using probabilistic power flow sensitivity to characterize the probability distributions of voltage and branch power random variables respectively; linearizing the quadratic nonlinear branch security constraints using a regular polygon approximation method to decouple the optimization variables from the random variables; establishing analytical expressions for voltage and branch security chance constraints through affine transformation of probabilistic power flow sensitivity; and analytically transforming the nonlinear chance constraints into deterministic constraints based on probability transformation theory, transforming the original problem into a mixed-integer second-order cone programming model for solution. This invention can fully tap the potential of photovoltaic reactive power regulation, significantly improve voltage stability and reduce network losses, while also having a computational efficiency advantage over the traditional sample mean method.

The present invention discloses a probabilistic power flow calculation method and system based on charging station node fault analysis. The method comprises: first, establishing a road network model and a distribution network model based on graph theory, and considering the coupling relationship between the two to establish a road-to-electricity coupling model; then, constructing an electric vehicle travel chain model based on a Markov chain. On this basis, combining the road-to-electricity coupling model and considering the charging psychology of users, a method for characterizing the real-time dynamic response of electric vehicle load under N-1 faults is proposed. In particular, a probabilistic power flow calculation method based on charging station node fault analysis is used to simulate the electric vehicle load curve after a charging station node fault occurs in the distribution network. Finally, a Monte Carlo method is used to perform probabilistic power flow calculation. The power flow calculation results are used to analyze the secondary impact of N-1 faults, especially the spatiotemporal characteristics of electric vehicles under charging station node faults, on the distribution network power flow. A voltage evaluation index is then constructed to evaluate the importance of charging station nodes.

The invention discloses a multi-supply-area interconnected power distribution network probabilistic load flow calculation method considering wind and light uncertainty. The method comprises the following steps: constructing a power distribution network deterministic topology model interconnected through a flexible multi-state switch; establishing probability models of wind power generation, photovoltaic power generation and load; the probability model is incorporated into a power distribution network deterministic topology model, and a power distribution network uncertainty model with multiple interconnected supply areas is obtained; according to the uncertainty model of the power distribution network, generating a sampling scene set representing the random operation state of the power distribution network by using a three-point estimation method; according to the sampling scene set, random power is injected into the network, deterministic load flow calculation of an improved forward-backward sweep method is executed, calculation results of all scenes are aggregated, and the steady-state operation index of the interconnected power distribution network is obtained.

The invention discloses a power system probabilistic load flow calculation method based on a calculation force load random model. The method comprises the following steps: acquiring illumination intensity data, wind speed data and basic data of a power grid system; establishing a probability distribution model of wind power and photoelectric output and an output probability distribution model of a common load in the line; establishing a probability model of the data center load; constructing a linearized probabilistic power flow model of the power system structure; according to the linearized probabilistic power flow model, calculating the original moment and the center distance of an input variable to obtain the semi-invariant of each order, and further obtaining a state variable and the semi-invariant of the branch power flow; and obtaining a probability density function and a cumulative distribution function of the state variable and the branch power flow according to the state variable and the semi-invariant of the branch power flow. The method not only considers the photovoltaic and wind power uncertain power injection of the power distribution network, but also considers the random model of the calculation load of the data center, so that the result is closer to reality, the calculation accuracy is high, and the speed is high.