50 results about "System analysis" patented technology

The invention discloses an active island detection method and system based on harmonic impedance characteristic identification, and the method comprises the steps: analyzing the harmonic impedance difference of grid-connected points in a grid-connected state and an island state, and building a state criterion based on resonant frequency deviation and impedance amplitude through the comparison of the frequency response characteristics of island impedance and grid-connected impedance; fitting the grid impedance into an RLC parallel model in a selected frequency band, and mapping the topological difference of the power grid into a parameter difference; embedding a low-voltage ride-through strategy in the control of the voltage source converter, and adjusting reactive current in a grading manner according to the voltage drop degree of a grid-connected point; fundamental waves and harmonic waves are separated through a cascade notch filter, two synchronous harmonic waves are injected into the system through constant current control, and it is ensured that injection signals of a multi-voltage source converter are in the same phase in a phase locking link; and solving an overdetermined equation set based on the double-frequency response data to identify RLC parameters, setting an island criterion, and synchronously completing island judgment in a low-voltage ride-through time window. Detection precision is improved, dynamic response is optimized, and power generation efficiency is improved.

The invention belongs to the technical field of electric power system analysis, and mainly relates to a new energy consumption-oriented high-capacity energy storage partition optimization configuration method, which comprises the following steps of: firstly, dividing a power grid model into a plurality of regions according to geographic and electrical characteristics of the selected power grid model, and determining regional energy storage requirements after determining partitions of the power grid model; further constructing a total cost optimization scheduling model of the maximum new energy consumption and the minimum energy storage system, determining constraint conditions of the target according to a load balance constraint, an energy storage system capacity constraint and a new energy processing limit, processing by using a mixed integer linear investment and operation cost planning method, and solving an optimal solution through iteration; more importantly, after the optimization scheduling model is solved preliminarily, the energy storage configuration function of each region is adjusted in real time according to time, system load and new energy consumption amount by updating the energy storage configuration step by step, and finally, the precision of energy storage configuration parameters is guaranteed.

The invention discloses a power generation power prediction method for wind power generation, and relates to the field of power generation power prediction, and the method comprises an environment monitoring step, a preliminary analysis step and a power prediction step. The prediction difficulty coefficient corresponding to the generation power prediction period is obtained by combining the prediction time length of the wind power generation device for systematic analysis, a data basis is effectively provided for subsequent generation power prediction, and historical environment information and a historical electrical parameter set used by the wind power generation device are systematically analyzed and screened to obtain a prediction difficulty coefficient corresponding to the generation power prediction period. The electrical parameter sets of different historical time points and the interval duration between the different historical time points and the data interception time node of the power generation device are further analyzed, so that the accuracy of the corresponding power generation power prediction result of the wind power generation device is effectively improved, and the normal development of wind power generation is guaranteed.

The invention discloses a waterworks disinfection process optimization method and system, and the method comprises the steps: carrying out the polynomial fitting of collected unit consumption data of post-chlorination, and obtaining a frequency domain input through Laplace transformation; respectively inputting the input quantity into a pre-constructed library entering residual chlorine attenuation linear time-invariant system (LTI) and a factory leaving water residual chlorine attenuation LTI system to obtain residual chlorine response of the Laplace domain; and outputting a predicted reservoir entering residual chlorine value and a predicted factory leaving water residual chlorine value in a time domain through inverse Laplacian transformation, and dynamically adjusting a post-chlorination dosing strategy according to the predicted reservoir entering residual chlorine value and the predicted factory leaving water residual chlorine value. According to the method, data-driven modeling and frequency-domain system analysis are combined for the first time, the technical bottleneck of residual chlorine attenuation quantitative prediction in the internal process links of a water plant is broken through, precise closed-loop control over disinfectant adding is achieved, the operation cost is remarkably reduced while water quality safety (microbial reproduction and disinfection by-product generation are inhibited) is guaranteed, and the method is suitable for large-scale popularization and application. And core technical support is provided for intelligent water plant construction.

The invention relates to the technical field of servo system motion planning, and discloses a point-to-point linear motion time B-spline instruction time-frequency domain active design method, and the construction process of a motion instruction generation model comprises the steps: defining a motion instruction through a time B-spline curve, and obtaining an expression of the motion instruction; a feeding system is regarded as a dual-mass under-damping flexible system, and the resonance frequency band of the system is analyzed; according to the resonance frequency band, constructing a wavelet packet coefficient matrix, and extracting resonance frequency band energy of the motion instruction; using a least square method to minimize the energy, capable of exciting system resonance in the time-frequency domain, of the motion instruction, introducing kinematics constraints, and establishing a motion instruction generation model. According to the method, a frequency band which is easily excited to generate resonance in a motion instruction is minimized in a frequency domain, energy optimization of the motion instruction is realized in a time domain, and the resonance phenomenon which is easily generated in a high-speed motion process is fundamentally reduced.

The invention provides a flexible connecting rod robot nonlinear system control method and system based on an observer, and belongs to the technical field of robot control, and the method comprises the steps: building a flexible connecting rod robot quasi unilateral Lipschitz nonlinear system dynamics model; creating a state observer based on the state vector of the nonlinear system; constructing an error system and an error expansion system containing predictable target signal information; designing a state feedback controller, and substituting the state feedback controller into the error expansion system to obtain a closed-loop system; analyzing stability and H-infinity performance conditions of the closed-loop system to obtain a state feedback controller gain matrix; and returning the gain matrix of the state feedback controller to the quasi unilateral Lipschitz nonlinear system to obtain a predictive controller based on the observer, and tracking and controlling the target signal. According to the method, the control performance of a closed-loop system is improved by combining a quasi single-side Lipschitz condition and utilizing predictable information of a target signal.

The invention belongs to the technical field of electric power system analysis, and mainly relates to a new energy consumption-oriented high-capacity energy storage partition optimization configuration method, which comprises the following steps of: firstly, dividing a power grid model into a plurality of regions according to geographic and electrical characteristic data of the selected power grid model, determining regional energy storage requirements after determining the partitions of the power grid model, and determining the energy storage requirements of the regions; further constructing a total cost optimization scheduling model of the maximum new energy consumption and the minimum energy storage system, determining constraint conditions of the target according to a load balance constraint, an energy storage system capacity constraint and a new energy processing limit, processing by using a mixed integer linear investment and operation cost planning method, and solving an optimal solution through iteration; more importantly, after the optimization scheduling model is solved preliminarily, the energy storage configuration function of each region is adjusted in real time according to time, system load and new energy consumption amount by updating the energy storage configuration step by step, and finally, the precision of energy storage configuration parameters is guaranteed.

The invention relates to the technical field of power system analysis, and particularly provides a power distribution area voltage out-of-limit cause analysis method and device, and the method comprises the steps: extracting corresponding feature data when a voltage out-of-limit event occurs in a power distribution area; analyzing a voltage out-of-limit cause of the power distribution area based on the characteristic data; wherein the characteristic data comprises a load three-phase unbalance degree, a distribution transformer load rate, a power factor, a load fluctuation rate, a measured voltage value, a maximum phase and minimum phase voltage difference, voltage out-of-limit event occurrence time, a reactive power, a measured voltage value out-of-limit frequency and a measured voltage value out-of-limit duration time. According to the technical scheme provided by the invention, the distribution transformer side voltage cause is identified, and a foundation is laid for comprehensively improving the electric energy quality level of a distribution transformer area.

The invention discloses a short-circuit current calculation method based on a power frequency model, and belongs to the technical field of power system analysis. The method comprises the following steps: collecting basic parameters of a power system under power frequency, wherein the basic parameters comprise system rated voltage, impedance parameters of each element and a system topological structure; constructing a power frequency equivalent model of the power system based on the power frequency parameters, and forming equivalent circuit representation; determining the type and position of a short-circuit fault; based on a power frequency equivalent model, a short-circuit current value is calculated through a circuit analysis technology, an asymmetric fault is processed by adopting a symmetric component method, and the influence of transition resistance can be considered; and outputting a short-circuit current calculation result for system protection or equipment verification. According to the method, the calculation process is simplified, the calculation efficiency is improved, the calculation precision under the power frequency is ensured, and the method has high engineering practical value.

The invention relates to the technical field of vehicle electrical system analysis, and particularly discloses a vehicle electrical performance analysis method based on big data, which comprises a data preparation stage, a data preprocessing stage and a data application stage, and is characterized in that based on vehicle big data information, data processing, data application innovation, data information screening and combination are carried out, and vehicle electrical performance analysis is carried out. According to the method, the use frequency of each electric appliance is obtained, optimization of electric balance calculation from estimated value calculation to refined calculation in each subdivision state is achieved, and on the basis that the performance of the whole vehicle is met, the matching problem caused by redundant design of a generator and a storage battery and estimation errors is avoided; through data information cleaning, integration and data graphical design, on-line monitoring, remote diagnosis, abnormity analysis and electric equipment use condition analysis of the vehicle are realized, improvement of product design quality is assisted, cost is saved, and combination of product design and product operation is realized.

The application belongs to the field of wind turbine fault identification, and relates to a fault identification method and system based on a doubly-fed wind turbine, comprising: obtaining operation data of the doubly-fed wind turbine, and processing the operation data to obtain operation time series data set; obtaining associated feature labeling data based on the association between the operation data; constructing a multi-system collaborative integration model and initializing to obtain an initial collaborative integration model; training the initial collaborative integration model to obtain a trained collaborative integration model; inputting a current operation feature vector of the doubly-fed wind turbine into the trained collaborative integration model to obtain generation error and prediction error; calculating an initial fault score based on the generation error and the prediction error, and determining a system of the doubly-fed wind turbine that has occurred a fault based on the initial fault score; to solve the limitation of single-system analysis, improve fault identification accuracy, and determine the main system and the secondary system that cause the fault.

The invention relates to the technical field of circuit system analysis, in particular to a method, a system and equipment for measuring parameters of a transformer. An excitation current source is applied to the primary side of a to-be-measured transformer, an open circuit of the secondary side is kept, the alternating voltage of the secondary side is measured, the real part and the imaginary part of the ratio of the alternating voltage of a secondary side winding to the alternating input current of a primary side winding are calculated, and the excitation resistance and the excitation inductance of a magnetic core are obtained according to the real part and the imaginary part. Stopping applying excitation, measuring port resistance and inductance from a primary side port, and calculating primary side leakage resistance and leakage inductance in combination with obtained excitation parameters; and opening the primary side, measuring the port resistance and inductance from the secondary side port, and calculating the secondary side leakage resistance and leakage inductance in combination with excitation parameters. The testing method is easy and convenient to operate, the calculation process is simplified, and the parameter measuring precision of the transformer is effectively improved.

This invention relates to the field of power system analysis, specifically to a method for determining the transient stability of a power grid based on a critical credibility index. The method includes: calculating the transient instability probability using real-time acquired transient response trajectories of electrical quantities at the initial stage of a fault and a trained transient stability discrimination model; predicting a transient stability label based on the transient instability probability; evaluating the predicted transient stability label to obtain the final transient stability discrimination result. This invention significantly improves the accuracy and generalization ability of the transient stability discrimination model by constructing an electromechanical transient simulation dataset covering multiple operating modes and fault types, and using transient response trajectories of electrical quantities as core feature inputs. The introduction of a critical credibility index quantifies the uncertainty of the model output results, reducing the possibility of instability conditions being misclassified as stable conditions, and improving the conservatism and accuracy of the discrimination results.

The technology is directed to a system that enhances input(s) received from a device. The system analyzes the input to extract features such as acoustic properties and expressive parameters. The system upscales the input based on the extracted features and translates the enhanced audio into text while maintaining the original context and satisfying predetermined language guidelines. The system generates synthesized speech that preserves the context of the original input and presents the synthesized speech via a speaker of the device. The system can process communications containing hybrid multimodal inputs by identifying the communication mode of each input and extracting contextual features from the multimodal inputs. The system generates a message for communication by translating the extracted contextual features into a predefined communication format and presents the message via the device.

The invention discloses an impedance response calculation method for a three-phase alternating current system model of a flexible direct current battery swap station, and relates to the technical field of power system analysis and control. The method comprises the following steps: taking a three-phase alternating current system model of the flexible direct current battery swap station as a directed graph, obtaining tree branches and connecting branches of the directed graph, and determining a branch admittance matrix of the system model according to the tree branches and the connecting branches; performing cut set selection on the directed graph, determining a cut set matrix of the system model, and determining a cut set voltage column vector of the system model according to an input power supply column vector, a branch admittance matrix and the cut set matrix of the system model; according to the relation between the cut-set voltage and the branch voltage and the cut-set voltage column vector of the system model, the voltage and the current on the input end branch of each phase of the system model are determined, and therefore the input impedance response of each phase of the system model is determined. According to the method, the calculation efficiency of the impedance response of the three-phase alternating current system model of the flexible direct current battery swap station can be improved.

The invention discloses an analysis method for a multistage section coupling rule under static voltage stability and a related device, and relates to the technical field of power system analysis, and the method comprises the steps: obtaining a topological structure of a new energy delivery system and the output of each station, and carrying out the disassembly and decoupling of reactance into independent branches; and the independent branch comprises a field station, a reactor and a power grid access point. And calculating the static voltage stability limit of each branch, determining a system section power expression, and performing adjustment. According to the sequence of reaching the static voltage stability limit by the new energy station in the new energy delivery system, the power expression of each section and the output of each new energy station at the moment, determining the limit formula of each section; and determining a multi-stage section coupling rule change curve of the section limit according to the section limit formula of each stage. The method can effectively evaluate and predict the coupling rule of the multi-stage section under the static voltage stability condition.

The invention discloses a system voltage stability evaluation method and device and a storage medium, and relates to the technical field of power system analysis. The method is used for a power system comprising new energy power generation equipment and a system electrical load, the new energy power generation equipment and the system electrical load are connected to a power grid through a grid-connected point, and the method comprises the following steps: obtaining working parameters of the new energy power generation equipment and the system electrical load and system parameters of the power system; determining a voltage stability index about the node voltage at the grid-connected point according to the working parameters and the system parameters; and introducing a voltage stability index to carry out system voltage stability evaluation on the power system to obtain an evaluation result. According to the method, the influence of the new energy power generation equipment and the system power load is comprehensively considered to define the voltage stability index, and more comprehensive and more accurate system voltage stability evaluation can be performed on the power system.

The invention provides a method and system for predicting the separation time of an industrial machine through a laboratory electromagnetic classificator test. The method comprises the following steps of separation preparation, ore pulp preparation, cyclic separation, sampling, ore discharging, system closing, analysis and test and test data processing. The system further comprises a control cabinet and an electromagnetic classificator, a concentrate outlet of the electromagnetic classificator is connected with the ore feeding groove and the concentrate collecting groove, a discharging opening of the ore feeding groove is connected with a feeding opening of the electromagnetic classificator, and a tailing outlet of the electromagnetic classificator is connected with the tailing collecting groove to control material conveying and start and stop of stirring mechanisms in the ore feeding groove and the tailing collecting groove. According to the method, real prediction of the industrial indexes of the electromagnetic classificator is completed, the problem of poor concentrate grade indexes of the laboratory electromagnetic classificator is solved, an accurate basis is provided for special design and model selection of industrial large-scale equipment, and substandard mineral separation effect or investment loss caused by wrong specification and model selection can be avoided; debugging of dressing plant equipment is guided, the debugging period is shortened, and good industrial indexes are rapidly obtained.

The embodiment of the invention provides a wind power plant internal short-circuit current analytical calculation method and system, and belongs to the technical field of power system analysis. The method comprises the following steps: acquiring electrical topological data and operation state data of a wind power plant, and constructing a wind power plant equivalent network model based on the electrical topological data; constructing a wind turbine generator short-circuit injection model, and generating a short-circuit analysis model; preset short-circuit working condition parameters are obtained, a short-circuit working condition is applied to the short-circuit analytical model, short-circuit current is solved in an analytical calculation mode, and an initial short-circuit current analytical result is output; and correcting the wind turbine generator short-circuit injection model, performing analytical calculation on the short-circuit analytical model again under the constraint of the corrected wind turbine generator short-circuit injection model, and outputting a target short-circuit current analytical result. According to the method, an injection model correction mechanism based on an initial short-circuit current result is introduced into an analytic calculation framework, so that consistency analytic calculation of short-circuit current distribution and network equivalence relation of different electrical positions in the wind power plant is realized.

The invention relates to the technical field of circuit system analysis, in particular to a method, a system and equipment for measuring parasitic parameters of a high-frequency transformer. Voltage is applied to the primary side of the transformer, the secondary side is open-circuited, the secondary side voltage is measured, and the real part and the imaginary part of the ratio of the secondary side voltage to the power supply voltage are calculated; stopping power supply, measuring resistance and inductance of a primary side port, and obtaining magnetization inductance, magnetic core equivalent resistance, primary side leakage inductance and leakage resistance in combination with the ratio parameters; and opening the primary side, measuring the resistance and the inductance of the secondary side port, and calculating the leakage resistance and the leakage inductance of the secondary side by combining the measured parameters. Complex electrical connection is avoided, operation is easy and convenient, measurement errors are small, parasitic parameters of the transformer under different frequencies can be measured, and therefore the dynamic change rule of the parasitic parameters of the high-frequency transformer along with the frequencies is obtained.

This invention addresses the shortcomings of existing technologies by providing a method for parameter identification and SOH estimation of a first-order RC equivalent circuit model for automotive lithium batteries. The method includes the following steps: 1) Analysis of the principle of unknown parameter identification in chaotic systems; 2) Connecting electronic components such as load-controlled memristors as loads to the output of the first-order RC equivalent circuit model to establish a fourth-order chaotic system; 3) Analyzing the dynamic characteristics of the fourth-order chaotic system, including its phase trajectory diagram and time-domain waveform diagram; 4) Constructing an adaptive control law for the unknown parameters of the fourth-order chaotic system to achieve parameter identification and SOH estimation of the first-order RC equivalent circuit model. This invention's method exhibits high accuracy, stability, higher convergence speed, and stronger nonlinear prediction capabilities.

The invention discloses a power distribution network power electronic equipment broadband domain impedance characteristic test and stability evaluation method, a system, equipment and a medium, and relates to the technical field of power system analysis and power electronic equipment test, and the specific steps are as follows: injecting a controlled broadband disturbance signal at an access point of tested power distribution network power electronic equipment; the method comprises the steps of collecting voltage data and current data before and after disturbance, calculating equipment side impedance and power grid side impedance, evaluating single-equipment access stability by adopting a frequency domain stability analysis method, establishing a node admittance matrix to evaluate multi-equipment access stability, establishing an equipment impedance change trend calculation formula to calculate an equipment impedance change rate, and calculating the equipment impedance change rate. And outputting a comprehensive stability evaluation result of the power distribution network power electronic equipment. According to the method, broadband domain impedance online testing and stability evaluation of the power distribution network power electronic equipment under the actual operation working condition can be achieved, meanwhile, the trend that the equipment impedance changes along with time or the working condition can be recognized, and early warning is conducted for potential instability risks.

The invention relates to the field of power system equipment management, in particular to a power plant electrical equipment intelligent predictive maintenance and health management system which comprises an electrical equipment operation data acquisition module, a state monitoring module, a fault prediction module and an expert decision module. An equipment state manifold model is constructed in combination with a differential geometry theory, a geodesic evolution prediction system is utilized to analyze a state trajectory evolution trend, a potential fault type and failure time are identified through a critical region identification and specific point analysis system, and the core innovation lies in mapping an equipment state to a differential manifold space. Technical upgrading from linearity to nonlinearity, from point monitoring to trajectory analysis and from determinacy early warning to topological structure analysis is realized, and a scientific decision basis is provided for power plant electrical equipment management.

The invention relates to an inverter grid-connected parameter stability domain identification method and device based on bifurcation characteristics, and the method comprises the steps: building a generalized swing equation based on differential algebraic equations of different inverters; deducing a unified standard form and equivalent parameters suitable for bifurcation analysis; systematically analyzing boundary conditions of generalized saddle node bifurcation, Hopf bifurcation and homoclinic bifurcation, and constructing region division with different dynamic behaviors in a parameter space; and based on system balance points and manifold characteristics in different regions, and in combination with a Melnikov function analysis result, stability domains under inverter control parameters and electrical parameters are accurately identified. According to the method, a nonlinear dynamics principle is utilized, bifurcation boundary conditions of an inverter grid-connected system are deduced, typical areas with different dynamics structures in a parameter space are constructed, parameter stability domains under different operation working conditions are further identified, the multi-parameter stability problem of a complex system can be reduced to boundary judgment of a few key parameters, and the stability of the inverter grid-connected system is improved. And the stability domain identification efficiency and precision are greatly improved.

The invention discloses an electrical equipment energy efficiency energy-saving control system, which comprises an energy efficiency data acquisition module used for acquiring operation data of electrical equipment under multiple working conditions, constructing an energy efficiency characteristic association model, and generating independent energy efficiency characteristic information according to the energy efficiency characteristic association model; the system analysis module is used for analyzing an electrical system architecture, monitoring an equipment combination operation condition, obtaining dynamic operation data of electrical equipment and generating a combination independent characteristic; and the energy efficiency management and control scheme output module is used for updating the energy efficiency energy-saving simulation control process of the electrical equipment according to the combined independent characteristics in combination with the energy efficiency requirements and the independent energy efficiency characteristic information to obtain a combined energy efficiency energy-saving control scheme. According to the invention, comprehensive and accurate management and control of the energy efficiency of the electrical equipment are realized, the problems of incomplete data acquisition, poor system collaboration and rough management and control scheme in the prior art are solved, and the operation requirement of energy-saving control of the energy efficiency of the electrical equipment is met.

A method and system for detecting a fault traveling wave head of a power distribution network relates to the technical field of traveling wave detection, and the method comprises the steps: constructing a line topological graph for each section of a power distribution line and a connected distributed power supply, and representing electrical equipment comprising a load fluctuation balance unit and a traveling wave detection terminal in the line topological graph; when the distribution line runs, the distribution line distributed power supply switching time and the load fluctuation uniformity degree of each detection point are analyzed, and the type of each section is defined according to an analysis result; the data analysis frequency of the corresponding detection terminal is adjusted according to the type of each paragraph of the distribution line, and the condition that a single parameter in each paragraph exceeds a set value is independently processed; the detection result of the fault traveling wave signal is judged, if the wave head of the fault traveling wave signal is not captured or recognized after the fault occurs, the data analysis frequency of the system is improved, and the traveling wave head signal is analyzed by adopting an auxiliary judgment method. The method has the advantages of being accurate in detection and low in operation and maintenance cost.

The invention relates to the technical field of flywheel energy storage systems, in particular to a consistency control method and system for a distributed flywheel energy storage system, and the method comprises the following steps: based on the flywheel energy storage system, analyzing the power and change trend of an energy storage unit, discriminating a load signal, comparing the power and rotating speed of multiple units in real time, triggering synchronous adjustment, and compensating output difference. And finally, optimizing the response consistency to obtain a consistency adjustment reference. According to the invention, through dynamic comparison of power difference and rotation speed change, multi-unit operation states are brought into an overall determination view angle, dynamic synchronization of energy distribution and output targets is realized, and after units with low energy utilization are screened, target correction is automatically completed, so that the adjustment action is finer, and output current and rotation speed parameters are linked; a self-adaptive compensation mechanism is formed for power output offset, a dynamic cooperation relation of units in a global situation is formed, and after an adjustment action is finished, a self-adjustment and discrimination mechanism is improved through comparison of a response rate and a state.

The invention discloses a new energy limit scale evaluation method and system considering the influence of a conventional direct current system, and belongs to the technical field of new energy grid-connected scale evaluation of an alternating current and direct current hybrid system. The method comprises the following steps: respectively establishing a direct-current power transmission system analysis model and a new energy analysis model for a direct-current power transmission system of a power grid and reactive compensation equipment of a new energy station; according to the DC power transmission system analysis model, establishing a power grid equivalent model based on the DC power transmission system; and solving the grid-connected scale of the new energy limit for the new energy analysis model and the power grid equivalent model. The implementation of the invention is beneficial for power system planners to plan the new energy limit grid-connected scale according to the accessed direct current system.

The invention discloses a participation factor analysis method and a stability analysis method of an electric power system, and belongs to the technical field of electric power system analysis control, and the participation factor analysis method of the electric power system comprises the steps: calculating the state energy of each state of a linear period time-varying system after linearization of the electric power system; calculating modal energy of each mode in the linear period time-varying system; and finally, taking the ratio of the two as a participation factor corresponding to the kth mode lambda k and the ith state xi (t). According to the mode, the correlation degree between each mode and each state can be accurately described. The module value of each element in the finally obtained participation factor matrix of the linear periodic time-varying system can represent the correlation degree between the corresponding state and mode of the element in the linear periodic time-varying system, and the element with the larger module value represents the higher correlation degree between the corresponding state and mode. And a theoretical basis can be provided for subsequent stability analysis and system controller pre-design.

The invention provides a method for evaluating the influence of distributed power supply steady-state off-network on electric energy quality, and relates to the technical field of electric power system analysis. The evaluation method comprises the following steps: for a power system, if steady-state off-network occurs in a distributed power supply, constructing a feature vector according to basic operation data and state data of a corresponding off-network node; and taking the feature vector as an input, and calculating a voltage deviation and a harmonic total distortion rate through a power supply off-network-electric energy quality mapping function so as to evaluate the influence of steady-state off-network on the electric energy quality. According to the evaluation method, the corresponding electric energy quality index change can be quickly calculated according to different off-network conditions of the distributed power supply, so that the evaluation of the off-network electric energy quality influence of the distributed power supply in a steady state is realized.