Disclosure of Invention
Aiming at the defects of the prior art, the invention provides a data mining method and a data mining system for serving a micro-grid control system, and solves the problems in the background art.
The data mining system for the micro-grid control system comprises a data acquisition module, a feature extraction and abnormality assessment module, a fault positioning module, an equipment health monitoring module and an intelligent repairing module;
The data acquisition module is used for collecting related data of the micro-grid in real time and constructing a micro-grid data set S according to the collected related data of the micro-grid;
The feature extraction and anomaly evaluation module is used for preprocessing according to the micro-grid data set S, performing summarization calculation according to the preprocessed micro-grid data set S, acquiring a voltage stability factor S v (t), a frequency deviation factor S f (t) and a harmonic total distortion rate THD, acquiring a power quality comprehensive score Q elec according to the voltage stability factor S v (t), the frequency deviation factor S f (t) and the harmonic total distortion rate THD, presetting a power score threshold Q normal, performing comparison analysis on the power score threshold Q normal and the power quality comprehensive score Q elec, evaluating whether the micro-grid is faulty, if Q elec>Qnormal, indicating that the micro-grid is faulty, and triggering the fault positioning module;
The fault positioning module is used for setting a plurality of data monitoring points in the micro-grid, collecting voltage waveform data of the data monitoring points, determining the positions of fault points according to the traveling wave propagation principle, acquiring information of an energy storage battery and an inverter of a line where the fault points are located, and generating a fault point equipment set G;
The device health monitoring module is used for constructing an energy storage battery aging model and an inverter aging model by using a linear regression algorithm according to the micro-grid data set S and the power quality comprehensive score Q elec to obtain an energy storage battery aging rate And inverter burn-in rateThe energy storage battery health score SoH b (t) and the inverter health score R inv (t) are obtained through calculation, comprehensive calculation is carried out according to the energy storage battery health score SoH b (t) and the inverter health score R inv (t), and the residual use time RUL b of the energy storage battery and the residual use time RUL inv of the inverter are obtained;
The intelligent repairing module is used for obtaining the residual service time RUL b of the energy storage battery and the residual service time RUL inv of the inverter of the line where the fault point is located according to the fault point equipment set G, performing equipment screening to obtain standby equipment, obtaining an optimal fault repairing path P opt from the starting point of the standby equipment to the fault point by using Dijkstra shortest path algorithm, and performing fault repairing according to the optimal fault repairing path P opt.
Preferably, the data acquisition module is used for deploying a smart sensor group on a micro-grid, collecting related data of the micro-grid in real time, and constructing a micro-grid data set S according to the collected related data of the micro-grid, wherein the related data of the micro-grid comprises power quality data and equipment operation data;
the intelligent sensor group comprises a voltage monitor, a current monitor, a frequency detector, a thermal resistance temperature sensor and a power measuring instrument;
the power quality data includes a voltage V, a current I, and a power frequency f;
The device operating data includes a battery state of charge, SOC, energy storage battery load factor, L SOC, energy storage battery operating temperature, T b, inverter operating temperature, T inv, inverter load factor, L inv, and line transmit power, C current.
Preferably, the feature extraction and abnormality evaluation module comprises a feature extraction unit and an evaluation unit;
The feature extraction unit is used for preprocessing according to the micro-grid data set S, and acquiring a voltage stability factor S v (t), a frequency deviation factor S f (t) and a harmonic total distortion (THD) according to the preprocessed micro-grid data set S, wherein preprocessing comprises data cleaning, denoising and data standardization;
The voltage stability factor S v (t) is obtained by the following steps:
wherein T represents a sampling time window, V (θ) represents a voltage at a time point θ, V (θ+Δt) represents a voltage at a time point θ+Δt, θ ε [ T-T, T ], Δt represents a sampling time interval;
The frequency deviation factor S f (t) is obtained by the following steps:
Wherein f (θ) represents a grid frequency value at time θ, and f nom represents a grid standard frequency value;
According to the power quality data in the micro-grid data set S, performing frequency domain decomposition on the voltage V by using fast fourier transform, converting the voltage waveform in the time domain to the frequency domain to obtain a fundamental wave amplitude H 1 and a harmonic wave amplitude H n, and obtaining a harmonic total distortion rate THD according to the fundamental wave amplitude H 1 and the harmonic wave amplitude H n, wherein the specific obtaining mode of the harmonic wave amplitude H n is as follows:
Hn=n·H1;
wherein H 1 represents the fundamental wave amplitude and n represents the harmonic frequency;
the harmonic total distortion THD acquisition mode is as follows:
Wherein H n represents the harmonic amplitude, and n is more than or equal to 2.
Preferably, the evaluation unit is configured to perform summary calculation according to the voltage stability factor S v (t), the frequency deviation factor S f (t), and the harmonic total distortion ratio THD, to obtain a power quality comprehensive score Q elec, where the power quality comprehensive score Q elec is obtained by:
Qelec=α1·Sv(t)+α2·Sf(t)+α3·THD+C;
Wherein, α 1、α2 and α 3 respectively represent the weight coefficients of the voltage stability factor S v (t), the frequency deviation factor S f (t) and the harmonic total distortion THD, and C represents the first correction constant;
And presetting a power grading threshold Q normal, comparing and analyzing the power grading threshold Q normal with a power quality comprehensive grading Q elec, and evaluating whether the micro-grid fails, if Q elec≤Qnormal, the micro-grid does not fail without intervention, and if Q elec>Qnormal, the micro-grid fails, and triggering a fault positioning module to perform fault positioning on the micro-grid.
Preferably, the fault positioning module is used for setting a plurality of data monitoring points in the micro-grid, and collecting voltage waveform data of each data monitoring point in real time when the micro-grid fails, wherein the voltage waveform data refers to waveform change of a voltage signal;
According to the obtained voltage waveform data of each data monitoring point, two data monitoring points A and B with the largest amplitude variation of the voltage traveling wave signal are selected, the time difference delta t AB of the voltage traveling wave signal reaching the data monitoring points A and B is obtained, any one data monitoring point is randomly selected from the data monitoring points A and B according to the traveling wave propagation principle, and the distance d between any one data monitoring point in the data monitoring points A and B and the fault point is calculated, wherein the specific calculation mode is as follows:
Wherein v h represents the propagation speed of the traveling wave, and Δt AB represents the time difference between the traveling wave reaching the data monitoring point a and the data monitoring point B;
According to a micro-grid control system, a micro-grid topological graph is obtained, a data monitoring point A and a data monitoring point B are marked in the micro-grid topological graph, a line where a fault point is located in the micro-grid topological graph is positioned and the position of the fault point is marked by combining the distance d between any one of the data monitoring points A and B and the fault point, and energy storage battery data and inverter data of the line where the fault point is located are collected to generate a fault point equipment set G.
Preferably, the device health monitoring module comprises a device aging rate calculating unit and a health state analyzing unit;
the device aging rate calculation unit is configured to construct an energy storage battery aging model and an inverter aging model according to the fault point device set G, the micro-grid data set S and the power quality comprehensive score Q elec for the energy storage battery and the inverter of the line where the fault point is located, and the energy storage battery aging model has the following concrete expression form:
In the formula, Representing the aging rate of the energy storage battery at the current time point T, wherein Q elec (T) represents the comprehensive power quality score at the current time point T, T b (T) represents the running temperature of the energy storage battery at the current time point T, SOC (T) represents the battery charge state of the energy storage battery at the current time point T, and k 1、k2 and k 3 represent regression coefficients;
The inverter aging model has the following concrete expression form:
In the formula, Representing an inverter aging rate at a current time point T, L inv (T) representing an inverter load rate at the current time point T, T inv (T) representing an inverter operation temperature at the current time point T, and m 1、m2 and m 3 representing regression coefficients;
And collecting historical micro-grid operation data, dividing the historical micro-grid operation data into a training set and a testing set, inputting an energy storage battery aging model and an inverter aging model by using the training set for training, fitting parameters of the energy storage battery aging model and the inverter aging model by using a least square method to obtain regression coefficients k 1、k2、k3、m1、m2 and m 3, and verifying the energy storage battery aging model and the inverter aging model by using the testing set.
Preferably, the health state analysis unit is configured to obtain an aging rate of the energy storage battery according to the trained aging model of the energy storage battery and the trained aging model of the inverterAnd inverter burn-in rateAnd calculate the energy storage battery health score SoH b (t) and the inverter health score R inv (t), and obtain the remaining use time RUL b of the energy storage battery and the remaining use time RUL inv of the inverter, the energy storage battery health score SoH b (t) and the inverter health score R inv (t) are calculated as follows:
Where SoH b(t0) represents the energy storage battery health score at the initial time point t 0, R inv(t0) represents the inverter health score at the initial time point t 0, The rate of aging of the energy storage battery at time point tau is indicated,Inverter aging rate at time point τ, τ e [ t 0, t ];
The energy storage battery remaining use time RUL b and the inverter remaining use time RUL inv are obtained by the following steps:
Where SoH b,critical represents the energy storage battery health score threshold and R inv,max represents the inverter health score maximum.
Preferably, the intelligent repair module comprises a path planning unit and a fault repair unit;
the path planning unit is configured to obtain an optimal fault repair path P opt according to a microgrid topology map by using a path planning algorithm, where a specific obtaining manner of the optimal fault repair path P opt is as follows:
According to the health equipment monitoring module and the micro-grid data set S, operation data of the energy storage battery and the inverter are obtained, wherein the operation data comprise residual use time RUL b of the energy storage battery, residual use time RUL inv of the inverter, load rate L SOC of the energy storage battery, load rate L inv of the inverter, health score SoH b (t) of the energy storage battery and health score R inv (t) of the inverter;
Converting the micro-grid topological graph into a micro-grid weighted graph F, wherein the micro-grid weighted graph F has the following concrete expression form:
F=(N,E);
N represents nodes in the micro-grid, wherein the nodes comprise an energy storage battery, an inverter and load nodes, E represents edges, and the edges comprise connecting lines among the nodes, wherein the load nodes refer to power consumption ends, namely electric equipment needing power supply and an electric area;
According to the microgrid weighting graph F, for each energy storage battery and inverter, a preset energy storage battery usage time health threshold T (RUL b)min and inverter usage time health threshold T (RUL inv)min, and according to the remaining energy storage battery usage time RUL b and inverter usage time RUL inv, in combination with the preset energy storage battery usage time health threshold T (RUL b)min and inverter usage time health threshold T (RUL inv)min, energy storage battery and inverter screening is performed, and the energy storage batteries and inverters of RUL b>T(RULb)min and RUL inv>T(RULinv)min are reserved as standby devices);
According to the operation data of the energy storage battery and the inverter, calculating the weight of each side, wherein the specific calculation process comprises the following steps:
Wherein RUL b,i represents the remaining use time of the energy storage battery of the node i, RUL inv,i represents the remaining use time of the inverter of the node i, L SOC,i represents the load factor of the energy storage battery of the node i, L inv,i represents the load factor of the inverter of the node i, C remaining,ij represents the remaining transmission capacity of the line between the node i and the node j, and beta, gamma, delta, epsilon and epsilon represent weight coefficients;
Using Dijkstra shortest path algorithm, taking a micro-grid weighted graph G as input, carrying out path search, setting a path search target as minimum path total weight, and selecting a path with the minimum path total weight as an optimal fault restoration path P opt, wherein the minimum path total weight has the concrete expression form:
Where W path represents the total weight of path P and e ij represents the edge from node i to node j.
Preferably, the fault repairing unit is configured to perform a fault repairing operation according to the optimal fault repairing path P opt, where the optimal fault repairing path P opt includes a start point device, a pass line and an end point load, the fault repairing operation includes initializing a repairing task, starting a standby device and switching the line, and monitoring related data of the micro grid after the fault repairing operation in real time.
A data mining method for a micro grid control system, comprising the steps of,
Step one, collecting related data of a micro-grid in real time, and constructing a micro-grid data set S according to the collected related data of the micro-grid;
step two, preprocessing is carried out according to the micro-grid data set S, summarizing calculation is carried out according to the preprocessed micro-grid data set S, a voltage stability factor S v (t), a frequency deviation factor S f (t) and a harmonic total distortion THD are obtained, a power quality comprehensive score Q elec is obtained according to the voltage stability factor S v (t), the frequency deviation factor S f (t) and the harmonic total distortion THD, a power quality comprehensive score Q normal is preset, a power score threshold Q normal and a power quality comprehensive score Q elec are compared and analyzed, whether the micro-grid fails is evaluated, if Q elec>Qnormal is judged, the micro-grid fails is indicated, and a fault positioning module is triggered at the moment;
Setting a plurality of data monitoring points in the micro-grid, collecting voltage waveform data of the data monitoring points, determining fault point positions according to a traveling wave propagation principle, acquiring information of an energy storage battery and an inverter of a line where the fault points are located, and generating a fault point equipment set G;
Fourth, according to the micro-grid data set S and the power quality comprehensive score Q elec, an energy storage battery aging model and an inverter aging model are built by using a linear regression algorithm, and an energy storage battery aging rate is obtained And inverter burn-in rateThe energy storage battery health score SoH b (t) and the inverter health score R inv (t) are obtained through calculation, comprehensive calculation is carried out according to the energy storage battery health score SoH b (t) and the inverter health score R inv (t), and the residual use time RUL b of the energy storage battery and the residual use time RUL inv of the inverter are obtained;
Step five, according to the fault point device set G, obtaining the remaining service time RUL b of the energy storage battery and the remaining service time RUL inv of the inverter of the line where the fault point is located, performing device screening to obtain the standby device, obtaining an optimal fault repairing path P opt from the starting point of the standby device to the fault point by using Dijkstra shortest path algorithm, and performing fault repairing according to the optimal fault repairing path P opt.
The invention provides a data mining method and a system for serving a micro-grid control system, which have the following beneficial effects:
(1) Through the feature extraction and anomaly evaluation module, the voltage stability factor S v (t), the frequency deviation factor S f (t) and the harmonic total distortion rate THD in the micro-grid are collected and analyzed in real time, the comprehensive power quality score Q elec is comprehensively calculated, the power score threshold Q normal is set, the anomaly state of the micro-grid can be timely found, and compared with a traditional single power quality monitoring mode, the method is based on multi-factor comprehensive evaluation, has higher accuracy and instantaneity, is beneficial to quickly identifying the power fluctuation anomaly condition, and accordingly improves the overall operation stability and power supply quality of the micro-grid.
(2) Through the collaborative work of the fault locating module and the equipment health monitoring module, fault points in the micro-grid can be located rapidly, accurate assessment on equipment states is achieved based on operation data of the energy storage battery and the inverter, such as aging rate, health score and residual service time.
(3) Through the intelligent repair module, the system can generate an optimal fault repair path P opt by combining a micro-grid topological graph, energy storage battery operation data and inverter operation data based on equipment information of a fault point after the fault occurs, and compared with the traditional manual repair scheme, the system optimizes the selection and line switching process of standby equipment on the basis of considering the residual use time RUL b of the energy storage battery, the residual use time RUL inv of the inverter, the load rate L SOC of the energy storage battery, the load rate L inv of the inverter and the line transmission power C current.
Detailed Description
The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
Example 1
Referring to fig. 1, the invention provides a data mining system serving a micro-grid control system, which comprises a data acquisition module, a feature extraction and abnormality evaluation module, a fault positioning module, an equipment health monitoring module and an intelligent repair module;
The data acquisition module is used for collecting related data of the micro-grid in real time and constructing a micro-grid data set S according to the collected related data of the micro-grid;
The feature extraction and anomaly evaluation module is used for preprocessing according to the micro-grid data set S, performing summarization calculation according to the preprocessed micro-grid data set S, acquiring a voltage stability factor S v (t), a frequency deviation factor S f (t) and a harmonic total distortion rate THD, acquiring a power quality comprehensive score Q elec according to the voltage stability factor S v (t), the frequency deviation factor S f (t) and the harmonic total distortion rate THD, presetting a power score threshold Q normal, performing comparison analysis on the power score threshold Q normal and the power quality comprehensive score Q elec, evaluating whether the micro-grid is faulty, if Q elec>Qnormal, indicating that the micro-grid is faulty, and triggering the fault positioning module;
The fault positioning module is used for setting a plurality of data monitoring points in the micro-grid, collecting voltage waveform data of the data monitoring points, determining the positions of fault points according to the traveling wave propagation principle, acquiring information of an energy storage battery and an inverter of a line where the fault points are located, and generating a fault point equipment set G;
The device health monitoring module is used for constructing an energy storage battery aging model and an inverter aging model by using a linear regression algorithm according to the micro-grid data set S and the power quality comprehensive score Q elec to obtain an energy storage battery aging rate And inverter burn-in rateThe energy storage battery health score SoH b (t) and the inverter health score R inv (t) are obtained through calculation, comprehensive calculation is carried out according to the energy storage battery health score SoH b (t) and the inverter health score R inv (t), and the residual use time RUL b of the energy storage battery and the residual use time RUL inv of the inverter are obtained;
The intelligent repairing module is used for obtaining the residual service time RUL b of the energy storage battery and the residual service time RUL inv of the inverter of the line where the fault point is located according to the fault point equipment set G, performing equipment screening to obtain standby equipment, obtaining an optimal fault repairing path P opt from the starting point of the standby equipment to the fault point by using Dijkstra shortest path algorithm, and performing fault repairing according to the optimal fault repairing path P opt.
In the embodiment, the data acquisition module is used for collecting the power quality data, the equipment operation data and the environment data of the micro-grid in real time, the micro-grid data set S is constructed, comprehensive and accurate data support is provided for subsequent analysis, the feature extraction and anomaly evaluation module can be used for obtaining the voltage stability factor S v (t), the frequency deviation factor S f (t) and the total harmonic distortion THD, calculating the power quality comprehensive score Q elec, accurately evaluating the power quality state of the micro-grid, rapidly identifying abnormal conditions, the fault positioning module is used for combining the traveling wave propagation principle, rapidly positioning fault points and obtaining relevant equipment data, generating the fault point equipment set G, shortening the fault response time, the equipment health monitoring module is used for providing scientific basis for optimizing equipment management and maintenance based on the aging rate model of the energy storage battery and the inverter, the equipment health state is dynamically evaluated, the equipment residual service time is predicted, the intelligent repair module is used for combining the micro-grid topological graph and the equipment health state data, the standby equipment is screened and the optimal fault repair path P opt is obtained by using the Dijkstra shortest path algorithm, the service life and load capacity of the equipment are guaranteed to be prioritized in the repair process, the service life and the load capacity is improved, the fault stability and the service life of the fault can be improved, the fault can be continuously and the fault operation can be guaranteed, the fault is prolonged and the fault is continuously can be continuously and prolonged.
Example 2
Referring to fig. 1, the data acquisition module is specifically configured to deploy an intelligent sensor group on a micro-grid, collect micro-grid related data in real time, and construct a micro-grid data set S according to the collected micro-grid related data, where the micro-grid related data includes power quality data and equipment operation data;
the intelligent sensor group comprises a voltage monitor, a current monitor, a frequency detector, a thermal resistance temperature sensor and a power measuring instrument;
the power quality data includes a voltage V, a current I, and a power frequency f;
The equipment operation data comprise battery charge state SOC of the energy storage battery, load rate L SOC of the energy storage battery, operation temperature T b of the energy storage battery, operation temperature T inv of the inverter, load rate L inv of the inverter and line transmission power C current;
The voltage V is obtained through a voltage monitor;
the current I is obtained through a current monitor;
The power frequency f is obtained through a frequency detector;
The battery charge state SOC of the energy storage battery, the load rate L SOC of the energy storage battery and the running temperature T b of the energy storage battery are obtained through a battery management system BMS;
The inverter running temperature T inv is obtained through a thermal resistance temperature sensor;
The inverter load factor L inv and the line transmission power C current are obtained by a power meter.
In the embodiment, through disposing the intelligent sensor group on the micro-grid, the system can acquire power quality data such as voltage V, current I, power frequency f and equipment operation data such as battery charge state SOC of the energy storage battery, energy storage battery load rate L SOC, energy storage battery operation temperature T b, inverter operation temperature T inv, inverter load rate L inv and line transmission power C current in real time, the accurate collection and integration of the multi-source data construct a comprehensive micro-grid data set S, high-quality basic data support is provided for subsequent data analysis and optimization scheduling, compared with a traditional single-parameter monitoring mode, the intelligent sensor group can capture dynamic changes in the micro-grid operation in real time, high efficiency and multiple dimensions, ensure that the system can respond to power grid abnormality or equipment operation deviation in time, through comprehensive data collection, the system can evaluate power quality problems and equipment health status more accurately, the monitoring accuracy and operation stability of the micro-grid are effectively improved, intelligent management and optimization basis of power supply are laid, fault occurrence rate and maintenance cost are reduced, and reliability and sustainability of the system are enhanced.
Example 3
Referring to fig. 1, the feature extraction and anomaly evaluation module includes a feature extraction unit and an evaluation unit;
The feature extraction unit is used for preprocessing according to the micro-grid data set S, and acquiring a voltage stability factor S v (t), a frequency deviation factor S f (t) and a harmonic total distortion (THD) according to the preprocessed micro-grid data set S, wherein preprocessing comprises data cleaning, denoising and data standardization;
The voltage stability factor S v (t) is obtained by the following steps:
Wherein T represents a sampling time window, V (theta) represents a voltage at a time point theta, V (theta+delta T) represents a voltage at a time point theta+delta T, theta epsilon [ T-T, T ] delta T represents a sampling time interval, and the larger the value of S v (T) is, the more severe the voltage fluctuation is, and the worse the stability of the power grid is;
The frequency deviation factor S f (t) is obtained by the following steps:
Wherein f (θ) represents a grid frequency value at time θ, f nom represents a grid standard frequency value, and the more the frequency deviation factor S f (t) tends to zero, the more stable the grid frequency is;
The power grid standard frequency value f nom is obtained through a national power grid operation standard table;
According to the power quality data in the micro-grid data set S, performing frequency domain decomposition on the voltage V by using fast fourier transform, converting the voltage waveform in the time domain to the frequency domain to obtain a fundamental wave amplitude H 1 and a harmonic wave amplitude H n, and obtaining a harmonic total distortion rate THD according to the fundamental wave amplitude H 1 and the harmonic wave amplitude H n, wherein the specific obtaining mode of the harmonic wave amplitude H n is as follows:
Hn=n·H1;
wherein H 1 represents the fundamental wave amplitude and n represents the harmonic frequency;
the fundamental wave amplitude H 1 refers to the sine wave component with the lowest frequency in the voltage signal, namely the nominal frequency of the power system;
The harmonic amplitude H n refers to a sine wave component of an integral multiple frequency component of the fundamental wave frequency, is a waveform distortion component introduced by nonlinear load and use of power electronic equipment, and is an integral multiple of the fundamental wave amplitude;
the harmonic total distortion THD acquisition mode is as follows:
Wherein H n represents the harmonic amplitude, and n is more than or equal to 2.
The evaluation unit is configured to perform summary calculation according to the voltage stability factor S v (t), the frequency deviation factor S f (t), and the harmonic total distortion ratio THD, and obtain an electric power quality comprehensive score Q elec, where an electric power quality comprehensive score Q elec is obtained by:
Qelec=α1·Sv(t)+α2·Sf(t)+α3·THD+C;
Wherein, α 1、α2 and α 3 respectively represent the weight coefficients of the voltage stability factor S v (t), the frequency deviation factor S f (t) and the harmonic total distortion THD, and C represents the first correction constant, wherein, the value of the weight coefficient is set by the customer according to the actual situation, and 0< α 1<1,0<α2<1,0<α3<1,α1+α2+α3 =1;
And presetting a power grading threshold Q normal, comparing and analyzing the power grading threshold Q normal with a power quality comprehensive grading Q elec, and evaluating whether the micro-grid fails, if Q elec≤Qnormal, the micro-grid does not fail without intervention, and if Q elec>Qnormal, the micro-grid fails, and triggering a fault positioning module to perform fault positioning on the micro-grid.
In the embodiment, the voltage stability factor S v (t), the frequency deviation factor S f (t) and the harmonic total distortion rate THD are extracted by preprocessing the micro-grid data set S and according to the preprocessed micro-grid data set S, the dynamic change characteristics of the power quality can be comprehensively reflected, in addition, the fundamental wave amplitude H 1 and the harmonic wave amplitude H n of the voltage V are extracted by using fast fourier transformation, so that the harmonic total distortion rate THD is calculated, nonlinear loads and harmonic distortion caused by power electronic equipment can be effectively captured, the evaluation unit generates the power quality comprehensive score Q elec by summarizing the voltage stability factor S v (t), the frequency deviation factor S f (t) and the harmonic total distortion rate THD, and compares the power quality comprehensive score Q elec with a preset power score threshold Q normal.
Example 4
Referring to fig. 1, the fault location module is specifically configured to set a plurality of data monitoring points in the micro-grid, and collect voltage waveform data of each data monitoring point in real time when the micro-grid fails, where the voltage waveform data refers to waveform variation of a voltage signal;
According to the obtained voltage waveform data of each data monitoring point, two data monitoring points A and B with the largest amplitude variation of the voltage traveling wave signal are selected, the time difference delta t AB of the voltage traveling wave signal reaching the data monitoring points A and B is obtained, any one data monitoring point is randomly selected from the data monitoring points A and B according to the traveling wave propagation principle, and the distance d between any one data monitoring point in the data monitoring points A and B and the fault point is calculated, wherein the specific calculation mode is as follows:
Wherein v h represents the propagation speed of the traveling wave, and Δt AB represents the time difference between the traveling wave reaching the data monitoring point a and the data monitoring point B;
According to a micro-grid control system, a micro-grid topological graph is obtained, a data monitoring point A and a data monitoring point B are marked in the micro-grid topological graph, a line where a fault point is located in the micro-grid topological graph is positioned and the position of the fault point is marked by combining the distance d between any one of the data monitoring points A and B and the fault point, and energy storage battery data and inverter data of the line where the fault point is located are collected to generate a fault point equipment set G.
In the embodiment, through real-time monitoring and accurate analysis of the fault positioning module, the positioning efficiency and accuracy of the micro-grid when faults occur can be effectively improved, firstly, the fault positioning module sets a plurality of data monitoring points, acquires voltage waveform data, can rapidly capture the propagation characteristics of traveling wave signals when the faults occur, so that key monitoring points are selected through amplitude changes, the distance between the fault points and the monitoring points is calculated based on traveling wave propagation principles, compared with the traditional manual investigation and single-point monitoring mode, the method not only improves the fault positioning speed, but also reduces the misjudgment rate, and secondly, through combination with a micro-grid topological graph, the fault points can be accurately mapped to specific line positions, and further related line equipment such as an energy storage battery and an inverter can be obtained, so that a fault point equipment set G is generated, and the multi-dimensional analysis mode combining the power waveform data and equipment operation information can comprehensively evaluate the fault influence range, thereby providing accurate data support for subsequent health monitoring and repairing path planning, finally, the application of the module shortens the fault response time, improves the reliability and stability of the micro-grid operation, and reduces the damage caused by the power supply delay range.
Example 5
Referring to fig. 1, specifically, the device health monitoring module includes a device aging rate calculating unit and a health status analyzing unit;
the device aging rate calculation unit is configured to construct an energy storage battery aging model and an inverter aging model according to the fault point device set G, the micro-grid data set S and the power quality comprehensive score Q elec for the energy storage battery and the inverter of the line where the fault point is located, and the energy storage battery aging model has the following concrete expression form:
In the formula, Representing the aging rate of the energy storage battery at the current time point T, wherein Q elec (T) represents the comprehensive power quality score at the current time point T, T b (T) represents the running temperature of the energy storage battery at the current time point T, SOC (T) represents the battery charge state of the energy storage battery at the current time point T, and k 1、k2 and k 3 represent regression coefficients;
The inverter aging model has the following concrete expression form:
In the formula, Representing an inverter aging rate at a current time point T, L inv (T) representing an inverter load rate at the current time point T, T inv (T) representing an inverter operation temperature at the current time point T, and m 1、m2 and m 3 representing regression coefficients;
And collecting historical micro-grid operation data, dividing the historical micro-grid operation data into a training set and a testing set, inputting an energy storage battery aging model and an inverter aging model by using the training set for training, fitting parameters of the energy storage battery aging model and the inverter aging model by using a least square method to obtain regression coefficients k 1、k2、k3、m1、m2 and m 3, and verifying the energy storage battery aging model and the inverter aging model by using the testing set.
The health state analysis unit is used for obtaining the aging rate of the energy storage battery according to the trained aging model of the energy storage battery and the trained aging model of the inverterAnd inverter burn-in rateAnd calculate the energy storage battery health score SoH b (t) and the inverter health score R inv (t), and obtain the remaining use time RUL b of the energy storage battery and the remaining use time RUL inv of the inverter, the energy storage battery health score SoH b (t) and the inverter health score R inv (t) are calculated as follows:
Where SoH b(t0) represents the energy storage battery health score at the initial time point t 0, R inv(t0) represents the inverter health score at the initial time point t 0, The rate of aging of the energy storage battery at time point tau is indicated,Inverter aging rate at time point τ, τ e [ t 0, t ];
The energy storage battery remaining use time RUL b and the inverter remaining use time RUL inv are obtained by the following steps:
Where SoH b,critical represents the energy storage battery health score threshold and R inv,max represents the inverter health score maximum.
The energy storage battery health score critical value SoH b,critical is obtained through manufacturing trademark data, and the inverter health score maximum value R inv,max is set to 1.
In the embodiment, through the cooperative work of the equipment aging rate calculation unit and the health state analysis unit, the operation safety of the micro-grid and the precision of equipment maintenance are improved, firstly, an aging model of an energy storage battery and an inverter is built through a linear regression algorithm, the aging rate of equipment under different operation conditions can be dynamically quantified, the dynamic analysis method breaks through the limitation of traditional static evaluation, so that the change of the health state of the equipment can be captured in real time, and secondly, the aging rate of the energy storage battery is utilized through the health state analysis unitAnd inverter burn-in rateThe method for dynamically monitoring the health state of the micro-grid based on the health score and the residual life provides reliable basis for accurate maintenance and scheduling of the energy storage battery and the inverter, effectively avoids sudden faults caused by deterioration of the health state of the micro-grid, and in addition, the scheduling strategy of the micro-grid is optimized by combining the health data of the equipment, so that the equipment with good health state can be preferentially used under the power fluctuation scene, the equipment load is lightened, the service life of the equipment is prolonged, and in sum, the module can effectively reduce the operation cost of the micro-grid through accurate health monitoring and life assessment, improve the power supply stability, provide timely and scientific data support for fault restoration, and be a key guarantee for efficient and safe operation of the micro-grid.
Example 6
Referring to fig. 1, specifically, the intelligent repair module includes a path planning unit and a fault repair unit;
the path planning unit is configured to obtain an optimal fault repair path P opt according to a microgrid topology map by using a path planning algorithm, where a specific obtaining manner of the optimal fault repair path P opt is as follows:
According to the health equipment monitoring module and the micro-grid data set S, operation data of the energy storage battery and the inverter are obtained, wherein the operation data comprise residual use time RUL b of the energy storage battery, residual use time RUL inv of the inverter, load rate L SOC of the energy storage battery, load rate L inv of the inverter, health score SoH b (t) of the energy storage battery and health score R inv (t) of the inverter;
Converting the micro-grid topological graph into a micro-grid weighted graph F, wherein the micro-grid weighted graph F has the following concrete expression form:
F=(N,E);
N represents nodes in the micro-grid, wherein the nodes comprise an energy storage battery, an inverter and load nodes, E represents edges, and the edges comprise connecting lines among the nodes, wherein the load nodes refer to power consumption ends, namely electric equipment needing power supply and an electric area;
According to the microgrid weighting graph F, for each energy storage battery and inverter, a preset energy storage battery usage time health threshold T (RUL b)min and inverter usage time health threshold T (RUL inv)min, and according to the remaining energy storage battery usage time RUL b and inverter usage time RUL inv, in combination with the preset energy storage battery usage time health threshold T (RUL b)min and inverter usage time health threshold T (RUL inv)min, energy storage battery and inverter screening is performed, and the energy storage batteries and inverters of RUL b>T(RULb)min and RUL inv>T(RULinv)min are reserved as standby devices);
According to the operation data of the energy storage battery and the inverter, calculating the weight of each side, wherein the specific calculation process comprises the following steps:
Wherein RUL b,i represents the remaining usage time of the energy storage battery of the node i, RUL inv,i represents the remaining usage time of the inverter of the node i, L SOC,i represents the load factor of the energy storage battery of the node i, L inv,i represents the load factor of the inverter of the node i, C remaining,ij represents the remaining transmission capacity of the line between the node i and the node j, wherein the remaining transmission power C remaining,ij of the line between the node i and the node j is obtained by subtracting the transmission power C current of the line from the maximum transmission power C current,max of the line, β, γ, δ, ε and e represent weight coefficients, the data of which are set by the client according to the specific situation, 0< β <1,0< γ <1,0< δ <1,0< ε <1, β+γ+δ+ε=1;
Using Dijkstra shortest path algorithm, taking a micro-grid weighted graph G as input, carrying out path search, setting a path search target as minimum path total weight, and selecting a path with the minimum path total weight as an optimal fault restoration path P opt, wherein the minimum path total weight has the concrete expression form:
Where W path represents the total weight of path P and e ij represents the edge from node i to node j.
The fault repairing unit is configured to execute a fault repairing operation according to the optimal fault repairing path P opt, where the optimal fault repairing path P opt includes a start point device, a pass line and an end point load, the fault repairing operation includes initializing a repairing task, starting a standby device and switching the line, and monitors related data of the micro grid after the fault repairing operation in real time.
In the embodiment, through the cooperative work of the path planning unit and the fault repairing unit, the scheme can quickly generate the optimal fault repairing path P opt after the micro-grid fault occurs and efficiently execute repairing tasks, effectively improve the running reliability and repairing efficiency of the micro-grid, the path planning unit combines a health equipment monitoring module and a micro-grid data set S, acquires the residual service time RUL b of an energy storage battery, the residual service time RUL inv of an inverter, the load rate L SOC of the energy storage battery, the load rate L inv of the inverter, the health score SoH b (t) of the energy storage battery and the health score R inv (t) of the inverter, generates a micro-grid weighting graph F based on a micro-grid topological graph, and calculates the weight of each side by screening the energy storage equipment and the inverter with good health status as standby equipment, comprehensively considering factors such as equipment health state, load rate, line residual transmission capacity and the like, ensuring scientificity and high efficiency of repair path selection, finally using Dijkstra shortest path algorithm, taking the total weight of a minimized path as a target, selecting an optimal fault repair path P opt from a standby device to a fault point, executing repair operation by a fault repair unit according to the optimal fault repair path P opt, monitoring fault repair effect in real time, ensuring normal operation of a system, dynamically optimizing the repair path by a path planning algorithm, fully considering equipment health condition and line load condition, avoiding occurrence of repeated faults, improving repair efficiency, reducing extra burden of the standby device, simultaneously reducing influence of fault repair on integral operation of a power grid, the safety and stability of the micro-grid are guaranteed.
Referring to fig. 2, in particular, a data mining method for serving a micro grid control system, includes the steps of,
Step one, collecting related data of a micro-grid in real time, and constructing a micro-grid data set S according to the collected related data of the micro-grid;
step two, preprocessing is carried out according to the micro-grid data set S, summarizing calculation is carried out according to the preprocessed micro-grid data set S, a voltage stability factor S v (t), a frequency deviation factor S f (t) and a harmonic total distortion THD are obtained, a power quality comprehensive score Q elec is obtained according to the voltage stability factor S v (t), the frequency deviation factor S f (t) and the harmonic total distortion THD, a power quality comprehensive score Q normal is preset, a power score threshold Q normal and a power quality comprehensive score Q elec are compared and analyzed, whether the micro-grid fails is evaluated, if Q elec>Qnormal is judged, the micro-grid fails is indicated, and a fault positioning module is triggered at the moment;
Setting a plurality of data monitoring points in the micro-grid, collecting voltage waveform data of the data monitoring points, determining fault point positions according to a traveling wave propagation principle, acquiring information of an energy storage battery and an inverter of a line where the fault points are located, and generating a fault point equipment set G;
Fourth, according to the micro-grid data set S and the power quality comprehensive score Q elec, an energy storage battery aging model and an inverter aging model are built by using a linear regression algorithm, and an energy storage battery aging rate is obtained And inverter burn-in rateThe energy storage battery health score SoH b (t) and the inverter health score R inv (t) are obtained through calculation, comprehensive calculation is carried out according to the energy storage battery health score SoH b (t) and the inverter health score R inv (t), and the residual use time RUL b of the energy storage battery and the residual use time RUL inv of the inverter are obtained;
Step five, according to the fault point device set G, obtaining the remaining service time RUL b of the energy storage battery and the remaining service time RUL inv of the inverter of the line where the fault point is located, performing device screening to obtain the standby device, obtaining an optimal fault repairing path P opt from the starting point of the standby device to the fault point by using Dijkstra shortest path algorithm, and performing fault repairing according to the optimal fault repairing path P opt.
In the embodiment, the micro-grid data set S is constructed by collecting related data of the micro-grid in real time, comprehensive diagnosis and optimal scheduling of power quality and equipment health status are achieved, in power quality assessment, voltage stability factor S v (t), frequency deviation factor S f (t) and harmonic total distortion rate THD are utilized, multi-factor joint analysis is carried out, power quality comprehensive score Q elec is obtained, abnormal conditions of the micro-grid are accurately detected, traveling wave propagation principles are adopted for fault location problems, fault point positions are rapidly determined, fault point equipment information is obtained by combining a micro-grid topological graph, a foundation is laid for follow-up health status analysis and path planning, residual service time RUL b of an energy storage battery and residual service time RUL inv of the inverter are dynamically obtained through ageing model and health status prediction of the energy storage battery, and in fault restoration, the optimal fault restoration path P opt is generated through Dijkstra shortest path algorithm.
Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made therein without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.