Distributed power quality monitoring system

Abstract

The invention relates to the technical field of power systems, in particular to a distributed power quality monitoring system. Comprising a quality monitoring module which is arranged at each node in a power grid and collects electric energy quality parameters of each node in the power grid; the communication network module is connected with the quality monitoring module and is used for transmitting the acquired electric energy quality parameters; the central monitoring module is connected with the communication network module and is used for receiving, processing and storing data transmitted by monitoring equipment; the processing and analyzing module is connected with the central monitoring module and is used for performing electric energy quality analysis on the processed data; the alarm feedback module is connected with the processing and analyzing module and is used for sending out an alarm signal in time according to an analysis result and providing problem description and suggestions; according to the invention, a distributed remote monitoring mode of automatic detection and analysis is adopted, so that people do not need to present for detection; and each node is predicted by acquiring the central node, so that the data transmission quantity in unit time is reduced, and data transmission congestion is avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of power systems, and in particular to a distributed power quality monitoring system. Background Art

[0002] In modern production, electricity, as the main energy source, has an important attribute, namely, quality, like any other tangible product. In many industrial enterprises, such as steel enterprises, the high-power electrical equipment used generates a large amount of high-order harmonics, spike pulses and other power pollution, which has seriously endangered the quality of electricity. On the other hand, the large-scale use of precision electronic equipment and computer control systems have put forward more stringent requirements on the quality of electricity. This contradiction is becoming increasingly acute and has attracted great attention from the majority of technical personnel. The traditional way to monitor the quality of electricity is manual meter reading, which uses advanced portable measuring instruments for statistics and evaluation. However, it is labor-intensive, inefficient, and has large errors, and cannot meet current needs. For this reason, the prior art provides an online monitoring system, which sets nodes, installs detection equipment on the nodes, and evaluates the quality of electricity by receiving the detection data of the detection equipment. However, the prior art has a complicated process for evaluating the quality of electricity, which easily causes data blockage when there are too many nodes, thereby reducing the monitoring efficiency.

[0003] Therefore, how to provide a distributed power quality monitoring system that can achieve remote monitoring and avoid data congestion and increase monitoring efficiency has become a technical solution to be solved in this technical field. Summary of the invention

[0004] In view of the above problems existing in the prior art, the present invention is proposed.

[0005] To solve the above technical problems, the present invention provides the following technical solutions: a distributed power quality monitoring system, comprising: a quality monitoring module, arranged at each node in the power grid, for collecting power quality parameters of each node in the power grid;

[0006] A communication network module, connected to the quality monitoring module, for transmitting the collected power quality parameters;

[0007] A central monitoring module, connected to the communication network module, for receiving, processing and storing data transmitted by the monitoring equipment;

[0008] A processing and analysis module, connected to the central monitoring module, for performing power quality analysis and power quality prediction on the processed data;

[0009] The alarm feedback module is connected to the processing and analysis module and is used to issue an alarm signal in a timely manner and provide problem descriptions and suggestions based on the analysis results and prediction results.

[0010] As a preferred solution of a distributed power quality monitoring system described in the present invention, the quality monitoring module includes:

[0011] A voltage detection unit is provided at each node in the power grid and is used to detect the voltage data of each node in real time;

[0012] A current detection unit is provided at each node in the power grid and is used to detect the three-phase current data of each node in real time;

[0013] The frequency detection unit is arranged at each node in the power grid and is used to detect the frequency data of each node in real time.

[0014] As a preferred solution of a distributed power quality monitoring system described in the present invention, the quality monitoring module further includes:

[0015] A positioning unit is connected to the voltage detection unit, the current detection unit and the frequency detection unit; the positioning unit obtains the node position information of each detection unit, and generates a path-node model according to the path series node position information of each circuit in the power grid.

[0016] As a preferred solution of a distributed power quality monitoring system described in the present invention, the communication network module includes:

[0017] a collating unit, connected to the voltage detection unit, the current detection unit, the frequency detection unit and the positioning unit, and configured to insert the voltage data, the three-phase current data and the frequency data of the same node into corresponding positions in the path-node model to generate a path-node-parameter model carrying power quality parameters;

[0018] A wireless communication unit is connected to the collating unit and is used for wirelessly transmitting the path-node-parameter model.

[0019] As a preferred solution of a distributed power quality monitoring system described in the present invention, wherein: the central monitoring module includes:

[0020] a data receiving unit, connected to the wireless communication unit, and configured to periodically receive the path-node-parameter model;

[0021] A preprocessing unit connected to the data receiving unit, for preprocessing the power quality parameters carried by each node in the path-node-parameter model; the preprocessing process includes drawing a voltage fluctuation curve, a frequency fluctuation curve, summarizing three-phase current values ​​and calculating the average value of the three-phase current;

[0022] A storage unit connected to the preprocessing unit and used to store the voltage fluctuation curve, the frequency fluctuation curve, the three-phase current values ​​and the three-phase current average values ​​in a database;

[0023] A classification unit is connected to the storage unit and is used to organize the voltage fluctuation curve, frequency fluctuation curve, three-phase current value and three-phase current average value of the same node in the database into the same data set, and set the data set name to the node location information and the time information of obtaining the data.

[0024] As a preferred solution of a distributed power quality monitoring system described in the present invention, the processing and analysis module includes:

[0025] A data search unit connected to the storage unit; the data search unit searches the database for a data set of each node closest to the current time value according to the current time value, and obtains the voltage fluctuation curve, frequency fluctuation curve, three-phase current value and three-phase current average value in the set;

[0026] A fluctuation analysis unit connected to the data search unit; the fluctuation analysis unit sequentially obtains the voltage fluctuation curve and the frequency fluctuation curve, and identifies the amplitude change value at each time in each curve; the fluctuation analysis unit is preset with a voltage fluctuation standard and a frequency fluctuation standard, and compares the identified amplitude change value with the corresponding voltage fluctuation standard and frequency fluctuation standard, and generates a fluctuation analysis result according to the comparison result;

[0027] a deviation analysis unit connected to the data search unit; the deviation analysis unit sequentially obtains the voltage fluctuation curve and the frequency fluctuation curve, and identifies the maximum voltage value, the minimum voltage value, the maximum frequency value and the minimum frequency value in each curve; the deviation analysis unit is preset with a voltage standard value and a frequency standard value, and compares and calculates the identified maximum voltage value, minimum voltage value, maximum frequency value and minimum frequency value with the corresponding voltage standard value and frequency standard value, respectively, obtains the maximum voltage deviation, the minimum voltage deviation, the maximum frequency deviation and the minimum frequency deviation, and generates a deviation analysis result;

[0028] A harmonic analysis unit connected to the data search unit; the harmonic analysis unit obtains the frequency fluctuation curve, performs Fourier series decomposition on the periodic alternating current carried by the frequency fluctuation curve, determines whether harmonics are generated and the number of harmonics, and generates harmonic analysis results;

[0029] A balance analysis unit connected to the data search unit; the balance analysis unit obtains three-phase current values ​​and three-phase current average values, sequentially substitutes them into a preset balance calculation model, and obtains the three-phase current unbalance degree of each node through calculation; the balance analysis unit is preset with a balance standard, and compares the three-phase current unbalance degree with the preset balance standard, and generates a balance analysis result according to the comparison result;

[0030] A summary generation unit is connected to the fluctuation analysis unit, the deviation analysis unit, the harmonic analysis unit and the balance analysis unit, and is used to obtain the analysis results of each analysis unit, summarize and organize them, and generate corresponding alarm instructions according to abnormal analysis results.

[0031] As a preferred solution of a distributed power quality monitoring system described in the present invention, the balance calculation model includes:

[0032]

[0033] Among them, H is the three-phase current unbalance, is the average value of the three-phase current, I A is the average value of the three-phase current The current value of the phase with the largest difference.

[0034] As a preferred solution of a distributed power quality monitoring system described in the present invention, the processing and analysis module further includes:

[0035] a central node determination unit connected to the data search unit and the path-node-parameter model; the node prediction unit obtains the node position information of the central node of each path in the path-node-parameter model, and sends it to the data search unit, so that it searches for a data set matching the node position information as a first analysis data set, so that the fluctuation analysis unit, the deviation analysis unit, the harmonic analysis unit and the balance analysis unit give priority to analyzing various parameters of the node, and generate a central node analysis result after being summarized by the summary generation unit;

[0036] A prediction unit is connected to the summary generation unit and is used to receive the analysis result of the central node; the prediction unit establishes a prediction model and trains the model based on the historical data in the database; substitutes various parameters in the analysis result of the central node into the prediction model, predicts the analysis results of several nodes before and after it, and sends the prediction result to the summary generation unit to generate a prediction alarm instruction.

[0037] As a preferred solution of a distributed power quality monitoring system described in the present invention, the alarm feedback module includes:

[0038] An instruction receiving unit, connected to the summary generating unit, for receiving an alarm instruction and a prediction alarm instruction;

[0039] An alarm unit, connected to the instruction receiving unit, for performing an alarm action according to the alarm instruction and the predicted alarm instruction;

[0040] The feedback unit is connected to the alarm unit and is used to monitor personnel's confirmation after the alarm unit generates an alarm action, and delete the alarm instruction and the predicted alarm instruction after the personnel confirms.

[0041] As a preferred solution of a distributed power quality monitoring system described in the present invention, the feedback unit further includes:

[0042] After deleting the current alarm instruction and the predicted alarm instruction, the feedback unit sends the analysis result of the current alarm and the predicted analysis result in the summary generation unit to the database as historical data storage.

[0043] Beneficial effects of the present invention: a quality monitoring module, which is arranged at each node in the power grid and is used to collect power quality parameters of each node in the power grid; a communication network module, which is connected to the quality monitoring module and is used to transmit the collected power quality parameters; a central monitoring module, which is connected to the communication network module and is used to receive, process and store data transmitted by the monitoring equipment; a processing and analysis module, which is connected to the central monitoring module and is used to perform power quality analysis on the processed data; an alarm feedback module, which is connected to the processing and analysis module and is used to issue an alarm signal in time according to the analysis results and provide problem descriptions and suggestions; the present invention adopts a distributed remote monitoring method of automatic detection and analysis, without the need for on-site detection by personnel; at the same time, each node is predicted by obtaining a central node, thereby reducing the amount of data transmission per unit time and avoiding data transmission congestion. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. Among them:

[0045] Figure 1 A flow chart of a distributed power quality monitoring system provided by one embodiment of the present invention. DETAILED DESCRIPTION

[0046] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the drawings of the specification. Obviously, the described embodiments are part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary persons in the art without creative work should fall within the scope of protection of the present invention.

[0047] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0048] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor is it a separate or selective embodiment that is mutually exclusive with other embodiments.

[0049] The present invention is described in detail with reference to schematic diagrams. When describing the embodiments of the present invention, for the sake of convenience, the cross-sectional diagrams showing the device structure will not be partially enlarged according to the general scale, and the schematic diagrams are only examples, which should not limit the scope of protection of the present invention. In addition, in actual production, the three-dimensional dimensions of length, width and depth should be included.

[0050] At the same time, in the description of the present invention, it should be noted that the directions or positional relationships indicated by the terms "upper, lower, inner and outer" are based on the directions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first, second or third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0051] In the present invention, unless otherwise clearly specified and limited, the terms "install, connect, connect" should be understood in a broad sense, for example: it can be a fixed connection, a detachable connection or an integral connection; it can also be a mechanical connection, an electrical connection or a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0052] Example 1

[0053] Reference Figure 1, which is the first embodiment of the present invention, provides a distributed power quality monitoring system, including: a quality monitoring module, which is arranged at each node in the power grid and is used to collect power quality parameters of each node in the power grid;

[0054] A communication network module, which is connected to the quality monitoring module and is used to transmit the collected power quality parameters;

[0055] A central monitoring module, which is connected to the communication network module and is used to receive, process and store data transmitted by the monitoring equipment;

[0056] A processing and analysis module, which is connected to the central monitoring module and is used to perform power quality analysis on the processed data;

[0057] The alarm feedback module is connected to the processing and analysis module and is used to issue an alarm signal in a timely manner and provide problem descriptions and suggestions based on the analysis results.

[0058] The principle of the above embodiment is: multiple detection nodes are set in the power grid, and the detection unit is set at each node to realize distributed monitoring; the data is transmitted to the central monitoring model by using the communication network, and the central monitoring module is remotely set to realize remote monitoring; the data is stored as the prediction training data of the processing and analysis module; the processing and analysis module analyzes and predicts the data, and alarms and displays through the alarm feedback module.

[0059] The beneficial effects of the above-mentioned embodiment are: distributed monitoring and remote monitoring are realized, and at the same time, the prediction process is trained by using historical data to realize the prediction of power quality parameters and avoid data congestion.

[0060] To further optimize the above solution, please refer to Figure 1 , a distributed power quality monitoring system, the quality monitoring module includes:

[0061] A voltage detection unit is provided at each node in the power grid and is used to detect the voltage data of each node in real time;

[0062] A current detection unit is provided at each node in the power grid and is used to detect the three-phase current data of each node in real time;

[0063] The frequency detection unit is arranged at each node in the power grid and is used to detect the frequency data of each node in real time.

[0064] It should be noted that the detection principles of the voltage detection unit, the current detection unit and the frequency detection unit are existing technical means; this embodiment realizes distributed detection of the voltage, current and frequency of each node.

[0065] To further optimize the above solution, please refer to Figure 1 , a distributed power quality monitoring system, the quality monitoring module also includes:

[0066] The positioning unit is connected with the voltage detection unit, the current detection unit and the frequency detection unit; the positioning unit obtains the node position information of each detection unit, and connects the node position information in series according to the paths of each circuit in the power grid to generate a path-node model.

[0067] It should be noted that the positioning unit needs to know in advance the various paths in the power grid and the positions of each node in the paths. The establishment of the path-node model can be implemented using existing modeling software; this embodiment adds node location information, which can provide standards when adding nodes later.

[0068] To further optimize the above solution, please refer to Figure 1 , a distributed power quality monitoring system, the communication network module includes:

[0069] A collating unit, which is connected to the voltage detection unit, the current detection unit, the frequency detection unit and the positioning unit, and is used to insert the voltage data, the three-phase current data and the frequency data of the same node into the corresponding position in the path-node model to generate a path-node-parameter model carrying power quality parameters;

[0070] The wireless communication unit is connected to the sorting unit and is used for the wireless transmission path-node-parameter model.

[0071] It should be noted that the data insertion process of the sorting unit is a prior art method; the wireless communication unit can also be changed to a wired communication unit; this embodiment realizes the combination of model and data, and expresses the power quality parameters more intuitively.

[0072] To further optimize the above solution, please refer to Figure 1 , a distributed power quality monitoring system, the central monitoring module includes:

[0073] A data receiving unit, connected to the wireless communication unit, and configured to periodically receive a path-node-parameter model;

[0074] A preprocessing unit, which is connected to the data receiving unit, is used to preprocess the power quality parameters carried by each node in the path-node-parameter model; the preprocessing process includes drawing a voltage fluctuation curve, a frequency fluctuation curve, summarizing three-phase current values ​​and calculating the average value of the three-phase current;

[0075] A storage unit connected to the preprocessing unit and used to store the voltage fluctuation curve, the frequency fluctuation curve, the three-phase current values ​​and the three-phase current average values ​​in a database;

[0076] The classification unit is connected to the storage unit and is used to organize the voltage fluctuation curve, frequency fluctuation curve, three-phase current value and three-phase current average value of the same node in the database into the same data set, and set the data set name to the node location information and the time information of obtaining the data.

[0077] It should be noted that the data receiving unit periodically receives the path-node-parameter model, which period is a preset receiving period and monitoring period. The data receiving unit obtains a path-node-parameter model containing all data in a monitoring period from the wireless communication unit after each receiving period. This embodiment realizes the storage and classification of data, increases the traceability of data, and provides training samples for the prediction process.

[0078] To further optimize the above solution, please refer to Figure 1 , a distributed power quality monitoring system, the processing and analysis module includes:

[0079] A data search unit connected to the storage unit; the data search unit searches the database for a data set of each node closest to the current time value according to the current time value, and obtains the voltage fluctuation curve, frequency fluctuation curve, three-phase current value and three-phase current average value in the set;

[0080] A fluctuation analysis unit is connected to the data search unit; the fluctuation analysis unit sequentially obtains the voltage fluctuation curve and the frequency fluctuation curve, and identifies the amplitude change value at each time in each curve; the fluctuation analysis unit is preset with a voltage fluctuation standard and a frequency fluctuation standard, and compares the identified amplitude change value with the corresponding voltage fluctuation standard and frequency fluctuation standard, and generates a fluctuation analysis result according to the comparison result;

[0081] A deviation analysis unit is connected to the data search unit; the deviation analysis unit sequentially obtains the voltage fluctuation curve and the frequency fluctuation curve, and identifies the maximum voltage value, the minimum voltage value, the maximum frequency value and the minimum frequency value in each curve; the deviation analysis unit is preset with a voltage standard value and a frequency standard value, and compares and calculates the identified maximum voltage value, minimum voltage value, maximum frequency value and minimum frequency value with the corresponding voltage standard value and frequency standard value, respectively, obtains the maximum voltage deviation, the minimum voltage deviation, the maximum frequency deviation and the minimum frequency deviation, and generates a deviation analysis result;

[0082] A harmonic analysis unit connected to the data search unit; the harmonic analysis unit obtains the frequency fluctuation curve, performs Fourier series decomposition on the periodic alternating current carried by the frequency fluctuation curve, determines whether harmonics are generated and the number of harmonics, and generates harmonic analysis results;

[0083] A balance analysis unit is connected to the data search unit; the balance analysis unit obtains the three-phase current value and the three-phase current average value, and sequentially substitutes them into a preset balance calculation model to obtain the three-phase current imbalance of each node through calculation; the balance analysis unit is preset with a balance standard, and compares the three-phase current imbalance with the preset balance standard, and generates a balance analysis result according to the comparison result;

[0084] The summary generation unit is connected to the fluctuation analysis unit, the deviation analysis unit, the harmonic analysis unit and the balance analysis unit, and is used to obtain the analysis results of each analysis unit, summarize and organize them, and generate corresponding alarm instructions according to abnormal analysis results.

[0085] It should be noted that the equilibrium calculation model includes:

[0086] Among them, H is the three-phase current unbalance, is the average value of the three-phase current, I A is the average value of the three-phase current The current value of the phase with the largest difference; the analysis process of the harmonic analysis unit adopts the method of Fourier series decomposition for analysis, and its process is a prior art means; this embodiment realizes the analysis of instantaneous voltage fluctuations, instantaneous frequency fluctuations, voltage deviations, frequency deviations, harmonics and three-phase current imbalance, and the analysis results cover a comprehensive range, avoiding the problem that a single monitoring means in the prior art cannot truly reflect the power quality.

[0087] To further optimize the above solution, please refer to Figure 1 , a distributed power quality monitoring system, the processing and analysis module also includes:

[0088] A central node determination unit is connected to the data search unit and the path-node-parameter model; the node prediction unit obtains the node position information of the central node of each path in the path-node-parameter model, and sends it to the data search unit, so that it searches for a data set matching the node position information as the first analysis data set, so that the fluctuation analysis unit, the deviation analysis unit, the harmonic analysis unit and the balance analysis unit give priority to analyzing various parameters of the node, and the central node analysis result is generated after being summarized by the summary generation unit;

[0089] The prediction unit is connected to the summary generation unit and is used to receive the analysis results of the central node; the prediction unit establishes a prediction model and trains the model based on the historical data in the database; the various parameters in the analysis results of the central node are substituted into the prediction model, the analysis results of several nodes before and after it are predicted, and the prediction results are sent to the summary generation unit to generate a prediction alarm instruction.

[0090] It should be noted that since the current flows in each node on the same path, there are certain rules in the power quality parameters of each node; the prediction model is trained using historical data so that the predicted data best conforms to the actual situation of the power quality in each path; the power quality analysis results of the central node are preferably used for prediction, which can increase the accuracy of the prediction; this embodiment can reduce the rate of receiving data through prediction, reduce the amount of data transmission per unit time, avoid data congestion, and increase monitoring efficiency.

[0091] To further optimize the above solution, please refer to Figure 1 , a distributed power quality monitoring system, the alarm feedback module includes:

[0092] An instruction receiving unit, connected to the summary generating unit, for receiving an alarm instruction and a prediction alarm instruction;

[0093] An alarm unit, connected to the instruction receiving unit, for performing an alarm action according to the alarm instruction and the predicted alarm instruction;

[0094] The feedback unit is connected to the alarm unit and is used to monitor the personnel's confirmation after the alarm unit generates an alarm action, and delete the alarm instruction and the predicted alarm instruction after the personnel confirms.

[0095] It should be noted that after the feedback unit deletes the alarm instruction and the predicted alarm instruction, it will send the analysis results of the alarm and the predicted analysis results in the summary generation unit to the database as historical data storage; this embodiment realizes timely alarm for monitoring and prediction, and provides feedback based on the confirmed situation, thereby increasing the safety and intelligence of the monitoring system.

[0096] It should be noted that the system provided in the above embodiment is only illustrated by the division of the above functional modules. In practical applications, the above functions can be assigned to different functional modules as needed, that is, the modules or steps in the embodiments of the present invention can be decomposed or combined. For example, the modules in the above embodiments can be combined into one module, or further divided into multiple sub-modules to complete all or part of the functions described above. The names of the modules and steps involved in the embodiments of the present invention are only for distinguishing the modules or steps, and are not regarded as improper limitations of the present invention.

[0097] The term "comprise" or any other similar term is intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus / device that includes a list of elements includes not only those elements but also other elements not expressly listed, or also includes elements inherent to such process, method, article, or apparatus / device.

[0098] So far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present invention.

[0099] Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations in the above description of the disclosed embodiments, so that professionals and technicians in the field can implement or use the present invention. Various modifications to these embodiments will be obvious to professionals and technicians in the field, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but will conform to the widest range consistent with the principles and novel features disclosed herein.

Claims

1. A distributed power quality monitoring system, characterized in that: include, The quality monitoring module is arranged at each node in the power grid and is used to collect the power quality parameters of each node in the power grid; A communication network module, connected to the quality monitoring module, for transmitting the collected power quality parameters; A central monitoring module, connected to the communication network module, for receiving, processing and storing data transmitted by the monitoring equipment; A processing and analysis module, connected to the central monitoring module, for performing power quality analysis and power quality prediction on the processed data; The alarm feedback module is connected to the processing and analysis module and is used to issue an alarm signal in a timely manner and provide problem descriptions and suggestions based on the analysis results and prediction results.

2. A distributed power quality monitoring system as claimed in claim 1, characterized in that: The quality monitoring module includes: A voltage detection unit is provided at each node in the power grid and is used to detect the voltage data of each node in real time; A current detection unit is provided at each node in the power grid and is used to detect the three-phase current data of each node in real time; The frequency detection unit is arranged at each node in the power grid and is used to detect the frequency data of each node in real time.

3. A distributed power quality monitoring system as claimed in claim 2, characterized in that: The quality monitoring module also includes: A positioning unit is connected to the voltage detection unit, the current detection unit and the frequency detection unit; the positioning unit obtains the node position information of each detection unit, and generates a path-node model according to the path series node position information of each circuit in the power grid.

4. A distributed power quality monitoring system as claimed in claim 3, characterized in that: The communication network module comprises: a collating unit, connected to the voltage detection unit, the current detection unit, the frequency detection unit and the positioning unit, and configured to insert the voltage data, the three-phase current data and the frequency data of the same node into corresponding positions in the path-node model to generate a path-node-parameter model carrying power quality parameters; A wireless communication unit is connected to the collating unit and is used for wirelessly transmitting the path-node-parameter model.

5. A distributed power quality monitoring system as claimed in claim 4, characterized in that: The central monitoring module includes: a data receiving unit, connected to the wireless communication unit, and configured to periodically receive the path-node-parameter model; A preprocessing unit connected to the data receiving unit, for preprocessing the power quality parameters carried by each node in the path-node-parameter model; the preprocessing process includes drawing a voltage fluctuation curve, a frequency fluctuation curve, summarizing three-phase current values ​​and calculating the average value of the three-phase current; A storage unit connected to the preprocessing unit and used to store the voltage fluctuation curve, the frequency fluctuation curve, the three-phase current values ​​and the three-phase current average values ​​in a database; A classification unit is connected to the storage unit and is used to organize the voltage fluctuation curve, frequency fluctuation curve, three-phase current value and three-phase current average value of the same node in the database into the same data set, and set the data set name to the node location information and the time information of obtaining the data.

6. A distributed power quality monitoring system as claimed in claim 5, characterized in that: The processing and analysis module comprises: A data search unit connected to the storage unit; the data search unit searches the database for a data set of each node closest to the current time value according to the current time value, and obtains the voltage fluctuation curve, frequency fluctuation curve, three-phase current value and three-phase current average value in the set; A fluctuation analysis unit connected to the data search unit; the fluctuation analysis unit sequentially obtains the voltage fluctuation curve and the frequency fluctuation curve, and identifies the amplitude change value at each time in each curve; the fluctuation analysis unit is preset with a voltage fluctuation standard and a frequency fluctuation standard, and compares the identified amplitude change value with the corresponding voltage fluctuation standard and frequency fluctuation standard, and generates a fluctuation analysis result according to the comparison result; a deviation analysis unit connected to the data search unit; the deviation analysis unit sequentially obtains the voltage fluctuation curve and the frequency fluctuation curve, and identifies the maximum voltage value, the minimum voltage value, the maximum frequency value and the minimum frequency value in each curve; the deviation analysis unit is preset with a voltage standard value and a frequency standard value, and compares and calculates the identified maximum voltage value, minimum voltage value, maximum frequency value and minimum frequency value with the corresponding voltage standard value and frequency standard value, respectively, obtains the maximum voltage deviation, the minimum voltage deviation, the maximum frequency deviation and the minimum frequency deviation, and generates a deviation analysis result; A harmonic analysis unit connected to the data search unit; the harmonic analysis unit obtains the frequency fluctuation curve, performs Fourier series decomposition on the periodic alternating current carried by the frequency fluctuation curve, determines whether harmonics are generated and the number of harmonics, and generates harmonic analysis results; A balance analysis unit connected to the data search unit; the balance analysis unit obtains three-phase current values ​​and three-phase current average values, sequentially substitutes them into a preset balance calculation model, and obtains the three-phase current unbalance degree of each node through calculation; the balance analysis unit is preset with a balance standard, and compares the three-phase current unbalance degree with the preset balance standard, and generates a balance analysis result according to the comparison result; A summary generation unit is connected to the fluctuation analysis unit, the deviation analysis unit, the harmonic analysis unit and the balance analysis unit, and is used to obtain the analysis results of each analysis unit, summarize and organize them, and generate corresponding alarm instructions according to abnormal analysis results.

7. A distributed power quality monitoring system as claimed in claim 6, characterized in that: The equilibrium calculation model includes: Among them, H is the three-phase current unbalance, is the average value of the three-phase current, I A is the average value of the three-phase current The current value of the phase with the largest difference.

8. A distributed power quality monitoring system as claimed in claim 7, characterized in that: The processing and analysis module also includes: a central node determination unit connected to the data search unit and the path-node-parameter model; the node prediction unit obtains the node position information of the central node of each path in the path-node-parameter model, and sends it to the data search unit, so that it searches for a data set matching the node position information as a first analysis data set, so that the fluctuation analysis unit, the deviation analysis unit, the harmonic analysis unit and the balance analysis unit give priority to analyzing various parameters of the node, and generate a central node analysis result after being summarized by the summary generation unit; A prediction unit is connected to the summary generation unit and is used to receive the analysis result of the central node; the prediction unit establishes a prediction model and trains the model based on the historical data in the database; substitutes various parameters in the analysis result of the central node into the prediction model, predicts the analysis results of several nodes before and after it, and sends the prediction result to the summary generation unit to generate a prediction alarm instruction.

9. A distributed power quality monitoring system as claimed in claim 5, characterized in that: The alarm feedback module comprises: An instruction receiving unit, connected to the summary generating unit, for receiving an alarm instruction and a prediction alarm instruction; An alarm unit, connected to the instruction receiving unit, for performing an alarm action according to the alarm instruction and the predicted alarm instruction; The feedback unit is connected to the alarm unit and is used to monitor personnel's confirmation after the alarm unit generates an alarm action, and delete the alarm instruction and the predicted alarm instruction after the personnel confirms.

10. A distributed power quality monitoring system as claimed in claim 5, characterized in that: The feedback unit also includes: After deleting the current alarm instruction and the predicted alarm instruction, the feedback unit sends the analysis result of the current alarm and the predicted analysis result in the summary generation unit to the database as historical data storage.

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