Distribution network relay protection equipment monitoring method and system based on intelligent simulation

Abstract

The invention relates to the technical field of new power systems, and discloses a distribution network relay protection equipment monitoring method and system based on intelligent simulation, and the method comprises the steps: building a simulation model of relay protection equipment, and analyzing the operation state of the relay protection equipment according to the simulation model. And based on the three-dimensional parallel scatter diagram, in combination with human-computer interaction, visualizing an analysis result. And controlling the relay protection device to execute a protection action according to an analysis result. The operation and maintenance efficiency is greatly improved, manual intervention is reduced, and the safety and stability of a power system are improved. And the platform monitors and identifies abnormal data in real time and gives an alarm in time, so that the fault response time is greatly shortened. The reliability and the safety of a power system are remarkably improved, and power failure and loss caused by faults are reduced.

Description

Technical Field

[0002] The present invention relates to the technical field of new power systems, and particularly to a monitoring method and system for distribution network relay protection equipment based on intelligent simulation. Background Art

[0004] With the influx of new energy, the power system is undergoing a major transformation. The operation monitoring platform for relay protection equipment on the distribution network side is crucial for the development of the new power system, ensuring the stable and reliable operation of the power system. The stable operation of the power system is of great significance to social production and people's lives. With the influx of new energy, the traditional operation monitoring mode of relay protection equipment on the distribution network side has become outdated.

[0005] In the context of a large number of new energy sources in the power system, the operation monitoring of relay protection equipment on the distribution network side faces new challenges. On the one hand, the entry of new energy makes the operation environment of the power system more complex, which puts higher requirements on the stability and reliability of relay protection equipment on the distribution network side. On the other hand, traditional operation monitoring methods for relay protection equipment on the distribution network side have problems such as low informatization level and low intelligence, making it difficult to achieve real-time and accurate monitoring and early warning, and unable to meet the requirements of the stability and reliability of modern power systems.

[0006] A platform for monitoring the operation of relay protection equipment on the distribution network side suitable for the new power system has been proposed. The innovative features of this platform are as follows: (1) By establishing simulation models of different types of relay protection equipment on the distribution network side, the operation status of relay protection equipment can be obtained in real time. (2) Fault phase selection and action evaluation methods are adopted to obtain the fault time, fault type, and current action of relay protection equipment on the distribution network side, realizing the monitoring of the operation status of relay protection equipment on the distribution network side. (3) The human-computer interaction adopts a visualization representation method based on a three-dimensional parallel scatter plot and monitoring data of human-computer interaction. (4) The electromechanical protection device is controlled by the relay protection setting method to achieve instantaneous overcurrent protection and overcurrent protection. Summary of the Invention

[0008] In view of the above existing problems, the present invention is proposed.

[0009] Therefore, the technical problems solved by the present invention are: the entry of new energy makes the operation environment of the power system more complex, which puts higher requirements on the stability and reliability of relay protection equipment on the distribution network side. On the other hand, traditional operation monitoring methods for relay protection equipment on the distribution network side have problems such as low informatization level and low intelligence, making it difficult to achieve real-time and accurate monitoring and early warning, and unable to meet the requirements of the stability and reliability of modern power systems.

[0010] To solve the above technical problems, the present invention provides the following technical solution: A method for monitoring relay protection equipment of a distribution network based on intelligent simulation, comprising: establishing a simulation model of the relay protection equipment, and analyzing the operating state of the relay protection equipment according to the simulation model.

[0011] Based on a three-dimensional parallel scatter plot, combined with human-computer interaction, visualize the analysis results.

[0012] According to the analysis results, control the relay protection device to perform protection actions.

[0013] As a preferred solution of the method for monitoring relay protection equipment of a distribution network based on intelligent simulation according to the present invention, wherein: the establishment of the simulation model of the relay protection equipment includes, respectively, according to the states of the overcurrent relay and the impedance protection relay, establishing a state block diagram, using an arrowed connection line to represent the fault situation of the relay, and the direction of the arrow representing the relay state conversion caused by the fault situation, thereby establishing a simulation model of overcurrent protection and a simulation model of impedance protection equipment.

[0014] As a preferred solution of the method for monitoring relay protection equipment of a distribution network based on intelligent simulation according to the present invention, wherein: the analysis of the operating state of the relay protection equipment according to the simulation model includes, during the simulation process of the relay protection equipment on the distribution network side, completing the state conversion of the simulation model through the monitoring of faults;

[0015] The monitoring of the faults includes collecting the real-time operating state information of the equipment, and using a support vector machine to diagnose the operating faults of the relay protection equipment on the distribution network side to achieve fault monitoring.

[0016] The real-time operating state information includes calculating the three-phase current on the high-voltage side according to the currents in different directions of the diagnostic transformer on the high-voltage side; setting the resistances of the three-phase windings A, B, C and the neutral point as resistance one, resistance two, resistance three, and resistance four respectively, and dividing the weighted sum of the current measurement values of each resistance within a unit time by 4 to obtain the measurement values of the phase currents;

[0017]

[0018] wherein, represents the measurement value of phase current a, represents the measurement value of phase current b, represents the measurement value of phase current c; represents the current measurement value of resistance one within the unit time represents the current measurement value of resistance two within the unit time represents the current measurement value of resistance three within the unit time represents the current measurement value of resistance four within the unit time represents the current measurement value of resistance three within the unit time represents the current measurement value of resistance four within the unit time Indicates within a unit time The measured value of the current of resistor four;

[0019] Balance coefficient Is expressed as:

[0020]

[0021] Wherein, Represents the average value of the three-phase current.

[0022] As a preferred scheme of the monitoring method for distribution network relay protection equipment based on intelligent simulation according to the present invention, wherein: the analyzing the operating state of the relay protection equipment according to the simulation model further includes, in the relay protection simulation model, determining whether there is a fault in the system by analyzing the signal action state. When no fault occurs, the fault of the system is determined as protection misoperation. When a fault occurs, the action of the system is determined as protection refusal.

[0023] Operate and misoperate the circuit breaker, judge whether the circuit trips, and obtain the misoperation state set of the circuit breaker .

[0024] After obtaining the suspicious equipment in the actual fault, obtain the analytical solution of the model, and introduce the equivalent equation into the replacement model.

[0025] Based on the support vector machine method, classify the obtained fault samples of the relay protection device. In the training sample set, judge whether the samples are linearly separable, and the classification decision function of the optimal hyperplane is expressed as:

[0026]

[0027] Wherein, Represents the value of the classification decision function of the optimal hyperplane. Represents the sign function. Represents the training weight of the vector machine. Represents the training classification constant value. Represents the inner product of the weights.

[0028] Classify according to the fault samples, separate all samples, and reduce misclassification.

[0029] Under the constraint of the inequality, each sample determines the reflection value according to the actual relaxation factor, and the discriminant function of the generalized optimal classification surface is expressed as:

[0030]

[0031] Wherein, Represents the value of the discriminant function. n represents the number of samples. Represents the transformation parameter of the feature. When indicates that the discrimination result of the sample under the algorithm is 1, indicating that there is a fault in the classification plane. When indicates that the discrimination result of the sample under the algorithm is 0, indicating that there is no fault in the classification plane.

[0032] As a preferred solution of the monitoring method for distribution network relay protection equipment based on intelligent simulation according to the present invention, wherein: the visualization of the analysis result by combining the three-dimensional parallel scatter plot with human-computer interaction includes using the RDD class acquisition method to obtain real-time data from the power equipment online monitoring system, extracting equipment status information, forming an elastic distribution data set RDDs, and constructing a data structure of a specified type.

[0033] Parse the data set according to the data type, split it into a cluster number list and a data point set list. After the data classification is completed, assign a color to each cluster number to construct a coloring list.

[0034] Use the three-dimensional scatter method to combine the data point set with the coloring list to generate a three-dimensional parallel scatter plot, presenting the distribution characteristics of the power equipment status.

[0035] Adopt the instruction method of the chart class, add human-computer interaction operations, and support the decomposition display of the relationship between each attribute and time. Display the visualization result through the openChart method.

[0036] As a preferred solution of the monitoring method for distribution network relay protection equipment based on intelligent simulation according to the present invention, wherein: the control of the relay protection device to perform protection actions according to the analysis result includes performing current quick-break protection and overcurrent protection.

[0037] The current quick-break protection includes dividing the product of the reliability coefficient and the maximum three-phase short-circuit current on the low-voltage side of the transformer by the sum of the positive-sequence short-circuit impedance value under the maximum operating mode of the system and the positive-sequence impedance from this line to the next switch outlet position to obtain the primary value of the current quick-break.

[0038] When there is only one transformer at the end of the line, the differential protection is the active protection method. The overall whole line is realized according to the fixed value of the differential protection. If the current reaches the fixed value of the differential protection, the quick-break protection is started; the fixed value of the differential protection is expressed as:

[0039]

[0040] Among them, The value range is 1.3~1.4; represents the maximum current limit of the relay.

[0041] As a preferred solution of the monitoring method for distribution network relay protection equipment based on intelligent simulation according to the present invention, wherein: the overcurrent protection includes setting the overcurrent protection principle to avoid the maximum load current of the switch during normal operation and ensuring the sensitivity of the switch line during normal operation. When the current reaches the fixed value of the overcurrent protection, the overcurrent protection is activated; during normal operation, the fixed value of the overcurrent protection is expressed as:

[0042]

[0043] wherein, the value range is 1.15 - 1.25, represents the return coefficient, with a value of 0.85, represents the self - starting coefficient of the motor, with a value range of 1.5 - 2.5, represents the maximum load current at this stage.

[0044] The sensitivity verification of the switch line includes that the sensitivity coefficient of the line below 20 km is not less than 1.5. The sensitivity coefficient of the line between 20 - 50 km is not less than 1.4. The sensitivity coefficient of the line above 50 km is not less than 1.3. When a fault occurs in the adjacent line, the maximum sensitivity is not less than 1.2.

[0045] A monitoring system for distribution network relay protection equipment based on intelligent simulation, wherein: it includes,

[0046] A simulation model establishment module, which establishes a simulation model of the relay protection equipment and analyzes the operating state of the relay protection equipment according to the simulation model.

[0047] A visualization module, which visualizes the analysis results based on a three - dimensional parallel scatter plot and combines human - machine interaction.

[0048] An execution of protection action module, which controls the relay protection device to execute protection actions according to the analysis results.

[0049] A computer device includes a memory and a processor. The memory stores a computer program, and when the processor executes the computer program, it implements the steps of the method described above.

[0050] A computer - readable storage medium stores a computer program, and when the computer program is executed by a processor, it implements the steps of the method described above.

[0051] The beneficial effects of the present invention: In response to the development trend of the new power system, especially its requirements for digitization, intelligence, and adaptability. This reflects the innovation of the traditional power system management and operation and maintenance mode to adapt to the increasing complexity and intelligent needs of the modern power system.

[0052] A comprehensive monitoring platform for the operation of relay protection equipment at the distribution network end is proposed. This platform not only has real-time monitoring functions but also can achieve intelligent management. This comprehensive management method greatly improves the operation and maintenance efficiency, reduces manual intervention, and enhances the security and stability of the power system.

[0053] The platform adopts three core modules: data acquisition, data processing, and data display. This modular design makes the system more flexible, easier to expand and maintain. At the same time, each module can be independently optimized and upgraded to adapt to changing requirements and technological progress.

[0054] Through the intelligent alarm system, the platform can monitor and identify abnormal data in real time and send out alarms in a timely manner, thus greatly shortening the fault response time. This intelligent early warning mechanism can significantly improve the reliability and security of the power system and reduce power outages and losses caused by faults. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings. Among them:

[0057] Figure 1 It is the overall flowchart of a method and system for monitoring distribution network relay protection equipment based on intelligent simulation provided by the first embodiment of the present invention.

[0058] Figure 2 It is the hybrid automaton model diagram of the overcurrent relay for a method and system for monitoring distribution network relay protection equipment based on intelligent simulation provided by the first embodiment of the present invention.

[0059] Figure 3 It is the action circle diagram of the directional impedance relay for a method and system for monitoring distribution network relay protection equipment based on intelligent simulation provided by the first embodiment of the present invention.

[0060] Figure 4 It is the simulation model diagram of the impedance protection relay equipment for a method and system for monitoring distribution network relay protection equipment based on intelligent simulation provided by the first embodiment of the present invention.

[0061] Figure 5 It is the schematic diagram of the single-ended double-loop system of the experimental object for a method and system for monitoring distribution network relay protection equipment based on intelligent simulation provided by the second embodiment of the present invention.

[0062] Figure 6The current and voltage monitoring result diagram of the relay protection device for a power distribution network relay protection device monitoring method and system based on intelligent simulation provided by the second embodiment of the present invention.

[0063] Figure 7 The platform vision display ability test diagram for a power distribution network relay protection device monitoring method and system based on intelligent simulation provided by the second embodiment of the present invention.

[0064] Figure 8 The visualization diagram of the current of the relay protection device under different lines for a power distribution network relay protection device monitoring method and system based on intelligent simulation provided by the second embodiment of the present invention. Detailed implementation manners

[0066] To make the above objects, features, and advantages of the present invention more obvious and understandable, the following will describe the detailed implementation manners of the present invention in conjunction with the drawings of the specification. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of them. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0067] Example 1, referring to Figures 1 to 4 , which is an embodiment of the present invention, provides a power distribution network relay protection device monitoring method based on intelligent simulation, including:

[0068] S1: Establish a simulation model of the relay protection device and analyze the operating state of the relay protection device according to the simulation model.

[0069] According to the states of the overcurrent relay and the impedance protection relay respectively, establish state block diagrams, and use arrow-connected lines to represent the fault conditions of the relays. The direction of the arrow indicates the relay state conversion caused by the fault conditions, thereby establishing the simulation models of the overcurrent protection and the impedance protection device.

[0070] It should be noted that the new power system is a clean, low-carbon, safe, controllable, flexible, efficient, intelligent, user-friendly, and open system, with new energy as the main power supplier. Its primary goal is to meet the power demand for economic and social development, and energy and power security remain its basic premise. The system is centered around a powerful smart grid and relies on the support of multi-energy complementarity. It includes related links such as power generation, grid operation, and power consumption. By adopting new technologies to optimize the existing power system, the dual goals of environmental protection and high reliability are achieved.

[0071] In the context of the new power system, the operation monitoring platform for relay protection equipment on the distribution network side integrates multiple key components that interact with each other to achieve real-time monitoring of the operation status of the power system, fault alarm, and protection control.

[0072] This platform consists of a human-machine interaction terminal, a firewall, a core switch, a network message recording and analysis device, a regional switch, a measurement device, and a shock suppression device. These components are connected through a complex network to form an effective monitoring and protection system. The firewall ensures data security, the core switch enables high-speed data forwarding, the network message recording and analysis device provides real-time data analysis, the regional switch realizes network segmentation management, the measurement device monitors the parameters of the power system, and the shock suppression device protects the system from shocks. Each component interacts with each other to jointly monitor the operation of the relay protection equipment on the distribution network side.

[0073] The technical specifications and performance indicators of this equipment are as follows: The selected equipment has high performance technical specifications and stable performance indicators. The firewall has strong security filtering capabilities, the core switch has the characteristics of high bandwidth and low latency, the network message recording and analysis device can analyze network data quickly and accurately, the regional switch has high reliability and flexibility, the measurement device has high precision and real-time performance, and the shock suppression device can respond quickly and suppress shocks. These devices comply with industry standards and specifications and are selected because they can meet the security, stability, and real-time requirements of the monitoring platform.

[0074] The challenges faced in integrating these components mainly include equipment compatibility, network topology design, and data security. To ensure equipment compatibility, we selected equipment that complies with industry standards and conducted strict tests. In network topology design, redundant design and segmented management methods were adopted to improve the reliability and stability of the network. In terms of data security, advanced firewalls and encryption technologies have been deployed to ensure the security of data transmission and storage. Through these measures, the challenges in the integration process have been successfully addressed.

[0075] Furthermore, overcurrent relays exist in the main equipment of the power system, such as transformers and motors, as well as in the circuits of power transmission and distribution lines. If these devices experience a certain degree of failure, the overcurrent relay will issue an action signal within a preset time range, enabling the circuit breaker to isolate the fault and thus ensuring the safety of other equipment and lines. Based on the working principle of the overcurrent relay and the principle of hybrid automata modeling, a hybrid automata model of the overcurrent relay was established, as Figure 2 shown.

[0076] The hybrid automaton model of the overcurrent relay includes the states of "idle", "wait", "ready", "trip" and "stuck", as well as five transition conditions of "fault detection", "fault elimination", "timeout", "trip_cb" and "stuck relay". In the initial idle state, once the current exceeds the preset threshold, the relay enters the fault detection state. When the fault is eliminated, it is the Fault_demoved state, and can enter the waiting state to confirm whether the fault is completely eliminated. If the waiting state is not eliminated during the waiting period and the time exceeds the preset threshold, it enters the Time_out state. The relay may fall into the stuck state due to mechanical or electrical faults. When the fault is completely eliminated and the Time_out is not triggered, the relay returns to the ready state and is ready to perform the protection function again. If a serious overcurrent fault is detected or the fault lasts for too long, the relay directly enters the trip state and triggers the trip operation. In addition, the "stuck-relay" and "Trip_cb" states in the model represent the specific situations of relay interference and execution of the trip operation mechanism, respectively. By analyzing the internal protection principle of the overcurrent relay and establishing the hybrid automaton model of the overcurrent relay, the action behavior of the overcurrent relay protection can be accurately simulated using simulation software.

[0077] Furthermore, impedance relays are a type of relay used in distance protection. Their object is the actual resistance of the line, so it is necessary to analyze the resistance of the line. The action characteristics of directional impedance relays on the resistance surface are the circular area through the origin, such as Figure 3 As shown. The action area of ​​the directional impedance relay is within this action circle, while the braking area of ​​the directional impedance relay is outside this action circle. When the forward direction fails, the resistance value obtained falls in the first quadrant of the coordinate diagram. As long as the coordinate value of the measured impedance falls within this circle, the protection starts. When the protection is reverse short-circuited, the obtained resistance value coordinate falls in the third quadrant of the coordinate diagram, and the coordinate value of the measured resistance value cannot fall within this circle. At this time, the relay refuses to act, so the device has a certain directional characteristic.

[0078] The action circle of the directional impedance relay is determined by determining its action impedance. and The phase difference between Different, at this time The action boundary value will also change accordingly. If the phase difference in some cases Angle with set value The time between is the same, then the action boundary value at this time is equal to the diameter of the action circle and reaches its maximum value. At this time, the line length that the directional impedance relay can protect reaches its maximum value, and its working sensitivity also reaches its maximum value. Therefore, this special impedance angle is generally called the maximum sensitivity angle, which is basically used is described. When the line fails, the impedance angle measured by the instrument is equal to the actual impedance angle of the line, that is . However, generally speaking, if it is desired that the relay operates with maximum sensitivity, the impedance angle should be selected and set . But when and are not equal, that is, the actual operating boundary value will be less than the set boundary value . At this time, the operating condition is not the so-called less than , precisely speaking, it is less than . Through phase comparison, when falls on the circumference of the operating circle, the phase difference between the impedance and is . Similar to the analysis of the principle of the full-impedance relay, the prerequisite for the normal operation of the directional impedance relay can also be determined .

[0079] Both of the two currents and are multiplied by to obtain two voltage comparison phases. These values include:

[0080]

[0081]

[0082] In the formula, represents the terminal voltage, represents the open-circuit voltage. And the equation for its function is:

[0083]

[0084] Similarly, represents the polarized voltage, represents the compensated voltage. The simulation model of the impedance protection relay device is as shown in Figure 4 .

[0085] By Figure 4It can be seen that the coordination performance of the impedance protection relay device simulation model is one of the important indicators for evaluating its operation effect in the simulated power system. For different types of impedance relays, a simulation model of the impedance protection relay device can be established. Each relay establishes a corresponding mathematical model according to its impedance characteristics, simulating impedance relays with different input signals and output contact types to meet the protection requirements of different power systems, having an adaptive ability to dynamically adjust the protection boundary according to the change of the transition resistance at the fault point to ensure the protection performance under different fault conditions. The hybrid automaton model of the impedance relay includes six states: "idle", "waiting 1", "waiting 2", "ready", "tripping", "stuck". It includes nine transition conditions: "Zone1_fault_detected", "Zone2_fault_detected", "Zone3_fault_detected", "Zone2_fault_removed", "Zone3_fault_removed", "Zone2_time_out", "Zone3_time_out", "trip_cb", "star_reeay". Using the hybrid automaton model for the impedance relay, the real-time action state of the impedance relay device can be obtained, and the error can be obtained from the real-time monitoring result.

[0086] The relay protection simulation environment based on the hybrid automaton usually includes the following key parts: (1) Hybrid automaton model construction: Based on the finite state set automaton model, by introducing two elements of "state" and "transition", the hybrid automaton model can reflect the actual role of relay protection in the power system. (2) Simulation software: A powerful power system simulation software is used for simulation. Through the simulation software, a digital simulation system can be established, and various operating states and faults of the power system can be simulated. (3) Data interface: In order to convert the simulation results into the signals required for testing the relay protection device, a data interface needs to be established to convert the simulation results into analog signals such as voltage and current. (4) Test equipment: It includes voltage and current amplifiers, digital output ports, etc., which are used to send analog signals to the relay protection device and the controller for testing. (5) Feedback mechanism: The response signals of the relay protection device and the controller under test are fed back to the computer in real time through the analog and status input ports to form an interaction, thus forming a complete real-time closed-loop test process.

[0087] The verification process is as follows:

[0088] Step 1: Benchmarks and standards: The verification process follows relevant standards in the international or domestic power industry, such as IEC60255, GB / T, to ensure the accuracy and reliability of the simulation results.

[0089] Step 2: Model Verification: By comparing the simulation results with the theoretical calculation results or actual test results, the accuracy and effectiveness of the hybrid automaton model are verified. This includes verifying whether the model can correctly reflect various fault types when the input state of the pressure plate and protection settings are given.

[0090] Step 3: Fault Reproduction and Verification: Use the actual fault voltage and current data used by the fault recorder to reproduce the fault process, and verify the working principle, action equation, action characteristics and setting values of the protection device. After verifying and solving the software problem, it can be proved that the problem lies in the hardware of the device, thus narrowing the scope of fault finding.

[0091] Step 4: Setting and Configuration Verification: Model and simulate the actual distribution line, analyze and verify the configuration and settings of its relay protection, and discover hidden faults in the configuration settings.

[0092] Power system simulation software such as Matlab is mainly used for modeling and simulation. At the same time, programming languages such as VC and VB are also needed to develop simulation and test function modules and design a graphical interface. The hardware includes voltage and current amplifiers, digital output ports, analog and status input ports, and data processing devices such as computers.

[0093] Compared with other simulation models, the relay protection simulation model based on hybrid automaton has the following advantages:

[0094] (1) High precision: By introducing "state" and "transition" elements, the hybrid automaton model can more accurately reflect the actual role of relay protection in the power system.

[0095] (2) Strong scalability: The model has good scalability. Only by giving its action criterion can the protection with new principles be easily added to the protection simulation unit.

[0096] (3) Real-time closed-loop test: By forming a complete real-time closed-loop test process, the dynamic performance of relay protection devices and controllers can be tested and verified in real time.

[0097] It should be noted that during the simulation process of relay protection equipment on the distribution network side, the state conversion of the simulation model is completed through the monitoring of faults; the monitoring of the faults includes collecting the real-time operation status information of the equipment. Using the support vector machine, a hidden fault judgment function of relay protection equipment on the distribution network side can be established. Through this function, the operation faults of relay protection equipment on the distribution network side can be diagnosed to achieve fault monitoring.

[0098] Let the resistances of the three-phase windings A, B, C and the neutral point be Resistance One, Resistance Two, Resistance Three, and Resistance Four respectively; due to the different distances of Phase A, Phase B, and Phase C, weighted values are applied to the measured current values of Resistance Two and Resistance Three; based on the currents in different directions of the high-voltage side diagnostic transformer, the three-phase currents on the high-voltage side are expressed as:

[0099]

[0100] Among them, represents the measured value of the phase current a, represents the measured value of the phase current b, represents the measured value of the phase current c. represents the measured current value of Resistance One within the unit time , represents the measured current value of Resistance Two within the unit time , represents the measured current value of Resistance Three within the unit time , represents the measured current value of Resistance Four within the unit time . represents the balance coefficient on the high-voltage side.

[0101] Balance coefficient The calculation is expressed as:

[0102]

[0103] Among them, represents the average value of the three-phase currents.

[0104] Combining the above model, the acquisition decision value of the measurement data of the relay protection device can be obtained. In the relay protection model, by analyzing the signal action state, it is determined whether there is a fault in the system. When no fault occurs, the fault of the system is called protection misoperation. When a fault occurs, the action of the system is called protection refusal. For the misoperation and malfunction of the circuit breaker, it is judged by whether they trip, so as to obtain the misoperation state set of the circuit breaker .

[0105] Thus, the suspicious equipment in the actual fault is obtained, the analytical solution of the model is obtained, and the above equivalent equation is introduced into the replacement model. Based on the support vector machine method, the fault samples of the relay protection device obtained by the above method are classified. In the given training sample set, it is judged whether the samples are linearly separable, and the classification decision function of the optimal hyperplane is obtained:

[0106]

[0107] Among them, Represents the value of the classification decision function of the optimal hyperplane. Represents the sign function. Represents the training weights of the vector machine. Represents the classification constant value obtained from training. Represents the inner product of the weights.

[0108] The data on the hyperplane can be classified according to the above samples, separating all samples and reducing misclassification. Under the constraints of the inequality, each sample needs to determine the reflection value according to the actual slack factor to obtain the discriminant function of the generalized optimal classification surface:

[0109]

[0110] Among them, Represents the value of the discriminant function. n represents the number of samples. Represents the transformation parameter of the feature. When , it means that the discriminant result of the sample under the algorithm is 1, indicating that there is a fault in the classification surface. When , it means that the discriminant result of the sample under the algorithm is 0, indicating that there is no fault in the classification surface.

[0111] S2: Based on the three-dimensional parallel scatter plot, combined with human-computer interaction, visualize the analysis results.

[0112] It should be noted that on the Spark big data computing platform, through the three-dimensional big data visualization library, the visualization display of power equipment status monitoring data is realized, and the implementation steps are as follows:

[0113] Step 1: Read the online monitoring data information of power equipment using the RDD class collection method, extract the elastic distribution dataset RDDs of equipment status information, and generate a List <vector>List of device status information elements of a type, where the vector structure is {number of clusters , time point , number of monitored } (where is the dimension of the monitored data set).

[0114] Step 2: Decompose each data element of each type in the list into the number of clusters and the data point set , and then construct the corresponding list of the number of clusters and the list of data point sets .

[0115] Step 3: Specify the corresponding color for each cluster number in the cluster number list to form the coloring list .

[0116] Step 4: Use the coloring list and the list of data point sets as input data to establish a three-dimensional parallel scatter plot using the three-dimensional scatter method.

[0117] Step 5: Add human-computer interaction operations using the instruction method of the chart class, such as z-axis translation, z-axis stretching, central rotation, decomposition and display of the relationship between each attribute and time, etc., to the established three-dimensional parallel scatter plot, and display the visualization result using the openChart method.

[0118] In the actual application scenario, users give positive feedback on the data visualization tool based on the three-dimensional parallel scatter plot and human-computer interaction. This visualization method can intuitively display the relationships and trends between multi-dimensional data, which helps to better understand and analyze the data. At the same time, the human-computer interaction function enables users to explore the data more flexibly, improving the efficiency and accuracy of data analysis.

[0119] The usability test results show that the visualization tool has good usability and usage efficiency. Users can quickly master its usage and effectively use it for data analysis. However, some users put forward some improvement suggestions, such as adding more interaction functions and optimizing the visualization effect. These suggestions will provide useful references for the subsequent improvement of the tool.

[0120] The challenges and solutions faced in developing the visualization tool are as follows:

[0121] (1) Data complexity:

[0122] Challenge: Multidimensional data is complex. How to effectively map it to a three-dimensional space to make it easy to understand and analyze is a challenge.

[0123] Solution: Dimensionality reduction techniques (such as principal component analysis, t-SNE, etc.) are used to reduce multidimensional data to a three-dimensional space while preserving the main features and development trends of the data. In addition, visual elements such as colors and sizes can be used to enhance the readability of the data.

[0124] (2) Visualization effect:

[0125] Challenge: How to select appropriate visualization parameters and effects to clearly display the relationships and trends between data is a difficult problem.

[0126] Solution: Select appropriate parameters and effects through comparative experiments and visual effect evaluation tools. At the same time, continuous adjustment and optimization can also be carried out according to user feedback and usability test results.

[0127] (3) Human-computer interaction function:

[0128] Challenge: How to implement rich and easy-to-use human-computer interaction functions is a challenge.

[0129] Solution: Adopt modern UI / UX design principles and methods to guide the design and implementation of human-computer interaction functions. At the same time, we can learn the human-computer interaction functions of other successful visualization tools and customize and optimize them in combination with user needs and feedback.

[0130] (4) Performance optimization:

[0131] Challenge: When dealing with large-scale data, how to ensure the real-time performance and response speed of the visualization tool is a challenge.

[0132] Solution: Adopt efficient data processing algorithms and visualization technologies to optimize performance. At the same time, distributed computing and parallel processing technologies can be used to accelerate the data processing and visualization processes.

[0133] In summary, the data visualization tool based on three-dimensional parallel scatter plots and human-computer interaction has broad application prospects in the field of data analysis and visualization. Through detailed steps and continuous optimization processes, we can create a visualization tool with a good user experience and practical value. At the same time, in the face of challenges in the development process, it is necessary to continuously explore and innovate solutions to promote the continuous development and progress of visualization technologies.

[0134] Furthermore, in the current distribution network system, the network is very complex and involves three or more switches. If the system is set up and calculated according to the principle of setting one switch at a level, the time-limited disconnection protection in the subsequent power distribution system will lose its own effect. Therefore, it is necessary to divide the time-limit fault protection into three levels according to the actual installation location and the nature of the connected load to ensure the effective coordination of the time limit and make the protection action within the scope of relay protection more selective.

[0135] S3: According to the analysis result, control the relay protection device to perform the protection action.

[0136] Perform current quick-break protection and overcurrent protection.

[0137] The current quick-break protection includes, and the setting calculation is expressed as:

[0138]

[0139] Among them, represents the primary value of the current quick break. represents the maximum three-phase short-circuit current on the low-voltage side of the transformer. represents the reference current of the voltage level where the line is located. represents the reliability coefficient, and the total value range is 1.2~1.3. represents the positive-sequence short-circuit impedance value under the maximum operating mode of the system. represents the positive-sequence impedance from this line to the outlet position of the next switch.

[0140] When there is only one transformer at the end of the line, the differential protection is the active protection method. The overall whole line is realized according to the fixed value of the differential protection. If the current reaches the fixed value of the differential protection, the quick-break protection is started; the fixed value of the differential protection is expressed as:

[0141]

[0142] Among them, The value range is 1.3~1.4; represents the maximum current limit of the relay.

[0143] To avoid the maximum load current of the switch during normal operation, set the overcurrent protection principle and ensure the sensitivity of the switch line during normal operation. The setting principle is expressed as:

[0144]

[0145] Among them, The value range is 1.15~1.25, represents the return coefficient, and the value is 0.85, Represents the self-starting coefficient of the motor, with a value range of 1.5 to 2.5, Represents the maximum load current at this stage.

[0146] The sensitivity verification of the switch circuit includes that the sensitivity coefficient of the line below 20 km is not less than 1.5. The sensitivity coefficient of the line between 20 and 50 km is not less than 1.4. The sensitivity coefficient of the line above 50 km is not less than 1.3. When a fault occurs in an adjacent line, the maximum sensitivity is not less than 1.2.

[0147] It should be noted that the core of this method is to accurately set the relay protection device according to the actual operation conditions of the distribution network and line parameters to ensure that faults can be quickly and accurately eliminated when they occur, protecting the safety of equipment and systems. The setting process usually includes the calculation, verification, and adjustment of protection setting values to ensure that the action characteristics of the relay protection device match the operation mode of the distribution network.

[0148] Based on the distribution network, detailed line parameter measurements and fault analyses were carried out, and the relay protection device was optimized according to the analysis results. Specific measures include adjusting the setting value of overcurrent protection and adding directional protection. After optimization, the fault elimination speed of the distribution network has been significantly improved, the power supply reliability has been greatly enhanced, and the equipment damage rate has also been greatly reduced.

[0149] In a distribution network with large load variations, the control method based on the relay protection setting value of the line can adjust the protection setting value according to the actual situation to ensure the accurate operation of the relay protection device at different load levels. For a distribution network with severely aged lines, this method can improve the accuracy and speed of fault elimination, reduce the risk of equipment damage and power outages, by measures such as adding directional protection. In a distribution network with a complex network structure, this method can comprehensively consider the mutual influence and cooperation relationship of each line to ensure that the relay protection device can work correctly during a fault, avoiding misoperation or refusal.

[0150] Compared with other control methods, the control method based on the relay protection setting of the line has the following advantages: (1) High precision: It can accurately calculate the settings according to the actual operation conditions of the distribution network and line parameters, ensuring that the action characteristics of the relay protection device match the operation mode of the distribution network and improving the accuracy of fault troubleshooting. (2) Good flexibility: This method can adapt to changes in different load levels, line aging, and complex network structures, and ensure the safe and stable operation of the distribution network by adjusting protection settings and other measures. (3) Strong reliability: The optimized relay protection device is accurate and reliable, which can effectively reduce the risk of equipment damage and power outages and improve the power supply reliability of the distribution network.

[0151] In summary, the operation control method of the distribution network side relay protection equipment based on the line relay protection setting is an effective and reliable control means. Through accurate setting calculation and adjustment measures, the accurate operation of the relay protection device during a fault can be ensured, protecting the safe and stable operation of the equipment and the system. At the same time, this method also has the advantages of good flexibility and strong reliability, and is applicable to different load levels, line aging, and changes in complex network structures. Through the above process, the instantaneous overcurrent protection and overcurrent protection of the distribution network side relay protection equipment are realized, and the operation control of the distribution network side relay protection equipment is completed.

[0152] In the above embodiments, there is also a monitoring system for distribution network relay protection equipment based on intelligent simulation, specifically:

[0153] A simulation model module is established to establish a simulation model of the relay protection equipment and analyze the operation status of the relay protection equipment according to the simulation model.

[0154] A visualization module visualizes the analysis results based on a three-dimensional parallel scatter plot in combination with human-computer interaction.

[0155] An execution protection action module controls the relay protection device to execute a protection action according to the analysis results.

[0156] The computer device can be a server. The computer device includes a processor, a memory, an input / output interface (Input / Output, abbreviated as I / O), and a communication interface. Among them, the processor, the memory, and the input / output interface are connected through a system bus, and the communication interface is connected to the system bus through the input / output interface. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program, and a database. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The database of the computer device is used to store the data cluster data of the power monitoring system. The input / output interface of the computer device is used to exchange information between the processor and external devices. The communication interface of the computer device is used to communicate with external terminals through a network connection. When the computer program is executed by the processor, it realizes a monitoring method for distribution network relay protection equipment based on intelligent simulation.

[0157] Those of ordinary skill in the art can understand that all or part of the processes in the methods of the above embodiments can be completed by instructing relevant hardware through a computer program. The computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above methods. Among them, any reference to a memory, database, or other medium used in the embodiments provided in the present application can include at least one of non-volatile and volatile memories. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetoresistive random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM), etc. The databases involved in the embodiments provided in the present application can include at least one of relational databases and non-relational databases. Non-relational databases can include distributed databases based on blockchain, etc., without limitation. The processors involved in the embodiments provided in the present application can be general-purpose processors, central processors, graphics processors, digital signal processors, programmable logic devices, data processing logics based on quantum computing, etc., without limitation.

[0158] Embodiment 2. Refer to Figures 5 to 8 , which is an embodiment of the present invention, provides a method and system for monitoring distribution network relay protection equipment based on intelligent simulation. In order to verify the beneficial effects of the present invention, scientific demonstration is carried out through simulation experiments.

[0159] Taking the urban power grid as the experimental object, the urban power grid is mainly 110 kV and above, covering 16 districts of the whole city, with an area of 16,400 square kilometers and a large power supply scope. By 2021, there are 580 substations in the city's power grid, with substations above 110 kV, a substation capacity of 144 million KVA, and a line length of 10,500 kilometers. There are many relay protection devices on the distribution side of the urban power grid. When faults such as overvoltage and short circuit occur in the urban power grid, they are responsible for timely protecting the distribution side devices such as the regional power grid. This platform is used to monitor the operation of relay protection equipment on the distribution side of the main power grid, and the actual application effect of this platform is verified.

[0160] Taking the regional power grid of this city as the experimental object, a single - end double - line system is established, and the effectiveness of the relay protection equipment simulation model established on this platform is verified. The single - end double - line system of the experimental object is as Figure 5 shown.

[0161] As Figure 5 shown, the test system is a single - end power supply 110 kV single - loop secondary transmission line. The distance protection of lines AB and BC is installed on the circuit breakers of their respective lines, serving as the main protection of this line and the backup protection of the next line. A, B, and C respectively represent three phases. The parameters of other components are: S is the power supply, T1 is the step - up transformer, T2 is the step - down transformer, the line voltage of the voltage source is 10.5 kV, the internal resistance is 0.001 + j0.0157 Ω, the transformer capacity is 31.5 MVA, the conversion impedance of the high - voltage side is 1.86 + j118.6 Ω, and the lengths of lines AB and BC are 120 kilometers. Among them, 121 kV includes a certain amount of power loss, and the normal operating voltage is 110 kV.

[0162] The operation monitoring platform for relay protection equipment on the distribution network side should adopt advanced Internet technology, cloud computing, automation technology, and sensing technology to achieve 24 - hour uninterrupted monitoring. The system network architecture mainly includes a monitoring center, relay protection devices, transformers, mobile communication networks, cloud service layers, and monitoring layers, etc. The monitoring center is equipped with high - performance computers, servers, and storage devices, as well as professional monitoring software for real - time data display and analysis, and providing fault warning and alarm functions.

[0163] The relay protection device should be configured to cooperate with the circuit breaker protection at the outlet of the substation line, including the protection of currents I, II, and III. The current I - segment protection should cooperate with the protection on the secondary side of the transformer to prevent the short - circuit current from damaging the transformer. The current II - segment protection should set appropriate current setting values and time setting values to ensure that the fault current can be quickly cut off when a fault occurs. As the backup protection, the current III - segment protection should set a longer action time limit to ensure that it can still play a role when the current I - segment and II - segment protections fail. The experimental parameter configuration table is shown in Table 1.

[0164] Table 1. Basic parameter configuration table for experiments

[0165] To verify the monitoring ability of the relay protection equipment platform on the grid side, the relay protection equipment of section AB in a single - end two - wire system was taken as the experimental object. A short - circuit fault was set in the test system, and this method was used to monitor the relay protection equipment. The current and voltage monitoring data of the relay protection device were collected by the relay protection device, which could monitor the changes of voltage and current in real time and record the data. The acquisition frequency was relatively high, collecting data every 0.2 seconds for 0.2 seconds, reaching a peak of 0.4 seconds. The data was continuously collected in a short period. The voltage and current monitoring results are as Figure 6 shown.

[0166] Through in - depth analysis of Figure 6 , we can more clearly understand the changes in current and voltage in the relay protection equipment. From the overall trend observed, the current and voltage fluctuate regularly over time, indicating that the equipment is operating normally without any abnormalities. However, at the time point of 0.6 seconds, the current and voltage waveforms suddenly become distorted. Specifically, the voltage waveform shows a disorderly fluctuation trend with a significant change range, while the current waveform suddenly transitions to a straight line. This distortion phenomenon usually indicates an abnormality, which may suggest a fault or irregular state inside the equipment. Therefore, this platform can effectively monitor the changes in current and voltage in the relay protection equipment, showing a commendable monitoring effect.

[0167] In this paper, this platform was used to monitor the status of the relay protection equipment in a single - end two - wire system when a grounding fault occurred in the relay protection equipment of section AB. The state change processes of the relay protection equipment in sections AB and BC are shown in Table 2 and Table 3 respectively.

[0168] Table 2. Status change process of distance protection for line BC

[0169] Table 2 outlines the state transition and duration of the distance protection of line BC. By observing the changes in the line voltage and current values, it is obvious that a grounding fault occurred on line BC at 0.8 seconds and was cleared at 1.012 seconds. The fault was located at half of the BC line. The hybrid automaton model of the directional impedance relay on line BC detected that the measured short - circuit impedance was lower than the preset impedance value of the protection zone, indicating a transition from the idle state to the ready state at 0.8 seconds. Subsequently, after 0.012 seconds of simulation steps, the system detected that the stuck signal had entered the stuck state, resulting in the blocking of the third - stage protection of line BC and preventing its operation.

[0170] During the experiment, ZH-2 fault recorders were installed on both sides of the single-ended two-wire system, and four fault points, F1, F2, F3, and F4, were set. First, it was artificially set to point F2, with an occurrence time of 0.2 seconds and a duration of 0.1 seconds. Then it was reset to 0.97 seconds, and the time period for recording the fault waveform was 0.15 seconds to 2 seconds. Then the fault monitoring program of the relay protection device was run on the platform, including the protection action of Ganliu Branch Substation, the drive channel number 8#1-1, the distance protection of the second section of Ganliu Branch not working, and the overcurrent relay not working properly. At the same time, the exact time of the fault occurrence was recorded as 13:05:44. In addition, the fault diagnosis result part clearly stated that the fault type was a-phase fault, pointed out the fault switching situation where the overcurrent relay did not operate, evaluated the switching action, and considered that there was a fault in the overcurrent relay. The test results of the relay protection device fault monitoring are shown in Table 3.

[0171] Table 3 Change process of the distance protection of line AB

[0172] Table 3 details the state transition and duration of the distance protection of line AB. The fault is located at the midpoint of line BC. The hybrid automaton model of the directional impedance relay on line AB detects that the short-circuit impedance is lower than the preset impedance value of protection section 3, triggering a transition from the idle state to the waiting 2 state at 0.8 seconds. Subsequently, after a delay of 0.03 seconds, it enters the ready state. Then, after a simulation step of 0.022 seconds, it transitions to the traveling state. After receiving the trip signal, the circuit breaker operates to disconnect the faulty lines AB and BC. The three-stage protection mechanism of line AB acts as a backup protection to ensure that the fault on line BC is isolated.

[0173] During the experiment, ZH-2 fault recorders were installed on both sides of the single-ended double-link line system, and 4 fault points such as F1, F2, F3, and F4 were set. First, an a-phase ground fault was manually set at point F2, with an occurrence time of 0.2 seconds and a duration of 0.1 seconds. Then a reclosing operation was performed, and the reclosing time was 0.97 seconds. The time period for recording the fault waveform was selected as 0.15 seconds to 2 seconds. Then, the fault monitoring program of the relay protection device was run on the platform, and the recorded results are shown in Table 3. Table 3 provides a detailed list of real-time information, including the substation name Ganliu Branch Station, the drive channel number 8#1-1, the distance protection fault of the second section of Ganliu Branch, and the overcurrent relay fault. The exact time of the fault occurrence was recorded as 13:05:44. In addition, the fault diagnosis result part clearly identified the fault type as a-phase ground fault, pointed out the fault switching situation where the overcurrent relay could not operate, and evaluated the switch operation, considering that there was a fa in the overcurrent relay. The fault monitoring test results of the relay protection device are shown in Table 4.

[0174] Table 4 Fault Monitoring Test Results of Relay Protection Equipment

[0175] As can be seen from the analysis of Table 4, when a phase-to-phase ground fault occurs in the single-ended double-line system line, the overcurrent relay does not respond as expected. This refusal to move results in the inability to protect the line in a timely manner, making it unsafe during a fault. The judgment result of the switch operation also shows that the overcurrent protection device cannot work properly in this situation, further confirming the fault of the protection device in the fault state. The results show that the platform can effectively monitor the operating status of the relay protection device, detect and diagnose possible faults in a timely manner. This is of great significance for ensuring the stability and safety of the power system. At the same time, the application of this platform also helps to improve the overall performance and reliability of power equipment, providing strong support for the development of the power industry. In addition, through the application of this platform, power workers can obtain the working status information of the relay protection equipment in real time, take corresponding measures in a timely manner, prevent and handle possible faults. This not only reduces the possibility of equipment failure, but also shortens the fault repair time, providing strong support for the stable operation of the power system.

[0176] To verify the control ability of the platform for relay protection devices, the regional power grid was used as the experimental object. In this regional distribution network, the lines are mainly composed of 7 ring networks. According to the location of the ring main unit and the nature of the received load, the 7 ring main units are divided into two levels, among which 1, 2, 3, and 5 are secondary switches, and 6, 7, and 8 are tertiary switches. In the distribution network composed of the seven-ring network of the regional power grid, verification benchmarks and comparison standards were established. These benchmarks include: whether the platform can accurately and reliably remotely control the relay protection devices of each level of ring main unit cabinets, monitor their working status in real time, and send early warning or alarm information in a timely manner when a fault is detected. It was verified that the platform has obvious advantages in terms of function, performance, and stability, etc. To achieve this goal, the ring main unit cabinets were adjusted through this platform. A comprehensive test analysis was carried out on the platform to ensure that it can play a good monitoring role in actual applications, improve the reliability and safety of the power system. The control test results of the relay protection device are shown in Table 5.

[0177] Table 5 Control Test Results of Relay Protection Equipment

[0178] It can be clearly seen from the data in Table 5 that in the first and second stages of overcurrent, the main values of the primary, secondary, and tertiary switches gradually decrease. This indicates that the control settings of the power grid relay protection equipment through this platform can effectively reduce the primary values in different overcurrent stages. This optimization not only helps to protect power grid equipment but also reduces the risk of potential power accidents to a certain extent. In addition, as the switch level increases, the time limit for setting control of the primary value in the power grid gradually decreases. This shows that the platform proposed in this paper has the characteristic of fast response when controlling relay protection equipment. This fast response ability is particularly important in dealing with sudden power outages, significantly improving the stability and security of the power system. In summary, through the setting control of the relay protection equipment in the power grid by this platform, the primary values in different overcurrent stages are optimized, showing fast response characteristics. This fully verifies the excellent control ability of the platform described in this paper and provides strong support for the development of the power industry.

[0179] In this paper, when the platform visualizes the monitoring results of relay protection equipment, Spark automatically decomposes the instructions into local tasks for scheduling and processing, which does not involve parallel data computing in the Spark cluster. Therefore, we only analyzed the efficiency of visual display based on three-dimensional parallel scatter plots under different data volumes, and the time threshold for device visual display is 16 s. The test results are as Figure 7 shown.

[0180] From Figure 7 the analysis, it can be clearly seen that the visualization display time of the platform presented in this paper increases with the increase in data volume. However, even with a large amount of data volume, the visual display time of the platform still remains below 16 seconds. This shows that the platform has good visual display ability for relay protection equipment.

[0181] To further verify the visual display ability of this platform, the relay protection devices of Lines I, II, III, and IV are used as experimental objects, and the platform is used to visually display their line currents. The display results are as Figure 8 shown.

[0182] Through in-depth analysis of Figure 8 , it can be seen that this method not only successfully captures and displays the current waveforms of relay protection devices on different lines in the power grid but also breaks through the limitations of traditional methods to a certain extent, enabling these complex current changes to be presented to electrical workers in an intuitive and understandable way. Specifically, the current waveforms in the figure record the continuous changes of current over time, and the subtle differences in waveforms on each line reflect the current operating states of the lines. By comparing the current waveforms on different lines, abnormal or potential risk points can be quickly identified, and corresponding measures can be taken in a timely manner to ensure the safe and stable operation of the power grid.

[0183] In summary, the application of this method enables the platform to have good visual display capabilities. It is not only a data display tool but also a powerful decision-making system. Through these accurate and intuitive visual information, power workers can have a more comprehensive understanding of the operation of the power grid, thus making more scientific and reasonable decisions. The monitoring method proposed in this paper not only provides a new and efficient monitoring method for power workers but also provides strong technical support for the sustainable development of the entire power industry. With the continuous progress of technology and the continuous deepening of applications, this visual display mode will play an increasingly important role in the power industry and make greater contributions to the safe and stable operation of the power grid.

[0184] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the spirit and scope of the technical solutions of the present invention, and they should all be covered within the scope of the claims of the present invention.< / vector>

Claims

1. A distribution network relay protection equipment monitoring method based on intelligent simulation, characterized in that: include: Establish a simulation model of relay protection equipment and analyze the operating status of the relay protection equipment based on the simulation model; Based on three-dimensional parallel scatter plots and combined with human-computer interaction, the analysis results are visualized; According to the analysis results, control the relay protection device to perform protection actions; The establishment of the simulation model of the relay protection device includes establishing a state diagram according to the states of the overcurrent relay and the impedance protection relay, respectively, indicating the fault condition of the relay by a connecting line with an arrow, and the direction of the arrow indicates the relay state transition caused by the fault condition, thereby establishing the simulation model of the overcurrent protection and the simulation model of the impedance protection device; Analyzing the operating state of the relay protection device according to the simulation model includes completing the state conversion of the simulation model by monitoring the fault during the simulation process of the relay protection device on the distribution network side; The fault monitoring includes collecting real-time operating status information of the equipment and diagnosing operating faults of the relay protection equipment on the distribution network side using a support vector machine; The real-time operation status information includes calculating the three-phase current on the high-voltage side according to the current in different directions of the high-voltage side diagnosis transformer; assuming that the resistances of the three-phase windings A, B, and C and the neutral point are resistance one, resistance two, resistance three, and resistance four, respectively, performing weighted summation of the current measurement values ​​of each resistor in unit time and dividing by 4 to obtain the measurement value of each phase current; ,in, represents the measured value of the phase current a, represents the measured value of phase current b, represents the measured value of the phase current c; Indicates in unit time Current measurement value of internal resistance one, Indicates in unit time Current measurement value of internal resistor 2, Indicates in unit time Current measurement value of internal resistance three, Indicates in unit time Current measurement value of internal resistor 4; Balance coefficient It is expressed as: ,in, Indicates the average value of three-phase current.

2. The distribution network relay protection equipment monitoring method based on intelligent simulation according to claim 1, characterized in that: Analyzing the operating state of the relay protection device according to the simulation model also includes, in the relay protection simulation model, determining whether the system has a fault by analyzing the signal action state; when no fault occurs, the system fault is determined to be a protection misoperation; when a fault occurs, the system action is determined to be a protection rejection; Operate and misoperate the circuit breaker, determine whether the circuit is tripped, and obtain the misoperation status set of the circuit breaker ; Based on the support vector machine method, the fault samples of the relay protection device are classified. In the training sample set, it is judged whether the samples are linearly separable. The classification decision function of the optimal hyperplane is expressed as: ,in, The value of the classification decision function representing the optimal hyperplane; represents a symbolic function; Represents the training weights of the vector machine; Represents the classification constant value for training; represents the inner product of weights; Classify according to fault samples, separate all samples, and reduce misclassification; Under the constraint of the inequality, each sample determines the reflection value according to the actual relaxation factor, and the discriminant function of the generalized optimal classification surface is expressed as: ,in, represents the value of the discriminant function; n represents the number of samples; Represents the transformation parameters of the feature; when , indicating that the discrimination result of the sample under the algorithm is 1, indicating that the classification surface has a fault. , indicating that the discrimination result of the sample under the algorithm is 0, indicating that the classification surface has no fault.

3. The distribution network relay protection equipment monitoring method based on intelligent simulation according to claim 2, characterized in that: The method of visualizing the analysis results based on three-dimensional parallel scatter plots and combining human-computer interaction includes acquiring real-time data from the online monitoring system of power equipment using an RDD-type acquisition method, extracting equipment status information, forming elastically distributed data sets RDDs, and constructing a data structure of a specified type; Parse the data set according to data type and split it into a list of cluster numbers and a list of data point sets. After the data is classified, assign a color to each cluster number and construct a coloring list. Using the three-dimensional scatter method, the data point set is combined with the coloring list to generate a three-dimensional parallel scatter plot, which presents the distribution characteristics of the power equipment status; The command method of the chart class is used to add human-computer interaction operations to support the decomposition and display of the relationship between each attribute and time; the visualization results are displayed through the openChart method.

4. The distribution network relay protection equipment monitoring method based on intelligent simulation according to claim 3 is characterized in that: According to the analysis result, controlling the relay protection device to perform protection actions includes performing current fast circuit breaking protection and overcurrent protection; The current rapid circuit-breaking protection includes: dividing the product of the reliability coefficient and the maximum three-phase short-circuit current on the low-voltage side of the transformer by the sum of the positive-sequence short-circuit impedance value under the maximum operation mode of the system and the positive-sequence impedance from the line to the next switch outlet position, to obtain the primary value of the current rapid circuit-breaking; When there is only one transformer at the end of the line, the differential protection is an active protection mode; the entire line is realized according to the fixed value of the differential protection. If the current reaches the fixed value of the differential protection, the fast circuit breaker protection is started; the fixed value of the differential protection is expressed as: ,in, The value range is 1.3~1.4; Indicates the maximum current limit of the relay.

5. The distribution network relay protection equipment monitoring method based on intelligent simulation according to claim 4 is characterized in that: The overcurrent protection includes setting an overcurrent protection principle to avoid the maximum load current of the switch during normal operation, and ensuring the sensitivity of the switch circuit during normal operation. If the current reaches a fixed value of the overcurrent protection, the overcurrent protection is started; during normal operation, the fixed value of the overcurrent protection is expressed as: ,in, Value range 1.15~1.25, Indicates the return coefficient, the value is 0.85, Indicates the self-starting coefficient of the motor, ranging from 1.5 to 2.

5. Indicates the maximum load current in this stage; The sensitivity verification of the switching line includes: the sensitivity coefficient of the line below 20km is not less than 1.5; the sensitivity coefficient of the line between 20~50km is not less than 1.4; the sensitivity coefficient of the line above 50km is not less than 1.3; when a fault occurs in the adjacent line, the maximum sensitivity is not less than 1.

2.

6. A distribution network relay protection equipment monitoring system based on intelligent simulation using the method according to any one of claims 1 to 5, characterized in that: Establish a simulation model module, establish a simulation model of the relay protection equipment, and analyze the operating status of the relay protection equipment based on the simulation model; The visualization module visualizes the analysis results based on three-dimensional parallel scatter plots and combines human-computer interaction; The protection action execution module controls the relay protection device to execute the protection action according to the analysis results.

7. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 5 are implemented.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 5 are implemented.

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