Abnormality diagnosis method for secondary equipment of power system

Abstract

The invention provides an abnormality diagnosis method for secondary equipment of a power system, and relates to the technical field of power equipment fault detection, and the method comprises the steps: constructing an analog simulation system for simulating the state of the secondary equipment of the power system; acquiring simulation data for simulating the real environment of the power secondary equipment from the power secondary equipment; preprocessing the simulation data to obtain preprocessed simulation data; inputting the preprocessed simulation data into an analog simulation system, and identifying the operation state of the power secondary equipment; and displaying and processing the abnormal state of the power secondary equipment according to the operation state of the power secondary equipment identified by the analog simulation system. According to the scheme, the maintenance efficiency of secondary side operation and maintenance of the power system can be improved, and meanwhile reliable operation of power secondary equipment is guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of power equipment fault detection, and in particular to an abnormality diagnosis method for secondary equipment of a power system. Background Art

[0002] Power secondary equipment is equipment that is not directly connected to electric energy. It mainly includes measuring meters, insulation monitoring devices, control and signal devices, relay protection and automatic devices, DC current equipment, integrated automation equipment, etc. Power secondary equipment is mainly used to monitor, measure, control, protect, adjust and communicate with other equipment in the power system. For example, it can monitor the current, voltage, power, etc. of the circuit to provide a basis for decision-making for operation and maintenance personnel; for example, through secondary equipment, it can quickly cut off the power supply or perform other necessary operations when a circuit fails to prevent the accident from expanding. Therefore, the normal operation of the secondary equipment of the power system is crucial, and it is necessary to diagnose and warn of faults.

[0003] Abnormal diagnosis and early warning of secondary equipment in power systems refers to the early warning and diagnosis of whether a fault will occur under certain conditions by analyzing and processing certain historical data based on the real-time operation and maintenance data of secondary equipment. At present, the commonly used abnormal diagnosis methods for power secondary equipment are mainly expert systems, rough sets, Petri nets, etc. However, the existing abnormal diagnosis schemes for secondary equipment in power systems generally have the problem of lag, that is, it is difficult to timely discover the existing or possible faults of power secondary equipment before the abnormality occurs, and thus it is difficult to improve the efficiency of the secondary side operation and maintenance of the power system and ensure the reliable operation of the secondary power equipment. Summary of the invention

[0004] In view of this, in order to address the above shortcomings, it is necessary to propose an abnormal diagnosis method for secondary equipment in power systems to improve the maintenance efficiency of secondary side operation and maintenance of power systems and ensure the reliable operation of secondary power equipment.

[0005] In a first aspect, the present invention provides a method for diagnosing abnormality of secondary equipment in a power system, comprising: Construct a simulation system for simulating the status of power secondary equipment; Acquiring simulation data from the power secondary equipment for simulating the real environment of the power secondary equipment; Preprocessing the simulation data to obtain preprocessed simulation data; Inputting the pre-processed simulation data into the simulation system to identify the operating status of the power secondary equipment; According to the operating status of the power secondary equipment identified by the simulation system, the abnormal status of the power secondary equipment is displayed and processed.

[0006] Preferably, the simulation system for simulating the state of the secondary power equipment comprises: Construct a typical substation secondary equipment model; the typical substation secondary equipment includes: electrical quantity protection and non-electrical quantity protection of the main transformer protection device, line protection device, busbar protection and standby automatic switching; at least construct a three-dimensional model of the LCD display, indicator light, control handle, pressure plate status switch pressure plate, terminal block, and secondary wiring in the protection device to achieve a panoramic simulation and display of the secondary equipment; After the substation secondary equipment model is built, various data links are opened, and various data of the secondary equipment in the substation are adapted to the substation secondary equipment model.

[0007] Preferably, the simulation data obtained from the power secondary equipment includes: operating status data, electrical parameters and control signals of the power secondary equipment.

[0008] Preferably, the preprocessing of the simulation data includes: For missing values ​​in the simulation data, the missing values ​​are filled by using the mean value of the period before the missing value; At the same time, the 3sigma principle is used to eliminate outliers in the simulation data; The simulation data after missing value filling and outlier removal are normalized.

[0009] Preferably, the step of inputting the pre-processed simulation data into the simulation system to identify the operating status of the power secondary equipment includes: Determine the switch status based on the multimeter; Compare the protection winding and the measurement winding to determine whether there is a sampling plug-in failure; Determine whether there is a fault in the circuit caused by an error in the soft pressure plate setting or the setting value setting, which leads to abnormal current or voltage; Compare the voltages at different intervals with the bus voltage horizontally to determine whether there is any abnormality in the secondary virtual connection of the bus voltage.

[0010] Preferably, the displaying of the abnormal state of the power secondary equipment according to the operating state of the power secondary equipment identified by the simulation system includes: After the protection device trips, the action message collection and differential current abnormality display are performed; When an abnormality occurs during the tripping response process of the protection device, the fault filter starts to disconnect the switches on both sides of the transformer, records the differential current or tripping action related data, and displays it in a pop-up window.

[0011] Preferably, the processing of the abnormal state of the power secondary equipment according to the operating state of the power secondary equipment identified by the simulation system includes: If the soft pressure plate is set incorrectly, the differential protection soft pressure plate is used to exit; If the set value is set incorrectly, the differential current setting method is adopted to deal with it; For the secondary false connection of busbar secondary voltage, simulate the false connection of the upper end of busbar voltage circuit breaker from PT to PT terminal box, middle circuit breaker, voltage parallel and protection screen busbar voltage circuit breaker, and use a multimeter to measure and troubleshoot; In case of sampling plug-in failure, use a clamp ammeter to measure the sampling value and simulate replacing the plug-in.

[0012] Preferably, for the secondary virtual connection of the control loop, the processing of the abnormal state of the secondary power equipment also includes: Check the contact surface and clean it; Tighten the screws to ensure that the terminal screws are tight; Pull on the cables to determine if they are loose and retighten or connect with an appliance connector if they are loose.

[0013] In a second aspect, the present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed in a computer, causes the computer to execute any of the methods described in the first aspect.

[0014] In a third aspect, the present invention provides a computing device, including a memory and a processor, wherein executable code is stored in the memory, and when the processor executes the executable code, any method described in the first aspect is implemented.

[0015] It can be seen from the above technical scheme that in the abnormal diagnosis method of the secondary equipment of the power system provided by the embodiment of the present invention, first consider constructing a simulation system for simulating the state of the secondary power equipment, then obtain simulation data for simulating the real environment of the secondary power equipment from the secondary power equipment, and pre-process the simulation data; further, input the obtained pre-processed simulation data into the simulation system, identify the operating state of the secondary power equipment, and then display and process the abnormal state of the secondary power equipment based on the operating state of the secondary power equipment identified by the simulation system. It can be seen that the present scheme constructs a simulation system, which can simulate the state of the secondary power equipment by inputting the data of the secondary power equipment into the simulation system before the abnormality occurs or at the early stage of the abnormality, and then determine the existing abnormality by analyzing the simulation results. In this way, not only can the abnormality of the secondary power equipment be discovered in time and the reliable operation of the secondary power equipment be guaranteed, but also the workload of manual inspection is greatly reduced, and the efficiency of the secondary side operation and maintenance of the power system can be greatly improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1A flowchart of a method for diagnosing abnormality of secondary equipment in a power system provided by an embodiment of the present invention.

[0017] Figure 2 This is the network diagram of the simulation system structure. DETAILED DESCRIPTION

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0019] like Figure 1 As shown, the present invention provides a method for diagnosing abnormality of secondary equipment in a power system, which may include the following steps: Step 101: constructing a simulation system for simulating the state of power secondary equipment; Step 102: Acquire simulation data for simulating a real environment of the power secondary equipment from the power secondary equipment; Step 103: preprocessing the simulation data to obtain preprocessed simulation data; Step 104: inputting the pre-processed simulation data into the simulation system to identify the operating status of the power secondary equipment; Step 105: Display and process the abnormal state of the secondary power equipment according to the operating state of the secondary power equipment identified by the simulation system.

[0020] In this embodiment, first consider building a simulation system for simulating the state of secondary power equipment, then obtain simulation data for simulating the real environment of secondary power equipment from the secondary power equipment, and preprocess the simulation data; further, input the obtained preprocessed simulation data into the simulation system, identify the operating state of the secondary power equipment, and then display and process the abnormal state of the secondary power equipment based on the operating state of the secondary power equipment identified by the simulation system. It can be seen that the simulation system constructed by this scheme can simulate the state of the secondary power equipment by inputting the data of the secondary power equipment into the simulation system before the abnormality occurs or at the early stage of the abnormality, and then determine the existing abnormality by analyzing the simulation results. In this way, not only can the abnormality of the secondary power equipment be discovered in time and the reliable operation of the secondary power equipment be guaranteed, but also the workload of manual inspection is greatly reduced, and the efficiency of the secondary side operation and maintenance of the power system can be greatly improved.

[0021] For step 101, a simulation system for simulating the state of a secondary power device is constructed; In this step, when building the simulation system, consider the digital mapping technology, combined with artificial intelligence algorithms and digital-analog fusion technologies. Based on artificial intelligence algorithms, the real-time current of the substation secondary equipment is monitored and the development trend is predicted to realize the intelligent early warning function, which can reduce the probability of sudden failures. By improving the digital-analog fusion capability, breaking the data island, and strengthening operation and maintenance simulation training, the operation and maintenance efficiency and the digital level of the team can be significantly improved, promoting the high-quality development of the power grid.

[0022] Specifically, the simulation system is mainly constructed to construct a typical substation secondary equipment model, which can mainly include electrical quantity protection (set A, set B) and non-electrical quantity protection (set A, set B) of the main transformer protection device, line protection device (set A, set B), busbar protection (set A, set B) and standby automatic switching; among them, the protection device needs to construct a three-dimensional model of elements such as LCD display, indicator light, control handle, pressure plate status switch pressure plate, terminal block, secondary wiring, etc., to achieve a panoramic simulation and display of secondary equipment; after the substation secondary equipment model is built, the secondary equipment data in the substation is investigated, various data links are opened, and various data of the secondary equipment in the substation are adapted and combined with the substation secondary equipment model to achieve a more comprehensive, timely and accurate status perception and digital-analog information fusion of the substation secondary equipment.

[0023] The constructed simulation system mainly depends on the topology and data transmission information of the plant and master stations. Figure 2 As shown, the voltage, current, power, power factor, oil temperature, winding temperature, alarm signal, switch opening and closing status and other telemetry and telesignaling of the telecontrol device in zone I of the plant side are transmitted to the main equipment monitoring host in zone I of the main station through the data network; the relevant action information, alarm information and fault briefing information of the fault recording of the relay protection device of the protection substation in zone II of the plant side are transmitted to the main equipment monitoring host in zone II of the main station through the data network; the SCADA front-end server in zone I of the main station and the data server in zone II are connected and aggregate the telemetry, telesignaling and relay protection data of zones I and II, and transmit them to the data server in zone IV through forward isolation; a secondary equipment simulation application server is deployed in the information management zone IV to receive and process data, and each host of the secondary equipment simulation system realizes data collection by sharing data on the data network, and combines the data with the secondary equipment model for simulation.

[0024] For step 102, simulation data for simulating a real environment of the power secondary equipment is obtained from the power secondary equipment; In this step, the collected data include the operating status, electrical parameters and control signals of the equipment, etc. These data are of great significance for analyzing the performance of the equipment and verifying the accuracy of the prediction results. After completing the data collection, the simulation data is cleaned, sorted and analyzed to extract useful information. Specifically, the collected data can include: telemetry values ​​of current and voltage, switch status, protection setting value, which can be used to simulate the real environment. In addition, these data can also be displayed on the device display interface through human-computer interaction, and employees can directly view and understand the meaning and function of each data.

[0025] In step 103, the simulation data is preprocessed to obtain preprocessed simulation data; This step is used to achieve data integrity and improve data accuracy. When preprocessing the simulation data, the missing values ​​in the simulation data can be filled with the mean value of the period before the missing value; at the same time, the 3sigma principle is used to remove the abnormal values ​​in the simulation data to remove the data generated due to sensor acquisition errors and other reasons; then the simulation data after missing value filling and abnormal value removal is normalized. In addition, in one embodiment, it is also possible to consider using a dynamic baseline prediction algorithm to automatically aggregate the data to reduce the amount of data processing and improve the operating efficiency of the system.

[0026] For step 104, the pre-processed simulation data is input into the simulation system to identify the operating status of the power secondary equipment; This step is used to identify different operating states of secondary equipment, which may include: The switch status is determined based on a multimeter; specifically, the switch status is determined using a multimeter, and the display value of the multimeter is observed. If it shows 0, it means that the two terminals are connected to a normally closed state, that is, the switch is closed by default; observe whether the display value of the multimeter changes to 1. If so, it means that the switch has been connected to the circuit and the switch status is normal; if the multimeter displays 1, it indicates that the switch is in an open state.

[0027] Compare the protection winding and the measurement winding to determine whether there is a sampling plug-in fault; specifically, compare the protection and measurement windings, and issue an alarm if the corresponding items differ too much. Calculate the differential current by comparing the current side and the opposite side, and also compare the three sides to calculate the differential current.

[0028] Determine whether there is a soft pressure plate setting error or a constant setting error in the circuit that causes abnormal current or voltage. For example, you can use the system's virtual multimeter tool to simulate the measurement of voltage, current and other parameters in the model to gradually narrow the scope of the abnormality.

[0029] Compare the voltages at different intervals with the bus voltage horizontally to determine whether there is any abnormality in the secondary virtual connection of the bus voltage.

[0030] For step 105, according to the operating status of the power secondary equipment identified by the simulation system, the abnormal status of the power secondary equipment is displayed and processed.

[0031] When displaying the abnormal state of the power secondary equipment according to the operating state of the power secondary equipment identified by the simulation system, it is mainly used to realize the visual display of the abnormal operation. Specifically, it can include: the collection and display of the action message after the trip (message, lighting) and the display of the differential current abnormality; it can simulate the fault conditions such as the abnormal differential current in the operation of the substation, and the response process after the protection device trips. When an abnormality occurs, the fault recording starts the switches on both sides of the transformer to disconnect. The system will first record the data related to the differential current or tripping action, and display it in a pop-up window on the interface, and connect the substation tripping recording data. After the trip, the LCD screen can display the recording diagram.

[0032] When processing the abnormal state of the power secondary equipment according to the operating state of the power secondary equipment identified by the simulation system, it mainly includes: If the soft pressure plate is set incorrectly, the differential protection soft pressure plate is used to exit; If the set value is set incorrectly, the differential current setting method is adopted to handle it; For the secondary false connection of busbar secondary voltage, simulate the false connection of the upper end of busbar voltage circuit breaker from PT to PT terminal box, middle circuit breaker, voltage parallel and protection screen busbar voltage circuit breaker, and use a multimeter to measure and troubleshoot; In case of sampling plug-in failure, use a clamp ammeter to measure the sampling value and simulate replacing the plug-in.

[0033] Furthermore, for the secondary virtual connection of the control loop, the abnormal state of the power secondary equipment is processed, which also includes: Check the contact surface and clean it; Tighten the screws to ensure that the terminal screws are tight; Pull on the cables to determine if they are loose and retighten or connect with an appliance connector if they are loose.

[0034] In this embodiment, for the abnormality of virtual connection of the secondary line of the control loop, consider checking the contact surface, cleaning the contact surface, and ensuring that there is no dust, dirt or other impurities obstructing the contact; tighten the screws, ensuring that the wiring screws are tightened, but do not use excessive force to avoid damaging the wires or terminals; check the connection, pull the wires by hand; check for looseness, if looseness is found, retighten the screws, and check again whether the connection is firm; use an electrical connector. If the cable connection is unreliable, consider using an electrical connector for connection. Electrical connectors are usually securely connected and simple and convenient to operate; test the connection. After completing the above steps, perform a circuit test to ensure that the control loop is working properly.

[0035] The abnormality diagnosis method of secondary equipment in a power system provided by the present invention has at least the following beneficial effects: (1) This solution builds a simulation system that can simulate the state of the power secondary equipment by inputting the data of the power secondary equipment into the simulation system before or at the early stage of the abnormality, and then determine the existing abnormality by analyzing the simulation results. This not only can timely detect the abnormality of the power secondary equipment and ensure the reliable operation of the power secondary equipment, but also greatly reduce the workload of manual inspections and can greatly improve the efficiency of the secondary side operation and maintenance of the power system.

[0036] (2) This solution can greatly reduce the workload of manual inspections by real-time monitoring of equipment status, while increasing the comprehensive coverage and frequency of equipment inspections. Based on artificial intelligence algorithms, this solution can realize intelligent early warning / alarm functions by monitoring the real-time current of substation secondary equipment and predicting its development trend, thereby reducing the probability of sudden failures.

[0037] (3) This solution integrates multi-source data to achieve accurate prediction of equipment status trends, remote diagnosis of abnormalities and simulation training. By improving the digital-analog integration capabilities of secondary equipment, it breaks the "data island" and improves the multi-source data aggregation and analysis capabilities. It supports the secondary equipment operation and maintenance simulation training, improves the secondary side operation and maintenance efficiency of substations, and improves the digitalization level of teams, providing effective support for the high-quality development of the company and the power grid.

[0038] The present specification also provides a computer-readable storage medium on which a computer program is stored. When the computer program is executed in a computer, the computer is caused to execute a method in any one of the embodiments in the specification.

[0039] The present specification also provides a computing device, including a memory and a processor, wherein executable codes are stored in the memory, and when the processor executes the executable codes, a method in any embodiment of the present specification is implemented.

[0040] Since the device embodiments provided by the present invention are based on the same inventive concept as the method embodiments of this specification, the specific contents can be found in the description of the method embodiments of this specification and will not be repeated here.

[0041] The modules or units in the device of the embodiment of the present invention can be combined, divided and deleted according to actual needs. The above disclosure is only the preferred embodiment of the present invention, and of course it cannot be used to limit the scope of the rights of the present invention. Those skilled in the art can understand that all or part of the processes of the above embodiment are implemented, and the equivalent changes made according to the claims of the present invention still fall within the scope of the invention.

Claims

1. A method for diagnosing abnormality of secondary equipment in a power system, characterized in that: include: Construct a simulation system for simulating the status of power secondary equipment; Acquiring simulation data from the power secondary equipment for simulating the real environment of the power secondary equipment; Preprocessing the simulation data to obtain preprocessed simulation data; Inputting the pre-processed simulation data into the simulation system to identify the operating status of the power secondary equipment; According to the operating status of the power secondary equipment identified by the simulation system, the abnormal status of the power secondary equipment is displayed and processed.

2. The abnormality diagnosis method for secondary equipment in a power system according to claim 1, characterized in that: The simulation system for simulating the state of electric secondary equipment comprises: Construct a typical substation secondary equipment model; the typical substation secondary equipment includes: electrical quantity protection and non-electrical quantity protection of the main transformer protection device, line protection device, busbar protection and standby automatic switching; at least construct a three-dimensional model of the LCD display, indicator light, control handle, pressure plate status switch pressure plate, terminal block, and secondary wiring in the protection device to achieve a panoramic simulation and display of the secondary equipment; After the substation secondary equipment model is built, various data links are opened, and various data of the secondary equipment in the substation are adapted to the substation secondary equipment model.

3. The abnormality diagnosis method for secondary equipment in a power system according to claim 1, characterized in that: The simulation data obtained from the power secondary equipment includes: operating status data, electrical parameters and control signals of the power secondary equipment.

4. The abnormality diagnosis method for secondary equipment in a power system according to claim 1, characterized in that: The preprocessing of the simulation data comprises: For missing values ​​in the simulation data, the missing values ​​are filled by using the mean value of the period before the missing value; At the same time, the 3sigma principle is used to eliminate outliers in the simulation data; The simulation data after missing value filling and outlier removal are normalized.

5. The abnormality diagnosis method for secondary equipment in a power system according to claim 1, characterized in that: The step of inputting the pre-processed simulation data into the simulation system to identify the operating status of the power secondary equipment includes: Determine the switch status based on the multimeter; Compare the protection winding and the measurement winding to determine whether there is a sampling plug-in failure; Determine whether there is a fault in the circuit caused by an error in the soft pressure plate setting or the setting value setting, which leads to abnormal current or voltage; Compare the voltages at different intervals with the bus voltage horizontally to determine whether there is any abnormality in the secondary virtual connection of the bus voltage.

6. The abnormality diagnosis method for secondary equipment in a power system according to claim 1, characterized in that: The displaying of the abnormal state of the secondary power equipment according to the operating state of the secondary power equipment identified by the simulation system includes: After the protection device trips, the action message collection and differential current abnormality display are performed; When an abnormality occurs during the tripping response process of the protection device, the fault filter starts to disconnect the switches on both sides of the transformer, records the data related to the differential current or tripping action, and displays it in a pop-up window.

7. The abnormality diagnosis method for secondary equipment in a power system according to claim 5, characterized in that: The processing of the abnormal state of the secondary power equipment according to the operating state of the secondary power equipment identified by the simulation system includes: If the soft pressure plate is set incorrectly, the differential protection soft pressure plate is used to exit; If the set value is set incorrectly, the differential current setting method is adopted to deal with it; For the secondary false connection of busbar secondary voltage, simulate the false connection of the upper end of busbar voltage circuit breaker from PT to PT terminal box, middle circuit breaker, voltage parallel and protection screen busbar voltage circuit breaker, and use a multimeter to measure and troubleshoot; In case of sampling plug-in failure, use a clamp ammeter to measure the sampling value and simulate replacing the plug-in.

8. The abnormality diagnosis method for secondary equipment in a power system according to claim 7, characterized in that: For a secondary virtual connection of the control loop, the processing of the abnormal state of the secondary power equipment also includes: Check the contact surface and clean it; Tighten the screws to ensure that the terminal screws are tight; Pull on the cables to determine if they are loose and retighten or connect with an appliance connector if they are loose.

9. A computer-readable storage medium having a computer program stored thereon, which, when executed in a computer, causes the computer to execute the method according to any one of claims 1 to 8.

10. A computing device, comprising a memory and a processor, wherein the memory stores executable codes, and when the processor executes the executable codes, the method according to any one of claims 1 to 8 is implemented.

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