Multi-dimensional collaborative test and quantitative evaluation method for hydropower station protection system

Abstract

The invention relates to a hydropower station protection system multi-dimensional collaborative test and quantitative evaluation method, and belongs to the technical field of electric power automation. Protection device information is collected, a database is established, and a device aging risk list is generated; identifying a common cause fault risk in the double configuration, and starting heterogeneous replacement type selection; constructing a prototype system based on domestic hardware and carrying out a digital simulation test; deploying an online monitoring unit, calculating a device operation health degree score and performing early warning; a reconstruction scheme is compared and selected through three-dimensional simulation, and a new screen cabinet is designed and prefabricated in a customized mode; replacing and debugging are executed in the planned power failure window, and a unified monitoring platform is accessed; and after commissioning, carrying out dynamic performance recheck test according to a plan, and continuously updating the reliability evaluation file. According to the invention, full-life-cycle closed-loop management from state evaluation, heterogeneous design, prototype verification, online monitoring, refined construction to long-term performance tracking is realized, and the reliability, safety and operation and maintenance efficiency of a hydropower station protection system are improved.

Description

Technical Field

[0001] This application relates to the field of power automation technology, and in particular to a multi-dimensional collaborative testing and quantitative evaluation method for hydropower station protection systems. Background Technology

[0002] Traditional operation, maintenance, and upgrades of hydropower station protection systems typically rely on periodic inspections and post-fault troubleshooting, lacking forward-looking and quantitative assessment methods for the aging status of equipment, configuration risks, and system-level collaborative performance. Existing technologies often focus on the functional verification of individual devices or are limited to localized upgrades, failing to take a holistic system perspective and organically coordinate and quantitatively manage multiple aspects such as condition assessment, heterogeneous design, core hardware verification, online monitoring, refined construction, and long-term performance tracking.

[0003] Specifically, current methods for addressing the upgrading of aging equipment rely heavily on a single dimension such as years of operation for assessing the aging risks of the devices, making it difficult to form an accurate risk list by comprehensively considering factors such as historical defects and supply chain conditions. In the dual-configuration transformation, there is a lack of systematic, multi-dimensional, and quantitative selection rules to guide the selection of heterogeneous equipment. Furthermore, from the prototype verification of new protection devices and the simulation comparison of transformation strategies to the continuous status monitoring and dynamic performance verification after commissioning, there is still a lack of a standardized and quantifiable operating procedure that runs through the entire life cycle of the protection system and takes into account both technical feasibility and engineering applicability. Summary of the Invention

[0004] To achieve the above objectives, this application provides the following technical solution: A multi-dimensional collaborative testing and quantitative evaluation method for a hydropower station protection system, characterized in that the method includes: S1: Collect basic information on protection devices and safety automatic devices of lines at specified voltage levels within the hydropower station and establish a structured database. Identify devices that have exceeded their service life and, in conjunction with historical defect records, scheduled maintenance reports, and plug-in replacement history, generate a list of device aging risks that includes risk level assessments. S2: For line protection devices with dual configurations, identify configuration items with the same manufacturer and technical architecture, mark them as high-risk configurations for common cause failures, initiate the heterogeneous replacement selection process, and generate heterogeneous equipment combination suggestions based on a predefined selection rule base; S3: Construct a prototype system of protection device based on industrialized core hardware components, deploy the redeveloped core protection control software on the prototype system, inject a preset fault waveform sequence into the prototype system through a digital simulation test environment, test and record its action judgment results and action response time under simulated fault conditions in and out of the simulated area. S4: Deploy an embedded data acquisition unit in the target protection system to continuously collect multiple key status signals of the protection device and transmit them to the online monitoring server of the station control layer. Analyze the received status signals according to preset evaluation rules and thresholds, calculate and output the corresponding protection device's operational health score, and generate status warning information. S5: Obtain the physical layout information and old system wiring information of the target renovation site, simulate the implementation process of the whole screen replacement plan and the original screen renovation plan, compare the evaluation results of the impact of the two plans on the existing system, select the whole screen replacement as the implementation strategy, and design the terminal block layout for the new protection cabinet according to the old system wiring information to form a pre-installed cabinet. S6: During the planned power outage operation window, the old protection cabinet is de-energized, cables are disconnected and physically dismantled, and the pre-installed cabinet is installed in the designated location. Tests and verifications are performed sequentially to verify the new protection system. Event records, operating status and alarm signals of the newly commissioned protection device are connected to the power station's unified monitoring information platform. S7: Organize dynamic performance verification tests according to multiple predetermined fixed time nodes, and update and optimize the device reliability assessment file based on the results of each verification test.

[0005] Furthermore, S1 also includes: The device's identification information includes at least the device model, manufacturer, software version number, and hardware version number; The operation and maintenance history information includes at least the conclusions of each periodic inspection report, the descriptions and handling processes of recorded defect events, and the replacement time and model of all plug-in level modules; The supply chain status information is obtained by querying the manufacturer to determine the current production and supply status of key components inside the device.

[0006] Furthermore, S3 specifically includes: S31: Select the core computing unit, program storage unit, and running memory unit, design and manufacture a dedicated printed circuit board, and integrate it with power management circuit and clock circuit to form a core processing board. Develop supporting analog input conditioning boards, digital input / output boards, and fiber optic communication interface boards with electrical isolation characteristics. The boards interact with each other via a high-speed backplane bus. S32: Based on the instruction set and hardware resources of the core processing board, develop a low-level board support package software to realize hardware driver, task scheduling and memory management. On the board support package, develop a protection application software framework to provide general basic services. Within the application software framework, adopt a modular design method to develop a differential protection function module and a distance protection function module. S33: Build a real-time digital simulation test environment that includes a primary model of the power system, a transformer model, and a circuit breaker model. Connect the prototype system to the power amplifier and input / output interface of the simulation test environment through its analog input board and digital output board. S34 sets up typical fault scenarios within the simulation environment, including single-phase grounding faults and two-phase short-circuit faults, as well as fault scenarios outside the simulation environment, including bus faults and reverse faults, and generates corresponding current and voltage waveform data streams. S35, the waveform data stream is applied to the analog input channel of the prototype system through a power amplifier, and the protection start signal, protection action output signal and their corresponding time stamp of the prototype system under each fault scenario are monitored and recorded, and the correctness of its action logic and time performance indicators are analyzed.

[0007] Furthermore, S4 specifically includes: S41: Define the set of key status signals inside the protection device to be collected, deploy the embedded data acquisition unit in the protection device chassis, and read the data in the set of key status signals from each functional board in the device through the internal integrated circuit bus, serial peripheral interface bus or parallel digital input port in a periodic polling or interrupt response manner. S42: The embedded data acquisition unit mentioned above uses the industrial Ethernet within the station and adopts a standard protocol to periodically and actively upload the acquired and packaged status signal data to the online monitoring server located in the power station control layer. After receiving the data, the online monitoring server performs structured parsing according to the device identifier, signal type and timestamp, and stores it in the time-series database to form a long-term operating status history record. S43: The online monitoring server loads a preset health assessment rule library. For the monitored protection device, the online monitoring server extracts all status signal data within the most recent assessment period from the time series database, compares the signal values ​​with preset thresholds item by item, and obtains a comprehensive health score value by weighted calculation based on the range of the signal and its weight coefficient. S44: The server periodically calculates the health score and plots its trend curve over time. When the score value is lower than the set attention threshold or the trend curve shows that it continues to decline significantly over a certain period of time, the server automatically generates and issues a corresponding status warning notification.

[0008] Furthermore, in step S2, the construction of the selection rule base specifically includes: Regarding the dimension of operation and maintenance familiarity, a survey was conducted on the familiarity of the existing operation and maintenance personnel of the power plant with the operating interfaces, debugging software and fault codes of different manufacturers' equipment, and the results were quantified and scored. Regarding spare parts commonality, we analyze the differences in physical dimensions and electrical interfaces of commonly used spare parts such as power supply plugs, export plugs, and communication plugs from different manufacturers, and assess the ease of spare parts interchangeability and the potential for inventory optimization. Regarding physical interface compatibility, a detailed comparison was made between the different candidate devices and the existing cabinet design and station system in terms of external terminal block definition, fiber optic interface type, and time synchronization interface protocol. Regarding historical operational stability, we retrieved historical records of the power plant and publicly available industry operation reports to statistically analyze the mean time between failures (MTBF) and typical defect types of similar equipment from different manufacturers.

[0009] Furthermore, in step S5, the implementation process of the simulated full-screen replacement scheme and the original screen modification scheme is as follows: Using 3D design software, digital construction models for both complete screen replacement and original screen renovation were constructed based on the actual on-site cabinet layout diagram and cable list. In the whole screen replacement model, the transportation path and placement process of the new screen cabinet are simulated, and the connection length of all existing cables on the new terminal block is checked to ensure that they are sufficient. In the original screen renovation model, the disassembly of the old device, the installation of the new device, and the reconnection of the secondary lines inside the screen are simulated to evaluate the impact of the internal space layout on equipment heat dissipation and maintenance operations. The model simulation outputs the estimated man-hours, the list of additional materials required, and the potential risks to adjacent operating equipment for both scenarios.

[0010] Furthermore, in step S5, the process of customizing the terminal block layout for the new protection cabinet based on the old system wiring information includes: Obtain the complete terminal block wiring diagram of the old protection cabinet, and identify the number, specifications, peer device, and specific location of each external access cable on the old terminal block; Based on the definition of the external interface of the newly selected protection device, the functional allocation of each layer of terminals on the new terminal block is re-planned to ensure that the functions of all external cables can be correctly transferred to the corresponding input and output ports of the new device, while adhering to the wiring principle of separating strong and weak current terminals and AC and DC terminals. For circuits whose interfaces change due to device replacement, add transition terminals or configure dedicated adapter cables in the design to generate new cabinet manufacturing drawings that include detailed terminal wiring tables and internal wiring diagrams.

[0011] Furthermore, in S6, the sequential execution of test verification specifically includes: For the switch mechanism transmission test, the protection action output is manually triggered on the protection device or simulated by a tester to verify whether the corresponding circuit breaker trip coil and closing coil can be correctly energized, and whether the status change of the circuit breaker auxiliary contacts can be correctly returned to the device input. At the same time, the effectiveness of the anti-pumping relay, pressure interlocking and other functions in the operation circuit is checked. Protection channel swapping test: For protection that relies on communication channels, cooperate with the opposite station to simulate sending and receiving test messages on the local protection device to verify the channel's transmission and reception functions, transmission delay, and clock synchronization accuracy, and ensure that all channel indicators meet the requirements of the protection logic criteria. Load phasor correctness verification involves recording the amplitude and phase angle of each phase current and voltage sampled by the protection device under system load conditions. Simultaneously, the actual values ​​of the primary circuit are measured using tools such as clamp-on phase meters. The sampled values ​​of the device are compared with the actual measured values ​​to calculate the amplitude error and phase error. The correctness of the polarity and wiring of the secondary circuits of the current transformer and voltage transformer is verified to ensure the accuracy of the reference of the protection sampling system.

[0012] Furthermore, in S7, the plurality of fixed time nodes include at least one month, three months, and six months after the system is put into operation; The application of specific forms of interference signals includes: A fast transient pulse group signal with a specified amplitude and frequency is superimposed on the power supply of the protection device, and a power frequency magnetic field interference of a specified intensity is applied near its analog input circuit to test whether its electromagnetic compatibility performance meets the requirements of the operating environment.

[0013] Furthermore, in S7, the dynamic performance verification test performed by the organization specifically refers to: In the power plant station control layer test environment, a typical complex fault case is constructed, which requires the cooperation of multiple devices such as line protection, bus protection, and safety automatic devices to complete the complete fault handling. The analog data and switch events of the fault case are injected into the relevant devices simultaneously or in a specific time sequence through the test tool. The action output sequence, action time difference, and mutual blocking or starting signal interaction behavior of each relevant protection device are observed and recorded to determine whether the coordination logic of the entire protection system meets the requirements of setting calculation and system design. This invention relates to a multi-dimensional collaborative testing and quantitative evaluation method for hydropower station protection systems, belonging to the field of power automation technology. It involves collecting information from protection devices and establishing a database to generate a list of device aging risks; identifying common-cause fault risks in dual-configuration systems and initiating heterogeneous replacement selection; constructing a prototype system based on domestically produced hardware and conducting digital simulation testing; deploying online monitoring units to calculate device operational health scores and issue early warnings; comparing and selecting modification schemes through three-dimensional simulation, customizing the design, and prefabricating new cabinets; performing replacement and commissioning during planned power outages and connecting to a unified monitoring platform; and conducting planned dynamic performance verification tests after commissioning and continuously updating reliability assessment files. This invention achieves closed-loop management throughout the entire lifecycle, from condition assessment, heterogeneous design, prototype verification, online monitoring, refined construction to long-term performance tracking, improving the reliability, safety, and operation and maintenance efficiency of hydropower station protection systems. Attached Figure Description

[0014] Figure 1 A flowchart illustrating the workflow of a multi-dimensional collaborative testing and quantitative evaluation method for a hydropower station protection system, as claimed in an embodiment of the present invention. Figure 2 The second flowchart is a method for multi-dimensional collaborative testing and quantitative evaluation of a hydropower station protection system as claimed in an embodiment of the present invention. Figure 3 The third flowchart is a method for multi-dimensional collaborative testing and quantitative evaluation of a hydropower station protection system, as claimed in an embodiment of the present invention. Detailed Implementation

[0015] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0016] The terms "first," "second," and "third" in this application are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first," "second," or "third" may explicitly or implicitly include at least one of those features. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified. All directional indications in the embodiments of this application, such as up, down, left, right, front, back, etc., are only used to explain the relative positional relationships and movements between components in a specific orientation as shown in the accompanying drawings. If the specific orientation changes, the directional indications will change accordingly. Furthermore, the terms "including" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products, or devices.

[0017] References to embodiments herein mean that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a mutually exclusive, independent, or alternative embodiment. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0018] According to a first embodiment of the present invention, the present invention claims protection for a multi-dimensional collaborative testing and quantitative evaluation method for a hydropower station protection system, referring to... Figure 1 The method includes: S1: Collect basic information on protection devices and safety automatic devices of lines at specified voltage levels within the hydropower station and establish a structured database. Identify devices that have exceeded their service life and, in conjunction with historical defect records, scheduled maintenance reports, and plug-in replacement history, generate a list of device aging risks that includes risk level assessments. S2: For line protection devices with dual configurations, identify configuration items with the same manufacturer and technical architecture, mark them as high-risk configurations for common cause failures, initiate the heterogeneous replacement selection process, and generate heterogeneous equipment combination suggestions based on a predefined selection rule base; S3: Construct a prototype system of protection device based on industrialized core hardware components, deploy the redeveloped core protection control software on the prototype system, inject a preset fault waveform sequence into the prototype system through a digital simulation test environment, test and record its action judgment results and action response time under simulated fault conditions in and out of the simulated area. S4: Deploy an embedded data acquisition unit in the target protection system to continuously collect multiple key status signals of the protection device and transmit them to the online monitoring server of the station control layer. Analyze the received status signals according to preset evaluation rules and thresholds, calculate and output the corresponding protection device's operational health score, and generate status warning information. S5: Obtain the physical layout information and old system wiring information of the target renovation site, simulate the implementation process of the whole screen replacement plan and the original screen renovation plan, compare the evaluation results of the impact of the two plans on the existing system, select the whole screen replacement as the implementation strategy, and design the terminal block layout for the new protection cabinet according to the old system wiring information to form a pre-installed cabinet. S6: During the planned power outage operation window, the old protection cabinet is de-energized, cables are disconnected and physically dismantled, and the pre-installed cabinet is installed in the designated location. Tests and verifications are performed sequentially to verify the new protection system. Event records, operating status and alarm signals of the newly commissioned protection device are connected to the power station's unified monitoring information platform. S7: Organize dynamic performance verification tests according to multiple predetermined fixed time nodes, and update and optimize the device reliability assessment file based on the results of each verification test.

[0019] Furthermore, S1 also includes: The device's identification information includes at least the device model, manufacturer, software version number, and hardware version number; The operation and maintenance history information includes at least the conclusions of each periodic inspection report, the descriptions and handling processes of recorded defect events, and the replacement time and model of all plug-in level modules; The supply chain status information is obtained by querying the manufacturer to determine the current production and supply status of key components inside the device.

[0020] In this embodiment, the implementation process of the method is described in detail, taking the comprehensive renovation and evaluation project of the protection system of the 500kV Longquan Station of the Qingshuihe cascade hydropower station under a large hydropower group as the background.

[0021] After the project commenced, the technical team first conducted a comprehensive survey of all 500kV line protection and safety devices within the Longquan substation. The team developed a dedicated information collection template, dispatched technicians to the site to verify each panel, and collected nameplate information, software versions, and hardware version markings from inspection boards. They also reviewed all technical files of the substation since its commissioning, including annual maintenance reports, defect logs, work orders, and material requisition forms, thereby compiling a detailed description and handling of each device's commissioning date, inspection results, any abnormal events such as component damage or communication interruptions, and all replaced component models and replacement dates. Simultaneously, the project team formally contacted the original equipment manufacturers to inquire about the production and supply status of core CPUs, memory chips, and dedicated logic chips used in the currently operating devices, obtaining official feedback on the supply chain status.

[0022] All of the above information was entered into a specially constructed project management database. Each record corresponds to one device, and the fields cover three main categories: identification, operation and maintenance history, and supply chain status. Subsequently, the analysis program filtered the devices based on the years of operation field, automatically classifying all devices that had exceeded the industry-recommended service life as overdue service objects.

[0023] Furthermore, considering multiple dimensions such as historical defect frequency, the results of the most recent scheduled inspection, and the discontinuation status of core components reported by the manufacturer, an expert panel conducts manual review and rating. For example, a device with a long operating history but few historical defects and whose core components are still reliable might be rated as medium risk; while another device that simultaneously meets the criteria of being past its service life, experiencing frequent defects in recent years, and having its key chips discontinued is marked as high risk. Ultimately, a detailed "Device Aging Risk List" is generated, clarifying the priority of urgent modifications and providing precise targets for subsequent work.

[0024] Furthermore, referring to Figure 2 S3 specifically includes: S31: Select the core computing unit, program storage unit, and running memory unit, design and manufacture a dedicated printed circuit board, and integrate it with power management circuit and clock circuit to form a core processing board. Develop supporting analog input conditioning boards, digital input / output boards, and fiber optic communication interface boards with electrical isolation characteristics. The boards interact with each other via a high-speed backplane bus. S32: Based on the instruction set and hardware resources of the core processing board, develop a low-level board support package software to realize hardware driver, task scheduling and memory management. On the board support package, develop a protection application software framework to provide general basic services. Within the application software framework, adopt a modular design method to develop a differential protection function module and a distance protection function module. S33: Build a real-time digital simulation test environment that includes a primary model of the power system, a transformer model, and a circuit breaker model. Connect the prototype system to the power amplifier and input / output interface of the simulation test environment through its analog input board and digital output board. S34 sets up typical fault scenarios within the simulation environment, including single-phase grounding faults and two-phase short-circuit faults, as well as fault scenarios outside the simulation environment, including bus faults and reverse faults, and generates corresponding current and voltage waveform data streams. S35, the waveform data stream is applied to the analog input channel of the prototype system through a power amplifier, and the protection start signal, protection action output signal and their corresponding time stamp of the prototype system under each fault scenario are monitored and recorded, and the correctness of its action logic and time performance indicators are analyzed.

[0025] In this embodiment, to verify the feasibility of the technical approach, the project team conducted parallel research and development of a new protection device prototype based on an independently controllable hardware platform. On the hardware side, a domestically produced high-performance multi-core processor was selected as the core, paired with domestically produced flash memory and memory chips, and a core processing board was independently designed. Around this core board, a high-precision ADC chip-based analog signal acquisition board, an integrated opto-isolation module on a digital input / output board, and a fiber optic communication board were developed. All boards are interconnected through a self-defined standardized high-speed bus backplane, forming a complete hardware prototype of the device.

[0026] At the software level, the team rewrote the underlying drivers, real-time operating system adaptation layer, and hardware abstraction layer specifically for the processor architecture. Based on this, a modular protection software framework was built, with a focus on developing two core algorithm modules: differential protection and distance protection. The differential protection module implements a sampled-value differential algorithm based on the cycle-Fourier transform, possessing robust logic for inrush current identification and current transformer saturation detection. The distance protection module implements distance measurement and direction determination based on a differential equation solving algorithm and polygon impedance characteristics.

[0027] To verify the correctness of the protection logic of the prototype system, the project team integrated it into a real-time digital simulation system. The simulation system established a detailed primary model including the Longquan substation and its outgoing lines, as well as the opposite system. During testing, various in-zone faults were set up, including single-phase grounding and two-phase short circuits at the end of the line with different transition resistances, as well as out-of-zone faults such as bus faults and reverse outlet faults. The simulation system generated high-precision current and voltage waveforms, which were output to the analog input terminals of the prototype device via a power amplifier. Test personnel closely monitored the behavior of the prototype device under each fault condition: whether the device correctly issued a trip signal within the expected time window during in-zone faults; and whether the device reliably did not operate during out-of-zone faults. The actions and timings of all test cases were recorded and compared with theoretical expectations. The results showed that the protection logic function of the prototype system was complete, and its operational performance met the design requirements, verifying the feasibility of the independent and controllable technology path.

[0028] Furthermore, referring to Figure 3 S4 specifically includes: S41: Define the set of key status signals inside the protection device to be collected, deploy the embedded data acquisition unit in the protection device chassis, and read the data in the set of key status signals from each functional board in the device through the internal integrated circuit bus, serial peripheral interface bus or parallel digital input port in a periodic polling or interrupt response manner. S42: The embedded data acquisition unit mentioned above uses the industrial Ethernet within the station and adopts a standard protocol to periodically and actively upload the acquired and packaged status signal data to the online monitoring server located in the power station control layer. After receiving the data, the online monitoring server performs structured parsing according to the device identifier, signal type and timestamp, and stores it in the time-series database to form a long-term operating status history record. S43: The online monitoring server loads a preset health assessment rule library. For the monitored protection device, the online monitoring server extracts all status signal data within the most recent assessment period from the time series database, compares the signal values ​​with preset thresholds item by item, and obtains a comprehensive health score value by weighted calculation based on the range of the signal and its weight coefficient. S44: The server periodically calculates the health score and plots its trend curve over time. When the score value is lower than the set attention threshold or the trend curve shows that it continues to decline significantly over a certain period of time, the server automatically generates and issues a corresponding status warning notification.

[0029] In this embodiment, after determining the modification plan, the project team designed online monitoring functionality as a standard feature of the new system. First, a set of key status signals to be monitored was defined, specifically including: the output voltage of each DC / DC power supply within the device; the case temperature of the CPU and main chips; the synchronization status of the IRIG-B or PPS time synchronization signals received by the device; the real-time level and change timestamps of all input quantities; the action records of all output relays; the traffic and packet error rate of the Ethernet ports communicating with the station control layer and the opposite protection layer; and the CPU occupancy statistics in different task cycles.

[0030] To facilitate signal acquisition, an embedded data acquisition unit is pre-installed within the new protection device. This unit periodically reads the aforementioned status data from nodes such as the main CPU, power management chip, and communication management chip via an internal bus, such as SPI. The acquisition unit then transmits the packaged status data to the newly deployed online monitoring server for the protection equipment within the station at fixed intervals via the device's own Ethernet port, using a standard protocol.

[0031] After receiving data, the monitoring server stores it in a time-series database. Its core is a built-in health assessment engine, which loads assessment rules and threshold libraries jointly defined by the manufacturer and operations and maintenance experts. For example, the rules stipulate that points are deducted for: power supply voltage deviating from the rated value by more than a certain percentage; CPU temperature consistently exceeding a certain threshold; communication packet error rate exceeding a threshold for multiple consecutive periods; and frequent input jitter. The deduction weight for different signals varies according to their impact on the safe operation of the device. The server calculates the comprehensive health score for each device every minute. Simultaneously, the server tracks score trends. If a device's score drops by more than a certain amount within a day, or if the score remains below a set warning line, the system automatically generates different levels of alerts (attention, warning, and severe), pushing them to the monitoring workstation of operations and maintenance personnel, thus realizing the transformation from routine maintenance to status-based early warning.

[0032] Furthermore, in step S2, the construction of the selection rule base specifically includes: Regarding the dimension of operation and maintenance familiarity, a survey was conducted on the familiarity of the existing operation and maintenance personnel of the power plant with the operating interfaces, debugging software and fault codes of different manufacturers' equipment, and the results were quantified and scored. Regarding spare parts commonality, we analyze the differences in physical dimensions and electrical interfaces of commonly used spare parts such as power supply plugs, export plugs, and communication plugs from different manufacturers, and assess the ease of spare parts interchangeability and the potential for inventory optimization. Regarding physical interface compatibility, a detailed comparison was made between the different candidate devices and the existing cabinet design and station system in terms of external terminal block definition, fiber optic interface type, and time synchronization interface protocol. Regarding historical operational stability, we retrieved historical records of the power plant and publicly available industry operation reports to statistically analyze the mean time between failures (MTBF) and typical defect types of similar equipment from different manufacturers.

[0033] In this embodiment, considering that all 500kV lines at Longquan Substation have dual configurations, the project team focused on analyzing the heterogeneity of these dual configurations. Database queries revealed that both main protection devices on the Longquan-Qingshan line were from the same manufacturer and were the same model, completely violating the anti-accident measure principle that dual configurations should use equipment from different manufacturers. This configuration was flagged by the system and confirmed as a high-risk configuration for common-cause faults. The project team then initiated a heterogeneous replacement selection process for this line.

[0034] The selection process is not a simple replacement, but a comprehensive decision based on a pre-built multi-dimensional selection rule base. First, regarding operational familiarity, a survey is conducted among the station's maintenance teams to assess their understanding of the operating procedures, debugging software, and fault codes of different potential candidate manufacturers' equipment, and a score is given. Second, regarding spare parts versatility, the composition of the existing spare parts library is analyzed, considering the compatibility of the new selected equipment with commonly used and easily damaged components such as power modules and output relays, to reduce future spare parts inventory costs and operational complexity. Third, regarding physical interface compatibility, a detailed comparison is made between the candidate equipment and existing cabinets in terms of design matching, including terminal block size, fiber optic interface type, and time synchronization signal interface protocol, to ensure minimal wiring modifications during upgrades. Finally, regarding historical operational stability, operational analysis reports of the same brand and series of equipment from other power plants within the group are retrieved to examine their mean time between failures (MTBF) and typical defect modes. After comprehensive consideration, the project team proposed a heterogeneous combination solution for the Longquan-Qingshan line, which involves replacing one set of equipment with equipment from another mainstream manufacturer. This solution meets the requirements of the countermeasures while maximizing the convenience of operation and maintenance and the feasibility of the upgrade.

[0035] Furthermore, in step S5, the implementation process of the simulated full-screen replacement scheme and the original screen modification scheme is as follows: Using 3D design software, digital construction models for both complete screen replacement and original screen renovation were constructed based on the actual on-site cabinet layout diagram and cable list. In the whole screen replacement model, the transportation path and placement process of the new screen cabinet are simulated, and the connection length of all existing cables on the new terminal block is checked to ensure that they are sufficient. In the original screen renovation model, the disassembly of the old device, the installation of the new device, and the reconnection of the secondary lines inside the screen are simulated to evaluate the impact of the internal space layout on equipment heat dissipation and maintenance operations. The model simulation outputs the estimated man-hours, the list of additional materials required, and the potential risks to adjacent operating equipment for both scenarios.

[0036] In this embodiment, given the limited space for the 500kV protection room at Longquan Substation and the dense concentration of operating equipment, the project team conducted an in-depth digital simulation comparison of two options: replacing the entire protection panel and modifying the existing panel. Using 3D design software, construction models for both options were established based on precise on-site dimensions and the cable inventory.

[0037] In the complete screen replacement model, the transportation path of the new screen cabinet from the warehouse through the handling channel to the protection room was simulated, and the clearance height and load-bearing capacity of the path were confirmed. The process of removing the old screen and placing the new screen was simulated, and the length of each original cable from the old terminal block to the predetermined installation position of the new screen cabinet was verified. The model confirmed that all cable lengths were sufficient and no re-laying was required.

[0038] In the original screen renovation model, the workspace for disassembling and assembling internal devices and wiring was simulated when the adjacent screen cabinets were running without power interruption, and the construction safety risks were assessed. The layout of new devices and new terminal blocks was simulated in the original screen cabinet frame. It was found that due to the difference in depth and interface position between the old and new devices, some internal wiring will be very cramped, which may affect heat dissipation and maintenance.

[0039] After comprehensive comparison, although the overall screen replacement solution was slightly more expensive in terms of initial procurement and transportation costs, it had significant advantages such as a clear construction window, complete removal of the old screen, complete installation of the new screen, high-quality factory-installed wiring inside the cabinet, complete elimination of the aging risks inherent in the old cabinet, and more controllable on-site construction risks. Therefore, the project team decided to adopt the overall screen replacement solution.

[0040] Based on the decision, the design team customized the design for each panel of the cabinet that needed replacement. They carefully analyzed the terminal block wiring diagram of the old cabinet, clarifying the origin and destination of each cable. According to the external interface definition of the newly selected protection device, they redesigned the terminal block layout of the new cabinet, ensuring that every existing cable could find a corresponding, functionally correct new terminal for connection. For the few circuits added or removed due to the optimization of the protection principle, these were clearly indicated in the design drawings, and necessary transfer schemes were planned. The final manufacturing drawings and terminal wiring tables enabled the cabinet manufacturer to complete the assembly, binding, and testing of all internal secondary wiring in the factory.

[0041] Furthermore, in step S5, the process of customizing the terminal block layout for the new protection cabinet based on the old system wiring information includes: Obtain the complete terminal block wiring diagram of the old protection cabinet, and identify the number, specifications, peer device, and specific location of each external access cable on the old terminal block; Based on the definition of the external interface of the newly selected protection device, the functional allocation of each layer of terminals on the new terminal block is re-planned to ensure that the functions of all external cables can be correctly transferred to the corresponding input and output ports of the new device, while adhering to the wiring principle of separating strong and weak current terminals and AC and DC terminals. For circuits whose interfaces change due to device replacement, add transition terminals or configure dedicated adapter cables in the design to generate new cabinet manufacturing drawings that include detailed terminal wiring tables and internal wiring diagrams.

[0042] Furthermore, in S6, the sequential execution of test verification specifically includes: For the switch mechanism transmission test, the protection action output is manually triggered on the protection device or simulated by a tester to verify whether the corresponding circuit breaker trip coil and closing coil can be correctly energized, and whether the status change of the circuit breaker auxiliary contacts can be correctly returned to the device input. At the same time, the effectiveness of the anti-pumping relay, pressure interlocking and other functions in the operation circuit is checked. Protection channel swapping test: For protection that relies on communication channels, cooperate with the opposite station to simulate sending and receiving test messages on the local protection device to verify the channel's transmission and reception functions, transmission delay, and clock synchronization accuracy, and ensure that all channel indicators meet the requirements of the protection logic criteria. Load phasor correctness verification involves recording the amplitude and phase angle of each phase current and voltage sampled by the protection device under system load conditions. Simultaneously, the actual values ​​of the primary circuit are measured using tools such as clamp-on phase meters. The sampled values ​​of the device are compared with the actual measured values ​​to calculate the amplitude error and phase error. The correctness of the polarity and wiring of the secondary circuits of the current transformer and voltage transformer is verified to ensure the accuracy of the reference of the protection sampling system.

[0043] In this embodiment, the renovation work was carried out during the planned power outage window. The construction team first safely isolated the old power distribution cabinet, marked all cables, and then dismantled it. Next, the pre-installed new power distribution cabinet, with all wiring, device installation, and preliminary functional testing completed at the factory, was moved to its location and secured. Then, technical personnel, according to the design drawings, accurately connected each of the marked existing cables to the new terminal blocks.

[0044] After the cable was restored, the crucial on-site commissioning phase began: Switchgear test: A fault is simulated on the protection device using a tester to trigger the protection trip output. On-site verification shows that the corresponding 500kV circuit breaker correctly trips, and its auxiliary contact status changes correctly return to the device; the closing circuit is also tested. This process verifies the integrity of the entire circuit from the protection logic output to the circuit breaker's first operation, including the operating box, pressure plate, cables, and circuit breaker body mechanism.

[0045] Channel integration test: This test is conducted in coordination with the power station on the opposite side of the line for longitudinal protection. Various test signals are simulated and transmitted on the local device, and the opposite side confirms correct reception and responds. Simultaneously, the self-loop and cross-loop functions of the channel are tested, and the channel transmission delay is measured. This test ensures that the protection devices on both sides can reliably exchange information through the communication channel, forming a complete, high-speed protection system for the entire line.

[0046] Phasor verification under load: This is performed after the line is energized and the load current is stable. Simultaneously, the three-phase current and voltage amplitudes and phases sampled in real time by the protection device are read, and the actual secondary values ​​at the same moment are measured using a high-precision clamp-on phase meter at the terminal block. The two sets of data are compared, and the amplitude difference and phase difference are calculated to verify the absolute correctness of the polarity, phase sequence, and wiring of the current and voltage transformer secondary circuits. This is the cornerstone of the correct operation of the protection device.

[0047] After all commissioning is completed and qualified, the communication interface of the newly commissioned protection device will be connected to the power plant monitoring system to realize telemetry, communication and remote control functions, and ensure that its event records and fault waveforms can be uploaded to the fault information management substation normally.

[0048] Furthermore, in S7, the plurality of fixed time nodes include at least one month, three months, and six months after the system is put into operation; The application of specific forms of interference signals includes: A fast transient pulse group signal with a specified amplitude and frequency is superimposed on the power supply of the protection device, and a power frequency magnetic field interference of a specified intensity is applied near its analog input circuit to test whether its electromagnetic compatibility performance meets the requirements of the operating environment.

[0049] Furthermore, in S7, the dynamic performance verification test performed by the organization specifically refers to: In the power plant station control layer test environment, a typical complex fault case is constructed, which requires the cooperation of multiple devices such as line protection, bus protection, and safety automatic devices to complete the complete fault handling. The analog data and switch events of the fault case are injected into the relevant devices simultaneously or in a specific time sequence through the test tool. The action output sequence, action time difference, and mutual blocking or starting signal interaction behavior of each relevant protection device are observed and recorded to determine whether the coordination logic of the entire protection system meets the requirements of setting calculation and system design.

[0050] In this embodiment, the commissioning of the new system is not the end of the project. The project team has developed a detailed post-commissioning follow-up testing plan.

[0051] One month after commissioning, the first review was conducted. The focus was on interference immunity testing: using specialized testing equipment, standard-specified electrical fast transient / burst interference was applied to the power port of the protection cabinet, while simultaneously monitoring for any malfunctions or abnormalities in the protection devices; a power frequency magnetic field was applied near the chassis to check if the sampled values ​​were significantly affected. The test results were used to verify the stability of the device in real-world complex electromagnetic environments.

[0052] Three months after commissioning, a second review was conducted, focusing on testing the consistency of coordinated operation of multiple devices. A complex scenario was simulated, involving a line fault accompanied by circuit breaker failure. A coordinated fault quantity was injected into the line protection, busbar protection, and circuit breaker failure protection devices using a testing instrument. The following were observed and recorded: whether the line protection correctly tripped its own circuit breaker first; and whether the failure protection correctly started according to the preset time limit and tripped the adjacent bus tie switch and all relevant busbar feeder switches when the simulated circuit breaker failed to operate. This test verified the correctness of the logical coordination and time gradation between different protection devices within the substation.

[0053] A third review was conducted six months after commissioning. This review focused on verifying the performance stability after long-term operation. Sampling accuracy was checked again, and data was compared with that from the initial commissioning period to observe for any drift. The device's self-diagnostic functions were comprehensively checked, simulating minor internal anomalies such as slight power fluctuations, configuration checksum errors, etc., to verify that the device could accurately report the corresponding warning signals without malfunctioning or losing its protective functions.

[0054] Each verification test result is compiled into a formal report and archived together with the pre-commissioning test data and trend data from the health monitoring system, and updated in the device's full lifecycle reliability file. This series of planned and focused post-commissioning tests constitutes effective supervision and closed-loop management of the long-term reliable operation of the protection system, ensuring the durability of the modification effects.

[0055] In the several embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces, or indirect coupling or communication connection between apparatuses or units, and may be electrical, mechanical, or other forms.

[0056] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated units described above can be implemented in hardware or as software functional units. The above are merely embodiments of this application and do not limit the patent scope of this application. Any equivalent structural or procedural transformations made based on the description and drawings of this application, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.

[0057] The specific embodiments of the invention have been described in detail above, but they are only examples, and this application is not limited to the specific embodiments described above. For those skilled in the art, any equivalent modifications or substitutions to the invention are also within the scope of this application. Therefore, all equivalent changes, modifications, and improvements made without departing from the spirit and principles of this application should be covered within the scope of this application.

Claims

1. A multi-dimensional collaborative testing and quantitative evaluation method for a hydropower station protection system, characterized in that, The method includes: S1: Collect basic information on protection devices and safety automatic devices of lines at specified voltage levels within the hydropower station and establish a structured database. Identify devices that have exceeded their service life and, in conjunction with historical defect records, scheduled maintenance reports, and plug-in replacement history, generate a list of device aging risks that includes risk level assessments. S2: For line protection devices with dual configurations, identify configuration items with the same manufacturer and technical architecture, mark them as high-risk configurations for common cause failures, initiate the heterogeneous replacement selection process, and generate heterogeneous equipment combination suggestions based on a predefined selection rule base; S3: Construct a prototype system of protection device based on industrialized core hardware components, deploy the redeveloped core protection control software on the prototype system, inject a preset fault waveform sequence into the prototype system through a digital simulation test environment, test and record its action judgment results and action response time under simulated fault conditions in and out of the simulated area. S4: Deploy an embedded data acquisition unit in the target protection system to continuously collect multiple key status signals of the protection device and transmit them to the online monitoring server of the station control layer. Analyze the received status signals according to preset evaluation rules and thresholds, calculate and output the corresponding protection device's operational health score, and generate status warning information. S5: Obtain the physical layout information and old system wiring information of the target renovation site, simulate the implementation process of the whole screen replacement plan and the original screen renovation plan, compare the evaluation results of the impact of the two plans on the existing system, select the whole screen replacement as the implementation strategy, and design the terminal block layout for the new protection cabinet according to the old system wiring information to form a pre-installed cabinet. S6: During the planned power outage operation window, the old protection cabinet is de-energized, cables are disconnected and physically dismantled, and the pre-installed cabinet is installed in the designated location. Tests and verifications are performed sequentially to verify the new protection system. Event records, operating status and alarm signals of the newly commissioned protection device are connected to the power station's unified monitoring information platform. S7: Organize dynamic performance verification tests according to multiple predetermined fixed time nodes, and update and optimize the device reliability assessment file based on the results of each verification test.

2. The multi-dimensional collaborative testing and quantitative evaluation method for hydropower station protection systems according to claim 1, characterized in that, S1 also includes: The device's identification information includes at least the device model, manufacturer, software version number, and hardware version number; The operation and maintenance history information includes at least the conclusions of each periodic inspection report, the descriptions and handling processes of recorded defect events, and the replacement time and model of all plug-in level modules; The supply chain status information is obtained by querying the manufacturer to determine the current production and supply status of key components inside the device.

3. The multi-dimensional collaborative testing and quantitative evaluation method for hydropower station protection systems according to claim 1, characterized in that, S3 specifically includes: S31: Select the core computing unit, program storage unit, and running memory unit, design and manufacture a dedicated printed circuit board, and integrate it with power management circuit and clock circuit to form a core processing board. Develop supporting analog input conditioning boards, digital input / output boards, and fiber optic communication interface boards with electrical isolation characteristics. The boards interact with each other via a high-speed backplane bus. S32: Based on the instruction set and hardware resources of the core processing board, develop a low-level board support package software to realize hardware driver, task scheduling and memory management. On the board support package, develop a protection application software framework to provide general basic services. Within the application software framework, adopt a modular design method to develop a differential protection function module and a distance protection function module. S33: Build a real-time digital simulation test environment that includes a primary model of the power system, a transformer model, and a circuit breaker model. Connect the prototype system to the power amplifier and input / output interface of the simulation test environment through its analog input board and digital output board. S34 sets up typical fault scenarios within the simulation environment, including single-phase grounding faults and two-phase short-circuit faults, as well as fault scenarios outside the simulation environment, including bus faults and reverse faults, and generates corresponding current and voltage waveform data streams. S35, the waveform data stream is applied to the analog input channel of the prototype system through a power amplifier, and the protection start signal, protection action output signal and their corresponding time stamp of the prototype system under each fault scenario are monitored and recorded, and the correctness of its action logic and time performance indicators are analyzed.

4. The multi-dimensional collaborative testing and quantitative evaluation method for hydropower station protection systems according to claim 1, characterized in that, S4 specifically includes: S41: Define the set of key status signals inside the protection device to be collected, deploy the embedded data acquisition unit in the protection device chassis, and read the data in the set of key status signals from each functional board in the device through the internal integrated circuit bus, serial peripheral interface bus or parallel digital input port in a periodic polling or interrupt response manner. S42: The embedded data acquisition unit mentioned above uses the industrial Ethernet within the station and adopts a standard protocol to periodically and actively upload the acquired and packaged status signal data to the online monitoring server located in the power station control layer. After receiving the data, the online monitoring server performs structured parsing according to the device identifier, signal type and timestamp, and stores it in the time-series database to form a long-term operating status history record. S43: The online monitoring server loads a preset health assessment rule library. For the monitored protection device, the online monitoring server extracts all status signal data within the most recent assessment period from the time series database, compares the signal values ​​with preset thresholds item by item, and obtains a comprehensive health score value by weighted calculation based on the range of the signal and its weight coefficient. S44: The server periodically calculates the health score and plots its trend curve over time. When the score value is lower than the set attention threshold or the trend curve shows that it continues to decline significantly over a certain period of time, the server automatically generates and issues a corresponding status warning notification.

5. The multi-dimensional collaborative testing and quantitative evaluation method for hydropower station protection systems according to claim 1, characterized in that, In step S2, the construction of the selection rule base specifically includes: Regarding the dimension of operation and maintenance familiarity, a survey was conducted on the familiarity of the existing operation and maintenance personnel of the power plant with the operating interfaces, debugging software and fault codes of different manufacturers' equipment, and the results were quantified and scored. Regarding spare parts commonality, we analyze the differences in physical dimensions and electrical interfaces of commonly used spare parts such as power supply plugs, export plugs, and communication plugs from different manufacturers, and assess the ease of spare parts interchangeability and the potential for inventory optimization. Regarding physical interface compatibility, a detailed comparison was made between the different candidate devices and the existing cabinet design and station system in terms of external terminal block definition, fiber optic interface type, and time synchronization interface protocol. Regarding historical operational stability, we retrieved historical records of the power plant and publicly available industry operation reports to statistically analyze the mean time between failures (MTBF) and typical defect types of similar equipment from different manufacturers.

6. The multi-dimensional collaborative testing and quantitative evaluation method for hydropower station protection systems according to claim 1, characterized in that, In step S5, the implementation process of the simulated full-screen replacement scheme and the original screen modification scheme is as follows: Using 3D design software, digital construction models for both complete screen replacement and original screen renovation were constructed based on the actual on-site cabinet layout diagram and cable list. In the whole screen replacement model, the transportation path and placement process of the new screen cabinet are simulated, and the connection length of all existing cables on the new terminal block is checked to ensure that they are sufficient. In the original screen renovation model, the disassembly of the old device, the installation of the new device, and the reconnection of the secondary lines inside the screen are simulated to evaluate the impact of the internal space layout on equipment heat dissipation and maintenance operations. The model simulation outputs the estimated man-hours, the list of additional materials required, and the potential risks to adjacent operating equipment for both scenarios.

7. The multi-dimensional collaborative testing and quantitative evaluation method for hydropower station protection systems according to claim 1, characterized in that, In step S5, the process of customizing the terminal block layout for the new protection cabinet based on the old system wiring information includes: Obtain the complete terminal block wiring diagram of the old protection cabinet, and identify the number, specifications, peer device, and specific location of each external access cable on the old terminal block; Based on the definition of the external interface of the newly selected protection device, the functional allocation of each layer of terminals on the new terminal block is re-planned to ensure that the functions of all external cables can be correctly transferred to the corresponding input and output ports of the new device, while adhering to the wiring principle of separating strong and weak current terminals and AC and DC terminals. For circuits whose interfaces change due to device replacement, add transition terminals or configure dedicated adapter cables in the design to generate new cabinet manufacturing drawings that include detailed terminal wiring tables and internal wiring diagrams.

8. The multi-dimensional collaborative testing and quantitative evaluation method for hydropower station protection systems according to claim 1, characterized in that, In step S6, the sequential execution of test verification specifically includes: For the switch mechanism transmission test, the protection action output is manually triggered on the protection device or simulated by a tester to verify whether the corresponding circuit breaker trip coil and closing coil can be correctly energized, and whether the status change of the circuit breaker auxiliary contacts can be correctly returned to the device input. At the same time, the effectiveness of the anti-pumping relay, pressure interlocking and other functions in the operation circuit is checked. Protection channel swapping test: For protection that relies on communication channels, cooperate with the opposite station to simulate sending and receiving test messages on the local protection device to verify the channel's transmission and reception functions, transmission delay, and clock synchronization accuracy, and ensure that all channel indicators meet the requirements of the protection logic criteria. Load phasor correctness verification involves recording the amplitude and phase angle of each phase current and voltage sampled by the protection device under system load conditions. Simultaneously, the actual values ​​of the primary circuit are measured using tools such as clamp-on phase meters. The sampled values ​​of the device are compared with the actual measured values ​​to calculate the amplitude error and phase error. The correctness of the polarity and wiring of the secondary circuits of the current transformer and voltage transformer is verified to ensure the accuracy of the reference of the protection sampling system.

9. The multi-dimensional collaborative testing and quantitative evaluation method for hydropower station protection systems according to claim 1, characterized in that, In S7, the plurality of fixed time nodes include at least one month, three months and six months after the system is put into operation; The application of specific forms of interference signals includes: A fast transient pulse group signal with a specified amplitude and frequency is superimposed on the power supply of the protection device, and a power frequency magnetic field interference of a specified intensity is applied near its analog input circuit to test whether its electromagnetic compatibility performance meets the requirements of the operating environment.

10. The multi-dimensional collaborative testing and quantitative evaluation method for hydropower station protection systems according to claim 1, characterized in that, In S7, the dynamic performance verification test of the organization specifically refers to: In the power plant station control layer test environment, a typical complex fault case is constructed, which requires the cooperation of multiple devices such as line protection, bus protection, and safety automatic devices to complete the complete fault handling. The analog data and switch events of the fault case are injected into the relevant devices simultaneously or in a specific time sequence through the test tool. The action output sequence, action time difference, and mutual blocking or starting signal interaction behavior of each relevant protection device are observed and recorded to determine whether the coordination logic of the entire protection system meets the requirements of setting calculation and system design.

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