Predictive maintenance method and system for relay protection equipment

Abstract

The invention relates to the technical field of predictive maintenance, in particular to a predictive maintenance method and system for relay protection equipment, and the method comprises the following steps: calculating the change trend of each operation parameter in each time window based on the operation parameters of the relay equipment, and obtaining the change rate of the operation state of the relay equipment; according to the method, the running trend under different time scales is refined, the running state change rate is accurately extracted to quantify the health state of the relay equipment, and the health score attenuation rate is calculated in combination with the equipment aging degree, the contact abrasion degree and the relay action times, so that the health degree decline rate is measured, and accurate judgment of equipment maintenance requirements can be realized; and the maintenance task priority is calculated in combination with the importance weight of the equipment, so that the maintenance resource configuration is more targeted, the load fluctuation condition of the equipment is quantified, and the maintenance period is dynamically adjusted according to the set threshold value to match the load change trend of the equipment, thereby avoiding the problem of excessive maintenance or insufficient maintenance.

Description

Technical Field

[0001] The present invention relates to the technical field of predictive maintenance, and in particular to a predictive maintenance method and system for relay protection equipment. Background Art

[0002] The field of predictive maintenance technology includes maintenance methods based on equipment operation data analysis, condition monitoring and fault prediction. The core content of this technical field involves the use of sensor acquisition, anomaly detection and trend analysis technology to evaluate the health status of equipment, and predict possible future failures based on historical data and models to optimize maintenance plans. The overall application of predictive maintenance technology includes the acquisition and storage of equipment monitoring data, the establishment of health status assessment models, the application of anomaly detection algorithms, the implementation of life prediction methods, and the automatic optimization of maintenance plans. This field usually combines statistical analysis, machine learning models, fault tree analysis and other methods to reduce unplanned equipment downtime and optimize maintenance resource allocation.

[0003] Among them, the predictive maintenance method of relay protection equipment refers to the monitoring of the health status of relay protection equipment and the formulation of maintenance strategies based on the operating parameters, relay protection action records and fault history data of the relay protection equipment through multi-dimensional feature analysis, state assessment model calculation and trend prediction methods. This method targets key technical matters of relay protection equipment, including operating status monitoring, fault prediction analysis, and maintenance strategy optimization. Operating status monitoring uses parameters such as current, voltage, frequency, and phase angle of relay protection equipment to evaluate the health status of equipment through time series analysis and feature extraction methods. Fault prediction analysis uses historical fault records, relay action data and equipment aging trends to predict short-term and long-term fault trends based on probability statistics methods or model-based diagnostic methods. Maintenance strategy optimization combines equipment health assessment data with maintenance resource configuration constraints, and uses decision optimization models or heuristic algorithms to formulate optimal maintenance scheduling plans.

[0004] Traditional maintenance methods mainly rely on equipment operation data for status monitoring and fault prediction, and do not distinguish between status changes on different time scales, making it difficult to distinguish between short-term fluctuations and long-term degradation of equipment. This will lead to a lack of targeted maintenance strategies, and a weak ability to respond to real-time changes in equipment health. It is easy to ignore the stage-by-stage changes in health status, thereby affecting the accuracy of maintenance timing. Maintenance strategy optimization mainly relies on equipment health assessment data, but does not fully consider the equipment importance weight, load fluctuations, and changing trends in equipment operating status, which will lead to an unbalanced allocation of maintenance resources and make it difficult to optimize maintenance plans based on load fluctuations. As a result, the equipment uses fixed maintenance cycles under high or low load conditions, which cannot adapt to actual working conditions. Summary of the invention

[0005] The purpose of the present invention is to solve the shortcomings existing in the prior art and to propose a predictive maintenance method and system for relay protection equipment.

[0006] In order to achieve the above object, the present invention adopts the following technical solution: a predictive maintenance method for relay protection equipment, comprising the following steps: S1: Based on the operating parameters of the relay equipment, the change trend of each operating parameter in each time window is calculated to obtain the change rate of the operating state of the relay equipment; S2: Based on the change rate of the operating state of the relay device, calculate the health score of the relay device, select the devices whose health score is lower than the health threshold, calculate the decay rate of the health score per unit time, and obtain the health decline rate of the relay device; S3: Based on the health decline rate of the relay device, determine whether the equipment needs to be maintained, and calculate the equipment maintenance task priority in combination with the equipment importance weight parameter to obtain a maintenance task priority list; S4: Based on the maintenance task priority list, obtain the load current, breaking times and current flow time of the relay equipment, calculate the mean and standard deviation of the load change rate, determine the load fluctuation, adjust the maintenance cycle, and obtain the maintenance adjustment amount of the relay equipment; S5: Based on the relay equipment maintenance adjustment amount and the maintenance task priority list, the maintenance personnel demand and spare parts reserve demand of the relay protection relay are calculated, and the maintenance time window is adjusted to obtain the relay equipment maintenance resource allocation information.

[0007] As a further solution of the present invention, the relay device operating state change rate includes the coil current change rate, the contact resistance increment rate, the tripping current threshold fluctuation trend and the protection logic trigger frequency change value; the relay device health degradation rate is specifically the health score decay rate, the coil aging trend value, the contact wear growth amount and the relay action abnormality ratio; the maintenance task priority list includes the maintenance task sorting coefficient, the fault impact level coefficient, the health degradation assessment value and the task execution urgency; the relay device maintenance adjustment amount is specifically the maintenance interval correction value, the load fluctuation impact coefficient, the maintenance plan adjustment time and the equipment maintenance level change information; the relay device maintenance resource allocation information includes the maintenance personnel demand, the spare parts reserve demand, the maintenance time window and the task execution work order number.

[0008] As a further solution of the present invention, the step of obtaining the rate of change of the operating state of the relay device is specifically as follows: S111: Based on the operating parameters of the relay equipment, the coil current, contact resistance, trip current threshold and the number of relay protection logic triggering are obtained, and short-term, medium-term and long-term time windows are set to calculate the data change rate of each operating parameter in each time window, using the formula: ; Calculate the change rate of the operating parameters in each time window to obtain the operating parameter change information; in, Representative The operating parameters at time The rate of change within Representative time The moment operating parameters, Representative time No. operating parameters, Represents time window Length of time; S112: calling the operation parameter change information, calculating the change trend of each parameter in different time windows, and fitting the slope of the trend change by linear regression to obtain the slope of the operation state change; S113: Call the operating state change slope, and according to the mean and variance of each parameter change rate, screen the operating parameters whose change trend exceeds the preset change threshold, and calculate the parameter change rate ratio to obtain the relay equipment operating state change rate.

[0009] As a further solution of the present invention, the steps for obtaining the rate of decline of the health of the relay device are specifically as follows: S211: Based on the rate of change of the operating state of the relay device, the formula is used: ; Calculate the health score and obtain the health information of the relay equipment; in, Represents the health score, Representative The current rate of change of the operating parameters, Representative The influence weight of various operating parameters, Represents the total number of operating parameters; S212: calling the health information of the relay device, setting a health threshold, screening devices whose health scores are lower than the health threshold, obtaining information on the coil aging degree, contact wear degree and relay operation times of the devices, and obtaining a set of devices whose health scores are lower than the threshold; S213: Call the device set whose health is lower than the threshold, calculate the decay rate of the health score per unit time, and obtain the health decline rate of the relay device.

[0010] As a further solution of the present invention, the steps of obtaining the maintenance task priority list are specifically as follows: S311: Based on the health decline rate of the relay device, the health decline rate is compared with the preset attenuation threshold to determine whether the device needs to be maintained, and the devices whose health decline rate is higher than the attenuation threshold are selected to obtain a set of devices that need maintenance; S312: Call the maintenance-required equipment set, and combine the equipment importance weight parameter to adopt the formula: ; Calculate the maintenance task priority for each device; in, Represents the equipment maintenance task priority, Represents the rate of health decline, Represents the importance weight of the device, Represents the change in health score, Represents the time period since the last maintenance of the equipment; S313: calling the maintenance task priority of the equipment, sorting the equipment to be maintained according to the priority, and obtaining a maintenance task priority list.

[0011] As a further solution of the present invention, the step of obtaining the maintenance adjustment amount of the relay device is specifically as follows: S411: Based on the maintenance task priority list, the load current, the number of disconnections and the flow time of the relay device are obtained, and the mean and standard deviation of the load change rate are calculated to obtain a load change rate statistical value; S412: Call the load change rate statistics to determine the load fluctuation situation, and compare it with the preset load fluctuation threshold to determine whether the maintenance cycle needs to be adjusted, using the formula: ; Calculate adjusted maintenance intervals; in, represents the adjusted maintenance cycle, Represents the current maintenance cycle, Represents the standard deviation of the load change rate, Represents the mean value of the load change rate; S413: calling the adjusted maintenance cycle, calculating the required adjustment amount according to the current maintenance cycle, and obtaining the maintenance adjustment amount of the relay equipment.

[0012] As a further solution of the present invention, the steps for obtaining the relay equipment maintenance resource allocation information are specifically as follows: S511: Based on the maintenance adjustment amount of the relay equipment and the maintenance task priority list, calculate the maintenance personnel demand of the relay protection relay, obtain the number of maintenance tasks, the standard working hours of a single task and the available working time resources, and obtain the maintenance personnel demand information; S512: Call the maintenance personnel demand information, combine the spare parts consumption of the equipment maintenance task, and combine the inventory status and the safety reserve threshold, and use the formula: ; Calculate spare parts reserve requirements; in, represents the spare parts reserve demand, Representative Spare parts consumption rate of each type of equipment, Representative The maintenance cycle after the equipment is adjusted. Representative The supply rate of spare parts that can be replenished per unit time for this type of equipment, Represents the current inventory quantity, Represents the total number of devices; S513: The spare parts reserve demand is called, combined with the maintenance personnel demand, the maintenance time window is adjusted, the task allocation is optimized, and the relay equipment maintenance resource allocation information is obtained.

[0013] A relay protection device predictive maintenance system, the relay protection device predictive maintenance system is used to execute the above relay protection device predictive maintenance method, the system comprises: The operation status analysis module calculates the change trend of each operation parameter in each time window based on the operation parameters of the relay equipment, and obtains the change rate of the operation status of the relay equipment; The health change analysis module selects devices whose health scores are lower than the health threshold based on the change rate of the operating state of the relay device, calculates the decay rate of the health score per unit time, and obtains the health decline rate of the relay device; The maintenance task sorting module determines whether the equipment needs to be maintained based on the health decline rate of the relay equipment, calculates the equipment maintenance task priority, and obtains a maintenance task priority list; The maintenance cycle adjustment module calculates the mean and standard deviation of the load change rate based on the maintenance task priority list, determines the load fluctuation, adjusts the maintenance cycle, and obtains the maintenance adjustment amount of the relay equipment; The maintenance resource scheduling module calculates the maintenance personnel demand and spare parts reserve demand of the relay protection relay based on the relay equipment maintenance adjustment amount and the maintenance task priority list, and adjusts the maintenance time window to obtain the relay equipment maintenance resource allocation information.

[0014] Compared with the prior art, the advantages and positive effects of the present invention are: In the present invention, by refining the operation trends under different time scales, the operation state change rate is accurately extracted to quantify the health state of the relay equipment. Through health score calculation and health threshold screening, potential problems can be identified before the equipment has a significant failure, and the health score decay rate is calculated in combination with the equipment aging degree, contact wear and relay operation times, so as to measure the health decline rate, making the assessment of equipment state degradation more precise. The health decline rate is compared with the preset decay threshold, which can realize the accurate judgment of equipment maintenance needs, and the maintenance task priority is calculated in combination with the equipment importance weight, so that the maintenance resource allocation is more targeted. The load current, the number of disconnections and the flow time are introduced to calculate the load change rate mean and standard deviation, which can quantify the equipment load fluctuation, and dynamically adjust the maintenance cycle according to the set threshold to match the equipment load change trend. The maintenance personnel demand and spare parts reserve demand are calculated by the maintenance adjustment amount and the maintenance task priority, and the maintenance resource allocation is optimized in combination with the inventory status, so that the maintenance strategy can be dynamically optimized with the equipment operation status, improve resource utilization efficiency, and avoid excessive maintenance or insufficient maintenance. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the method flow of the present invention; Figure 2 A flow chart for obtaining the rate of change of the operating state of a relay device for the present invention; Figure 3 A flow chart for obtaining a rate of decline in health of a relay device for the present invention; Figure 4 A flowchart for obtaining a maintenance task priority list for the present invention; Figure 5 A flow chart for obtaining the maintenance adjustment amount of relay equipment for the present invention; Figure 6 A flow chart of obtaining relay equipment maintenance resource allocation information for the present invention. DETAILED DESCRIPTION

[0016] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0017] In the description of the present invention, it should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, in the description of the present invention, "multiple" means two or more, unless otherwise clearly and specifically defined.

[0018] Embodiment 1 See also Figure 1 The present invention provides a technical solution: a predictive maintenance method for relay protection equipment, comprising the following steps: S1: Based on the operating parameters of the relay equipment, including coil current, contact resistance, trip current threshold and the number of relay protection logic triggering, set short-term, medium-term and long-term time windows, calculate the change trend of each operating parameter in each time window, and obtain the change rate of the operating state of the relay equipment; S2: Based on the rate of change of the operating status of the relay equipment, the health score of the relay equipment is calculated, the health threshold is set, and the equipment with a health score lower than the health threshold is screened. The data of the coil aging degree, contact wear degree and relay operation times of the equipment are called, and the health score attenuation rate per unit time is calculated to obtain the health decline rate of the relay equipment; S3: Based on the health decline rate of the relay equipment, it is compared with the preset attenuation threshold to determine whether the equipment needs to be maintained. Combined with the equipment importance weight parameter, the equipment maintenance task priority is calculated, the maintenance tasks are sorted, and a maintenance task priority list is obtained; S4: Based on the maintenance task priority list, obtain the load current, breaking times and current-carrying time of the relay equipment, calculate the mean and standard deviation of the load change rate, judge the load fluctuation, adjust the maintenance cycle according to the set load fluctuation threshold, and obtain the maintenance adjustment amount of the relay equipment; S5: Based on the relay equipment maintenance adjustment amount and the maintenance task priority list, the maintenance personnel demand and spare parts reserve demand of the relay protection relay are calculated, and the maintenance time window is adjusted to obtain the relay equipment maintenance resource allocation information.

[0019] The rate of change of the operating status of the relay equipment includes the coil current change rate, the contact resistance increment rate, the tripping current threshold fluctuation trend and the protection logic trigger frequency change value. The relay equipment health degradation rate includes the health score attenuation rate, the coil aging trend value, the contact wear growth amount and the relay action abnormality ratio. The maintenance task priority list includes the maintenance task sorting coefficient, the fault impact level coefficient, the health degradation assessment value and the task execution urgency. The relay equipment maintenance adjustment amount includes the maintenance interval correction value, the load fluctuation impact coefficient, the maintenance plan adjustment time and the equipment maintenance level change information. The relay equipment maintenance resource allocation information includes the maintenance personnel demand, the spare parts reserve demand, the maintenance time window and the task execution work order number.

[0020] See also Figure 2 , the specific steps for obtaining the rate of change of the operating state of the relay device are: S111: Based on the operating parameters of the relay equipment, the coil current, contact resistance, trip current threshold and the number of relay protection logic triggering are obtained, and short-term, medium-term and long-term time windows are set to calculate the data change rate of each operating parameter in each time window, using the formula: ; Calculate the change rate of the operating parameters in each time window to obtain the operating parameter change information; in, Representative The operating parameters at time The rate of change within Representative time The moment operating parameters, Representative time No. operating parameters, Represents time window Length of time; Based on the operating parameters of the relay equipment, the coil current, contact resistance, tripping current threshold and the number of relay protection logic triggering times are obtained. To ensure the time continuity of the data, short-term (e.g. 5 minutes), medium-term (e.g. 30 minutes) and long-term (e.g. 2 hours) time windows are set to store the operating parameter values ​​within the corresponding time ranges for subsequent calculations. The operating parameter data of each time window are arranged in time series to calculate the current moment. and the previous moment The difference in parameter values ​​is calculated using the formula: ; in, Representative time The operating parameter value at the moment, Represents the parameter value at the previous moment, is the time span of the current time window. For example, if Corresponding to the 30-minute time window, Minutes, the calculation results are used to measure the rate of change of operating parameters. In the actual example, if the coil current of the relay device was 5A 10 minutes ago and the current value rises to 5.5A, the rate of change of the coil current is: ; Similarly, the change rates of contact resistance, trip current threshold and relay protection logic trigger times are calculated, and all parameter change rate results are stored in the data set to form operating parameter change information.

[0021] S112: calling the operation parameter change information, calculating the change trend of each parameter in different time windows, and fitting the slope of the trend change by linear regression to obtain the operation state change slope; Call the operating parameter change information, calculate the change trend of each parameter in the short-term, medium-term and long-term time windows, use time series data to establish a trend model, obtain the trend value of each parameter changing over time, use linear regression method to fit the data, and calculate the slope , where the slope is calculated as: ; in, Representative The slope of the changing trend of the parameter in the current time window, is the number of sampling points in the time window, represents the mean of the time series, Representative The average rate of change of a parameter. For example, if the contact resistance is sampled 6 times in a 30-minute time window and the values ​​are 0.02Ω, 0.021Ω, 0.022Ω, 0.023Ω, 0.025Ω, and 0.026Ω respectively, then the average value is calculated as: ; Then calculate the mean of the time series: ; Substitute into the formula to calculate the slope , calculate the slope of the contact resistance change trend: ; Get the slope value , and obtain the slope of the running state change.

[0022] S113: Call the operating state change slope, and based on the mean and variance of each parameter change rate, screen the operating parameters whose change trend exceeds the preset change threshold, and calculate the parameter change rate ratio to obtain the relay equipment operating state change rate.

[0023] Call the running status change slope, calculate the change range based on the mean and variance of each parameter change rate, filter out parameters whose change trend exceeds the preset change threshold, and set the preset threshold range. The threshold is set as follows: Use statistical methods to calculate the average rate of change based on historical data of normally operating equipment and standard deviation ; Set a 95% confidence interval, that is: ; in, For the Preset change thresholds of various parameters; For example, if the mean value of the contact resistance change rate of the relay device is 0.022Ω and the standard deviation is 0.002Ω, calculate the threshold value: ; When the contact resistance change rate exceeds 0.026Ω, it is judged as an abnormal change and enters the screening list. All operating parameters that exceed the preset change threshold are screened and their change rate ratio is calculated using the normalized calculation method: ; in, Representative The change rate ratio of these parameters is calculated by substituting the parameters in the previous step into the calculation: ; The result shows that the change rate of contact resistance accounts for 23.4%, which is smaller than other parameters. By screening parameters whose change trend exceeds the threshold, the change rate of the operating status of the relay equipment is obtained.

[0024] See also Figure 3 , the specific steps for obtaining the health degradation rate of relay equipment are: S211: Based on the rate of change of the operating status of the relay equipment, the formula is: ; Calculate the health score and obtain the health information of the relay equipment; in, Represents the health score, Representative The current rate of change of the operating parameters, Representative The influence weight of various operating parameters, Represents the total number of operating parameters; Based on the rate of change of the operating status of the relay equipment, the health score is calculated. First, the current rate of change of each operating parameter is called , and introduce the corresponding influence weight The setting of the impact weight is based on the criticality of the equipment operation, the impact intensity on the relay protection system, and the historical statistical data of equipment failures. Among them, the weight of critical equipment (such as high-load relays) is higher, and the weight of non-critical equipment is lower. For example, the weight of high-load relays can be set to 0.4, while the weight of ordinary relays is set to 0.2. The formula is: ; Calculate health score and set total number of operating parameters , calculate the weighted rate of change of each parameter separately. For example, if the coil current change rate of the device is , contact resistance change rate , trip current threshold change rate , the rate of change of relay protection logic trigger times , the corresponding weights are 0.3, 0.3, 0.2, 0.2 respectively, then calculate:

[0025] ; The health score is calculated as , indicating that the relay equipment is relatively healthy, and the health information of the relay equipment is obtained.

[0026] S212: calling the health information of the relay equipment, setting the health threshold, screening the equipment whose health score is lower than the health threshold, obtaining the coil aging degree, contact wear degree and relay operation times of the equipment, and obtaining the equipment set whose health score is lower than the threshold; Call the relay equipment health information, set the health threshold, and filter the equipment whose health score is lower than the health threshold. The health threshold is set based on historical operation data and the threshold is calculated by the mean and standard deviation based on the normal operation status of the equipment. The setting method is as follows: Count the average health status of all normal operating devices and standard deviation ; Setting health thresholds ; If the device health score is lower than , then enter the low health screening set.

[0027] For example, the average historical health of the device , standard deviation ; Calculate the health threshold: ; If the health score calculated by a device (below 0.95), the device enters the low health screening set, and the coil aging degree, contact wear and relay operation times of the device are extracted through the operation log and equipment maintenance data, and stored in the device set with health below the threshold.

[0028] S213: Call the device set whose health is lower than the threshold, calculate the decay rate of the health score per unit time, and obtain the health decline rate of the relay device.

[0029] Call the device set whose health is lower than the threshold, calculate the decay rate of the health score per unit time, use the linear regression method to fit the health change trend, and calculate the health decline rate , calculated as ;in, Score your health at the current moment. Score the health level at the last moment. As the time interval, set the device to calculate the health once every 24 hours. If the health score of a device yesterday was 0.96 and the current health score is 0.94, then calculate: ; It indicates that the health degradation rate is 0.00083. If the absolute value of this value exceeds the preset health degradation warning threshold (for example, -0.001, the threshold is set by the average degradation rate plus twice the standard deviation of the health degradation rate), it is necessary to pay attention to the maintenance plan of the equipment and obtain the health degradation rate of the relay equipment.

[0030] See also Figure 4 ,The specific steps for obtaining the maintenance task priority list are: S311: Based on the health decline rate of the relay equipment, the health decline rate is compared with the preset attenuation threshold to determine whether the equipment needs to be maintained, and the equipment whose health decline rate is higher than the attenuation threshold is selected to obtain a set of equipment that needs maintenance; Based on the health decline rate of the relay equipment, compare it with the preset attenuation threshold to determine whether the equipment needs maintenance and obtain the health decline rate of each device. The rate is calculated by using the time change rate of the aforementioned health score and setting the decay threshold As the maintenance judgment benchmark, the threshold is set according to the health change range of the normally operating equipment. The setting method is as follows: Count the average health decline rate of all equipment in normal operation and standard deviation ; Set the health decay threshold ; If the device health decline rate is higher than , then enter the filter set of equipment that needs maintenance.

[0031] For example: Average health decline rate , standard deviation ; Calculate the health decay threshold: ; If the health degradation rate calculated by a device (higher than -0.0002), the device enters the set of devices requiring maintenance.

[0032] S312: Call the equipment set that needs maintenance, and use the formula based on the equipment importance weight parameter: ; Calculate the maintenance task priority for each device; in, Represents the equipment maintenance task priority, Represents the rate of health decline, Represents the importance weight of the device, Represents the change in health score, Represents the time period since the last maintenance of the equipment; Call the equipment set that needs maintenance, combine the equipment importance weight parameters, calculate the equipment maintenance task priority, equipment importance weight parameters The equipment is set according to its criticality in the relay protection system. Critical equipment (such as main relays) is given a higher weight, and common equipment is given a lower weight. The setting method is as follows: Equipment is classified according to the operation risk level and divided into importance levels, such as high priority , medium priority , low priority ; Calculate the change in equipment health score ; Calculate the time period since the last maintenance of the equipment , in hours; using the formula: ; Calculate equipment maintenance task priorities.

[0033] For example: Setting the rate at which the health of a device decreases , equipment importance weight , the change in health score , last maintenance interval Hours; Calculate equipment maintenance task priority: ; Get the equipment maintenance task priority.

[0034] S313: Calling the maintenance task priority of the equipment, sorting the equipment to be maintained according to the priority, and obtaining a maintenance task priority list.

[0035] Call the equipment maintenance task priority, sort the equipment that needs maintenance according to the priority, and prioritize all equipment Arrange in descending order. The larger the priority value, the higher the urgency of equipment maintenance. Generate a maintenance task priority list according to the sorting order. For example: equipment number A1, maintenance task priority 0.000550, ranking 1; equipment number B3, maintenance task priority 0.000520, ranking 2; equipment number C5, maintenance task priority 0.000405, ranking 3; finally, a maintenance task priority list is obtained.

[0036] See also Figure 5 , the specific steps for obtaining the maintenance adjustment amount of the relay equipment are: S411: Based on the maintenance task priority column, the load current, the number of disconnections and the flow time of the relay device are obtained, and the mean and standard deviation of the load change rate are calculated to obtain a load change rate statistical value; Based on the maintenance task priority list, obtain the load current, breaking times and flow time of the relay equipment, calculate the mean and standard deviation of the load change rate, and extract the load current from the historical operation data of the equipment , breaking times and flow time , calculate the load change rate of each device in different time periods, the calculation method is as follows: ; in, Represents a device at time The load change rate at and Represent the load current of the current and previous time periods respectively. Calculate the mean and standard deviation : ; ; For example: Equipment load current data: , , ; Calculate the load change rate: ; ; Calculate the mean load change rate: ; Calculate the standard deviation: ; Obtain the load change rate statistics.

[0037] S412: Call the load change rate statistics to determine the load fluctuation situation, and compare it with the preset load fluctuation threshold to determine whether the maintenance cycle needs to be adjusted, using the formula: ; Calculate adjusted maintenance intervals; in, represents the adjusted maintenance cycle, Represents the current maintenance cycle, Represents the standard deviation of the load change rate, Represents the mean value of the load change rate; Call the load change rate statistics to determine the load fluctuation and compare it with the preset load fluctuation threshold Compare and determine whether the maintenance cycle needs to be adjusted. The load fluctuation threshold is set as follows: the average load change rate of historical data and standard deviation ; Set the load fluctuation threshold ; If the currently calculated standard deviation Higher than , the maintenance cycle needs to be adjusted.

[0038] For example: Historical load change rate average , standard deviation ; Calculate the load fluctuation threshold: ; Current Standard Deviation (greater than 0.08), the maintenance cycle needs to be adjusted.

[0039] Using the formula: ; Set the current maintenance cycle Day, substitute: ; Calculate the adjusted maintenance cycle .

[0040] S413: Calling the adjusted maintenance cycle, calculating the required adjustment amount according to the current maintenance cycle, and obtaining the maintenance adjustment amount of the relay equipment.

[0041] Call the adjusted maintenance cycle and calculate the required adjustment amount as follows: ; For example: Maintenance cycle before adjustment Days, adjusted maintenance cycle Days; Calculate the adjustment: ; Get the relay equipment maintenance adjustment , the maintenance cycle is adjusted from 180 days to 201.6 days, and the maintenance adjustment amount of the relay equipment is obtained.

[0042] See also Figure 6 ,The specific steps for obtaining the relay equipment maintenance resource allocation information are: S511: Based on the maintenance adjustment amount of the relay equipment and the maintenance task priority list, the maintenance personnel demand of the relay protection relay is calculated, the number of maintenance tasks, the standard working hours of a single task and the available working hours resources are obtained, and the maintenance personnel demand information is obtained; Based on the maintenance adjustment of the relay equipment and the maintenance task priority list, determine the number of maintenance tasks that need to be completed, for example, plan Relay equipment is regularly maintained, and the standard working hours for each task are checked. Assume that the standard working hours for each task is Hours, count available man-hour resources, assuming that there are Maintenance personnel, each person can work per day hours, the total available work time resources are Hours, multiply the number of maintenance tasks by the standard working hours of a single task to get the total working hours required, that is, Hours, compare the total labor time demand with the available labor time resources. If the total labor time demand is greater than the available labor time resources, additional maintenance personnel are needed, otherwise the existing personnel are sufficient to complete the task.

[0043] S512: call the maintenance personnel demand information, combine the spare parts consumption of the equipment maintenance task, and combine the inventory status and safety reserve threshold, and use the formula: ; Calculate spare parts reserve requirements; in, represents the spare parts reserve demand, Representative Spare parts consumption rate of each type of equipment, Representative The maintenance cycle after the equipment is adjusted. Representative The supply rate of spare parts that can be replenished per unit time for this type of equipment, Represents the current inventory quantity, Represents the total number of devices; Call maintenance personnel demand information, combine spare parts consumption of equipment maintenance tasks, and calculate spare parts consumption rate of each equipment , for example, for Equipment, average maintenance consumption per time spare parts, determine the maintenance cycle of the equipment after adjustment , assuming the adjusted maintenance cycle is day, find out the supply rate of spare parts that can be replenished per unit time for this equipment , assuming that suppliers can provide Spare parts, pcs / day, calculate the number of spare parts required in a maintenance cycle, that is: ; At the same time, count the current inventory , assuming the current inventory is spare parts, using the formula: ; Calculate spare parts reserve requirements, indicating the need for additional reserves Spare parts.

[0044] S513: Call the spare parts reserve demand, combine it with the maintenance personnel demand, adjust the maintenance time window, optimize the task allocation, and obtain the relay equipment maintenance resource allocation information.

[0045] Call the spare parts reserve demand, combine it with the maintenance personnel demand, evaluate the arrangement of the current maintenance time window, and set the current maintenance time window as Monday to Friday. to ,Consider adjusting the maintenance time window, for example, extending daily working hours or adding weekend work to meet the needs of maintenance personnel, optimize task allocation, assign high-priority maintenance tasks to experienced maintenance personnel, and assign low-priority tasks to other personnel to ensure that tasks are reasonably allocated according to priority. Combined with the supply of spare parts, reasonably arrange the purchase and inventory of spare parts to ensure that there is sufficient supply of spare parts within the adjusted maintenance time window to avoid maintenance delays caused by spare parts shortages. After the above adjustments, the optimized allocation information of relay equipment maintenance resources is obtained.

[0046] A relay protection device predictive maintenance system, the relay protection device predictive maintenance system is used to execute the above relay protection device predictive maintenance method, the system comprises: The operation status analysis module calculates the change trend of each operation parameter in each time window based on the operation parameters of the relay equipment, and obtains the change rate of the operation status of the relay equipment; The health change analysis module calculates the health score of the relay device based on the change rate of the relay device's operating status, selects the devices whose health score is lower than the health threshold, calculates the health score decay rate per unit time, and obtains the health decline rate of the relay device; The maintenance task sorting module determines whether the equipment needs maintenance based on the health decline rate of the relay equipment, and calculates the equipment maintenance task priority based on the equipment importance weight parameter to obtain the maintenance task priority list; The maintenance cycle adjustment module obtains the load current, breaking times and flow time of the relay equipment based on the maintenance task priority list, calculates the mean and standard deviation of the load change rate, determines the load fluctuation, adjusts the maintenance cycle, and obtains the maintenance adjustment amount of the relay equipment; The maintenance resource scheduling module calculates the maintenance personnel demand and spare parts reserve demand of the relay protection relay based on the maintenance adjustment amount of the relay equipment and the maintenance task priority list, and adjusts the maintenance time window to obtain the maintenance resource allocation information of the relay equipment.

[0047] The above are only preferred embodiments of the present invention and are not intended to limit the present invention in other forms. Any technician familiar with the profession may use the technical contents disclosed above to change or modify them into equivalent embodiments with equivalent changes and apply them to other fields. However, any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present invention without departing from the technical solution of the present invention still falls within the protection scope of the technical solution of the present invention.

Claims

1. A predictive maintenance method for relay protection equipment, characterized in that: The following steps are involved: S1: Based on the operating parameters of the relay equipment, the change trend of each operating parameter in each time window is calculated to obtain the change rate of the operating state of the relay equipment; S2: Based on the change rate of the operating state of the relay device, calculate the health score of the relay device, select the devices whose health score is lower than the health threshold, calculate the decay rate of the health score per unit time, and obtain the health decline rate of the relay device; S3: Based on the health decline rate of the relay device, determine whether the equipment needs to be maintained, and calculate the equipment maintenance task priority in combination with the equipment importance weight parameter to obtain a maintenance task priority list; S4: Based on the maintenance task priority list, obtain the load current, breaking times and current flow time of the relay equipment, calculate the mean and standard deviation of the load change rate, determine the load fluctuation, adjust the maintenance cycle, and obtain the maintenance adjustment amount of the relay equipment; S5: Based on the relay equipment maintenance adjustment amount and the maintenance task priority list, the maintenance personnel demand and spare parts reserve demand of the relay protection relay are calculated, and the maintenance time window is adjusted to obtain the relay equipment maintenance resource allocation information.

2. The predictive maintenance method for relay protection equipment according to claim 1, characterized in that: The relay equipment operating state change rate includes the coil current change rate, the contact resistance increment rate, the tripping current threshold fluctuation trend and the protection logic trigger frequency change value; the relay equipment health decline rate includes the health score decay rate, the coil aging trend value, the contact wear growth amount and the relay action abnormality ratio; the maintenance task priority list includes the maintenance task sorting coefficient, the fault impact level coefficient, the health decline assessment value and the task execution urgency; the relay equipment maintenance adjustment amount includes the maintenance interval correction value, the load fluctuation impact coefficient, the maintenance plan adjustment time and the equipment maintenance level change information; the relay equipment maintenance resource allocation information includes the maintenance personnel demand, the spare parts reserve demand, the maintenance time window and the task execution work order number.

3. The predictive maintenance method for relay protection equipment according to claim 1, characterized in that: The steps for obtaining the rate of change of the operating state of the relay device are specifically as follows: S111: Based on the operating parameters of the relay equipment, the coil current, contact resistance, trip current threshold and the number of relay protection logic triggering are obtained, and short-term, medium-term and long-term time windows are set to calculate the data change rate of each operating parameter in each time window, using the formula: ； Calculate the change rate of the operating parameters in each time window to obtain the operating parameter change information; in, Representative The operating parameters at time The rate of change within Representative time The moment operating parameters, Representative time No. operating parameters, Represents time window Length of time; S112: calling the operation parameter change information, calculating the change trend of each parameter in different time windows, and fitting the slope of the trend change by linear regression to obtain the slope of the operation state change; S113: Call the operating state change slope, and according to the mean and variance of each parameter change rate, screen the operating parameters whose change trend exceeds the preset change threshold, and calculate the parameter change rate ratio to obtain the relay equipment operating state change rate.

4. The predictive maintenance method for relay protection equipment according to claim 1, characterized in that: The steps for obtaining the health degradation rate of the relay device are specifically as follows: S211: Based on the rate of change of the operating state of the relay device, the formula is used: ； Calculate the health score and obtain the health information of the relay equipment; in, Represents the health score, Representative The current rate of change of the operating parameters, Representative The influence weight of various operating parameters, Represents the total number of operating parameters; S212: calling the health information of the relay device, setting a health threshold, screening devices whose health scores are lower than the health threshold, obtaining information on the coil aging degree, contact wear degree and relay operation times of the devices, and obtaining a set of devices whose health scores are lower than the threshold; S213: Call the device set whose health is lower than the threshold, calculate the decay rate of the health score per unit time, and obtain the health decline rate of the relay device.

5. The predictive maintenance method for relay protection equipment according to claim 1, characterized in that: The steps for obtaining the maintenance task priority list are specifically as follows: S311: Based on the health decline rate of the relay device, the health decline rate is compared with the preset attenuation threshold to determine whether the device needs to be maintained, and the devices whose health decline rate is higher than the attenuation threshold are selected to obtain a set of devices that need maintenance; S312: Call the maintenance-required equipment set, and combine the equipment importance weight parameter to adopt the formula: ； Calculate the maintenance task priority for each device; in, Represents the equipment maintenance task priority, Represents the rate of health decline, Represents the importance weight of the device, Represents the change in health score, Represents the time period since the last maintenance of the equipment; S313: calling the maintenance task priority of the equipment, sorting the equipment to be maintained according to the priority, and obtaining a maintenance task priority list.

6. The predictive maintenance method for relay protection equipment according to claim 1, characterized in that: The steps for obtaining the maintenance adjustment amount of the relay equipment are specifically as follows: S411: Based on the maintenance task priority list, the load current, the number of disconnections and the flow time of the relay device are obtained, and the mean and standard deviation of the load change rate are calculated to obtain a load change rate statistical value; S412: Call the load change rate statistics to determine the load fluctuation situation, and compare it with the preset load fluctuation threshold to determine whether the maintenance cycle needs to be adjusted, using the formula: ； Calculate adjusted maintenance intervals; in, represents the adjusted maintenance cycle, Represents the current maintenance cycle, Represents the standard deviation of the load change rate, Represents the mean value of the load change rate; S413: calling the adjusted maintenance cycle, calculating the required adjustment amount according to the current maintenance cycle, and obtaining the maintenance adjustment amount of the relay equipment.

7. The predictive maintenance method for relay protection equipment according to claim 1, characterized in that: The steps for obtaining the relay equipment maintenance resource allocation information are specifically as follows: S511: Based on the maintenance adjustment amount of the relay equipment and the maintenance task priority list, calculate the maintenance personnel demand of the relay protection relay, obtain the number of maintenance tasks, the standard working hours of a single task and the available working time resources, and obtain the maintenance personnel demand information; S512: Call the maintenance personnel demand information, combine the spare parts consumption of the equipment maintenance task, and combine the inventory status and the safety reserve threshold, and use the formula: ； Calculate spare parts reserve requirements; in, represents the spare parts reserve demand, Representative Spare parts consumption rate of each type of equipment, Representative The maintenance cycle after the equipment is adjusted. Representative The supply rate of spare parts that can be replenished per unit time for this type of equipment, Represents the current inventory quantity, Represents the total number of devices; S513: The spare parts reserve demand is called, combined with the maintenance personnel demand, the maintenance time window is adjusted, the task allocation is optimized, and the relay equipment maintenance resource allocation information is obtained.

8. A predictive maintenance system for relay protection equipment, characterized in that: According to any one of claims 1 to 7, the predictive maintenance method for relay protection equipment comprises: The operation status analysis module calculates the change trend of each operation parameter in each time window based on the operation parameters of the relay equipment, and obtains the change rate of the operation status of the relay equipment; The health change analysis module selects devices whose health scores are lower than the health threshold based on the change rate of the operating state of the relay device, calculates the decay rate of the health score per unit time, and obtains the health decline rate of the relay device; The maintenance task sorting module determines whether the equipment needs to be maintained based on the health decline rate of the relay equipment, calculates the equipment maintenance task priority, and obtains a maintenance task priority list; The maintenance cycle adjustment module calculates the mean and standard deviation of the load change rate based on the maintenance task priority list, determines the load fluctuation, adjusts the maintenance cycle, and obtains the maintenance adjustment amount of the relay equipment; The maintenance resource scheduling module calculates the maintenance personnel demand and spare parts reserve demand of the relay protection relay based on the relay equipment maintenance adjustment amount and the maintenance task priority list, and adjusts the maintenance time window to obtain the relay equipment maintenance resource allocation information.

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