Electronic equipment preventive maintenance strategy development method considering performance degradation prediction error

Abstract

The invention discloses an electronic equipment preventive maintenance strategy development method considering a performance degradation prediction error. The method comprises the following steps: S1, carrying out an electronic equipment performance degradation prediction verification test; s2, determining a performance degradation prediction error interval; s3, constructing a maintenance cost model; s4, calculating the maintenance cost under different predicted errors; and S5, determining an optimal maintenance strategy. According to the invention, an effective maintenance strategy suitable for all performance degradation prediction errors can be obtained, and the maintenance cost is reduced. In a three-phase inverter application case, compared with a maintenance strategy which does not consider a performance degradation prediction error, the maintenance strategy determined by the method provided by the invention has the advantages that the lowest maintenance cost is obtained, and meanwhile, faults are avoided.

Description

Technical Field

[0001] The present invention belongs to the field of electronic equipment maintenance, and relates to a method for developing a preventive maintenance strategy for electronic equipment, and specifically relates to a method for developing a preventive maintenance strategy for electronic equipment that takes into account performance degradation prediction errors. Background Art

[0002] After long-term operation, electronic equipment will experience performance degradation, which will reduce operational stability and increase the risk of failure. Based on the predicted results of electronic equipment performance degradation, maintenance strategies can be developed to ensure long-term reliable operation of electronic equipment. However, due to the error between the predicted results of performance degradation and the actual degradation results, electronic equipment maintenance strategies that do not consider the predicted error of performance degradation may lead to increased maintenance costs or failure to operate stably in the long term due to equipment failure. Summary of the invention

[0003] The purpose of the present invention is to provide a method for developing a preventive maintenance strategy for electronic equipment taking into account performance degradation prediction errors, aiming to solve the inaccurate maintenance strategy for electronic equipment caused by performance degradation prediction errors, thereby reducing maintenance costs and the risk of long-term stable operation of equipment.

[0004] The objective of the present invention is achieved through the following technical solutions:

[0005] A method for developing a preventive maintenance strategy for electronic equipment considering performance degradation prediction errors comprises the following steps:

[0006] Step S1, conducting a predicted verification test of electronic equipment performance degradation;

[0007] Step S2, determining the expected error range of performance degradation;

[0008] Step S3: constructing a maintenance cost model;

[0009] Step S4, calculating the maintenance cost under different estimated errors;

[0010] Step S5: Determine the optimal maintenance strategy.

[0011] Compared with the prior art, the present invention has the following advantages:

[0012] 1. The present invention can avoid catastrophic failure of electronic equipment caused by neglecting performance degradation prediction errors in developing maintenance strategies, and achieve high reliability and long life operation of electronic equipment.

[0013] 2. The present invention can greatly improve the practicality and robustness of maintenance strategies by quantitatively analyzing the estimated error and incorporating it into the maintenance decision-making process. For the estimated error within a certain range, the present invention can determine the maintenance plan with the best comprehensive cost.

[0014] 3. The present invention can obtain an effective maintenance strategy applicable to all performance degradation prediction errors and reduce maintenance costs.

[0015] 4. In the three-phase inverter application case, the maintenance strategy determined by the method of the present invention avoids the occurrence of failures while obtaining the lowest maintenance cost, compared with the maintenance strategy that does not consider the performance degradation prediction error. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 Schematic diagram of the process for developing a preventive maintenance strategy for electronic equipment considering performance degradation prediction errors.

[0017] Figure 2 This is a graph showing the cost results of each maintenance strategy calculated when the estimated error of the embodiment is 0.5.

[0018] Figure 3 This is a graph showing the union results of effective maintenance strategies for different estimated errors in the implementation example.

[0019] Figure 4 This is a cost result diagram of each maintenance strategy without considering the estimated error in the embodiment. DETAILED DESCRIPTION

[0020] The technical solution of the present invention is further described below in conjunction with the accompanying drawings, but is not limited thereto. Any modification or equivalent replacement of the technical solution of the present invention without departing from the spirit and scope of the technical solution of the present invention should be included in the protection scope of the present invention.

[0021] The present invention provides a method for developing a preventive maintenance strategy for electronic equipment taking into account performance degradation prediction errors, such as Figure 1 As shown, the method comprises the following steps:

[0022] Step S1: Conducting electronic equipment performance degradation prediction verification test:

[0023] The total duration of the expected verification test of electronic equipment performance degradation is t a , a total of n test samples, measuring the parameters P of each sample at different times t i (t), where i is the i-th sample, 1≤i≤n, n≥5, 0≤t≤t a .

[0024] Step S2: Determine the expected error range of performance degradation:

[0025] Step S21: Calculate the degradation increment D of each sample at time t of the test. e,i (t):

[0026] D e,i (t)=|P i (t)-P i,0

[0027] Among them, P i,0 is the initial value of the parameter before the start of the i-th sample test.

[0028] Step S22: Use the Bootstrap method to calculate the degradation increment D under the significant level α at time t of the experiment. eL (t) is the lower bound, the degenerate increment D eU (t) is the upper bound of the degenerate increment mean interval [D eL (t),D eU (t)].

[0029] Step S23, calculating the expected performance degradation error e interval:

[0030]

[0031] Among them, D p (t) is the estimated mean incremental degradation value of the electronic equipment parameters at time t.

[0032] Step S3: Construct maintenance cost model:

[0033] Step S31: Determine the cost C of each inspection i .

[0034] Step S32: Determine the cost C of each maintenance m .

[0035] Step S33, set maintenance strategy: the electronic equipment is regularly inspected at the inspection interval Δt, and when the equipment parameter degradation increment is greater than or equal to the maintenance threshold D m Maintenance is performed during the entire operating time of the electronic equipment. w To ensure that the parameter degradation increment does not exceed the failure threshold D f .

[0036] Step S34: Establish a maintenance cost model as the total cost:

[0037] C=N i C i +N m C m

[0038] Among them, N i The total running time t w The number of checks within, N m The number of maintenance times.

[0039] Step S4: Calculate the maintenance cost under different estimated errors:

[0040] Step S41: Setting the maintenance threshold value range D m =[DmL ,D mU ], and take A values ​​evenly within this range.

[0041] Step S42: Set the inspection interval Δt to a value range of Δt=[Δt L ,Δt U ], and evenly take B values ​​within this range.

[0042] Step S42, uniformly taking C values ​​within the interval of the performance degradation prediction error e determined in step S23.

[0043] Step S43: Maintain the threshold D m , inspection interval Δt, and performance degradation prediction error e are combined to obtain A×B×C situations. For each situation, steps S44 to S410 are performed.

[0044] Step S44: Setting the failure threshold D f 、Maintenance times N m =0, parameters used for counting m=1, h=0.

[0045] Step S45, calculate the total number of inspections:

[0046]

[0047] Step S46: Calculate the degradation increment of the electronic device during the mth inspection as (1+e)D p [(mh)Δt].

[0048] Step S47: determine whether the degradation increment of the electronic device exceeds the failure threshold D at this time. f If it exceeds, the calculation is stopped. This maintenance threshold D m , inspection interval Δt, and estimated error e are invalid. Otherwise, it is a valid combination, and the process goes to step S48.

[0049] Step S48: Determine whether the degradation increment of the electronic device exceeds the maintenance threshold D at this time. m If exceeded, maintenance is required. m =N m +1, h=m. Otherwise, no maintenance is performed.

[0050] Step S49, update count m=m+1.

[0051] Step S410: Determine whether m is greater than the total number of inspections N. i If it is greater, the cost is calculated according to the cost model of step S34. Otherwise, steps S46 to S410 are repeated.

[0052] Step S5: Determine the optimal maintenance strategy:

[0053] Step S51: determine the effective maintenance threshold D under C different performance degradation prediction errors e m , check the union of interval Δt combinations.

[0054] Step S52: Calculate the same maintenance threshold D under C different performance degradation prediction errors e m , the sum of costs calculated at the inspection interval Δt.

[0055] Step S53: Maintenance threshold D with minimum total cost m , the inspection interval Δt is the optimal maintenance strategy.

[0056] Example:

[0057] This embodiment takes a three-phase inverter as an object to develop an electronic equipment preventive maintenance strategy that takes into account the performance degradation prediction error.

[0058] S1. Conduct prediction and verification tests on performance degradation of electronic equipment.

[0059] The three-phase inverter performance degradation prediction verification test is carried out at 80℃ for a total time of t a =4000 hours, with n=10 test samples in total, and the effective value of phase A current of each sample is measured at different times t at intervals of about 166 hours.

[0060] Step S2: Determine the expected error range of performance degradation.

[0061] Step S21: Calculate the degradation increment D of each sample at time t of the test. e,i (t).

[0062] Step S22: Use the Bootstrap method to calculate the degradation increment D under the significant level α at time t of the experiment. eL (t) is the lower bound, the degenerate increment D eU (t) is the upper bound of the degenerate increment mean interval [D eL (t),D eU (t)]. Taking 4000 hours as an example, the mean interval of degradation increment obtained by Bootstrap method at the significance level α = 0.05 is [0.0995, 0.1383].

[0063] Step S23, calculate the interval of the expected error e. Take 4000 hours as an example, the expected mean value is 0.0635 at this time. According to the mean interval of the actual degradation increment in the test, the error interval can be calculated as [0.565, 1.175]. Calculate the expected error interval at different times, take the minimum lower bound and the maximum upper bound, and you can get the interval containing the expected errors at all test times, here take [0.5, 1.2].

[0064] Step S3: construct a maintenance cost model.

[0065] Step S31: Determine the cost C of each inspection i =20.

[0066] Step S32: Determine the cost C of each maintenance m =38.

[0067] Step S33: Set the maintenance strategy as follows: perform regular inspections on the electronic equipment at an inspection interval Δt. When the increment of equipment parameter degradation is greater than or equal to the maintenance threshold D m Maintenance is performed during the entire operating time of the electronic equipment. w = Within 10 years, ensure that the parameter degradation increment does not exceed the failure threshold D f =0.3.

[0068] Step S34: Establish a maintenance cost model as the total cost.

[0069] Step S4: Calculate the maintenance cost under different estimated errors.

[0070] Step S41: Setting the maintenance threshold value range D m = [0.11, 0.3], and A = 20 values ​​are uniformly taken within this range (with an interval of 0.01).

[0071] Step S42, setting the inspection interval Δt value range Δt = [1,700], and evenly taking B = 700 values ​​within this range (with 1 day as the interval).

[0072] Step S42, in step S23, determine the estimated error e = [0.5, 1.2] and evenly take C = 8 values ​​(with an interval of 0.1).

[0073] Step S43: Maintain the threshold D m , the inspection interval Δt, and the estimated error e are combined to obtain 20×700×8 situations. For each situation, steps S44 to S410 are performed.

[0074] Step S44: Setting the failure threshold D f =0.3, maintenance times N m =0, parameters used for counting m=1, h=0.

[0075] Step S45, calculating the total number of inspections. Taking the case of Δt=2 days as an example, the total number of inspections 365÷2 is rounded down to 182 times.

[0076] Step S46: Calculate the degradation increment of the electronic device during the mth inspection as (1+e)D p [(mh)Δt].

[0077] Step S47: determine whether the degradation increment of the electronic device exceeds the failure threshold D at this time. f If it exceeds, the calculation is stopped. This maintenance threshold D m , check interval Δt, and estimated error e are invalid. Otherwise, it is a valid combination and proceed to the next step.

[0078] Step S48: Determine whether the degradation increment of the electronic device exceeds the maintenance threshold D at this time. m If exceeded, maintenance is required. m =N m +1, h=m. Otherwise, no maintenance is performed.

[0079] Step S49, update count m=m+1.

[0080] Step S410: Determine whether m is greater than the total number of inspections N. i If it is greater, the cost is calculated according to the cost model of step S34. Otherwise, steps S46 to S410 are repeated.

[0081] The cost result obtained with e = 0.5 is as follows Figure 2 As shown in Figure 2, the white area is the invalid maintenance measurement, which will cause the degradation increment during operation to exceed the failure threshold D. f =0.3.

[0082] Step S5: Determine the optimal maintenance strategy.

[0083] Step S51: Determine the effective maintenance threshold D under C different estimated errors e m , check the union of interval Δt combinations.

[0084] Step S52: Calculate the same maintenance threshold D under different estimated errors e m , the sum of costs calculated at the inspection interval Δt.

[0085] Step S53: Maintenance threshold D with minimum total cost m , the inspection interval Δt is the optimal maintenance strategy.

[0086] like Figure 3 As shown, taking the union of the results obtained by e = 0.5 and e = 1.2 as an example, the minimum cost is Δt = 513, D m =[0.11,0.13]. That is, according to the inspection interval Δt=513, the maintenance threshold D m =[0.11,0.13] for maintenance can obtain the minimum maintenance cost for any situation where the estimated error belongs to [0.5,1.2].

[0087] Without considering the estimated error, that is, e = 0, the cost calculation result is as follows Figure 4 As shown. The minimum cost is in D m =0.11, Δt=[609,716]. This result is not included in the cost result union considering the expected error, which means that maintenance with this strategy will result in failure to meet the 10-year work requirement. During operation, the degradation increment is greater than 0.3, and three inverters fail.

[0088] It can be seen that the maintenance strategy that considers the predicted error of performance degradation avoids electronic equipment failures, improves equipment operation stability and reduces maintenance costs.

Claims

1. A method for developing a preventive maintenance strategy for electronic equipment considering performance degradation prediction errors, characterized in that The method comprises the following steps: Step S1, conducting a predicted verification test of electronic equipment performance degradation; Step S2, determining the expected error range of performance degradation; Step S3: constructing a maintenance cost model; Step S4, calculating the maintenance cost under different estimated errors; Step S5: Determine the optimal maintenance strategy.

2. The method for developing a preventive maintenance strategy for electronic equipment considering performance degradation prediction errors according to claim 1, characterized in that In step S1, the total duration of the expected verification test of electronic equipment performance degradation is t a , a total of n test samples, measuring the parameters P of each sample at different times t i (t), where i is the i-th sample, 1≤i≤n, n≥5, 0≤t≤t a .

3. The method for developing a preventive maintenance strategy for electronic equipment considering performance degradation prediction errors according to claim 2, characterized in that The specific steps of step S2 are as follows: Step S21: Calculate the degradation increment D of each sample at time t of the test. e,i (t): D e,i (t)=|P i (t)-P i,0 | Among them, P i,0 is the initial value of the parameter before the start of the i-th sample test; Step S22: Use the Bootstrap method to calculate the degradation increment D under the significant level α at time t of the experiment. eL (t) is the lower bound, the degenerate increment D eU (t) is the upper bound of the degenerate increment mean interval [D eL (t),D eU (t)]; Step S23, calculating the expected performance degradation error e interval: Among them, D p (t) is the estimated mean incremental degradation value of the electronic equipment parameters at time t.

4. The method for developing a preventive maintenance strategy for electronic equipment considering performance degradation prediction errors according to claim 3, characterized in that The specific steps of step S3 are as follows: Step S31: Determine the cost C of each inspection i ; Step S32: Determine the cost C of each maintenance m ; Step S33, set maintenance strategy: the electronic equipment is regularly inspected at the inspection interval Δt, and when the equipment parameter degradation increment is greater than or equal to the maintenance threshold D m Maintenance is performed during the entire operating time of the electronic equipment. w To ensure that the parameter degradation increment does not exceed the failure threshold D f ; Step S34: Establish a maintenance cost model as the total cost: C=N i C i +N m C m Among them, N i The total running time t w The number of checks within, N m The number of maintenance times.

5. The method for developing a preventive maintenance strategy for electronic equipment considering performance degradation prediction errors according to claim 4, characterized in that The specific steps of step S4 are as follows: Step S41: Setting the maintenance threshold value range D m =[D mL ,D mU ], taking A values ​​evenly within this range; Step S42: Set the inspection interval Δt to a value range of Δt=[Δt L ,Δt U ], and evenly take B values ​​within this range; Step S42, uniformly taking C values ​​within the interval of the performance degradation prediction error e determined in step S23; Step S43: Maintain the threshold D m , inspection interval Δt, performance degradation prediction error e are combined to obtain A×B×C situations, and steps S44 to S410 are performed for each situation; Step S44: Setting the failure threshold D f 、Maintenance times N m =0, parameters for counting m=1, h=0; Step S45, calculate the total number of inspections: Step S46: Calculate the degradation increment of the electronic device during the mth inspection as (1+e)D p [(mh)Δt]; Step S47: determine whether the degradation increment of the electronic device exceeds the failure threshold D at this time. f If it exceeds, the calculation is stopped. This maintenance threshold D m , the combination of the inspection interval Δt and the estimated error e is invalid, otherwise, it is a valid combination, and the process goes to step S48; Step S48: Determine whether the degradation increment of the electronic device exceeds the maintenance threshold D at this time. m , if exceeded, maintenance is performed, N m =N m +1, h=m, otherwise, no maintenance is performed; Step S49, update count m=m+1; Step S410: Determine whether m is greater than the total number of inspections N. i If it is greater, calculate the cost according to the cost model of step S34; otherwise, repeat steps S46 to S410.

6. The method for developing a preventive maintenance strategy for electronic equipment considering performance degradation prediction errors according to claim 5, characterized in that The specific steps of step S5 are as follows: Step S51: Determine the effective maintenance threshold D under C different performance degradation prediction errors e m , check the union of interval Δt combinations; Step S52: Calculate the same maintenance threshold D under C different performance degradation prediction errors e m , the sum of costs calculated at the inspection interval Δt; Step S53: Maintenance threshold D with minimum total cost m , the inspection interval Δt is the optimal maintenance strategy.

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