Automatic voltage regulator acceleration reliability test method

Abstract

The invention discloses an accelerated reliability test method for an automatic voltage regulator, relates to the technical field of reliability tests, and aims to solve the problems of long time consumption and low test efficiency of reliability tests of the automatic voltage regulator in design and production stages in the prior art. According to reliability index requirements of the automatic voltage regulator, reliability time is predicted, the number of samples of the automatic voltage regulator is selected, the control range of temperature and humidity is determined, reliability calculation is carried out, and reasonable reliability test time, the number of samples, the number of receivable faults and the value of high-temperature and high-humidity acceleration factors are determined. Initial detection is carried out on all the automatic voltage regulator samples, the initial detection comprises whether performance indexes and the like of the voltage regulator are normal or not, and reliability testing is carried out on the automatic voltage regulator samples. According to the invention, the reliability test time of the automatic voltage regulator can be effectively shortened, and the reliability test efficiency is improved.

Description

Technical Field

[0001] The invention relates to the technical field of reliability testing, and in particular to an accelerated reliability testing method for an automatic voltage regulator. Background Art

[0002] An automatic voltage regulator is a synchronous generator regulator that maintains the voltage of the synchronous generator at a predetermined value or changes the terminal voltage according to a plan. When the terminal voltage, reactive power, etc. of the synchronous motor change, the output current of the exciter is automatically controlled according to the corresponding feedback signal to achieve the purpose of automatically adjusting the terminal voltage or reactive power of the synchronous motor. Since the transmission ratio between the generator and the engine is fixed, the speed of the generator will change with the change of the engine speed. During the operation of the car, the engine speed varies in a wide range, and the terminal voltage of the generator will also vary in a wide range with the change of the engine speed. The generator requires its voltage to be stable when supplying power to electrical equipment and charging the battery. Therefore, in order to keep the voltage at a certain value basically unchanged, the output voltage of the generator must be adjusted.

[0003] According to the reliability index requirements, it takes several months or even longer to test a newly designed or modified automatic voltage regulator according to the conventional reliability process. Based on the existing technology, the reliability test of the automatic voltage regulator in the design and production stages consumes a long time and the test efficiency is low. Summary of the invention

[0004] The invention provides an accelerated reliability test method for an automatic voltage regulator, which solves the problem in the prior art that the reliability test of the automatic voltage regulator in the design and production stages consumes a long time and has low test efficiency.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] An accelerated reliability test method for an automatic voltage regulator comprises the following steps:

[0007] Step S1: according to the reliability index requirements of the automatic voltage regulator, the reliability time is estimated, the number of automatic voltage regulator samples is selected, the control range of temperature and humidity is determined, reliability calculation is performed, and a reasonable reliability test time, sample quantity, acceptable number of failures, and acceleration factor value of applying high temperature and high humidity are determined;

[0008] Step S2: Performing an initial test on all automatic voltage regulator samples, including whether the performance indicators of the voltage regulators are normal;

[0009] Step S3: performing a high temperature and high humidity reliability test on the automatic voltage regulator samples that have passed the initial test;

[0010] Step S4: After the reliability test is completed, retest all automatic voltage regulator samples with the same initial test items;

[0011] Step S5: if the number of faults detected by the recheck does not exceed the acceptable number of faults, it is determined that the automatic voltage regulator meets the reliability requirements;

[0012] Step S6: If the number of faults detected by the re-test exceeds the acceptable number of faults (the acceptable number of faults is not met for the first time), the acceptable number of faults is increased, and other parameters such as the acceleration factor value remain unchanged. After determining the increased reliability test running time, the reliability test and re-test are continued.

[0013] Step S7: If the acceptable number of faults after the reliability test still exceeds the expected number of faults and the acceptable number of faults requirement is not met for the second time, a fault analysis of the automatic voltage regulator is performed, and the test is repeated after the fault is repaired.

[0014] Preferably, in step S1, the reliability index MTBF of the automatic voltage regulator is 12893 hours, the reliability time is expected to be controlled within 15 days, 20 automatic voltage regulators are selected for reliability testing, the temperature is controlled at 75±5°C, and the relative humidity is controlled at ≥95%.

[0015] Preferably, the automatic voltage regulator samples in step S2 are the number of samples calculated in step S1.

[0016] Preferably, in step S3, the temperature range is 75±5° C., the relative humidity is ≥95%, and the initial reliability test days are 13 days.

[0017] Preferably, if the number of faults detected by the recheck in step S5 is ≤1 and does not exceed the expected acceptable number of faults by 1, it is determined that the automatic voltage regulator meets the reliability requirement.

[0018] Preferably, in step S6, if the number of faults detected by the re-inspection is greater than 1, exceeding the acceptable number of faults by 1 (the acceptable number of faults is not met for the first time), the acceptable number of faults is increased to 2, and other parameters such as the acceleration factor value remain unchanged. The increased reliability test running time is determined to be increased by 6 days, and the reliability test and re-inspection are continued.

[0019] Preferably, in step S7, if the acceptable fault number after the reliability test still exceeds the acceptable fault number 2 (the acceptable fault number requirement is not met for the second time), a fault analysis of the automatic voltage regulator is performed, and the test is performed again after the fault is repaired.

[0020] The beneficial effects of the present invention are:

[0021] When conducting reliability tests on automatic voltage regulators, the temperature during the tests is maintained at 75±5°C, the relative humidity is controlled at ≥95%, the number of faults detected by re-testing is ≤1, and does not exceed the expected acceptable number of faults by 1, then the automatic voltage regulator is determined to meet the reliability requirements, if the number of faults detected by re-testing is greater than 1, exceeding the acceptable number of faults by 1 (the acceptable number of faults is not met for the first time), then the acceptable number of faults is increased to 2, other parameters such as the acceleration factor value remain unchanged, and the increased reliability test running time is determined to be increased by 6 days, and reliability tests and re-tests are continued, if the acceptable number of faults after the reliability test still exceeds the acceptable number of faults by 2 (the acceptable number of faults is not met for the second time), then a fault analysis of the automatic voltage regulator is performed, and the test is repeated after the fault is repaired, and a reliability test method with high temperature and high humidity stress is provided when conducting reliability tests on automatic voltage regulators, which can effectively shorten the reliability test time of the automatic voltage regulator and improve the reliability test efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 The present invention provides a flow chart of an accelerated reliability test method for an automatic voltage regulator. DETAILED DESCRIPTION

[0023] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0024] Example 1, reference Figure 1 , an accelerated reliability test method for an automatic voltage regulator, comprising the following steps:

[0025] Step S1: According to the reliability index requirements of the automatic voltage regulator, the reliability time is estimated, the number of automatic voltage regulator samples is selected, the control range of temperature and humidity is determined, and reliability calculation is performed to determine the reasonable reliability test time, sample number, acceptable number of failures, and acceleration factor value of applying high temperature and high humidity. The reliability index MTBF of the automatic voltage regulator is 12893 hours, and the reliability time is expected to be controlled within 15 days. 20 automatic voltage regulators are selected for reliability testing, the temperature is controlled at 75±5℃, and the relative humidity is controlled at ≥95%. After reliability calculation, it is obtained that the reliability test acceleration factor is 4.55, the estimated time is 13 days, the estimated number of acceptable failures is 1, and the number of samples is 20;

[0026] Step S2: Performing an initial test on all automatic voltage regulator samples, including whether the performance indicators of the voltage regulator are normal, and the number of automatic voltage regulator samples is the number of samples calculated in step S1;

[0027] Step S3: Performing a high temperature and high humidity reliability test on the automatic voltage regulator samples that have passed the initial test, with the temperature controlled at 75±5°C and the relative humidity controlled at ≥95%;

[0028] Step S4: After the reliability test is completed, all automatic voltage regulator samples are retested for the same items as the initial test, with the test temperature range being 75±5°C and the relative humidity being ≥95%, and the initial reliability test duration being 13 days;

[0029] Step S5: if the number of faults detected by the re-test does not exceed the acceptable number of faults, it is determined that the automatic voltage regulator meets the reliability requirements; if the number of faults detected by the re-test is ≤1 and does not exceed the expected acceptable number of faults by 1, it is determined that the automatic voltage regulator meets the reliability requirements;

[0030] Step S6: If the number of faults detected by the re-inspection exceeds the acceptable number of faults (the acceptable number of faults is not met for the first time), the acceptable number of faults is increased, and other parameters such as the values ​​of acceleration factors remain unchanged. After determining the increased reliability test running time, the reliability test and re-inspection are continued. If the number of faults detected by the re-inspection is greater than 1 and exceeds the acceptable number of faults by 1 (the acceptable number of faults is not met for the first time), the acceptable number of faults is increased to 2, and other parameters such as the values ​​of acceleration factors remain unchanged. It is determined that the increased reliability test running time is increased by 6 days, and the reliability test and re-inspection are continued.

[0031] Step S7: If the acceptable number of faults after the reliability test still exceeds the expected number of faults and the acceptable number of faults is not met for the second time, a fault analysis of the automatic voltage regulator is performed, and the test is performed again after the fault is repaired. If the acceptable number of faults after the reliability test still exceeds the acceptable number of faults by 2 (the acceptable number of faults is not met for the second time), a fault analysis of the automatic voltage regulator is performed, and the test is performed again after the fault is repaired.

[0032] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0033] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0034] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. An accelerated reliability test method for an automatic voltage regulator, characterized in that: The following steps are involved: Step S1: according to the reliability index requirements of the automatic voltage regulator, the reliability time is estimated, the number of automatic voltage regulator samples is selected, the control range of temperature and humidity is determined, reliability calculation is performed, and a reasonable reliability test time, sample quantity, acceptable number of failures, and acceleration factor value of applying high temperature and high humidity are determined; Step S2: Performing an initial test on all automatic voltage regulator samples, including whether the performance indicators of the voltage regulators are normal; Step S3: performing a high temperature and high humidity reliability test on the automatic voltage regulator samples that have passed the initial test; Step S4: After the reliability test is completed, retest all automatic voltage regulator samples with the same initial test items; Step S5: if the number of faults detected by the re-test does not exceed the acceptable number of faults, it is determined that the automatic voltage regulator meets the reliability requirements; Step S6: If the number of faults detected by the re-test exceeds the acceptable number of faults (the acceptable number of faults is not met for the first time), the acceptable number of faults is increased, and other parameters such as the acceleration factor value remain unchanged. After determining the increased reliability test running time, the reliability test and re-test are continued. Step S7: If the acceptable number of faults after the reliability test still exceeds the expected number of faults and the acceptable number of faults requirement is not met for the second time, a fault analysis of the automatic voltage regulator is performed, and the test is repeated after the fault is repaired.

2. The method for accelerating reliability testing of an automatic voltage regulator according to claim 1, characterized in that: In step S1, the reliability index MTBF of the automatic voltage regulator is 12893 hours, and the reliability time is expected to be controlled within 15 days. 20 automatic voltage regulators are selected for reliability test, the temperature is controlled at 75±5° C., and the relative humidity is controlled at ≥95%.

3. The method for accelerating reliability testing of an automatic voltage regulator according to claim 1, characterized in that: The number of automatic voltage regulator samples in step S2 is the number of samples calculated in step S1.

4. The method for accelerating reliability testing of an automatic voltage regulator according to claim 1, characterized in that: In step S3, the temperature range is 75±5° C., the relative humidity is ≥95%, and the initial reliability test days are 13 days.

5. The method for accelerating reliability testing of an automatic voltage regulator according to claim 1, characterized in that: If the number of faults detected by the recheck in step S5 is ≤ 1 and does not exceed the expected acceptable number of faults by 1, it is determined that the automatic voltage regulator meets the reliability requirements.

6. The method for accelerating reliability testing of an automatic voltage regulator according to claim 1, characterized in that: In step S6, if the number of faults detected by the re-inspection is greater than 1, which exceeds the acceptable number of faults by 1 (the acceptable number of faults is not met for the first time), the acceptable number of faults is increased to 2, and other parameters such as the acceleration factor value remain unchanged. The reliability test running time is increased by 6 days, and the reliability test and re-inspection are continued.

7. The method for accelerating reliability testing of an automatic voltage regulator according to claim 1, characterized in that: In step S7, if the acceptable fault number after the reliability test still exceeds the acceptable fault number 2 (the acceptable fault number requirement is not met for the second time), a fault analysis of the automatic voltage regulator is performed, and the test is performed again after the fault is repaired.

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