CN104076224B - A kind of test method of power information collecting device reliability demonstration - Google Patents

Abstract

The present invention provides a kind of test method of power information collecting device reliability demonstration, comprises the following steps：Power information collecting device reliability model is set up, failure mode, failure criteria and failure statistics principle is determined；Power information collecting device humiture stress accelerated life test is carried out, and carries out failure statistics；The test data that accelerated life test is obtained is analyzed, and obtains cumulative failure probability and reliability.The test method of the power information collecting device reliability demonstration that the present invention is provided, to set up the reliability model of power information collecting device, instruct the development of power information collecting device humiture stress accelerated life test, and the estimate of characteristic quantities under regular service conditions is derived from the fail data under acceleration environment, verify whether the reliability of power information collecting device meets requirement.

Description

A kind of test method of power information collecting device reliability demonstration

Technical field

The present invention relates to a kind of test method, in particular to a kind of experiment of power information collecting device reliability demonstration Method.

Background technology

In power information acquisition system construction, because system scale is big, collection device type is more, and running environment is various, Continuous operating time is long, and communication media and communication protocol are complicated, and the integrity problem of collecting device is increasingly protruded, so as to restrict The promotion and application of acquisition system.

In order to realize the target of power information acquisition system all standing and full collection, it is desirable to which collecting device can be in various operations Under environment (including electromagnetic environment, climatic environment etc.), run stably in a long term.Meanwhile, the work(that power information acquisition system is realized The vital interests of enterprise are can relate to, in order to ensure the safety of energy data and complete, it is desirable to which collecting device has reliability very high Property.

Power information collecting device is used to be acquired the power information of each information gathering point, it is possible to achieve electric energy meter number According to collection, data management, data double-way transmission and forwarding or perform control command.It is divided into special transformer acquisition terminal by application places The types such as end, centralized automatic meter-reading terminal (including concentrator, collector), distributed energy monitor terminal.Power information collecting device Reliability engineering research and application it is still at an early stage, most of collecting device manufacturer design, component select With lack the guarantee to reliability in production technology, the reliability of equipment is verified without effective method also.

Power information collecting device carries out life test in normal conditions of use, it is difficult to obtain failure number in a short time According to.To shorten test period, test sample number and testing expenses being reduced, using accelerated life test.In practice, collecting device leads to The influence of various stress, such as temperature, humidity are subjected to, and with Multiple Failure Modes, such as communication failure, electric energy meter data Copy and accept failure, analog measurement error overproof etc., the accelerated life test of collecting device has many stress and multi-invalidation mode Feature.

The content of the invention

In order to overcome the above-mentioned deficiencies of the prior art, the present invention provides a kind of power information collecting device reliability demonstration Test method, to set up the reliability model of power information collecting device, instruct power information collecting device humiture it is constant should The development of power accelerated life test, and from the fail data under acceleration environment derive regular service conditions under characteristic quantities Estimate, verify power information collecting device reliability whether meet requirement.

In order to realize foregoing invention purpose, the present invention is adopted the following technical scheme that：

The present invention provides a kind of test method of power information collecting device reliability demonstration, and methods described includes following step Suddenly：

Step 1：Power information collecting device reliability model is set up, failure mode, failure criteria and failure statistics are determined Principle；

Step 2：Power information collecting device humiture stress accelerated life test is carried out, and carries out failure statistics；

Step 3：The test data that accelerated life test is obtained is analyzed, and obtains cumulative failure probability and reliability Degree.

The step 1 is comprised the following steps：

Step 1-1：Set up power information collecting device reliability model；

Step 1-2：Determine power information collecting device reliability demonstration requirement；

Step 1-3：Determine failure criteria, failure mode and failure statistics principle.

In the step 1-1, power information collecting device includes power module, main control module, interface module, AC sampling Module, display module, communication module and security module；Power information collecting device reliability model is series model, uses telecommunications Any Module Fail in breath collecting device, power information collecting device occurs as soon as failure, the test specimen failed in experiment Do not repaired.

In the step 1-2, power information collecting device reliability demonstration index is specially：Power information collection during Y Equipment failure rate is less than or equal to F%, confidence level 50%；Wherein Y >=0,0≤F≤100.

In the step 1-3, the failure mode is quantity of state collection, electric energy meter data acquisition, communication, analog measurement Failure under error and mains voltage variations；

(1) change all input states, test 5 times；If the quantity of state that test main frame shows is not inconsistent for 5 times with input state Close, be judged to quantity of state collection failure；

(2) test main frame copies and accepts electric energy meter data by power information collecting device, if it is aobvious to copy and accept failure or test main frame The electric energy meter data shown are inconsistent with electric energy meter data, are judged to electric energy meter data acquisition failure；

(3) number of communications should be greater than 10 times, occur and 10 equal communication failures of test main frame in functional test, be judged to communication Failure；

(4) test 5 times and average, measure the worst error value of the overproof regulation of voltage elementary error, be judged to analog quantity Measurement error fails；

(5) it is respectively U in supply voltage_n+ 20% and U_nWhen -20%, judge quantity of state collection, electric energy meter data acquisition, lead to If thering is one to fail in letter and analog measurement error, mains voltage variations failure is judged to；Wherein U_nIt is source nominal voltage.

The failure statistics principle includes：

(1) because of the failure that External Test Equipment influence or human factor cause, it is not counted in failure；

(2) there is the failure of multiple identical items in same test period in the test specimen of power information collecting device, Only record fails for the first time, and test period afterwards no longer carries out the project testing to this test specimen；

(3) test specimen occurs being unable to self-starting or self- recoverage in single test period, analyzes reason, test specimen weight Tested after newly manually starting；Such as the project testing does not fail, and corresponding failure mode is recorded as suspending item, this range estimation Examination is failed, then this is designated as expired entry；

(4) test specimen project testing in single test period does not fail, but the failure outside test event occurs, Analysis reason；If still without failure, corresponding failure mode is recorded as the project of the test specimen at the end of stress test Suspension item.

The step 2 is comprised the following steps：

Step 2-1：Determine proof stress and test specimen；

Step 2-2：Set up accelerated life model；

Step 2-3：Minimum test period and experiment termination time under identified sign level；

Step 2-4：Humiture stress accelerated life test is carried out, and carries out failure statistics.

The step 2-1 specifically includes following steps：

Step 2-1-1：Temperature and humidity is the environmental stress larger to power information collecting device reliability effect, is chosen Following level Four stress level is tested；

(1) temperature be 75 DEG C, and humidity be 95% when, be defined as first order stress level；

(2) temperature be 75 DEG C, and humidity be 85% when, be defined as second level stress level；

(3) temperature be 75 DEG C, and humidity be 75% when, be defined as third level stress level；

(4) temperature be 65 DEG C, and humidity be 95% when, be defined as fourth stage stress level；

Step 2-1-2：By exfactory inspection qualified same batch power information collection of the test agent from batch production Randomly selected in equipment, the sample number of each combined stress experiment is no less than 10.

Accelerated life model in the step 2-2 uses Peck models, for describe temperature and humidity combined stress with The relation in life-span；The accelerator coefficient AF of Peck models is expressed as：

Wherein, RH_uIt is the per cent relative humidity under regular service conditions, RH_sFor the percentage under stress level is relatively wet Degree；T_uIt is the temperature represented with k under regular service conditions, T_sIt is the temperature represented with k under stress level, k is that Boltzmann is normal Number, takes 8.617 × 10^-5eV/K；E_aIt is the activation energy represented with electron volts, span is 0.3~1.5；N joins for accelerator coefficient Number, span is 1~12.

In the step 2-3, make E_aRepresentative value 0.9 is taken, and n takes representative value 3, the AF obtained by formula (1) brings formula (2) into i.e. Can obtain the minimum test period D under every grade of stress level_min, it is expressed as：

Wherein, UCL₁To occur the 1st failure probability estimate of failure under 50% confidence level, by looking into IEC62059- 31-1 Appendix D is obtained, and c is additional Failure Factor, value 15；

Fixed time test is used under every grade of stress level, experiment in a case where terminates：

(1) minimum test period is not up to, but total Test sample fails has occurred；

(2) minimum test period has been reached, and has there are at least 5 test specimens and has lost in each independent failure mode Effect；

(3) if reaching minimum test period, the failure number of test specimen is less than 5, then continue to test until certain independently loses There are at least 5 test sample failures in effect pattern or test period has reached 2 times of minimum test periods.

In the step 2-4, humiture stress accelerated life test process is carried out as follows：

In every grade of process of the test of stress level, test specimen is in running order all the time；Temperature is applied to test specimen While degree, humidity combination stress, ac analog input applies rated voltage U_n, quantity of state input connection external analog Device, test main frame is connected by order wire with test specimen, but is not communicated；Test specimen starts in accelerated life test Before, failure mode is tested under normal assays room environmental, and its function and key property should meet the requirements；If test specimen is not Meet the requirements, give and replace, it is ensured that all test specimens are all certified products before experiment；

Every group of stress accelerated life test uses fixed time test, and minimum test period should according to every group of acceleration Accelerator coefficient and the terminal reliability requirement of power level determine that sample number r >=5 of being failed at the end of minimum test period are tested Can terminate, should otherwise extend test period；And during every group of stress level experiment, fail data statistics should be carried out.

The step 3 is comprised the following steps：

Step 3-1：Test data is sorted, and calculates failure sequence number and Median rank failure probability estimate；

Step 3-2：Calculate Weibull distribution parameters of all kinds of failure modes under stress levels at different levels；

Step 3-3：The accelerator coefficient of all kinds of failure modes；

Step 3-4：Calculate accelerator coefficient of all kinds of failure modes under stress levels at different levels；

Step 3-5：Calculate all kinds of failure modes Weibull distribution parameters in normal conditions of use；

Step 3-6：Calculate all kinds of failure modes cumulative failure probability in normal conditions of use and accumulation reliability.

In the step 3-1, suspension item is sorted from small to large with expired entry by failure accumulated time, failure sequence number is with Position order failure probability estimate is calculated by formula (3) and (4) respectively, is had：

Wherein, r_jIt is j-th adjusted failure sequence number, r_j-1It is upper one adjusted failure sequence number, N is should The expired entry and suspension item sum, i.e. test specimen sum of failure mode；It is Median rank failure probability estimate.

In the step 3-2, Weibull distribution parameters include form parameter β and scale parameter η, based on least square method meter Calculate form parameter β and scale parameter η process of all kinds of failure modes under stress levels at different levels as follows：

Weibull distribution is obeyed in the life-span distribution of power information collecting device, and cumulative failure probability represents have with F (t)：

Formula (5) both sides are taken into natural logrithm, is had：

Second natural logrithm is taken again, is had：

If y=ln (- ln (1-F (t))), A=- β ln (η), B=β, x=ln (t)；Then have：

Y=A+Bx (8)

Wherein, x_i=ln (TTF_i), TTF_iIt is the i-th cumulative failure time of test specimen failure；y_i=ln (- ln (1-F (TTF_i))), F (TTF_i) it is that, corresponding to i-th failure probability of test specimen failure, p is the failure number observed；

Form parameter β and scale parameter η can be obtained by A and B, had：

β=B (11)

In the step 3-3, the accelerator coefficient of all kinds of failure modes includes what is represented with electron volts under all kinds of failure modes Activation energy_a' and accelerator coefficient parameter n '；Calculating process is as follows：

Logarithm is asked to formula (1) both sides, is obtained：

MeetWhen,It is the accelerator coefficient under maximum stress level, andAF_iIt is the accelerator coefficient under i-stage stress level,It is the yardstick ginseng under maximum stress level Number, andη_iIt is the scale parameter under i-stage stress level；Have：

Wherein, RH_iIt is the humidity under i-stage stress level, RH_maxIt is the highest humidity of stress level, and has RH_max=RH₁ =RH₄；T_iIt is the temperature under i-stage stress level, T_maxIt is the maximum temperature of stress level, and has T_max=T₁=T₂=T₃；

Setting equation Z_i=nX_i+E_aY_i, equation coefficient X_i、Y_iAnd Z_iIt is expressed as：

(1) under first order stress level, X₁=Y₁=Z₁=0；

(2) under the stress level of the second level,

(3) under third level stress level,

(4) under fourth stage stress level,

Wherein, η₁、η₂、η₃And η₄Scale parameter under respectively first to fourth grade stress level；

Then the activation energy for being represented with electron volts under all kinds of failure modes_a' be expressed as with accelerator coefficient parameter n '：

In the step 3-4, according to the per cent relative humidity RH under regular service conditions_uWith under regular service conditions with The temperature T that k is represented_u, and the E for calculating_a' calculate accelerator coefficient of all kinds of failure modes under stress levels at different levels with n ' AF ', has：

In the step 3-5, all kinds of failure modes Weibull distribution parameters in normal conditions of use are joined including shape Number β ' and scale parameter η ', calculating process is as follows：

Weibull distribution is obeyed in the life-span distribution of power information collecting device, and all kinds of failure modes are in normal conditions of use The cumulative failure probability of power information collecting device represents have with F (t ')：

Formula (18) both sides are taken into natural logrithm, is had：

Second natural logrithm is taken again, is had：

If y '=ln (- ln (1-F (t '))), A '=- β ' ln (η '), B '=β ', x '=ln (t ')；Then have：

Y '=A '+B ' x ' (21)

Wherein, x_i'=ln (TTF_i'), TTF_i' under regular service conditions during the cumulative failure of i-th test specimen failure Between；

y_i'=ln (- ln (1-F (TTF_i'))), F (TTF_i') it is to be lost corresponding to i-th test specimen under regular service conditions The failure probability of effect, p is the failure number observed；

Form parameter β ' and scale parameter η ' can be obtained by A ' and B ', had：

β '=B ' (24)

In the step 3-6, by all kinds of failure modes form parameter β ' in normal conditions of use and scale parameter η ' Substitute into respectively in formula (5), obtain all kinds of failure modes cumulative failure probability F in normal conditions of use₁(t)、F₂(t)、F₃ (t)、F₄(t) and F₅(t)；All kinds of failure modes accumulation reliability in normal conditions of use is expressed as

R (t)=(1-F₁(t))(1-F₂(t))(1-F₃(t))(1-F₄(t))(1-F₅(t)) (26)

Wherein, R (t) is all kinds of failure modes accumulation reliability in normal conditions of use.

Compared with prior art, the beneficial effects of the present invention are：

1. the present invention instructs power information collecting device humiture to set up the reliability model of power information collecting device The development of stress accelerated life test, and from the fail data under acceleration environment derive regular service conditions under reliability The estimate of characteristic quantity, verifies whether the reliability of power information collecting device meets requirement；

2. power information collecting device reliability compliance test method is not only able to verify that power information collecting device specifies the longevity Order the reliability of point, and its complete period life curve can be obtained, for the operation and maintenance of power information collecting device provide according to According to；

3. the reliability demonstration of power information collecting device is realized, intuitively, is effectively detected for testing staff provides Analysis means, are conducive to finding the defect in power information collecting device conceptual design, component selection and manufacturing process control, Promote quality improvement；

4. technical basis are provided to carry out power information collecting device supplier evaluation, promote supplier to improve reliability and set Meter, so as to reduce power information collecting device operation troubles rate, extends service life；

5. the stability and reliability of power information collecting device are further increased, to accelerate propulsion power information collection Equipment and intelligent grid construction provide technical support.

Brief description of the drawings

Fig. 1 is the test method flow chart of power information collecting device reliability demonstration.

Specific embodiment

The present invention is described in further detail below in conjunction with the accompanying drawings.

As Fig. 1, the present invention provide a kind of test method of power information collecting device reliability demonstration, methods described includes Following steps：

Step 1：Power information collecting device reliability model is set up, failure mode, failure criteria and failure statistics are determined Principle；

Step 2：Power information collecting device humiture stress accelerated life test is carried out, and carries out failure statistics；

Step 3：The test data that accelerated life test is obtained is analyzed, and obtains cumulative failure probability and reliability Degree.

The step 1 is comprised the following steps：

Step 1-1：Set up power information collecting device reliability model；

Step 1-2：Determine power information collecting device reliability demonstration requirement；

Step 1-3：Determine failure criteria, failure mode and failure statistics principle.

In the step 1-1, power information collecting device includes power module, main control module, interface module, AC sampling Module, display module, communication module and security module；Power information collecting device reliability model is series model, uses telecommunications Any Module Fail in breath collecting device, power information collecting device occurs as soon as failure, the test specimen failed in experiment Do not repaired.

In the step 1-2, power information collecting device reliability demonstration index is specially：Power information collection during Y Equipment failure rate is less than or equal to F%, confidence level 50%；Wherein Y >=0,0≤F≤100.

In the step 1-3, the failure mode is quantity of state collection, electric energy meter data acquisition, communication, analog measurement Failure under error and mains voltage variations；

(1) change all input states, test 5 times；If the quantity of state that test main frame shows is not inconsistent for 5 times with input state Close, be judged to quantity of state collection failure；

(2) test main frame copies and accepts electric energy meter data by power information collecting device, if it is aobvious to copy and accept failure or test main frame The electric energy meter data shown are inconsistent with electric energy meter data, are judged to electric energy meter data acquisition failure；

(3) number of communications should be greater than 10 times, occur and 10 equal communication failures of test main frame in functional test, be judged to communication Failure；

(4) test 5 times and average, measure the worst error value of the overproof regulation of voltage elementary error, be judged to analog quantity Measurement error fails；

(5) it is respectively U in supply voltage_n+ 20% and U_nWhen -20%, judge quantity of state collection, electric energy meter data acquisition, lead to If thering is one to fail in letter and analog measurement error, mains voltage variations failure is judged to；Wherein U_nIt is source nominal voltage.

The failure statistics principle includes：

(1) because of the failure that External Test Equipment (main to include high/low temperature Alternate hot and humid case) influence or human factor causes, It is not counted in failure；

(2) there is the failure of multiple identical items in same test period in the test specimen of power information collecting device, Only record fails for the first time, and test period afterwards no longer carries out the project testing to this test specimen；

(3) test specimen occurs being unable to self-starting or self- recoverage in single test period, analyzes reason, test specimen weight Tested after newly manually starting；Such as the project testing does not fail, and corresponding failure mode is recorded as suspending item, this range estimation Examination is failed, then this is designated as expired entry；

(4) test specimen project testing in single test period does not fail, but the failure outside test event occurs, Analysis reason；If still without failure, corresponding failure mode is recorded as the project of the test specimen at the end of stress test Suspension item.

The step 2 is comprised the following steps：

Step 2-1：Determine proof stress and test specimen；

Step 2-2：Set up accelerated life model；

Step 2-3：Minimum test period and experiment termination time under identified sign level；

Step 2-4：Humiture stress accelerated life test is carried out, and carries out failure statistics.

The step 2-1 specifically includes following steps：

Step 2-1-1：Temperature and humidity is the environmental stress larger to power information collecting device reliability effect, is chosen Following level Four stress level is tested；

(1) temperature be 75 DEG C, and humidity be 95% when, be defined as first order stress level；

(2) temperature be 75 DEG C, and humidity be 85% when, be defined as second level stress level；

(3) temperature be 75 DEG C, and humidity be 75% when, be defined as third level stress level；

(5) temperature be 65 DEG C, and humidity be 95% when, be defined as fourth stage stress level；

Step 2-1-2：By exfactory inspection qualified same batch power information collection of the test agent from batch production Randomly selected in equipment, the sample number of each combined stress experiment is no less than 10.

Accelerated life model in the step 2-2 uses Peck models, for describe temperature and humidity combined stress with The relation in life-span；The accelerator coefficient AF of Peck models is expressed as：

Wherein, RH_uIt is the per cent relative humidity under regular service conditions, RH_sFor the percentage under stress level is relatively wet Degree；T_uIt is the temperature represented with k under regular service conditions, T_sIt is the temperature represented with k under stress level, k is that Boltzmann is normal Number, takes 8.617 × 10^-5eV/K；E_aIt is the activation energy represented with electron volts, span is 0.3~1.5；N joins for accelerator coefficient Number, span is 1~12.

In the step 2-3, make E_aRepresentative value 0.9 is taken, and n takes representative value 3, the AF obtained by formula (1) brings formula (2) into i.e. Can obtain the minimum test period D under every grade of stress level_min, it is expressed as：

Wherein, UCL₁To occur the 1st failure probability estimate of failure under 50% confidence level, by looking into IEC62059- 31-1 Appendix D is obtained, and c is additional Failure Factor, value 15；

Fixed time test is used under every grade of stress level, experiment in a case where terminates：

(1) minimum test period is not up to, but total Test sample fails has occurred；

(2) minimum test period has been reached, and has there are at least 5 test specimens and has lost in each independent failure mode Effect；

(3) if reaching minimum test period, the failure number of test specimen is less than 5, then continue to test until certain independently loses There are at least 5 test sample failures in effect pattern or test period has reached 2 times of minimum test periods.

In the step 2-4, humiture stress accelerated life test process is carried out as follows：

In every grade of process of the test of stress level, test specimen is in running order all the time；Temperature is applied to test specimen While degree, humidity combination stress, ac analog input applies rated voltage U_n, quantity of state input connection external analog Device, test main frame is connected by order wire with test specimen, but is not communicated；Test specimen starts in accelerated life test Before, failure mode is tested under normal assays room environmental, and its function and key property should meet the requirements；If test specimen is not Meet the requirements, give and replace, it is ensured that all test specimens are all certified products before experiment；

Every group of stress accelerated life test uses fixed time test, and minimum test period should according to every group of acceleration Accelerator coefficient and the terminal reliability requirement of power level determine that sample number r >=5 of being failed at the end of minimum test period are tested Can terminate, should otherwise extend test period；And during every group of stress level experiment, fail data statistics should be carried out.

The step 3 is comprised the following steps：

Step 3-1：Test data is sorted, and calculates failure sequence number and Median rank failure probability estimate；

Step 3-2：Calculate Weibull distribution parameters of all kinds of failure modes under stress levels at different levels；

Step 3-3：The accelerator coefficient of all kinds of failure modes；

Step 3-4：Calculate accelerator coefficient of all kinds of failure modes under stress levels at different levels；

Step 3-5：Calculate all kinds of failure modes Weibull distribution parameters in normal conditions of use；

Step 3-6：Calculate all kinds of failure modes cumulative failure probability in normal conditions of use and accumulation reliability.

In the step 3-1, suspension item is sorted from small to large with expired entry by failure accumulated time, failure sequence number is with Position order failure probability estimate is calculated by formula (3) and (4) respectively, is had：

Wherein, r_jIt is j-th adjusted failure sequence number, r_j-1It is upper one adjusted failure sequence number, N is should The expired entry and suspension item sum, i.e. test specimen sum of failure mode；It is Median rank failure probability estimate.

In the step 3-2, Weibull distribution parameters include form parameter β and scale parameter η, based on least square method meter Calculate form parameter β and scale parameter η process of all kinds of failure modes under stress levels at different levels as follows：

Weibull distribution is obeyed in the life-span distribution of power information collecting device, and cumulative failure probability represents have with F (t)：

Formula (5) both sides are taken into natural logrithm, is had：

Second natural logrithm is taken again, is had：

If y=ln (- ln (1-F (t))), A=- β ln (η), B=β, x=ln (t)；Then have：

Y=A+Bx (8)

Wherein, x_i=ln (TTF_i), TTF_iIt is the i-th cumulative failure time of test specimen failure；y_i=ln (- ln (1-F (TTF_i))), F (TTF_i) it is that, corresponding to i-th failure probability of test specimen failure, p is the failure number observed；

Form parameter β and scale parameter η can be obtained by A and B, had：

β=B (11)

In the step 3-3, the accelerator coefficient of all kinds of failure modes includes what is represented with electron volts under all kinds of failure modes Activation energy_a' and accelerator coefficient parameter n '；Calculating process is as follows：

Logarithm is asked to formula (1) both sides, is obtained：

MeetWhen,It is the accelerator coefficient under maximum stress level, andAF_iIt is the accelerator coefficient under i-stage stress level,It is the yardstick ginseng under maximum stress level Number, andη_iIt is the scale parameter under i-stage stress level；Have：

Wherein, RH_iIt is the humidity under i-stage stress level, RH_maxIt is the highest humidity of stress level, and has RH_max=RH₁ =RH₄；T_iIt is the temperature under i-stage stress level, T_maxIt is the maximum temperature of stress level, and has T_max=T₁=T₂=T₃；

Setting equation Z_i=nX_i+E_aY_i, equation coefficient X_i、Y_iAnd Z_iIt is expressed as：

(1) under first order stress level, X₁=Y₁=Z₁=0；

(2) under the stress level of the second level,

(3) under third level stress level,

(4) under fourth stage stress level,

Wherein, η₁、η₂、η₃And η₄Scale parameter under respectively first to fourth grade stress level；

Then the activation energy for being represented with electron volts under all kinds of failure modes_a' be expressed as with accelerator coefficient parameter n '：

In the step 3-4, according to the per cent relative humidity RH under regular service conditions_uWith under regular service conditions with The temperature T that k is represented_u, and the E for calculating_a' calculate accelerator coefficient of all kinds of failure modes under stress levels at different levels with n ' AF ', has：

In the step 3-5, all kinds of failure modes Weibull distribution parameters in normal conditions of use are joined including shape Number β ' and scale parameter η ', calculating process is as follows：

Weibull distribution is obeyed in the life-span distribution of power information collecting device, and all kinds of failure modes are in normal conditions of use The cumulative failure probability of power information collecting device represents have with F (t ')：

Formula (18) both sides are taken into natural logrithm, is had：

Second natural logrithm is taken again, is had：

If y '=ln (- ln (1-F (t '))), A '=- β ' ln (η '), B '=β ', x '=ln (t ')；Then have：

Y '=A '+B ' x ' (21)

Wherein, x_i'=ln (TTF_i'), TTF_i' under regular service conditions during the cumulative failure of i-th test specimen failure Between；

y_i'=ln (- ln (1-F (TTF_i'))), F (TTF_i') it is to be lost corresponding to i-th test specimen under regular service conditions The failure probability of effect, p is the failure number observed；

Form parameter β ' and scale parameter η ' can be obtained by A ' and B ', had：

β '=B ' (24)

In the step 3-6, by all kinds of failure modes form parameter β ' in normal conditions of use and scale parameter η ' Substitute into respectively in formula (5), obtain all kinds of failure modes cumulative failure probability F in normal conditions of use₁(t)、F₂(t)、F₃ (t)、F₄(t) and F₅(t)；All kinds of failure modes accumulation reliability in normal conditions of use is expressed as

R (t)=(1-F₁(t))(1-F₂(t))(1-F₃(t))(1-F₄(t))(1-F₅(t)) (26)

Wherein, R (t) is all kinds of failure modes accumulation reliability in normal conditions of use.

Finally it should be noted that：The above embodiments are merely illustrative of the technical solutions of the present invention rather than its limitations, institute The those of ordinary skill in category field specific embodiment of the invention can still be modified with reference to above-described embodiment or Equivalent, these are applying for this pending hair without departing from any modification of spirit and scope of the invention or equivalent Within bright claims.

Claims (14)

1. a kind of test method of power information collecting device reliability demonstration, it is characterised in that：Methods described includes following step Suddenly：

Step 1：Power information collecting device reliability model is set up, failure mode, failure criteria and failure statistics principle is determined；

Step 2：Power information collecting device humiture stress accelerated life test is carried out, and carries out failure statistics；

Step 3：The test data that accelerated life test is obtained is analyzed, and obtains cumulative failure probability and reliability；

The step 1 is comprised the following steps：

Step 1-1：Set up power information collecting device reliability model；

Step 1-2：Determine power information collecting device reliability demonstration requirement；

Step 1-3：Determine failure criteria, failure mode and failure statistics principle；

In the step 1-1, power information collecting device includes power module, main control module, interface module, AC sampling mould Block, display module, communication module and security module；Power information collecting device reliability model is series model, power information Any Module Fail in collecting device, power information collecting device occurs as soon as failure, and the test specimen failed in experiment is not Repaired；

In the step 1-2, power information collecting device reliability demonstration index is specially：Power information collecting device during Y Crash rate is less than or equal to F%, confidence level 50%；Wherein Y >=0,0≤F≤100；

In the step 1-3, the failure mode is quantity of state collection, electric energy meter data acquisition, communication, analog measurement error With the failure under mains voltage variations；

(1) change all input states, test 5 times；If the quantity of state that test main frame shows does not meet for 5 times with input state, It is judged to quantity of state collection failure；

(2) test main frame copies and accepts electric energy meter data by power information collecting device, if copying and accepting failure or test main frame shows Electric energy meter data are inconsistent with electric energy meter data, are judged to electric energy meter data acquisition failure；

(3) number of communications should be greater than 10 times, occur and 10 equal communication failures of test main frame in functional test, is judged to communication and loses Effect；

(4) test 5 times and average, measure the worst error value of the overproof regulation of voltage elementary error, be judged to analog measurement Error fails；

(5) it is respectively U in supply voltage_n+ 20% and U_nWhen -20%, judge quantity of state collection, electric energy meter data acquisition, communication and If thering is one to fail in analog measurement error, mains voltage variations failure is judged to；Wherein U_nIt is source nominal voltage.

2. the test method of power information collecting device reliability demonstration according to claim 1, it is characterised in that：It is described Failure statistics principle includes：

(1) because of the failure that External Test Equipment influence or human factor cause, it is not counted in failure；

(2) there is the failure of multiple identical items in same test period in the test specimen of power information collecting device, only remembers Record is failed for the first time, and test period afterwards no longer carries out the project testing to this test specimen；

(3) there is being unable to self-starting or self- recoverage in single test period in test specimen, analyzes reason, test specimen people again Work is tested after starting；Such as the project testing does not fail, and corresponding failure mode is recorded as suspending item, project testing hair Raw failure, then this is designated as expired entry；

(4) test specimen project testing in single test period does not fail, but the failure outside test event occurs, analysis Reason；If the project of the test specimen is still without failure at the end of stress test, corresponding failure mode is recorded as suspension .

3. the test method of power information collecting device reliability demonstration according to claim 1, it is characterised in that：It is described Step 2 is comprised the following steps：

Step 2-1：Determine proof stress and test specimen；

Step 2-2：Set up accelerated life model；

Step 2-3：Minimum test period and experiment termination time under identified sign level；

Step 2-4：Humiture stress accelerated life test is carried out, and carries out failure statistics.

4. the test method of power information collecting device reliability demonstration according to claim 3, it is characterised in that：It is described Step 2-1 specifically includes following steps：

Step 2-1-1：Temperature and humidity is the environmental stress larger to power information collecting device reliability effect, chooses following Level Four stress level is tested；

(1) temperature be 75 DEG C, and humidity be 95% when, be defined as first order stress level；

(2) temperature be 75 DEG C, and humidity be 85% when, be defined as second level stress level；

(3) temperature be 75 DEG C, and humidity be 75% when, be defined as third level stress level；

(4) temperature be 65 DEG C, and humidity be 95% when, be defined as fourth stage stress level；

Step 2-1-2：The test specimen sets from the same batch power information collection qualified by exfactory inspection of batch production Randomly selected in standby, the sample number of each combined stress experiment is no less than 10.

5. the test method of power information collecting device reliability demonstration according to claim 3, it is characterised in that：It is described Accelerated life model in step 2-2 uses Peck models, for describing the relation of temperature and humidity combined stress and life-span； The accelerator coefficient AF of Peck models is expressed as：

$AF={\left(\frac{{\mathrm{RH}}_u}{{\mathrm{RH}}_s}\right)}^{-n}{e}^{\frac{E_a}{k}(\frac{1}{T_u}-\frac{1}{T_s})}---\left(1\right)$

Wherein, RH_uIt is the per cent relative humidity under regular service conditions, RH_sIt is the per cent relative humidity under stress level； T_uIt is the temperature represented with k under regular service conditions, T_sIt is the temperature represented with k under stress level, k is Boltzmann constant, is taken 8.617×10^-5eV/K；E_aIt is the activation energy represented with electron volts, span is 0.3~1.5；N is accelerator coefficient parameter, is taken Value scope is 1~12.

6. the test method of power information collecting device reliability demonstration according to claim 5, it is characterised in that：It is described In step 2-3, make E_aTake representative value 0.9, and n takes representative value 3, the AF obtained by formula (1) bring into formula (2) can obtain every grade should Minimum test period D under power level_min, it is expressed as：

$D_{\min }=MAX(\frac{Y}{AF}{\[\frac{\ln (1-{\mathrm{UCL}}_1)}{\ln \left(1-\frac{cF}{1000}\right)}\]}^2,\frac{Y}{AF}{\[\frac{\ln (1-{\mathrm{UCL}}_1)}{\ln \left(1-\frac{cF}{1000}\right)}\]}^{\frac{1}{5}})---\left(2\right)$

Wherein, UCL₁To occur the 1st failure probability estimate of failure under 50% confidence level, by looking into IEC 62059-31-1 Appendix D is obtained, and c is additional Failure Factor, value 15；

Fixed time test is used under every grade of stress level, experiment in a case where terminates：

(1) minimum test period is not up to, but total Test sample fails has occurred；

(2) minimum test period has been reached, and has there are at least 5 test specimen failures in each independent failure mode；

(3) if reaching minimum test period, the failure number of test specimen is less than 5, then continue to test until certain independent failure mould There are at least 5 test sample failures in formula or test period has reached 2 times of minimum test periods.

7. the test method of power information collecting device reliability demonstration according to claim 3, it is characterised in that：It is described In step 2-4, humiture stress accelerated life test process is carried out as follows：

In every grade of process of the test of stress level, test specimen is in running order all the time；Temperature, wet is applied to test specimen While degree combined stress, ac analog input applies rated voltage U_n, quantity of state input connection external analog device, survey Examination main frame is connected by order wire with test specimen, but is not communicated；Test specimen before accelerated life test starts, just Often failure mode is tested under experiment room environmental, and its function and key property should meet the requirements；Will if test specimen does not meet Ask, give and replace, it is ensured that all test specimens are all certified products before experiment；

Every group of stress accelerated life test uses fixed time test, and minimum test period is according to every group of accelerated stress water Flat accelerator coefficient and terminal reliability requirement determine that sample number r >=5 of being failed at the end of minimum test period are tested Terminate, should otherwise extend test period；And when every group of stress level is tested, fail data statistics should be carried out.

8. the test method of power information collecting device reliability demonstration according to claim 5, it is characterised in that：It is described Step 3 is comprised the following steps：

Step 3-1：Test data is sorted, and calculates failure sequence number and Median rank failure probability estimate；

Step 3-2：Calculate Weibull distribution parameters of all kinds of failure modes under stress levels at different levels；

Step 3-3：The accelerator coefficient of all kinds of failure modes；

Step 3-4：Calculate accelerator coefficient of all kinds of failure modes under stress levels at different levels；

Step 3-5：Calculate all kinds of failure modes Weibull distribution parameters in normal conditions of use；

Step 3-6：Calculate all kinds of failure modes cumulative failure probability in normal conditions of use and accumulation reliability.

9. the test method of power information collecting device reliability demonstration according to claim 8, it is characterised in that：It is described In step 3-1, suspension item is sorted from small to large with expired entry by failure accumulated time, fail sequence number and Median rank failure probability Estimate is calculated by formula (3) and (4) respectively, is had：

$r_j=\frac{r_r\×r_{j-1}+(N+1)}{r_r+1}---\left(3\right)$

$F_{r_j}=\frac{(r_j-0.3)}{(N+0.4)}\%---\left(4\right)$

Wherein, r_jIt is j-th adjusted failure sequence number, r_j-1It is upper one adjusted failure sequence number, N is the failure mould The expired entry and suspension item sum, i.e. test specimen sum of formula；It is Median rank failure probability estimate.

10. the test method of power information collecting device reliability demonstration according to claim 8, it is characterised in that：Institute State in step 3-2, Weibull distribution parameters include form parameter β and scale parameter η, all kinds of failures are calculated based on least square method The form parameter β and scale parameter η processes under stress levels at different levels are as follows for pattern：

Weibull distribution is obeyed in the life-span distribution of power information collecting device, and cumulative failure probability represents have with F (t)：

$F\left(t\right)=1-e^{-{(t/\mathrm{\η})}^{\mathrm{\β}}}---\left(5\right)$

Formula (5) both sides are taken into natural logrithm, is had：

$-ln(1-F(t\left)\right)={\left(\frac{t}{\mathrm{\η}}\right)}^{\mathrm{\β}}---\left(6\right)$

Second natural logrithm is taken again, is had：

$ln(-ln(1-F\left(t\right)\left)\right)=\mathrm{\β}ln\left(\frac{t}{\mathrm{\η}}\right)=-\mathrm{\β}ln\left(\mathrm{\η}\right)+\mathrm{\β}ln\left(t\right)---\left(7\right)$

If y=ln (- ln (1-F (t))), A=- β ln (η), B=β, x=ln (t)；Then have：

Y=A+Bx (8)

$B=\frac{\underset{i=1}{\overset{p}{\Σ}}{x}_i{y}_i-\frac{\underset{i=1}{\overset{p}{\Σ}}{x}_i\underset{i=1}{\overset{p}{\Σ}}{y}_i}{p}}{\underset{i=1}{\overset{p}{\Σ}}{x_i}^2-\frac{{\left(\underset{i=1}{\overset{p}{\Σ}}{x}_i\right)}^2}{p}}---\left(9\right)$

$A=\frac{\underset{i=1}{\overset{p}{\Σ}}{y}_i}{p}-B\frac{\underset{i=1}{\overset{p}{\Σ}}{x}_i}{p}---\left(10\right)$

Wherein, x_i=ln (TTF_i), TTF_iIt is the i-th cumulative failure time of test specimen failure；y_i=ln (- ln (1-F (TTF_i))), F (TTF_i) it is that, corresponding to i-th failure probability of test specimen failure, p is the failure number observed；

Form parameter β and scale parameter η can be obtained by A and B, had：

β=B (11)

$\mathrm{\η}=e^{-\frac{A}{B}}---\left(12\right).$

The test method of 11. power information collecting device reliability demonstrations according to claim 8, it is characterised in that：Institute State in step 3-3, the accelerator coefficient of all kinds of failure modes includes the activation energy represented with electron volts under all kinds of failure modes_a' and Accelerator coefficient parameter n '；Calculating process is as follows：

Logarithm is asked to formula (1) both sides, is obtained：

$ln\left(AF\right)=-nln\left(\frac{{\mathrm{RH}}_u}{{\mathrm{RH}}_s}\right)+\frac{E_a}{k}(\frac{1}{T_u}-\frac{1}{T_s})---\left(13\right)$

MeetWhen,It is the accelerator coefficient under maximum stress level, andAF_iIt is the accelerator coefficient under i-stage stress level,It is the scale parameter under maximum stress level, Andη_iIt is the scale parameter under i-stage stress level；Have：

$\ln \left(\frac{{\mathrm{\η}}_i}{{\mathrm{\η}}_1}\right)=-n\ln \left(\frac{{\mathrm{RH}}_i}{{\mathrm{RH}}_{\max }}\right)+\frac{E_a}{k}(\frac{1}{T_i}-\frac{1}{T_{\max }})---\left(14\right)$

Wherein, RH_iIt is the humidity under i-stage stress level, RH_maxIt is the highest humidity of stress level, and has RH_max=RH₁= RH₄；T_iIt is the temperature under i-stage stress level, T_maxIt is the maximum temperature of stress level, and has T_max=T₁=T₂=T₃；

Setting equation Z_i=nX_i+E_aY_i, equation coefficient X_i、Y_iAnd Z_iIt is expressed as：

(1) under first order stress level, X₁=Y₁=Z₁=0；

(2) under the stress level of the second level,Y₂=0,

(3) under third level stress level,Y₃=0,

(4) under fourth stage stress level, X₄=0,

Wherein, η₁、η₂、η₃And η₄Scale parameter under respectively first to fourth grade stress level；

Then the activation energy for being represented with electron volts under all kinds of failure modes_a' be expressed as with accelerator coefficient parameter n '：

${E_a}^{\′}=\frac{\underset{i=1}{\overset{4}{\Σ}}{Y}_i{Z}_i\underset{i=1}{\overset{4}{\Σ}}{X_i}^2-\underset{i=1}{\overset{4}{\Σ}}{X}_i{Z}_i\underset{i=1}{\overset{4}{\Σ}}{X}_{i}Y}{{\left(\underset{i=1}{\overset{4}{\Σ}}{X}_i{Y}_i\right)}^2-\underset{i=1}{\overset{4}{\Σ}}{X_i}^2\underset{i=1}{\overset{4}{\Σ}}{Y_i}^2}---\left(15\right)$

$n^{\′}=\frac{\underset{i=1}{\overset{4}{\Σ}}{X}_i{Z}_i-{E_a}^{\′}\underset{i=1}{\overset{4}{\Σ}}{X}_i{Y}_i}{\underset{i=1}{\overset{4}{\Σ}}{X_i}^2}---\left(16\right).$

The test method of 12. power information collecting device reliability demonstrations according to claim 11, it is characterised in that：Institute In stating step 3-4, according to the per cent relative humidity RH under regular service conditions_uWith the temperature represented with k under regular service conditions Degree T_u, and the E for calculating_a' accelerator coefficient AF ' of all kinds of failure modes under stress levels at different levels is calculated with n ', have：

${\mathrm{AF}}^{\′}={\left(\frac{{\mathrm{RH}}_u}{{\mathrm{RH}}_s}\right)}^{-n^{\′}}{e}^{\frac{{E_a}^{\′}}{k}(\frac{1}{T_u}-\frac{1}{T_s})}---\left(17\right).$

The test method of 13. power information collecting device reliability demonstrations according to claim 10, it is characterised in that：Institute State in step 3-5, all kinds of failure modes Weibull distribution parameters in normal conditions of use include form parameter β ' and yardstick Parameter η ', calculating process is as follows：

Weibull distribution, the electricity consumption in normal conditions of use of all kinds of failure modes are obeyed in the life-span distribution of power information collecting device The cumulative failure probability of information collecting device represents have with F (t ')：

$F\left(t^{\′}\right)=1-e^{-{(t^{\′}/{\mathrm{\η}}^{\′})}^{{\mathrm{\β}}^{\′}}}---\left(18\right)$

Formula (18) both sides are taken into natural logrithm, is had：

$-ln(1-F(t^{\′}\left)\right)={\left(\frac{t^{\′}}{{\mathrm{\η}}^{\′}}\right)}^{{\mathrm{\β}}^{\′}}---\left(19\right)$

Second natural logrithm is taken again, is had：

$ln(-ln(1-F\left(t^{\′}\right)\left)\right)={\mathrm{\β}}^{\′}ln\left(\frac{t^{\′}}{{\mathrm{\η}}^{\′}}\right)=-{\mathrm{\β}}^{\′}ln\left({\mathrm{\η}}^{\′}\right)+{\mathrm{\β}}^{\′}ln\left(t^{\′}\right)---\left(20\right)$

If y '=ln (- ln (1-F (t '))), A '=- β ' ln (η '), B '=β ', x '=ln (t ')；Then have：

Y '=A '+B ' x ' (21)

$B^{\′}=\frac{\underset{i=1}{\overset{p}{\Σ}}{x_i}^{\′}{y_i}^{\′}\frac{\underset{i=1}{\overset{p}{\Σ}}{x_i}^{\′}\underset{i=1}{\overset{p}{\Σ}}{y_i}^{\′}}{p}}{\underset{i=1}{\overset{p}{\Σ}}{x_i}^{\′2}-\frac{{\left(\underset{i=1}{\overset{p}{\Σ}}{x_i}^{\′}\right)}^2}{p}}---\left(22\right)$

$A^{\′}=\frac{\underset{i=1}{\overset{p}{\Σ}}{y_i}^{\′}}{p}-B^{\′}\frac{\underset{i=1}{\overset{p}{\Σ}}{x_i}^{\′}}{p}---\left(23\right)$

Wherein, x_i'=ln (TTF_i'), TTF_i' it is the i-th cumulative failure time of test specimen failure under regular service conditions； y_i'=ln (- ln (1-F (TTF_i'))), F (TTF_i') it is corresponding to i-th failure of test specimen failure under regular service conditions Probability, p is the failure number observed；

Form parameter β ' and scale parameter η ' can be obtained by A ' and B ', had：

β '=B ' (24)

${\mathrm{\η}}^{\′}=e^{-\frac{A^{\′}}{B^{\′}}}---\left(25\right).$

The test method of 14. power information collecting device reliability demonstrations according to claim 13, it is characterised in that：Institute State in step 3-6, all kinds of failure modes form parameter β ' in normal conditions of use and scale parameter η ' are substituted into formula respectively (5) in, all kinds of failure modes cumulative failure probability F in normal conditions of use is obtained₁(t)、F₂(t)、F₃(t)、F₄(t) and F₅ (t)；All kinds of failure modes accumulation reliability in normal conditions of use is expressed as

R (t)=(1-F₁(t))(1-F₂(t))(1-F₃(t))(1-F₄(t))(1-F₅(t)) (26)

Wherein, R (t) is all kinds of failure modes accumulation reliability in normal conditions of use.