CN108089106A - A kind of dichotomy test method of voltage dip tolerance - Google Patents
A kind of dichotomy test method of voltage dip tolerance Download PDFInfo
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- CN108089106A CN108089106A CN201711374527.0A CN201711374527A CN108089106A CN 108089106 A CN108089106 A CN 108089106A CN 201711374527 A CN201711374527 A CN 201711374527A CN 108089106 A CN108089106 A CN 108089106A
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- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
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- G01R31/12—Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing
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Abstract
The present invention discloses a kind of dichotomy test method of voltage dip tolerance, first determines a voltage dip amplitude, fault condition of the test equipment under the amplitude under maximum duration case：If the equipment not failure under maximum duration case assert that the equipment is resistant to the voltage dip of this amplitude, stops test；If the equipment fault under maximum duration case, minimum duration point device is normal, then next test time is the intermediate value of maximum duration and minimum duration；And so on, next test time is the intermediate value of this test time of measurement equipment and the test time of last different conditions, untilT n WithT n+1 Difference is no more than 5ms.The method of the present invention makes the test of equipment voltage dip tolerance more accurate, and while accuracy is ensured, greatly reduces workload needed for test, and then saves the testing time, ensures that test is accurately and quickly completed.
Description
Technical field
The present invention relates to two points of voltage drop tolerance technical field of measurement and test, specially a kind of voltage dip tolerance
Method test method.
Background technology
Electrification is referred to as 20th century greatest engineering achievement, and it is artificial net most complicated in the world that power grid, which is also referred to as,
Network is having been considered to the fundamental prerequisite of life at present.Power quality of today generally all meets ordinary consumption
The demand of person, but still great change may occur because of the difference in time or area, which results in voltage interruption or
Person's electric voltage exception can occur often, although being also to receive such case in some local people.However, current highly developed
Industry and digital economy era, production process have power quality higher requirement.These customer requirements have higher electric energy
Quality and the supply of more reliable electric energy, they want to reduce voltage interruption and other electrical energy power quality disturbances.But even if
In nowadays the most highly developed electric system, electrical energy power quality disturbance still happens occasionally, these electrical energy power quality disturbances pair
It is significantly affected in certain user.There is voltage interruptions, voltage dip, voltage swell, overvoltage, humorous for modern power systems
The problems such as ripple, flickering and other many power quality events and disturbance.
Today's society power quality problem the most significant is exactly voltage dip, and voltage dip has high-tech industry very big
Influence because when it is subjected to voltage dip, correlated process control system may be interrupted, so as to cause the huge damage of user
It loses.The research of American Electric Power research association, which shows that single-phase voltage temporarily drops, can cause the thousands of economic loss of manufacturer.It is connected to
The power electronic equipment of power grid has different degrees of voltage sag sensitivity.The susceptibility of equipment is mainly by two principal elements
It determines：The design of equipment and the physical characteristic of voltage dip.So need the accurate voltage tolerance test of set of system
Method.
According to《IEEE STD 1668-2014》Standard, it includes tested from top to bottom, from left to right with closed three kinds
Method, but its defined test plan is less slightly, can not meet the requirement accurately tested；Even add test plan and people
It is selected, to the promotion very little of test result accuracy.It is then to fixed several points that test method is recommended by C4.110 working groups
It is tested, however it remains the problem of accuracy is inadequate.In addition there is scholar to propose the method progressively tested, amplitude since 0V with
1% step-length increases, and the time tests since 0ms, and such test method show that test result is more accurate, but its workload
It is too big, because many unnecessary test points can omit.
《IEEE STD 1668-2014》It is as follows given the example parameter of test plan in standard：
A) maximum voltage amplitude：85% nominal value；
B) minimum voltage amplitude：0% standard value；
C) the maximum duration：2s；
D) minimum duration：0.02s；
E) amplitude step-length：5% nominal value (18 step)；
F) duration predetermined value：2s, 1s, 0.5s, 0.2s, 0.1s, 0.05s and 0.02s (seven Xun Huans).
1)《IEEE STD 1668-2014》Test method from top to bottom：This voltage dip test method is to maintain voltage
Temporarily the drop time is constant, and voltage dip amplitude changes from the maximum (being provided in test plan) of setting to minimum value (also as tested
Provide in the works), until voltage dip amplitude breaks down to minimum value or Device under test.Hereafter, when voltage dip continues
Between be reduced to next predetermined value, voltage dip amplitude repeats above-mentioned way.Temporary drop in voltage dip duration cycles
Amplitude declines, and has all been surveyed until all default duration.Its flow chart is as shown in Figure 1.
Method can not correctly test the voltage tolerance of such as A.C. contactor from top to bottom, be risen in 0 ° of voltage dip
During initial point, A.C. contactor is more preferable in the low voltage dip tolerance of amplitude.According to test method from top to bottom,
Test result is just the tolerance in the case of amplitude, it is impossible to which correct response goes out in 0 ° of voltage dip starting point, exchange
Contactor is more preferable in the low voltage dip tolerance of amplitude.
2)《IEEE STD 1668-2014》From left to right test method：This voltage dip test method is to maintain voltage
Temporary decline is constant, and the voltage dip duration changes (also such as from the minimum value (being provided in test plan) of setting to maximum
Provided in test plan), it breaks down until the voltage dip duration to maximum or Device under test.Hereafter, voltage is temporary
Range of decrease value is reduced to next predetermined value, and the duration repeats above-mentioned way.Duration in voltage dip amplitude Xun Huan
Become larger, until all default amplitudes have all been surveyed.Its flow chart is as shown in Figure 2.
From left to right test method there is test result it is inaccurate the problem of, this is because the time point in test plan
Very little, even if can add testing time point or reduce amplitude step-length, that is also artificially to add, and so not only improves work
Amount, and it is little to the promotion of test result accuracy.
3)《IEEE STD 1668-2014》Closed test method：This voltage dip test method is to find first
The trip time of minimum amplitude in test plan, after this initial trip-point is determined, using new Test Strategy.Wherein
One test point is in amplitude maximum in the works and maximum duration point, and then same method from top to bottom is the same, temporarily
The duration of drop remains unchanged, and amplitude is gradually reduced.Once it is determined that trip-point, then the duration be reduced in test plan
Next setting value, and the amplitude for testing amplitude selection trip-point increases a step-length and test plan maximum amplitude is larger
One.Test process continues, and to the last all setting values test in duration cycles is completed.Its flow chart such as Fig. 3 institutes
Show.
Closed test method can reduce workload, but similar with above method, still because the selection of test plan
And cause test result accuracy little.
4) progressive test method：This voltage dip test method is since 0V (test plan amplitude is minimum), keeps width
It is worth constant, the voltage dip duration changes from the minimum value (being provided in test plan) of setting to maximum (also such as tester
Regulation in drawing), but its step-length is 5ms, is broken down until the voltage dip duration to maximum or Device under test.This
Afterwards, voltage dip amplitude increases to next test point with 1% step-length, and the duration repeats way above.In temporary decline
Duration in cycling becomes larger, and until all default amplitudes have all been surveyed, flow chart is as shown in Figure 4.
The test method progressively tested refers to scrupulously test length by length according to step-length as its name suggests, and step-length obtains
Small, this precision of method is just very high, but its step-length obtains small workload and will greatly promote, and is unfavorable for the survey of multiple equipment
Amount.
5) test method is recommended by C4.110 working groups：Voltage sag immunity test grade and the SEMI F47- of recommendation
Test grade in 0706 is similar.However, the most long test voltage duration increased, this is to be able to preferably reflect
The shallow voltage dip that longer circuit breaker failure checkout time generates under distribution voltage levels is influenced caused by equipment.The method
Several fixed test points is recommended to be tested, the test point of recommendation is as shown in table 1 below：
1 voltage dip of table recommends test point
C4.110 working groups recommend test method workload to fix and very low, because it only secures three test points
It is tested, it is worst that this also results in its accuracy, is only capable of drawing substantially result.
According to test plan, each method full test number such as table 2：
2 each test method full test number of table
| Test method | From top to bottom | From left to right | It is closed | Progressively test | C4.110 recommends |
| Full test number | 126 | 126 | 126 | 34000 | 3 |
The content of the invention
In view of the above-mentioned problems, it is an object of the invention to propose that one kind can more accurately find equipment to be subjected to voltage dip
Trip time, and test job amount can be substantially reduced, accurately and quickly complete the measurement of equipment voltage dip tolerance
The dichotomy test method of voltage dip tolerance.Technical solution is as follows：
A kind of dichotomy test method of voltage dip tolerance, including：
Determine a voltage dip amplitude, test equipment maximum duration T under the amplitudemaxIn the case of failure feelings
Condition：
If in maximum duration TmaxIn the case of equipment not failure, then assert that the equipment is resistant to the voltage dip of this amplitude,
Stop test；
If in maximum duration TmaxIn the case of equipment fault, then next test time beTminFor minimum duration, T is setmin=0s, and equipment not failure under the duration；
If in duration T1In the case of equipment fault, then its situation and time TminShi Butong, then next test is held
The continuous time isIf in time T1In the case of equipment not failure, then its situation and time TmaxShi Butong, it is next
A test time is
And so on, next test time is this test time of measurement equipment and last different conditions
Test time intermediate value, until TnWith Tn+1Difference is no more than 5ms.
Further, the maximum duration Tmax=2s, voltage dip amplitude step-length are 2%.
The beneficial effects of the invention are as follows：The method of the present invention makes the test of equipment voltage dip tolerance more accurate, and
And while accuracy is ensured, workload needed for test is greatly reduced, and then saves the testing time, ensures that test is accurate quick
It completes on ground.
Description of the drawings
Fig. 1 is test method flow chart from top to bottom.
Fig. 2 is from left to right test method flow chart.
Fig. 3 is closed test method flow chart.
Fig. 4 is progressive test method flow chart.
Fig. 5 is dichotomy test method flow chart of the present invention.
Fig. 6 is test point schematic diagram of the present invention.
Fig. 7 is test method results figure from top to bottom.
Fig. 8 is test method results figure from left to right.
Fig. 9 is closed test method results figure.
Figure 10 is progressive test method test method results figure.
Figure 11 is C4.110 test method results figures.
Figure 12 is test method results figure of the present invention.
Figure 13 is test flow chart of the present invention.
Figure 14 is test circuit figure of the present invention.
Specific embodiment
The present invention is described in further details in the following with reference to the drawings and specific embodiments.The present embodiment continues to use IEEE
Partial test plan in 1668 standards, such as continue to use its full test time (2s), amplitude variation (0-85%).By letter
After single initial testing, minimum time is set as 0s, this is in order to which some especially sensitive equipment are included.
The amplitude step-length of the present embodiment setting 2%, because step-length too conference reduces measuring accuracy, step-length is too small then can be significantly
Increase workload.And keep voltage dip amplitude constant, voltage dip testing time point is determined based on dichotomy, first to electricity
Pressure temporarily tested by drop duration minimum value and maximum, and equipment trip condition is different under two duration cases, next
A duration is then the intermediate value of the two times, next one test time is this Median Time unit trip situation
With the intermediate value of the duration of a upper different situations, and so on, until the two neighboring testing time difference be no more than 5ms.
If equipment does not still trip in the maximum duration, then it is considered that this equipment can be resistant to the voltage dip of this amplitude.
Method And Principle and specific steps is described in detail below：
Mathematically, for successive and f (a) × f (b) on section [a, b]<0 function y=f (x), by continuous
Ground is divided into two the section where the zero point of function f (x), makes two endpoint Step wise approximation zero points in section, and then obtains zero
The method of point approximation is dichotomy.Based on this principle, in this test, equipment critical trip point can be regarded as zero point,
In the minimum testing time and full test time this section, continuous two points, critical trip point is eventually found.
Flow chart is as shown in figure 5, be as follows：
1. determining an amplitude, test equipment is in maximum duration TmaxIn the case of fault condition because minimum continue
Time TminFor 0s, so will not failure；If in maximum duration TmaxIn the case of equipment not failure, according to IEEE 1668
Standard can consider that equipment voltage tolerance is very strong, stop test.
2. if maximum duration TmaxIn the case of equipment fault, then next duration test point
3. if time T1In the case of equipment fault, then its situation and time TminShi Butong, next duration test
It puts and isIf time T1In the case of equipment not failure, then its situation and time TmaxShi Butong, it is next lasting
Time test point is
4. and so on, until TnWith Tn+1Difference is no more than 5ms.
The PLC (Programmable Logic Controller, programmable logic controller (PLC)) for choosing an Omron is surveyed
Try its tolerance to voltage dip.It is tested using 6 kinds of methods and the present embodiment method in background technology, comparison is commented
Estimate each method quality.
Fig. 7 is test method results figure from top to bottom；Fig. 8 is test method results figure from left to right；Fig. 9 is closed survey
Method for testing result figure；Figure 10 is progressive test method test method results figure；Figure 11 is C4.110 test method results figures；Figure 12 is
Dichotomy test method results figure in the present embodiment.
It can be seen that three kinds of method test results inside IEEE1668 standards are the same from more than test result, this is because
PLC is a kind of more accurate electronic equipment, in this test its voltage dip tolerance of Omron PLC used 145 ±
5ms.Since test plan is very few in IEEE1668 standards, obtain a result as 200ms, even increasing test plan, also pin
To this equipment, for other equipment, its voltage tolerance is different, then is no longer applicable in.In this test, IEEE1668 standards
In three kinds of method test result errors reached 50ms, it is evident that for this precision equipments of PLC, test result obviously cannot
It meets the requirements.C4.110 recommends test method because test point is very little, and curve shape all can not be provided clearly.And compare two points
Method and progressive test method, test result is very close, and measuring accuracy is also higher.Comparison tests this using distinct methods below
The test job amount of PLC such as table 3：
Table 3 tests the workload and accuracy of this PLC using distinct methods
| Test method | From top to bottom | From left to right | It is closed | Progressively test | Dichotomy | C4.110 |
| Workload | About 70 times | About 80 times | About 30 times | About 2500 times | About 450 times | 3 times |
| Error | 50ms | 50ms | 50ms | 5ms | 5ms | \ |
| Amplitude error | 4% | 4% | 4% | <1% | <1% | \ |
Workload is compared, although 3 kinds of method workloads of IEEE1668 standards are few, its error is larger, right
It is definitely unacceptable in this high precision apparatus of PLC；C4.110 can not then be suitable for this equipment；Progressively test method is accurate
Although degree is higher, its test job amount is too big, about 5 times of dichotomy.So the present invention can be in accuracy and workload
Aspect meet testing requirement, obtain accurate test result and save the testing time.
Claims (2)
1. a kind of dichotomy test method of voltage dip tolerance, which is characterized in that including：
Determine a voltage dip amplitude, test equipment maximum duration T under the amplitudemaxIn the case of fault condition：
If in maximum duration TmaxIn the case of equipment not failure, then assert that the equipment is resistant to the voltage dip of this amplitude, stop
Test；
If in maximum duration TmaxIn the case of equipment fault, then next test time beTmin
For minimum duration, T is setmin=0s, equipment not failure under the duration；
If in duration T1In the case of equipment fault, then its situation and time TminShi Butong, then when next test continues
Between beIf in time T1In the case of equipment not failure, then its situation and time TmaxShi Butong, next survey
Examination the duration be
And so on, next test time is the survey of this test time of measurement equipment and last different conditions
The intermediate value of duration is tried, until TnWith Tn+1Difference is no more than 5ms.
2. the dichotomy test method of voltage dip tolerance according to claim 1, which is characterized in that the maximum
Duration Tmax=2s, the minimum duration Tmin=0s, voltage dip amplitude step-length are 2%.
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| CN110542812A (en) * | 2019-08-30 | 2019-12-06 | 广州供电局有限公司 | Voltage sag immunity testing method, device, equipment and storage medium |
| CN110568325A (en) * | 2019-08-20 | 2019-12-13 | 广州供电局有限公司 | voltage sag tolerance capability detection method and device of speed-adjustable driving equipment |
| CN110632543A (en) * | 2019-09-26 | 2019-12-31 | 上海金智晟东电力科技有限公司 | Fault indicator performance index precision testing method and device and storage medium |
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| CN111781459A (en) * | 2020-07-30 | 2020-10-16 | 海南电网有限责任公司电力科学研究院 | Partial dichotomy test method for voltage sag tolerance capability |
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN109270446A (en) * | 2018-09-12 | 2019-01-25 | 四川大学 | A kind of Auto-Test System and method of A.C. contactor voltage tolerance |
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| CN110275076A (en) * | 2019-06-26 | 2019-09-24 | 广州供电局有限公司 | The immune degree test method of equipment voltage dip, device, computer equipment and medium |
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| CN110568325A (en) * | 2019-08-20 | 2019-12-13 | 广州供电局有限公司 | voltage sag tolerance capability detection method and device of speed-adjustable driving equipment |
| CN110542812A (en) * | 2019-08-30 | 2019-12-06 | 广州供电局有限公司 | Voltage sag immunity testing method, device, equipment and storage medium |
| CN110632543A (en) * | 2019-09-26 | 2019-12-31 | 上海金智晟东电力科技有限公司 | Fault indicator performance index precision testing method and device and storage medium |
| CN111162963A (en) * | 2019-12-11 | 2020-05-15 | 中国电力科学研究院有限公司 | Method and system for testing performance of network communication equipment based on binary iteration method |
| CN111781459A (en) * | 2020-07-30 | 2020-10-16 | 海南电网有限责任公司电力科学研究院 | Partial dichotomy test method for voltage sag tolerance capability |
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