The content of the invention
A kind of check defence method and device of short-circuit of power transformer cumulative effect provided in an embodiment of the present invention, solves
The method for being specifically designed for the measurement of impact load electrical parameters at present has a monocycle rectangular window method for fast measuring, using the monocycle
Electric energy fast algorithm, the caused skill that cannot accurately calculate fundamental wave or voltage, electric current and active power numerical value in harmonic wave frequency range
Art problem.
A kind of check defence method of short-circuit of power transformer cumulative effect provided in an embodiment of the present invention, including:
According to the short of predetermined power transformer repeatedly short circuit cumulative effect current value and preset national regulations number of times
Road electric current tolerance value carries out results contrast, determines cumulative effect coefficient;
According to the short-circuit current value that the cumulative effect coefficient and preset Electromagnetic Simulation mode computation can be born;
According to the cumulative effect coefficient and possible short-circuit number of times, determine that transformer defends the short circuit current of cumulative effect
Ability.
Alternatively, according to the cumulative effect coefficient and possible short-circuit number of times, determine transformer defence cumulative effect
Also include after short circuit current ability:
According to the repeatedly short-circuit short-circuit number of times of the cumulative effect coefficient and the predetermined power transformer, it is determined that
Transformer defends the short circuit current ability of cumulative effect.
Alternatively, according to predetermined power transformer, repeatedly short circuit cumulative effect current value and preset national regulations are secondary
Several short circuit current tolerance values carry out results contrast, also include before determining cumulative effect coefficient:
The accumulative operation of multiple short circuit based on maximum short circuit current 60-70% is carried out to the power transformer, institute is determined
State cumulative effect current value.
Alternatively, the cumulative effect coefficient isWherein, I is single short-circuit current value,
Imax is tolerable short-circuit current value, and n is short circuit current number of times.
Alternatively, work as short circuit current<During 0.8pu, then the short-circuit number of times is disregarded.
Alternatively, when the cumulative effect coefficient is more than 4.5, then it is cumulative effect critical value.
Alternatively, the accumulative operation of multiple short circuit based on maximum short circuit current 60-70% is carried out to the power transformer,
Determine that the cumulative effect current value is specifically included:
The accumulative operation of multiple short circuit based on maximum short circuit current 60-70% is carried out to the power transformer;
When the multiple short circuit adds up operation, according to pre-set criteria short-circuit mode and reduction stream mode with impedance rate of change
Based on whether judge the accumulative operation of the multiple short circuit by short-circuit test, if, it is determined that the cumulative effect current value.
A kind of check defence installation of short-circuit of power transformer cumulative effect provided in an embodiment of the present invention, including:
First determining unit, for according to the multiple short circuit cumulative effect current value and preset of predetermined power transformer
The short circuit current tolerance value of national regulations number of times carries out results contrast, determines cumulative effect coefficient;
Computing unit, for the short circuit electricity that can be born according to the cumulative effect coefficient and preset Electromagnetic Simulation mode computation
Flow valuve;
Second determining unit, for according to the cumulative effect coefficient and possible short-circuit number of times, determining that transformer is defendd
The short circuit current ability of cumulative effect.
Alternatively, the check defence installation of short-circuit of power transformer cumulative effect also includes:
Repeatedly short circuit adds up operating unit, for carrying out the power transformer based on maximum short circuit current 60-70%
The accumulative operation of multiple short circuit, determine the cumulative effect current value.
3rd determining unit, for repeatedly short according to the cumulative effect coefficient and the predetermined power transformer
The short-circuit number of times on road, determines that transformer defends the short circuit current ability of cumulative effect.
Alternatively, repeatedly the accumulative operating unit of short circuit is specifically included:
Repeatedly short circuit is accumulative operates subelement, for carrying out the power transformer based on maximum short circuit current 60-
The 70% accumulative operation of multiple short circuit;
Judge determination subelement, for when the multiple short circuit adds up operation, according to pre-set criteria short-circuit mode and drop
Low stream mode judges the accumulative operation of the multiple short circuit based on impedance rate of change whether by short-circuit test, if so, then true
The fixed cumulative effect current value.
As can be seen from the above technical solutions, the embodiment of the present invention has advantages below:
A kind of check defence method and device of short-circuit of power transformer cumulative effect provided in an embodiment of the present invention, method
Including:According to the short circuit electricity of the multiple short circuit cumulative effect current value of predetermined power transformer and preset national regulations number of times
Stream tolerance value carries out results contrast, determines cumulative effect coefficient;According to cumulative effect coefficient and preset Electromagnetic Simulation mode computation
The short-circuit current value that can be born;According to cumulative effect coefficient and possible short-circuit number of times, transformer defence cumulative effect is determined
Short circuit current ability.In the present embodiment, by according to predetermined power transformer repeatedly short circuit cumulative effect current value and
The short circuit current tolerance value of preset national regulations number of times carries out results contrast, determines cumulative effect coefficient, according to cumulative effect system
The short-circuit current value that number and preset Electromagnetic Simulation mode computation can be born, according to cumulative effect coefficient and possible short-circuit number of times,
Determine that transformer defends the short circuit current ability of cumulative effect, solve and how can reflect that equipment tolerance cumulative effect itself resists
Short-circuit capacity difference, again can be with the short-circuit calculation and check of equipment accumulation that repeatedly short circuit is associated in operation of power networks life cycle
Method, meets the technical problem of the work requirements such as equipment dependability prediction, life prediction.
Specific embodiment
A kind of check defence method and device of short-circuit of power transformer cumulative effect provided in an embodiment of the present invention, solves
Equipment tolerance cumulative effect anti-short circuit capability difference itself how can be reflected, again can with operation of power networks life cycle in repeatedly
The short-circuit calculation and check method of equipment accumulation that short circuit is associated, meets the work such as equipment dependability prediction, life prediction
The technical problem of demand.
To enable goal of the invention of the invention, feature, advantage more obvious and understandable, below in conjunction with the present invention
Accompanying drawing in embodiment, is clearly and completely described to the technical scheme in the embodiment of the present invention, it is clear that disclosed below
Embodiment be only a part of embodiment of the invention, and not all embodiment.Based on the embodiment in the present invention, this area
All other embodiment that those of ordinary skill is obtained under the premise of creative work is not made, belongs to protection of the present invention
Scope.
Refer to Fig. 1, a kind of check defence method of short-circuit of power transformer cumulative effect provided in an embodiment of the present invention
One embodiment includes:
101st, the accumulative operation of multiple short circuit based on maximum short circuit current 60-70% is carried out to power transformer, it is determined that tired
Product effects current value;
When the check for needing short-circuit of power transformer cumulative effect is defendd, it is necessary first to which power transformer is based on
The accumulative operation of multiple short circuit of maximum short circuit current 60-70%, determines cumulative effect current value.
102nd, according to the multiple short circuit cumulative effect current value of predetermined power transformer and preset national regulations number of times
Short circuit current tolerance value carry out results contrast, determine cumulative effect coefficient;
When the accumulative operation of multiple short circuit based on maximum short circuit current 60-70% is carried out to power transformer, it is determined that accumulation
After effects current value, need according to the multiple short circuit cumulative effect current value of predetermined power transformer and preset GB rule
The short circuit current tolerance value for determining number of times carries out results contrast, determines cumulative effect coefficient.
103rd, the short-circuit current value that can be born according to cumulative effect coefficient and preset Electromagnetic Simulation mode computation;
When according to predetermined power transformer repeatedly short circuit cumulative effect current value and preset national regulations number of times
Short circuit current tolerance value carries out results contrast, after determining cumulative effect coefficient, needs according to cumulative effect coefficient and preset electricity
Magnetic simulation model calculates the short-circuit current value that can be born.
104th, according to cumulative effect coefficient and possible short-circuit number of times, determine that transformer defends the short circuit current of cumulative effect
Ability;
After the short-circuit current value that can be born according to cumulative effect coefficient and preset Electromagnetic Simulation mode computation, root is needed
According to cumulative effect coefficient and possible short-circuit number of times, determine that transformer defends the short circuit current ability of cumulative effect.
105th, according to the short-circuit number of times that cumulative effect coefficient and predetermined power transformer are repeatedly short-circuit, determine transformation
Device defends the short circuit current ability of cumulative effect.
When according to cumulative effect coefficient and possible short-circuit number of times, the short circuit current energy of transformer defence cumulative effect is determined
After power, need, according to the repeatedly short-circuit short-circuit number of times of cumulative effect coefficient and predetermined power transformer, to determine transformation
Device defends the short circuit current ability of cumulative effect.
In the present embodiment, cumulative effect coefficient isWherein, I is single short-circuit current value,
Imax is tolerable short-circuit current value, and n is short circuit current number of times, works as short circuit current<During 0.8pu, then short-circuit number of times is disregarded, when tired
When product effect coefficient is more than 4.5, then it is cumulative effect critical value.
It is described with a concrete application scene below, as shown in figure 3, application examples includes:According to GB GB1094.5 electricity
Power transformer bears short-circuit capacity, and in testing standard, the every phase study number of times of regulation 3 times, are tested by 100% short-circuit current value, at present
All of short-circuit test is carried out by this standard.Engineering practice is that, in the whole transformer life cycle, short-circuit number of times may
More than 3 times, short circuit current but not necessarily reaches 100% every time, and transformer can bear how much current how many times, it is also possible to by grinding
Verifying, the multiple accumulation test for reducing electric current may be referred to the meter of GB1094.5 annex to the short-circuit test of the reduction electric current of the property studied carefully
Calculation method is estimated in advance, it is determined that the maximum short circuit current that can be born, then open by maximum short circuit current 60-70% can be born
Beginning short circuit accumulation test.
The test method of standard short-circuit test method and reduction stream, two kinds of tests are all by GB1094.5 standards
4.2.7 fault detect and the judgement of result of the test, is that foundation judges whether jointly with the test of other retrials with impedance rate of change
By short-circuit test.
The multiple accumulation short-circuit test of the short-circuit test and reduction short circuit current of standard, all should obtain model electricity as far as possible
The tolerance short circuit current critical value and the tolerance current critical value of multiple accumulation short-circuit test of power transformer.This is a kind of using real
The method that survey mode obtains cumulative effect coefficient.
According to the short circuit current tolerance of the multiple short circuit cumulative effect current value of above power transformer and national regulations number of times
Value carries out results contrast, determines cumulative effect coefficient, cumulative effect coefficientIn formula:I- singles
Short-circuit current value, Imax- can tolerate short-circuit current value;N- short circuit current number of times.Work as short circuit current<During 0.8pu, not metering number.
The short-circuit current value that can be born is calculated according to cumulative effect coefficient and electromagnetic simulation software, the model transformation is checked
The multiple accumulation short-circuit current value that device can bear, according to test experience, works as k>When 4.5, it is believed that be cumulative effect critical value.
According to cumulative effect coefficient and possible short-circuit number of times, determine that transformer defends the short circuit current energy of cumulative effect
Power.
In the present embodiment, by according to the multiple short circuit cumulative effect current value of predetermined power transformer and preset state
The short circuit current tolerance value of mark stipulated number carries out results contrast, determines cumulative effect coefficient, according to cumulative effect coefficient and in advance
The short-circuit current value that Electromagnetic Simulation mode computation can be born is put, according to cumulative effect coefficient and possible short-circuit number of times, it is determined that becoming
Depressor defends the short circuit current ability of cumulative effect, solves and how can reflect equipment tolerance cumulative effect resistance to shorting energy itself
Power difference, can accumulate short-circuit calculation and check method with the equipment that repeatedly short circuit is associated in operation of power networks life cycle again,
To meet the technical problem of the work requirements such as equipment dependability prediction, life prediction.
Refer to Fig. 2, a kind of check defence installation of short-circuit of power transformer cumulative effect provided in an embodiment of the present invention
Embodiment include:
Repeatedly short circuit adds up operating unit 201, for carrying out power transformer based on maximum short circuit current 60-70%'s
Repeatedly the accumulative operation of short circuit, determines cumulative effect current value.
Repeatedly the accumulative operating unit 201 of short circuit is specifically included:
Repeatedly short circuit is accumulative operates subelement 2011, for carrying out power transformer based on maximum short circuit current 60-
The 70% accumulative operation of multiple short circuit;
Judge determination subelement 2012, in the accumulative operation of repeatedly short circuit, according to pre-set criteria short-circuit mode and drop
Low stream mode judges the accumulative operation of repeatedly short circuit based on impedance rate of change whether by short-circuit test, if, it is determined that it is tired
Product effects current value.
First determining unit 202, for according to predetermined power transformer repeatedly short circuit cumulative effect current value and
The short circuit current tolerance value of preset national regulations number of times carries out results contrast, determines cumulative effect coefficient;
Computing unit 203, for the short circuit electricity that can be born according to cumulative effect coefficient and preset Electromagnetic Simulation mode computation
Flow valuve;
Second determining unit 204, it is tired for according to cumulative effect coefficient and possible short-circuit number of times, determining transformer defence
The short circuit current ability of product effect.
3rd determining unit 205, for according to the repeatedly short circuit of cumulative effect coefficient and predetermined power transformer
Short-circuit number of times, determines that transformer defends the short circuit current ability of cumulative effect.
In the present embodiment, by the first determining unit 202, according to predetermined power transformer, repeatedly short circuit accumulation is imitated
The short circuit current tolerance value of induced current value and preset national regulations number of times carries out results contrast, determines cumulative effect coefficient, calculates
The short-circuit current value that unit 203 can be born according to cumulative effect coefficient and preset Electromagnetic Simulation mode computation, the second determining unit
204 according to cumulative effect coefficient and possible short-circuit number of times, determines that transformer defends the short circuit current ability of cumulative effect, solves
Equipment tolerance cumulative effect anti-short circuit capability difference itself how can be reflected, again can with operation of power networks life cycle in repeatedly
The short-circuit calculation and check method of equipment accumulation that short circuit is associated, meets the work such as equipment dependability prediction, life prediction
The technical problem of demand.
The above, above example only to illustrate technical scheme, rather than a limitation;Although with reference to front
State embodiment to be described in detail the present invention, it will be understood by those within the art that:Which still can be to front
State the technical scheme described in each embodiment to modify, or equivalent is carried out to which part technical characteristic;And these
Modification is replaced, and does not make the essence of appropriate technical solution depart from the spirit and scope of various embodiments of the present invention technical scheme.