CN106646306A - Converter transformer load loss field measurement result correction method - Google Patents
Converter transformer load loss field measurement result correction method Download PDFInfo
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- 238000012360 testing method Methods 0.000 claims abstract description 11
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R35/00—Testing or calibrating of apparatus covered by the other groups of this subclass
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Abstract
The invention discloses a converter transformer load loss field measurement result correction method comprising the steps that load testing is performed on a converter transformer before leaving the factory so that a harmonic loss model is obtained; load testing is performed after leaving the factory so that harmonic current waveforms are obtained; Fourier analysis is performed on the harmonic current waveforms so that the current effective value under each harmonic frequency is obtained; the load loss of the converter transformer under each harmonic frequency is obtained according to the harmonic loss model of the converter transformer and the current effective value under each harmonic frequency; and whether the iron core of the converter transformer deforms is judged according to the difference of the load loss of the converter transformer under each harmonic frequency and the measured load loss of the converter transformer. The method has the following advantages that the load loss measurement structure of the converter transformer can be corrected and the factory measurement data and the field measurement data are enabled to have comparability so that the situation of the iron core of the converter transformer can be judged and the quality of the iron core of the converter transformer can be given from the aspect of the loss measurement result.
Description
Technical field
Patent of the present invention is related to fields of measurement, and in particular to a kind of school of converter power transformer load loss situ measurements
Correction method.
Background technology
With the development of extra-high voltage direct-current transmission, electric pressure and capacity are being improved, in converter power transformer running
Harmonic wave and stray field are also being continuously increased, and its harmonic loss problem increasingly receives publicity.
For the excessive problem of large-sized converter transformer cost of transportation, for energy saving, State Grid Corporation of China proposes
The requirement of " Assembling, field test ".Due to the restriction of testing ground condition, there is larger harmonic wave and electromagnetic interference, to damaging
Consumption measurement generates certain impact, it is therefore desirable to which the influence factor of situ measurements is analyzed and is calculated.
Further, since large-sized converter transformer will carry out the measurement of open circuit loss and load loss before dispatching from the factory, then
Through long-distance transport, reach the spot and assembled.After assembling is completed, need to measure loss again, to judge in transportation
Whether middle iron core deforms upon even loss.But, because scene has larger harmonic wave interference, can cause its open circuit loss and
The change of load loss measured value, cause to be difficult to differentiate between judging be in situ measurements caused due to harmonic wave or due to iron
Heart becomes what is caused.
The content of the invention
It is contemplated that at least solving one of above-mentioned technical problem.
For this purpose, it is an object of the invention to proposing a kind of correction side of converter power transformer load loss situ measurements
Method so that factory's measurement data can have comparativity with field measurement data, so as to judge the situation of converter power transformer iron core.
To achieve these goals, embodiment of the invention discloses that a kind of converter power transformer load loss in-site measurement knot
The bearing calibration of fruit, comprises the following steps：S1：Load test is carried out to converter power transformer before dispatching from the factory, the change of current is obtained and is become
The harmonic loss model of depressor；S2：Load test is carried out after dispatching from the factory, harmonic current waveforms are obtained；S3：To the harmonic current
Waveform carries out Fourier analysis, obtains the current effective value under each harmonic frequency；S4：Damaged according to the harmonic wave of the converter power transformer
Current effective value under consumption model and each harmonic frequency obtains the load of the converter power transformer under each harmonic frequency and damages
Consumption；S5：Judge the load loss and the change of current transformation obtained by measurement of the converter power transformer under each harmonic frequency
Whether in preset range, the iron core of the converter power transformer does not have the difference of the load loss of device if in the preset range
Deform upon, the iron core of the converter power transformer is deformed upon if beyond the preset range.
The bearing calibration of converter power transformer load loss situ measurements according to embodiments of the present invention, can correct and change
The load loss measurement structure of convertor transformer so that factory's measurement data can have comparativity with field measurement data, so as to
Judge the situation of converter power transformer iron core, converter power transformer iron core quality is also given from loss measurement result.
In addition, the bearing calibration of converter power transformer load loss situ measurements according to the above embodiment of the present invention,
There can also be following additional technical characteristic：
Further, the harmonic loss model of the converter power transformer includes harmonic wave equivalent circuit, the harmonic wave equivalent electric
Road includes current source, equiva lent impedance, secondary side harmonic wave equivalent reactance, secondary side harmonic wave equivalent resistance, the primary side being sequentially connected in series
Harmonic wave equivalent reactance, primary side harmonic wave equivalent resistance；It is equivalent in the secondary side harmonic wave equivalent resistance and the primary side harmonic wave
It is also associated with that the equivalent excitation resistance harmonic of harmonic wave that is serially connected is equivalent to encourage between node and the current source between reactance
Magnetoelectricity resists；The equivalent excitation resistance of the harmonic wave and the equivalent excitation reactance of the harmonic wave are obtained according to the harmonic wave equivalent circuit.
Further, step S4 is further included：Measure load loss P of the converter power transformer under power frequency1；One
The load loss P under the frequency is obtained under individual low frequency high currenth；The vortex for calculating winding under power frequency by simultaneous below equation is damaged
Consumption Pwe,1With stray loss P in hardware under power frequencyse,1：
Wherein,For resistance loss, I1For power current virtual value, IhFor h subharmonic current virtual values；According to each
The virtual value and P of electric current under frequencywe,1, Pse,1Calculate the loss P under each frequencyh；According to the loss P under each frequencyhCarry out
Summation obtains load loss.
The additional aspect and advantage of the present invention will be set forth in part in the description, and partly will become from the following description
Obtain substantially, or recognized by the practice of the present invention.
Description of the drawings
The above-mentioned and/or additional aspect and advantage of the present invention will become from the description with reference to accompanying drawings below to embodiment
It is substantially and easy to understand, wherein：
Fig. 1 is the flow chart of the bearing calibration of the converter power transformer load loss situ measurements of the embodiment of the present invention；
Fig. 2 is the circuit diagram of the harmonic wave equivalent circuit of one embodiment of the invention；
Fig. 3 is the circuit diagram of the harmonic wave equivalent circuit in correlation technique.
Specific embodiment
Embodiments of the invention are described below in detail, the example of the embodiment is shown in the drawings, wherein from start to finish
Same or similar label represents same or similar element or the element with same or like function.Below with reference to attached
The embodiment of figure description is exemplary, is only used for explaining the present invention, and is not considered as limiting the invention.
In describing the invention, it is to be understood that term " " center ", " longitudinal direction ", " horizontal ", " on ", D score,
The orientation or position relationship of the instruction such as "front", "rear", "left", "right", " vertical ", " level ", " top ", " bottom ", " interior ", " outward " is
Based on orientation shown in the drawings or position relationship, it is for only for ease of the description present invention and simplifies description, rather than indicates or dark
Showing the device or element of indication must have specific orientation, with specific azimuth configuration and operation therefore it is not intended that right
The restriction of the present invention.Additionally, term " first ", " second " are only used for describing purpose, and it is not intended that indicating or implying relative
Importance.
In describing the invention, it should be noted that unless otherwise clearly defined and limited, term " installation ", " phase
Company ", " connection " should be interpreted broadly, for example, it may be being fixedly connected, or being detachably connected, or be integrally connected；Can
Being to be mechanically connected, or electrically connect；Can be joined directly together, it is also possible to be indirectly connected to by intermediary, Ke Yishi
The connection of two element internals.For the ordinary skill in the art, with concrete condition above-mentioned term can be understood at this
Concrete meaning in invention.
With reference to explained below and accompanying drawing, it will be clear that these and other aspects of embodiments of the invention.In these descriptions
In accompanying drawing, specifically disclose some particular implementations in embodiments of the invention to represent the enforcement for implementing the present invention
Some modes of the principle of example, but it is to be understood that the scope of embodiments of the invention is not limited.Conversely, the present invention
Embodiment includes all changes, modification and the equivalent fallen into the range of the spirit and intension of attached claims.
Below in conjunction with the school of Description of Drawings converter power transformer load loss situ measurements according to embodiments of the present invention
Correction method.
Fig. 1 is the flow process of the bearing calibration of the converter power transformer load loss situ measurements of one embodiment of the invention
Figure.
A kind of bearing calibration of converter power transformer load loss situ measurements, comprises the following steps：
S1：Load test is carried out to converter power transformer before dispatching from the factory, the harmonic loss model of converter power transformer is obtained.
In one embodiment of the invention, the harmonic loss model of converter power transformer includes harmonic wave equivalent circuit.Such as Fig. 2
Shown, harmonic wave equivalent circuit includes current source, the additional impedance Z being sequentially connected in seriesn(f), secondary side harmonic wave equivalent reactance Xn(2), it is secondary
Side harmonic wave equivalent resistance Rn(2), primary side harmonic wave equivalent reactance Xn(1), primary side harmonic wave equivalent resistance Rn(1)；In secondary side harmonic wave
Equivalent resistance Rn(2)And the nodes X between primary side harmonic wave equivalent reactancen(1)Be also associated with being serially connected between current source is humorous
The equivalent excitation resistance R of ripplen(m)The equivalent excitation reactance X of harmonicn(m).N represents overtone order in above-mentioned parameter.
S2：Load test is carried out after dispatching from the factory, harmonic current waveforms are obtained.
S3：Fourier analysis is carried out to harmonic current waveforms, the current effective value under each harmonic frequency is obtained.
S4：Each harmonic wave frequency is obtained according to the current effective value under the harmonic loss model and each harmonic frequency of converter power transformer
The load loss of the converter power transformer under rate.
In one embodiment of the invention, step S4 is further included：
Setting eddy-current loss be proportional to electric current and frequency square, stray loss is proportional to the quadratic sum frequency of electric current
0.8 power.Total losses are lost by D.C. resistance, eddy-current loss and the part of stray loss three are constituted.Fundamental wave to converter power transformer
Loss harmonic loss is respectively adopted following two formula and calculates.
In formula：Resistance loss (W)；Pwe,1：The eddy-current loss (W) of winding under power frequency；Pse,1：Metal knot under power frequency
Stray loss (W) in component；I1：Power current virtual value (A)；Ih：H subharmonic current virtual values (A)；F1：Power frequency 50Hz；
Fh：H subfrequencies (Hz).
According to the method that IEC is provided, the solution of load loss can be divided into following step：First, the change of current is measured
Load loss P of the transformer under power frequency1, the load loss P under the frequency is then obtained under a low frequency high currenth, pass through
Two formulas calculate P on simultaneouswe,1And Pse,1, finally according to the virtual value and P of electric current under each frequencywe,1, Pse,1, calculate the frequency
Under loss Ph, load loss PcObtained by summation.
S5：Judge the load loss and the converter power transformer obtained by measurement of the converter power transformer under each harmonic frequency
Whether in preset range, the iron core of converter power transformer is not deformed upon the difference of load loss if in preset range,
The intimate of converter power transformer is deformed upon if beyond preset range.
After iron core is deformed upon, revised harmonic wave containing additional impedance of converter power transformer etc. is calculated by procedure below
Additional impedance in effect circuit：
S501：The virtual value of fundamental current harmonic electric current is set.
S502：Under the conditions of 1 to 49 secondary frequencies, harmonic loss is calculated with IEC methods and common harmonic wave equivalent circuit respectively
Pk1And Pk2；Wherein, Pk1It is method is tried to achieve in step S4 under k subharmonic loss result, Pk2It is with common under k subharmonic
The loss result that harmonic wave equivalent circuit method is tried to achieve.
Specifically, common harmonic wave equivalent circuit is as shown in Figure 3.According to the idling load-loss of converter power transformer shop test
Measurement result and famous brand parameter, are calculated as follows：
It is perunit value with asterisk in computing formula, is actual value without asterisk, can be between perunit value and actual value
Mutually conversion.Under the conditions of fundamental frequency, n=1, now, subscript n can be omitted, and following calculating process refer both to the electricity under the conditions of fundamental frequency
Road parameter.In engineering, it is generally recognized that：
It is as follows to the concrete solution procedure of its circuit parameter：
Wherein, subscript k represents total parameter of resistance.ZkRepresent total impedance, UkRepresent total voltage, IkRepresent total current, RkGeneration
Table all-in resistance, XkRepresent total reactance.
In order to more accurately solve, it is possible to use following formula solves Rm, Xm：
The R that substitution is tried to achieve1、R2And X1、X2Actual value, to Rm, XmCalculated, P0Load loss is represented, according to P0
Obtain Pk2。
S503：With loss difference divided by harmonic current square, obtain the additional resistance (under k subharmonic) under the frequency
Value：
Wherein, IkBe the first step arrange k subharmonic current virtual values, RkIt is k subharmonic additional electrical resistances.
S504：The reactive loss calculated using equivalent circuit, obtains the reactance value under the frequency：
Wherein, Qk2Be with equivalent circuit calculate reactive power value, XkIt is k additional reactance value.
S505：To RkFitting of a polynomial is carried out, the expression formula of additional resistance is tried to achieve.
In addition, other compositions of the bearing calibration of the converter power transformer load loss situ measurements of the embodiment of the present invention
And effect is all for a person skilled in the art known, in order to reduce redundancy, is not repeated.
In the description of this specification, reference term " one embodiment ", " some embodiments ", " example ", " specifically show
The description of example " or " some examples " etc. means to combine specific features, structure, material or spy that the embodiment or example are described
Point is contained at least one embodiment of the present invention or example.In this manual, to the schematic representation of above-mentioned term not
Necessarily refer to identical embodiment or example.And, the specific features of description, structure, material or feature can be any
One or more embodiments or example in combine in an appropriate manner.
Although an embodiment of the present invention has been shown and described, it will be understood by those skilled in the art that：Not
These embodiments can be carried out with various changes, modification, replacement and modification in the case of the principle and objective that depart from the present invention, this
The scope of invention is limited by claim and its equivalent.
Claims (3)
1. a kind of bearing calibration of converter power transformer load loss situ measurements, it is characterised in that comprise the following steps：
S1：Load test is carried out to converter power transformer before dispatching from the factory, the harmonic loss model of the converter power transformer is obtained；
S2：Load test is carried out after dispatching from the factory, harmonic current waveforms are obtained；
S3：Fourier analysis is carried out to the harmonic current waveforms, the current effective value under each harmonic frequency is obtained；
S4：Obtain each humorous according to the current effective value under the harmonic loss model and each harmonic frequency of the converter power transformer
The load loss of the converter power transformer under wave frequency rate,；
S5：Judge the load loss and the change of current transformation obtained by measurement of the converter power transformer under each harmonic frequency
Whether in preset range, the iron core of the converter power transformer does not have the difference of the load loss of device if in the preset range
Deform upon, the iron core of the converter power transformer is deformed upon if beyond the preset range.
2. the bearing calibration of converter power transformer load loss situ measurements according to claim 1, it is characterised in that
The harmonic loss model of the converter power transformer includes harmonic wave equivalent circuit, and the harmonic wave equivalent circuit includes the electricity being sequentially connected in series
Stream source, additional impedance, secondary side harmonic wave equivalent reactance, secondary side harmonic wave equivalent resistance, primary side harmonic wave equivalent reactance, primary side
Harmonic wave equivalent resistance；Node between the secondary side harmonic wave equivalent resistance and the primary side harmonic wave equivalent reactance with it is described
The equivalent excitation reactance of the equivalent excitation resistance harmonic of harmonic wave being serially connected is also associated between current source.
3. the bearing calibration of converter power transformer load loss situ measurements according to claim 1, it is characterised in that
Step S4 is further included：
Measure load loss P of the converter power transformer under power frequency1；
The load loss P under the frequency is obtained under a low frequency high currenth；
Eddy-current loss P of winding under power frequency is calculated by simultaneous below equationwe,1With the stray loss in hardware under power frequency
Pse,1：
Wherein,For resistance loss, I1For power current virtual value, IhFor h subharmonic current virtual values, F1For power frequency 50Hz,
FhFor h subfrequencies；
According to the virtual value and P of electric current under each frequencywe,1, Pse,1Calculate the loss P under each frequencyh；According under each frequency
Loss PhCarry out summation and obtain load loss.
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Cited By (5)
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| CN110118905A (en) * | 2019-04-28 | 2019-08-13 | 福建省大岩电子科技有限公司 | A kind of isolating transformer equivalent load test method applied under harmonic condition |
| CN110118904A (en) * | 2019-04-28 | 2019-08-13 | 东莞市大忠电子有限公司 | A kind of k-factor transformer equivalent load conversion method |
| CN110196361A (en) * | 2019-04-28 | 2019-09-03 | 福建省大岩电子科技有限公司 | A kind of common transformer is applied to the drop volume calculation method under harmonic condition |
| CN112462180A (en) * | 2020-11-18 | 2021-03-09 | 西安交通大学 | Converter transformer loss measuring method |
| CN112578187A (en) * | 2020-11-23 | 2021-03-30 | 清华大学 | High-frequency transformer loss measurement system and method |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110118905A (en) * | 2019-04-28 | 2019-08-13 | 福建省大岩电子科技有限公司 | A kind of isolating transformer equivalent load test method applied under harmonic condition |
| CN110118904A (en) * | 2019-04-28 | 2019-08-13 | 东莞市大忠电子有限公司 | A kind of k-factor transformer equivalent load conversion method |
| CN110196361A (en) * | 2019-04-28 | 2019-09-03 | 福建省大岩电子科技有限公司 | A kind of common transformer is applied to the drop volume calculation method under harmonic condition |
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| CN110118904B (en) * | 2019-04-28 | 2021-12-14 | 东莞市大忠电子有限公司 | K-coefficient transformer equivalent load conversion method |
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| CN112462180B (en) * | 2020-11-18 | 2021-08-27 | 西安交通大学 | Converter transformer loss measuring method |
| CN112578187A (en) * | 2020-11-23 | 2021-03-30 | 清华大学 | High-frequency transformer loss measurement system and method |
| CN112578187B (en) * | 2020-11-23 | 2022-02-08 | 清华大学 | High-frequency transformer loss measurement system and method |
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