CN109444776A - Three-phase full-bridge converter iron core remanent magnetism measuring method, system and storage medium - Google Patents
Three-phase full-bridge converter iron core remanent magnetism measuring method, system and storage medium Download PDFInfo
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- CN109444776A CN109444776A CN201811307106.0A CN201811307106A CN109444776A CN 109444776 A CN109444776 A CN 109444776A CN 201811307106 A CN201811307106 A CN 201811307106A CN 109444776 A CN109444776 A CN 109444776A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R33/00—Arrangements or instruments for measuring magnetic variables
- G01R33/12—Measuring magnetic properties of articles or specimens of solids or fluids
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R33/00—Arrangements or instruments for measuring magnetic variables
- G01R33/12—Measuring magnetic properties of articles or specimens of solids or fluids
- G01R33/14—Measuring or plotting hysteresis curves
Abstract
The invention discloses a kind of three-phase full-bridge converter iron core remanent magnetism measuring methods, estimate three-phase full-bridge converter remnant magnetism state.Method includes the following steps: obtaining the saturation hysteresis loop of transformer core；Parameter identification is carried out to the saturation hysteresis loop of transformer core, establishes transformer core hysteresis characteristic model；The Slope relationship of remanent magnetism and hysteresis loop is obtained according to transformer core hysteresis characteristic model；And to the relation formula of remanent magnetism and hysteresis loop slope；Establish three-phase full-bridge converter UMEC magnetic circuit model；Three-phase coil is positive and negative to inductance value when obtaining three-phase full-bridge converter iron core energizing test to be measured, obtains the positive negative sense slope near remanent magnetism point according to inductance value and UMEC magnetic circuit model, calculates residual induction further according to the relationship of remanent magnetism and hysteresis loop slope.The method of the present invention is simple, and remanent magnetism measuring and calculating experiment need to only apply forward and reverse small excitation and record to voltage and current, and without complicated online experiment, test power is small, and experimental cost is low.
Description
Technical field
The invention belongs to power transmission technical fields, and in particular to a kind of three-phase full-bridge converter iron core remanent magnetism measuring method.
Background technique
Power transformer is unloaded or underloading closes a floodgate and is powered, and the presence of remanent magnetism can make the quick half cycle of transformer core full in iron core
With generate amplitude up to 6~8 times of normal steady state electric current of excitation surge current.Biggish excitation surge current includes a large amount of harmonic waves, influences electricity
Energy quality, causes protective relaying maloperation to make, influences the safe operation of power grid.Synchronous Closing Technology is current with phase selection switch technology
Inhibit excitation surge current effective measures, and when effective measuring and calculating in remanent magnetism size and direction phase selection switch technology premise.
Correlative study is done to transformer remanent magnetism evaluation method both at home and abroad, wherein main method has:
1) remanent magnetism is identified according to the saturation moment, and establishes transformer separating brake angle and the method for the relation property of iron core remanent magnetism is estimated
Remanent magnetism is calculated, but this method needs to carry out transformer a large amount of air-drop experiment, and is saturated accurately identifying for moment and needs to rely on
The variation of inductance, therefore remanent magnetism accuracy of identification is not high；
2) continuous function, arctan function and preisach model are utilized respectively and describes iron core magnetic characteristic, by separating brake
The record of moment current amplitude and phase estimates remanent magnetism, but the magnetic after transformer separating brake in iron core using minor loop
Logical variation is the complicated transient process influenced by factors such as transformer equivalent capacitys, is difficult to retouch by simple mathematical model
It states；
3) the temporal variations process based on iron core magnetic flux after JA model analysis separating brake is proposed surplus based on JA hysteresis model
Magnetic evaluation method；
4) it to there are the small excitation that the transformer of certain remanent magnetism applies different directions, is rung by analysis remanent magnetism and different directions
The direction of the relationship estimation remanent magnetism for the difference answered and size.
The above remanent magnetism evaluation method needs to record the magnitude of current at separating brake moment mostly, and has to three-phase full-bridge converter application
There is certain limitation, there is certain meaning to the magnetic characteristic analysis of iron core, but not strong to Practical Project transformer application.
Summary of the invention
It is an object of the invention to overcome deficiency in the prior art, the measuring and calculating of three-phase full-bridge converter iron core remanent magnetism is provided
Method does not need the magnitude of current at record separating brake moment, can obtain remanent magnetism according to remanent magnetism and minor loop's Slope relationship
Size and direction.
The present invention is achieved by the following technical solutions:
In a first aspect, providing a kind of three-phase full-bridge converter iron core remanent magnetism measuring method, the method includes walking as follows
It is rapid:
Obtain the saturation hysteresis loop of transformer core；
Parameter identification is carried out to the saturation hysteresis loop of transformer core, establishes transformer core hysteresis characteristic model；
Remanent magnetism and the hysteresis loop (local hysteresis time near remanent magnetism point are obtained according to transformer core hysteresis characteristic model
Line) Slope relationship；And to the relation formula of remanent magnetism and hysteresis loop slope；
Establish three-phase full-bridge converter UMEC magnetic circuit model；
Three-phase coil is positive and negative to inductance value when obtaining three-phase full-bridge converter iron core energizing test to be measured, according to inductance
Value obtains the positive negative sense slope near remanent magnetism point with UMEC magnetic circuit model, calculates further according to the relationship of remanent magnetism and hysteresis loop slope
Residual induction.
With reference to first aspect, further, the transformer core hysteresis characteristic model is as follows:
B=μ0(M+H) (6)
He=H+ α M (7)
Wherein, M is the intensity of magnetization, and B is magnetic induction intensity, and H is magnetic field strength, μ0For space permeability, MsFor saturated magnetization
Intensity, a are ideal magnetization curve form parameter, and k is magnetic hystersis loss parameter, and α coupling parameter between magnetic domain, β is model parameter, m
For susceptibility, ManFor anhysteretic intensity, HeFor effective magnetic field intensity, x is effectively to cut down magnetic field strength, and δ is the reaction side B
To amount, take 1 or -1, δMThe amount for leading to non-physical solution to eliminate the direction B suddenly change and introducing, BJFor Brillouin function, J
For the quantum number for reacting anisotropic degree, R (m) is anisotropic function；
When calculating minor loop:
A=a1=amaexp(σ1(Bs-Bmax))； (8)
α=α1=αmaexp(λ1(Bs-Bmax))； (9)
K=k1=kmaexp(-γ1(Bs-Bmax))； (10)
Wherein, ama、αma、kmaThe original value of a, α, k parameter respectively in transformer core hysteresis characteristic model；σ1、λ1、
γ1For the corrected parameter of parameter a, α, k of model after being improved for minor loop, a1、α1、k1Respectively returned for small magnetic hysteresis
The value of parameter a, α, k of model after line improves, Bs are the saturation value of saturation hysteresis loop, BmaxFor the saturation value of minor loop；
When calculating minor loop:
a2=a1exp(σ2(Bs-Brev)) (11)
α2=α1exp(λ2(Bs-Brev)) (12)
k2=k1exp(-γ2(Bs-Brev)) (13)
β2=βmaexp(-ξ2(Bs-Brev)) (14)
Wherein, βmaFor the original value of β parameter in transformer core hysteresis characteristic model, β2To change for minor loop
Into the value of the parameter beta of rear model；σ2、λ2、γ2、ξ2It is repaired for parameter a, α, k, β of model after being improved for minor loop
Correct parameter；BrevThe value of the magnetic induction density B of saturation hysteresis loop position where minor loop.
With reference to first aspect, further, it is described using object optimizing method to the saturation hysteresis loop of transformer core into
Row parameter identification includes:
It will be saturation magnetization Ms, ideal magnetization curve form parameter a, coupling parameter α, magnetic hystersis loss parameter between magnetic domain
K and model parameter β assigns initial value, then to test the magnetic induction density B obtainedexpAs transformer core hysteresis characteristic model
The input quantity of middle B finds out magnetic field strength H at this timesim, it is then found out again and tests magnetic field strength H obtainedexpBetween it is equal
VarianceAgain with EmseFor feedback quantity control parameter Ms, a, α, k, β variation, make EmseMinimum,
And according to M at this times, a, α, k, β determine model, n is the H that experiment obtainsexpNumber.
With reference to first aspect, further, the relation formula to remanent magnetism and hysteresis loop slope includes:
Fitting of a polynomial is carried out to the relationship of minor loop's slope near remanent magnetism and remanent magnetism point, obtains fitting formula:
Wherein C, D, E, F, G, I are fitting coefficient, BrFor residual induction, μrFor minor loop's slope.
With reference to first aspect, further, three-phase full-bridge converter UMEC magnetic circuit model is established using following equation:
A=[1 1 1]T (15)
P=diag (Pa,Pb,Pc) (16)
R=P-PA (ATPA)-1ATP (17)
Lss=N2Mss (18)
Wherein, A is magnetic flux incidence matrix, and P is three-phase full-bridge converter iron core magnetic conductance matrix, Pa,Pb,PcRespectively A, B, C
Three-phase stem iron core magnetic conductance, Mss are the matrix in block form that winding coil is corresponded in matrix R, and p is the magnetic conductance of three-phase magnetic circuit, μrFor office
The slope of portion's hysteresis loop, s are the cross-sectional area of magnetic circuit, and l is the length of magnetic circuit, and N is the coil turn of each phase winding, and Lss is
The equivalent inductance of winding, r are the series resistance of circuit, and u and i are respectively the voltage and current at coil both ends, and t is the time.
With reference to first aspect, further, the triple line after obtaining three-phase full-bridge converter iron core energizing test to be measured
That encloses is positive and negative to inductance value, the positive negative sense slope near remanent magnetism point is obtained according to inductance value and UMEC magnetic circuit model, further according to surplus
The relationship of magnetic and hysteresis loop slope calculates residual induction
Positive small excitation is applied to A phase coil, the voltage and current at measuring coil both ends calculates the positive inductance of A phase coil；
The small excitation of negative sense is applied to A phase coil, the voltage and current at measuring coil both ends calculates the negative sense inductance of A phase coil；
Similarly B, C phase coil are applied respectively positive and negative to small excitation, the positive inductance and negative sense electricity of calculating B, C phase coil
Sense, the above small excitation apply all in accordance with empirical value；Calculated the positive and negative of A, B, C three-phase coil is updated to UMEC to inductance
The positive and negative slope to minor loop of A, B, C three-phase is calculated in magnetic circuit model；Further according to remanent magnetism and hysteresis loop slope
Relation formula obtain each stem remanent magnetism of transformer.
Second aspect provides a kind of three-phase full-bridge converter iron core remanent magnetism calculating system, comprising:
Acquisition module: for obtaining the saturation hysteresis loop of transformer core；
Hysteresis characteristic model foundation modeling module: for the saturation hysteresis loop using object optimizing method to transformer core
Parameter identification is carried out, transformer core hysteresis characteristic model is established；
Formula determining module: the slope for obtaining remanent magnetism and hysteresis loop according to transformer core hysteresis characteristic model closes
System；And to the relation formula of remanent magnetism and hysteresis loop slope；
Magnetic circuit model modeling module: for establishing three-phase full-bridge converter UMEC magnetic circuit model；
Calculation of residual flux module: for obtaining the positive and negative of three-phase coil after three-phase full-bridge converter iron core energizing test to be measured
To inductance value, the positive negative sense slope near remanent magnetism point is obtained according to inductance value and UMEC magnetic circuit model, further according to remanent magnetism and magnetic hysteresis
The relationship of loop line slope calculates residual induction.
The third aspect provides a kind of three-phase full-bridge converter iron core remanent magnetism calculating system, including memory and processor；
The memory is for storing instruction；
The processor according to described instruction for being operated to execute the step of first aspect any one the method
Suddenly.
Fourth aspect provides a kind of computer readable storage medium, is stored thereon with computer program, and the program is processed
The step of first aspect any one the method is realized when device executes.
To sum up, three-phase full-bridge converter iron core remanent magnetism measuring method, system and storage medium provided by the invention, by building
Vertical transformer core hysteresis characteristic model (model is based on JA model refinement) surveys three-phase full-bridge converter iron core remanent magnetism
It calculates, parameter is few, precision is high, and remanent magnetism measuring method is simple, as a result accurately；And remanent magnetism measuring and calculating experiment need to only apply forward and reverse small sharp
It encourages and voltage and current is recorded, without complicated online experiment, test power is small, and experimental cost is low.
Detailed description of the invention
Fig. 1 is hysteresis measurement experimental principle figure；
Fig. 2 is original JA model minor loop schematic diagram before correcting；
Fig. 3 is JA model minor loop schematic diagram after amendment；
Fig. 4 is JA model minor loop schematic diagram before correcting；
Fig. 5 is JA model minor loop schematic diagram after amendment；
Fig. 6 is object optimizing method to JA Model Parameter Optimization flow chart；
Fig. 7 is the hysteresis loop figure of experiment measurement hysteresis loop and JA model optimization；
Fig. 8 is the relational graph of remanent magnetism and positive slope；
Fig. 9 is the relational graph of remanent magnetism and negative sense slope；
Figure 10 is the UMEC magnetic circuit model figure that three-phase three-limb transformer ignores leakage field.
Specific embodiment
The invention will be further described below in conjunction with the accompanying drawings.Following embodiment is only used for clearly illustrating the present invention
Technical solution, and not intended to limit the protection scope of the present invention.
Term is explained
Hysteresis characteristic: original non-magnetic ferromagnetic material is placed in certain externally-applied magnetic field, and ferromagnetic material will obtain magnetism simultaneously
A new magnetic field, referred to as induced magnetic field are generated, intensity is known as magnetic induction density B, and the intensity of externally-applied magnetic field is known as magnetic field strength
H.When applied field strengths H changes, magnetic induction density B also changes therewith, but the magnetic induction density B in ferromagnetic material
Variation is lagging behind in the variation of externally-applied magnetic field H, thus make the B-H relationship of Ferromagnetic Material that a loop curve being closed be presented,
Referred to as hysteresis loop.
As Figure 1-10 shows, the present invention provides a kind of three-phase full-bridge converter iron core remanent magnetism measuring methods includes:
Step 1: the saturation hysteresis loop of transformer core is obtained by measurement.
As shown in Figure 1, applying low-frequency ac electric current (simultaneously here for measurement saturation hysteresis loop to one lateral coil of transformer
Corresponding JA model parameter is obtained with this, therefore low-frequency ac electric current should be applied.), frequency is generally taken as 5HZ, amplitude according to
Depending on core material magnetic hysteresis is specific, to the voltage and current data record at coil both ends, and voltage-current relation is converted into magnetic
Relationship between induction B and magnetic field strength H,
Transfer equation is as follows:
H=Ni/L (22)
B=∫ (u/NS) dt (23)
Wherein, N is coil turn, and L is magnetic circuit equivalent length, and u is coil both end voltage, and i is coil both ends electric current, and S is
Core section product, t is the time.
The saturation hysteresis loop of corresponding transformer fe core material is measured, with Baosteel trade mark B23P085 ring transformer cores
For, measurement saturation hysteresis loop is as shown in Figure 7.
Step 2: parameter identification is carried out to the saturation hysteresis loop of transformer core, establishes transformer core hysteresis characteristic
Model.
The saturation hysteresis loop of JA (Jiles-Atherton) model emulation iron core is used first；
Jiles-Atherton hysteresis model is the hysteresis model that the domain wall theory based on ferromagnetic material is set up, and is mesh
The mathematical model of widely used description magnetization curve in preceding engineering.JA model considers that magnetic domain wall moving and energy balance are former
Reason obtains the relation equation of magnetization M and magnetic field strength H.Since electrical transformer cores mostly use anisotropic material, because
This present invention is carried out using the JA model for being directed to anisotropic material, and for minor loop, minor loop's description
It improves, fundamental equation is as follows:
B=μ0(M+H) (6)
He=H+ α M (7)
Wherein, M is the intensity of magnetization, and B is magnetic induction intensity, and H is magnetic field strength, μ0For space permeability, MsFor saturated magnetization
Intensity, a are ideal magnetization curve form parameter, and k is magnetic hystersis loss parameter, and α coupling parameter between magnetic domain, β is model parameter, m
For susceptibility, ManFor anhysteretic intensity, HeFor effective magnetic field intensity, x is effectively to cut down magnetic field strength, and δ is the reaction side B
To amount, take 1 or -1, δMThe amount for leading to non-physical solution to eliminate the direction B suddenly change and introducing, BJFor Brillouin function, J
For the quantum number for reacting anisotropic degree, R (m) is anisotropic function；
In order to enable model expression to indicate the actual hysteresis characteristic of the iron core, adjusting parameter is needed to go out model emulation
The saturation hysteresis loop that goes out of saturation hysteresis loop and step 1 actual measurement match (as shown in Figure 7), need to JA model
Ms, k, a, this five parameters of α, β are adjusted.
Basic step are as follows: will be saturation magnetization Ms, ideal magnetization curve form parameter a, coupling parameter α between magnetic domain,
Magnetic hystersis loss parameter k and model parameter β assigns initial value, then to test the magnetic induction density B obtainedexpAs transformer core
The input quantity of B in hysteresis characteristic model, finds out magnetic field strength H at this timesim, it is strong with experiment magnetic field obtained that it is then found out again
Spend HexpBetween mean square deviationAgain with EmseFor feedback quantity control parameter Ms, a, α, k, β change
Change, makes EmseMinimum, and according to M at this times, a, α, k, β determine model, n is the H that experiment obtainsexpNumber.
According to improvement JA model determined above, the index for carrying out parameter for minor loop and minor loop turns
Repair just, adjusts corrected parameter σ, γ, λ, ξ, makes revised improvement JA model reliable conveyance.
When calculating minor loop:
A=a1=amaexp(σ1(Bs-Bmax))； (8)
α=α1=αmaexp(λ1(Bs-Bmax))； (9)
K=k1=kmaexp(-γ1(Bs-Bmax))； (10)
Wherein, ama、αma、kmaThe original value of a, α, k parameter respectively in transformer core hysteresis characteristic model；σ1、λ1、
γ1For the corrected parameter of parameter a, α, k of model after being improved for minor loop, a1、α1、k1Respectively returned for small magnetic hysteresis
The value of parameter a, α, k of model after line improves, Bs are the saturation value of saturation hysteresis loop, BmaxFor the saturation value of minor loop；
When calculating minor loop:
a2=a1exp(σ2(Bs-Brev)) (11)
α2=α1exp(λ2(Bs-Brev)) (12)
k2=k1exp(-γ2(Bs-Brev)) (13)
β2=βmaexp(-ξ2(Bs-Brev)) (14)
Wherein, βmaFor the original value of β parameter in transformer core hysteresis characteristic model, β2To change for minor loop
Into the value of the parameter beta of rear model；σ2、λ2、γ2、ξ2It is repaired for parameter a, α, k, β of model after being improved for minor loop
Correct parameter；BrevThe value of the magnetic induction density B of saturation hysteresis loop position where minor loop.
Before amendment, JA model describes the later half segment description as shown in figure 4, to minor loop to minor loop
There are non-physical solutions.Take Brev=0.758, adjust corrected parameter σ2、γ2、λ2、ξ2, revised model is to minor loop
The non-physical solution of second half section can be solved preferably, and JA model is as shown in Figure 5 to the description of minor loop after amendment.
Step 3: it is big to obtain remanent magnetism for the hysteresis characteristic indicated according to the transformer core hysteresis characteristic model of above-mentioned acquisition
The relationship of positive negative sense minor loop slope near small and direction and remanent magnetism point, and relationship between the two is fitted into formulation
Obtain fitting formula
Wherein C, D, E, F, G, I are fitting coefficient, BrFor residual induction, μrFor minor loop's slope.
The value of B when remanent magnetism, i.e. H=0, the point (H being reflected as in B-H reference axis on axis of ordinates positive axis0, B0)=(0,
Br)
By H=H0=Hr=0, B=B0=BrIt substitutes into formula (6) and obtains the initial value M of M0, with M0, B0Respectively as differential side
The initial value of M and B, B in journey, that is, formula (1)Q=BQ-1+△B；Empirically value takes a number of very little to △ B；That is calculating process
In each step B changing value, △ B can be negative value, and illustrating to calculate when △ B is negative value is that remanent magnetism point is left in reference axis
The point on side, i.e. next point of negative sense minor loop, being calculated when △ B is positive value is positive minor loop
Next point.
With the numerical solution solution formula (1) of the differential equation, dM/dB is calculated i.e.△ can be acquired by acquiring in turn
M, B1=B0+ △ B, M1=M0+ △ M is then obtained by formula (6)To obtain next point (H of hysteresis loop1,
B1), (H can similarly be calculated2, B2)(H3, B3)……(HQ, BQ), by the forward direction near the connected as remanent magnetism point of these points
Or negative sense minor loop；
Wherein, H0、B0、M0Respectively magnetic field strength, magnetic induction intensity and the intensity of magnetization of remanent magnetism point, H1、B1、M1Respectively
For magnetic field strength, magnetic induction intensity and the intensity of magnetization of first point on hysteresis loop near remanent magnetism point, HQ、BQIt is respectively surplus
The magnetic field strength of the Q point, magnetic induction intensity on the neighbouring hysteresis loop of magnetic dot, △ B, △ M are respectively adjacent two on hysteresis loop
The variable quantity of magnetic induction intensity and the intensity of magnetization between point；
Pass through formula (BQ-Br)/(HQ–Hr) remanent magnetism point (H is calculated0, B0) i.e. (0, Br) neighbouring minor loop
Slope；
By choosing different B0Value, calculates different B0The slope of the corresponding minor loop of value, can be obtained
The relationship of the relationship of the neighbouring minor loop's slope of remanent magnetism and remanent magnetism point, remanent magnetism and positive slope is as shown in figure 8, remanent magnetism and negative
Relationship to slope is as shown in Figure 9.
Fitting of a polynomial is taken to carry out formulation processing to remanent magnetism Slope relationship at this time, fitting formula:
Wherein C, D, E, F, G, I are fitting coefficient, BrFor residual induction, μrFor minor loop's slope.
Step 4: being powered to transformer core to be measured and obtain voltage and current value, is then remained by electromagnetic relationship conversion
Positive negative sense slope near magnetic dot calculates remanent magnetism according to the formula that previous step obtains.
Step 1 is directed to a certain core material of transformer use to the remanent magnetism slope curve obtained in three,
That is no matter single-phase or three-phase, as long as be the material, remanent magnetism Slope relationship is considered identical.
For three-phase three-limb transformer, remanent magnetism estimates that experiment flow is as follows:
The cross-sectional area of three-phase three-limb transformer stem, other column and iron yoke is identical, therefore, it is considered that being connected with column by A phase
Iron yoke up and down in remanent magnetism BR, A iron yokeWith the remanent magnetism B of column by A phaseColumn by r, AEqual, C phase is same.It only needs to calculate by A phase
Column, B phase stem, by C phase column remanent magnetism.
The UMEC magnetic circuit model that three-phase three-limb transformer ignores leakage field is as shown in Figure 10.
In Figure 10, since the remanent magnetism of A, B, C three-phase is different, the magnetic conductance of three-phase magnetic circuit is different, is denoted as P respectivelyA, PB,
PC, by formula (20) it is found that the magnetic conductance P of three-phase magnetic circuit should be with differential permeability μrVariation and change, but due to remanent magnetism survey
When calculation, the excitation amplitude very little of application, therefore slope, that is, differential permeability of the minor loop near remanent magnetism point is made into line
Propertyization processing, that is, think the slope i.e. differential permeability μ of the minor loop in the case of small excitation near remanent magnetism pointrIt is normal
Number, that is, think PA, PB, PCIt is constant in the case where small excitation, therefore the UMEC magnetic circuit model of three-phase three-limb transformer is as follows
Formula,
A=[1 1 1]T (15)
P=diag (Pa,Pb,Pc) (16)
R=P-PA (ATPA)-1ATP (17)
Lss=N2Mss (18)
In formula (17), R is 3 × 3 matrixes, remembers that its main diagonal element is respectively Maa, Mbb, Mcc
Wherein, A is magnetic flux incidence matrix, and P is the magnetic conductance of three-phase magnetic circuit, as three-phase full-bridge converter iron core magnetic conductance square
Battle array, i.e., the diagonal matrix of each magnetic circuit magnetic conductance, Pa,Pb,PcRespectively A, B, C three-phase stem iron core magnetic conductance, calculation formula are shown in formula
(20), in formula (20), P respectively represents Pa,Pb,Pc；Mss (respectively represents M to correspond to the matrix in block form of winding coil in matrix Raa、
Mbb、Mcc), μrFor the slope of minor loop, s is the cross-sectional area of magnetic circuit, and l is the length of magnetic circuit, and N is the line of each phase winding
The number of turns is enclosed, Lss is the equivalent inductance of winding, and r is the series resistance of circuit, respectively represents Laa、Lbb、Lcc, u and i are respectively coil
The voltage and current at both ends, t are the time.
Step 5: three-phase coil is positive and negative to inductance value, root when obtaining three-phase full-bridge converter iron core energizing test to be measured
The positive negative sense slope near remanent magnetism point is obtained according to inductance value and UMEC magnetic circuit model, further according to the pass of remanent magnetism and hysteresis loop slope
System's measuring and calculating residual induction.
Step 51, positive small excitation is applied to A phase coil, to the voltage and current measurement at coil both ends, according to formula (21)
The positive inductance for calculating A phase coil (illustrates LssIn generation, refers to L respectivelyaa、Lbb、Lcc)；The small excitation of negative sense is applied to A phase coil, to coil
The voltage and current measurement at both ends calculates the negative sense inductance of A phase coil according to formula (21)；
Step 52, similarly, B, C phase coil are applied respectively positive and negative to small excitation, the positive inductance of calculating B, C phase coil
With negative sense inductance；The above small excitation applies all in accordance with empirical value.
Step 53, the inductance L being calculated according to step 51 and 52aa、Lbb、Lcc, bring formula (18) into and calculate separately Maa、
Mbb、Mcc；By Maa、Mbb、MccIt brings formula (18) into and calculates PA, PB, PC；By PA, PB, PCIt brings formula (20) into and calculates the micro- of A, B, C three-phase
Divide magnetic permeability μrA、μrB、μrC；By μrA、μrB、μrCBring the residual induction that remanent magnetism slope fit formula calculates each phase into.
Three-phase full-bridge converter iron core remanent magnetism calculating system provided in an embodiment of the present invention, comprising:
Acquisition module: for obtaining the saturation hysteresis loop of transformer core；
Hysteresis characteristic model foundation modeling module: for the saturation hysteresis loop using object optimizing method to transformer core
Parameter identification is carried out, transformer core hysteresis characteristic model is established；
Formula determining module: the slope for obtaining remanent magnetism and hysteresis loop according to transformer core hysteresis characteristic model closes
System；And to the relation formula of remanent magnetism and hysteresis loop slope；
Magnetic circuit model modeling module: for establishing three-phase full-bridge converter UMEC magnetic circuit model；
Calculation of residual flux module: for obtaining the positive and negative of three-phase coil after three-phase full-bridge converter iron core energizing test to be measured
To inductance value, the positive negative sense slope near remanent magnetism point is obtained according to inductance value and UMEC magnetic circuit model, further according to remanent magnetism and magnetic hysteresis
The relationship of loop line slope calculates residual induction.
Three-phase full-bridge converter iron core remanent magnetism calculating system provided by the invention, it may also is that including memory and processing
Device；
The memory is for storing instruction；
The processor according to described instruction for being operated to execute three-phase full-bridge converter iron core remanent magnetism measuring and calculating side
The step of method.
The present invention also provides a kind of computer readable storage mediums, are stored thereon with computer program, which is located
Manage the step of realizing three-phase full-bridge converter iron core remanent magnetism measuring method when device executes.
It should be understood by those skilled in the art that, embodiments herein can provide as method, system or computer program
Product.Therefore, complete hardware embodiment, complete software embodiment or reality combining software and hardware aspects can be used in the application
Apply the form of example.Moreover, it wherein includes the computer of computer usable program code that the application, which can be used in one or more,
The computer program implemented in usable storage medium (including but not limited to magnetic disk storage, CD-ROM, optical memory etc.) produces
The form of product.
The application is referring to method, the process of equipment (system) and computer program product according to the embodiment of the present application
Figure and/or block diagram describe.It should be understood that every one stream in flowchart and/or the block diagram can be realized by computer program instructions
The combination of process and/or box in journey and/or box and flowchart and/or the block diagram.It can provide these computer programs
Instruct the processor of general purpose computer, special purpose computer, Embedded Processor or other programmable data processing devices to produce
A raw machine, so that being generated by the instruction that computer or the processor of other programmable data processing devices execute for real
The device for the function of being specified in present one or more flows of the flowchart and/or one or more blocks of the block diagram.
These computer program instructions, which may also be stored in, is able to guide computer or other programmable data processing devices with spy
Determine in the computer-readable memory that mode works, so that it includes referring to that instruction stored in the computer readable memory, which generates,
Enable the manufacture of device, the command device realize in one box of one or more flows of the flowchart and/or block diagram or
The function of being specified in multiple boxes.
These computer program instructions also can be loaded onto a computer or other programmable data processing device, so that counting
Series of operation steps are executed on calculation machine or other programmable devices to generate computer implemented processing, thus in computer or
The instruction executed on other programmable devices is provided for realizing in one or more flows of the flowchart and/or block diagram one
The step of function of being specified in a box or multiple boxes.
The above is only a preferred embodiment of the present invention, it is noted that for the ordinary skill people of the art
For member, without departing from the technical principles of the invention, several improvements and modifications, these improvements and modifications can also be made
Also it should be regarded as protection scope of the present invention.
Claims (10)
1. a kind of three-phase full-bridge converter iron core remanent magnetism measuring method characterized by comprising
Obtain the saturation hysteresis loop of transformer core；
Parameter identification is carried out to the saturation hysteresis loop of transformer core, establishes transformer core hysteresis characteristic model；
The Slope relationship of remanent magnetism and hysteresis loop is obtained according to transformer core hysteresis characteristic model；And to remanent magnetism and hysteresis loop
The relation formula of slope；
Establish three-phase full-bridge converter UMEC magnetic circuit model；
Three-phase coil is positive and negative to inductance value when obtaining three-phase full-bridge converter iron core energizing test to be measured, according to inductance value with
UMEC magnetic circuit model obtains the positive negative sense slope near remanent magnetism point, calculates remanent magnetism further according to the relationship of remanent magnetism and hysteresis loop slope
Value.
2. three-phase full-bridge converter iron core remanent magnetism measuring method according to claim 1, which is characterized in that the transformer
Iron core magnetic hysteresis characteristic model is as follows:
B=μ0(M+H) (6)
He=H+ α M (7)
Wherein, M is the intensity of magnetization, and B is magnetic induction intensity, and H is magnetic field strength, μ0For space permeability, MsIt is strong for saturated magnetization
Degree, a are ideal magnetization curve form parameter, and k is magnetic hystersis loss parameter, and α coupling parameter between magnetic domain, β is model parameter, and m is
Susceptibility, ManFor anhysteretic intensity, HeFor effective magnetic field intensity, x is effectively to cut down magnetic field strength, and δ is the reaction direction B
Amount, take 1 or -1, δMThe amount for leading to non-physical solution to eliminate the direction B suddenly change and introducing, BJFor Brillouin function, J is
The quantum number of anisotropic degree is reacted, R (m) is anisotropic function；
When calculating minor loop:
A=a1=amaexp(σ1(Bs-Bmax))； (8)
α=α1=αmaexp(λ1(Bs-Bmax))； (9)
K=k1=kmaexp(-γ1(Bs-Bmax))； (10)
Wherein, ama、αma、kmaThe original value of a, α, k parameter respectively in transformer core hysteresis characteristic model；σ1、λ1、γ1For
The corrected parameter of parameter a, α, k of model, a after being improved for minor loop1、α1、k1Respectively improved for minor loop
The value of parameter a, α, k of model afterwards, Bs are the saturation value of saturation hysteresis loop, BmaxFor the saturation value of minor loop；
When calculating minor loop:
a2=a1exp(σ2(Bs-Brev)) (11)
α2=α1exp(λ2(Bs-Brev)) (12)
k2=k1exp(-γ2(Bs-Brev)) (13)
β2=βmaexp(-ξ2(Bs-Brev)) (14)
Wherein, βmaFor the original value of β parameter in transformer core hysteresis characteristic model, β2After being improved for minor loop
The value of the parameter beta of model；σ2、λ2、γ2、ξ2For parameter a, α, k, β of model after being improved for minor loop modification just
Parameter；BrevThe value of the magnetic induction density B of saturation hysteresis loop position where minor loop.
3. three-phase full-bridge converter iron core remanent magnetism measuring method according to claim 2, which is characterized in that described to transformation
The saturation hysteresis loop of device iron core carries out parameter identification
It will be saturation magnetization Ms, ideal magnetization curve form parameter a, between magnetic domain coupling parameter α, magnetic hystersis loss parameter k and
Model parameter β assigns initial value, then to test the magnetic induction density B obtainedexpAs B in transformer core hysteresis characteristic model
Input quantity finds out magnetic field strength H at this timesim, it is then found out again and tests magnetic field strength H obtainedexpBetween mean square deviationAgain with EmseFor feedback quantity control parameter Ms, a, α, k, β variation, make EmseMinimum, and root
M when accordinglys, a, α, k, β determine model, n is the H that experiment obtainsexpNumber.
4. three-phase full-bridge converter iron core remanent magnetism measuring method according to claim 2, which is characterized in that according to transformer
The relationship that iron core magnetic hysteresis characteristic model obtains remanent magnetism and hysteresis loop slope includes:
By H=H0=0, B=B0It substitutes into formula (6) and obtains the initial value M of M0, with M0, B0Respectively as in the differential equation, that is, formula (1)
The initial value of M and B, BQ=BQ-1+△B；
With the numerical solution solution formula (1) of the differential equation, dM/dB is calculated i.e.△ M, B can be acquired by acquiring in turn1=
B0+ △ B, M1=M0+ △ M is then obtained by formula (6)To obtain next point (H of hysteresis loop1,B1), together
(H can be calculated in reason2, B2)(H3, B3)……(HQ, BQ), these points are connected near as remanent magnetism point positively or negatively
Minor loop；
Wherein, H0、B0、M0Respectively magnetic field strength, magnetic induction intensity and the intensity of magnetization of remanent magnetism point, H1、B1、M1It is respectively surplus
Magnetic field strength, magnetic induction intensity and the intensity of magnetization of first point, H on the neighbouring hysteresis loop of magnetic dotQ、BQRespectively remanent magnetism point
The magnetic field strength of the Q point, magnetic induction intensity on neighbouring hysteresis loop, △ B, △ M be respectively on hysteresis loop adjacent two o'clock it
Between magnetic induction intensity and the intensity of magnetization variable quantity；
Pass through formula (BQ-B0)/(HQ-H0) remanent magnetism point (H is calculated0, B0) neighbouring minor loop slope；
By choosing different B0Value, calculates different B0The slope of the corresponding minor loop of value, can be obtained remanent magnetism
With the relationship of minor loop's slope near remanent magnetism point.
5. three-phase full-bridge converter iron core remanent magnetism measuring method according to claim 2, which is characterized in that described to remanent magnetism
Relation formula with hysteresis loop slope includes:
Fitting of a polynomial is carried out to the relationship of minor loop's slope near remanent magnetism and remanent magnetism point, obtains fitting formula:
Wherein C, D, E, F, G, I are fitting coefficient, BrFor residual induction, μrFor minor loop's slope.
6. three-phase full-bridge converter iron core remanent magnetism measuring method according to claim 1, which is characterized in that use following public affairs
Formula establishes three-phase full-bridge converter UMEC magnetic circuit model:
A=[1 1 1]T (15)
P=diag (Pa,Pb,Pc) (16)
R=P-PA (ATPA)-1ATP (17)
Lss=N2Mss (18)
Wherein, A is magnetic flux incidence matrix, and P is three-phase full-bridge converter iron core magnetic conductance matrix, Pa,Pb,PcRespectively A, B, C three-phase
Stem iron core magnetic conductance, Mss are the matrix in block form that winding coil is corresponded in matrix R, and p is the magnetic conductance of three-phase magnetic circuit, μrFor local magnetic
The slope of hysteresis curves, s are the cross-sectional area of magnetic circuit, and l is the length of magnetic circuit, and N is the coil turn of each phase winding, and Lss is winding
Equivalent inductance, r is the series resistance of circuit, and u and i are respectively the voltage and current at coil both ends, and t is the time.
7. three-phase full-bridge converter iron core remanent magnetism measuring method according to claim 1, which is characterized in that it is described obtain to
Three-phase coil is positive and negative to inductance value after survey three-phase full-bridge converter iron core energizing test, according to inductance value and UMEC magnetic circuit mould
Type obtains the positive negative sense slope near remanent magnetism point, and the relationship measuring and calculating residual induction further according to remanent magnetism and hysteresis loop slope includes:
Positive small excitation is applied to A phase coil, the voltage and current at measuring coil both ends calculates the positive inductance of A phase coil；To A
Phase coil applies the small excitation of negative sense, and the voltage and current at measuring coil both ends calculates the negative sense inductance of A phase coil；
Similarly B, C phase coil are applied positive and negative to small excitation respectively, calculates the positive inductance and negative sense inductance of B, C phase coil, with
Upper small excitation applies all in accordance with empirical value；Positive and negative by calculated A, B, C three-phase coil is updated to UMEC magnetic circuit mould to inductance
The positive and negative slope to minor loop of A, B, C three-phase is calculated in type；Further according to the relationship of remanent magnetism and hysteresis loop slope
Formula obtains each stem remanent magnetism of transformer.
8. a kind of three-phase full-bridge converter iron core remanent magnetism calculating system characterized by comprising
Acquisition module: for obtaining the saturation hysteresis loop of transformer core；
Hysteresis characteristic model foundation modeling module: parameter identification is carried out for the saturation hysteresis loop to transformer core, is established
Transformer core hysteresis characteristic model；
Formula determining module: for obtaining the Slope relationship of remanent magnetism and hysteresis loop according to transformer core hysteresis characteristic model；
And to the relation formula of remanent magnetism and hysteresis loop slope；
Magnetic circuit model modeling module: for establishing three-phase full-bridge converter UMEC magnetic circuit model；
Calculation of residual flux module: for obtaining the positive and negative to electricity of three-phase coil after three-phase full-bridge converter iron core energizing test to be measured
Inductance value obtains the positive negative sense slope near remanent magnetism point according to inductance value and UMEC magnetic circuit model, further according to remanent magnetism and hysteresis loop
The relationship of slope calculates residual induction.
9. a kind of three-phase full-bridge converter iron core remanent magnetism calculating system, which is characterized in that including memory and processor；
The memory is for storing instruction；
The processor is used to be operated according to described instruction to execute any one of according to claim 1~7 the method
Step.
10. a kind of computer readable storage medium, is stored thereon with computer program, which is characterized in that the program is by processor
The step of any one of claim 1~7 the method is realized when execution.
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