CN117590301A - Method and device for measuring core loss of magnetic control transformer - Google Patents
Method and device for measuring core loss of magnetic control transformer Download PDFInfo
- Publication number
- CN117590301A CN117590301A CN202311589721.6A CN202311589721A CN117590301A CN 117590301 A CN117590301 A CN 117590301A CN 202311589721 A CN202311589721 A CN 202311589721A CN 117590301 A CN117590301 A CN 117590301A
- Authority
- CN
- China
- Prior art keywords
- iron core
- time
- core
- loss
- flux density
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000000034 method Methods 0.000 title claims abstract description 26
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical group [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims abstract description 254
- 230000004907 flux Effects 0.000 claims abstract description 122
- 238000005259 measurement Methods 0.000 claims description 75
- 238000010586 diagram Methods 0.000 claims description 42
- 230000003068 static effect Effects 0.000 claims description 32
- 238000010276 construction Methods 0.000 claims description 31
- 229910000976 Electrical steel Inorganic materials 0.000 claims description 19
- 230000005284 excitation Effects 0.000 claims description 17
- 230000005347 demagnetization Effects 0.000 claims description 14
- 230000005415 magnetization Effects 0.000 claims description 14
- 238000004804 winding Methods 0.000 claims description 13
- 230000004069 differentiation Effects 0.000 claims description 9
- 230000000630 rising effect Effects 0.000 claims description 7
- 238000003475 lamination Methods 0.000 claims description 6
- 230000008859 change Effects 0.000 claims description 5
- 238000013461 design Methods 0.000 abstract description 6
- 230000008569 process Effects 0.000 description 10
- 230000008901 benefit Effects 0.000 description 4
- 238000012360 testing method Methods 0.000 description 4
- 230000009471 action Effects 0.000 description 3
- 229910052742 iron Inorganic materials 0.000 description 2
- 238000000691 measurement method Methods 0.000 description 2
- 230000009466 transformation Effects 0.000 description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 238000009825 accumulation Methods 0.000 description 1
- 230000000747 cardiac effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 230000010354 integration Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000035515 penetration Effects 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 230000000750 progressive effect Effects 0.000 description 1
- 238000005070 sampling Methods 0.000 description 1
Classifications
-
- 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
- G01R33/123—Measuring loss due to hysteresis
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R27/00—Arrangements for measuring resistance, reactance, impedance, or electric characteristics derived therefrom
- G01R27/02—Measuring real or complex resistance, reactance, impedance, or other two-pole characteristics derived therefrom, e.g. time constant
- G01R27/26—Measuring inductance or capacitance; Measuring quality factor, e.g. by using the resonance method; Measuring loss factor; Measuring dielectric constants ; Measuring impedance or related variables
- G01R27/2688—Measuring quality factor or dielectric loss, e.g. loss angle, or power factor
- G01R27/2694—Measuring dielectric loss, e.g. loss angle, loss factor or power factor
Abstract
The application discloses a method and a device for measuring core loss of a magnetic control transformer, wherein the method comprises the following steps: according to the circuit topology of the iron core in the magnetic control transformer, a current source equivalent circuit of an idle load equivalent circuit of the magnetic control transformer is constructed, the voltage of a controlled current source at each moment of total time is measured, the instantaneous magnetic flux density of the iron core is calculated, the hysteresis loss and the eddy current loss average value of the iron core are calculated according to the instantaneous magnetic flux density of the iron core at each moment, and the hysteresis loss and the eddy current loss average value are added to obtain the total loss value of the iron core. Therefore, the total loss value is calculated by dividing the hysteresis loss into two parts of hysteresis loss and eddy current loss, and the hysteresis loss and the eddy current loss average value are obtained by sharing a plurality of moments of the total duration, so that the accuracy of the hysteresis loss and the eddy current loss average value is higher, the accuracy of the total loss value of the iron core is higher, the design of the iron core can be more reasonable, and the overheat loss of the magnetic control transformer is effectively avoided.
Description
Technical Field
The present disclosure relates to the field of magnetic transformers, and more particularly, to a method and an apparatus for measuring core loss of a magnetic transformer.
Background
Along with the increasing demand of electric quantity, more and more new energy sources are integrated into a power grid, the high-proportion distributed new energy sources have the characteristic of large-amplitude random fluctuation, large-scale grid connection can lead to large voltage fluctuation of the power grid and difficult control, and the traditional reactive voltage regulation equipment cannot meet the rapid continuous smooth regulation demand.
The transformer is used as important power system power transformation and distribution equipment, wherein the magnetic control transformer can realize the voltage transformation function of a conventional transformer, can also play the roles of reactive compensation, current limiting and improving the power factor of the frequency converter, has the advantages of compactness and multifunction, and has remarkable effects of realizing high-efficiency control of reactive voltage, unbalance management and the like. The magnetic control transformer consists of a winding and an iron core, wherein the winding is a copper wire, the iron core is made of silicon steel sheets, and the magnetic control transformer has the advantage of small eddy current loss.
However, winding loss and core loss are inevitably and continuously generated in the operation of the magnetic control transformer, heat accumulation is caused by the loss, core heating is caused, and if the design is improper due to inaccurate loss calculation, the magnetic control transformer is likely to be overheated and damaged.
How to accurately calculate the core loss of the magnetic control transformer ensures the reasonable design of the core, avoids the overheat loss of the magnetic control transformer and is a problem needing attention.
Disclosure of Invention
In view of the above problems, the present application provides a method and an apparatus for measuring core loss of a magnetically controlled transformer, so as to ensure reasonable design of the core and avoid overheat loss of the magnetically controlled transformer.
In order to achieve the above object, the following specific solutions are proposed:
a method for measuring core loss of a magnetic control transformer comprises the following steps:
constructing a current source equivalent circuit of an empty load equivalent circuit of the magnetic control transformer according to the circuit topology of an iron core in the magnetic control transformer;
measuring the voltage of a controlled current source in the current source equivalent circuit at each moment of total measurement duration;
calculating the instantaneous magnetic flux density of the iron core at each moment of total time by using a first formula according to the voltage of the controlled current source at each moment of total time measurement, wherein the first formula is as follows:
wherein B (t) is the instantaneous magnetic flux density of the iron core at the t-th moment, u (t) is the voltage of the controlled current source at the t-th moment, N is the number of turns of windings wound on the iron core, k is the lamination coefficient, and S is the cross-sectional area of the iron core;
calculating hysteresis loss of the iron core in the total measurement time period and an average value of eddy current loss of the iron core in the total measurement time period according to the instantaneous magnetic flux density of the iron core at each time point;
And adding the hysteresis loss and the eddy current loss average value to obtain the total loss value of the iron core in the total measurement duration.
Optionally, calculating hysteresis loss of the core in the measured total duration according to the instantaneous magnetic flux density of the core at each time, including:
constructing a hysteresis loop diagram of the iron core under the total measurement duration according to the instantaneous magnetic flux density of the iron core at each moment;
determining the area of a curved surface surrounded by the hysteresis loop diagram;
according to the curved surface area, hysteresis loss of the iron core in the total measurement time length is calculated by a second formula, wherein the second formula is as follows:
wherein P is h For hysteresis loss of the core in the measured total time period, V is the volume of the core, A T And H is the magnetic field intensity of the iron core at each time point, and B is the magnetic flux density of the iron core at each time point.
Optionally, constructing a hysteresis loop diagram of the iron core under the total measurement duration according to the instantaneous magnetic flux density of the iron core at each time, including:
performing magnetic characteristic measurement on an iron core of the magnetic control transformer under a preset excitation condition to obtain a static hysteresis loop of a silicon steel sheet of the iron core, wherein the static hysteresis loop describes the change relation between the magnetic field intensity and the magnetic flux density;
Determining a magnetization curve of a rising part of the static hysteresis loop and a demagnetization curve of a falling part of the static hysteresis loop;
determining a differential result of the instantaneous magnetic flux density to time according to the instantaneous magnetic flux density of the iron core at each time, determining the magnetic field intensity corresponding to the instantaneous magnetic flux density according to the magnetization curve if the differential result is not less than 0, and determining the magnetic field intensity corresponding to the instantaneous magnetic flux density according to the demagnetization curve if the differential result is less than 0;
according to the magnetic field intensity corresponding to the instantaneous magnetic flux density of the iron core at each moment, calculating the exciting current of the iron core at the moment by using a third formula, wherein the third formula is as follows:
wherein i is L (t) is the exciting current of the iron core at the t moment, H (t) is the magnetic field intensity corresponding to the instantaneous magnetic flux density at the t moment, l e An effective magnetic path length for the core;
and constructing a hysteresis loop diagram of the iron core under the total measurement duration according to the exciting current of the iron core at each time and the voltage of the controlled current source at each time.
Optionally, constructing a hysteresis loop diagram of the iron core under the total measurement duration according to the exciting current of the iron core at each time and the voltage of the controlled current source at each time, including:
Constructing an exciting current time-varying waveform curve according to the exciting current of the iron core at each moment;
constructing a voltage time-varying waveform curve according to the voltage of the controlled current source at each moment;
determining a magnetic field intensity curve and a magnetic flux density curve of the iron core under the total measurement duration based on the exciting current time-varying waveform curve and the voltage time-varying waveform curve;
and constructing a hysteresis loop diagram of the iron core under the total measurement duration based on the magnetic field intensity curve and the magnetic flux density curve.
Optionally, calculating an average value of eddy current loss of the iron core in the total measurement duration according to the instantaneous magnetic flux density of the iron core at each time, including:
according to the instantaneous magnetic flux density of the iron core at each time, calculating the eddy current loss equivalent resistance of the iron core at the time by using a fourth formula, wherein the fourth formula is as follows:
wherein R is c (t) is the eddy current loss equivalent resistance of the iron core at the t-th moment, B s Is the saturation magnetic flux density, ρ is the silicon steel sheet density of the iron core, d is the thickness of the silicon steel sheet of the iron core, l e An effective magnetic path length for the core;
calculating the instantaneous eddy current loss of the iron core at each time point by using a fifth formula according to the eddy current loss equivalent resistance of the iron core at each time point and the voltage of the iron core at the time point, wherein the fifth formula is as follows:
Wherein i is R (t) is the instantaneous eddy current loss of the core at time t;
according to the eddy current loss equivalent resistance of the iron core at each time and the instantaneous eddy current loss of the iron core at the time, calculating the iron core eddy current loss of the iron core at the time by using a sixth formula, wherein the sixth formula is as follows:
wherein p is c (t) is core eddy current loss of the core at time t;
an eddy current loss average value of core eddy current loss of the core at each time is determined.
An iron core loss measuring device of a magnetic control transformer, comprising:
the current source equivalent circuit construction unit is used for constructing a current source equivalent circuit of an empty load equivalent circuit of the magnetic control transformer according to the circuit topology of the iron core in the magnetic control transformer;
the voltage measuring unit is used for measuring the voltage of the controlled current source in the current source equivalent circuit at each time for measuring the total duration;
the instantaneous magnetic flux density calculating unit is used for calculating the instantaneous magnetic flux density of the iron core at each moment of time according to the voltage of the controlled current source at each moment of measuring the total duration by using a first formula, wherein the first formula is as follows:
Wherein B (t) is the instantaneous magnetic flux density of the iron core at the t-th moment, u (t) is the voltage of the controlled current source at the t-th moment, N is the number of turns of windings wound on the iron core, k is the lamination coefficient, and S is the cross-sectional area of the iron core;
a hysteresis loss calculation unit for calculating hysteresis loss of the iron core in the total measurement time period according to the instantaneous magnetic flux density of the iron core at each time;
an eddy current loss average value calculation unit for calculating an eddy current loss average value of the iron core in the total measurement time period according to the instantaneous magnetic flux density of the iron core at each time;
and the core total loss value calculation unit is used for adding the hysteresis loss and the eddy current loss average value to obtain the total loss value of the core in the total measurement duration.
Optionally, the hysteresis loss calculating unit includes:
a hysteresis loop diagram construction unit, configured to construct a hysteresis loop diagram of the iron core under the total measurement duration according to the instantaneous magnetic flux density of the iron core at each time;
the curved surface area determining unit is used for determining the curved surface area surrounded by the hysteresis loop diagram;
the hysteresis loss integral calculation unit is configured to calculate, according to the curved surface area, hysteresis loss of the core in the total measurement time length by using a second formula, where the second formula is:
Wherein P is h For hysteresis loss of the core in the measured total time period, V is the volume of the core, A T And H is the magnetic field intensity of the iron core at each time point, and B is the magnetic flux density of the iron core at each time point.
Optionally, the hysteresis loop diagram building unit includes:
the magnetic control device comprises a static hysteresis loop construction unit, a magnetic control unit and a magnetic control unit, wherein the static hysteresis loop construction unit is used for measuring magnetic characteristics of an iron core of the magnetic control transformer under a preset excitation condition to obtain a static hysteresis loop of a silicon steel sheet of the iron core, and the static hysteresis loop describes a change relation between magnetic field intensity and magnetic flux density;
a curve segment dividing unit for determining a magnetization curve of a rising portion of the static hysteresis loop and a demagnetization curve of a falling portion of the static hysteresis loop;
a magnetic field strength determining unit, configured to determine, for an instantaneous magnetic flux density of the iron core at each time, a differentiation result of the instantaneous magnetic flux density with respect to time, determine a magnetic field strength corresponding to the instantaneous magnetic flux density according to the magnetization curve if the differentiation result is not less than 0, and determine a magnetic field strength corresponding to the instantaneous magnetic flux density according to the demagnetization curve if the differentiation result is less than 0;
The exciting current calculating unit is used for calculating the exciting current of the iron core at each moment by using a third formula according to the magnetic field intensity corresponding to the instantaneous magnetic flux density of the iron core at each moment, and the third formula is as follows:
wherein i is L (t) is the exciting current of the iron core at the t moment, H (t) is the magnetic field intensity corresponding to the instantaneous magnetic flux density at the t moment, l e An effective magnetic path length for the core;
and the current-voltage hysteresis loop construction unit is used for constructing a hysteresis loop diagram of the iron core under the total measurement duration according to the exciting current of the iron core at each time and the voltage of the controlled current source at each time.
Optionally, the current-voltage hysteresis loop construction unit includes:
a current waveform construction unit, configured to construct an excitation current time-varying waveform curve according to the excitation current of the iron core at each time;
the voltage waveform construction unit is used for constructing a voltage time-varying waveform curve according to the voltages of the controlled current source at each moment;
the intensity density curve construction unit is used for determining a magnetic field intensity curve and a magnetic flux density curve of the iron core under the total measurement duration based on the exciting current time-varying waveform curve and the voltage time-varying waveform curve;
And the intensity density hysteresis loop construction unit is used for constructing a hysteresis loop diagram of the iron core under the total measurement duration based on the magnetic field intensity curve and the magnetic flux density curve.
Optionally, the eddy current loss average value calculating unit includes:
an eddy current loss equivalent resistance calculation unit, configured to calculate, according to an instantaneous magnetic flux density of the core at each time, an eddy current loss equivalent resistance of the core at the time by using a fourth formula, where the fourth formula is:
wherein R is c (t) is the eddy current loss equivalent resistance of the iron core at the t-th moment, B s Is the saturation magnetic flux density, ρ is the silicon steel sheet density of the iron core, d is the thickness of the silicon steel sheet of the iron core, l e An effective magnetic path length for the core;
an instantaneous eddy current loss calculation unit, configured to calculate, according to an eddy current loss equivalent resistance of the core at each time and a voltage of the core at the time, an instantaneous eddy current loss of the core at the time using a fifth formula, where the fifth formula is:
wherein i is R (t) is the instantaneous eddy current loss of the core at time t;
an iron core eddy current loss calculation unit, configured to calculate, according to an eddy current loss equivalent resistance of the iron core at each time and an instantaneous eddy current loss of the iron core at the time, an iron core eddy current loss of the iron core at the time by using a sixth formula, where the sixth formula is:
Wherein p is c (t) is core eddy current loss of the core at time t;
an eddy current loss average value determining unit for determining an eddy current loss average value of core eddy current loss of the core at each time.
By means of the technical scheme, the current source equivalent circuit of the no-load equivalent circuit of the magnetic control transformer is constructed according to the circuit topology of the iron core in the magnetic control transformer, the voltage of the controlled current source in the current source equivalent circuit at each time of the total measurement time is measured, the instantaneous magnetic flux density of the iron core at each time is calculated according to the voltage of the controlled current source at each time of the total measurement time, the hysteresis loss of the iron core in the total measurement time is calculated according to the instantaneous magnetic flux density of the iron core at each time, the average value of the eddy current loss of the iron core in the total measurement time is calculated, and the hysteresis loss and the average value of the eddy current loss are added to obtain the total loss value of the iron core in the total measurement time. Therefore, the total loss value of the iron core is calculated by dividing the total loss value into two parts, namely hysteresis loss and eddy current loss, and the hysteresis loss and the eddy current loss average value are obtained through analysis at a plurality of moments of total time measurement, so that the accuracy of the hysteresis loss and the eddy current loss average value is higher, the accuracy of the total loss value of the iron core is higher, the design of the iron core can be more reasonable, and the overheat loss of the magnetic control transformer is effectively avoided.
Drawings
Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the application. Also, like reference numerals are used to designate like parts throughout the figures. In the drawings:
fig. 1 is a schematic flow chart for implementing core loss measurement of a magnetically controlled transformer according to an embodiment of the present disclosure;
fig. 2 is an equivalent circuit diagram of the magnetic control transformer provided in the embodiment of the present application when no load exists;
fig. 3 is a current source equivalent circuit of a magnetic control transformer according to an embodiment of the present application;
fig. 4 is a schematic structural diagram of a device for implementing core loss measurement of a magnetically controlled transformer according to an embodiment of the present application.
Detailed Description
The following description of the embodiments of the present application will be made clearly and fully with reference to the accompanying drawings, in which it is evident that the embodiments described are only some, but not all, of the embodiments of the present application. All other embodiments, which can be made by one of ordinary skill in the art without undue burden from the present disclosure, are within the scope of the present disclosure.
The scheme can be realized based on the terminal with the data processing capability, and the terminal can be a mobile phone, a computer, a cloud terminal, a server and the like.
Next, as described in connection with fig. 1, the core loss measurement method of the magnetic control transformer of the present application may include the following steps:
and S110, constructing a current source equivalent circuit of an empty load equivalent circuit of the magnetic control transformer according to the circuit topology of the iron core in the magnetic control transformer.
The no-load equivalent circuit of the magnetic control transformer can represent the equivalent circuit of the magnetic control transformer when no-load is performed. The equivalent circuit diagram of the magnetic control transformer in no-load is shown in figure 2, L 0 Winding air core inductance for winding around iron core, R 0 In order to wind the winding equivalent resistance of the winding of the iron core, L (t) is the equivalent inductance of the iron core at the t-th moment, R C (t) is the eddy current loss equivalent resistance of the iron core at the t-th moment, i L (t) is the current flowing through the equivalent inductor at the time t, i R And (t) is a current flowing through the eddy current loss equivalent resistance at the time t, and u (t) is a voltage across the core. As can be seen from FIG. 2, the voltage u (t) across the core is equal to the voltage across L (t), and is also equal to R C (t) the voltage across.
Further, a voltage source is arranged, the voltage source is connected in series with a loop equivalent resistor representing a wire resistor and then is connected with a parallel branch, and a controlled current source reflecting an equivalent inductance in the parallel branch is connected with a controlled current source reflecting an eddy current loss equivalent resistor in parallel, so that a current source equivalent circuit of the no-load equivalent circuit is obtained. The current source equivalent circuit is shown in fig. 3, 1 in fig. 3 represents an excitation power supply, 2 in fig. 3 represents a test loop equivalent resistance, 3 in fig. 3 represents a controlled current source reflecting an equivalent inductance, and 4 in fig. 3 represents a controlled current source reflecting an eddy current loss equivalent resistance.
Step S120, measuring the voltage of the controlled current source in the current source equivalent circuit at each moment of measuring the total duration.
Specifically, the measured total duration may represent a single test period, which may be pre-marked with a plurality of time points, and the voltage u (t) of the controlled current source may be collected once each time the marked time point is reached.
Step S130, calculating the instantaneous magnetic flux density of the iron core at each moment of the total time length according to the voltage of the controlled current source at the moment of measuring the total time length by using a first formula.
Wherein, the first formula may be:
wherein B (t) is the instantaneous magnetic flux density of the iron core at the t-th moment, u (t) is the voltage of the controlled current source at the t-th moment, N is the number of winding turns wound on the iron core, k is the lamination coefficient, and S is the cross-sectional area of the iron core.
Step S140, calculating hysteresis loss of the iron core in the total measurement time period and eddy current loss average value of the iron core in the total measurement time period according to the instantaneous magnetic flux density of the iron core at each time.
And step S150, adding the hysteresis loss and the eddy current loss average value to obtain the total loss value of the iron core in the total measurement duration.
It will be appreciated that the total loss of the core consists of hysteresis loss and eddy current loss, and therefore the average of the hysteresis loss and eddy current loss can be added to obtain the total loss value of the core during the total length of time measured.
According to the iron core loss measurement method of the magnetic control transformer, a current source equivalent circuit of an idle equivalent circuit of the magnetic control transformer is constructed according to the circuit topology of an iron core in the magnetic control transformer, the voltage of a controlled current source in the current source equivalent circuit at each time of total measurement duration is measured, the instantaneous magnetic flux density of the iron core at each time is calculated according to the voltage of the controlled current source at each time of total measurement duration, the hysteresis loss of the iron core in the total measurement duration is calculated according to the instantaneous magnetic flux density of the iron core at each time, and the average value of eddy current loss of the iron core in the total measurement duration is added to obtain the total loss value of the iron core in the total measurement duration. Therefore, the total loss value of the iron core is calculated by dividing the total loss value into two parts, namely hysteresis loss and eddy current loss, and the hysteresis loss and the eddy current loss average value are obtained through analysis at a plurality of moments of total time measurement, so that the accuracy of the hysteresis loss and the eddy current loss average value is higher, the accuracy of the total loss value of the iron core is higher, the design of the iron core can be more reasonable, and the overheat loss of the magnetic control transformer is effectively avoided.
In some embodiments of the present application, a process for calculating hysteresis loss of a core in measuring a total duration according to an instantaneous magnetic flux density of the core at each time, which is mentioned in the above embodiments, is described, and the process may include:
s1, constructing a hysteresis loop diagram of the iron core under the condition of measuring the total duration according to the instantaneous magnetic flux density of the iron core at each moment.
Specifically, the process of constructing the hysteresis loop diagram of the iron core under the measurement total duration according to the instantaneous magnetic flux density of the iron core at each time may include:
s11, carrying out magnetic characteristic measurement on the iron core of the magnetic control transformer under the preset excitation condition to obtain a static hysteresis loop of the silicon steel sheet of the iron core.
Specifically, the preset excitation condition may be a direct current excitation condition or an excitation condition of a 5Hz sine wave.
It will be appreciated that the static hysteresis loop describes the relationship between the magnetic field strength and the magnetic flux density.
S12, determining a magnetization curve of the rising part of the static hysteresis loop and a demagnetization curve of the falling part of the static hysteresis loop.
Specifically, the curve of the rising portion of the static hysteresis loop may be recorded as a magnetization curve, and the magnetization curve may be temporarily stored in table 1 for inquiring the corresponding magnetic field intensity according to the specified magnetic field intensity or inquiring the corresponding magnetic field intensity according to the specified magnetic field intensity.
The curve of the falling portion in the static hysteresis loop may be noted as a demagnetization curve, and the demagnetization curve may be temporarily stored in table 2 for querying the corresponding magnetic field strength according to the specified magnetic field density or querying the corresponding magnetic field density according to the specified magnetic field strength.
S13, determining a differential result of the instantaneous magnetic flux density to the time according to the instantaneous magnetic flux density of the iron core at each time, determining the magnetic field intensity corresponding to the instantaneous magnetic flux density according to a magnetization curve if the differential result is not less than 0, and determining the magnetic field intensity corresponding to the instantaneous magnetic flux density according to a demagnetization curve if the differential result is less than 0.
S14, calculating the exciting current of the iron core at each moment according to the magnetic field intensity corresponding to the instantaneous magnetic flux density of the iron core at each moment.
S15, constructing a hysteresis loop diagram of the iron core under the condition of measuring the total duration according to the exciting current of the iron core at each time and the voltage of the controlled current source at each time.
Specifically, according to the exciting current of the iron core at each time and the voltage of the controlled current source at each time, the process of constructing the hysteresis loop diagram of the iron core under the total measurement duration may include:
S151, constructing an exciting current time-varying waveform curve according to exciting currents of the iron core at all times.
S152, constructing a voltage time-varying waveform curve according to the voltage of the controlled current source at each moment.
S153, determining a magnetic field intensity curve and a magnetic flux density curve of the iron core under the total measurement duration based on the exciting current time-varying waveform curve and the voltage time-varying waveform curve.
S154, constructing a hysteresis loop diagram of the iron core under the condition of measuring the total duration based on the magnetic field intensity curve and the magnetic flux density curve.
It can be understood that, since the voltage value of the voltage source is time-varying, the instantaneous values of all the dynamic parameters are different at each moment, the parameters are mutually coupled and mutually affected, the current waveform and the voltage waveform can be measured by continuous sampling, then the magnetic field intensity curve and the magnetic flux density curve are obtained, and the magnetic field intensity is taken as an abscissa and the magnetic flux density is taken as an ordinate, so that the hysteresis loop diagram is constructed.
S2, determining the area of a curved surface surrounded by the hysteresis loop diagram.
Specifically, the curved surface defined by the hysteresis loop of the hysteresis loop diagram can be denoted as A T 。
S3, calculating hysteresis loss of the iron core in the total measurement time length by using a second formula according to the curved surface area.
Wherein, the second formula may be:
wherein P is h For hysteresis loss of the core in the measured total time period, V is the volume of the core, A T And H is the magnetic field intensity of the iron core at each time point, and B is the magnetic flux density of the iron core at each time point.
It can be appreciated that for curved surface A T And (3) carrying out area integration to obtain the average value of hysteresis loss of the unit volume of the iron core in one test period or the total measurement time period, and multiplying the average value of hysteresis loss of the unit volume by the volume V of the iron core, so that the hysteresis loss of the whole iron core in the total measurement time period can be obtained.
In some embodiments of the present application, a process for calculating an exciting current of the core at each time point according to a magnetic field strength corresponding to an instantaneous magnetic flux density of the core at the time point, which is described in the foregoing embodiments, may include:
and calculating the exciting current of the iron core at each moment by using a third formula according to the magnetic field intensity corresponding to the instantaneous magnetic flux density of the iron core at each moment.
Wherein, the third formula may be:
wherein i is L (t) is the exciting current of the iron core at the t moment, H (t) is the magnetic field intensity corresponding to the instantaneous magnetic flux density at the t moment, l e Is the effective magnetic path length of the core.
It is understood that the third formula can be established by ampere loop law under the equivalent circuit of the no-load magnetic control transformer, and can reflect the relationship between the magnetic field strength and the exciting current.
In some embodiments of the present application, a process for calculating an average value of eddy current loss of the core in a total measurement period according to the instantaneous magnetic flux density of the core at each time mentioned in the above embodiments is described, where the process may include:
s1, calculating the eddy current loss equivalent resistance of the iron core at each moment by using a fourth formula according to the instantaneous magnetic flux density of the iron core at each moment.
Wherein, the fourth formula may be:
wherein R is c (t) is the eddy current loss equivalent resistance of the iron core at the t-th moment, B s Is the saturation magnetic flux density, ρ is the silicon steel sheet density of the iron core, d is the thickness of the silicon steel sheet of the iron core, l e Is the effective magnetic path length of the core.
It can be understood that the fourth formula is the eddy current loss equivalent resistance R obtained according to the wave penetration theory c (t) a function related to the magnetic flux density B (t).
S2, calculating the instantaneous eddy current loss of the iron core at each moment by using a fifth formula according to the eddy current loss equivalent resistance of the iron core at each moment and the voltage of the iron core at the moment.
Wherein, the fifth formula may be:
wherein i is R And (t) is the instantaneous eddy current loss of the iron core at the t-th moment.
Specifically, the instantaneous eddy current loss i of the core at the t-th time R (t) the output current of a controlled current source reflecting the eddy current loss equivalent resistance can be characterized.
S3, calculating the core eddy current loss of the core at each time by using a sixth formula according to the eddy current loss equivalent resistance of the core at each time and the instantaneous eddy current loss of the core at the time.
Wherein, the sixth formula may be:
wherein p is c And (t) is the core eddy current loss of the core at the t-th moment.
It will be appreciated that the sixth equation is constructed in a mode that absorbs electrical power over the eddy current resistance.
S4, determining an eddy current loss average value of the core eddy current loss of the core at each time.
Specifically, the eddy current loss average value of the core eddy current loss at each time of the core can be determined using the following formula:
wherein P is c Iron for iron core at each momentThe eddy current loss average of the cardiac eddy current loss, T, is the total length of measurement or a single test period.
The device for measuring the core loss of the magnetic control transformer provided in the embodiment of the application is described below, and the device for measuring the core loss of the magnetic control transformer described below and the method for measuring the core loss of the magnetic control transformer described above can be referred to correspondingly.
Referring to fig. 4, fig. 4 is a schematic structural diagram of an apparatus for implementing core loss measurement of a magnetically controlled transformer according to an embodiment of the present disclosure.
As shown in fig. 4, the apparatus may include:
a current source equivalent circuit construction unit 11, configured to construct a current source equivalent circuit of an empty load equivalent circuit of a magnetic control transformer according to a circuit topology of an iron core in the magnetic control transformer;
a voltage measurement unit 12 for measuring the voltage of the controlled current source in the current source equivalent circuit at each time of measuring the total duration;
an instantaneous magnetic flux density calculating unit 13, configured to calculate, according to the voltage of the controlled current source at each time point when the total duration is measured, the instantaneous magnetic flux density of the core at the time point by using a first formula, where the first formula is:
wherein B (t) is the instantaneous magnetic flux density of the iron core at the t-th moment, u (t) is the voltage of the controlled current source at the t-th moment, N is the number of turns of windings wound on the iron core, k is the lamination coefficient, and S is the cross-sectional area of the iron core;
a hysteresis loss calculation unit 14 for calculating hysteresis loss of the core in the measured total time period from the instantaneous magnetic flux density of the core at each time point;
An eddy current loss average value calculation unit 15 for calculating an eddy current loss average value of the iron core in the measured total time period based on the instantaneous magnetic flux density of the iron core at each time;
and a core total loss value calculation unit 16 for adding the hysteresis loss and the eddy current loss average value to obtain a total loss value of the core in the measured total time period.
Optionally, the hysteresis loss calculating unit includes:
a hysteresis loop diagram construction unit, configured to construct a hysteresis loop diagram of the iron core under the total measurement duration according to the instantaneous magnetic flux density of the iron core at each time;
the curved surface area determining unit is used for determining the curved surface area surrounded by the hysteresis loop diagram;
the hysteresis loss integral calculation unit is configured to calculate, according to the curved surface area, hysteresis loss of the core in the total measurement time length by using a second formula, where the second formula is:
wherein P is h For hysteresis loss of the core in the measured total time period, V is the volume of the core, A T And H is the magnetic field intensity of the iron core at each time point, and B is the magnetic flux density of the iron core at each time point.
Optionally, the hysteresis loop diagram building unit includes:
the magnetic control device comprises a static hysteresis loop construction unit, a magnetic control unit and a magnetic control unit, wherein the static hysteresis loop construction unit is used for measuring magnetic characteristics of an iron core of the magnetic control transformer under a preset excitation condition to obtain a static hysteresis loop of a silicon steel sheet of the iron core, and the static hysteresis loop describes a change relation between magnetic field intensity and magnetic flux density;
a curve segment dividing unit for determining a magnetization curve of a rising portion of the static hysteresis loop and a demagnetization curve of a falling portion of the static hysteresis loop;
a magnetic field strength determining unit, configured to determine, for an instantaneous magnetic flux density of the iron core at each time, a differentiation result of the instantaneous magnetic flux density with respect to time, determine a magnetic field strength corresponding to the instantaneous magnetic flux density according to the magnetization curve if the differentiation result is not less than 0, and determine a magnetic field strength corresponding to the instantaneous magnetic flux density according to the demagnetization curve if the differentiation result is less than 0;
the exciting current calculating unit is used for calculating the exciting current of the iron core at each moment by using a third formula according to the magnetic field intensity corresponding to the instantaneous magnetic flux density of the iron core at each moment, and the third formula is as follows:
Wherein i is L (t) is the exciting current of the iron core at the t moment, H (t) is the magnetic field intensity corresponding to the instantaneous magnetic flux density at the t moment, l e An effective magnetic path length for the core;
and the current-voltage hysteresis loop construction unit is used for constructing a hysteresis loop diagram of the iron core under the total measurement duration according to the exciting current of the iron core at each time and the voltage of the controlled current source at each time.
Optionally, the current-voltage hysteresis loop construction unit includes:
a current waveform construction unit, configured to construct an excitation current time-varying waveform curve according to the excitation current of the iron core at each time;
the voltage waveform construction unit is used for constructing a voltage time-varying waveform curve according to the voltages of the controlled current source at each moment;
the intensity density curve construction unit is used for determining a magnetic field intensity curve and a magnetic flux density curve of the iron core under the total measurement duration based on the exciting current time-varying waveform curve and the voltage time-varying waveform curve;
and the intensity density hysteresis loop construction unit is used for constructing a hysteresis loop diagram of the iron core under the total measurement duration based on the magnetic field intensity curve and the magnetic flux density curve.
Optionally, the eddy current loss average value calculating unit includes:
an eddy current loss equivalent resistance calculation unit, configured to calculate, according to an instantaneous magnetic flux density of the core at each time, an eddy current loss equivalent resistance of the core at the time by using a fourth formula, where the fourth formula is:
wherein R is c (t) is the eddy current loss equivalent resistance of the iron core at the t-th moment, B s Is the saturation magnetic flux density, ρ is the silicon steel sheet density of the iron core, d is the thickness of the silicon steel sheet of the iron core, l e An effective magnetic path length for the core;
an instantaneous eddy current loss calculation unit, configured to calculate, according to an eddy current loss equivalent resistance of the core at each time and a voltage of the core at the time, an instantaneous eddy current loss of the core at the time using a fifth formula, where the fifth formula is:
wherein i is R (t) is the instantaneous eddy current loss of the core at time t;
an iron core eddy current loss calculation unit, configured to calculate, according to an eddy current loss equivalent resistance of the iron core at each time and an instantaneous eddy current loss of the iron core at the time, an iron core eddy current loss of the iron core at the time by using a sixth formula, where the sixth formula is:
Wherein p is c (t) is the iron of the iron core at the t-th momentHeart eddy current loss;
an eddy current loss average value determining unit for determining an eddy current loss average value of core eddy current loss of the core at each time.
Finally, it is further noted that relational terms such as first and second, and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.
In the present specification, each embodiment is described in a progressive manner, and each embodiment focuses on the difference from other embodiments, and may be combined according to needs, and the same similar parts may be referred to each other.
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the application. Thus, the present application is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims (10)
1. A method for measuring core loss of a magnetically controlled transformer, comprising:
constructing a current source equivalent circuit of an empty load equivalent circuit of the magnetic control transformer according to the circuit topology of an iron core in the magnetic control transformer;
measuring the voltage of a controlled current source in the current source equivalent circuit at each moment of total measurement duration;
calculating the instantaneous magnetic flux density of the iron core at each moment of total time by using a first formula according to the voltage of the controlled current source at each moment of total time measurement, wherein the first formula is as follows:
wherein B (t) is the instantaneous magnetic flux density of the iron core at the t-th moment, u (t) is the voltage of the controlled current source at the t-th moment, N is the number of turns of windings wound on the iron core, k is the lamination coefficient, and S is the cross-sectional area of the iron core;
Calculating hysteresis loss of the iron core in the total measurement time period and an average value of eddy current loss of the iron core in the total measurement time period according to the instantaneous magnetic flux density of the iron core at each time point;
and adding the hysteresis loss and the eddy current loss average value to obtain the total loss value of the iron core in the total measurement duration.
2. The method of claim 1, wherein calculating hysteresis loss of the core for the measured total length of time based on the instantaneous magnetic flux density of the core at each time instant, comprises:
constructing a hysteresis loop diagram of the iron core under the total measurement duration according to the instantaneous magnetic flux density of the iron core at each moment;
determining the area of a curved surface surrounded by the hysteresis loop diagram;
according to the curved surface area, hysteresis loss of the iron core in the total measurement time length is calculated by a second formula, wherein the second formula is as follows:
wherein P is h For hysteresis loss of the core in the measured total time period, V is the volume of the core, A T And H is the magnetic field intensity of the iron core at each time point, and B is the magnetic flux density of the iron core at each time point.
3. The method of claim 2, wherein constructing a hysteresis loop diagram of the core at the measured total time period from the instantaneous magnetic flux density of the core at each time instant comprises:
performing magnetic characteristic measurement on an iron core of the magnetic control transformer under a preset excitation condition to obtain a static hysteresis loop of a silicon steel sheet of the iron core, wherein the static hysteresis loop describes the change relation between the magnetic field intensity and the magnetic flux density;
determining a magnetization curve of a rising part of the static hysteresis loop and a demagnetization curve of a falling part of the static hysteresis loop;
determining a differential result of the instantaneous magnetic flux density to time according to the instantaneous magnetic flux density of the iron core at each time, determining the magnetic field intensity corresponding to the instantaneous magnetic flux density according to the magnetization curve if the differential result is not less than 0, and determining the magnetic field intensity corresponding to the instantaneous magnetic flux density according to the demagnetization curve if the differential result is less than 0;
according to the magnetic field intensity corresponding to the instantaneous magnetic flux density of the iron core at each moment, calculating the exciting current of the iron core at the moment by using a third formula, wherein the third formula is as follows:
Wherein i is L (t) is the exciting current of the iron core at the t moment, and H (t) is the t momentThe magnetic field strength corresponding to the instantaneous magnetic flux density l e An effective magnetic path length for the core;
and constructing a hysteresis loop diagram of the iron core under the total measurement duration according to the exciting current of the iron core at each time and the voltage of the controlled current source at each time.
4. A method according to claim 3, wherein constructing a hysteresis loop diagram of the core at the measured total time period from the excitation current of the core at each time instant and the voltage of the controlled current source at each time instant comprises:
constructing an exciting current time-varying waveform curve according to the exciting current of the iron core at each moment;
constructing a voltage time-varying waveform curve according to the voltage of the controlled current source at each moment;
determining a magnetic field intensity curve and a magnetic flux density curve of the iron core under the total measurement duration based on the exciting current time-varying waveform curve and the voltage time-varying waveform curve;
and constructing a hysteresis loop diagram of the iron core under the total measurement duration based on the magnetic field intensity curve and the magnetic flux density curve.
5. The method of claim 1, wherein calculating an average value of eddy current losses of the core over the measured total length of time based on the instantaneous magnetic flux density of the core at each time instant, comprises:
according to the instantaneous magnetic flux density of the iron core at each time, calculating the eddy current loss equivalent resistance of the iron core at the time by using a fourth formula, wherein the fourth formula is as follows:
wherein R is c (t) is the eddy current loss of the iron core at the t-th momentConsumption equivalent resistance, B s Is the saturation magnetic flux density, ρ is the silicon steel sheet density of the iron core, d is the thickness of the silicon steel sheet of the iron core, l e An effective magnetic path length for the core;
calculating the instantaneous eddy current loss of the iron core at each time point by using a fifth formula according to the eddy current loss equivalent resistance of the iron core at each time point and the voltage of the iron core at the time point, wherein the fifth formula is as follows:
wherein i is R (t) is the instantaneous eddy current loss of the core at time t;
according to the eddy current loss equivalent resistance of the iron core at each time and the instantaneous eddy current loss of the iron core at the time, calculating the iron core eddy current loss of the iron core at the time by using a sixth formula, wherein the sixth formula is as follows:
Wherein p is c (t) is core eddy current loss of the core at time t;
an eddy current loss average value of core eddy current loss of the core at each time is determined.
6. A core loss measurement apparatus for a magnetically controlled transformer, comprising:
the current source equivalent circuit construction unit is used for constructing a current source equivalent circuit of an empty load equivalent circuit of the magnetic control transformer according to the circuit topology of the iron core in the magnetic control transformer;
the voltage measuring unit is used for measuring the voltage of the controlled current source in the current source equivalent circuit at each time for measuring the total duration;
the instantaneous magnetic flux density calculating unit is used for calculating the instantaneous magnetic flux density of the iron core at each moment of time according to the voltage of the controlled current source at each moment of measuring the total duration by using a first formula, wherein the first formula is as follows:
wherein B (t) is the instantaneous magnetic flux density of the iron core at the t-th moment, u (t) is the voltage of the controlled current source at the t-th moment, N is the number of turns of windings wound on the iron core, k is the lamination coefficient, and S is the cross-sectional area of the iron core;
a hysteresis loss calculation unit for calculating hysteresis loss of the iron core in the total measurement time period according to the instantaneous magnetic flux density of the iron core at each time;
An eddy current loss average value calculation unit for calculating an eddy current loss average value of the iron core in the total measurement time period according to the instantaneous magnetic flux density of the iron core at each time;
and the core total loss value calculation unit is used for adding the hysteresis loss and the eddy current loss average value to obtain the total loss value of the core in the total measurement duration.
7. The apparatus according to claim 6, wherein the hysteresis loss calculating unit includes:
a hysteresis loop diagram construction unit, configured to construct a hysteresis loop diagram of the iron core under the total measurement duration according to the instantaneous magnetic flux density of the iron core at each time;
the curved surface area determining unit is used for determining the curved surface area surrounded by the hysteresis loop diagram;
the hysteresis loss integral calculation unit is configured to calculate, according to the curved surface area, hysteresis loss of the core in the total measurement time length by using a second formula, where the second formula is:
wherein P is h For hysteresis loss of the core in the measured total time period, V is the volume of the core, A T And H is the magnetic field intensity of the iron core at each time point, and B is the magnetic flux density of the iron core at each time point.
8. The apparatus of claim 7, wherein the hysteresis loop diagram construction unit includes:
the magnetic control device comprises a static hysteresis loop construction unit, a magnetic control unit and a magnetic control unit, wherein the static hysteresis loop construction unit is used for measuring magnetic characteristics of an iron core of the magnetic control transformer under a preset excitation condition to obtain a static hysteresis loop of a silicon steel sheet of the iron core, and the static hysteresis loop describes a change relation between magnetic field intensity and magnetic flux density;
a curve segment dividing unit for determining a magnetization curve of a rising portion of the static hysteresis loop and a demagnetization curve of a falling portion of the static hysteresis loop;
a magnetic field strength determining unit, configured to determine, for an instantaneous magnetic flux density of the iron core at each time, a differentiation result of the instantaneous magnetic flux density with respect to time, determine a magnetic field strength corresponding to the instantaneous magnetic flux density according to the magnetization curve if the differentiation result is not less than 0, and determine a magnetic field strength corresponding to the instantaneous magnetic flux density according to the demagnetization curve if the differentiation result is less than 0;
the exciting current calculating unit is used for calculating the exciting current of the iron core at each moment by using a third formula according to the magnetic field intensity corresponding to the instantaneous magnetic flux density of the iron core at each moment, and the third formula is as follows:
Wherein i is L (t) is the exciting current of the iron core at the t-th moment, H (t)A magnetic field intensity corresponding to the instantaneous magnetic flux density at the t-th moment l e An effective magnetic path length for the core;
and the current-voltage hysteresis loop construction unit is used for constructing a hysteresis loop diagram of the iron core under the total measurement duration according to the exciting current of the iron core at each time and the voltage of the controlled current source at each time.
9. The apparatus of claim 8, wherein the current-voltage hysteresis loop construction unit includes:
a current waveform construction unit, configured to construct an excitation current time-varying waveform curve according to the excitation current of the iron core at each time;
the voltage waveform construction unit is used for constructing a voltage time-varying waveform curve according to the voltages of the controlled current source at each moment;
the intensity density curve construction unit is used for determining a magnetic field intensity curve and a magnetic flux density curve of the iron core under the total measurement duration based on the exciting current time-varying waveform curve and the voltage time-varying waveform curve;
and the intensity density hysteresis loop construction unit is used for constructing a hysteresis loop diagram of the iron core under the total measurement duration based on the magnetic field intensity curve and the magnetic flux density curve.
10. The apparatus according to claim 6, wherein the eddy current loss average calculation unit includes:
an eddy current loss equivalent resistance calculation unit, configured to calculate, according to an instantaneous magnetic flux density of the core at each time, an eddy current loss equivalent resistance of the core at the time by using a fourth formula, where the fourth formula is:
wherein R is c (t) is the ironEddy current loss equivalent resistance of heart at t-th moment, B s Is the saturation magnetic flux density, ρ is the silicon steel sheet density of the iron core, d is the thickness of the silicon steel sheet of the iron core, l e An effective magnetic path length for the core;
an instantaneous eddy current loss calculation unit, configured to calculate, according to an eddy current loss equivalent resistance of the core at each time and a voltage of the core at the time, an instantaneous eddy current loss of the core at the time using a fifth formula, where the fifth formula is:
wherein i is R (t) is the instantaneous eddy current loss of the core at time t;
an iron core eddy current loss calculation unit, configured to calculate, according to an eddy current loss equivalent resistance of the iron core at each time and an instantaneous eddy current loss of the iron core at the time, an iron core eddy current loss of the iron core at the time by using a sixth formula, where the sixth formula is:
Wherein p is c (t) is core eddy current loss of the core at time t;
an eddy current loss average value determining unit for determining an eddy current loss average value of core eddy current loss of the core at each time.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311589721.6A CN117590301A (en) | 2023-11-24 | 2023-11-24 | Method and device for measuring core loss of magnetic control transformer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311589721.6A CN117590301A (en) | 2023-11-24 | 2023-11-24 | Method and device for measuring core loss of magnetic control transformer |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN117590301A true CN117590301A (en) | 2024-02-23 |
Family
ID=89909563
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202311589721.6A Pending CN117590301A (en) | 2023-11-24 | 2023-11-24 | Method and device for measuring core loss of magnetic control transformer |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117590301A (en) |
-
2023
- 2023-11-24 CN CN202311589721.6A patent/CN117590301A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Krings et al. | Temperature influence of NiFe steel laminations on the characteristics of small slotless permanent magnet machines | |
| CN111914413B (en) | Magnetic core high-frequency loss calculation method under symmetrical/asymmetrical rectangular voltage excitation | |
| CN107703368B (en) | Method for measuring inductance of transformer in deep saturation state | |
| CN113283073B (en) | Multi-objective optimization design method for three-phase high-frequency high-power transformer | |
| JP2004508703A (en) | Manufacturing method of inductor | |
| Fu et al. | Calculation and analysis of iron loss in homopolar inductor alternator | |
| Umetani et al. | Simple fully analytical copper loss model of litz wire made of strands twisted in multiple levels | |
| Kefalas et al. | Mixed Si-Fe wound cores five legged transformer: losses and flux distribution analysis | |
| CN117590301A (en) | Method and device for measuring core loss of magnetic control transformer | |
| Zhai et al. | Modeling and characteristics investigation of self-regulating HTS flux pump | |
| Wrobel et al. | Scaling of AC copper loss in thermal modeling of electrical machines | |
| Sato et al. | Study on an accurate iron loss calculation method considering the non-uniformity of the magnetic flux density | |
| CN106680744A (en) | Method for analyzing ferromagnetic features of sensing electricity taking device of high tension transmission line | |
| Yazdani-Asrami et al. | Experimental investigation for power loss measurement of superconducting coils under harmonic supply current | |
| CN114242433B (en) | Multi-objective optimization design method for three-phase three-dimensional coiled core transformer excited by PWM voltage | |
| Liu et al. | Design and optimization of high frequency transformer with nanocrystalline core | |
| Lee et al. | Experimental and numerical analysis of a simple core loss calculation for AC filter inductor in PWM DC-AC inverters | |
| Utschick et al. | AC Loss Behavior of Wireless Power Transfer Coils | |
| Mauger et al. | Core losses of nanocrystalline materials under DC bias conditions | |
| Lee et al. | Characteristics of a continuous disk winding for large power HTS transformer | |
| Lee et al. | Comparison of AC losses of HTS pancake winding with single tape and multi-stacked tape | |
| Nakazaki et al. | Iron loss properties of a practical rotating machine stator core at each manufacturing stage | |
| Chen et al. | Research on dynamic magnetic flux measurement under DC-biased magnetization by the type-c transducer | |
| Acero et al. | A model of the equivalent impedance of the coupled winding-load system for a domestic induction heating application | |
| CN218003561U (en) | Transformer core loss measuring device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |