CN116738139B - Method for predicting DC magnetic bias transient eddy current loss of transformer - Google Patents
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Abstract
The invention relates to the technical field of data processing, in particular to a method for predicting DC magnetic bias transient eddy current loss of a transformer, which comprises the following steps: collecting various data in a transformer; taking the temperature average value of the silicon steel sheet in the transformer as the integral temperature of the transformer, drawing a change curve of the integral temperature of the transformer along with time, and combining a time sequence of the change of the power of the transformer to obtain a temperature hysteresis influence interval of the transformer; acquiring a temperature difference coefficient of the transformer through the acquired temperature data in the transformer; acquiring power parameters of the transformer through the acquired power data of the transformer; and obtaining the magnetic bias degree of the transformer through the power parameter and the temperature difference coefficient of the transformer. And predicting the magnetic bias degree of the temperature hysteresis influence interval of the transformer according to the magnetic bias degree of the transformer. And adjusting the operating power of the transformer according to the magnetic bias degree of the predicted transformer temperature hysteresis influence interval. The invention achieves the purpose of reducing eddy current loss in the transformer.
Description
Technical Field
The invention relates to the technical field of data processing, in particular to a method for predicting DC magnetic bias transient eddy current loss of a transformer.
Background
The direct current flows into the transformer with unsaturated iron core to produce direct current magnetic bias effect by the superposition of direct current magnetic flux and no-load current, closed current line, i.e. eddy current effect, is formed in the conductor, the larger the magnetic flux of transient eddy current is along with the improvement of the capacity and voltage class of the transformer, the more the frame loss of structural members caused by magnetic bias is increased, the efficiency of the transformer is reduced, and the thermal performance of the transformer is deteriorated due to local overheating, so that the serious problems of aging of insulating materials, cracking and breakdown of transformer oil are finally caused. Therefore, in order to ensure the safe operation of the transformer and improve the operation reliability of the transformer, the operation power of the transformer needs to be reasonably controlled, and the eddy current loss is reduced.
The eddy current loss of the transformer is unavoidable, but the operating power can be reasonably selected through the temperature monitoring of the transformer, so that the purpose of reducing the eddy current loss is achieved; however, the existing physical calculation and temperature monitoring method can obtain simulation calculation of various transient processes, but the transient simulation calculation requires voltage constraint conditions, eddy current loss cannot be predicted, and local high temperature generated by the eddy current loss has hysteresis, so that when the temperature reaches a local high temperature threshold caused by the eddy current loss, the running power is readjusted, the temperature generated by the lost energy damages a transformer under the hysteresis condition, and the use efficiency of the transformer is reduced by setting a lower threshold.
Disclosure of Invention
The invention provides a method for predicting DC magnetic bias transient eddy current loss of a transformer, which aims to solve the existing problems.
The invention discloses a method for predicting DC magnetic bias transient eddy current loss of a transformer, which adopts the following technical scheme:
one embodiment of the invention provides a method for predicting DC magnetic bias transient eddy current loss of a transformer, which comprises the following steps:
collecting temperature data of all silicon steel sheets in the transformer at different moments and operating power of the transformer at different moments;
acquiring the moment when the power of the transformer changes according to the running power of the transformer at different moments; acquiring the overall temperature value of the transformer at each moment according to the temperature of all silicon steel sheets in the transformer at each moment, and drawing a change curve of the overall temperature of the transformer along with time according to the overall temperature of the transformer at each moment; acquiring a temperature hysteresis influence interval of the transformer through a change curve of the overall temperature of the transformer along with time and the moment when the power of the transformer changes;
acquiring the temperature difference coefficient of the transformer at all moments through the temperature data of the silicon steel sheet and the overall temperature of the transformer; acquiring power parameters of the transformer at the moment when the power changes through the operation power of the transformer; obtaining the magnetic bias degree of the transformer at all moments through the temperature difference coefficient of the transformer at all moments and the power parameter of the transformer at the moment when the power is changed;
obtaining the magnetic bias degree of a predicted transformer temperature hysteresis influence interval according to the magnetic bias degree of the transformer; and adjusting the operating power of the transformer according to the magnetic bias degree of the predicted transformer temperature hysteresis influence region.
Preferably, the moment when the power of the transformer changes includes the following specific steps:
and arranging the operation power of the transformers at different moments according to the time sequence to obtain an operation power sequence of the transformers at the time sequence, counting the time corresponding to the power with the later time sequence in the adjacent power with different magnitudes in the operation power sequence of the transformers, and recording the time as the time when the power of the transformers changes.
Preferably, the step of obtaining the overall temperature value of the transformer at each moment includes the following specific steps:
and taking the average value of the temperatures of all the silicon steel sheets in the transformer at each moment as the integral temperature value of the transformer at each moment.
Preferably, the drawing of the change curve of the overall temperature of the transformer with time includes the following specific steps:
and establishing a rectangular coordinate system by taking time as a horizontal axis and the overall temperature of the transformer as a vertical axis, filling the overall temperature of the transformer at each moment into the rectangular coordinate system to obtain a change curve of the overall temperature of the transformer along with time, and recording the change curve as an overall temperature value curve.
Preferably, the step of obtaining the temperature hysteresis influence region of the transformer includes the following specific steps:
according to the integral temperature value curve; acquiring the moment when the power of the transformer changes in the power data of the transformer, acquiring the slope of an integral temperature value curve of the moment when the power of the transformer changes, recording the slope change of the integral temperature value curve after the power of the transformer changes, and when the difference between the slope of the integral temperature value curve after the power of the transformer changes and the slope of the integral temperature value curve when the power of the transformer changes is smaller than a preset threshold value, recording the moment as a termination moment, and taking the time period between the moment when the power of the transformer changes and the termination moment as a temperature hysteresis influence interval under the moment when the power of the transformer changes;
and similarly, acquiring temperature hysteresis influence intervals of the transformers at all transformer power change moments, and taking the average value of the temperature hysteresis influence intervals of the transformers at all transformer power change moments as the temperature hysteresis influence interval of the transformers.
Preferably, the obtaining the temperature difference coefficient of the transformer at all times includes the following specific calculation formulas:
in the method, in the process of the invention,is->Temperature difference coefficient of transformer at moment +.>For the number of silicon steel sheets, < > and->Is the%>The silicon steel sheet is at the%>Temperature at moment->For transformers->The overall temperature at the moment, +.>Is at->The variance of the temperature of the silicon steel sheet at the moment,and->Respectively +.>The temperature of the silicon steel sheet with the highest temperature and the temperature of the silicon steel sheet with the lowest temperature at the moment.
Preferably, the step of obtaining the power parameter of the transformer at the moment when the power is changed includes the following specific steps:
and performing hyperbolic normalization according to the ratio of the difference between the power before the change of the transformer and the power after the change of the transformer and the rated power of the transformer, and adding 1 to the obtained hyperbolic normalized value to serve as the power parameter of the transformer at the moment when the power is changed.
Preferably, the method for obtaining the bias magnetic degree of the transformer at all times comprises the following specific steps:
calculating to obtain transformerA temperature difference coefficient of time, wherein->The moment can be any moment, obtain +.>The moment of the change of the power of the transformer immediately before the moment is marked +.>At time, calculate transformer at +.>Power parameters at time, finally the transformer is in +.>Power parameters at time and +.>The product of the temperature difference coefficients at the moment is taken as a transformer +.>Bias magnetic degree at time;
and similarly, obtaining the magnetic bias degree of the transformer at all times.
Preferably, the obtaining predicts the magnetic bias degree of the transformer temperature hysteresis influence region includes the following specific calculation formula:
in the middle ofTo predict the degree of bias in the temperature hysteresis influence region of the transformer,/->Is the temperature hysteresis influence zone of the transformer, +.>For the current moment +.>For the moment of change of the power of the transformer immediately preceding the current moment, < >>For transformers->Degree of bias at moment +_>For transformers->Degree of bias at time.
Preferably, the adjusting the operating power of the transformer according to the magnetic bias degree of the temperature hysteresis influence region of the predicted transformer comprises the following specific calculation formula:
and obtaining the standard magnetic bias degree of the transformers according to the standard power threshold value and the normal temperature value of each transformer, evaluating the magnetic bias degree of the predicted transformer temperature hysteresis influence interval by using the standard magnetic bias degree, and when the magnetic bias degree of the predicted transformer temperature hysteresis influence interval is larger than the standard magnetic bias degree, reducing power operation.
The technical scheme of the invention has the beneficial effects that: compared with the existing method for monitoring the eddy current loss generated by the magnetic bias effect of the transformer through a physical simulation calculation method, the method provided by the invention has the problem that the eddy current loss generated by the magnetic bias effect of the transformer cannot be predicted and controlled.
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In order to more clearly illustrate the embodiments of the invention or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, it being obvious that the drawings in the following description are only some embodiments of the invention, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
Fig. 1 is a flow chart of the steps of a method for predicting the transient eddy current loss of the direct current magnetic bias of the transformer.
Detailed Description
In order to further describe the technical means and effects adopted by the invention to achieve the preset aim, the following is a specific implementation, structure, characteristics and effects of a method for predicting dc bias transient eddy current loss of a transformer according to the invention, which are described in detail below with reference to the accompanying drawings and preferred embodiments. In the following description, different "one embodiment" or "another embodiment" means that the embodiments are not necessarily the same. Furthermore, the particular features, structures, or characteristics of one or more embodiments may be combined in any suitable manner.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.
The specific scheme of the method for predicting the DC bias transient eddy current loss of the transformer is specifically described below with reference to the accompanying drawings.
Referring to fig. 1, a flowchart of a method for predicting dc bias transient eddy current loss of a transformer according to one embodiment of the invention is shown, the method includes the following steps:
step S001: and collecting the temperature and the running power value of the silicon steel sheet of the transformer core.
It should be noted that, the iron core of the transformer is formed by stacking silicon steel sheets, in the process of inputting direct current into the transformer, a magnetic bias effect can be generated, eddy currents brought by magnetic bias generate eddy currents with different energy losses on different silicon steel sheets, the eddy currents enable the silicon steel sheets to generate local high temperature, the temperature change is predicted according to the temperature change of the silicon steel sheets along with the change of the running power, and the magnetic bias degree is obtained, so that the temperature and the running power of the silicon steel sheets need to be collected first.
Specifically, the first temperature sensor arranged on the silicon steel sheet is used for obtaining the first temperature sensor in the transformerThe silicon steel sheet is at the%>The temperature at the moment is marked as->The method comprises the steps of carrying out a first treatment on the surface of the The transformer is detected at +.>The power at the time is recorded asThe method comprises the steps of carrying out a first treatment on the surface of the The number of silicon steel sheets in the transformer is recorded as +.>。
Step S002: and acquiring a temperature hysteresis influence interval of the transformer according to the temperature change caused by the power of the transformer.
It should be noted that, the temperature of the transformer has a stage after the power is changed, when the transformer maintains the operation power, the temperature presents a stable value, when the power is changed, the temperature changes correspondingly, and after a period of time, the stable value is maintained; therefore, according to the temperature change trend and the power change, the temperature hysteresis influence interval of the transformer is obtained; the temperature hysteresis influence interval of the transformer is the time when the temperature of the transformer rises or falls from a stable value before the change to another stable value when the power is changed.
Specifically, firstly taking the average value of the temperatures of all silicon steel sheets at each moment as the integral temperature value of the transformer at each moment, and setting the transformer to be the firstThe overall temperature value at each instant is recorded as +.>Drawing a temperature change curve along with time through the integral temperature value of the transformer at each moment, and recording the temperature change curve as an integral temperature value curve; acquiring the moment when the power of the transformer changes in the acquired transformer power data, acquiring the slope of an integral temperature value curve at the moment when the power of the transformer changes, recording the slope change of the integral temperature value curve after the power of the transformer changes, and when the difference between the slope of the integral temperature value curve after the power of the transformer changes and the slope of the integral temperature value curve when the power of the transformer changes is smaller than a preset threshold value, indicating that the integral temperature of the transformer tends to be stable, wherein the time period between the moment when the power of the transformer changes and the moment when the integral temperature of the transformer tends to be stable is the moment when the power of the transformer changes>Is a temperature hysteresis influence zone of (2). The specific calculation formula is as follows:
in the middle ofTime for power change ∈>Temperature hysteresis influence interval of lower transformer, +.>Time for power change ∈>The overall temperature value of the down-converter, +.>For counting function +.>Is an exponential function based on natural constants, wherein +.>Is->Time temperature curve slope +.>Rear->Slope of time of day->For the a priori threshold value +.>To be described, the present embodiment is not particularly limited, < ->As the case may be.
When the power is changed, i.e. the temperature is changed from a steady state to a changed state, the slope is changed, the condition is not satisfiedHysteresis influence interval->The length is added with 1; when the temperature is restored from the varying state to the steady state, the +.>Obtain->The hysteresis of the moments affects the interval.
And similarly, acquiring temperature hysteresis influence intervals of the transformers at all transformer power change moments, and taking the average value of the temperature hysteresis influence intervals of the transformers at all transformer power change moments as the temperature hysteresis influence interval of the transformers.
So far, the temperature hysteresis influence interval of the transformer is obtained.
Step S003: and obtaining the magnetic bias degree of the transformer at all times according to the temperature difference of the silicon steel sheet in the transformer and the power of the transformer.
1. And obtaining the temperature difference coefficient of the transformer at all times.
It should be noted that, when the eddy current effect is small, the temperatures of the plurality of silicon steel sheets are approximately within a certain range, when the eddy current effect is obvious, the silicon steel sheets generate local high temperature, the local high temperature is transferred to the contacted silicon steel sheets along with the time change, that is, the diffusion exists in the area of the local high temperature in time sequence, so that the degree of magnetic bias of the eddy current effect under the power can be obtained through the temperature change trend of the silicon steel sheets, and the larger the degree is, the larger the power consumption loss is.
It should be further noted that, the dc bias of the transformer will generate an eddy current effect, and the greater the bias degree of the silicon steel sheet, the greater the degree of local high temperature, i.e. the higher the temperature difference compared with the normal temperature; and the temperature of the silicon steel sheet with the local high temperature is transferred to the adjacent silicon steel sheets along with the increase of the acquisition time, and the increase speed of the local high temperature area is faster, so that the magnetic bias degree is calculated by combining the temperature coefficient obtained by the temperature difference degree of the silicon steel sheet at the same time point with the change of the local high temperature area along with the change of time.
Specifically, according to the first of the transformersThe silicon steel sheet is at the%>Time temperature->Is in->The overall temperature value at the moment +.>Acquisition transformer in->The specific calculation formula of the temperature difference coefficient at the moment is as follows:
in the method, in the process of the invention,for transformers->Temperature difference coefficient at time, +.>For the number of silicon steel sheets, < > and->Is the%>The silicon steel sheet is at the%>Temperature at time, +.>For transformers->The overall temperature at the moment, +.>Is at->All silicon steel sheet temperature square under momentDifference (S)>And->Respectively +.>The temperature of the silicon steel sheet with the highest temperature and the temperature of the silicon steel sheet with the lowest temperature at the moment.
When the steady-state transformer temperature has eddy current effect, the local temperature is increased, so that the local area with higher temperature is smallerThe larger the temperature difference coefficient of the transformer is, but the whole temperature is +.>Gradually rise +.>The precision is reduced, and the highest temperature of the silicon steel sheet is +.>For the production of a vortex-generating sheet of silicon steel, the lowest temperature +.>As unaffected silicon steel sheet, the highest temperature and the lowest temperature are less varied, so +.>As a weight, the greater the diffusion degree is +.>The larger the value is, the weight of local high-temperature diffusion is taken as.
So far, the temperature difference coefficient of the transformer at all times is obtained.
2. And acquiring the power parameters of the transformer at the moment when the power changes.
The larger the temperature difference coefficient of the transformer, the higher the temperature of the local high temperature, that is, the stronger the eddy current loss. However, the overall temperature value is affected by power variation, and the transformer is more likely to generate eddy current effect due to damage of an insulating layer of an internal circuit and the like due to higher overall temperature when the transformer operates at high power, and the higher the overall temperature value is, the smaller the influence of the variation is, so that the weight of a specific power value is obtained according to the power value.
Specifically, hyperbolic normalization is performed according to the ratio of the difference between the power before the change of the transformer and the power after the change of the transformer to the rated power of the transformer, and 1 is added to the obtained hyperbolic normalized value to be used as the power parameter when the power of the transformer is changed. The specific calculation formula is as follows:
in the middle ofIn the order of->Power parameter at time and ∈>The moment is the moment when the power of the transformer changes; />For transformers->Power at time, and +.>The moment is the moment after the power of the transformer is changed;is->Power of the transformer at the moment of time, and +.>Time is the time before the power of the down-transformer is changed,/->For the rated power of the transformer, +.>。
Calculated byPower parameter at time ∈>The value range of (2) is +.>Power parameter->Indicating that the power is reduced, and +.>The smaller the decrease the greater; power parameter->Indicating an increase in power, and->The greater the rise the greater.
So far, the power parameters of the transformer at the moment when the power changes are obtained.
3. And obtaining the magnetic bias degree of the transformer at all times.
Specifically, the bias magnetic degree of the transformer at all moments is obtained according to the power parameter and the temperature difference coefficient of the transformer, specifically, the bias magnetic degree of the transformer is obtained through calculationA temperature difference coefficient of time, wherein->The moment can be any moment, obtain +.>The moment of the change of the power of the transformer immediately before the moment is marked +.>At time, calculate transformer at +.>Power parameters at time, finally the transformer is in +.>Power parameters at time and +.>The product of the temperature difference coefficients at the moment is taken as a transformer +.>The specific calculation formula of the bias magnetic degree at the moment is as follows:
in the method, in the process of the invention,for transformers->Bias magnetic degree at time; />In the order of->Power parameter at time, wherein +.>The moment is the transformer is->The moment when the power of the transformer changes before the moment; />For transformers->Temperature difference coefficient of time.
So far, the magnetic bias degree of the transformer at all times is obtained.
Step S004: and predicting the magnetic bias degree of the eddy current according to the magnetic bias degree combined with the current temperature and the power combined temperature hysteresis influence interval.
It should be noted that, because the operating power of the transformer in use is not uniformly distributed to the iron core silicon steel sheet, the silicon steel sheet generates eddy current effect, the local temperature of the silicon steel sheet is raised by dividing part of energy, the internal resistance is changed, so as to reduce the conversion efficiency of the transformer, the eddy current loss can be effectively avoided by selecting reasonable voltage and current through temperature monitoring, but the temperature has hysteresis in the transmission of the silicon steel sheet, and the silicon steel sheets are contacted with each other, so that the local high temperature of the magnetic bias eddy current is transmitted to the rest silicon steel sheets, the higher the local temperature is compared with the ambient temperature, the more serious the eddy current effect is indicated, therefore, the magnetic bias degree of the transformer at all times is obtained according to the power parameter of the transformer at all times and the temperature difference coefficient of the transformer at all times, and the eddy current loss is predicted.
Specifically, the product of the ratio of the time period between the current moment and the moment when the power of the transformer changes and the temperature hysteresis influence interval of the transformer is taken as the magnetic bias degree of the temperature hysteresis influence interval of the transformer by the difference between the magnetic bias degree of the transformer at the moment when the power of the transformer changes and the moment when the power of the transformer changes, and a specific calculation formula is as follows:
in the middle ofBias magnetic degree of temperature hysteresis influence zone of transformer, +.>Is the temperature hysteresis influence zone of the transformer, +.>For the current moment +.>For the moment of change of the power of the transformer immediately preceding the current moment, < >>For transformers->Degree of bias at moment +_>For transformers->Degree of bias at time.
So far, the magnetic bias degree of the temperature hysteresis influence section of the predicted transformer is obtained.
Step S005: and adjusting the operating power according to the eddy current resistance of the transformer and the magnetic bias degree.
It should be noted that, since the eddy current loss resistance of different transformer models is different and there is an error, the standard magnetic bias degree of the transformer is obtained according to the standard power threshold value, the temperature normal value, etc. of each transformerPredicting transformer temperature hysteresis using standard biasEvaluation of the degree of bias in the influence region, when predicting the degree of bias in the influence region of temperature hysteresis of the transformer +.>When the bias is too large, the power is required to be reduced. To achieve a reduction in eddy current losses in the transformer.
The foregoing description of the preferred embodiments of the invention is not intended to be limiting, but rather is intended to cover all modifications, equivalents, alternatives, and improvements that fall within the spirit and scope of the invention.
Claims (8)
1. The method for predicting the DC magnetic bias transient eddy current loss of the transformer is characterized by comprising the following steps of:
collecting temperature data of all silicon steel sheets in the transformer at different moments and operating power of the transformer at different moments;
acquiring the moment when the power of the transformer changes according to the running power of the transformer at different moments; acquiring the overall temperature value of the transformer at each moment according to the temperature of all silicon steel sheets in the transformer at each moment, and drawing a change curve of the overall temperature of the transformer along with time according to the overall temperature of the transformer at each moment; acquiring a temperature hysteresis influence interval of the transformer through a change curve of the overall temperature of the transformer along with time and the moment when the power of the transformer changes;
acquiring the temperature difference coefficient of the transformer at all moments through the temperature data of the silicon steel sheet and the overall temperature of the transformer; acquiring power parameters of the transformer at the moment when the power changes through the operation power of the transformer; obtaining the magnetic bias degree of the transformer at all moments through the temperature difference coefficient of the transformer at all moments and the power parameter of the transformer at the moment when the power is changed;
obtaining the magnetic bias degree of a predicted transformer temperature hysteresis influence interval according to the magnetic bias degree of the transformer; adjusting the operating power of the transformer according to the magnetic bias degree of the predicted transformer temperature hysteresis influence region;
the method for acquiring the temperature hysteresis influence interval of the transformer comprises the following specific steps:
according to the integral temperature value curve; acquiring the moment when the power of the transformer changes in the power data of the transformer, acquiring the slope of an integral temperature value curve of the moment when the power of the transformer changes, recording the slope change of the integral temperature value curve after the power of the transformer changes, and when the difference between the slope of the integral temperature value curve after the power of the transformer changes and the slope of the integral temperature value curve when the power of the transformer changes is smaller than a preset threshold value, recording the moment as a termination moment, and taking the time period between the moment when the power of the transformer changes and the termination moment as a temperature hysteresis influence interval under the moment when the power of the transformer changes;
the temperature hysteresis influence intervals of the transformers at the moment of power change of all the transformers are obtained in the same way, and the average value of the temperature hysteresis influence intervals of the transformers at the moment of power change of all the transformers is used as the temperature hysteresis influence interval of the transformers;
the specific calculation formula for acquiring the temperature difference coefficient of the transformer at all moments is as follows:
in the method, in the process of the invention,is->Temperature difference coefficient of transformer at moment +.>For the number of silicon steel sheets, < > and->Is the%>The silicon steel sheet is at the%>Temperature at moment->For transformers->The overall temperature at the moment, +.>Is at->Variance of the temperature of the silicon steel sheet at the moment +.>And->Respectively +.>The temperature of the silicon steel sheet with the highest temperature and the temperature of the silicon steel sheet with the lowest temperature at the moment.
2. The method for predicting the transient eddy current loss of the direct current magnetic bias of the transformer according to claim 1, wherein the moment when the power of the transformer changes comprises the following specific steps:
and arranging the operation power of the transformers at different moments according to the time sequence to obtain an operation power sequence of the transformers at the time sequence, counting the time corresponding to the power with the later time sequence in the adjacent power with different magnitudes in the operation power sequence of the transformers, and recording the time as the time when the power of the transformers changes.
3. The method for predicting the transient eddy current loss of the direct current magnetic bias of the transformer according to claim 1, wherein the step of obtaining the overall temperature value of the transformer at each moment comprises the following specific steps:
and taking the average value of the temperatures of all the silicon steel sheets in the transformer at each moment as the integral temperature value of the transformer at each moment.
4. The method for predicting the transient eddy current loss of the direct current magnetic bias of the transformer according to claim 1, wherein the drawing of the change curve of the overall temperature of the transformer with time comprises the following specific steps:
and establishing a rectangular coordinate system by taking time as a horizontal axis and the overall temperature of the transformer as a vertical axis, filling the overall temperature of the transformer at each moment into the rectangular coordinate system to obtain a change curve of the overall temperature of the transformer along with time, and recording the change curve as an overall temperature value curve.
5. The method for predicting the transient eddy current loss of the direct current magnetic bias of the transformer according to claim 1, wherein the step of obtaining the power parameter of the transformer at the moment when the power changes comprises the following specific steps:
and performing hyperbolic normalization according to the ratio of the difference between the power before the change of the transformer and the power after the change of the transformer and the rated power of the transformer, and adding 1 to the obtained hyperbolic normalized value to serve as the power parameter of the transformer at the moment when the power is changed.
6. The method for predicting the transient eddy current loss of the direct current magnetic bias of the transformer according to claim 1, wherein the method for obtaining the magnetic bias degree of the transformer at all times comprises the following specific steps:
calculating to obtain transformerA temperature difference coefficient of time, wherein->The moment can be any moment, obtain +.>The moment of the change of the power of the transformer immediately before the moment is marked +.>At time, calculate transformer at +.>Power parameters at time, finally the transformer is in +.>Power parameters at time and +.>The product of the temperature difference coefficients at the moment is taken as a transformer +.>Bias magnetic degree at time;
and similarly, obtaining the magnetic bias degree of the transformer at all times.
7. The method for predicting the transient eddy current loss of the direct current magnetic bias of the transformer according to claim 1, wherein the obtaining the magnetic bias degree of the predicted transformer temperature hysteresis influence interval comprises the following specific calculation formula:
in the middle ofTo predict the degree of bias in the temperature hysteresis influence region of the transformer,/->Is the temperature hysteresis influence zone of the transformer, +.>For the current moment +.>For the moment of change of the power of the transformer immediately preceding the current moment, < >>For transformers->Degree of bias at moment +_>For transformers->Degree of bias at time.
8. The method for predicting the transient eddy current loss of the direct current magnetic bias of the transformer according to claim 1, wherein the method for adjusting the operating power of the transformer according to the magnetic bias degree of the predicted transformer temperature hysteresis influence interval comprises the following specific calculation formula:
and obtaining the standard magnetic bias degree of the transformers according to the standard power threshold value and the normal temperature value of each transformer, evaluating the magnetic bias degree of the predicted transformer temperature hysteresis influence interval by using the standard magnetic bias degree, and when the magnetic bias degree of the predicted transformer temperature hysteresis influence interval is larger than the standard magnetic bias degree, reducing power operation.
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