CN117607640A - Alternating current arc modeling method considering multi-transient process and time-varying heavy arcing conditions - Google Patents
Alternating current arc modeling method considering multi-transient process and time-varying heavy arcing conditions Download PDFInfo
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Abstract
The invention discloses an alternating current arc modeling method considering multi-transient process and time-varying heavy arcing conditions, belonging to the field of modeling of electrical transient processes, comprising the following steps: constructing a first alternating current arc model according to the actual gap voltage and the arc channel dielectric breakdown threshold voltage, and judging the occurrence time of first gap breakdown; the circuit outside the breakdown gap is equivalent to impedance, the arc is equivalent to capacitance, and an equivalent circuit is constructed to solve LC oscillation components; constructing a traveling wave generating circuit according to distributed parameters of conductors at two ends of the breakdown gap to calculate traveling wave components; taking the sum of the LC oscillation component, the traveling wave component and the instantaneous impact component as a gap current of the breakdown gap to further calculate a predicted gap voltage; and constructing a second alternating current arc model according to whether the predicted gap voltage and the gap current meet the heavy breakdown condition or not, and determining whether heavy breakdown and heavy breakdown time occur or not. The reduction gap is broken down to produce various transient characteristics.
Description
Technical Field
The invention belongs to the field of modeling of electrical transient processes, and particularly relates to an alternating current arc modeling method considering multi-transient processes and time-varying heavy arcing conditions.
Background
The electric arc research has important significance for guaranteeing the stable operation of the power system, and the forming process of the electric arc plays a guiding role in parameter configuration of a plurality of arc extinction devices in the power grid. The dissipation rule of the electric arc is applied to the aspects of direct current transmission arc extinguishing devices, electric arc furnace metallurgy and the like. The signal characteristics of the electric arc are important to the connection state detection of the electrified train. It can be seen that research and modeling of arc characteristics has very wide practical value.
Unlike the single bleed charge process of a dc arc, the ac arc formation process is more complex. The existing arc model mainly comprises arc models of black boxes, such as models of Mayr, cassie and the like. The model is equivalent to an arc current and voltage waveform curve which changes along with arc current and voltage and time, and the arc current and voltage waveform curve can be reproduced through simulation under the configuration of proper parameters. The curve well restores various characteristics of the arc under the power frequency, such as overvoltage, zero-break phenomenon and the like during breakdown, and is widely applied to scenes with low requirements on high-frequency components of the arc.
However, the black box model largely ignores high frequency components caused by transient processes, resulting in lower prediction accuracy for subsequent arc re-ignition. In addition, the simplified scheme of time-varying conductance leads to the formation mechanism of an abnormal waveform curve being difficult to effectively embody, and is unfavorable for further electric arc characteristic research.
Disclosure of Invention
Aiming at the defects and improvement demands of the prior art, the invention provides an alternating current arc modeling method considering multi-transient process and time-varying heavy arcing conditions, which aims to restore various transient characteristics generated when a gap is broken down so as to improve the prediction precision of arc re-ignition.
To achieve the above object, according to one aspect of the present invention, there is provided an ac arc modeling method that accounts for a multi-transient process and a time-varying heavy arcing condition, comprising: constructing a first alternating current arc model according to the actual gap voltage and the arc channel dielectric breakdown threshold voltage, and judging the occurrence time of first gap breakdown; the circuit outside the breakdown gap is equivalent to impedance, the arc is equivalent to capacitance, so that an equivalent circuit is constructed, and LC oscillation components in the equivalent circuit are solved; constructing a traveling wave generating circuit according to distributed parameters of conductors at two ends of a breakdown gap, and calculating traveling wave components in the traveling wave generating circuit; calculating an instantaneous impact component according to the instantaneous voltage before the gap breakdown; taking the sum of the LC oscillation component, the traveling wave component and the instantaneous impact component as a gap current of a breakdown gap, and calculating the product of the gap current and an arc equivalent parameter to obtain a predicted gap voltage; and constructing a second alternating current arc model according to whether the predicted gap voltage and the gap current meet the heavy breakdown condition or not, and determining whether heavy breakdown and heavy breakdown time occur or not.
Still further, the first ac arc model is:
wherein,for the first gap breakdown judgment result, < >>A1 indicates breakdown, < >>A value of 0 indicates no breakdown;is->Actual gap voltage at time,/>，/>For the moment of occurrence of the first gap breakdown, +.>Striking the arc path mediumCrossing the threshold voltage.
Further, the LC oscillation component is:
；
；
wherein,for the LC oscillation component, < >>For the current moment +.>For the moment of occurrence of the first gap breakdown,for transient voltage before gap breakdown, +.>For transient current before gap breakdown, +.>、/>Equivalent resistance, equivalent inductance, respectively corresponding to the circuit outside the breakdown gap, < >>、/>Equivalent resistance and equivalent capacitance corresponding to the electric arc respectively, < ->Is an intermediate variable +.>Is a hyperbolic cosine function, ">As a hyperbolic sine function.
Furthermore, the construction of the traveling wave generating circuit according to the distributed parameters of the conductors at the two ends of the breakdown gap specifically comprises: and constructing a finite element circuit as the traveling wave generating circuit according to the distributed parameters of the conductors at the two ends of the breakdown gap and taking the length which does not generate traveling wave reflection as a distance.
Further, the calculating the traveling wave component in the traveling wave generating circuit specifically includes: distributed resistors at each microcell according to the finite element circuitInductance->Electric conduction->And capacitance to ground->Build->、/>Wherein ∈10 is equal to%>、/>Respectively->Time infinitesimal->A discrete current signal, a discrete voltage signal at the location; for micro-arc generation positionYuan->The following iterative updates are performed:
；
；
for infinitesimal units after arc occurrence positionThe following iterative updates are performed:
；
；
wherein,is a unit time infinitesimal->Is a unit length infinitesimal->、/>The equivalent resistance and the equivalent capacitance are respectively corresponding to the electric arc; according to the iterative updated ∈>Fitting to obtain continuous traveling wave components.
Still further, the second ac arc model is:
；
；
wherein,is->Time gap breakdown determination result, < >>，/>For the moment of occurrence of the first gap breakdown,is->Predicted gap voltage of time,/">Is->Time gap current,/">For gap voltage +.>Is (are) restoring curve>For the arc extinguishing condition->For a preset time interval, < >>、/>The first coefficient and the second coefficient are respectively used for controlling the heavy breakdown zero crossing condition.
Still further, the method further comprises the steps of,the method comprises the following steps:
wherein,、/>respectively obtaining a first time-varying coefficient and a second time-varying coefficient through experiments, and performing +.>、/>A first threshold value, a second threshold value, which are obtained through experiments, respectively,>for the moment of occurrence of the first gap breakdown, +.>、/>、/>The first time, the second time and the third time are obtained through experiments respectively.
According to another aspect of the present invention, there is provided a method of ac arc prediction accounting for multi-transient and time-varying heavy arcing conditions, comprising: the first alternating current arc model obtained by the method predicts the occurrence time of the first gap breakdown, and the second alternating current arc model obtained by the method determines whether the heavy breakdown and the heavy breakdown time occur.
According to another aspect of the present invention, there is provided an electronic apparatus including: a processor; a memory storing a computer executable program that, when executed by the processor, causes the processor to perform an ac arc modeling method that accounts for multi-transient and time-varying re-arcing conditions as described above, or to perform an ac arc prediction method that accounts for multi-transient and time-varying re-arcing conditions as described above.
According to another aspect of the present invention, there is provided a computer readable storage medium having stored thereon a computer program which when executed by a processor implements the ac arc modeling method as described above that accounts for multi-transient and time-varying re-arcing conditions, or implements the ac arc prediction method as described above that accounts for multi-transient and time-varying re-arcing conditions.
In general, through the above technical solutions conceived by the present invention, the following beneficial effects can be obtained:
(1) The alternating current arc modeling method is characterized in that from the point of signal generation, a high-frequency component is divided into an instantaneous impact component, an LC oscillation component and a traveling wave component, so that various transient characteristics generated when a gap is broken down are greatly reduced, and the prediction precision of arc reignition is improved; on the basis, the model considers the factor that the insulation recovery degree of gaps is different after multiple times of breakdown, sets a time-varying breakdown voltage threshold value, and further improves the prediction precision of arc reburning; simulation shows that the model can better restore transient pulse, LC vibration and various transient characteristics up to hundreds of kHz generated when a gap is broken down, and has high alternating current arc prediction precision;
(2) Firstly, constructing an instantaneous impact component according to the rule between arc channel voltage and current in the gap pre-breakdown process; then analyzing the equivalent impedance of an external circuit of the electric arc and the capacitive reactance of the electric arc, and combining the two parameters to construct an LC oscillating circuit so as to solve an LC oscillating component; considering that the original electrical structure between the electrodes is damaged due to the instant occurrence of the arc, further deducing a traveling wave component after establishing a traveling wave generating circuit by means of distributed parameters; finally, according to the characteristics of medium insulation recovery, a time-varying heavy arcing criterion is established, and the provided specific model has the advantages of high precision, small calculated amount and quick solving.
Drawings
FIG. 1 is a flow chart of an AC arc modeling method accounting for multi-transient and time-varying heavy arcing conditions provided by an embodiment of the present invention.
Fig. 2 is a schematic diagram of an experimental power grid topology structure according to an embodiment of the present invention.
Fig. 3 is an equivalent circuit for studying transient impact components provided by an embodiment of the present invention.
Fig. 4 is an equivalent circuit for researching LC oscillation according to an embodiment of the present invention.
Fig. 5 is a schematic diagram of LC transient charge-discharge simulation current according to an embodiment of the present invention.
Fig. 6 is a schematic diagram of a traveling wave generation circuit according to an embodiment of the present invention.
Fig. 7 shows a simulated traveling wave and a reconstructed traveling wave according to an embodiment of the present invention.
Fig. 8 is a simulation waveform obtained by the method according to the embodiment of the present invention.
Fig. 9 shows the actual measurement waveform of the experimental site recorder.
Detailed Description
The present invention will be described in further detail with reference to the drawings and examples, in order to make the objects, technical solutions and advantages of the present invention more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention. In addition, the technical features of the embodiments of the present invention described below may be combined with each other as long as they do not collide with each other.
In the present invention, the terms "first," "second," and the like in the description and in the drawings, if any, are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order.
FIG. 1 is a flow chart of an AC arc modeling method accounting for multi-transient and time-varying heavy arcing conditions provided by an embodiment of the present invention. Referring to fig. 1, in conjunction with fig. 2-9, a method for modeling an ac arc in the present embodiment and under multi-transient and time-varying heavy arcing conditions will be described in detail, and the method includes operations S1-S5.
And S1, constructing a first alternating current arc model according to the actual gap voltage and the arc channel dielectric breakdown threshold voltage, and judging the occurrence time of the first gap breakdown.
The physical factors of the actual breakdown gap are combined, the breakdown condition of the gap is designed, and the occurrence time of the first gap breakdown is judged based on the breakdown condition。
According to an embodiment of the invention, the first ac arc model is:
wherein,for the first gap breakdown judgment result, < >>A1 indicates breakdown, < >>A value of 0 indicates no breakdown;is->Actual gap voltage at time,/>，/>For the moment of occurrence of the first gap breakdown, +.>Is the arc channel dielectric breakdown threshold voltage. />In relation to the arc channel dielectric material.
And S2, the circuit outside the breakdown gap is equivalent to impedance, the arc is equivalent to capacitance, so as to construct an equivalent circuit, and LC oscillation components in the equivalent circuit are solved.
In this embodiment, the arc waveform is decomposed into three components, i.e., an instantaneous impact component, an LC oscillation component, and a high-frequency traveling wave component, from the formation mechanism of each component at the time of gap breakdown.
LC oscillation component is formed by arc channel capacitorAnd an external equivalent inductance->The oscillation is formed, and the operation S2 specifically includes the following sub-operations S21-S23.
In sub-operation S21, the breakdown gap external circuit is consolidated into, in accordance with the circuit impedance transformation theory, in combination with the breakdown gap external circuit centralization parameterIn the form of (a).
In sub-operation S22, the breakdown physical properties of the interstitial medium, or the statistical samples of the breakdown experiments thereof are investigated to equate the arc toIn the form of (a).
In sub-operation S23, the LC oscillation component is solved based on the equivalent parameters:
；
；
wherein,for LC oscillation component, +.>For the current moment +.>For the moment of occurrence of the first gap breakdown, +.>For transient voltage before gap breakdown, +.>For transient current before gap breakdown, +.>、/>Equivalent resistance, equivalent inductance, respectively corresponding to the circuit outside the breakdown gap, < >>、/>Equivalent resistance and equivalent capacitance corresponding to the electric arc respectively, < ->As an intermediate variable, the number of the variables,is a hyperbolic cosine function, ">As a hyperbolic sine function.
S3, constructing a traveling wave generating circuit according to distributed parameters of conductors at two ends of the breakdown gap, and calculating traveling wave components in the traveling wave generating circuit; the instantaneous impact component is calculated from the instantaneous voltage before the gap breakdown.
The traveling wave generating circuit is constructed according to the distributed parameters of the conductors at both ends of the breakdown gap, and specifically includes the following sub-operation S31.
In sub-operation S31, a finite element circuit is constructed as a traveling wave generating circuit according to the distributed parameters of the conductors at both ends of the breakdown gap to ensure that the length at which no traveling wave reflection occurs is a distance. Time keeping infinitesimalLength primordia->。
According to an embodiment of the present invention, a traveling wave component in a traveling wave generation circuit is calculated, specifically including the following sub-operation S32-S34.
In sub-operation S32, resistors distributed at each micro-element according to the finite element circuitInductance->Electric conduction->And capacitance to ground->Build->、/>Is the initial equation of (2):
；
；
wherein,、/>respectively->Time infinitesimal->Discrete current signals, discrete voltage signals at.
In sub-operation S33, for the infinitesimal at the arc occurrence positionThe following iterative updates are performed:
；
；
for infinitesimal units after arc occurrence positionThe following iterative updates are performed:
；
；
wherein,is a unit time infinitesimal->Is a unit length infinitesimal->、/>The equivalent resistance and the equivalent capacitance corresponding to the arc are respectively adopted.
In sub-operation S34, updated according to the iterationFitting to obtain continuous travelling wave components。
The instantaneous impact component is calculated from the instantaneous voltage before the gap breakdown, specifically including the following sub-operation S35.
In sub-operation S35, a transient impact component is obtained from quantitative physical analysis at a microscopic levelAlternatively, by +.>Sample from the instantaneous voltage before gap breakdown, statistics to get instantaneous impact component +.>。
And S4, taking the sum of the LC oscillation component, the traveling wave component and the instantaneous impact component as the gap current of the breakdown gap, and calculating the product of the gap current and the arc equivalent parameter to obtain the predicted gap voltage.
Gap current of breakdown gapPredicted gap voltage->The method comprises the following steps of:
；
；
and S5, constructing a second alternating current arc model according to whether the predicted gap voltage and the gap current meet the heavy breakdown condition or not, and determining whether heavy breakdown and heavy breakdown time occur or not.
According to an embodiment of the invention, the second alternating current arc model is constructed as follows:
；
；
wherein,is->Time gap breakdown determination result, < >>，/>For the moment of occurrence of the first gap breakdown,is->Predicted gap voltage of time,/">Is->Time gap current,/">For gap voltageOver time->Is (are) restoring curve>For the arc extinguishing condition->For a preset time interval, < >>、/>The first coefficient and the second coefficient are respectively used for controlling the heavy breakdown zero crossing condition;
the method comprises the following steps:
；
wherein,、/>respectively obtaining a first time-varying coefficient and a second time-varying coefficient through experiments, and performing +.>、/>A first threshold value, a second threshold value, which are obtained through experiments, respectively,>for the moment of occurrence of the first gap breakdown, +.>、/>、/>The first time, the second time and the third time are obtained through experiments respectively.
In this embodiment, the validity of the proposed method is verified by taking the parameters in the high-pressure experimental base in a certain area of China as an example. The topology of the experimental power grid is shown in fig. 2. The high-voltage alternating current power supply in the experimental field is as follows:
wherein,is the power frequency; />For the initial phase, simplify +.>；/>Is time.
In the high-voltage alternating current experimental field, the breakdown electrode has a rod-rod structure, and the medium of the breakdown gap is air. The first critical breakdown voltage of the air gap is therefore:
wherein,dielectric breakdown field strength for air; />Is the air gap spacing;
；
wherein,、/>、/>、/>、/>、/>、/>for the coefficients measured in the "double pulse" experiment for air +.>、/>、/>、/>、/>、、/>。
The first breakdown condition of the air gap is:
the resistance of the air gap before breakdown is extremely high, and the air gap is recorded. During pre-breakdown, the resistance value decays rapidly to a lower level:
wherein,the equivalent resistance before the air gap is broken down; />Is the equivalent resistance after stable arcing; />For the duration of the equivalent set value decay process, the duration is substantially uniform for the same type of air gap。
The experimental field shown in fig. 2 is abstracted into an equivalent circuit as shown in fig. 3. It should be noted that fig. 3 emphasizes the huge pulse caused by the power frequency voltage source in the breakdown process, and transient components are not counted. The current pulse component in the process can be deduced:
wherein,is an external equivalent impedance. Since the experimental environment is located in the high voltage station at a relatively close physical distance (less than 1 km) from the transformer, the impedance caused by the line, i.e. & lt & gt, can be ignored>. The equivalent value of the external impedance is then:
since the arc is generated by breakdown of the rod-rod structure, the structure is a typical capacitorThe medium is air. In the process of arc ignition, an LC charge-discharge structure is formed between the capacitor and the source end inductor, and LC oscillation occurs, so that high-frequency current is formed. The corresponding circuit is shown in fig. 4.
Equivalent impedance by external circuitIt can therefore be deduced that:
further, from the data collected during the arc burning process in the experiment, it is known that:
from knowledge of the series resonance, the resulting frequency of the current componentFor transient components independent of the power supply, +.>. First timeIn the charge and discharge process, transient current component +.>From the arc formation point to the source end, initial conditions can be cited:
；
；
will be of the above formula、/>、/>、/>、/>、/>Substituting the above formula to obtain LC charge/discharge current +.>As shown in fig. 5.
；
；
Measuring and calculating two polar plates at the arc breakdown position in advance, and respectively marking distributed parameters (resistance, inductance, conductance and susceptance) near the power grid side (hereafter referred to as side I) as：、/>、/>、/>。
Correspondingly, the ground side is denoted as the II side, and the distributed parameters are:、/>、/>、。
based on the parameters of both sides, a finite element long straight wire is constructed、/>I.e. a row wave generating circuit, as shown in fig. 6. The air gap is arranged between the two ends, and the equivalent is +.>And->Is a series of (a) and (b).
Setting an initial condition 1: before breakdown of the air gapTerminal voltage->Current->Has tended to steady state:
；
；
the initial condition 2 is as follows:terminal initial current->Voltage->All are zero:
；
；
wherein,is a time infinitesimal; />Is a spatial element index. Both are independent variables in the transmission line equation. Based on the initial conditions, the +.>Discrete travelling wave>. Windowing fast Fourier transform is carried out on the simulated travelling wave, and the offset is calculatedRemoving and restoring to attenuation sine form to obtain reconstructed traveling wave component +.>As shown in fig. 7.
The observation of the experimental waveform shows that: multiple re-breaks occur in the air gap after the first break down, which occurs when the LC oscillating current passes through zero at least the 2 nd time. At the moment, the arc of the arc path tends to be extinguished, and the voltage tends to be recovered. Bonding ofAfter the first breakdown of the air gap, the voltage required by the arc channel to be broken down again is far lower than that of the first breakdown until the LC oscillating current is flattened, the heavy breakdown does not occur any more, and the coefficient can be formulated based on experimental data:
；
；
；
by combining the above parameters, the LC oscillating current zero crossing is successively triggered to re-break down, so as to construct a time-varying arc current waveform, as shown in fig. 8. In contrast, the actual measurement waveforms collected in the above case are shown in fig. 9. Comparing fig. 8 and fig. 9, it can be known that the magnitude of the two is basically consistent with the trend of the waveform, and it is verified that the model constructed by the method can better restore multiple characteristics in the alternating current arc.
The embodiment of the invention also provides an alternating current arc prediction method considering the multi-transient process and the time-varying heavy arcing condition, which comprises the following steps: the first alternating current arc model obtained by the method predicts the occurrence time of the first gap breakdown, and the second alternating current arc model obtained by the method determines whether heavy breakdown and the moment of heavy breakdown occur.
The embodiment of the invention also provides electronic equipment, which comprises: a processor; and a memory storing a computer executable program that, when executed by the processor, causes the processor to perform the ac arc modeling method described above that accounts for the multi-transient and time-varying re-arcing conditions, or to perform the ac arc prediction method described above that accounts for the multi-transient and time-varying re-arcing conditions.
The embodiment of the invention also provides a computer readable storage medium, wherein a computer program is stored on the computer readable storage medium, and the program is executed by a processor to realize the alternating current arc modeling method for accounting for the multi-transient process and the time-varying heavy arcing condition or realize the alternating current arc prediction method for accounting for the multi-transient process and the time-varying heavy arcing condition.
It will be readily appreciated by those skilled in the art that the foregoing description is merely a preferred embodiment of the invention and is not intended to limit the invention, but any modifications, equivalents, improvements or alternatives falling within the spirit and principles of the invention are intended to be included within the scope of the invention.
Claims (10)
1. An ac arc modeling method that accounts for multiple transients and time varying heavy arcing conditions, comprising:
constructing a first alternating current arc model according to the actual gap voltage and the arc channel dielectric breakdown threshold voltage, and judging the occurrence time of first gap breakdown;
the circuit outside the breakdown gap is equivalent to impedance, the arc is equivalent to capacitance, so that an equivalent circuit is constructed, and LC oscillation components in the equivalent circuit are solved;
constructing a traveling wave generating circuit according to distributed parameters of conductors at two ends of a breakdown gap, and calculating traveling wave components in the traveling wave generating circuit; calculating an instantaneous impact component according to the instantaneous voltage before the gap breakdown;
taking the sum of the LC oscillation component, the traveling wave component and the instantaneous impact component as a gap current of a breakdown gap, and calculating the product of the gap current and an arc equivalent parameter to obtain a predicted gap voltage;
and constructing a second alternating current arc model according to whether the predicted gap voltage and the gap current meet the heavy breakdown condition or not, and determining whether heavy breakdown and heavy breakdown time occur or not.
2. The ac arc modeling method of claim 1, wherein the first ac arc model is:
；
wherein,for the first gap breakdown judgment result, < >>A1 indicates breakdown, < >>A value of 0 indicates no breakdown; />Is->Actual gap voltage at time,/>，/>For the moment of occurrence of the first gap breakdown, +.>And (5) the dielectric breakdown threshold voltage of the arc channel.
3. The ac arc modeling method of claim 1, wherein the LC oscillating component is:
；
；
wherein,for the LC oscillation component, < >>For the current moment +.>For the moment of occurrence of the first gap breakdown, +.>For transient voltage before gap breakdown, +.>For transient current before gap breakdown, +.>、/>Equivalent resistance, equivalent inductance, respectively corresponding to the circuit outside the breakdown gap, < >>、/>Equivalent resistance and equivalent capacitance corresponding to the electric arc respectively, < ->Is an intermediate variable +.>Is a hyperbolic cosine function, ">As a hyperbolic sine function.
4. The alternating current arc modeling method taking into account multi-transient and time-varying heavy arcing conditions of claim 1, wherein constructing the traveling wave generation circuit based on distributed parameters of conductors across the breakdown gap comprises:
and constructing a finite element circuit as the traveling wave generating circuit according to the distributed parameters of the conductors at the two ends of the breakdown gap and taking the length which does not generate traveling wave reflection as a distance.
5. The alternating current arc modeling method according to claim 4, wherein the calculating the traveling wave component in the traveling wave generating circuit comprises:
distributed resistors at each microcell according to the finite element circuitInductance->Electric conduction->And capacitance to ground->Establishing、/>Wherein ∈10 is equal to%>、/>Respectively->Time infinitesimal->A discrete current signal, a discrete voltage signal at the location;
for infinitesimal units at the position of arcThe following iterative updates are performed:
；
；
for infinitesimal units after arc occurrence positionThe following iterative updates are performed:
；
；
wherein,is a unit time infinitesimal->Is a unit length infinitesimal->、/>The equivalent resistance and the equivalent capacitance are respectively corresponding to the electric arc;
according to iteration after updatingFitting to obtain continuous traveling wave components.
6. The ac arc modeling method of any of claims 1-5, wherein the second ac arc model is:
；
；
wherein,is->Time gap breakdown determination result, < >>，/>For the moment of occurrence of the first gap breakdown, +.>Is->Predicted gap voltage of time,/">Is->Time gap current,/">For gap voltage +.>Is (are) restoring curve>For the arc extinguishing condition->For a preset time interval, < >>、/>The first coefficient and the second coefficient are respectively used for controlling the heavy breakdown zero crossing condition.
7. The alternating current arc modeling method taking into account multi-transient and time-varying heavy arcing conditions of claim 6,the method comprises the following steps:
；
wherein,、/>respectively obtaining a first time-varying coefficient and a second time-varying coefficient through experiments, and performing +.>、/>A first threshold value, a second threshold value, which are obtained through experiments, respectively,>for the moment of occurrence of the first gap breakdown, +.>、/>、/>The first time, the second time and the third time are obtained through experiments respectively.
8. An ac arc prediction method that accounts for multiple transients and time varying heavy arcing conditions, comprising: predicting the moment of occurrence of first gap breakdown by using the first alternating current arc model obtained by the method of any one of claims 1-7, and determining whether heavy breakdown and moment of heavy breakdown occur by using the second alternating current arc model obtained by the method of any one of claims 1-7.
9. An electronic device, comprising:
a processor;
a memory storing a computer executable program that, when executed by the processor, causes the processor to perform the ac arc modeling method of any one of claims 1-7 that accounts for multi-transient and time-varying re-arcing conditions, or to perform the ac arc prediction method of claim 8 that accounts for multi-transient and time-varying re-arcing conditions.
10. A computer-readable storage medium, on which a computer program is stored, characterized in that the program, when executed by a processor, implements the ac arc modeling method of any one of claims 1-7, which accounts for multi-transient and time-varying re-arcing conditions, or implements the ac arc prediction method of claim 8, which accounts for multi-transient and time-varying re-arcing conditions.
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