CN117574711B - Transformer substation 10kV outgoing line lightning-resistant level calculation method considering MOA configuration - Google Patents
Transformer substation 10kV outgoing line lightning-resistant level calculation method considering MOA configuration Download PDFInfo
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Abstract
The invention provides a calculation method of a 10kV outgoing line lightning-resistant level of a transformer substation taking MOA configuration into consideration, belongs to the technical field of line lightning-resistant level evaluation, and aims to provide a method for judging the lightning-resistant level of a distribution line by adopting lightning arrester energy so as to consider the influence of multiple lightning strokes on the lightning arrester in the distribution line; the method comprises the following steps: initializing to generate an overvoltage simulation model; the overvoltage simulation model responds to the currently input second lightning stroke parameter, the first lightning arrester parameter and the tower parameter, and outputs corresponding two-end voltage and instantaneous current when the lightning arrester with target property is subjected to multiple lightning strokes with different intensities; determining an absorbed energy based on the plurality of two-terminal voltages and the instantaneous current; determining a target absorbed energy from the plurality of absorbed energies based on the maximum through-flow energy; and determining multiple lightning strokes of the target intensity corresponding to the target absorption energy, and determining the first lightning stroke lightning current amplitude of the multiple lightning strokes of the target intensity as a lightning-resistant level threshold of the line.
Description
Technical Field
The invention relates to the technical field of line lightning-resistant level assessment, in particular to a method for calculating the 10kV outgoing line lightning-resistant level of a transformer substation in consideration of MOA configuration.
Background
Multiple lightning strokes are caused by continuous subsequent lightning strokes after the first lightning stroke, and when the zinc oxide arrester (MOA) does not discharge the energy absorbed by the first lightning stroke, new lightning impulse energy is rapidly accumulated, so that the probability of MOA damage is greatly increased.
However, in the research on the effect of multiple lightning strikes on lightning arresters, direct lightning strike is mainly used for power transmission lines. For distribution lines, the induction lightning is a main cause of tripping a line lightning stroke, and research on the overvoltage of the induction lightning during multiple lightning strokes is lacking at present. On the other hand, the distribution line has larger differences from the transmission line in terms of span, overvoltage form of lightning trip, trip mechanism and the like, and therefore, the MOA characteristics and the influence effect on the lightning resistance level of the line during multiple lightning strokes aiming at the characteristics of the distribution line are still lack to be studied.
Disclosure of Invention
In view of the above, the invention aims to provide a method for calculating the 10kV outgoing line lightning resistance level of a transformer substation in consideration of MOA configuration, and aims to solve the problem of the current lack of research on the effect of multiple lightning strokes OA of a distribution line on the lightning resistance level of the transformer substation.
The invention provides a method for calculating the 10kV outgoing line lightning resistance level of a transformer substation taking MOA configuration into consideration, which comprises the following steps:
Initializing to generate an overvoltage simulation model; the overvoltage simulation model comprises an induction Lei Moxing, a lightning arrester model and a pole tower model; the induction Lei Moxing is obtained based on the simulation of a first lightning strike parameter of multiple lightning strikes, and is used for obtaining induction lightning overvoltage, wherein the first lightning strike parameter comprises a plurality of first lightning strike lightning current amplitudes of the multiple lightning strikes, a target waveform and lightning strike frequency; the lightning arrester model is obtained based on simulation of first lightning arrester parameters, the first lightning arrester parameters comprise volt-ampere characteristics of the lightning arrester, and the lightning arrester model is used for simulating the properties of a real lightning arrester; the tower model is obtained based on tower parameter simulation, the tower parameters comprise line span, wire type and tower height, and the tower model is used for simulating the erection position and erection height of a real tower;
The overvoltage simulation model responds to the currently input second lightning stroke parameter, the first lightning arrester parameter and the tower parameter, and outputs corresponding two-end voltage and instantaneous current when the lightning arrester with target property is subjected to multiple lightning strokes with different intensities in a target installation mode; wherein, different lightning current amplitude values of the first lightning strike correspond to multiple lightning strikes with different intensities;
Determining the absorption energy corresponding to multiple lightning strokes of each intensity based on the voltages and the instantaneous currents at two ends corresponding to the multiple lightning strokes of the plurality of intensities;
determining a target absorbed energy from a plurality of the absorbed energies based on the maximum through-flow energy; the maximum through-flow energy is the square wave through-flow energy of the lightning arrester within a preset duration;
And determining multiple lightning strokes of the target intensity corresponding to the target absorption energy, and determining the first lightning stroke lightning current amplitude of the multiple lightning strokes of the target intensity as a lightning-resistant level threshold of 10kV outgoing lines of the transformer substation.
In a second aspect of the embodiment of the present invention, there is provided a transformer substation 10kV outgoing line lightning resistance level calculating apparatus considering MOA configuration, the apparatus comprising:
The initialization module is used for initializing and generating an overvoltage simulation model; the overvoltage simulation model comprises an induction Lei Moxing, a lightning arrester model and a pole tower model; the induction Lei Moxing is obtained based on the simulation of a first lightning strike parameter of multiple lightning strikes, and is used for obtaining induction lightning overvoltage, wherein the first lightning strike parameter comprises a plurality of first lightning strike lightning current amplitudes of the multiple lightning strikes, a target waveform and lightning strike frequency; the lightning arrester model is obtained based on simulation of first lightning arrester parameters, the first lightning arrester parameters comprise volt-ampere characteristics of the lightning arrester, and the lightning arrester model is used for simulating the properties of a real lightning arrester; the tower model is obtained based on tower parameter simulation, the tower parameters comprise line span, wire type and tower height, and the tower model is used for simulating the erection position and erection height of a real tower;
The output module is used for responding to the second lightning stroke parameter, the first lightning arrester parameter and the tower parameter which are input currently by the overvoltage simulation model, and outputting corresponding two-end voltage and instantaneous current when the lightning arrester with target property is subjected to multiple lightning strokes with different intensities in a target installation mode; wherein, different lightning current amplitude values of the first lightning strike correspond to multiple lightning strikes with different intensities;
the first determining module is used for determining the absorption energy corresponding to the multiple lightning strokes of each intensity based on the voltages and the instantaneous currents of the two ends corresponding to the multiple lightning strokes of the plurality of intensities;
The second determining module is used for determining target absorption energy from a plurality of absorption energy based on the maximum through-flow energy; the maximum through-flow energy is the square wave through-flow energy of the lightning arrester within a preset duration;
and the third determining module is used for determining multiple lightning strokes of the target intensity corresponding to the target absorption energy, and determining the first lightning stroke lightning current amplitude of the multiple lightning strokes of the target intensity as a lightning resistance level threshold value of the 10kV outgoing line of the transformer substation.
Compared with the prior art, the method for calculating the lightning resistance level of the 10kV outgoing line of the transformer substation taking MOA configuration into consideration has the following advantages:
according to the method, an overvoltage simulation model is built, multiple lightning stroke induction lightning actions are simulated through induction Lei Moxing in the overvoltage simulation model, the installation condition of a lightning arrester with a certain property in a real distribution line is simulated through a lightning arrester model and a pole tower model, the influence of the multiple lightning stroke induction lightning on the lightning arrester with a target property in a certain installation mode in the distribution line is obtained through simulation, then the lightning-proof level threshold of the distribution line is obtained according to the absorption energy of the lightning arrester with the target property and the maximum through-flow energy of the lightning arrester, and the angle of energy absorption of the lightning arrester from the line is provided; in addition, as the installation mode of the lightning arrester model with the target property in the line is adjustable, the energy absorption condition of the lightning arrester with the target property under different installation modes can be determined, and then the lightning-proof level threshold value of the lightning arrester with the target property when the lightning arrester with the target property receives multiple lightning strokes under different installation modes is determined; the energy absorption condition of the lightning arrester with the target property under multiple lightning strokes of a plurality of intensities is simulated in an overvoltage simulation model through the input second lightning stroke parameters, so that the influence of multiple lightning strokes of different intensities on the lightning arrester with the target property is clearly reflected.
Drawings
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention. In the drawings:
fig. 1 shows a step flowchart of a substation 10kV outgoing line lightning resistance level calculation method considering MOA configuration provided by an embodiment of the present invention;
FIG. 2 is a flow chart showing the steps of a method for determining the absorbed energy of a lightning arrester model in an embodiment of the invention;
FIG. 3 is a flow chart showing steps of a method for constructing an inductive lightning model in an embodiment of the invention;
FIG. 4 is a schematic diagram of the structure of an inductive lightning model in an embodiment of the invention;
FIG. 5 shows an induced lightning overvoltage waveform obtained by inputting a lightning current amplitude of 20kA and a lightning strike frequency of 1 into an induced lightning model, taking the lightning current amplitude and the lightning strike frequency as examples in the embodiment of the invention;
FIG. 6 illustrates a waveform schematic of multiple lightning strikes in an embodiment of the invention;
FIG. 7 is a schematic diagram showing a partial structure of an overvoltage simulation model in an embodiment of the present invention;
FIG. 8 shows an instantaneous current diagram of the arrester obtained by an overvoltage simulation model in a full line installation mode in an embodiment of the present invention;
Fig. 9 shows a voltage diagram of two ends of a lightning arrester obtained through an overvoltage simulation model in a full-line installation mode in an embodiment of the invention;
FIG. 10 is a schematic diagram of absorbed energy generated from instantaneous current and voltage across an embodiment of the present invention in a full line installation;
FIG. 11 shows an instantaneous current diagram of the lightning arrester obtained by an overvoltage simulation model when the grounding resistance is 30Ω in a fixed-point installation mode in the embodiment of the invention;
Fig. 12 shows a voltage diagram of two ends of a lightning arrester obtained by an overvoltage simulation model when the grounding resistance is 30Ω in a fixed-point installation mode in the embodiment of the invention;
Fig. 13 shows a schematic structural diagram of a substation 10kV outgoing line lightning resistance level calculating device considering MOA configuration according to an embodiment of the present invention.
Detailed Description
It should be noted that, without conflict, the embodiments of the present invention and features of the embodiments may be combined with each other.
The 10kV overhead line has large power supply area, complex network structure and fewer lightning protection measures, belongs to lightning protection weak links of an electric power system, and currently, a zinc oxide arrester (MOA) is installed to serve as the lightning protection measure of the 10kV overhead line, however, under multiple lightning strokes, the MOA is easy to cause the energy absorbed by the first lightning stroke which is not released yet, and the probability of MOA damage is increased due to the impact of new lightning energy.
However, the current research on the lightning resistance level of the 10kV overhead line is mostly judged by insulator flashover, and the method is mainly used for judging single lightning stroke, and the influence of the damage of the lightning arrester on the lightning resistance level of the line under multiple lightning strokes is ignored.
In view of the above, the invention provides a method for calculating the lightning-resistant level of a10 kV outgoing line of a transformer substation taking MOA configuration into consideration, which establishes induction Lei Moxing of multiple lightning strokes through simulation software, calculates the lightning-resistant level threshold according to the energy absorption condition of a lightning arrester of a10 kV overhead line under the action of the induction lightning of the multiple lightning strokes, considers the influence of the multiple lightning strokes on the lightning-resistant level of the lightning arrester, and further improves the operation reliability of a distribution line.
The method for calculating the 10kV outgoing line lightning resistance level of the transformer substation taking MOA configuration into consideration is described in detail below with reference to the accompanying drawings and with reference to the embodiments.
Referring to fig. 1, fig. 1 shows a step flowchart of a method for calculating a 10kV outgoing line lightning resistance level of a transformer substation taking MOA configuration into consideration, provided by an embodiment of the invention, as shown in fig. 1, where the method specifically includes:
Step S101, initializing and generating an overvoltage simulation model.
The overvoltage simulation model comprises an induction Lei Moxing, a lightning arrester model and a pole tower model; the induction Lei Moxing is obtained based on the simulation of a first lightning strike parameter of multiple lightning strikes, and is used for obtaining induction lightning overvoltage, wherein the first lightning strike parameter comprises a plurality of first lightning strike lightning current amplitudes of the multiple lightning strikes, a target waveform and lightning strike frequency; the lightning arrester model is obtained based on simulation of first lightning arrester parameters, the first lightning arrester parameters comprise volt-ampere characteristics of the lightning arrester, and the lightning arrester model is used for simulating the properties of a real lightning arrester; the tower model is obtained based on tower parameter simulation, the tower parameters comprise line span, wire types and tower height, and the tower model is used for simulating the erection position and the erection height of a real tower.
In the embodiment of the invention, an induction Lei Moxing, a lightning arrester model and a pole tower model are respectively generated, and then an overvoltage simulation model is obtained by combining the induction lightning arrester model, the lightning arrester model and the pole tower model. When the overvoltage simulation model simulates that the overvoltage of the multiple lightning stroke induction lightning acts on a certain lightning arrester in the distribution line, the transient current and the voltages at two ends generated by the lightning arrester are connected to the distribution line obtained by sequentially connecting a plurality of pole tower models when the simulation model is built, and the induction lightning model is connected with the lightning arrester model so as to simulate the condition that the overvoltage of the induction lightning stroke acts on the lightning arrester.
The induction lightning model is used for simulating induction lightning of multiple lightning strokes, the simulation result is induction lightning overvoltage, and the induction lightning overvoltage waveform and the overvoltage amplitude are obtained through the input lightning current amplitude of the first lightning stroke of the multiple lightning strokes; the lightning arrester model is used for simulating a specific type of lightning arrester, namely, the lightning arrester with target properties, wherein in the overvoltage simulation model, the volt-ampere characteristic of the lightning arrester is mainly related to determine the instantaneous current and the voltages at two ends of the lightning arrester under the corresponding induced lightning overvoltage, and then the lightning arrester model with the target volt-ampere characteristic is built in simulation software. The tower model is used for simulating the erection position and the erection height of a specific tower, and it can be understood that the simulation overvoltage model is a simulation of the condition when the line suffers multiple lightning strokes, and in order to enable the simulation result to be closer to the real result, parameters for constructing the tower model are the actual height of the tower, the actual erection distance between two adjacent towers and the like; the first arrester parameter is the volt-ampere characteristic parameter of the arrester of a specific model.
Since the overvoltage simulation model is composed of an induction Lei Moxing, a lightning arrester model and a pole tower model, the actual representation of the overvoltage simulation model is that the lightning arrester model with target properties in a line composed of a plurality of pole tower models generates instantaneous current and two-end voltage when the lightning arrester model is subjected to multiple lightning strokes with certain intensity.
In some embodiments, to make the simulation model more closely resemble the real line structure, properties of the real string of insulators are obtained through experimentation to obtain an insulator flashover model, which is also part of the overvoltage simulation model.
Step S102, the overvoltage simulation model responds to the second lightning stroke parameter, the first lightning arrester parameter and the tower parameter which are input currently, and outputs corresponding two-end voltage and instantaneous current when the lightning arrester with target property is subjected to multiple lightning strokes with different intensities in a target installation mode.
Wherein, different lightning current amplitude values of the first lightning stroke correspond to multiple lightning strokes with different intensities.
In the specific implementation, the instantaneous current and the voltage at two ends of the lightning arrester model with the target property are obtained by inputting the second lightning stroke parameter, the first lightning arrester parameter and the tower parameter of the overvoltage simulation model, wherein in order to obtain the lightning resistance level of the lightning arrester model with the target property, the tolerance condition of the lightning arrester model with the target property to multiple lightning strokes with different intensities is required to be determined, and in the simulation process, the first lightning stroke lightning current amplitude value in the input lightning stroke parameter is adjusted to simulate multiple lightning strokes with different intensities, so that the voltage at two ends and the instantaneous current of the lightning arrester model with the target property under the multiple lightning strokes with different intensities are obtained.
The second lightning strike parameter is used for defining multiple lightning strikes of one intensity, specifically comprises the first lightning strike lightning current amplitude value of the multiple lightning strikes, and inputs the first lightning strike lightning current amplitude value into the overvoltage simulation model to obtain multiple lightning strike induction lightning overvoltage under the intensity.
And the tower parameters are used for simulating the erection height of the tower and the distances among a plurality of towers in the real distribution line in the simulation process.
A first arrester parameter defining an arrester having a certain volt-ampere characteristic;
after the second lightning stroke parameter, the tower parameter and the first lightning arrester parameter are input, an overvoltage simulation model is operated to obtain the voltage and the instantaneous current at two ends of the lightning arrester with a certain volt-ampere characteristic under a certain strength of multiple lightning strokes; the instantaneous current of the lightning arrester represents the current generated by the lightning arrester under the condition of multiple lightning strokes, and the voltage at two ends represents the voltage at two ends of the lightning arrester after the instantaneous current is generated by the lightning arrester.
In some embodiments, the parameters of the lightning arresters may also be adjusted to determine the voltage and instantaneous current across the lightning arresters of different volt-ampere characteristics, and thus to select the type of lightning arrestor with the best lightning endurance level under multiple lightning strikes of the same intensity.
In some embodiments, the installation mode of the lightning arrester model on the circuit obtained by combining the plurality of tower models can be adjusted, so that the optimal installation mode of the lightning arrester is determined, and the lightning resistance level of the lightning arrester is highest in the optimal installation mode.
In the embodiment of the invention, in order to determine the lightning resistance level of the lightning arrester model with target properties, multiple lightning strokes with the same installation mode, the same lightning arrester model and different intensities are adopted for simulation, wherein, only the second lightning stroke parameter, namely the first lightning stroke lightning current amplitude value, is adjusted in the parameters of the overvoltage simulation model, and the simulation is carried out through a single variable, so that an accurate simulation result is obtained.
Step S103, based on the voltage and the instantaneous current at two ends corresponding to multiple lightning strokes of a plurality of intensities, the absorption energy corresponding to the multiple lightning strokes of each intensity is determined.
The distribution line allows single-phase earth faults, the line can trip only when two-phase or three-phase lightning overvoltage flashovers, if the lightning strike happens, the energy absorbed by the lightning arrester is lower than the maximum through-flow energy, the lightning arrester cannot be damaged, and the risk of inter-phase short circuit of the line cannot be caused; if the energy absorbed by the lightning arrester during lightning strike is higher than the maximum through-flow energy, the aging process of the lightning arrester can be accelerated, the damage probability of the lightning arrester is increased, and then interphase short circuit is caused. And after the lightning arrester is installed on the distribution line, the lightning resistance level of the line is defined as: when a lightning strike occurs, the energy absorbed by the lightning arrester does not exceed the maximum through-flow energy of the lightning arrester, and the lightning current amplitude value during interphase short-circuit does not occur in the line. Thus, the lightning-proof level of the line can be determined by judging whether the energy absorbed by the lightning arrester during a lightning strike exceeds the maximum through-flow energy.
Further, after acquiring the both-end voltage and the instantaneous current of the lightning arrester model having the target property, it is also necessary to determine the total absorbed energy of the lightning arrester model having the target property at the time of multiple lightning strokes. It will be appreciated that the main components of the arrester that absorb energy include: the lightning arrester is subjected to electric energy generated by multiple lightning strike induction lightning during multiple lightning strikes; when multiple lightning strokes are carried out, overvoltage is caused by the induction of the multiple lightning strokes, so that the valve plate of the lightning arrester is conducted to introduce the overvoltage to the ground, and at the moment, current flows through the valve plate of the lightning arrester to generate a part of electric energy; meanwhile, the lightning arrester is exposed in the environment, when multiple lightning strokes happen, the lightning arrester has the condition that electric energy is converted into heat energy, and part of the heat energy is dissipated in the environment, so that the total absorbed energy of the lightning arrester actually is the electric energy directly generated by the multiple lightning stroke induction lightning and the electric energy generated by the conduction of the valve plate of the lightning arrester, and meanwhile, the dissipated heat is subtracted.
In some embodiments, considering that the lightning arrester is a structure composed of a plurality of resistor pieces, wherein the resistor pieces are conductors, in multiple lightning, the resistor pieces can cause phenomena of large surface current density, small internal current density and serious surface heating due to skin effect, so that the lightning arrester is heated as a whole. Therefore, the absorption energy of the lightning arrester can be calculated from the heating condition of the lightning arrester, namely, the absorption energy of the lightning arrester is determined according to the energy generated by the whole heating of the lightning arrester, the electric energy generated by the conduction of the valve plate of the lightning arrester and the dissipated heat.
Step S104, determining target absorption energy from a plurality of absorption energies based on the maximum through-flow energy.
The maximum through-flow energy is the square wave through-flow energy of the lightning arrester within a preset duration; according to the related specifications of the alternating-current gapless metal oxide arrester, the 10kV line arrester should withstand 18 times of square wave current impact with the duration of 2ms without breakdown, flashover and damage, so that the maximum through-current energy of the arrester is defined as the square wave through-current energy within 2ms of the arrester in the embodiment of the invention. Further, after the absorption energy of the lightning arrester model having the target property corresponding to the multiple lightning strokes of different intensities is determined, the magnitudes of the plurality of absorption energies and the maximum through-flow energy are compared, and the absorption energy having the largest value is determined as the target absorption energy from among the absorption energies having the maximum through-flow energy or less.
In some embodiments, considering that one of the two ways of determining the absorbed energy is the absorbed energy determined from the macroscopic angle of the electrical energy received by the lightning arrester, and the other is the absorbed energy determined from the microscopic angle of the impact of the energy received by the lightning arrester on the resistor disc, the two ways of determining the absorbed energy are not conflicting, and when the two absorbed energies are both less than or equal to the maximum through-flow energy, it is determined that the lightning arrester is not damaged in this case.
Step S105, determining multiple lightning strokes of target intensity corresponding to the target absorbed energy, and determining the first lightning stroke lightning current amplitude of the multiple lightning strokes of the target intensity as a lightning-resistant level threshold of 10kV outgoing line of the transformer substation.
In the embodiment of the invention, the lightning-proof level of the circuit is defined as: when lightning stroke happens, the absorption energy of the lightning arrester is not just more than the maximum through-flow energy of the lightning arrester, and the lightning current amplitude value when interphase short circuit does not occur in the circuit, after the target absorption energy is determined, the first lightning current amplitude value corresponding to the absorption energy is used as the lightning resistance level threshold value of the circuit so as to evaluate the lightning resistance level of the circuit; the higher the lightning current amplitude of the first lightning stroke is, the stronger the lightning resistance level of the line is, so that the lightning resistance level of the line can be obtained under different installation modes of the lightning arrester, and the preferred installation mode of the lightning arrester is determined.
According to the substation 10kV outgoing line lightning resistance level calculation method considering MOA configuration, the induction Lei Moxing is built, and the lightning arrester model and the tower model are constructed so as to simulate the energy absorption condition of the lightning arrester under the condition of multiple lightning strike induction, and then the maximum induction lightning current amplitude of the energy tolerance of the lightning arrester is determined according to the energy absorption condition; therefore, the influence of multiple lightning strokes on the lightning arrester is considered when the lightning-resistant level of the line is evaluated, so that when the lightning arrester is installed on the distribution line, the accuracy of the lightning-resistant level evaluation is improved by adopting the model, and the operation reliability of the distribution line is further improved; in addition, in the simulation process, the lightning arrester model is directly connected with the tower model, and the connection mode of the lightning arrester and the plurality of tower models can be adjusted, so that different lightning-proof levels of the lightning arrester model can be obtained in various installation modes, and the basis is provided for researching the optimal mode of the lightning arrester model in a circuit more conveniently.
In some embodiments, the method for obtaining the absorbed energy may be lightning current energy of multiple lightning strokes received by the lightning arrester, or may be heat absorption of the lightning arrester after receiving multiple lightning strokes, or may be both obtained, and then, determining total absorbed energy according to energy generated when the valve plate of the lightning arrester is conducted and heat dissipation of the lightning arrester itself; at this time, referring to fig. 2, fig. 2 is a flowchart showing a step of a method for acquiring absorption energy under multiple lightning strikes with different intensities according to an embodiment of the present invention, and as shown in fig. 2, the method specifically includes:
s201, determining first absorption energy of the lightning arrester with target property under multiple lightning strokes of each intensity.
Wherein the first absorbed energy comprises energy of multiple lightning strokes received by the lightning arrester with the target property and/or heat absorption of the lightning arrester with the target property.
In the embodiment of the invention, when the first absorption energy represents multiple lightning strokes, the energy absorbed by the lightning arrester can be determined by the instantaneous current and the voltage at two ends generated by the energy absorbed by the lightning arrester, and also can be determined by the heat absorption capacity of the lightning arrester, namely the temperature rise condition of the resistor disc; the instantaneous current and the voltages at two ends generated when the lightning arrester absorbs energy are used for determining that the absorption energy of the lightning arrester is actually obtained from a macroscopic angle, the absorption energy of the lightning arrester is actually obtained from a microscopic angle, namely the heating condition of a resistor sheet in the lightning arrester, and the instantaneous current and the voltages at two ends are not in conflict, so that whether the absorption energy of the lightning arrester exceeds the maximum through-flow energy can be conveniently determined from two directions.
Wherein, in case the first absorbed energy is the energy of multiple lightning strokes received by the lightning arrester with the target property, the first absorbed energy is calculated by:
first, determining a lightning strike duration of each lightning strike in multiple lightning strikes of each intensity;
secondly, determining the energy absorbed by the lightning arrester with target properties at each lightning strike in multiple lightning strikes based on the lightning strike duration, the instantaneous current and the terminal voltage;
And finally, determining the sum of the energy absorbed by the lightning arresters with target properties corresponding to each lightning strike in multiple lightning strikes as the first absorbed energy.
In the embodiment of the invention, multiple lightning strokes are multiple lightning stroke processes, wherein the current-like amplitude of each lightning stroke is different, and the instantaneous current and the voltage at two ends correspondingly generated by the lightning arrester are different, so that the lightning stroke duration of each lightning stroke needs to be determined firstly when the first absorbed energy of the lightning arrester is calculated, the energy absorbed by the lightning arrester under each lightning stroke is obtained, and the total energy absorbed by the lightning arrester under multiple lightning strokes is obtained.
Taking multiple lightning strike frequency as 2 times as an example, determining the duration of each lightning strike, wherein the duration of the first lightning strike is 0-t 1, the duration of the second lightning strike is t 1-t2, and if the duration of the first lightning strike is 0-0.1s, and the duration of the second lightning strike is 0.1-0.25 s, the energy absorbed by the lightning arrester of the first lightning strike is calculated by the following formula (1):
Wherein W 1 represents the energy absorbed by the lightning arrester of the first lightning stroke; p (t) represents the instantaneous power of the arrester; u (t) is the voltage at two ends of the lightning arrester, and i (t) is the instantaneous current of the lightning arrester.
The energy absorbed by the lightning arrester of the second lightning stroke is calculated by the following formula (2):
Wherein W 2 represents the energy absorbed by the lightning arrester of the first lightning stroke; p (t) represents the instantaneous power of the arrester; u (t) is the voltage at two ends of the lightning arrester, and i (t) is the instantaneous current of the lightning arrester.
Wherein, in the case that the first absorption energy is the heat absorption amount of the lightning arrester having the target property, the first absorption energy is calculated by:
first, a radial flow depth of a surface current under multiple lightning strokes of each intensity is determined for each resistive sheet in the lightning arrester having a target property based on the second lightning arrester parameter and the current frequency of the instantaneous current.
And secondly, establishing a heat dissipation model of the lightning arrester with the target property, and determining the heat absorption temperature of each resistor disc according to a finite element calculation method.
Finally, the first absorbed energy is determined based on the radial flow depth, the second arrester parameter, and the endothermic temperature.
In the embodiment of the invention, the second lightning arrester parameters further comprise magnetic permeability and electric conductivity of the lightning arrester model, wherein the magnetic permeability and the electric conductivity are used for obtaining alternating current radial depth under the skin effect of the lightning arrester resistor disc. The skin effect refers to the phenomenon that when alternating current or alternating electromagnetic field exists in a conductor, current inside the conductor is unevenly distributed, and current is concentrated on the surface of the conductor. The resistor disc of the lightning arrester is influenced by the skin effect, and the higher the current frequency is, the more serious the resistor disc heats, the radial flow depth of current in the resistor disc can be determined according to the influence of the skin effect, and then the heat absorption capacity of the resistor disc is obtained.
Specifically, the radial flow depth of the current under the skin effect is determined by the following formula (3):
wherein r is skin depth (mm), ω is angular frequency (rad/S), μ is magnetic permeability (H/m), and γ is electrical conductivity (S/m); where angular frequency ω=2pi f, f is the current frequency.
After determining the radial flow depth of the current of the resistor disc, in the multi-physical-field simulation software COMSOL, based on the second arrester parameter, establishing a heat dissipation model of the arrester, and adopting an electric-thermal-fluid coupling finite element calculation method to grid-divide a calculation area of the arrester so as to construct a coefficient matrix of each grid, and further performing time scale dispersion to obtain the heat absorption temperature delta T of each resistor disc, wherein the heat absorption quantity delta Q 1 of the arrester can be calculated by the following formula (4):
Wherein Δq 1 is the heat dissipation capacity of the arrester, and c MOR is the specific heat capacity of the resistor disc; m i is the mass of the i-th resistor; n is the number of the resistor blocks; deltat i is the heat dissipation temperature of the ith resistor disc, and r is the skin depth.
S202, acquiring the power frequency freewheel time of the lightning arrester with the target property under multiple lightning strokes of each intensity.
And S203, determining the second absorbed energy of the lightning arrester with the target property based on the power frequency freewheel time, the two-end voltage and the instantaneous current.
In the embodiment of the invention, after the line is struck by lightning, if the voltage of the lightning is large enough, the valve plate of the lightning arrester is conducted, and at the moment, power frequency current flows. When the 10KV neutral point ungrounded system is in single-phase grounding short circuit, fault phase current is rapidly increased, and as the duration of multiple lightning strokes is longer than that of single lightning strokes, power frequency energy absorbed before the power frequency current of the lightning arrester is cut off must be considered, and the power frequency energy is second absorbed energy.
The power frequency follow current time represents the duration of the generated power frequency current when the valve plate of the lightning arrester with the target property is conducted. The power frequency freewheel time can be determined by determining the generation time of the power frequency current and the end time of the power frequency current, or detecting the conduction condition of the valve plate of the arrester, starting timing when the valve plate of the arrester is conducted until the valve plate of the arrester is closed, and obtaining the power frequency freewheel time.
Specifically, the power frequency freewheel time, the instantaneous current and the instantaneous voltage of the lightning arrester are input into the electromagnetic transient analysis software ATP-EMTP, and the second absorption energy is calculated by adopting the following formula (5):
Wherein W 3 is the second absorbed energy, t 3 is the power frequency freewheel time, u (t) is the voltage at two ends of the lightning arrester, and i (t) is the instantaneous current of the lightning arrester.
S204, acquiring the heat dissipation capacity of the lightning arrester with the target property based on the second lightning arrester parameter of the lightning arrester with the target property.
Wherein the second arrester parameters include the number of resistive sheets in the arrester having the target property, the specific heat capacity, and the mass of each of the resistive sheets.
In the embodiment of the invention, as the lightning arrester is exposed to the environment, when the resistor sheet heats, part of heat is dissipated to the environment, and the heat dissipating capacity of the lightning arrester is required to be obtained, so that the part of energy is subtracted from the absorbed energy of the lightning arrester, and the energy actually absorbed by the lightning arrester is determined.
The method for acquiring the heat dissipation capacity of the lightning arrester specifically comprises the following steps of:
Firstly, determining the heat dissipation temperature of each resistance sheet in the lightning arrester model with target properties by adopting an electric-thermal-fluid coupling finite element calculation method;
then, based on the second arrester parameter and the heat dissipation temperature, a heat dissipation capacity of the arrester having the target property is determined.
In the specific implementation, in the multi-physical-field simulation software COMSOL, a heat dissipation model of the lightning arrester is built based on the second lightning arrester parameters, and a calculation area of the lightning arrester is subjected to grid division by adopting an electric-thermal-fluid coupling finite element calculation method, so that a coefficient matrix of each grid is constructed, and further, a time scale dispersion is carried out to obtain the heat dissipation temperature delta T of each resistor sheet, and the energy delta Q dissipated during heat dissipation of the lightning arrester can be obtained through calculation according to the following formula (6):
Wherein DeltaQ is the heat dissipation capacity of the lightning arrester, and c MOR is the specific heat capacity of the resistor disc; m i is the mass of the i-th resistor; n is the number of the resistor blocks; Δt i is the heat dissipation temperature of the i-th resistor.
And S205, determining the sum of the first absorption energy and the second absorption energy as lightning current energy.
And S206, determining the difference value between the lightning current energy and the heat dissipation capacity as the absorption energy.
In the embodiment of the invention, after the first absorption energy and the second absorption energy are obtained, the absorption energy of the lightning arrester with target property under multiple lightning strokes is shown after the first absorption energy and the second absorption energy, namely the lightning current energy, the value is not the energy of the lightning stroke of the lightning arrester under multiple lightning strokes, and the heat dissipation capacity of the lightning arrester needs to be subtracted, so that the absorption energy W MOA can be shown as W MOA＝W1+W2+W3 -delta Q for two types of first absorption energy obtaining modes, and the absorption energy W MOA represents the absorption energy of the lightning arrester obtained under the condition that the first absorption energy is calculated by adopting the lightning current energy; or may be represented as W MOA＝ΔQ1+W3 - Δq, which characterizes the absorbed energy of the arrester obtained in the case where the first absorbed energy is calculated using the amount of absorption of the arrester itself.
In particular, in the case of determining the first absorbed energy from the lightning current energy at a macroscopic angle, the step of obtaining the absorbed energy of the lightning arrester having the target property is: firstly, determining first absorption energy, namely W 1+W2, according to instantaneous current and two-end voltage generated by a lightning arrester with target property in the duration of each lightning stroke in multiple lightning strokes; then, according to the current generated when the lightning arrester valve plate is conducted, determining second absorption energy, namely W3; then, the heat dissipation amount Δq of the arrester is determined again, and the absorption energy of the arrester having the target property at this time is W 1+W2+W3 - Δq.
In the case where the first absorbed energy is determined from the amount of absorbed heat of the lightning arrester at a microscopic angle, the step of obtaining the absorbed energy of the lightning arrester having the target property is: firstly, determining the heat absorption quantity of the lightning arrester with the target property, namely delta Q 1, according to the current frequency of the lightning arrester with the target property and the second lightning arrester parameters including the electric conductivity and the magnetic permeability of the lightning arrester with the target property; then, according to the current generated when the lightning arrester valve plate is conducted, determining second absorption energy, namely W3; then, the heat dissipation amount Δq of the arrester is determined again, and the absorption energy of the arrester having the target property at this time is Δq 1+W3 to Δq.
The absorption energy of the lightning arrester with target properties is determined from a macroscopic angle and a microscopic angle respectively through two different modes, and then the two absorption energies are compared with the maximum through-flow energy of the lightning arrester, so that whether the lightning arrester can bear the absorption energy is judged, therefore, the two absorption energies are taken as criteria, the lightning arrester is determined to not absorb excessive energy as a whole, the lightning-proof level of the circuit is improved under the condition that the resistor sheet of the lightning arrester is not damaged, the evaluation accuracy of the lightning-proof level is improved, and the operation reliability of the distribution circuit is further improved.
In some embodiments, the method for determining the target absorbed energy specifically includes the steps of:
firstly, determining at least one candidate absorption energy which is smaller than or equal to the maximum through-flow energy from a plurality of absorption energies;
second, comparing the magnitude of the value of the at least one candidate absorbed energy;
and finally, determining the candidate absorption energy with the maximum value as the target absorption energy.
In the embodiment of the invention, if a plurality of candidate absorption energies are less than or equal to the maximum through-flow energy in the plurality of absorption energies obtained through judgment, after the candidate absorption energies are determined, the plurality of candidate absorption energies are compared to determine the candidate absorption energy with the largest value, and the candidate absorption energy is taken as the target absorption energy. The method is characterized in that the evaluation of the lightning resistance level of the line is to determine how many multiple lightning strokes of the lightning current amplitude can be borne by the line at maximum, the target absorption energy actually represents the maximum limit of the energy absorbed by the lightning arrester, and the corresponding first lightning current amplitude is the maximum intensity of the multiple lightning strokes which can be borne by the line.
Next, the induction Lei Moxing, the arrester model, and the tower model are set up as follows:
firstly, referring to fig. 3 in particular, fig. 3 shows a flowchart of steps of a method for constructing a surface of an inductive lightning model according to an embodiment of the present invention, and as shown in fig. 3, the method for constructing an inductive lightning model specifically includes:
Step S301, determining the lightning strike time interval based on the counted historical time interval of multiple lightning strikes.
Specifically, whether a group of continuous lightning strikes is multiple lightning strikes is determined according to the time intervals of the lightning strikes, and when the time intervals of the lightning strikes are small enough, the multiple lightning strikes discharge along the same discharge channel, and MOA energy accumulation is easy to cause. According to GB/T21714.1-2015, the time interval range of multiple negative polarity lightning strokes is 10ms-250ms, so that a plurality of historical multiple lightning strokes are obtained, the lightning striking time interval of each historical multiple lightning stroke is determined, and the lightning striking time interval with the largest occupation ratio is counted to be used as the lightning striking time interval of the simulated multiple lightning strokes.
Step S302, determining the lightning strike frequency based on the counted historical lightning strike frequency of multiple lightning strikes.
And step S303, determining the waveform of the first lightning stroke of the multiple lightning strokes specified by the lightning protection standard as the target waveform.
Specifically, the lightning strike frequency of a plurality of historical multiple lightning strikes is obtained, the lightning strike frequency with the largest proportion among the lightning strike frequencies is taken as the lightning strike frequency of the simulated multiple lightning strikes, and a waveform specified by a standard document IEC61312-1 of lightning protection standards is taken as a target waveform, wherein the waveform of the first lightning strike is 10/350 mu s, and the waveform of the subsequent lightning strike is 0.25/100 mu s.
Step S304, obtaining the first lightning current amplitude of multiple lightning strokes with different intensities.
In the embodiment of the invention, the first lightning current amplitudes of multiple lightning strokes with different intensities are obtained, namely a plurality of different first lightning current amplitudes are obtained, and the specific obtaining method comprises the following steps:
firstly, acquiring the probability of the lightning current amplitude of the historical first lightning stroke of multiple lightning strokes;
then, determining at least one target first lightning current amplitude value with the probability larger than or equal to a preset probability from a plurality of historical first lightning current amplitude values;
and finally, determining at least one target first lightning current amplitude as the first lightning current amplitude.
Specifically, the probability of lightning current amplitude of a plurality of multiple lightning strokes can be counted, wherein the probability is characterized by the probability that the lightning current amplitude of the first lightning stroke of the multiple lightning strokes exceeds a specific lightning current value, and the probability is obtained through the following formula (7):
wherein P is the probability of the lightning current amplitude, and I is the lightning current amplitude.
Therefore, the probability P of each lightning current amplitude value is obtained, at least one lightning current amplitude value with the probability exceeding 50% of the lightning current amplitude values in the plurality of lightning current amplitude values is determined and used as the first lightning current amplitude value of multiple lightning strokes, and then the lightning current amplitude values of multiple lightning strokes with different intensities are obtained.
And step S305, constructing a lightning current Heidler model based on the lightning strike time interval, the lightning strike frequency, the target waveform and the first lightning strike lightning current amplitude.
Step S306, constructing the induction Lei Moxing in the simulation software according to the lightning channel wave impedance, the circuit element and the lightning current Heidler model.
Specifically, a lightning strike time interval, a lightning strike frequency, a target waveform and a first lightning strike lightning current amplitude are input into simulation software to generate a lightning current Heidler model, and then induction Lei Moxing of multiple lightning strikes shown in fig. 4 is obtained through simulation according to lightning channel wave impedance, a circuit element and the lightning current Heidler model, wherein R represents resistance, L represents capacitance, C represents inductance, I represents induced lightning current generated when multiple lightning strikes are caused by a circuit, V represents overvoltage generated by the induced lightning current, multiple lightning strike points are lightning strike positions of multiple lightning strikes, and multiple lightning strike induction points are positions for generating induced lightning overvoltage; the induction lightning model is used for obtaining induction lightning overvoltage of multiple lightning strokes, and the induction lightning overvoltage is obtained through the following formula (8):
Wherein I is the lightning current amplitude, in kA; h is the average height of the wire, and 15m is taken; s is the length of the wire where any point of the wire is horizontally closest to the lightning strike point (S >65 m), and Ug represents the induced voltage amplitude (kV). Thus, the induced lightning model according to the embodiment of the invention can obtain induced lightning overvoltage according to the input multiple lightning strike parameters, and by taking a lightning strike with a lightning current amplitude of 20kA and a lightning strike frequency of 1 as an example, the lightning current amplitude and the lightning strike frequency are input into the induced lightning model to obtain an induced lightning overvoltage waveform as shown in fig. 5.
Secondly, the tower model can be built based on the erection parameters of the tower and the line span parameters by adopting related technologies.
Then, the lightning arrester model is established in the following way:
The simulation is carried out by adopting an MOV Type92 lightning arrester module in ATP-EMTP, and the rated voltage is 17kV by taking a (YH) HY5WS-17/50 lightning arrester as an example, and the voltage-current characteristics of the lightning arrester are set according to the Type.
And finally, connecting the induction Lei Moxing, the lightning arrester model and the pole tower model in ATP-EMTP simulation software to obtain an overvoltage simulation model.
In some embodiments, the target mounting means includes full line mounting, tower spacer mounting, and fixed point mounting; the overvoltage simulation model is obtained by connecting the induction lightning model, the lightning arrester model and a plurality of pole tower models, and the lightning arrester model is installed in a line obtained by sequentially connecting the plurality of pole tower models in the target installation mode;
wherein, under the condition that the target installation mode is the full line installation, each group of lightning arrester models is connected at a position corresponding to each tower model;
In the case that the target installation mode is that the tower isolating models are installed, a group of lightning arrester models are installed at intervals, and each group of lightning arrester models is opposite to the position of the tower model;
And under the condition that the target installation mode is the fixed-point installation, installing the lightning arrester model at a position corresponding to one tower model, wherein the circuit is provided with a grounding resistor.
Wherein, the whole line is installed as a lightning arrester on each tower of the easy-to-strike section of the line; the isolating tower is installed as a group of lightning arresters installed on a base tower, the fixed-point installation is that only a group of lightning arresters are installed on a base tower in a line, and the grounding resistor is correspondingly arranged.
In the embodiment of the present invention, the three installation modes are specifically described by taking fig. 7 as an example:
In the full line installation mode, in the overvoltage simulation model shown in fig. 7, in addition to installing the lightning arrester at the corresponding position of the #1 tower, the lightning arrester model is installed correspondingly from the subsequent #2 tower to the #3 tower to the #6 tower; in the tower isolation installation mode, the lightning arrester is installed at the corresponding position of the #1 tower, and further in the subsequent #3 tower and #5 tower; in the fixed-point installation mode, the lightning arrester is installed at the position corresponding to the #1 tower, and the grounding resistor is also arranged on the #1 tower.
Under three lightning arrester installation modes, the current of the lightning arrester corresponding to the lightning overvoltage access pole tower is the largest, and then when the line is Lei Shui times durable according to the maximum through-flow energy of the lightning arrester, only whether the absorbed energy of the lightning arrester corresponding to the lightning overvoltage access pole tower exceeds the maximum through-flow energy of the lightning arrester is analyzed, namely, in the specific simulation process, under the condition that a plurality of groups of lightning arrester models are installed, only the absorbed energy of the lightning arrester model connected with the induction lightning model is determined.
In a specific simulation process, a plurality of tower models are connected to obtain a line, an installation mode is adopted on the line to install a lightning arrester model, wherein when the lightning-proof level of the line under different lightning arrester installation modes is analyzed, the lightning arrester models connected with the induction lightning arrester models can be arranged at the same position of the line, and different installation modes are formed by controlling the installation positions of other lightning arrester models so as to control variables, so that the lightning-proof level evaluation accuracy of the line with different installation modes is higher.
According to the substation 10kV outgoing line lightning-resistant level calculation method considering MOA configuration, disclosed by the embodiment of the invention, the induction lightning overvoltage of multiple lightning strokes is simulated by building the induction lightning model, the lightning arrester with target properties is simulated by building the lightning arrester model, the actual tower of the tower model is built, and the induction lightning voltage model, the lightning arrester model and the tower model are combined to obtain an overvoltage simulation model, so that the overvoltage simulation model can determine the instantaneous current and the voltages at two ends of the lightning arrester with target properties according to the lightning stroke parameters of the multiple lightning strokes; then, according to the instantaneous current, the voltages at two ends and the heat absorption condition of the lightning arrester with target property, respectively obtaining the absorption energy of two angles, respectively comparing the two absorption energies with the maximum through-flow energy to accurately determine whether the lightning arrester model with target property is damaged under multiple lightning strokes with corresponding strength, further determine the lightning-resistant level of the line, and improve the accuracy of the lightning-resistant level evaluation of the line; in addition, according to the different installation modes of the embodiment of the invention, the setting positions of other lightning arrester models which do not receive the multiple lightning stroke induction lightning are adjusted, so that the lightning resistance level of the line under different installation modes can be conveniently and quickly determined.
The above process is described below in connection with a specific example:
Firstly, determining first lightning strike parameters of multiple lightning strikes, wherein the first lightning strike parameters comprise lightning strike time intervals, lightning strike frequency, waveform and first lightning strike lightning current assignment of the multiple lightning strikes; the specific acquisition mode of the first lightning stroke parameter is as follows: according to GB/T21714.1-2015, the time interval range of multiple negative polarity lightning strokes is 10ms-250m, and meanwhile, the counted multiple lightning strokes with the time interval of 100ms in the time intervals of multiple lightning strokes have the largest proportion, and the single time interval of the multiple lightning strokes is determined to be 100ms.
According to the calculated lightning strike frequency of the multiple lightning strikes, the multiple lightning strike frequency of which is 2 is the largest in the lightning strike frequency, so that the lightning strike frequency of the multiple lightning strikes is determined to be 2.
The waveform of the first lightning stroke in the multiple lightning strokes was determined to be 10/350. Mu.s and the waveform of the subsequent lightning stroke was determined to be 0.25/100. Mu.s according to the standard document IEC61312-1 published by the International electrotechnical Commission.
The probability P of each lightning current amplitude is determined by the formula (7), and the lightning current amplitudes of which the P exceeds 50%, 60% and 80% are selected to be 26kA, 19.5kA and 8.5kA respectively.
Thus, referring to FIG. 6, FIG. 6 shows a schematic waveform of multiple lightning strikes of an embodiment of the invention, as shown in FIG. 6, defined as: a single lightning strike interval is less than 0.1s, and a lightning current is composed of one waveform of 10/350 mu s and a plurality of waveforms of 0.25/100 mu s, wherein the amplitude of the lightning current of the first lightning strike is 26kA, 19.5kA and 8.5kA. Wherein the lightning current amplitude of the second lightning stroke is set to 50% of the lightning current amplitude of the first lightning stroke.
After that, construct an inductance Lei Moxing: and obtaining a lightning current Heidler model according to the determined first lightning strike parameters of the multiple lightning strikes, and then constructing an induction lightning model in simulation software based on the lightning channel wave impedance, the circuit element and the lightning current Heidler model.
Setting the time frequency of induction Lei Moxing under multiple lightning strokes as 100ms, setting the parameter Tstrat in a Heidler model of the first lightning stroke as 0s, setting the parameter Tstart in a Heidler model of the subsequent lightning stroke as 100ms to simulate multiple lightning stroke induction mines, obtaining a model measured value, and calculating multiple lightning stroke induction mine overvoltage theoretical values under different lightning current amplitudes according to the lightning stroke parameters of the multiple lightning strokes to obtain the results shown in the following table 1:
TABLE 1 theoretical overvoltage values generated on lightning current on-line compared to model measurements
As can be seen from Table 1, the over-voltage measured value of the inductive lightning model obtained by the embodiment of the invention is close to the amplitude of the theoretical value of the over-voltage of the inductive lightning, and the waveforms are similar, so that the inductive lightning model Lei Moxing can be used for constructing a simulation model.
Then, the volt-ampere characteristics of the arrester were set in AIP-EMTP simulation software to obtain an arrester model, for example, 17kV was taken as rated voltage by taking (YH) HY5WS-17/50 type arrester as an example, and the volt-ampere characteristics were set as shown in Table 2 below.
TABLE 2 volt-ampere characteristics of YH HY5WS-17/50 lightning arresters
And then, obtaining a volt-second characteristic curve of the insulator string through a test, fitting a function expression of the volt-second characteristic curve, writing the function into a MODELS module in ATP simulation software, simulating the P-15 insulator by using the MODELS module, and setting the MODELS module to be conducted and the insulator to be flashover when the voltage curves at the two ends of the insulator are intersected with the volt-second characteristic curve of the insulator in MODELS.
Then, in ATP-EMTP simulation software, tower parameters are set to generate a tower model, specifically comprising the erection height of the tower and the line span of the tower.
Finally, the above models are connected in ATP-EMTP simulation software to obtain an overvoltage simulation model shown in FIG. 7, two groups of time intervals differing by 100ms are simulated, the lightning current waveforms of the lightning current modules are respectively 10/350 mu s and 0.25/100 mu s (induction lightning is taken as an example in the figure), and the most common double lightning strokes in multiple lightning strokes are simulated. The model comprises a 13-base tower, and the line span is 80m. The leftmost side of the model is provided with a 10kV three-phase alternating current power supply, a tower in the middle is provided with a No. #1 tower provided with MOA, and the right side of the No. #1 tower is provided with a No. #2 tower and a No. #3 tower in sequence until reaching a No. #7 tower.
Then, a second lightning stroke parameter is used as a variable to be input into an overvoltage simulation model, wherein the second lightning stroke parameter comprises the first lightning current amplitude value of multiple lightning strokes; in this example, the first lightning current magnitudes of multiple lightning strikes of three intensities are set to be 26kA, 19.5kA, and 8.5kA, respectively; the overvoltage simulation model then outputs the voltages and instantaneous currents across the arrester model for multiple lightning strikes of 26kA, 19.5kA and 8.5 kA. And determining the absorption energy of the lightning arrester model at the macroscopic angle and the absorption energy of the lightning arrester model at the microscopic angle according to the formulas (1) - (6).
Then, respectively comparing the two absorbed energies with the maximum through-flow energy, if one of the two absorbed energies exceeds the maximum through-flow energy, the energy absorbed by the lightning arrester exceeds the threshold value of the energy which can be received by the lightning arrester, so that the lightning arrester is damaged, and the lightning arrester cannot tolerate multiple lightning strokes with corresponding intensity; if the two absorbed energies do not exceed the maximum through-flow energy, the energy absorbed by the lightning arrester does not exceed the threshold value of the energy which can be received by the lightning arrester, the lightning arrester is not damaged, and the lightning arrester can withstand multiple lightning strokes with corresponding intensity.
And finally, comparing a plurality of absorption energies which are smaller than or equal to the maximum through-flow energy, selecting the absorption energy with the largest value as a target absorption energy, and further taking the first lightning current amplitude corresponding to the target absorption energy as a lightning-resistant level threshold of the line. For example, 26kA, 19.5kA and 8.5kA are respectively input to the overvoltage simulation model to obtain three absorption energies, and the three absorption energies obtained by comparison are used as target absorption energies, so that 19.5kA is used as a threshold value of the lightning resistance level of the line, namely the line can bear multiple lightning stroke induction lightning of 19.5kA at maximum energy.
The following describes the determination of the lightning protection level in different installation modes according to an embodiment of the present invention:
The overvoltage simulation model is shown in fig. 7, and lightning arrester models are correspondingly arranged on the #2 tower and the #3 tower of the overvoltage simulation model to the #6 tower of the overvoltage simulation model so as to realize full-line installation. Under the overvoltage simulation model, respectively inputting second lightning stroke parameters with the first lightning stroke lightning current amplitude values of 8.5kA, 19.5kA, 26kA and 56.5kA as input overvoltage simulation models, wherein an induction point for setting induction lightning is positioned on a three-phase conductor of a #1 pole tower in FIG. 7, and a lightning stroke point is positioned on a B-phase conductor of the #1 pole tower in FIG. 7; obtaining an instantaneous current curve and a voltage curve at two ends of a lightning arrester model shown in figures 8-9, and further determining the absorption energy of MOA according to the obtained instantaneous current and the obtained voltage at two ends, and obtaining the energy absorption conditions under a plurality of different lightning current amplitudes of first lightning strokes shown in the following table 3, wherein the absorption energy amplification is the increase proportion of the absorption energy of multiple lightning strokes compared with the absorption energy of single lightning stroke under the same lightning current amplitude; wherein MOA absorbs energy under a single lightning stroke as a control;
TABLE 3 MOA absorption energy under multiple lightning strikes of inductive lightning and single lightning strike
In the embodiment of the invention, the maximum through-flow energy of the lightning arrester is 12300J, and as can be seen from fig. 10 and table 3, in the case of full-line installation, the lightning-proof level of multiple lightning strokes of the lightning arrester is slightly lower than 19.5kA, and the lightning-proof level of single lightning stroke is 56.5kA, and the lightning-proof level of the lightning stroke is reduced by more than 65% compared with the lightning-proof level of single lightning stroke.
The overvoltage simulation model is shown in fig. 7, and the lightning arrester models are correspondingly installed on a #3 pole tower and a #5 pole tower of the overvoltage simulation model so as to realize tower isolation installation. Under the overvoltage simulation model, respectively inputting second lightning stroke parameters with the first lightning stroke lightning current amplitude values of 8.5kA, 19.5kA, 26kA and 59kA as input overvoltage simulation models, wherein induction points for setting induction lightning are positioned on a three-phase conducting wire of a #1 pole tower in FIG. 7, and lightning stroke points are positioned on a B-phase conducting wire of the #1 pole tower in FIG. 7; obtaining the instantaneous current and the voltage at two ends of the lightning arrester, and further obtaining the absorbed energy with the results shown in the following table 4; wherein MOA absorbs energy under a single lightning stroke as a control;
TABLE 4 MOA absorption energy under multiple lightning strikes of inductive lightning and single lightning strike
The maximum through-flow energy of the lightning arrester is 12300J, and as can be seen from the table 4, the lightning-proof level of multiple lightning strokes of the line is 19.5-26 and the lightning-proof level of single lightning stroke is 59kA, the lightning-proof level of the line is reduced by more than 56% compared with the lightning-proof level of the single lightning stroke in the mode of installing a tower; MOA absorbs energy up to 28905J under multiple lightning strikes, which is nearly 135% greater than that of a single lightning strike.
The overvoltage simulation model is shown in fig. 7, the grounding resistance of the tower is changed, and the corresponding lightning current amplitude is adjusted to enable the MOA to reach the maximum energy threshold; the induction point for setting the induction lightning is located on the three-phase conductor of the #1 tower in fig. 7, and the lightning strike point is located on the B-phase conductor of the #1 tower in fig. 7. Taking a grounding resistor 30Ω as an example, the voltage and the instantaneous current at two ends of the MOA under multiple lightning strokes are shown as a graph, so that an instantaneous current curve and a voltage curve at two ends of a lightning arrester model shown as figures 11-12 are obtained, and further the absorption energy of the MOA under multiple lightning strokes is further calculated; wherein, at different ground resistances, the lightning current amplitude when the MOA reaches the energy threshold is as follows in Table 5:
TABLE 5 lightning current amplitude when inductive lightning MOA reaches energy threshold
As can be seen from Table 5, the line lightning resistance level decreases with decreasing ground resistance, wherein the lightning amplitude of multiple lightning strokes is 18.4kA at a ground resistance of 30Ω, and the lightning resistance level is reduced by 56% compared to 42kA at a single stroke.
According to the embodiment, when the lightning stroke is in the form of induction Lei Shi, MOA multiple lightning strokes can absorb energy by 199% or more compared with single lightning stroke MOA, and the lightning resistance level of the line is reduced; when the lightning strike is in the form of a lightning strike wire, MOA multiple lightning strikes can absorb up to 138% of energy compared with single lightning strike MOA, and the lightning resistance level of the line is reduced by 44%. It can be seen that multiple lightning strikes seriously affect the safety of the distribution line;
By comparing the three installation modes, the MOA absorbs energy in a group of installation modes of the base towers, and the phenomenon is lower than that in the case of full line installation, and is more obvious under multiple lightning strokes, so that the mode of installing the distribution line lightning arrester by adopting the tower isolation installation is suggested, the maintenance times can be reduced when the protection effect is the same as that of the full line installation, and the device can be popularized and used in 10kV overhead lines in multiple lightning areas.
When the MOA is installed in a tower separation mode, the protection distance exists to protect the two side towers from flashover and tripping due to line attenuation. Therefore, lightning current will not be diverted via the nearest towers on either side of tower #1, but will instead be directed to the tower where the MOA is installed farther away. It can be seen that the lightning current is in the way of the line traveling further away from the installed MOA towers.
Based on the same inventive concept, the embodiment of the invention also provides a device for calculating the 10kV occurrence lightning-resistant level of the transformer substation taking into consideration the MOA configuration, referring to fig. 13, fig. 13 shows a schematic structural diagram of the device for calculating the 10kV occurrence lightning-resistant level of the transformer substation taking into consideration the MOA configuration, which is provided by the embodiment of the invention, as shown in fig. 13, and the device comprises:
An initialization module 401, configured to generate an overvoltage simulation model in an initializing manner; the overvoltage simulation model comprises an induction Lei Moxing, a lightning arrester model and a pole tower model; the induction Lei Moxing is obtained based on the simulation of a first lightning strike parameter of multiple lightning strikes, and is used for obtaining induction lightning overvoltage, wherein the first lightning strike parameter comprises a plurality of first lightning strike lightning current amplitudes of the multiple lightning strikes, a target waveform and lightning strike frequency; the lightning arrester model is obtained based on simulation of first lightning arrester parameters, the first lightning arrester parameters comprise volt-ampere characteristics of the lightning arrester, and the lightning arrester model is used for simulating the properties of a real lightning arrester; the tower model is obtained based on tower parameter simulation, the tower parameters comprise line span, wire type and tower height, and the tower model is used for simulating the erection position and erection height of a real tower;
The output module 402 is configured to output, in response to a second lightning strike parameter, the first lightning arrester parameter, and the tower parameter that are currently input, a corresponding two-terminal voltage and an instantaneous current when the lightning arrester having a target property is subjected to multiple lightning strikes of different intensities in a target installation manner; wherein, different lightning current amplitude values of the first lightning strike correspond to multiple lightning strikes with different intensities;
A first determining module 403, configured to determine an absorbed energy corresponding to multiple lightning strokes of each intensity based on a voltage at two ends and an instantaneous current corresponding to multiple lightning strokes of multiple intensities;
A second determining module 404, configured to determine a target absorption energy from a plurality of absorption energies based on the maximum through-flow energy; the maximum through-flow energy is the square wave through-flow energy of the lightning arrester within a preset duration;
And a third determining module 405, configured to determine multiple lightning strokes of a target intensity corresponding to the target absorbed energy, and determine a lightning current amplitude of a first lightning stroke of the multiple lightning strokes of the target intensity as a lightning-resistant level threshold of a 10kV outgoing line of the transformer substation.
In some possible embodiments, the first determining module 403 includes: a first determination sub-module for determining a first absorbed energy of the lightning arrester having the target property under multiple lightning strikes of each intensity; wherein the first absorbed energy comprises energy of multiple lightning strokes received by the lightning arrester having the target property and/or an amount of heat absorption by the lightning arrester having the target property;
the first acquisition module is used for acquiring the power frequency freewheel time of the lightning arrester with the target property under multiple lightning strokes of each intensity;
A second determining submodule for determining a second absorption energy of the lightning arrester with the target property based on the power frequency freewheel time, the two-end voltage and the instantaneous current;
a second obtaining module, configured to obtain a heat dissipation capacity of the lightning arrester having the target property based on the second lightning arrester parameter of the lightning arrester having the target property; wherein the second arrester parameters include the number of resistive sheets in the arrester having the target property, specific heat capacity, and mass of each of the resistive sheets;
a third determination submodule for determining a sum of the first absorbed energy and the second absorbed energy as lightning current energy;
and a fourth determination sub-module for determining a difference between the lightning current energy and the heat dissipation capacity as the absorption energy.
In some possible embodiments, the first determining submodule includes: a first determining unit for determining a lightning stroke duration of each lightning stroke in the multiple lightning strokes of each intensity;
A second determining unit for determining energy absorbed by the lightning arrester having the target property at each of multiple lightning strokes based on the lightning stroke duration, the instantaneous current and the terminal voltage;
And a third determining unit, configured to determine, as the first absorbed energy, a sum of energies absorbed by the lightning arresters having the target property corresponding to each of multiple lightning strikes.
In some possible embodiments, the second arrester parameters further include permeability and conductivity of the arrester model, and the first determination submodule further includes: a fourth determining unit for determining a radial flow depth of a surface current of each resistive sheet in the lightning arrester having the target property under multiple lightning strokes of each intensity based on the second lightning arrester parameter and a current frequency of the instantaneous current;
A fifth determining unit for establishing a heat radiation model of the lightning arrester having the target property, and determining an endothermic temperature of each of the resistive sheets according to a finite element calculation method;
A sixth determination unit for determining the first absorbed energy based on the radial flow depth, the second arrester parameter, and the endothermic temperature.
In some possible embodiments, the second acquisition module includes: a seventh determining unit for determining a heat radiation temperature of each of the resistive patches in the lightning arrester model having the target property using a finite element calculation method of electro-thermal-fluidic coupling;
An eighth determination unit configured to determine a heat dissipation capacity of the lightning arrester having the target property based on the second lightning arrester parameter and the heat dissipation temperature.
In some possible embodiments, the initialization module 401 further comprises: a fifth determining submodule, configured to determine the lightning strike time interval based on a counted historical time interval of multiple lightning strikes;
a sixth determining submodule, configured to determine a lightning strike frequency based on a counted historical lightning strike frequency of multiple lightning strikes;
A seventh determining sub-module for determining a waveform of a first lightning strike of a plurality of lightning strikes specified by a lightning protection standard as the target waveform;
The third acquisition module is used for acquiring the first lightning current amplitude values of multiple lightning strokes with different intensities;
The first construction module is used for constructing a lightning current Heidler model based on the lightning strike time interval, the lightning strike frequency, the target waveform and the first lightning strike lightning current amplitude;
And a second construction module, configured to construct the induction Lei Moxing in the simulation software according to a lightning channel wave impedance, a circuit element, and the lightning current Heidler model.
In some embodiments, the third acquisition module comprises: the first acquisition unit is used for acquiring the probability of the lightning current amplitude of the historical first lightning stroke of multiple lightning strokes; a ninth determining unit, configured to determine, from a plurality of the historical first lightning current magnitudes, at least one target first lightning current magnitude with the probability greater than or equal to a preset probability; a tenth determining unit, configured to determine at least one target lightning current amplitude of first lightning strike as the first lightning current amplitude.
For the purposes of simplicity of explanation, the methodologies are shown as a series of acts, but one of ordinary skill in the art will recognize that the present invention is not limited by the order of acts described, as some acts may, in accordance with the present invention, occur in other orders and concurrently. Further, those skilled in the art will recognize that the embodiments described in the specification are all of the preferred embodiments, and that the acts and components referred to are not necessarily required by the present invention.
The method for calculating the 10kV outgoing line lightning resistance level of the transformer substation taking MOA configuration into consideration is described in detail, and specific examples are applied to illustrate the principle and the implementation mode of the method, and the description of the examples is only used for helping to understand the method and the core idea of the method; meanwhile, as those skilled in the art will have variations in the specific embodiments and application scope in accordance with the ideas of the present invention, the present description should not be construed as limiting the present invention in view of the above.
Claims (8)
1. The method for calculating the 10kV outgoing line lightning resistance level of the transformer substation taking MOA configuration into consideration is characterized by comprising the following steps of:
Initializing to generate an overvoltage simulation model; the overvoltage simulation model comprises an induction Lei Moxing, a lightning arrester model and a pole tower model; the induction Lei Moxing is obtained based on the simulation of a first lightning strike parameter of multiple lightning strikes, and is used for obtaining induction lightning overvoltage, wherein the first lightning strike parameter comprises a plurality of first lightning strike lightning current amplitudes of the multiple lightning strikes, a target waveform and lightning strike frequency; the lightning arrester model is obtained based on simulation of first lightning arrester parameters, the first lightning arrester parameters comprise volt-ampere characteristics of the lightning arrester, and the lightning arrester model is used for simulating the properties of a real lightning arrester; the tower model is obtained based on tower parameter simulation, the tower parameters comprise line span, wire type and tower height, and the tower model is used for simulating the erection position and erection height of a real tower;
The overvoltage simulation model responds to the currently input second lightning stroke parameter, the first lightning arrester parameter and the tower parameter, and outputs corresponding two-end voltage and instantaneous current when the lightning arrester with target property is subjected to multiple lightning strokes with different intensities in a target installation mode; wherein, different lightning current amplitude values of the first lightning strike correspond to multiple lightning strikes with different intensities;
Determining the absorption energy corresponding to multiple lightning strokes of each intensity based on the voltages and the instantaneous currents at two ends corresponding to the multiple lightning strokes of the plurality of intensities;
determining a target absorbed energy from a plurality of the absorbed energies based on the maximum through-flow energy; the maximum through-flow energy is the square wave through-flow energy of the lightning arrester within a preset duration;
Determining multiple lightning strokes of target intensity corresponding to the target absorbed energy, and determining the first lightning stroke lightning current amplitude of the multiple lightning strokes of the target intensity as a lightning-resistant level threshold of 10kV outgoing lines of the transformer substation; wherein, based on the voltage and instantaneous current at two ends corresponding to multiple lightning strokes of a plurality of intensities, the absorption energy corresponding to the multiple lightning strokes of each intensity is determined, comprising:
Determining a first absorbed energy of the lightning arrester having the target property under multiple lightning strikes of each intensity; wherein the first absorbed energy comprises energy of multiple lightning strokes received by the lightning arrester having the target property and/or an amount of heat absorption by the lightning arrester having the target property;
acquiring the power frequency freewheel time of the lightning arrester with the target property under multiple lightning strokes of each intensity;
Determining a second absorbed energy of the lightning arrester with target properties based on the power frequency freewheel time, the two-end voltage and the instantaneous current;
acquiring the heat dissipation capacity of the lightning arrester with the target property based on the second lightning arrester parameter of the lightning arrester with the target property; wherein the second arrester parameters include the number of resistive sheets in the arrester having the target property, specific heat capacity, and mass of each of the resistive sheets;
Determining the sum of the first and second absorbed energy as lightning current energy;
and determining the difference between the lightning current energy and the heat dissipation capacity as the absorption energy.
2. The method for calculating 10kV outgoing line lightning resistance level of a substation taking MOA configuration into consideration according to claim 1, wherein in case that the first absorbed energy is energy of multiple lightning strokes received by the lightning arrester with target property, the determining the first absorbed energy of the lightning arrester with target property under each intensity of multiple lightning strokes comprises:
Determining a lightning strike duration of each of the multiple lightning strikes for each intensity;
determining the energy absorbed by the lightning arrester having the target property at each of a plurality of lightning strikes based on the lightning strike duration, the instantaneous current, and the terminal voltage;
And determining the sum of the energy absorbed by the lightning arresters with target properties corresponding to each lightning strike in multiple lightning strikes as the first absorbed energy.
3. The method for calculating 10kV outgoing line lightning resistance level of a substation taking MOA configuration into consideration according to claim 1, wherein the second lightning arrester parameter further comprises magnetic permeability and electrical conductivity of the lightning arrester model; in the case where the first absorbed energy is an amount of heat absorption of the lightning arrester having the target property, the determining the first absorbed energy of the lightning arrester having the target property under each intensity of multiple lightning strokes comprises:
Determining a radial flow depth of surface current for each resistive patch in the arrester having the target property under each intensity of multiple lightning strikes based on the second arrester parameters and the current frequency of the instantaneous current;
establishing a heat dissipation model of the lightning arrester with the target property, and determining the heat absorption temperature of each resistor disc according to a finite element calculation method;
The first absorbed energy is determined based on the radial flow depth, the second arrester parameter, and the endothermic temperature.
4. The method for calculating a 10kV outgoing line lightning resistance level of a substation in consideration of MOA configuration according to claim 1, wherein the obtaining the heat dissipation capacity of the lightning arrester having the target property based on the second lightning arrester parameter comprises:
determining the heat dissipation temperature of each resistance sheet in the lightning arrester model with target properties by adopting an electric-thermal-fluid coupling finite element calculation method;
and determining the heat dissipation capacity of the lightning arrester with the target property based on the second lightning arrester parameter and the heat dissipation temperature.
5. The method for calculating 10kV outgoing line lightning resistance level of a substation taking MOA configuration into account according to claim 1, wherein the first lightning strike parameter further comprises a lightning strike time interval of multiple lightning strikes, and the sensing Lei Moxing is constructed by:
Determining the lightning strike time interval based on the counted historical time interval of multiple lightning strikes;
Determining the lightning strike frequency based on the counted historical lightning strike frequency of multiple lightning strikes;
determining the waveform of the first lightning stroke of multiple lightning strokes specified by lightning protection standards as the target waveform;
Acquiring the first lightning current amplitude values of multiple lightning strokes with different intensities;
Constructing a lightning current Heidler model based on the lightning strike time interval, the lightning strike frequency, the target waveform and the first lightning strike lightning current amplitude;
The induction Lei Moxing is constructed in simulation software based on the lightning channel wave impedance, circuit elements, and the lightning current Heidler model.
6. The method for calculating the lightning withstand level of the 10kV outgoing line of the transformer substation taking the MOA configuration into consideration as claimed in claim 5, wherein the step of obtaining the first lightning current amplitude of multiple lightning strokes with different intensities comprises the following steps:
acquiring the probability of the lightning current amplitude of the historical first lightning stroke of multiple lightning strokes;
Determining at least one target first lightning current amplitude value with the probability larger than or equal to a preset probability from a plurality of historical first lightning current amplitude values;
And determining at least one target first lightning current amplitude as the first lightning current amplitude.
7. The method for calculating the 10kV outgoing line lightning resistance level of the transformer substation taking MOA configuration into consideration as set forth in claim 1, wherein the target installation mode comprises full line installation, tower isolation installation and fixed point installation; the overvoltage simulation model is obtained by connecting the induction lightning model, the lightning arrester model and a plurality of pole tower models, and the lightning arrester model is installed in a line obtained by sequentially connecting the plurality of pole tower models in the target installation mode;
wherein, under the condition that the target installation mode is the full line installation, each group of lightning arrester models is connected at a position corresponding to each tower model;
In the case that the target installation mode is that the tower isolating models are installed, a group of lightning arrester models are installed at intervals, and each group of lightning arrester models is opposite to the position of the tower model;
And under the condition that the target installation mode is the fixed-point installation, installing the lightning arrester model at a position corresponding to one tower model, wherein the circuit is provided with a grounding resistor.
8. The method for calculating the 10kV outgoing line lightning resistance level of the substation taking the MOA configuration into consideration according to claim 1, wherein the determining the target absorption energy from the plurality of absorption energies based on the maximum through-flow energy comprises:
determining at least one candidate absorption energy which is smaller than or equal to the maximum through-flow energy from a plurality of absorption energies;
Comparing the magnitude of the value of the at least one candidate absorbed energy;
And determining the candidate absorption energy with the maximum numerical value as the target absorption energy.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110161304A (en) * | 2019-05-27 | 2019-08-23 | 国网浙江省电力有限公司电力科学研究院 | A kind of multiple thunder acts on the calculation method of lower leakage conductor absorption energy and residual voltage |
| CN110414120A (en) * | 2019-07-24 | 2019-11-05 | 国网湖南省电力有限公司 | A kind of cancellation lightning conducter transmission line of electricity lightning protection properties calculation method |
| CN112054459A (en) * | 2020-07-31 | 2020-12-08 | 广东电网有限责任公司广州供电局 | Lightning protection method for distribution line |
| CN214753194U (en) * | 2021-06-21 | 2021-11-16 | 湖北雷特防雷检测有限公司 | Voltage dependent resistor electrode slice, voltage dependent resistor and lightning protection device |
| CN115098899A (en) * | 2022-06-17 | 2022-09-23 | 华中科技大学 | Multi-lightning risk grading method considering equipment difference and storage medium |
-
2023
- 2023-11-15 CN CN202311525788.3A patent/CN117574711B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110161304A (en) * | 2019-05-27 | 2019-08-23 | 国网浙江省电力有限公司电力科学研究院 | A kind of multiple thunder acts on the calculation method of lower leakage conductor absorption energy and residual voltage |
| CN110414120A (en) * | 2019-07-24 | 2019-11-05 | 国网湖南省电力有限公司 | A kind of cancellation lightning conducter transmission line of electricity lightning protection properties calculation method |
| CN112054459A (en) * | 2020-07-31 | 2020-12-08 | 广东电网有限责任公司广州供电局 | Lightning protection method for distribution line |
| CN214753194U (en) * | 2021-06-21 | 2021-11-16 | 湖北雷特防雷检测有限公司 | Voltage dependent resistor electrode slice, voltage dependent resistor and lightning protection device |
| CN115098899A (en) * | 2022-06-17 | 2022-09-23 | 华中科技大学 | Multi-lightning risk grading method considering equipment difference and storage medium |
Non-Patent Citations (6)
| Title |
|---|
| 10kV线路避雷器直击雷放电电流的影响因素研究;祝达康;司文荣;傅晨钊;王月强;江安烽;傅正财;;电瓷避雷器;20151015(第05期);71-76 * |
| 110kV同塔三回输电线路异常雷击同跳故障机理分析及防护;陆冰冰 等;《水电能源科技》;20181220;第36卷(第12期);182-186 * |
| 多重雷击对线路避雷器的冲击影响研究;廖民传 等;《电瓷避雷器》;20190625(第3期);153-158 * |
| 多重雷击超高压输电线路电磁暂态特性研究;肖宏峰;《中国优秀硕士学位论文全文数据库 工程科技II辑》;20230115(第1期);1-70 * |
| 线路终端杆塔装设避雷器对变电站的保护效果及影响因素;郭婷;周文俊;喻剑辉;;南方电网技术;20150720(第07期);52-56+87 * |
| 线路避雷器的应用及监测;张育华;李凡;桑建平;;电瓷避雷器;20060825(第04期);30-33 * |
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