CN104850738A  Method for calculating lightning induction voltage of overhead power line tower  Google Patents
Method for calculating lightning induction voltage of overhead power line tower Download PDFInfo
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 CN104850738A CN104850738A CN201510214027.5A CN201510214027A CN104850738A CN 104850738 A CN104850738 A CN 104850738A CN 201510214027 A CN201510214027 A CN 201510214027A CN 104850738 A CN104850738 A CN 104850738A
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Abstract
The present invention discloses a method for calculating lightning induction voltage of an overhead power line tower. The method mainly comprises the following steps of: (1) calculating a space lightning electromagnetic field while the influence of the tower is taken into consideration, wherein a subgrid technology based finitedifference timedomain method is adopted in which a coarse mesh is generated for air space and a fine mesh is generated for the tower; (2) applying a twodimensional calculation result of the lightning electromagnetic field to field decomposition of a threedimensional space structure formed by an overhead power line and a lightning current return stroke channel, wherein the lightning electromagnetic field is generated by stimulation of lightning return stroke current; and (3) calculating the lightning induction voltage of the overhead power line and extracting the lightning induction voltage of the tower, wherein the lightning induction voltage of the overhead power line is calculated by using an Agrawal model and an FDTD method, and the tower position is located by grid query and the lightning induction voltage of the tower is extracted. The method can be used for effectively and more accurately estimating the lightning induction voltage of the overhead power line and the lightening induction voltage of insulators and lightning arresters of the tower.
Description
Technical field
The present invention relates to overhead power line lightning protection, Insulation Coordination calculates field, be specially a kind of overhead power transmission line line pole tower place lightning induced voltage computing method.
Background technology
During thunderbolt the earth, the pulse current that thunder and lightning discharges produces strong radiation field by the spatial dimension of thousands of meters.Built on stilts electric line distance, is exposed in the middle of air, is very easily coupled with Lightning Electromagnetic Fields, and form line overvoltage, serious meeting causes linetoground or alternate flashover, damage termination transformer and switchgear etc.Particularly for 35kV and following overhead distribution, because dielectric level is lower, thunder and lightning induction voltage has become line insulation flashover, trip the main cause increased.Correct assessment overhead power line, is particularly positioned at intensity and the timevarying characteristics of the lightning induced voltage that the devices such as the insulator at shaft tower place, lightning arrester bear, for line thunder protection, guarantees that its safe and stable operation is significant.
Existing document is all in the calculating ignoring the situation line thunder and lightning induction voltage that shaft tower affects, and calculated results is existing defects.Because according to the ultimate principle of Electromagnetic Wave Propagation, when the path of Electromagnetic Wave Propagation occurs two kinds of mediums, because electromagnetic parameter is undergone mutation, there will be the phenomenons such as reflection, refraction.Therefore, when Lightning Electromagnetic Fields touches shaft tower, can distort, the induced voltage that such electromagnetic field couples to circuit is formed also changes thereupon.
To calculate overhead power line more accurately and being arranged on the lightning induced voltage that insulator, lightning arrester etc. on shaft tower bear, thus more reasonably carry out Insulation Coordination and lightning Protection Design, be just necessary the impact considering shaft tower.
Summary of the invention
For the problems of the prior art, the invention provides a kind of lightning induced voltage calculating overhead power line when considering that shaft tower affects more exactly and bear, for line wire, Insulator Selection and line insulation matching design provide the overhead power transmission line line pole tower place lightning induced voltage computing method of theoretical foundation, technical scheme of the present invention is as follows: a kind of overhead power transmission line line pole tower place lightning induced voltage computing method, and it comprises the following steps:
101, overhead transmission line lightning current waveform characteristic parameter is led in acquisition more, comprises current peak I
_{0}, wave head time τ
_{1}with wave rear time τ
_{2}, Return stroke speed, attenuation constant, set up substrate lightning current model i
_{s}(0, t) with counterattack passage lightning current i
_{s}the mathematical model of (z', t), wherein substrate lightning current model i
_{s}(0, t) adopt Heidler pattern function:
In formula: I
_{0}for current limit peak value;
for peak point current correction factor; τ
_{1}, τ
_{2}represent wave head, wave rear time respectively.
Fight back passage lightning current i
_{s}the mathematical model of (z', t) adopts improves transmission line model:
i(z',t)＝e
^{λz'}i
_{s}(0,tz'/v
_{i}) t≥z'/v
_{i}(2)
In formula: z ' is lightning channel height; λ is attenuation constant; v
_{i}for lightning current Return stroke speed;
102, obtain the medium parameter of air, shaft tower, be specially aerial DIELECTRIC CONSTANT ε, magnetic permeability μ and conductivityσ; At shaft tower medium dielectric constant microwave medium ε
_{f}, magnetic permeability μ
_{f}and conductivityσ
_{f}.Twodimensional columns coordinate system is set, submesh generation is carried out to zoning, namely coarse grid subdivision is carried out to air section, refined net subdivision is carried out to shaft tower, substitute into the counterattack passage lightning current model i in step 101
_{s}(z', t), according to subgrid FiniteDifference TimeDomain Method and Subgrid FDTD, iterative computation Lightning Electromagnetic Fields;
103, obtain the location parameter of leading overhead transmission line space more, namely in the coordinates computed system of setting, obtain the coordinate position residing for many saddles hollow wire, and the vertical range d of circuit and lightning strike spot, fight back passage threedimensional relationship according to overhead power line and lightning current, the thunder and lightning field component E of gained will be calculated in twodimensional columns coordinate system
_{r}decomposition conversion E is carried out along pole line axis direction
_{x}, in addition, according to leading overhead transmission line space position parameter, calculate unit length inductance coefficent matrix L corresponding to many saddles ceases to be busy and capacitance per unit length matrix of coefficients C more;
104, the thunder and lightning electric field component obtained according to step 103 is along the decomposition computation result of overhead transmission line axis, and unit length inductance coefficent matrix L and capacitance per unit length matrix of coefficients C, and input overhead transmission line top and terminal equivalent impedance, overhead transmission line length, calculate thunder and lightning electric field to the Agrawal model of electromagnetic coupled of leading overhead power line more, form the equation for transmission line group containing distribution power;
105, by overhead transmission line in the xdirection with step delta x subdivision, time discrete steplength gets Δ t, can obtain the iterative computation formula of lightning induced voltage on circuit
In formula:
with
represent that (n+1) Δ t line length is induction current row phasor and the scattering voltage vector at k Δ x place respectively;
Obtain overhead transmission line top and terminal equivalent impedance, revise the boundary
In formula:
with
represent that (n+1) Δ t line length is induction current row phasor and the scattering voltage vector at k Δ x place respectively; Z
_{s}and Z
_{l}be respectively circuit top and terminal termination impedance vector;
for the horizontal component vector of wire place incident electric fields;
with
be respectively the vertical component vector of circuit top and terminal location incident electric fields;
106, the lightning induced voltage on circuit is asked, i.e. scattering voltage and incident voltage sum
Then according to overhead transmission line startstop position, span, shaft tower and circuit top distance, mesh generation step information, determine the computing grid number that shaft tower position is corresponding, extract and export the lightning induced voltage at shaft tower place.
Further, adopt coarse grid and refined net to carry out division to twodimentional Lightning Electromagnetic Fields in step 102 and calculate, concrete steps be:
The spatial mesh size of A, coarse grid and time step are selected; Δ l
_{max}< λ
_{min}/ 10,
In formula: Δ l
_{max}for the maximum space steplength of grid; λ
_{min}for the electromagnetic minimum wavelength of thunder and lightning;
The selection gist Courant numerical stability condition of time step
The spatial mesh size of B, refined net and time step are selected;
A coarse grid is made n
_{f}decile, then the spatial mesh size of refined net is
The time step of refined net is
C, the discrete Maxwell equation of employing central difference are to the iterative computation of Lightning Electromagnetic Fields component on coarse grid;
D, iterative computation based on Lightning Electromagnetic Fields component on the refined net of subcellFDTD method.
Further, in step C, adopt the discrete Maxwell equation of central difference, obtain the FDTD iterative computation formula of Lightning Electromagnetic Fields in space
In formula: i, j are respectively the grid number on r direction and z direction, n is iteration time step number; ε
_{c}, μ
_{c}and σ
_{c}be respectively the specific inductive capacity of air, magnetic permeability and conductivity.
And lightning current fights back the E on passage
_{z}need to do special process:
In formula:
represent (n+1) Δ t, be highly
the counterattack passage lightning current size at place.
Further, subcellFDTD method is adopted to be specially the iterative computation of Lightning Electromagnetic Fields component on refined net in step D:
D1, carry out refined net subdivision in shaft tower position, an original coarse grid is made n
_{f}decile,
e
_{rf}and E
_{zf}represent that the Lightning Electromagnetic Fields on refined net exists
component on direction;
D2, from the propelling in n → n+1 moment, n is divided into refined net
_{f}individual little time step carries out, and namely the field component of refined net inside calculates and carries out n
_{f}secondary loop iteration calculates, and iterative computation formula is
In formula: ii, jj are respectively the refined net number on r direction and z direction, m is refined net inner iteration time step number; ε
_{f}, μ
_{f}and σ
_{f}be respectively the specific inductive capacity of shaft tower dielectric material, magnetic permeability and conductivity.
Further, also comprise by the calculation procedure of method of interpolation to the field component at coarse grid and fine grid coincidence boundary place in steps d 2, be specially and utilize n moment and n+1 moment known field component value and refined net time iteration step number to carry out interpolation, interpolation need meet wave equation
In formula: D represents E
_{r}, E
_{z}or
one of them; V is velocity of wave.
Advantage of the present invention and beneficial effect as follows:
The present invention proposes the FiniteDifference TimeDomain Method (FDTD) based on subcell technique, the theoretical method of the lightning induced voltage that overhead power line is formed is calculated when consideration shaft tower affects, so both can obtain result of calculation more accurately, and reduce again calculated amount as far as possible, save computing time.
The present invention also proposes to be decomposed by thunder and lightning field component, Lightning Electromagnetic Fields two dimension result of calculation is applied to the technical method of overhead transmission line and lightning channel threedimensional structure fieldline coupling calculating, reaches the object simplifying and calculate, raise the efficiency.Abovementioned main points compensate for the blank of existing theoretical research.
Accompanying drawing explanation
Fig. 1 is preferred embodiment of the present invention overhead power transmission line line pole tower place lightning induced voltage calculation flow chart;
Fig. 2 is that Lightning Electromagnetic Fields calculates coarse grid subdivision schematic diagram;
Fig. 3 is that Lightning Electromagnetic Fields calculates refined net subdivision schematic diagram;
Fig. 4 is subgrid FDTD calculation procedure realization flow figure;
Fig. 5 is by E
_{r}be decomposed into E
_{x}coordinate and grid arrange;
Fig. 6 is Lightning Electromagnetic Fields and the Agrawal model of leading overhead transmission line more and being coupled.
Embodiment
Below in conjunction with accompanying drawing, the invention will be further described:
1. the Lightning Electromagnetic Fields based on FDTD subcell technique calculates
Illustrate: in view of the transient characteristic of Lightning Electromagnetic Fields, select FiniteDifference TimeDomain Method (FDTD) to calculate; Further, because need the tower structure considering small scale in the computation process of largescale dimension electromagnetic field, therefore have employed the subcell technique of FDTD.
1.1 obtain lightning current waveform characteristic parameter, comprise current peak, wave head time and wave rear time, Return stroke speed, attenuation constant etc., set up substrate lightning current model i
_{s}(0, t) with counterattack passage lightning current i
_{s}the mathematical model of (z', t).
Substrate lightning current recommendation Heidler pattern function:
In formula: I
_{0}for current limit peak value;
for peak point current correction factor; τ
_{1}, τ
_{2}for limiting wave head, wave rear time.
Fight back passage lightning current recommendation and improve transmission line model:
i(z',t)＝e
^{λz'}i
_{s}(0,tz'/v
_{i}) t≥z'/v
_{i}(2)
In formula: z ' is lightning channel height; λ is attenuation constant; v
_{i}for lightning current Return stroke speed.
The medium parameter of 1.2 acquisition air, shaft tower, is specially respective DIELECTRIC CONSTANT ε, magnetic permeability μ and conductivityσ.
The spatial mesh size of 1.3 coarse grids and time step are selected
When utilizing FDTD method to carry out the calculating of homogeneous space Lightning Electromagnetic Fields, can suitably get under the prerequisite of yardstick stability requirement formula (3) Suo Shi of mesh generation greatly a bit, this kind of grid is called coarse grid.The too small meeting of grid caused intensive, had a strong impact on counting yield.
Δl
_{max}＜λ
_{min}/10 (3)
In formula: Δ l
_{max}for the maximum space steplength of grid; λ
_{min}for the electromagnetic minimum wavelength of thunder and lightning.
Meanwhile, the selection gist Courant numerical stability condition of time step
In formula: c
_{max}for maximum velocity of wave; Δ x, Δ y, Δ z are the steplength of grid on x, y, z three directions.
Lightning Electromagnetic Fields is propagated in atmosphere, and gets Δ x=Δ y=Δ z=Δ l when calculating
_{c}, then time step stability condition abbreviation is
In formula: c is the light velocity.
The spatial mesh size of 1.4 refined nets and time step are selected
Because shaft tower tower body diameter compares the step delta l of coarse grid
_{c}much smaller, as the impact of shaft tower on Lightning Electromagnetic Fields will be embodied, carry out fine dissection with regard to needs in shaft tower position.
A coarse grid is supposed to make n
_{f}decile, then the spatial mesh size of refined net is
The time step of refined net is
The iterative computation of Lightning Electromagnetic Fields component on 1.5 coarse grids
Thunderbolt the earth or buildings after Fields of Lightning Return Stroke electric current formed electromagnetic field, the space distribution of Lightning Electromagnetic Fields, therefore can calculate for rotational symmetry distributes with lightning current passage in twodimensional columns coordinate system.
Meet Δ l
_{max}, Δ t
_{c}requirement in twodimensional columns coordinate system, carry out mesh generation, as shown in Figure 2, wherein E
_{r}, E
_{z}with
represent the electromagnetic field component on coarse grid.
The sampling of electric field component and magneticfield component is respectively
with
adopt the discrete Maxwell equation of central difference, the FDTD iterative computation formula of Lightning Electromagnetic Fields in space can be obtained
In formula: i, j are respectively the grid number on r direction and z direction, n is iteration time step number; ε
_{c}, μ
_{c}and σ
_{c}be respectively the specific inductive capacity of air, magnetic permeability and conductivity.
Lightning current fights back the E on passage
_{z}need to do special process:
In formula:
represent (n+1) Δ t, be highly
the counterattack passage lightning current size at place.
The iterative computation of Lightning Electromagnetic Fields component on 1.6 refined nets
Carry out refined net subdivision in shaft tower position, as shown in Figure 3 an original coarse grid is made n
_{f}decile, (with n
_{f}=3 is example).
e
_{rf}and E
_{zf}represent the field component on refined net.
In FDTD calculates, adjacent 4 electric field components are used in the calculating of magneticfield component, and adjacent 2 magneticfield components are used in the calculating of electric field component, and this is not only applicable to coarse grid, is equally applicable to refined net.
Further, n need be divided into refined net from the propelling in n → n+1 moment
_{f}individual little time step carries out, and namely the field component of refined net inside calculates and need carry out n
_{f}secondary loop iteration calculates, and iterative computation formula is
In formula: ii, jj are respectively the refined net number on r direction and z direction, m is refined net inner iteration time step number; ε
_{f}, μ
_{f}and σ
_{f}be respectively the specific inductive capacity of shaft tower dielectric material, magnetic permeability and conductivity.
The field component at direct calculating coarse grid and fine grid coincidence boundary place needs and nonexistent refined net field component, and the method solving this problem utilizes n moment and n+1 moment known field component value and refined net time iteration step number, solved by method of interpolation.Interpolation need meet wave equation
In formula: D represents E
_{r}, E
_{z}or
one of them; V is velocity of wave.
Based on FDTD subcell technique Lightning Electromagnetic Fields calculation procedure realization flow as shown in Figure 4.
2. the decomposition computation of electric field component in overhead transmission linelightning channel threedimensional structure
(illustrate: under normal circumstances, the locus of overhead power line and lightning channel is threedimensional structure, in order to avoid complicated and loaded down with trivial details threedimensional lightning Electromagnetic Calculation, improve counting yield, the field component calculated can be carried out decomposition conversion in twodimensional columns coordinate system.)
Overhead transmission line space position parameter is led in 2.1 acquisitions more, namely in the coordinates computed system of setting, and the coordinate position residing for many saddles hollow wire, and the vertical range d etc. of circuit and lightning strike spot.
2.2 set overhead transmission line axially as x direction, and carry out mesh generation to aerial condutor, steplength gets Δ x.
2.3 are illustrated in figure 5 and calculate gained E by twodimensional columns coordinate system
_{r}be decomposed into E
_{x}time the coordinate that uses and grid arrange.Conversion relational expression meets
In formula: i is r direction grid number; K is x direction grid number.
3., lead overhead power line and the calculating of insulator lightning induced voltage more
3.1, according to leading overhead transmission line space position parameter, calculate unit length inductance coefficent matrix L corresponding to many saddles ceases to be busy and capacitance per unit length matrix of coefficients C more.Wherein, C=P
^{1}
P for leading the corresponding coefficient of potential matrix of overhead transmission line more, and be n rank square formation, n is number of lead wires.Element in matrix can be tried to achieve according to image method:
In formula: ε
_{0}for permittivity of vacuum; h
_{i}and R
_{i}be respectively the liftoff vertical range of i wire and radius; L
_{ij}and L'
_{ij}be respectively i wire and image conductor thereof the distance to j wire.
Overhead power line is approximate can be considered lossless line, then
L＝μ
_{0}ε
_{0}P (15)
In formula: μ
_{0}for permeability of vacuum.
3.2, according to calculating thunder and lightning electric field to the Agrawal model (as shown in Figure 6) of electromagnetic coupled of leading overhead power line, form the equation for transmission line group containing distribution power more:
In formula: u
^{sca}(x, t) is scattering voltage; I (x, t) is the induction current in circuit; E
_{x}(x, h, t) is for incident electric fields is in the horizontal component at wire place.
3.3 by overhead transmission line in the xdirection with step delta x subdivision, time discrete steplength gets Δ t, with the local derviation in center difference coefficient approximate treatment formula (14), can obtain the iterative computation formula of lightning induced voltage on circuit
In formula:
with
represent that (n+1) Δ t line length is induction current row phasor and the scattering voltage vector at k Δ x place respectively.
Obtain overhead transmission line top and terminal equivalent impedance, revise the boundary
In formula:
with
represent that (n+1) Δ t line length is induction current row phasor and the scattering voltage vector at k Δ x place respectively; Z
_{s}and Z
_{l}be respectively circuit top and terminal termination impedance vector;
for the horizontal component vector of wire place incident electric fields;
with
be respectively the vertical component vector of circuit top and terminal location incident electric fields.
Lightning induced voltage on 3.4 circuits is scattering voltage and incident voltage sum
3.5, according to information such as overhead transmission line startstop position, span, shaft tower and circuit top distance, mesh generation steplengths, determine the computing grid number that shaft tower position is corresponding, extract and export the lightning induced voltage at shaft tower place.
These embodiments are interpreted as only being not used in for illustration of the present invention limiting the scope of the invention above.After the content of reading record of the present invention, technician can make various changes or modifications the present invention, and these equivalence changes and modification fall into the scope of the claims in the present invention equally.
Claims (5)
1. overhead power transmission line line pole tower place lightning induced voltage computing method, is characterized in that, comprise the following steps:
101, overhead transmission line lightning current waveform characteristic parameter is led in acquisition more, comprises current peak I
_{0}, wave head time τ
_{1}with wave rear time τ
_{2}, Return stroke speed, attenuation constant, set up substrate lightning current model i
_{s}(0, t) with counterattack passage lightning current i
_{s}the mathematical model of (z', t), wherein substrate lightning current model i
_{s}(0, t) adopt Heidler pattern function:
In formula: I
_{0}for current limit peak value;
for peak point current correction factor; τ
_{1}, τ
_{2}represent wave head, wave rear time respectively;
Fight back passage lightning current i
_{s}the mathematical model of (z', t) adopts improves transmission line model:
i(z',t)＝e
^{λz'}i
_{s}(0,tz'/v
_{i}) t≥z'/v
_{i}
In formula: z ' is lightning channel height; λ is attenuation constant; v
_{i}for lightning current Return stroke speed;
102, obtain the medium parameter of air, shaft tower, be specially aerial DIELECTRIC CONSTANT ε, magnetic permeability μ and conductivityσ; At shaft tower medium dielectric constant microwave medium ε
_{f}, magnetic permeability μ
_{f}and conductivityσ
_{f}; Twodimensional columns coordinate system is set, submesh generation is carried out to zoning, namely coarse grid subdivision is carried out to air section, refined net subdivision is carried out to shaft tower, substitute into the counterattack passage lightning current model i in step 101
_{s}(z', t), according to subgrid FiniteDifference TimeDomain Method and Subgrid FDTD, iterative computation Lightning Electromagnetic Fields;
103, obtain the location parameter of leading overhead transmission line space more, namely in the coordinates computed system of setting, obtain the coordinate position residing for many saddles hollow wire, and the vertical range d of circuit and lightning strike spot, fight back passage threedimensional relationship according to overhead power line and lightning current, the thunder and lightning field component E of gained will be calculated in twodimensional columns coordinate system
_{r}carry out decomposition along pole line axis direction and be converted to E
_{x}, in addition, according to leading overhead transmission line space position parameter, calculate unit length inductance coefficent matrix L corresponding to many saddles ceases to be busy and capacitance per unit length matrix of coefficients C more;
104, the thunder and lightning electric field component obtained according to step 103 is along the decomposition computation result of overhead transmission line axis, and unit length inductance coefficent matrix L and capacitance per unit length matrix of coefficients C, and input overhead transmission line top and terminal equivalent impedance, overhead transmission line length, calculate thunder and lightning electric field to the Agrawal model of electromagnetic coupled of leading overhead power line more, form the equation for transmission line group containing distribution power;
105, by overhead transmission line in the xdirection with step delta x subdivision, time discrete steplength gets Δ t, can obtain the iterative computation formula of lightning induced voltage on circuit
In formula:
with
represent that (n+1) Δ t line length is induction current row phasor and the scattering voltage vector at k Δ x place respectively;
Obtain overhead transmission line top and terminal equivalent impedance, revise the boundary
In formula:
with
represent that (n+1) Δ t line length is induction current row phasor and the scattering voltage vector at k Δ x place respectively; Z
_{s}and Z
_{l}be respectively circuit top and terminal termination impedance vector;
for the horizontal component vector of wire place incident electric fields;
with
be respectively the vertical component vector of circuit top and terminal location incident electric fields;
106, the lightning induced voltage on circuit is asked, i.e. scattering voltage and incident voltage sum
Then according to overhead transmission line startstop position, span, shaft tower and circuit top distance, mesh generation step information, determine the computing grid number that shaft tower position is corresponding, extract and export the lightning induced voltage at shaft tower place.
2. a kind of overhead power transmission line line pole tower place according to claim 1 lightning induced voltage computing method, is characterized in that, adopt coarse grid and refined net to carry out division to twodimentional Lightning Electromagnetic Fields and calculate in step 102, concrete steps be:
The spatial mesh size of A, coarse grid and time step are selected; △ l
_{max}< λ
_{min}/ 10,
In formula: △ l
_{max}for the maximum space steplength of grid; λ
_{min}for the electromagnetic minimum wavelength of thunder and lightning;
The selection gist Courant numerical stability condition of time step
The spatial mesh size of B, refined net and time step are selected;
A coarse grid is made n
_{f}decile, then the spatial mesh size of refined net is
The time step of refined net is
C, the discrete Maxwell equation of employing central difference are to the iterative computation of Lightning Electromagnetic Fields component on coarse grid;
D, iterative computation based on Lightning Electromagnetic Fields component on the refined net of subcellFDTD method.
3. a kind of overhead power transmission line line pole tower place according to claim 2 lightning induced voltage computing method, is characterized in that, adopt the discrete Maxwell equation of central difference in step C, obtain the FDTD iterative computation formula of Lightning Electromagnetic Fields in space
In formula: i, j are respectively the grid number on r direction and z direction, n is iteration time step number; ε
_{c}, μ
_{c}and σ
_{c}be respectively the specific inductive capacity of air, magnetic permeability and conductivity;
And lightning current fights back the E on passage
_{z}:
In formula:
represent (n+1) △ t, be highly
the counterattack passage lightning current size at place.
4. a kind of overhead power transmission line line pole tower place according to claim 2 lightning induced voltage computing method, is characterized in that, adopt subcellFDTD method to be specially the iterative computation of Lightning Electromagnetic Fields component on refined net in step D:
D1, carry out refined net subdivision in shaft tower position, an original coarse grid is made n
_{f}decile,
e
_{rf}and E
_{zf}represent that the Lightning Electromagnetic Fields on refined net exists
component on r, z direction;
D2, from the propelling in n → n+1 moment, n is divided into refined net
_{f}individual little time step carries out, and namely the field component of refined net inside calculates and carries out n
_{f}secondary loop iteration calculates, and iterative computation formula is
In formula: ii, jj are respectively the refined net number on r direction and z direction, m is refined net inner iteration time step number; ε
_{f}, μ
_{f}and σ
_{f}be respectively the specific inductive capacity of shaft tower dielectric material, magnetic permeability and conductivity.
5. a kind of overhead power transmission line line pole tower place according to claim 4 lightning induced voltage computing method, it is characterized in that: also comprise by the calculation procedure of method of interpolation to the field component at coarse grid and fine grid coincidence boundary place in steps d 2, be specially and utilize n moment and n+1 moment known field component value and refined net time iteration step number to carry out interpolation, interpolation need meet wave equation
In formula: D represents E
_{r}, E
_{z}or
one of them; V is velocity of wave.
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Cited By (5)
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CN105426671A (en) *  20151111  20160323  重庆大学  Method for evaluating reliability of overhead power distribution line in thunderstorm weather 
CN106124830A (en) *  20160711  20161116  清华大学  The method obtaining lightning current based on artificial neural network 
CN107845141A (en) *  20171127  20180327  山东大学  A kind of transient electromagnetic threedimensional FDTD forward modeling multiresolution meshes subdivision methods 
CN108037373A (en) *  20171207  20180515  南方电网科学研究院有限责任公司  The detection method and system of Electromagnetic Fields of Lightning Return Stroke 
CN108363899A (en) *  20180517  20180803  陕西省地方电力（集团）有限公司  A kind of distribution lightning induced voltage appraisal procedure and system 
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CN103714239A (en) *  20131115  20140409  贵州电力试验研究院  Method for computing lightning induced voltages of insulators of lowvoltage lines when earth is struck by lightning 
CN103984992A (en) *  20140512  20140813  重庆大学  Prediction method of multiloop alternatingcurrent electric transmission line crisscross area resultant magnetic field 

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CN105426671A (en) *  20151111  20160323  重庆大学  Method for evaluating reliability of overhead power distribution line in thunderstorm weather 
CN105426671B (en) *  20151111  20180216  重庆大学  The reliability evaluating method of overhead distribution under a kind of Thunderstorm Weather 
CN106124830A (en) *  20160711  20161116  清华大学  The method obtaining lightning current based on artificial neural network 
CN107845141A (en) *  20171127  20180327  山东大学  A kind of transient electromagnetic threedimensional FDTD forward modeling multiresolution meshes subdivision methods 
CN107845141B (en) *  20171127  20181127  山东大学  A kind of transient electromagnetic threedimensional FDTD forward modeling multiresolution meshes subdivision method 
CN108037373A (en) *  20171207  20180515  南方电网科学研究院有限责任公司  The detection method and system of Electromagnetic Fields of Lightning Return Stroke 
CN108037373B (en) *  20171207  20200331  南方电网科学研究院有限责任公司  Method and system for detecting lightning return stroke electromagnetic field 
CN108363899A (en) *  20180517  20180803  陕西省地方电力（集团）有限公司  A kind of distribution lightning induced voltage appraisal procedure and system 
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