CN112749500B - Estimation method for lightning induction overvoltage of wind power plant collector line in high-altitude mountain area - Google Patents
Estimation method for lightning induction overvoltage of wind power plant collector line in high-altitude mountain area Download PDFInfo
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Abstract
The invention discloses an estimation method of lightning induction overvoltage of a collecting line of a wind power plant in a high-altitude mountain area, and belongs to the field of lightning protection of the collecting line of the wind power plant. According to the lightning current attenuation method, a lightning current attenuation model of the lightning fan is firstly established, the lightning electromagnetic field is calculated by equivalent of a tower barrel of the fan body into a vertical conductor, then the transient response of the collecting circuit under the excitation of the lightning electromagnetic field is calculated, and the lightning induced overvoltage calculating method of the collecting circuit considering the ground loss is provided, so that the calculating result is combined with reality more accurately. According to the method, when the induced overvoltage of the current collecting line is calculated, the influence of multiple refraction and reflection generated by the lightning stroke fan on the tower barrel is considered, the vertical conductor of the tower barrel is equivalent, the field line coupling model considering the ground loss is adopted, so that the model is closer to the actual situation, finally, the difficulty of lightning electromagnetic transient modeling of the current collecting line is reduced through the FDTD method, and the calculation of the induced overvoltage of the current collecting line is more accurate.
Description
Technical Field
The invention belongs to the field of lightning protection of a collecting line of a high-altitude wind power plant, and particularly relates to an estimation method of lightning induction overvoltage of a collecting line of a wind power plant in a high-altitude mountain area.
Background
The wind power plant collector line fault caused by lightning is one of the main reasons for influencing the safe and reliable power supply of the wind power plant collector line. Based on a special energy utilization mode of the wind farm, the wind turbine is in a relatively special geographic environment: high altitude, strong wind speed, high humidity, high soil resistivity, frequent lightning activity, etc. Based on special topography condition in mountain area, the barriers such as trees, mountain and the like are more for wind farm 35kV transmission line tower establishes the high approximately 110kV pole tower height, however, thunder overvoltage protection still designs according to 35kV circuit, and the protective capability does not promote, thereby lightning induction overvoltage that ground or high-point building produced near the thunderbolt circuit will cause the circuit to take place the flashover. Aiming at the problem, some work is carried out in China on the aspect of generating overvoltage research on a current collecting circuit by lightning strike, but the specificity of a mountain wind power plant is ignored, and as part of fans are very close to a terminal tower, the heights of the fans are far higher than those of the tower of the current collecting circuit; therefore, it is necessary to establish a model that the actual lightning stroke fan generates the back striking current in the tower, and further calculate the numerical solution of the induced overvoltage generated by the current collecting circuit.
The electric transmission line induction overvoltage is researched in literature (improved Agrawal model and FDTD method-based induced lightning overvoltage algorithm) (high voltage technology (2019, 11 th period), power distribution line induction overvoltage calculation method based on PSCAD/EMTDC (CN 103399190B) and power distribution line induction overvoltage calculation method based on combination of field paths (CN 109711088A), but the electric transmission line induction overvoltage is researched in such a way that the influence of lightning strike on a wire caused by the ground is concentrated, the situation that the attraction of mountain buildings and fans on the lightning is greatly higher than the ground in a mountain wind power plant in mountain areas is not considered, and the situation that the calculation and analysis of the electric power plant current collection line induction overvoltage is inconsistent with the actual situation is further considered.
In summary, the following problems exist in the prior art:
1) Based on the complicated topography structure condition of mountain areas, the high-point buildings such as mountain bodies, fans and the like are more practical than lightning grounds, so that the research on the condition of the lightning high-point buildings has more practical significance.
2) The traditional national standard calculation formula in China is relatively accurate and reasonable in calculation of the induction overvoltage amplitude, but actual conditions and lightning stroke back striking processes are not considered, so that larger errors exist in calculation results.
3) Considering the complex situation of the topography of the high-altitude mountain area, simulating lightning strike to the ground or accurately solving the induced overvoltage of the wind power plant collector line lead by the high-point building has great difficulty.
Therefore, an estimation method capable of considering the lightning stroke simulation fans in the high-altitude mountain areas to calculate the induction overvoltage of the collecting line is required to be provided, and a scientific analysis means is provided for accurately calculating the induction overvoltage of the collecting line of the wind power plant.
Disclosure of Invention
Aiming at the technical problems that a wind power plant in China is built in mountainous areas, the height of a fan body to the ground is high, lightning leading capability is high, so that a flashover problem is easy to occur to a tower insulator at the terminal end of a collecting line near the fan, a space electromagnetic field distribution condition is solved by building a back-striking current model of a lightning stroke fan, a field line coupling calculation model of the induction overvoltage of the collecting line is built, and finally an FDTD (finite difference time domain method) is adopted to solve an estimation method of the induction overvoltage of the collecting line.
The invention aims to realize the estimation method, which is provided by the invention, of the lightning induction overvoltage of the wind power plant collector line in the high altitude mountain area, and comprises the following steps:
step 1, setting current collecting circuit information of a wind power plant;
sampling wind power plant collecting line information required to be subjected to induction overvoltage calculation to obtain the following wind power plant collecting line information: lightning current peak value I, lightning back striking channel height H, fan tower vertical height H, current collecting line wire pair average vertical height H a ；
Step 2, calculating the back-striking current i (z', t) of the lightning stroke fan;
in calculating the back-striking current of a lightning stroke fan, the following basic assumption is made:
1) The lightning striking back channel is perpendicular to the ground and is formed by connecting infinite current elements in vertical orientation;
2) The back-striking current of the lightning stroke fan propagates upwards along the lightning back-striking channel at a speed v;
in the lightning strike back channel, any vertical height is taken and recorded as vertical height z ', strike back current i (z ', t) at the vertical height z ' is calculated, wherein t is time;
when z '. Gtoreq.h, the strike back current i (z ', t) at the vertical height z ' is expressed as follows:
when 0.ltoreq.z ' < h, the strike back current i (z ', t) at the vertical height z ' is expressed as follows:
wherein:
t is the development time of lightning current, m is the current gradient factor, lambda is the current attenuation constant, q is the reflection times of lightning current at two ends of a high tower, c is the speed of light, v is the propagation speed of back-striking current, and ρ top As the top current reflection coefficient ρ bot Is the bottom current reflection coefficient;
u is the sea-going function, whenFor, u=1; when->For, u=0;
η is the peak value correction coefficient and,τ 1 is wave-shapedHead time constant τ 2 Is the wave tail time constant;
step 3, establishing a lightning back-striking electromagnetic field calculation model considering the earth loss;
step 3.1, calculating a spatial electromagnetic field generated by the back-striking current by using maxwell's equations under the condition that the ideal conductor is earth, comprising: axial magnetic fieldHorizontal electric field E r (r, z, t) and vertical electric field E z (r, z, t) whose maxwell equations are expressed as follows:
wherein: r is the radial coordinate of the space electromagnetic field, z is the vertical height of any observed point in the space electromagnetic field and is recorded as the height z epsilon 0 Is vacuum dielectric constant; r is the linear distance of the current dipole to the point where the space is observed,R 1 for the linear distance of the mirror current to the point of the space to be observed, +.> For at vertical height z', timeIs->The value of the return current at the moment; />For a vertical height z', time +.>The value of the return current at the moment;for a vertical height z', time +.>Differentiating the back-striking current of the moment with respect to time;for a vertical height z', time +.>Differentiating the back-striking current of the moment with respect to time;
step 3.2, establishing a horizontal electric field E taking into account the ground loss rg The frequency domain calculation correction equation for (r, z, jω) is as follows:
wherein: e (E) r (r, z, jω) is a Fourier transform of the horizontal component of the electric field at a height z,sigma, a form of fourier transformation of the azimuthal component of the magnetic field at the surface g For earth conductivity, epsilon rg Mu, relative dielectric constant to earth 0 The geomagnetic conductivity is the geomagnetic conductivity, ω is the frequency, and j is the imaginary part;
step 4, establishing a coupling calculation model of the electromagnetic field excited by the lightning back-striking electromagnetic field and the transmission line;
step 4.1, when the earth and line loss are considered, a transmission line Agrawal model under electromagnetic excitation of lightning return stroke is established, and the expression is as follows:
wherein: u (u) s (x, t) is the lightning induced voltage scattering voltage component of the wind power plant collector line conductor, s is the sign of the induced voltage scattering voltage component, x is the argument, i (x, t) is the lightning induced current of the wind power plant collector line conductor, [ L ]]Inductance matrix for unit length of transmission line, [ C ]]For a matrix of capacitances per unit length of transmission line, E r (x，H a T) is the lightning back-striking electric field strength in the direction of the conductor at the height of the conductor of the wind power plant current collecting circuit, and ζ g (t- τ) is a transient earth impedance matrix, τ is an intermediate variable of time;
wherein mu 0 Is the vacuum magnetic permeability coefficient; epsilon 0 Is vacuum dielectric constant; epsilon rg Is the relative dielectric constant; erfc is the function of the error,
step 4.2, solving an induced voltage vector u (x, t) on the current collecting line conductor, wherein the expression is as follows:
step 5, carrying out Agrawal model numerical solution of the current collecting line wires by adopting a time domain finite difference method to obtain induced overvoltage values of the current collecting lines of the wind power plant;
firstly, calculating the induction scattering voltage of the head end of a transmission lineInduced scattering voltage with transmission line endThe expression is as follows:
wherein: g is a matching resistor, Δx is a space step, Δt is a time step, n is an integer representing a time step, n=0, 1,2 … NDT, NDT is a maximum time step integer, k is an integer representing a space step, k=0, 1,2 … NDX, NDX is a maximum space step integer;is the scattering voltage at the time of n delta t at the head end of the transmission line; />Is the scattering voltage at the end of the transmission line at the time nΔt; />For being positioned +.>Department(s),>the induced current at the moment; />To be positioned atDepartment(s),>the induced current at the moment; />Is the vertical electric field at the moment nDeltat at the vertical height z at the head end of the transmission line, +.>A vertical electric field at a vertical height z, at the end of the transmission line, at time nΔt; />Is a vertical electric field at the (n+1) deltat moment at the vertical height z at the head end of the transmission line; />A vertical electric field at a vertical height z, (n+1) Δt at the end of the transmission line;
next, the portions other than the head end and the tail end of the collector line are referred to as a middle portion, any one of the middle portions is denoted as k, k=1, 2 … NDX-1, and the induced scattering voltage at k is obtainedThe expression is as follows:
wherein:for being positioned +.>Department(s),>time-of-day induced current, ">For being positioned +.>Department(s),>time-of-day induced current, ">Is the induced voltage at kΔx, at nΔt;
finally, the induced current is calculatedThe expression is as follows:
wherein: zeta type toy g In the form of a transient earth impedance matrix,for being positioned +.>Department(s),> time horizontal electric field, ">For being positioned +.>Department(s),>the horizontal electric field at the moment in time,for being positioned +.>Department(s),>time-of-day induced current, ">For being positioned +.>Department(s),>the induced current at the moment.
Compared with the prior art, the invention has the following beneficial effects:
1. compared with the traditional condition of simulating lightning to calculate the induced overvoltage in the ground, the method mainly analyzes the induced overvoltage condition of the lightning fan generated by the current collecting line lead, so that the induced overvoltage research in the high-altitude mountain area is more practical.
2. Considering the complex structure of the wind turbine tower, the wind turbine tower is equivalent to a vertical conductor, and a back-striking model of the lightning channel in the wind turbine tower and the lightning channel is established, so that the complex structure is solved in a simplified manner.
3. The inductive lightning overvoltage calculation method provided by the invention adopts the Agrawal field line coupling model and the FDTD method which consider non-ideal ground, so that the calculation process is simplified, the modeling accuracy is higher, and the inductive lightning overvoltage calculation method is suitable for being applied to actual engineering.
Drawings
Fig. 1 is a flow chart of the present invention.
FIG. 2 is a diagram of a field wire model of a lightning strike blower generating induced overvoltage in a wind farm collector.
Detailed Description
The present invention will be described in detail with reference to the accompanying drawings and examples.
Fig. 1 is a flowchart of a method for estimating lightning induction overvoltage of a wind power plant collector line in a high altitude mountain area according to the present invention, fig. 2 is a field line model diagram of a lightning stroke fan for generating induction overvoltage in the wind power plant collector line, and as can be seen from fig. 1 and 2, the method for estimating lightning induction overvoltage comprises the following steps:
and 1, setting current collecting circuit information of the wind power plant.
Sampling wind power plant collecting line information required to be subjected to induction overvoltage calculation to obtain the following wind power plant collecting line information: lightning current peak value I, lightning back striking channel height H, fan tower vertical height H, current collecting line wire pair average vertical height H a 。
And 2, calculating the back-striking current i (z', t) of the lightning stroke fan.
In calculating the back-striking current of a lightning stroke fan, the following basic assumption is made:
1) The lightning striking back channel is perpendicular to the ground and is formed by connecting infinite current elements in vertical orientation;
2) The back-striking current of the lightning stroke fan propagates upwards along the lightning back-striking channel at a speed v;
in the lightning strike back channel, any vertical height is taken and recorded as vertical height z ', and the strike back current i (z ', t) at the vertical height z ' is calculated, wherein t is time.
When z '. Gtoreq.h, the strike back current i (z ', t) at the vertical height z ' is expressed as follows:
when 0.ltoreq.z ' < h, the strike back current i (z ', t) at the vertical height z ' is expressed as follows:
wherein:
t is the development time of lightning current, m is the current gradient factor, lambda is the current attenuation constant, q is the reflection times of lightning current at two ends of a high tower, c is the speed of light, v is the propagation speed of back-striking current, and ρ top As the top current reflection coefficient ρ bot Is the bottom current reflection coefficient.
u is the sea-going function, whenWhen u=1; when->When u=0;
η is the peak value correction coefficient and,τ 1 is the wave head time constant, τ 2 Is the wave tail time constant;
and 3, establishing a lightning back-striking electromagnetic field calculation model considering the earth loss.
Step 3.1, calculating a spatial electromagnetic field generated by the back-striking current by using maxwell's equations under the condition that the ideal conductor is earth, comprising: axial magnetic fieldHorizontal electric field E r (r, z, t) and vertical electric field E z (r, z, t) whose maxwell equations are expressed as follows:
/>
wherein: r is the radial coordinate of the space electromagnetic field, z is the vertical height of any observed point in the space electromagnetic field and is recorded as the height z epsilon 0 Is vacuum dielectric constant; r is the linear distance of the current dipole to the point where the space is observed,R 1 for the linear distance of the mirror current to the point of the space to be observed, +.> For a vertical height z', time +.>A back-striking current value for the alignment; />For a vertical height z', time +.>The value of the return current at the moment;for a vertical height z', time +.>Differentiation of the time-of-day kick-back current with respect to time;for a vertical height z', time +.>Time-of-day kick-back current differentiation with respect to time.
Step 3.2, establishing a horizontal electric field E taking into account the ground loss rg The frequency domain calculation correction equation for (r, z, jω) is as follows:
wherein: e (E) r (r, z, jω) is a Fourier transform of the horizontal component of the electric field at a height z,sigma, a form of fourier transformation of the azimuthal component of the magnetic field at the surface g For earth conductivity, epsilon rg Mu, relative dielectric constant to earth 0 Is the earth magnetic conductivity, ω is the frequency, and j is the imaginary part.
And 4, establishing a coupling calculation model of the electromagnetic field excited by the lightning back-striking electromagnetic field and the transmission line.
Step 4.1, when the earth and line loss are considered, a transmission line Agrawal model under electromagnetic excitation of lightning return stroke is established, and the expression is as follows:
wherein: u (u) s (x, t) is the lightning induced voltage scattering voltage component of the wind power plant collector line conductor, s is the sign of the induced voltage scattering voltage component, x is the argument, i (x, t) is the lightning induced current of the wind power plant collector line conductor, [ L ]]Inductance matrix for unit length of transmission line, [ C ]]For a matrix of capacitances per unit length of transmission line, E r (x，H a T) is the lightning back-striking electric field strength in the direction of the conductor at the height of the conductor of the wind power plant current collecting circuit, and ζ g (t- τ) is the transient ground impedance matrix, τ is an intermediate variable of time.
Wherein mu 0 Is the vacuum magnetic permeability coefficient; epsilon 0 Is vacuum dielectric constant; epsilon rg Is the relative dielectric constant; erfc is the function of the error,
step 4.2, solving an induced voltage vector u (x, t) on the current collecting line conductor, wherein the expression is as follows:
and 5, carrying out Agrawal model numerical solution on the current collecting line wires by adopting a time domain finite difference method to obtain the induced overvoltage value of the current collecting line of the wind power plant.
Firstly, calculating the induction scattering voltage of the head end of a transmission lineInduced scattering voltage with transmission line endThe expression is as follows:
wherein: g is a matching resistor, Δx is a space step, Δt is a time step, n is an integer representing a time step, n=0, 1,2 … NDT, NDT is a maximum time step integer, k is an integer representing a space step, k=0, 1,2 … NDX, NDX is a maximum space step integer;is the scattering voltage at the time of n delta t at the head end of the transmission line; />Is the scattering voltage at the end of the transmission line at the time nΔt; />For being positioned +.>Department(s),>the induced current at the moment; />To be positioned atDepartment(s),>the induced current at the moment; />Is the vertical electric field at the moment nDeltat at the vertical height z at the head end of the transmission line, +.>A vertical electric field at a vertical height z, at the end of the transmission line, at time nΔt; />Is a vertical electric field at the (n+1) deltat moment at the vertical height z at the head end of the transmission line; />At the end of the transmission line, at a vertical electric field with vertical height z, (n+1) at time Δt.
Next, the portions other than the head end and the tail end of the collector line are referred to as a middle portion, any one of the middle portions is denoted as k, k=1, 2 … NDX-1, and the induced scattering voltage at k is obtainedThe expression is as follows:
wherein:for being positioned +.>Department(s),>time-of-day induced current, ">For being positioned +.>Department(s),>time-of-day induced current, ">Is the induced voltage at kΔx, at nΔt.
Finally, the induced current is calculatedThe expression is as follows:
wherein: zeta type toy g In the form of a transient earth impedance matrix,for being positioned +.>Department(s),> time horizontal electric field, ">For being positioned +.>Department(s),>the horizontal electric field at the moment in time,for being positioned +.>Department(s),>time-of-day induced current, ">For being positioned +.>Department(s),>the induced current at the moment.
According to the technical scheme, the method comprises the steps of firstly establishing a plurality of top and bottom back-striking current attenuation models of the lightning stroke fan, calculating a lightning back-striking electromagnetic field, calculating transient response of a wind power plant collecting line under excitation of the lightning back-striking electromagnetic field, developing research on a collecting line lightning induction overvoltage calculation method through establishing a field line coupling model, carrying out numerical solution along with the field line calculation model by adopting a time domain finite difference method, and providing a collecting line lightning induction overvoltage calculation method considering ground loss, so that a calculation result is combined with reality more accurately.
Claims (1)
1. The method for estimating the lightning induction overvoltage of the wind power plant collector line in the high-altitude mountain area is characterized by comprising the following steps of:
step 1, setting current collecting circuit information of a wind power plant;
sampling wind power plant collecting line information required to be subjected to induction overvoltage calculation to obtain the following wind power plant collecting line information: lightning current peak value I, lightning back striking channel height H, fan tower vertical height H, current collecting line wire pair average vertical height H a ；
Step 2, calculating the back-striking current i (z', t) of the lightning stroke fan;
in calculating the back-striking current of a lightning stroke fan, the following basic assumption is made:
1) The lightning striking back channel is perpendicular to the ground and is formed by connecting infinite current elements in vertical orientation;
2) The back-striking current of the lightning stroke fan propagates upwards along the lightning back-striking channel at a speed v;
in the lightning strike back channel, any vertical height is taken and recorded as vertical height z ', strike back current i (z ', t) at the vertical height z ' is calculated, wherein t is time;
when z '. Gtoreq.h, the strike back current i (z ', t) at the vertical height z ' is expressed as follows:
when 0.ltoreq.z ' < h, the strike back current i (z ', t) at the vertical height z ' is expressed as follows:
wherein:
t is the development time of lightning current, m is the current gradient factor, lambda is the current attenuation constant, q is the reflection times of lightning current at two ends of a high tower, c is the speed of light, v is the propagation speed of back-striking current, and ρ top As the top current reflection coefficient ρ bot Is the bottom current reflection coefficient;
u is the sea-going function, whenWhen u=1; when->When u=0;
η is the peak value correction coefficient and,τ 1 is the wave head time constant, τ 2 Is the wave tail time constant;
step 3, establishing a lightning back-striking electromagnetic field calculation model considering the earth loss;
step 3.1, calculating a spatial electromagnetic field generated by the back-striking current by using maxwell's equations under the condition that the ideal conductor is earth, comprising: axial magnetic fieldHorizontal electric field E r (r, z, t) and vertical electric field E z (r, z, t) whose maxwell equations are expressed as follows:
wherein: r is the radial coordinate of the space electromagnetic field, z is the vertical height of any observed point in the space electromagnetic field and is recorded as the height z epsilon 0 Is vacuum dielectric constant; r is the linear distance of the current dipole to the point where the space is observed,R 1 for the linear distance of the mirror current to the point of the space to be observed, +.> For a vertical height z', time +.>The value of the return current at the moment;for a vertical height z', time +.>The value of the return current at the moment; />For a vertical height z', time +.>Differentiation of the time-of-day kick-back current with respect to time; />For a vertical height z', time +.>Differentiation of the time-of-day kick-back current with respect to time;
step 3.2, establishing a horizontal electric field E taking into account the ground loss rg The frequency domain calculation correction equation for (r, z, jω) is as follows:
wherein: e (E) r (r, z, jω) is a Fourier transform of the horizontal component of the electric field at a height z,sigma, a form of fourier transformation of the azimuthal component of the magnetic field at the surface g For earth conductivity, epsilon rg Mu, relative dielectric constant to earth 0 The geomagnetic conductivity is the geomagnetic conductivity, ω is the frequency, and j is the imaginary part;
step 4, establishing a coupling calculation model of the electromagnetic field excited by the lightning back-striking electromagnetic field and the transmission line;
step 4.1, when the earth and line loss are considered, a transmission line AgraWal model under electromagnetic excitation of lightning return stroke is established, and the expression is as follows:
wherein: u (u) s (x, t) is the lightning induced voltage scattering voltage component of the wind power plant collector line conductor, s is the sign of the induced voltage scattering voltage component, x is the argument, i (x, t) is the lightning induced current of the wind power plant collector line conductor, [ L ]]Inductance matrix for unit length of transmission line, [ C ]]For a matrix of capacitances per unit length of transmission line, E r (x，H a T) is the lightning back-striking electric field strength in the direction of the conductor at the height of the conductor of the wind power plant current collecting circuit, and ζ g (t- τ) is a transient earth impedance matrix, τ is an intermediate variable of time;
wherein mu 0 Is vacuumMagnetic permeability coefficient; epsilon 0 Is vacuum dielectric constant; epsilon rg Is the relative dielectric constant; erfc is the function of the error,
step 4.2, solving an induced voltage vector u (x, t) on the current collecting line conductor, wherein the expression is as follows:
step 5, carrying out Agrawal model numerical solution of the current collecting line wires by adopting a time domain finite difference method to obtain induced overvoltage values of the current collecting lines of the wind power plant;
firstly, calculating the induction scattering voltage of the head end of a transmission lineInduce scattering voltage with transmission line end>The expression is as follows:
wherein: g is a matching resistor, Δx is a space step, Δt is a time step, n is an integer representing a time step, n=0, 1,2 … NDT, NDT is a maximum time step integer, k is an integer representing a space step, k=0, 1,2 … NDX, NDX is a maximum space step integer;is arranged at the head end of the transmission line,A scattering voltage at time nΔt; />Is the scattering voltage at the end of the transmission line at the time nΔt; />For being positioned +.>Department(s),>the induced current at the moment; />To be positioned atDepartment(s),>the induced current at the moment; />Is the vertical electric field at the moment nDeltat at the vertical height z at the head end of the transmission line, +.>A vertical electric field at a vertical height z, at the end of the transmission line, at time nΔt; />Is a vertical electric field at the (n+1) deltat moment at the vertical height z at the head end of the transmission line; />A vertical electric field at a vertical height z, (n+1) Δt at the end of the transmission line;
next, the portions other than the head end and the tail end of the collector line are referred to as a middle portion, any one of the middle portions is denoted as k, k=1, 2 … NDX-1, and the induced scattering voltage at k is obtainedThe expression is as follows:
wherein:for being positioned +.>Department(s),>time-of-day induced current, ">To be positioned atDepartment(s),>time-of-day induced current, ">Is the induced voltage at kΔx, at nΔt;
finally, the induced current is calculatedThe expression is as follows:
wherein: zeta type toy g In the form of a transient earth impedance matrix,for being positioned +.>Department(s),> time horizontal electric field, ">For being positioned +.>Department(s),>time horizontal electric field, ">For being positioned +.>Department(s),>time-of-day induced current, ">For being positioned +.>A part(s),The induced current at the moment.
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| KR20140029865A (en) * | 2012-08-30 | 2014-03-11 | 한국전력공사 | Apparatus and method of evaluating performance for lightning protection in distribution lines |
| CN104850738A (en) * | 2015-04-29 | 2015-08-19 | 重庆大学 | Method for calculating lightning induction voltage of overhead power line tower |
| CN109711088A (en) * | 2019-01-15 | 2019-05-03 | 国网湖北省电力有限公司电力科学研究院 | A kind of distribution line lightning induced voltage calculation method of Electromagnetic field |
| CN110441655A (en) * | 2019-08-08 | 2019-11-12 | 中广核玉溪元江风力发电有限公司 | A kind of wind power plant collection electric line lightning stroke ground fault detection system |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| KR20140029865A (en) * | 2012-08-30 | 2014-03-11 | 한국전력공사 | Apparatus and method of evaluating performance for lightning protection in distribution lines |
| CN104850738A (en) * | 2015-04-29 | 2015-08-19 | 重庆大学 | Method for calculating lightning induction voltage of overhead power line tower |
| CN109711088A (en) * | 2019-01-15 | 2019-05-03 | 国网湖北省电力有限公司电力科学研究院 | A kind of distribution line lightning induced voltage calculation method of Electromagnetic field |
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