CN116338379A - Method and system for rapidly calculating power grid fault voltage distribution under new energy access - Google Patents
Method and system for rapidly calculating power grid fault voltage distribution under new energy access Download PDFInfo
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Abstract
The invention discloses a method and a system for rapidly calculating power grid fault voltage distribution under new energy access, wherein the method comprises the following steps: establishing a new energy controlled voltage source model and determining a network node admittance matrix Y; after the power grid fails, calculating fault current injected by each node; when the node is an active node and the connected power supply is a new energy unit, ignoring the phase change of the voltage of the grid-connected point end of the new energy before and after the fault, and calculating the fault current of the power supply injected into the node; correcting the node admittance matrix Y based on the position of the fault point; and calculating to obtain the fault voltage of each node by using the corrected admittance matrix of each node and the fault current injected by each node. When the injection fault current of the active node of the new energy unit is calculated by using the power supply connected with the power supply, the phase of the equivalent electromotive force of the new energy is determined by using the terminal voltage phase before the fault, so that nonlinear iterative calculation is avoided, the calculation complexity is reduced, and the calculation speed is improved.
Description
Technical Field
The invention relates to the technical field of power grid fault voltage distribution calculation, in particular to a method and a system for rapidly calculating power grid fault voltage distribution under new energy access.
Background
The statements in this section merely provide background information related to the present disclosure and may not necessarily constitute prior art.
The power grid fault voltage distribution calculation refers to calculation of voltage drop conditions of all nodes of a power grid after faults, on one hand, fault currents of all branches can be calculated by obtaining the voltages of all nodes after the faults, and therefore basis is provided for design of power grid relay protection; on the other hand, by observing the node voltage distribution after faults at different positions in the network, the reactive power demand of each node in the network can be clarified, and the reactive power optimization configuration of the power grid is guided. Therefore, the power grid fault voltage distribution calculation has important significance for safe and stable operation of the power grid.
The duty ratio of the new energy in the power system is continuously improved, and the external characteristics of the new energy after the new energy fails are greatly different from those of the synchronous machine: synchronous machine control does not respond well after a fault, so that the synchronous machine control shows stable external voltage source characteristics; the new energy fault ride-through control has the capability of quick response, the external fault characteristic is determined by a fault ride-through control strategy, and the voltage source characteristic of the synchronous machine cannot be displayed. Therefore, the access of new energy brings great challenges to the analysis of the power grid faults, and the calculation of fault voltage distribution of each node of the power grid is complicated.
At present, for a traditional power system only comprising synchronous machines, firstly, a complex sequence network after faults is formed according to a symmetrical component method, a node admittance matrix is established, then boundary conditions are determined according to fault positions and types, and finally, a linear equation set U=Y is solved -1 I, obtaining fault voltage distribution. After the new energy is accessed, the external fault characteristics of the system are different from those of the synchronous machine, so that the system cannot be modeled as an independent voltage source, and the system of equations is generally calculated by adopting a non-linear equation set solving method such as a Newton-Laporton method due to the non-linearity brought by the new energy access, so that the calculation process is relatively complex.
Disclosure of Invention
In order to solve the problems, the invention provides a method and a system for rapidly calculating the power grid fault voltage distribution under the condition of new energy access, and external characteristic equivalent modeling is carried out on new energy according to a typical new energy fault ride-through control strategy; meanwhile, nonlinear equation set calculation caused by new energy access is avoided, and rapid calculation of power grid fault voltage distribution under a certain precision requirement is realized.
In some embodiments, the following technical scheme is adopted:
a rapid calculation method for power grid fault voltage distribution under new energy access comprises the following steps:
a new energy controlled voltage source model is established by considering a new energy fault ride-through control strategy;
determining a network node admittance matrix Y based on a network topology structure of a new energy access power grid;
after the power grid fails, calculating fault current injected by each node; when the node is an active node and the connected power supply is a new energy unit, based on the new energy controlled voltage source model, the phase change of the voltage of the new energy grid-connected point before and after the fault is ignored, and the fault current of the power supply injected into the node is calculated;
correcting the node admittance matrix Y based on the position of the fault point;
and calculating to obtain the fault voltage of each node by using the corrected admittance matrix of each node and the fault current injected by each node.
In other embodiments, the following technical solutions are adopted:
a power grid fault voltage distribution rapid computing system under new energy access comprises:
the model building module is configured to consider a new energy fault ride-through control strategy and build a new energy controlled voltage source model;
the admittance matrix establishment module is configured to determine a network node admittance matrix Y based on a network topology structure of the new energy access power grid;
the fault current calculation module is configured to calculate fault current injected by each node after the power grid fails; when the node is an active node and the connected power supply is a new energy unit, based on the new energy voltage source model, the phase change of the voltage of the new energy grid-connected point before and after the fault is ignored, and the fault current of the power supply injected into the node is calculated;
the admittance matrix correction module is configured to correct the node admittance matrix Y based on the position of the fault point;
the fault voltage calculation module is configured to calculate the fault voltage of each node by using the corrected admittance matrix of each node and the fault current injected by each node.
In other embodiments, the following technical solutions are adopted:
a terminal device comprising a processor and a memory, the processor for implementing instructions; the memory is used for storing a plurality of instructions which are suitable for being loaded by the processor and executing the rapid calculation method for the power grid fault voltage distribution under the access of the new energy.
In other embodiments, the following technical solutions are adopted:
a computer readable storage medium having stored therein a plurality of instructions adapted to be loaded by a processor of a terminal device and to perform the above-described method for fast calculation of grid fault voltage distribution under new energy access.
Compared with the prior art, the invention has the beneficial effects that:
(1) According to a typical new energy fault ride-through control strategy, the external characteristic equivalent modeling is carried out on the new energy; the active and reactive current characteristics of the new energy are analogized with the voltage source model of the synchronous machine, so that the construction of the new energy equivalent model is facilitated.
(2) When the injection fault current of the active node of the new energy unit connected with the power supply is calculated, the phase change of the end voltage of the new energy grid-connected point before and after the fault is ignored, and the phase of the equivalent electromotive force of the new energy is determined by the end voltage phase before the fault, so that nonlinear iterative calculation is avoided, the calculation complexity is reduced, and the calculation speed is improved.
Additional features and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.
Drawings
FIGS. 1 (a) - (b) are diagrams of voltage source models and phasors for synchronous machines in accordance with embodiments of the present invention;
FIG. 2 is a new energy controlled voltage source model in an embodiment of the invention;
FIG. 3 is a schematic diagram of a three-machine nine-node network in an embodiment of the present invention;
FIGS. 4 (a) - (b) are node voltages at the time of the No. 6 node failure in the transient failure phase and the transient failure phase according to the embodiments of the present invention;
FIGS. 5 (a) - (b) are node voltages at the time of the No. 7 node failure in the transient failure phase and the transient failure phase according to the embodiments of the present invention;
FIGS. 6 (a) - (b) are node voltages for the 4-6 branch fault time sub-transient fault phase and transient fault phase in an embodiment of the present invention;
fig. 7 is a schematic diagram of a method for rapidly calculating power grid fault voltage distribution under new energy access in an embodiment of the invention.
Detailed Description
It should be noted that the following detailed description is illustrative and is intended to provide further explanation of the invention. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.
It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of exemplary embodiments according to the present invention. As used herein, the singular is also intended to include the plural unless the context clearly indicates otherwise, and furthermore, it is to be understood that the terms "comprises" and/or "comprising" when used in this specification are taken to specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof.
Example 1
In one or more embodiments, a method for rapidly calculating power grid fault voltage distribution under new energy access is disclosed, and in combination with fig. 7, the method specifically includes the following steps:
(1) A new energy controlled voltage source model is established by considering a new energy fault ride-through control strategy;
in this embodiment, in order to prevent impact caused by off-grid of new energy after a power grid fault occurs, it is generally required that the new energy has a certain fault-crossing capability, and it is ensured that the new energy keeps running without off-grid during the fault period through a fault-crossing control strategy. At present, a typical new energy fault ride-through control strategy is reactive current control, namely, the new energy unit is required to quickly respond when the voltage of a grid-connected point drops, a certain recovery of the voltage of a reactive current supporting end is sent, and the magnitude of reactive current needs to be satisfied:
I q ≥K Q (0.9-U m )×I n (1)
wherein U is m For the voltage amplitude of new energy grid-connected point line, I n Rated current K of new energy unit Q For reactive current coefficient, 1.5, I is generally taken q Is reactive current of the new energy unit.
For active current, the value before the fault is generally kept unchanged, but since the new energy source before the fault generally operates in a unit power factor mode, namely the reactive current is 0, the reactive current increased after the fault tends to occupy a part of current capacity, and therefore, considering the current capacity limitation, the active current after the fault can be expressed as:
wherein I is p0 As the value of the active current before failure, I pmax For the maximum active current capacity, I, remaining at the present reactive current p The active current of the new energy unit after the fault.
In order to build a new energy external characteristic equivalent model which is convenient to calculate, the active and reactive current characteristics of the new energy external characteristic equivalent model can be analogized with a voltage source model of a synchronous machine, and the voltage source model of the synchronous machine and phasor diagrams thereof are shown in fig. 1 (a) - (b).
Wherein E is the electromotive force of a synchronous machine, X s Is the reactance of the stator of the synchronous machine. The sub-transient electromotive force E 'and the transient electromotive force E', X are respectively taken in different fault phases E s Also taken as secondary transient reactance X "and transient reactance X', respectively, is available from the phasor diagram of fig. 1 (b):
the active and reactive current output of the synchronous machine voltage source model can be obtained by arrangement:
wherein U is synchronous machine grid-connected point terminal voltage, delta is synchronous machine power angle and X s Is a synchronous machine reactance.
For the convenience of calculation, the new energy under reactive current control can be modeled as a voltage source model similar to a synchronous machine, and the per-unit new energy output current characteristics after failure are substituted into formula (4), namely:
according to the corresponding equality principle, it is possible to:
simplifying the equivalent electromotive force E, the power angle delta and the reactance parameter X of the new energy voltage source model eq The calculation formulas of (a) are respectively as follows:
wherein delta is the equivalent power angle of the new energy controlled voltage source model, I p0 K is the active current output of the new energy unit before failure Q The reactive current coefficient in the new energy fault ride-through strategy is E is the equivalent electromotive force of the new energy controlled voltage source model, X eq And the equivalent reactance of the new energy controlled voltage source model is obtained.
It can be seen that the establishment of the voltage source model can be completed only by defining the fault ride-through control strategy of the new energy and the active output condition before the fault. It should be noted that the new energy is generally a grid-like type and cannot be modeled as an independent voltage source identical to the synchronous machine, and the phase of the equivalent electromotive force in the voltage source model needs to be determined by relying on the grid-connected voltage phase, so that the new energy equivalent external characteristic model after the fault established by the method is actually a phase-controlled voltage source model as shown in fig. 2.
(2) Determining a network node admittance matrix Y based on a network topology structure of a new energy access power grid;
specifically, for a power grid with n nodes and m branches, including a synchronous machines and b new energy sources, to obtain the fault voltage distribution of a node or branch after fault, firstly, the network topology structure needs to be defined, and the admittance matrix Y of the network nodes is established, and diagonal elements Y in the matrix ii The self admittance is equal to the unit voltage added to the i node in value, and when all other nodes are grounded, the current of the network is injected from the i node; off-diagonal element Y in matrix ij For transadmittance, which is equal in value to i node plus unit voltage, the current of the network is injected from j node when the remaining nodes are all grounded. Y is Y ii And Y is equal to ij The calculation method of (1) is as follows:
wherein j is another node connected with the node i; y is ij As admittance value of branch i-j, if node i and node j have no direct connection relationship, y ij ＝0；y i0 For node i to ground admittance values, in this embodiment, the load uses a constant impedance model, accounting for the ground admittance y of the connected node pair i0 Participate in the calculation.
(3) After the power grid fails, calculating fault current injected by each node;
according to u=y -1 I, the voltage distribution after the fault is required, and the fault current injected by each node is required to be clarified. Specifically:
(1) for passive nodes, the sum of injection current vectors is 0, namely the corresponding position element of column vector I is 0, and for active nodes, the fault current sent by the active nodes needs to be calculated according to an equivalent model of the power supply after the fault.
(2) For active nodesIf the power source connected with the active node is a synchronous machine, the active node can be modeled as a constant voltage source, and due to the wide application of the quick relay protection device, a fault element can be quickly cut off from a power grid after short circuit, so that the power frequency component of short circuit current in a short time after short circuit can be approximately considered to be equal to the initial value of the short circuit current, and the equivalent electromotive force after the fault can be calculated according to the terminal voltage before the fault
And end current->
Calculated, namely:
wherein, the liquid crystal display device comprises a liquid crystal display device,
is the sub-transient electromotive force of the synchronous machine, X' is the sub-transient reactance, and +.>
Can be directly calculated according to the data before the fault.
After the fault is continued for a period of time, the sub-transient state electric quantity is basically attenuated, and the parameters of the voltage source model of the synchronous machine are modified into transient state parameters for calculation at the moment, and the transient state electromotive force is calculated
The calculation method is similar to the sub-transient electromotive force:
wherein X' is the transient reactance of the synchronous machine. Transient electromotive force
Or can be directly calculated according to the data before the fault.
(3) If the power source connected with the active node is a new energy unit, a controlled voltage source model is built according to the new energy controlled voltage source model building method, the equivalent electromotive force phase of the model needs to be determined according to the end voltage phase of the new energy grid-connected point after the fault, nonlinear calculation is introduced, so that the phase change of the end voltage of the new energy grid-connected point before and after the fault is ignored in the method for improving the calculation speed, the phase of the equivalent electromotive force of the new energy can be determined by the end voltage phase before the fault, nonlinear iterative calculation is avoided, and under the premise, the electromotive force phasor of the new energy equivalent controlled voltage source model is:
in θ u0 The voltage phase of the grid-connected point end of the new energy before the fault is represented by delta, and the equivalent power angle of the controlled voltage source model is represented by delta.
After the power supply electromotive force of each active node is determined, the fault current of the power supply injected into the node can be calculated according to the following formula:
wherein X is equivalent reactance in the power supply, subsransient reactance or transient reactance for the synchronous machine, and X in formula (7) for new energy eq 。
Is the electromotive force phasor of the power supply>
And (5) voltage phasors for grid-connected ports of the power supply.
Substituting equation (12) into equation set i=yu and multiplying the voltage column vector into the node admittance matrix yields, for any active node I:
at this time, the i node voltage after the fault still exists on the left side of the equation
This unknown can be shifted to the right of the equation, and then the above equation becomes:
it can be seen that after the self-admittance term of the active node in the node admittance matrix is modified by adding the internal equivalent admittance of the power supply, each element in the left current column vector can be calculated according to the data before the fault.
(4) Correcting the node admittance matrix Y based on the position of the fault point;
the influence of faults on the whole network can be reflected by modifying the node admittance matrix, and two correction methods exist according to different fault positions:
(1) if a fault occurs at the node i, the grounding transition resistance is recorded as R f Then is equivalent to adding an impedance of R at the node i f And thus the node admittance matrix node i is self-admittance Y ii Adding to
And (3) correcting.
(2) If the fault occurs in the branch i-j and the distance from the fault point to the node i is k, the transition resistance to ground is R f In this case, the fault point can be regarded as a newly added n+1th node, the node admittance matrix also needs to be increased by one dimension, at this time, the nodes i and j have no direct connection relation, but are respectively connected with the node n+1, and then the related elements of the node admittance matrix need to be modified as follows:
(5) By calculating a linear equation set u=y using the corrected admittance matrix of each node and the fault current injected from each node -1 And I, obtaining the fault voltage distribution of each node of the whole network.
In the embodiment, a three-machine nine-node model shown in fig. 3 is built in DIgSILENT Powerfactory to simulate and verify the proposed calculation method, and parameters of each unit and voltage data of each node in steady-state operation are shown in tables 1 and 2.
Table 1 set parameters
TABLE 2 Voltage data at nodes
| Node numbering | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 |
| Voltage/p.u. | 1.034 | 1.025 | 1.036 | 1.019 | 0.991 | 1.004 | 1.026 | 1.018 | 1.037 |
Faults with different positions and different degrees are respectively set, simulation results are compared with fault voltage distribution calculated by the proposed rapid calculation method, and the results are as follows:
(1) FIGS. 4 (a) - (b) show node number 6 (Bus 6) failure, transition resistance R f When the voltage is=60 omega, the node voltage simulation results of the sub-transient fault phase and the transient fault phase are obtained;
the voltage values at each node are shown in table 3 below:
TABLE 3 voltage values at nodes
The maximum error of the simulated voltage and the fast calculated voltage is 4.5%.
(2) FIGS. 5 (a) - (b) show node 7 (Bus 7) failure, transition resistance R f When the voltage is=80Ω, the node voltage simulation results of the sub-transient fault phase and the transient fault phase are obtained;
the voltage values at each node are shown in table 4 below:
TABLE 4 voltage values at nodes
The maximum error of the simulated voltage and the fast calculated voltage is 4.9%.
(3) FIGS. 6 (a) - (b) show that branch 4-6 (Line 4-Line 6) fails 50% from node 4, transition resistance R f When the voltage is=60 omega, the node voltage simulation results of the sub-transient fault phase and the transient fault phase are obtained;
the voltage values at each node are shown in table 5 below:
TABLE 5 voltage values at nodes
The maximum error of the simulated voltage and the fast calculated voltage is 4.1%.
According to the comparison result, the fault voltage distribution calculated by the rapid calculation method for the fault voltage distribution of the power grid under the access of the new energy provided by the embodiment has the maximum error within 5% compared with the simulation result, the calculation accuracy meets the engineering requirement, and the rapid calculation method has the advantage of high calculation speed, and the fault analysis calculation of the power grid under the access of the new energy is simplified to a certain extent.
Example two
In one or more embodiments, a system for rapidly calculating power grid fault voltage distribution under new energy access is disclosed, comprising:
the model building module is configured to consider a new energy fault ride-through control strategy and build a new energy controlled voltage source model;
the admittance matrix establishment module is configured to determine a network node admittance matrix Y based on a network topology structure of the new energy access power grid;
the fault current calculation module is configured to calculate fault current injected by each node after the power grid fails; when the node is an active node and the connected power supply is a new energy unit, based on the new energy controlled voltage source model, the phase change of the voltage of the new energy grid-connected point before and after the fault is ignored, and the fault current of the power supply injected into the node is calculated;
the admittance matrix correction module is configured to correct the node admittance matrix Y based on the position of the fault point;
the fault voltage calculation module is configured to calculate the fault voltage of each node by using the corrected admittance matrix of each node and the fault current injected by each node.
It should be noted that, the specific implementation manner of each module has been described in the first embodiment, and will not be described in detail herein.
Example III
In one or more embodiments, a terminal device is disclosed, including a server, where the server includes a memory, a processor, and a computer program stored on the memory and capable of running on the processor, where the processor implements the method for quickly calculating a grid fault voltage distribution under new energy access in embodiment one when the processor executes the program. For brevity, the description is omitted here.
It should be understood that in this embodiment, the processor may be a central processing unit CPU, and the processor may also be other general purpose processors, digital signal processors DSP, application specific integrated circuits ASIC, off-the-shelf programmable gate array FPGA or other programmable logic device, discrete gate or transistor logic devices, discrete hardware components, or the like. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like.
The memory may include read only memory and random access memory and provide instructions and data to the processor, and a portion of the memory may also include non-volatile random access memory. For example, the memory may also store information of the device type.
In implementation, the steps of the above method may be performed by integrated logic circuits of hardware in a processor or by instructions in the form of software.
Example IV
In one or more embodiments, a computer-readable storage medium is disclosed, in which a plurality of instructions are stored, the instructions being adapted to be loaded by a processor of a terminal device and to perform the method for fast calculation of a grid fault voltage distribution under new energy access as described in embodiment one.
While the foregoing description of the embodiments of the present invention has been presented in conjunction with the drawings, it should be understood that it is not intended to limit the scope of the invention, but rather, it is intended to cover all modifications or variations within the scope of the invention as defined by the claims of the present invention.
Claims (10)
1. The utility model provides a method for rapidly calculating power grid fault voltage distribution under new energy access, which is characterized by comprising the following steps:
a new energy controlled voltage source model is established by considering a new energy fault ride-through control strategy;
determining a network node admittance matrix Y based on a network topology structure of a new energy access power grid;
after the power grid fails, calculating fault current injected by each node; when the node is an active node and the connected power supply is a new energy unit, based on the new energy controlled voltage source model, the phase change of the voltage of the new energy grid-connected point before and after the fault is ignored, and the fault current of the power supply injected into the node is calculated;
correcting the node admittance matrix Y based on the position of the fault point;
and calculating to obtain the fault voltage of each node by using the corrected admittance matrix of each node and the fault current injected by each node.
2. The rapid calculation method for power grid fault voltage distribution under new energy access as claimed in claim 1, wherein equivalent electromotive force, power angle and reactance parameters of the new energy controlled voltage source model are respectively:
wherein delta is the equivalent power angle of the new energy controlled voltage source model, I p0 K is the active current output of the new energy unit before failure Q The reactive current coefficient in the new energy fault ride-through strategy is E is the equivalent electromotive force of the new energy controlled voltage source model, X eq And the equivalent reactance of the new energy controlled voltage source model is obtained.
3. The rapid calculation method for power grid fault voltage distribution under new energy access as claimed in claim 1, wherein diagonal element Y in network node admittance matrix Y ii The self admittance is equal to the unit voltage applied to the i node in value, and when all other nodes are grounded, the current of the network is injected from the i node;
off-diagonal element Y in network node admittance matrix Y ij The transadmittance, which is equal in value to the unit voltage applied to the i node, injects current into the network from the j node when all the remaining nodes are grounded.
4. The method for rapidly calculating the distribution of the fault voltage of the power grid under the access of the new energy according to claim 1, wherein when the node is a passive node, the sum of vectors of the node injection currents is 0, namely, the fault current injected by the node is 0.
5. The method for rapidly calculating the distribution of the fault voltage of the power grid under the access of the new energy according to claim 1, wherein when the node is an active node and the power source connected with the node is a synchronous machine, the equivalent electromotive force after the fault is calculated according to the terminal voltage and the terminal current before the fault, and further the fault current injected by each node is calculated according to the internal voltage of the power source, the equivalent electromotive force after the fault and the equivalent reactance in the power source.
6. The method for rapidly calculating the distribution of the fault voltage of the power grid under the access of the new energy according to claim 1, wherein when the node is an active node and the power source connected with the node is a new energy unit, the phase change of the end voltage of the grid-connected point of the new energy before and after the fault is ignored, the end voltage phase before the fault is used as the phase of the equivalent electromotive force of the new energy after the fault, the electromotive force of the new energy controlled voltage source model is calculated, and then the fault current injected by each node is calculated according to the internal voltage of the power source, the equivalent electromotive force after the fault and the equivalent reactance in the power source.
7. The rapid calculation method for power grid fault voltage distribution under new energy access as claimed in claim 1, wherein the node admittance matrix Y is modified based on the location of the fault point, specifically:
if a fault occurs at the node i, the grounding transition resistance is recorded as R f The self admittance Y of the node admittance matrix I number node is calculated ii Adding to
Correcting;
if the fault occurs on the branch i-j and the distance from the fault point to the node i is k, the grounding transition resistance is R f And regarding the fault point as a newly added n+1st node, and correspondingly adding one dimension to the node admittance matrix.
8. The utility model provides a new energy inserts quick computing system of electric wire netting fault voltage distribution which characterized in that includes:
the model building module is configured to consider a new energy fault ride-through control strategy and build a new energy voltage source model;
the admittance matrix establishment module is configured to determine a network node admittance matrix Y based on a network topology structure of the new energy access power grid;
the fault current calculation module is configured to calculate fault current injected by each node after the power grid fails; when the node is an active node and the connected power supply is a new energy unit, based on the new energy controlled voltage source model, the phase change of the voltage of the new energy grid-connected point before and after the fault is ignored, and the fault current of the power supply injected into the node is calculated;
the admittance matrix correction module is configured to correct the node admittance matrix Y based on the position of the fault point;
the fault voltage calculation module is configured to calculate the fault voltage of each node by using the corrected admittance matrix of each node and the fault current injected by each node.
9. A terminal device comprising a processor and a memory, the processor for implementing instructions; the memory is used for storing a plurality of instructions, wherein the instructions are suitable for being loaded by a processor and executing the method for quickly calculating the power grid fault voltage distribution under the new energy access according to any one of claims 1 to 7.
10. A computer readable storage medium, in which a plurality of instructions are stored, characterized in that the instructions are adapted to be loaded by a processor of a terminal device and to perform the method for fast calculation of a grid fault voltage distribution under new energy access according to any one of claims 1-7.
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