CN112966463A - Efficient simulation method for distributed grid-connected system of converter group - Google Patents
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Abstract
The invention discloses a high-efficiency simulation method of a distributed converter group grid-connected system, which comprises the steps of firstly establishing an equivalent circuit model of a single converter original circuit model, then establishing a distributed converter group grid-connected simulation system model comprising a plurality of Norton equivalent circuits, and adopting a comprehensive converter switch and support capacitor equivalent modeling technology and a distributed converter group grid-connected system high-efficiency simulation method of the converter Noton equivalent technology. The high-efficiency simulation method of the large-scale converter group distributed grid-connected system is simple in modeling method, high in universality and high in simulation efficiency and precision, and can simulate the internal electrical transient characteristics of the converter.
Description
Technical Field
The invention relates to the technical field of power electronic simulation modeling, in particular to a high-efficiency simulation method for a converter group distributed grid-connected system.
Background
With the development of power electronic technology and the increase of application requirements, the scale of a converter group grid-connected system is larger and larger, such as a vehicle grid system, a wind power plant, a photovoltaic power station and the like. Due to the fact that the number of the converters is large, the interaction mechanism between the converters and a power grid is complex, the optimal matching of the converters and the power grid and the coordination control difficulty of a converter group are high, once an accident happens, a large number of devices are damaged, economic losses are huge, repair cost is high, and the time period is long. Therefore, the safe, stable and reliable operation of the large-scale converter group distributed grid-connected system is very important.
The inventor provides a high-efficiency simulation method for multi-converter centralized grid connection in a high-efficiency simulation method of a multi-converter centralized grid connection system, but the method is not suitable for distributed grid connection of converter groups:
(1) the grid-connected positions of all the converters of the multi-converter centralized grid-connected system are the same point, so the switch equivalent admittances of all the converters are consistent and are all GsTherefore, the node admittance matrixes of all the current transformers are consistent; when the converter group is in distributed grid connection, different grid connection positions of the converters have influence on the switch equivalent admittance, namely the switch equivalent admittance of the converters at different positions is different, so that node admittance matrixes of the converters are inconsistent.
(2) According to the high-efficiency simulation method of the multi-converter centralized grid-connected system, a plurality of converters are simplified and combined into a model with 2 nodes and 2 branches; the original ultra-large scale admittance matrix is reduced to 2 low-order matrices (admittance matrices of an equivalent circuit of a multi-converter centralized grid-connected system and unified node admittance matrices of all converters), and only two low-order constant matrices with fixed orders need to be generated and inverted during the initial simulation; when the converter groups are distributed and connected to the grid, each converter is simplified into a model with 2 nodes and 2 branches, but the models cannot be combined because the positions are not the same, so that the original ultra-large scale admittance matrix is reduced into a plurality of low-order matrixes, and a plurality of low-order constant matrixes with fixed orders need to be generated and inverted during the initial simulation.
(3) According to the high-efficiency simulation method of the multi-converter centralized grid-connected system, switches and supporting capacitors of a converter are equivalent to current source parallel admittances according to a trapezoidal integration method, however, the trapezoidal method has the defects that: (a) the converter switching state may cause numerical oscillation; (b) the equivalent current source of the converter is related to the current flowing through the switch and the voltage at two ends of the switch; (c) the current flowing through the switch or the capacitor of the converter needs to be calculated, and the calculation amount is large.
In view of the defects, the invention provides the high-efficiency simulation method of the large-scale converter group distributed grid-connected system, which is simple in modeling method, strong in universality, high in simulation efficiency and precision and capable of simulating the internal electrical transient characteristics of the converter.
Disclosure of Invention
The invention aims to provide a high-efficiency simulation method of a converter group distributed grid-connected system, which is suitable for the converter group (IGBT, thyristor, diode, ideal switch and the like) distributed grid-connected system of any power electronic switch.
In order to achieve the purpose, the technical scheme of the invention is a high-efficiency simulation method of a distributed grid-connected system of a converter group, which comprises the following steps:
step 1, before simulation begins, setting simulation step length delta t and total simulation duration tfThe converter and the converter group distributed grid-connected system have various parameters;
step 2, calculating equivalent admittance of a converter switch and a support capacitor: establishing an original model of a single converter according to the position of the converter connected to a power grid, simplifying each converter into an equivalent model of 2 nodes and 2 branches, debugging and determining the switch equivalent admittance of each converter through simulation comparison, and marking as Gs1、Gs2、Gsk......GsxX is the number of the current transformers, and k is any one of the current transformers;
the method comprises the following steps of firstly establishing an equivalent circuit model of a single converter original circuit model, and then establishing a converter group distributed grid-connected simulation system model comprising a plurality of Norton equivalent circuits, wherein the method specifically comprises the following steps: based on a backward Euler method and the on/off characteristics of the power electronic switch, a branch of a current source parallel admittance is deduced and adopted to simulate the power electronic switch (a diode, an IGBT, a thyristor, an ideal switch and the like), a support capacitor and the like in the converter, and when the switch is switched on, the calculation is carried out according to the following relational expression:
ik1(t)＝imn(t-Δt) (1)
when the switch is off, it is calculated by the following relation:
ik1(t)＝-Gsk×Vmn(t-Δt) (2)
in the formula, GskIs a constant greater than 0 and less than 1, imnThe current flowing through the kth converter switching tube in the m and n endpoints; i.e. ik1、VmnThe voltage of the current source and the voltage of the two ends of the current source are respectively connected with the m end point and the n end point; t is simulation time; and delta t is the simulation time step.
For the support capacitance, it is calculated by the following relation:
in the formula ikc、GscAn equivalent current source and an admittance which are respectively a support capacitor of the kth converter; c is the value of the support capacitance; vmoIs the voltage between the m and o terminals.
Step 3, building each converter node admittance matrix shown in the vertical type (4); according to the Noton theorem, calculating to obtain the equivalent admittance G of the Noton equivalent circuit of each converter1、G2......GX；
In the formula, Vm、Vn、VpVoltages of the node m, the node n and the node p to the reference node respectively; and in the same way, the node admittance network equations of other converters can be obtained.
Step 4, establishing a node admittance matrix of the equivalent circuit of the converter group distributed grid-connected system;
step 5, initializing the on-off state of each converter and the voltage flowing through the switch and the two ends of the switch at the t-delta t moment when the simulation initial moment is t; initializing voltages at two ends of each converter supporting capacitor at the t-delta t moment;
step 6, calculating the equivalent current of each switch of each converter at the time t through the formulas (1) to (2) according to each switch state of each converter and the converter switch and support capacitor equivalent admittance calculated in the step 2; calculating equivalent current i of each converter supporting capacitor at the time t by the formula (3)1、i2......ix；
Step 7, calculating to obtain equivalent current sources of the Norton equivalent circuits of the converters according to the Norton theorem;
step 8, solving a node admittance network equation of the converter group distributed grid-connected system equivalent circuit according to the system node admittance matrix obtained in the step 4 and the equivalent current source of the Norton equivalent circuit of each converter obtained in the step 7, and calculating to obtain the grid-side voltage V of each converters1、VS2......VSX；
Step 9, calculating the network side voltage V of each converters1、VS2......VSXSubstituting the current, the voltage at two ends of the switch and the voltage at two ends of the supporting capacitor of each converter at the time t into the node admittance network equation of each converter established in the step 3, and solving by adopting a formula (4);
step 10, i ═ t + Δ t, and determine whether the simulation duration exceeds the set total simulation duration tfIf not, the switch of each converter is controlled, and the switch state of each converter is determined by combining the power electronic switch characteristics, and the step 6 is carried out; e.g. exceeding tfAnd ending the simulation.
Has the advantages that:
(1) the efficient simulation method of the converter group distributed grid-connected system is used for integrating the converter switch and support capacitor equivalent modeling technology and the converter Noton equivalent technology.
(2) Each converter is equivalent to a branch with a historical current source and an admittance connected in parallel, then an electromagnetic transient solving process with a simulation step length is carried out in conjunction with a power grid, and then various electric quantities of an internal switch and a supporting capacitor of each converter at each simulation moment are calculated according to the power grid voltage of each converter obtained through solving and a node admittance network equation of each converter.
(3) The converter switch and the supporting capacitor are equivalent to a current source parallel admittance, and the admittance value is unchanged when the switch state changes, and only the value of the current source is changed, the scheme ensures that the Nonton equivalent resistance of each converter is a fixed constant, so that only a node admittance matrix of the converter group and the power grid, and an admittance matrix of each converter are generated and inverted once at the initial simulation time, namely, the node admittance matrix of the converter group grid-connected system and the node admittance matrix of each converter do not need to be re-generated and inverted in each subsequent simulation step no matter how the states of a large number of converter switch devices change in the simulation process, and thus, the time for generating the node admittance matrix of the converter group grid-connected system, the node admittance matrix of each converter and respective inversion can be greatly saved.
(4) Each converter is equivalent to a current source parallel admittance, so that each multi-node and multi-branch converter model is simplified into a simplified model of 2 nodes and 2 branches, and the operation amount is greatly reduced.
(5) The current converters are equivalent to current source parallel admittance, so that natural decoupling between a power grid and a current converter group and between the power grid and the current converters is realized, the current converters can be detached from any strong coupling position, virtual resistance does not need to be added for assisting decoupling, the decoupling position is flexible, and the problem of numerical value oscillation or accuracy reduction caused by adding the virtual resistance is avoided.
(6) The invention reduces the original super-large scale admittance matrix into a plurality of low-order matrixes, and only needs to invert a plurality of low-order constant matrixes with fixed orders simultaneously in the simulation process, thereby avoiding directly inverting the high-order matrixes, and obviously reducing the calculation time.
(7) Based on the euler's method of retreating, become the parallelly connected admittance of current source with the switch of converter and support electric capacity equivalence, for trapezoidal method, its advantage lies in: (a) the backward Euler method can effectively avoid numerical value oscillation caused by switching of the on-off state of the converter; (b) the equivalent current source of the converter is only related to the current flowing through the switch or the voltage at two ends of the switch, and the trapezoidal method is related to the current flowing through the switch or the voltage at two ends of the switch; (c) the switch-off of the converter switch or the equivalent current source of the converter supporting capacitor is only related to the voltage at two ends, so that the calculation of the current flowing through the converter switch or the capacitor is avoided, and the calculation amount is reduced.
(8) The high-efficiency simulation method provided by the invention has strong universality and is suitable for the distributed grid-connected system of a converter group (IGBT, a thyristor, a diode, an ideal switch and the like) of any power electronic switch; the algorithm organization is simple, the simulation efficiency and the simulation precision are high, and the behavior characteristics of a large simulation system and the internal electrical transient characteristics of the converter module can be considered.
Drawings
Fig. 1 is a primary structure diagram of a distributed grid-connected system of a converter group.
Fig. 2 shows the topology of the kth converter.
Fig. 3 is an equivalent circuit of the switch and the support capacitor of the kth converter.
Fig. 4 shows the norton equivalent circuit of the kth converter.
Fig. 5 is an equivalent circuit of the converter group distributed grid-connected system.
Detailed Description
It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, rather than all embodiments, and all other embodiments obtained by a person of ordinary skill in the art without any creative work based on the embodiments of the present invention belong to the protection scope of the present invention.
The technical scheme of the invention is a high-efficiency simulation method of a distributed grid-connected system of a converter group, which comprises the following steps:
s1, before simulation begins, setting simulation step length, total simulation duration and parameters of the multi-converter centralized grid-connected system, wherein the parameters of the multi-converter centralized grid-connected system comprise a power grid, a support capacitor of a converter and the like;
s2, calculating equivalent admittance of switches (any one of diode, IGBT, thyristor and ideal switch) and supporting capacitor unified by all current transformers: establishing an equivalent circuit model of a single converter according to the position of the converter connected to a power grid, and debugging and determining the switch equivalent admittance of the converter through simulation comparison; determining the equivalent admittance of a current transformer support capacitor;
s3, establishing a unified node admittance matrix of all the current transformers; calculating to obtain the uniform equivalent admittance of the Norton equivalent circuit of all the converters according to the Norton theorem;
s4, establishing an equivalent circuit of the multi-converter centralized grid-connected system;
s5, recording simulation initial time, initializing the switch state of each converter and the current simulation time, and reducing one simulation step length to flow switch current, voltage at two ends of a switch and voltage at two ends of a supporting capacitor of each converter;
s6, calculating the equivalent current of each switch of each current transformer at the moment according to each switch state of each current transformer and the equivalent admittance of the current transformer switch and the support capacitor calculated in the step 2; calculating the equivalent current of each converter supporting capacitor at the moment;
s7, calculating the equivalent current source of the Norton equivalent circuit of each converter according to the Norton theorem.
s8, solving a node admittance network equation of the equivalent circuit of the multi-converter centralized grid-connected system established in the step 4 according to the system node admittance matrix obtained in the step 3 and the equivalent current source of the norton equivalent circuit of each converter obtained in the step 7, and calculating to obtain the uniform grid-side voltage of all the converters;
s9, substituting the calculated unified network side voltages of all the converters into each converter node admittance network equation, and solving to obtain the current flowing through each switch of each converter, the voltages at two ends of the switch and the voltages at two ends of the supporting capacitor;
s10, adding a simulation step length moment at the current simulation moment, judging whether the simulation duration exceeds the set total simulation duration, if not, controlling the simulation duration by the switches of the converters, determining the switch states of the converters by combining the characteristics of the power electronic switches, and going to step 6; if so, the simulation ends.
In the first embodiment, as shown in fig. 1 and fig. 2, the original structure diagram of the distributed grid-connected system of the converter group and the topology structure diagram of the kth converter are respectively shown, in the diagram, Vs、iskRespectively, the grid side voltage and the grid side current of the kth converter.
Based on the backward Euler method and the on/off characteristics of the power electronic switch, the invention deduces and adopts the branch of the current source parallel admittance to simulate the power electronic switch (diode, IGBT, thyristor, ideal switch, etc.), the support capacitor, etc. in the converter, as shown in FIG. 3 (from left to right, the power electronic switch 1, the power electronic switch 2, the power electronic switch 3, the power electronic switch 4, the support capacitor, m, n, o, p are nodes at two ends of the component, n is the input end of the equivalent circuit, p is the output end of the equivalent circuit in sequence from top to bottom), the on or off state of each type of power electronic switch is determined by the external control and the characteristics of the power electronic switch. The equivalent admittance Gsk of the switch in fig. 3 is a constant greater than 0 and smaller than 1, the state of the switch has no influence on the equivalent admittance Gsk, but the equivalent admittance Gsk of the switch has influence on the equivalent admittance Gsk of the converter at different grid-connected positions, i.e. the equivalent admittance Gsk of the converter at different positions is different; the state of the switch affects the current source, i in FIG. 3k1～ik4The equivalent current sources of switches 1 to 4, respectively, take the current source connected at m and n points as an example, when the switches are turned on, the following relations are derived:
ik1(t)＝imn(t-Δt) (1)
when the switch is off, there is the following relationship:
ik1(t)＝-Gsk×Vmn(t-Δt) (2)
in the formula (I), the compound is shown in the specification,imn is the current flowing through the converter switch 1; i.e. ik1、VmnThe voltage of the current source and the voltage of the two ends of the current source are respectively connected with the m end point and the n end point; t is simulation time; and delta t is the simulation time step.
For the support capacitance, there is the following relationship:
in the formula ikc、GscAn equivalent current source and an admittance which are respectively a current transformer supporting capacitor; c is the value of the support capacitance; vmoIs the voltage between the m and o terminals.
According to fig. 3, based on the improved node method, the node admittance network equation of the kth converter can be written as follows:
in the formula, Vm、Vn、VpThe voltages of the node m, n and p points to the reference node O. And in the same way, the node admittance network equations of other converters can be obtained.
From fig. 3, the norton equivalent circuit of the kth converter can be obtained, as shown in fig. 4.
In FIG. 4, a current source ikIs the short circuit current when the ports n, p of fig. 5 are short circuited; gkThe input admittances after setting 0 for all independent sources inside the ports n, p of fig. 4.
The converter model of fig. 2 is replaced by the converter norton equivalent circuit of fig. 4 for each converter of fig. 1, and then the converter norton equivalent circuits are combined to obtain the converter group distributed grid-connected system equivalent circuit, as shown in fig. 5:
in FIG. 5, ix、GX、VSXRespectively representing the Noton equivalent current source, admittance and network side input voltage of each converter, x belongs to N+。
According to the modeling, the efficient simulation method for the distributed grid-connected system of the converter group comprises the following steps:
(1) setting simulation step length delta t and total simulation duration tfParameters such as the support capacitance of the power grid and the converter;
(2) and (3) calculating equivalent admittance of a converter switch and a support capacitor: (a) according to the access positions of the converters, the power grid is respectively connected with the original model of the converter in the figure 2 and the equivalent model in the figure 3, through simulation comparison,debugging and determining the switch equivalent admittance of each converter, which is marked as Gs1、Gs2、Gsk......GsxB, carrying out the following steps of; (b) determining equivalent admittance G of current transformer support capacitance by formula (3)SC；
(3) Building a node admittance matrix of each current transformer shown in the vertical type (4); according to the Noton theorem, calculating to obtain the equivalent admittance G of the Noton equivalent circuit unified by all the current transformers1、G2......GX；
(4) Establishing a node admittance matrix of an equivalent circuit of the multi-converter centralized grid-connected system shown in fig. 5;
(5) the simulation initial time is t, and the on-off state of each converter and the voltage flowing through the switch and the voltage at two ends of the switch at the t-delta t time are initialized; initializing voltages at two ends of each converter supporting capacitor at the t-delta t moment;
(6) calculating the equivalent current of each switch of each current transformer at the time t through the formulas (1) to (2) according to each switch state of each current transformer and the equivalent admittance of the current transformer switch and the support capacitor calculated in the step 2; calculating equivalent current i of each converter supporting capacitor at the time t by the formula (3)1、i2......ix；
(7) Calculating to obtain equivalent current sources of the Norton equivalent circuits of the converters according to the Norton theorem;
(8) solving a node admittance network equation of the converter group distributed grid-connected system equivalent circuit shown in the figure 5 according to the system node admittance matrix obtained in the step 4 and the equivalent current source of the Norton equivalent circuit of each converter obtained in the step 7, and calculating to obtain the grid-side voltage V of each converters1、VS2......VSX；
(9) Calculating the network side voltage V of each converters1、VS2......VSXSubstituting the current, the voltage at two ends of the switch and the voltage at two ends of the supporting capacitor of each converter at the time t into the node admittance network equation of each converter established in the step 3, wherein the equation is similar to the equation (4);
(10) t ═ t + Δ t, and it is determined whether the simulation duration exceeds a set total simulation duration tfIf not, by individual convertersSwitching control is carried out, the switching state of each converter is determined by combining the characteristics of power electronic switches, and the step 6 is carried out; e.g. exceeding tfAnd ending the simulation.
The high-efficiency simulation method provided by the invention has strong universality and is suitable for a multi-converter centralized grid-connected system of any power electronic switch (IGBT, thyristor, diode, ideal switch and the like); the algorithm organization is simple, the simulation efficiency and the simulation precision are high, and the behavior characteristics of a large simulation system and the internal electrical transient characteristics of the converter module can be considered.
The above description is only a preferred embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications of equivalent structures and equivalent processes, which are made by using the contents of the present specification and the accompanying drawings, or directly or indirectly applied to other related technical fields, are included in the scope of the present invention.
Claims (4)
1. A converter group distributed grid-connected system high-efficiency simulation method is characterized in that an equivalent circuit model of a single converter original circuit model is established, then a converter group distributed grid-connected simulation system model comprising a plurality of Norton equivalent circuits is established, wherein the equivalent circuit model for establishing the single converter actual circuit model is based on a backward Euler method and the on/off characteristics of a power electronic switch, 2 nodes of current source parallel admittance and 2 branches are deduced and adopted to establish equivalent circuits of the power electronic switch and a support capacitor in the converter; establishing a Norton equivalent circuit of a single converter, and replacing an actual circuit of the converter by the Norton equivalent circuit to obtain a converter group distributed grid-connected simulation system model;
the simulation is carried out through the simulation system model, and the method comprises the following steps:
step 1, before simulation begins, setting simulation step length delta t and total simulation duration tfThe converter and the converter group distributed grid-connected system have various parameters;
step 2, calculating equivalent admittance of a converter switch and a support capacitor: according to the position of the converter connected to the power grid, the power grid is respectively connected with the original model and the equivalent circuit model of the single converter, and the simulation is carried out on the modelsComparing, debugging and determining switch equivalent admittance G of each converters1、Gs2、Gsk......GsxX is the number of the current transformers, and k is any one of the current transformers;
step 3, establishing an admittance matrix of each converter node; according to the Noton theorem, calculating to obtain the equivalent admittance G of the Noton equivalent circuit of each converter1、G2......GX；
Step 4, establishing a node admittance matrix of the equivalent circuit of the converter group distributed grid-connected system;
step 5, initializing the on-off state of each converter and the voltage flowing through the switch and the two ends of the switch at the t-delta t moment when the simulation initial moment is t; initializing voltages at two ends of each converter supporting capacitor at the t-delta t moment;
and 6, calculating the equivalent current of each switch of each converter at the time t and the equivalent current i of each converter supporting capacitor at the time t according to each switch state of each converter and the equivalent admittance of each converter switch and each supporting capacitor calculated in the step 21、i2......ix；
Step 7, calculating to obtain equivalent current sources of the Norton equivalent circuits of the converters according to the Norton theorem;
step 8, solving a node admittance network equation of the converter group distributed grid-connected system equivalent circuit according to the system node admittance matrix obtained in the step 4 and the equivalent current source of the Norton equivalent circuit of each converter obtained in the step 7, and calculating to obtain the grid-side voltage V of each converters1、VS2......VSX；
Step 9, calculating the network side voltage V of each converters1、VS2......VSXSubstituting the current into each converter node admittance network equation established in the step 3, and calculating the current flowing through each switch of each converter at the moment t, the voltage at two ends of each switch and the voltage at two ends of each supporting capacitor;
step 10, t ═ t + Δ t, and determine whether the simulation duration exceeds the set total simulation duration tfIf not, the switching control of each converter is used in combination with the power electronic switching characteristics to determine the switching state of each converter, andgo to step 6; e.g. exceeding tfAnd ending the simulation.
2. The distributed grid-connected system high-efficiency simulation method of the converter group according to claim 2, wherein the switch comprises any one of a diode, an IGBT, a thyristor and an ideal switch.
3. The distributed grid-connected system high-efficiency simulation method of the converter group according to claim 2, wherein a branch of a current source parallel admittance is derived and adopted to simulate an internal power electronic switch and a support capacitor of the converter based on a backward eulerian method and on/off characteristics of the power electronic switch, an equivalent circuit comprises four equivalent current sources and admittances connected in parallel, and when the switch is turned on, a corresponding equivalent current flowing through the equivalent circuit is calculated according to the following relational expression:
ik1(t)＝imn(t-Δt) (1)
when the switch is off, the equivalent current is calculated by the following relation:
ik1(t)＝-Gsk×Vmn(t-Δt) (2)
in the formula, GskIs a constant greater than 0 and less than 1, imnThe current flowing through the kth converter switching tube in the m and n endpoints; i.e. ik1、VmnThe voltage of the current source and the voltage of the two ends of the current source are respectively connected with the m end point and the n end point; t is simulation time; delta t is the simulation time step length;
for the support capacitance, the corresponding equivalent current and equivalent admittance are calculated by the following relations:
in the formula ikc、GscAn equivalent current source and an admittance which are respectively a support capacitor of the kth converter; c is the value of the support capacitance; vmoIs the voltage between the m and o terminals.
4. The distributed grid-connected system high-efficiency simulation method of the converter group as claimed in claim 2, wherein based on the improved node method, the node admittance network equation of the kth converter is as follows (4):
in the formula, Vm、Vn、VpVoltages of the node m, the node n and the node p to the reference node respectively; and similarly, obtaining node admittance network equations of other converters, and calculating the network side voltage of each converter through the formula (4).
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN110021929A (en) * | 2018-12-29 | 2019-07-16 | 国网内蒙古东部电力有限公司经济技术研究院 | A kind of high-speed switch type fault current limiter electro-magnetic transient time-domain-simulation modeling method |
| CN110895644A (en) * | 2018-09-12 | 2020-03-20 | 中车株洲电力机车研究所有限公司 | Simulation system for large-scale converter group grid connection and equivalent circuit of converter |
| US20210049313A1 (en) * | 2019-08-16 | 2021-02-18 | Shanghai Jiao Tong University | Electromagnetic transient simulation method for field programmable logic array |
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| CN110895644A (en) * | 2018-09-12 | 2020-03-20 | 中车株洲电力机车研究所有限公司 | Simulation system for large-scale converter group grid connection and equivalent circuit of converter |
| CN110021929A (en) * | 2018-12-29 | 2019-07-16 | 国网内蒙古东部电力有限公司经济技术研究院 | A kind of high-speed switch type fault current limiter electro-magnetic transient time-domain-simulation modeling method |
| US20210049313A1 (en) * | 2019-08-16 | 2021-02-18 | Shanghai Jiao Tong University | Electromagnetic transient simulation method for field programmable logic array |
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