CN112597731A - Electromagnetic transient simulation method and device for current transformer, electronic equipment and storage medium - Google Patents
Electromagnetic transient simulation method and device for current transformer, electronic equipment and storage medium Download PDFInfo
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- CN112597731A CN112597731A CN202110237541.6A CN202110237541A CN112597731A CN 112597731 A CN112597731 A CN 112597731A CN 202110237541 A CN202110237541 A CN 202110237541A CN 112597731 A CN112597731 A CN 112597731A
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Abstract
The application provides a converter electromagnetic transient simulation method and device, electronic equipment and a storage medium, and relates to the technical field of transient simulation. Firstly, performing norton equivalence on devices in a converter, and then acquiring states, driving signals, terminal voltages, branch currents and bridge arm currents of an equivalent switch group and an equivalent independent diode in a previous time step; determining the initial state of the switch group and the independent diode in the current time step according to the state, the driving signal, the terminal voltage and the branch current in the previous time step; updating the states of the switch group and the independent diode according to the state and the initial state in the previous time step and the bridge arm current, and taking the updated states as the states of the switch group and the independent diode in the current time step; then, the process of the preliminary judgment and the state updating is repeatedly executed until a preset time step is reached; and finally, performing electromagnetic transient simulation according to the states of the switch group and the independent diodes in all time steps. The method and the device have the advantage of higher simulation efficiency.
Description
Technical Field
The application relates to the technical field of transient simulation, in particular to a converter electromagnetic transient simulation method and device, electronic equipment and a storage medium.
Background
The Neutral Point Clamped (NPC) three-level converter is a power electronic conversion device which is developed rapidly in recent years, and compared with the traditional two-level voltage source converter, the NPC three-level converter has the advantages of small output voltage/current harmonic, low du/dt bearing of a switching device, small switching loss, and capability of effectively reducing the volume and weight of a filter. Therefore, the NPC three-level converter is widely applied to occasions such as a medium-low voltage photovoltaic/energy storage/wind power generation system, a multiphase motor dragging system, a high-speed railway power supply system and the like.
In order to study the transient steady-state characteristics and the control protection strategy of the NPC three-level converter, analog calculation and analysis are required to be carried out on the working state of the NPC three-level converter by means of a digital electromagnetic transient simulation tool. At present, the commercially available off-line electromagnetic transient simulation software mainly comprises simpower system, ADPSS, cloudbs and the like of PSCAD and Matlab.
However, when the current converter is subjected to electromagnetic transient simulation, an iteration method needs to be introduced to solve the current switching state with stable time steps, and the circuit topology of the NPC three-level converter comprises a large number of switching tubes and diode elements, so that the iteration process is long in time consumption, and the simulation efficiency is low.
In summary, the current electromagnetic transient simulation method of the converter has the problems of long time consumption and low efficiency.
Disclosure of Invention
The application aims to provide a converter electromagnetic transient simulation method, a converter electromagnetic transient simulation device, electronic equipment and a storage medium, so as to solve the problems of long time consumption and low efficiency of the converter electromagnetic transient simulation method in the prior art.
In order to achieve the above purpose, the embodiments of the present application employ the following technical solutions:
in a first aspect, an embodiment of the present application provides a converter electromagnetic transient simulation method, where the method includes:
performing Norton equivalence on devices in the converter, wherein the converter comprises a switch group and an independent diode, and the switch group comprises a switch tube and a combined diode;
obtaining the state, the driving signal, the terminal voltage, the branch current and the bridge arm current of the equivalent switch group and the equivalent independent diode in the previous time step;
determining the initial state of the switch group and the independent diode in the current time step according to the state, the driving signal, the terminal voltage and the branch current in the previous time step;
updating the states of the switch group and the independent diode according to the state in the previous time step, the initial state and the bridge arm current, and taking the updated states as the states of the switch group and the independent diode in the current time step;
the process of preliminary judgment and state updating is repeatedly executed until a preset time step is reached;
and performing electromagnetic transient simulation according to the states of the switch group and the independent diode at all time steps.
In a second aspect, an embodiment of the present application provides a converter electromagnetic transient simulation apparatus, where the apparatus includes:
the converter comprises a converter, a Norton equivalent unit, a converter control unit and a control unit, wherein the Norton equivalent unit is used for carrying out Norton equivalence on devices in the converter, the converter comprises a switch group and an independent diode, and the switch group comprises a switch tube and a combined diode;
the parameter acquisition unit is used for acquiring the state, the driving signal, the terminal voltage, the branch current and the bridge arm current of the equivalent switch group and the equivalent independent diode in the previous time step;
the state determining unit is used for determining the initial state of the switch group and the independent diode in the current time step according to the state, the driving signal, the terminal voltage and the branch current in the previous time step;
the state updating unit is used for updating the states of the switch group and the independent diode according to the state in the previous time step, the initial state and the bridge arm current, and taking the updated states as the states of the switch group and the independent diode in the current time step;
the state determining unit and the state updating unit are also used for repeatedly executing the processes of preliminary judgment and state updating until a preset time step is reached;
and the simulation unit is used for performing electromagnetic transient simulation according to the states of the switch group and the independent diode in all time steps.
In a third aspect, an embodiment of the present application provides an electronic device, which includes a memory for storing one or more programs; a processor. The one or more programs, when executed by the processor, implement the converter electromagnetic transient simulation method described above.
In a fourth aspect, the present application provides a computer-readable storage medium, on which a computer program is stored, and the computer program, when executed by a processor, implements the above-mentioned electromagnetic transient simulation method for a current transformer.
Compared with the prior art, the method has the following beneficial effects:
the application provides a converter electromagnetic transient simulation method, a converter electromagnetic transient simulation device, electronic equipment and a storage medium, wherein the converter is subjected to Norton equivalence on devices in the converter, wherein the converter comprises a switch group and an independent diode, and the switch group comprises a switch tube and a combined diode; then obtaining the state, the driving signal, the terminal voltage, the branch current and the bridge arm current of the equivalent switch group and the equivalent independent diode in the last time step; determining the initial state of the switch group and the independent diode in the current time step according to the state, the driving signal, the terminal voltage and the branch current in the previous time step; updating the states of the switch group and the independent diode according to the state and the initial state in the previous time step and the bridge arm current, and taking the updated states as the states of the switch group and the independent diode in the current time step; then, the process of the preliminary judgment and the state updating is repeatedly executed until a preset time step is reached; and finally, performing electromagnetic transient simulation according to the states of the switch group and the independent diodes in all time steps. Because the stable switch state is directly determined at the current time step, the iterative process of solving the stable switch state in the traditional electromagnetic transient simulation is eliminated, the simulation precision equivalent to that of the traditional detailed model can be ensured, the simulation time consumption is remarkably reduced, and the simulation efficiency is higher.
In order to make the aforementioned objects, features and advantages of the present application more comprehensible, preferred embodiments accompanied with figures are described in detail below.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are required to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present application and therefore should not be considered as limiting the scope, and it will be apparent to those skilled in the art that other related drawings can be obtained from the drawings without inventive effort.
Fig. 1a is a circuit diagram of a converter in the prior art, and fig. 1b is an equivalent schematic diagram of an averaging modeling method.
Fig. 2 is a schematic block diagram of an electronic device according to an embodiment of the present application.
Fig. 3 is a schematic flowchart of a converter electromagnetic transient simulation method according to an embodiment of the present application.
Fig. 4a is a topology structure of a half-bridge type NPC converter, and fig. 4b is a norton equivalent schematic diagram of the half-bridge type NPC converter.
Fig. 5a is a schematic diagram of a switching tube according to an embodiment of the present application, and fig. 5b is a schematic diagram of a diode according to an embodiment of the present application.
Fig. 6a is a schematic diagram before a first switch state provided in the embodiment of the present application is changed, and fig. 6b is a schematic diagram after the first switch state provided in the embodiment of the present application is changed.
Fig. 7a is a schematic diagram before a second switch state provided in the embodiment of the present application is changed, and fig. 7b is a schematic diagram after the second switch state provided in the embodiment of the present application is changed.
Fig. 8a is a schematic diagram before a state of a third switch provided in the embodiment of the present application is changed, and fig. 8b is a schematic diagram after the state of the third switch provided in the embodiment of the present application is changed.
Fig. 9a is a schematic diagram before a fourth switch state provided in the embodiment of the present application is changed, and fig. 9b is a schematic diagram after the fourth switch state provided in the embodiment of the present application is changed.
Fig. 10a is a schematic diagram before a fifth switch state provided in the embodiment of the present application is changed, and fig. 10b is a schematic diagram after the fifth switch state provided in the embodiment of the present application is changed.
Fig. 11a is a schematic diagram before a state change of a sixth switch provided in the embodiment of the present application, and fig. 11b is a schematic diagram after the state change of the sixth switch provided in the embodiment of the present application.
Fig. 12a is a schematic diagram before a state change of a seventh switch provided in the embodiment of the present application, and fig. 12b is a schematic diagram after the state change of the seventh switch provided in the embodiment of the present application.
Fig. 13a is a schematic diagram before a state change of an eighth switch provided in the embodiment of the present application, and fig. 13b is a schematic diagram after the state change of the eighth switch provided in the embodiment of the present application.
Fig. 14 is a schematic block diagram of a converter electromagnetic transient simulation apparatus according to an embodiment of the present application.
In the figure: 100-an electronic device; 101-a processor; 102-a memory; 103-a communication interface; 300-converter electromagnetic transient simulation device; 310-norton equivalent cell; 320-a parameter obtaining unit; 330-a state determination unit; 340-a state update unit; 350-simulation unit.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are some embodiments of the present application, but not all embodiments. The components of the embodiments of the present application, generally described and illustrated in the figures herein, can be arranged and designed in a wide variety of different configurations.
Thus, the following detailed description of the embodiments of the present application, presented in the accompanying drawings, is not intended to limit the scope of the claimed application, but is merely representative of selected embodiments of the application. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.
It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures. Meanwhile, in the description of the present application, the terms "first", "second", and the like are used only for distinguishing the description, and are not to be construed as indicating or implying relative importance.
It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.
In the description of the present application, it should be noted that the terms "upper", "lower", "inner", "outer", and the like indicate orientations or positional relationships based on orientations or positional relationships shown in the drawings or orientations or positional relationships conventionally found in use of products of the application, and are used only for convenience in describing the present application and for simplification of description, but do not indicate or imply that the referred devices or elements must have a specific orientation, be constructed in a specific orientation, and be operated, and thus should not be construed as limiting the present application.
In the description of the present application, it is also to be noted that, unless otherwise explicitly specified or limited, the terms "disposed" and "connected" are to be interpreted broadly, e.g., as being either fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present application can be understood in a specific case by those of ordinary skill in the art.
Some embodiments of the present application will be described in detail below with reference to the accompanying drawings. The embodiments described below and the features of the embodiments can be combined with each other without conflict.
As described in the background art, in order to study the transient-steady-state characteristics and the control protection strategy of the NPC three-level converter, analog calculation and analysis of the operating state of the NPC three-level converter are required by using a digital electromagnetic transient simulation tool. At present, the commercially available off-line electromagnetic transient simulation software mainly comprises simpower system, ADPSS, cloudbs and the like of PSCAD and Matlab.
However, the circuit topology of the NPC three-level converter includes a large number of switching tubes and diode elements, for example, 120 switching tubes and 180 diode elements are adopted in a fifteen-phase motor dragging system based on the full-bridge NPC three-level converter, and there is a problem of serious computation time consumption when the conventional electromagnetic transient modeling method is adopted to simulate the three-phase motor dragging system, and the main reason is that:
(1) the switching frequency of the NPC three-level converter is usually kilohertz, in order to accurately simulate the switching process, the simulation step length needs to be set to be 1/20-1/100 of the switching period, namely 10 us-50 us, and the smaller the simulation step length is, the higher the simulation time consumption is.
(2) In the simulation calculation process, the NPC three-level converter acts according to a certain switching sequence. In a certain step of calculation, some switching actions may result in a series of interlocked switching actions at the same time. At this time, an iterative method is required to solve the stable switching state of the current time step. As the number of switches of the circuit increases, the iterative process time consumption will increase dramatically.
In order to realize rapid electromagnetic transient simulation of the converter, an average modeling method of an NPC three-level converter is adopted to realize electromagnetic transient simulation of the converter in the prior art.
For example, referring to fig. 1, a circuit diagram of the NPC three-level converter is shown in fig. 1a, an averaging modeling method of the NPC three-level converter has a good effect in improving the simulation calculation efficiency, and an equivalent circuit diagram thereof is shown in fig. 1 b. The current/voltage value in a switching period is equivalent by the average value thereof through the impulse equality principle, which specifically comprises the following steps: the direct current side of the converter is equivalent to a controllable current source, the alternating current side is equivalent to a controllable voltage source, and the coupling of the electric quantity of the alternating current side and the direct current side is realized through the following relational expression;
in the formula:
for measuring the voltage value of the equivalent voltage source by alternating current,
、
is the current value of the equivalent current source on the direct current side,
、
is the equivalent voltage of the dc side capacitance,
equivalent current of AC inductance, VmFor modulating the voltage, the value range is [ -1,1 [ ]]。
The switching process is ignored by the average model of the NPC three-level converter, and the average value in the switching period is used for describing the model, so that the simulation can be carried out by adopting a larger step length (the step length can be selected from 100 us-1000 us generally), the simulation calculation efficiency is high, and the method is suitable for simulation analysis of a system level. However, the averaging model is essentially a simplified model that only preserves the external characteristics of the converter, with obvious drawbacks, such as: (1) the switching ripple cannot be simulated; (2) the operation conditions of internal or external faults, modulation mode switching, switch locking and the like of the converter are difficult to simulate; (3) the loss caused by the internal resistance of the switching element of the converter cannot be simulated.
In summary, the problems of low simulation calculation efficiency and large simulation error of the NPC three-level converter exist in the prior art.
In order to solve the above problems, the present application provides a converter electromagnetic transient simulation method, which implements elimination of an iterative process for solving a stable switching state in a conventional electromagnetic transient simulation by directly predicting a stable switching state at a current time step through a transient state, and can remarkably reduce simulation time consumption while ensuring simulation accuracy equivalent to that of a conventional detailed model. Compared with a simplified model based on the averaging modeling, the method keeps the full detailed characteristics of the converter, and can correctly simulate the switching ripple waves, various operation states and loss conditions.
It should be noted that the converter electromagnetic transient simulation method provided by the present application may be applied to an electronic device 100, and fig. 2 illustrates a schematic structural block diagram of the electronic device 100 provided by the embodiment of the present application, where the electronic device 100 includes a memory 102, a processor 101, and a communication interface 103, and the memory 102, the processor 101, and the communication interface 103 are electrically connected to each other directly or indirectly to implement data transmission or interaction. For example, the components may be electrically connected to each other via one or more communication buses or signal lines.
The memory 102 may be used to store software programs and modules, such as program instructions or modules corresponding to the electromagnetic transient simulation apparatus for a converter provided in the embodiment of the present application, and the processor 101 executes the software programs and modules stored in the memory 102 to execute various functional applications and data processing, thereby executing the steps of the electromagnetic transient simulation method for a converter provided in the embodiment of the present application. The communication interface 103 may be used for communicating signaling or data with other node devices.
The Memory 102 may be, but is not limited to, a Random Access Memory (RAM), a Read Only Memory (ROM), a Programmable Read-Only Memory (PROM), an Erasable Read-Only Memory (EPROM), an electrically Erasable Programmable Read-Only Memory (EEPROM), and the like.
The processor 101 may be an integrated circuit chip having signal processing capabilities. The Processor 101 may be a general-purpose Processor, including a Central Processing Unit (CPU), a Network Processor (NP), and the like; but also Digital Signal Processors (DSPs), Application Specific Integrated Circuits (ASICs), Field Programmable Gate Arrays (FPGAs) or other Programmable logic devices, discrete Gate or transistor logic devices, discrete hardware components.
It will be appreciated that the configuration shown in FIG. 2 is merely illustrative and that electronic device 100 may include more or fewer components than shown in FIG. 2 or have a different configuration than shown in FIG. 2. The components shown in fig. 2 may be implemented in hardware, software, or a combination thereof.
The converter electromagnetic transient simulation method provided by the embodiment of the application is exemplarily described below by taking the electronic device 100 as a schematic execution subject.
As an implementation manner, please refer to fig. 3, the electromagnetic transient simulation method of the current transformer includes:
s102, performing Norton equivalence on devices in a current transformer, wherein the current transformer comprises a switch group and an independent diode, and the switch group comprises a switch tube and a combined diode;
s104, acquiring the state, the driving signal, the terminal voltage, the branch current and the bridge arm current of the equivalent switch group and the equivalent independent diode in the previous time step;
s106, determining the initial state of the switch group and the independent diode in the current time step according to the state, the driving signal, the terminal voltage and the branch current in the previous time step;
s108, updating the states of the switch group and the independent diode according to the state and the initial state in the previous time step and the bridge arm current, and taking the updated states as the states of the switch group and the independent diode in the current time step;
and S110, judging whether the preset time step is reached, if so, executing S112, and if not, returning to execute S106.
And S112, performing electromagnetic transient simulation according to the states of the switch group and the independent diodes in all time steps.
The half-bridge type NPC converter is a basic unit of an NPC three-level converter with any number of phases, and the topological structure of the NPC three-level converter is shown in fig. 4 a. In practical circuit application, the middle point of the bridge arm of the half-bridge type NPC converter is also generally connected in series with an inductor or a transformer winding.
In the circuit shown in fig. 4a, the combined diodes are diodes in a switch group, such as D1, D2, D3 and D4, and D1 and switch tube T1 form a first switch group, D2 and switch tube T2 form a second switch group, D3 and switch tube T3 form a third switch group, and D4 and switch tube T4 form a fourth switch group. The independent diodes refer to the diodes independently present in the circuit, such as D5 and D6 in FIG. 4 a. Alternatively, the switch tube described herein may be an Insulated Gate Bipolar Transistor (Insulated Gate Bipolar Transistor).
The norton equivalent process of the half-bridge type NPC converter is as follows: neglecting the forward conduction voltage drop of the switch tube and the diode, the two-state variable resistor R is respectively used for the switch tube and the diode in the figureT、RDInstead. When the switch tube or diode is on, the resistance is very small "On-state "values (typically 0.01 Ω), otherwise very large" off-state "values (typically 1e6 Ω) are taken. Discrete substitution of DC capacitor by Nonton resistor Rc and Nonton current source I by Dommel algorithmhc(history item). Through the above steps, the circuit of the current transformer can be equivalent to the circuit shown in fig. 4 b.
It can be seen that different switch state combinations of the half-bridge NPC converter correspond to different two-state variable resistors, that is, different node admittance matrixes. As long as the accurate judgment of the switch state can be realized in each time step, the accurate transient result can be obtained through simulation. Therefore, an iterative mode is not needed to be adopted for solving, and the accurate judgment of the switch state combination is realized, so that the rapid simulation model is realized.
After the norton equivalent is performed, the resistance value of each device can be determined only by determining the switch state combination because the resistance values of the on state and the off state are determined.
On the basis, the states of the switch group and the independent diodes can be determined through the acquired parameters, and then the resistance values of all the devices are determined.
The states of the switch group and the independent diodes are determined by adopting a mode of preliminary judgment and state updating, so that the current-time-step stable switching state can be directly determined in the transient state simulation method of the converter, and the effect is better.
The circuit diagram of the switch tube and the diode is shown in fig. 5, and the switch tube and the diode respectively have two states of "on" and "off". As shown in FIG. 5a, for the switch tube, assuming that its initial switch state is "off", when the external condition occurs the gate driving signal is "1" and the terminal voltage V isceWhen the voltage is larger than 0, the switch state of the switch is changed into 'on'; assuming that the initial switch state is "on", when an external condition occurs, the gate drive signal is "0" or the branch current iceLess than 0, its switch state will change to "off". As shown in FIG. 5b, for the diode, assume its initial state is "off" when its terminal voltage V isceWhen the voltage is less than 0, the switch state of the switch is changed into 'on'; suppose thatIts initial switch state is "on" when its branch current iceAbove 0, its switch state will change to "off".
Moreover, for the switch group, since the switch tube and the combined diode are connected in parallel in an anti-phase manner, the switch tube and the combined diode cannot be conducted at the same time at any time, so that the switch tube has only three combined switch states, which are respectively defined as:
the first state: the switch tube is closed, and the combined diode is closed;
the second state: the switch tube is closed, and the combined diode is conducted;
the third state: the switch tube is conducted, and the combined diode is closed.
For an individual diode, there are two switching states, defined as:
the first state: the independent diode is turned off;
the first state: the individual diodes conduct.
On this basis, it is understood that the step of S106 includes:
when the switch group is in the third state in the previous time step and the branch current is less than 0, determining that the initial state of the switch group in the current time step is the second state;
when the switch group is in the third state in the previous time step, the branch current is greater than 0 and the driving signal is 0, determining that the initial state of the switch group in the current time step is the first state;
when the switch group is in the second state in the previous time step, the branch current is greater than 0 and the driving signal is 1, determining that the initial state of the switch group in the current time step is the third state;
when the switch group is in the second state in the previous time step, the branch current is greater than 0 and the driving signal is 0, determining that the initial state of the switch group in the current time step is the first state;
when the switch group is in a first state in the previous time step, the terminal voltage is greater than 0 and the driving signal is 1, determining that the initial state of the switch group in the current time step is a third state;
and when the switch group is in the first state in the last time step and the terminal voltage is less than 0, determining that the initial state of the switch group in the current time step is the second state.
It should be noted that the state, the driving signal, the terminal voltage, and the branch current of the previous time step described in this application are all data for the same switching tube.
For example, in the converter circuit shown in fig. 4a, for the switch group consisting of T1 and D1, the initial state can be determined by the branch current i flowing through the switch group in the state of the previous time stepce1And the drive signal G1 determines the initial state of the switch set at the current time step. For the switch group composed of T2 and D2, the initial state can be determined by the state of the switch group in the previous time step, the branch current i flowing through the switch groupce2And the drive signal G2 determines the initial state of the switch set at the current time step.
The following description will be made of the logic for determining the initial state, taking the first switch group consisting of T1 and D1 as an example:
when the initial state of the current time step of the first switch group is determined, the switch state of the previous time step of the first switch group needs to be utilized, for example, when the initial state of the second time step needs to be determined, the switch state of the first time step needs to be acquired. Wherein, the time step can be equivalent to a switching period. Before S106 is executed, the converter needs to be initialized, so that the switching states of all the switch groups are uniform. For example, after initialization, the switch state of each switch group is the first state, and further, when the first switch group determines the initial state of the first time step, the state after initialization of the first switch group may be determined. Meanwhile, it should be noted that the data such as the branch current and the terminal voltage are data at the end of the previous time step, and the initial data of the first switch group at the current time step can be further estimated by using the data.
For example, when the state of the first switch group at the previous time step is the third state, it indicates that the switch tube is turned on and the independent diode is turned off when the first switch group at the previous time step, and at this time, if it is detected that the branch current is less than 0, it indicates that the independent diode will be turned on. If the branch current is greater than 0 and the driving signal is 0, the combined diode is in the off state because the branch current is greater than 0, the driving signal is 0, and the switching tube is also in the off state, so that the initial state of the first switch group at the current time step is changed into the first state.
Similarly, the initial state determination logic is also applicable to other switch groups, so that the initial states of all switch groups at the current time step can be determined.
Meanwhile, for the independent diode, the step of also including the off state and the on state S106 further includes:
when the independent diode is in a conducting state in the previous time step and the branch current is less than 0, determining that the initial state of the independent diode in the current time step is a closing state;
when the independent diode is in a closed state in the previous time step and the branch current is greater than 0, the independent diode is preliminarily judged to be in a conducting state in the current time step.
Through the implementation mode, the initial states of all the switch groups and the independent diodes can be determined according to the current branch voltage/current and the driving signal. However, some switch states in the circuit may be changed simultaneously with the other switch states to interlock, so that it is also necessary to predict the synchronous switching event and update the switch states in combination with the circuit operation state.
On the basis, after the initial states of the switch group and the independent diode are determined, the interlocking action of the switch group and the independent diode can be judged and updated.
As an implementation manner, the converter provided in the present application is an NPC three-level converter, as shown in fig. 4a, the converter includes an upper bridge arm group and a lower bridge arm group, the upper bridge arm group and the lower bridge arm group are symmetrically arranged, the upper bridge arm group includes a first switch group, a second switch group and a fifth diode, and the lower bridge arm includes a third switch group, a fourth switch group and a sixth diode. The first diode is connected with the first end of the first switch group and the second end of the second switch group, the anode of the first diode is connected with the second end of the second switch group, the cathode of the second diode is connected with the common point, and the anode of the third diode is connected with the second end of the third switch group and the anode of the fourth diode.
And the first switch group comprises a first switch tube and a first combined diode, the second switch group comprises a second switch tube and a second combined diode, the third switch group comprises a third switch tube and a third combined diode, and the fourth switch group comprises a fourth switch tube and a fourth combined diode.
On this basis, the step of S108 includes:
when the first switch group is in the third state, the initial state is the first state and the bridge arm current is greater than 0 in the previous time step, the state of the fifth diode is updated to be the conducting state, and the state of the sixth diode is updated to be the off state;
when the second switch group is in the third state, the initial state is the first state and the bridge arm current is greater than 0 in the previous time step, the state of the third switch group is updated to the second state, the state of the fourth switch group is updated to the second state, and the state of the fifth diode is updated to the off state;
when the fourth switch group is in the third state, the initial state is the first state and the bridge arm current is less than 0 in the previous time step, the state of the fifth diode is updated to be the off state, and the state of the sixth diode is updated to be the on state;
when the third switch group is in the third state, the initial state is the first state and the bridge arm current is less than 0 in the previous time step, the state of the first switch group is updated to the second state, the state of the second switch group is updated to the second state, and the state of the sixth diode is updated to the off state.
Namely, as the switch tube is connected with the diode in anti-parallel connection, the switch tube is actively switched on, and the switch-off is the switch-on of the anti-parallel diode. Therefore, the NPC converter synchronous switch event is judged, namely the on-off of all diodes in the NPC converter synchronous switch event is judged, and the judgment is based on the principle of forced freewheeling and forced turn-off of the diodes.
Alternatively, referring to fig. 4, fig. 4 shows a schematic diagram of a combined diode of a switching tube for forced freewheeling. Assuming that the middle point of the arm of the NPC converter is externally connected with an inductive element, and taking the second switch group as an example for description, if the state of the switch group in the previous time step is the "third state", the second switch tube is turned on and the second diode is turned off in the previous time step, at this time, the capacitor C1 may be discharged through the first switch group S1 and the second switch group S2 or through the fifth diode S5 and the second switch group S2, and the lower arm group may be in any state. If the gate signal of the second switching tube T2 is detected to be changed from high to low, the switching state change can be judged to be 'the first state', and the bridge arm current i is at the momenthbFrom the midpoint of the arm to the outer circuit, i.e. ihb>0. It is determined that since the inductor current cannot be interrupted, both the third diode D3 and the fourth diode D4 will be conducting simultaneously to provide a freewheeling path for the leg current ihb. This process is called forced freewheeling, i.e., the states of the third and fourth switch groups S3 and S4 must be forcibly updated to the "second state" regardless of the states (non-stable states) of the third and fourth switch groups S3 and S4 determined by the switch state transition. In addition, the fifth diode D5 will be turned off at the same time due to the turning off of the second switch group. The change condition of the commutation channel in the process is shown in fig. 6, wherein fig. 6a is a schematic diagram before state change, and fig. 6b is a schematic diagram after state change. In the above process, the state change of the second switch group S2 immediately results in the state change process of the third switch group S3, the fourth switch group S4 and the fifth diode D5 being synchronous switching actions. Even if the third and fourth switch groups are determined to be in the third state at the time of initial state determination, the states of the third and fourth switch groups are updated to the second state due to the influence of synchronous switching operation, and the second state is used as the third and fourth switch groupsThe state at the current time step.
Similarly, referring to fig. 7, fig. 7a is a schematic diagram before the state change, and fig. 7b is a schematic diagram after the state change, assuming that the state of the third switch set S3 is the "third state" in the previous time step, if the initial state change in the current time step is the "first state", and there is i at this timehb<0. The first diode D1 and the first diode D2 will be turned on and freewheel, and the states of the first switch group S1 and the second switch group S2 are updated to the "second state", and the state of the sixth diode D6 is updated to the off state.
Meanwhile, referring to fig. 8, fig. 8a is a schematic diagram before a state change, fig. 8b is a schematic diagram after the state change, and the diode forced freewheeling process is further embodied as the conduction freewheeling of the fifth diode D5 and the sixth diode D6. Assuming that the switching state of the first switch group S1 is "third state" at the previous time step, and the bridge arm current ihb >0, the capacitor C1 supplies power to the load through the first switch group S1 and the second switch group S2. If the driving signal of the first switch group S1 is detected to be 0, the switch state thereof is changed to the "first state", and the state of the second switch group S2 is still the "third state". It can be determined that, since the inductor current cannot be interrupted, the fifth diode D5 will be turned on to provide a freewheeling path, the switching state thereof needs to be updated to "on state", and the state of the sixth diode D6 needs to be updated to "off state".
Similarly, referring to fig. 9, fig. 9a is a schematic diagram before state change, and fig. 9b is a schematic diagram after state change, assuming that the switch state of the fourth switch set S4 at the previous time step is "third state", the bridge arm current ihb<0. If it is detected at the current time step that the switching state thereof is changed to the "first state", and the state of the third switch group S3 is the "third state". The sixth diode D6 will be turned on and its switching state is updated to the "on state" and the state of the fifth diode D5 is updated to the "off state".
Further, the step of S108 further includes:
when the second switch group is in a non-third state in the previous time step, the initial state is a third state, and the bridge arm current is greater than 0:
when the initial state of the first switch group is a third state and the sum of the voltages of the first capacitor and the second capacitor is greater than 0, updating the state of the third switch group to the first state, and updating the state of the fourth switch group to the first state;
when the initial state of the first switch group is a non-third state and the voltage of the second capacitor is greater than 0, the state of the third switch group is updated to a second state, the state of the fourth switch group is updated to a first state, and the fifth diode is updated to a conducting state;
when the third switch group is in a non-third state in the last time step, the initial state is a third state, and the bridge arm current is less than 0:
when the initial state of the fourth switch group is the third state and the sum of the voltages of the first capacitor and the second capacitor is greater than 0, the state of the first switch group is updated to the first state, and the state of the second switch group is also updated to the first state;
when the initial state of the fourth switch group is a non-third state and the voltage of the first capacitor is greater than 0, the state of the first switch group is updated to a second state, the state of the second switch group is updated to a first state, and the sixth diode is updated to a conducting state.
When the initial state of the first switch group is a non-first state and the voltage of the first capacitor is greater than 0, the state of the fifth diode is updated to be a turn-off state;
when the initial state of the fourth switch group is not the first state and the voltage of the second capacitor is greater than 0, the state of the sixth diode is updated to be the off state.
This step is diode forced turn off, similar to the diode forced freewheel described above.
Referring to fig. 10, fig. 10a is a schematic diagram before state change, fig. 10b is a schematic diagram after state change, the second switch set S2 determines on/off of the entire upper arm, and it is assumed that the state of the second switch set S2 is not the third state, i.e., "the first state" or "the second state" at the previous time step, and the arm current i ishbIs positive. At this time, the states of the first switch group S1, the fifth diode S5 and the sixth diode S6 may be any states, and the states of the third switch group S3 and the fourth switch group S4 are "the second state", the leg current is routed through a third diode D3 and a fourth diode D4. If the state change of the second switch group S2 to the "third state" is detected at the current time step and the state of the first switch group S1 is the "third state", the sum of the voltages of the first capacitor C1 and the second capacitor C2 is greater than 0. It can be determined that the current paths of the arm currents are the first switch tube T1 and the second switch tube T2, and the lower arm will directly bear the voltages of the capacitors C1 and C2 with the conduction of T2, and D3 and D4 will be directly turned off.
In addition, referring to fig. 11, fig. 11a is a schematic diagram before the state change, fig. 11b is a schematic diagram after the state change, if it is detected that the second switch group S2 changes to the "third state" at the current time step, the state of the first switch group S1 is not the "third state", and the voltage of the second capacitor C2 is greater than 0. It can be determined that the bridge arm current needs to flow through the fifth diode D5 and the second switching tube T2, the switching state of the fifth diode D5 needs to be updated to the "on state", the lower bridge arm is subjected to the voltage of the capacitor C2, the third diode D3 and the fourth diode D4 are subjected to the inverse voltage and turned off, and the switching states of the third switch group S3 and the fourth switch group S4 need to be updated to the "first state".
Similarly, referring to fig. 12, fig. 12a is a schematic diagram before the state change, and fig. 12b is a schematic diagram after the state change, assuming that the switch state of the third switch set S3 is not the "third state" in the previous time step, and the bridge arm current ihbIs negative. If the state of the third switch set S3 changes to the "third state" at the current time step, the state of the fourth switch set S4 is the "third state" and the sum of the voltages of the first capacitor C1 and the second capacitor C2 is positive, the states of S1 and S2 are updated to the "first state". Referring to fig. 13, fig. 13a is a schematic diagram before state change, fig. 13b is a schematic diagram after state change, if the state of the third switch set S3 is changed to the "third state", the state of the fourth switch set S4 is not the "third state" and the voltage of the first capacitor C1 is positive at the current time step, at this time, the states of S1 and S2 need to be updated to the "first state", and the state of the switch S6 needs to be updated to the "second state". A
Meanwhile, the forced turn-off of the diodes is also embodied in the turn-off process of the fifth diode D5 and the sixth diode D6. As can be seen from the circuit diagram of the NPC converter, as long as the state of the first switch group S1 is not the "first state" and the voltage of the first capacitor C1 is positive, the fifth diode D5 is inevitably turned off due to the reverse voltage. Similarly, as long as the state of the fourth switch group S4 is not the "first state" and the voltage of the second capacitor C2 is positive, the sixth diode D6 is inevitably turned off by being subjected to the reverse voltage.
According to the above implementation manner, the states of the switch group and the independent diode in the current time step can be updated, and it should be noted that when the states of the switch group or the independent diode do not need to be updated, the initial state of the switch group or the independent diode is taken as the state of the current time step.
After the initial state and the state updating step, the process is further executed continuously and circularly until the preset time step is reached, for example, if the number of the preset time steps is 200, the state of 200 time steps needs to be determined.
Optionally, S112 includes:
and determining the resistance values of the switch group and the independent diodes corresponding to all time steps according to the states, and forming an admittance matrix.
And performing electromagnetic transient simulation according to the admittance matrix.
Namely, after the states of the switch group and the independent diodes in all time steps are determined, the corresponding resistance values can be determined, and then an admittance matrix is formed and simulation is carried out.
On the basis of the foregoing implementation manner, please refer to fig. 14, an embodiment of the present application further provides a converter electromagnetic transient simulation apparatus 300, where the converter electromagnetic transient simulation apparatus 300 includes:
and a norton equivalent unit 310, configured to perform norton equivalent on devices in a converter, where the converter includes a switch group and an independent diode, and the switch group includes a switch tube and a combined diode.
It is understood that S102 may be performed by the norton equivalent unit 310.
The parameter obtaining unit 320 is configured to obtain states, driving signals, terminal voltages, branch currents, and bridge arm currents of the equivalent switch group and the equivalent independent diode in the previous time step.
It is understood that S104 may be performed by the parameter acquiring unit 320.
The state determining unit 330 is configured to determine initial states of the switch set and the independent diode at a current time step according to the state, the driving signal, the terminal voltage, and the branch current at the previous time step.
It is understood that S106 may be performed by the state determination unit 330.
And the state updating unit 340 is configured to update the states of the switch group and the independent diode according to the state in the previous time step, the initial state and the bridge arm current, and use the updated states as the states of the switch group and the independent diode in the current time step.
It is to be appreciated that 108 can be performed by the status update unit 340.
The state determining unit 330 and the state updating unit 340 are further configured to repeatedly perform the preliminary determination and the state updating until a predetermined time step is reached.
The simulation unit 350 is configured to perform electromagnetic transient simulation according to states of the switch group and the independent diodes at all time steps.
It is understood that 112 may be performed by the simulation unit 350.
Naturally, each step in the above implementation manner has a corresponding functional module, and since the above embodiment has been described in detail, no further description is provided herein.
In summary, the present application provides a method and an apparatus for electromagnetic transient simulation of a converter, an electronic device and a storage medium, wherein norton equivalence is performed on devices in the converter, wherein the converter includes a switch group and an independent diode, and the switch group includes a switch tube and a combined diode; then obtaining the state, the driving signal, the terminal voltage, the branch current and the bridge arm current of the equivalent switch group and the equivalent independent diode in the last time step; determining the initial state of the switch group and the independent diode in the current time step according to the state, the driving signal, the terminal voltage and the branch current in the previous time step; updating the states of the switch group and the independent diode according to the state and the initial state in the previous time step and the bridge arm current, and taking the updated states as the states of the switch group and the independent diode in the current time step; then, the process of the preliminary judgment and the state updating is repeatedly executed until a preset time step is reached; and finally, performing electromagnetic transient simulation according to the states of the switch group and the independent diodes in all time steps. Because the stable switch state is directly determined at the current time step, the iterative process of solving the stable switch state in the traditional electromagnetic transient simulation is eliminated, the simulation precision equivalent to that of the traditional detailed model can be ensured, the simulation time consumption is remarkably reduced, and the simulation efficiency is higher.
In the embodiments provided in the present application, it should be understood that the disclosed apparatus and method may be implemented in other ways. The apparatus embodiments described above are merely illustrative and, for example, the flowchart and block diagrams in the figures illustrate the architecture, functionality, and operation of possible implementations of apparatus, methods and computer program products according to embodiments of the present application. In this regard, each block in the flowchart or block diagrams may represent a module, segment, or portion of code, which comprises one or more executable instructions for implementing the specified logical function(s).
It should also be noted that, in some alternative implementations, the functions noted in the block may occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved.
It will also be noted that each block of the block diagrams and/or flowchart illustration, and combinations of blocks in the block diagrams and/or flowchart illustration, can be implemented by special purpose hardware-based systems which perform the specified functions or acts, or combinations of special purpose hardware and computer instructions.
In addition, the functional modules in the embodiments of the present application may be integrated together to form an independent part, or each module may exist separately, or two or more modules may be integrated to form an independent part.
The functions, if implemented in the form of software functional modules and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present application or portions thereof that substantially contribute to the prior art may be embodied in the form of a software product stored in a storage medium and including instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method according to the embodiments of the present application. And the aforementioned storage medium includes: u disk, removable hard disk, read only memory, random access memory, magnetic or optical disk, etc. for storing program codes.
Although the present invention is disclosed above, the present invention is not limited thereto. Various changes and modifications may be effected therein by one skilled in the art without departing from the spirit and scope of the invention as defined in the appended claims.
Claims (10)
1. A converter electromagnetic transient simulation method is characterized by comprising the following steps:
performing Norton equivalence on devices in the converter, wherein the converter comprises a switch group and an independent diode, and the switch group comprises a switch tube and a combined diode;
obtaining the state, the driving signal, the terminal voltage, the branch current and the bridge arm current of the equivalent switch group and the equivalent independent diode in the previous time step;
determining the initial state of the switch group and the independent diode in the current time step according to the state, the driving signal, the terminal voltage and the branch current in the previous time step;
updating the states of the switch group and the independent diode according to the state in the previous time step, the initial state and the bridge arm current, and taking the updated states as the states of the switch group and the independent diode in the current time step;
the process of preliminary judgment and state updating is repeatedly executed until a preset time step is reached;
and performing electromagnetic transient simulation according to the states of the switch group and the independent diode at all time steps.
2. The converter electromagnetic transient simulation method of claim 1, wherein said switch bank comprises a first state, a second state and a third state, wherein when said switch bank is in said first state, said switch tube is closed, and said combining diode is closed; when the switch group is in a second state, the switch tube is closed, and the combined diode is conducted; when the switch group is in a third state, the switch tube is conducted, and the combined diode is closed; the step of determining the initial state of the switch group and the independent diode at the current time step according to the state, the driving signal, the terminal voltage and the branch current in the previous time step comprises the following steps:
when the switch group is in a third state in the last time step and the branch current is less than 0, determining that the initial state of the switch group in the current time step is a second state;
when the switch group is in a third state in the last time step, the branch current is greater than 0 and the driving signal is 0, determining that the initial state of the switch group in the current time step is a first state;
when the switch group is in the second state in the last time step, the branch current is greater than 0 and the driving signal is 1, determining that the initial state of the switch group in the current time step is the third state;
when the switch group is in the second state in the last time step, the branch current is greater than 0 and the driving signal is 0, determining that the initial state of the switch group in the current time step is the first state;
when the switch group is in a first state in the last time step, the terminal voltage is greater than 0 and the driving signal is 1, determining that the initial state of the switch group in the current time step is a third state;
and when the switch group is in a first state in the last time step and the terminal voltage is less than 0, determining that the initial state of the switch group in the current time step is a second state.
3. The converter electromagnetic transient simulation method of claim 1, wherein said individual diodes comprise an off state and an on state, and said step of determining initial states of said switch set and individual diodes at a current time step based on said state at said previous time step, said drive signal, said terminal voltage and said branch current comprises:
when the independent diode is in a conducting state in the last time step and the branch current is less than 0, determining that the initial state of the independent diode in the current time step is a closing state;
and when the independent diode is in a closed state in the previous time step and the branch current is greater than 0, preliminarily judging that the independent diode is in a conducting state in the current time step.
4. The electromagnetic transient simulation method of the converter according to claim 1, wherein the converter comprises an upper bridge arm set and a lower bridge arm set, the upper bridge arm set and the lower bridge arm set are symmetrically arranged, the upper bridge arm set comprises a first switch set, a second switch set and a fifth diode, and the lower bridge arm set comprises a third switch set, a fourth switch set and a sixth diode; the switch group comprises a first state, a second state and a third state, when the switch group is in the first state, the switch tube is closed, and the combined diode is closed; when the switch group is in a second state, the switch tube is closed, and the combined diode is conducted; when the switch group is in a third state, the switch tube is conducted, and the combined diode is closed; the independent diode comprises an off state and an on state; the step of updating the states of the switch group and the independent diode according to the state in the previous time step, the initial state and the bridge arm current, and taking the updated states as the states of the switch group and the independent diode in the current time step comprises the following steps:
when the first switch group is in a third state, the initial state is a first state and the bridge arm current is greater than 0 in the previous time step, the state of the fifth diode is updated to be a conducting state, and the state of the sixth diode is updated to be a switching-off state;
when the second switch group is in a third state, the initial state is a first state and the bridge arm current is greater than 0 in the previous time step, the state of the third switch group is updated to a second state, the state of the fourth switch group is updated to a second state, and the state of the fifth diode is updated to a turn-off state;
when the fourth switch group is in the third state, the initial state is the first state and the bridge arm current is less than 0 in the previous time step, the state of the fifth diode is updated to be the off state, and the state of the sixth diode is updated to be the on state;
when the third switch group is in the third state, the initial state is the first state, and the bridge arm current is less than 0 in the previous time step, the state of the first switch group is updated to the second state, the state of the second switch group is updated to the second state, and the state of the sixth diode is updated to the off state.
5. The electromagnetic transient simulation method of the converter according to claim 1, wherein the converter comprises an upper bridge arm set and a lower bridge arm set, the upper bridge arm set and the lower bridge arm set are symmetrically arranged, the upper bridge arm set comprises a first switch set, a second switch set, a fifth diode and a first capacitor, the lower bridge arm set comprises a third switch set, a fourth switch set, a sixth diode and a second capacitor; the switch group comprises a first state, a second state and a third state, when the switch group is in the first state, the switch tube is closed, and the combined diode is closed; when the switch group is in a second state, the switch tube is closed, and the combined diode is conducted; when the switch group is in a third state, the switch tube is conducted, and the combined diode is closed; the independent diode comprises an off state and an on state; the step of updating the states of the switch group and the independent diode according to the state in the previous time step, the initial state and the bridge arm current, and taking the updated states as the states of the switch group and the independent diode in the current time step comprises the following steps:
when the second switch group is in a non-third state in the last time step, the initial state is a third state, and the bridge arm current is greater than 0:
when the initial state of the first switch group is a third state and the sum of the voltages of the first capacitor and the second capacitor is greater than 0, updating the state of the third switch group to the first state, and updating the state of the fourth switch group to the first state;
when the initial state of the first switch group is a non-third state and the voltage of the second capacitor is greater than 0, the state of the third switch group is updated to a second state, the state of the fourth switch group is updated to a first state, and the fifth diode is updated to a conducting state;
when the third switch group is in a non-third state in the last time step, the initial state is a third state, and the bridge arm current is less than 0:
when the initial state of the fourth switch group is a third state and the sum of the voltages of the first capacitor and the second capacitor is greater than 0, updating the state of the first switch group to be a first state, and updating the state of the second switch group to be a first state;
when the initial state of the fourth switch group is a non-third state and the voltage of the first capacitor is greater than 0, the state of the first switch group is updated to a second state, the state of the second switch group is updated to a first state, and the sixth diode is updated to a conducting state.
6. The electromagnetic transient simulation method of the converter according to claim 1, wherein the converter comprises an upper bridge arm set and a lower bridge arm set, the upper bridge arm set and the lower bridge arm set are symmetrically arranged, the upper bridge arm set comprises a first switch set, a second switch set, a fifth diode and a first capacitor, the lower bridge arm set comprises a third switch set, a fourth switch set, a sixth diode and a second capacitor; the switch group comprises a first state, a second state and a third state, when the switch group is in the first state, the switch tube is closed, and the combined diode is closed; when the switch group is in a second state, the switch tube is closed, and the combined diode is conducted; when the switch group is in a third state, the switch tube is conducted, and the combined diode is closed; the independent diode comprises an off state and an on state; the step of updating the states of the switch group and the independent diode according to the state in the previous time step, the initial state and the bridge arm current, and taking the updated states as the states of the switch group and the independent diode in the current time step comprises the following steps:
when the initial state of the first switch group is a non-first state and the voltage of the first capacitor is greater than 0, the state of the fifth diode is updated to be an off state;
when the initial state of the fourth switch group is a non-first state and the voltage of the second capacitor is greater than 0, the state of the sixth diode is updated to be an off state.
7. The converter electromagnetic transient simulation method of claim 1, wherein said step of performing electromagnetic transient simulation based on the state of said switch bank and said individual diodes at all time steps comprises:
determining resistance values of the switch group and the independent diodes corresponding to all time steps according to the state, and forming an admittance matrix;
and performing electromagnetic transient simulation according to the admittance matrix.
8. A converter electromagnetic transient simulation apparatus, the apparatus comprising:
the converter comprises a converter, a Norton equivalent unit, a converter control unit and a control unit, wherein the Norton equivalent unit is used for carrying out Norton equivalence on devices in the converter, the converter comprises a switch group and an independent diode, and the switch group comprises a switch tube and a combined diode;
the parameter acquisition unit is used for acquiring the state, the driving signal, the terminal voltage, the branch current and the bridge arm current of the equivalent switch group and the equivalent independent diode in the previous time step;
the state determining unit is used for determining the initial state of the switch group and the independent diode in the current time step according to the state, the driving signal, the terminal voltage and the branch current in the previous time step;
the state updating unit is used for updating the states of the switch group and the independent diode according to the state in the previous time step, the initial state and the bridge arm current, and taking the updated states as the states of the switch group and the independent diode in the current time step;
the state determining unit and the state updating unit are also used for repeatedly executing the processes of preliminary judgment and state updating until a preset time step is reached;
and the simulation unit is used for performing electromagnetic transient simulation according to the states of the switch group and the independent diode in all time steps.
9. An electronic device, comprising:
a memory for storing one or more programs;
a processor;
the one or more programs, when executed by the processor, implement the method of any of claims 1-7.
10. A computer-readable storage medium, on which a computer program is stored which, when being executed by a processor, carries out the method according to any one of claims 1-7.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117556641A (en) * | 2024-01-11 | 2024-02-13 | 四川大学 | Constant equivalent conductivity electromagnetic transient modeling method based on Boost-full-bridge converter decoupling |
| CN117556641B (en) * | 2024-01-11 | 2024-03-26 | 四川大学 | Constant equivalent conductivity electromagnetic transient modeling method based on Boost-full-bridge converter decoupling |
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