阅读说明：本技术 一种交直流电力系统电磁暂态仿真装置 (Electromagnetic transient simulation device for alternating current and direct current power system ) 是由 翟鹤峰 赵利刚 洪潮 王长香 周挺辉 甄鸿越 黄冠标 吴小珊 徐原 于 2020-04-27 设计创作，主要内容包括：本发明公开了一种交直流电力系统电磁暂态仿真装置,包括：大步长仿真系统、小步长仿真系统、快速数据交互模块及连接模块；大步长仿真系统,用于采用预设的电磁暂态仿真模型,按照第一仿真步长对交流仿真系统进行仿真；小步长仿真系统,用于采用预先建立的FPGA高频仿真模型,按照第二仿真步长对由高频电力电子开关器件组成的直流系统进行仿真；连接模块,用于连接直流系统与交流系统；连接模块为变压器或传输线接口模型；快速数据交互模块,与大步长仿真系统、小步长仿真系统连接,用于对大步长仿真系统与小步长仿真系统进行仿真数据交互,能有效提升交直流大电网电磁暂态仿真的速度,同时适应大规模电力系统的快速仿真需求和精度需求。(The invention discloses an electromagnetic transient simulation device of an alternating current and direct current power system, which comprises: the system comprises a large-step-size simulation system, a small-step-size simulation system, a rapid data interaction module and a connection module; the large-step simulation system is used for simulating the alternating current simulation system according to a first simulation step length by adopting a preset electromagnetic transient simulation model; the small-step-size simulation system is used for simulating a direct-current system consisting of high-frequency power electronic switching devices according to a second simulation step size by adopting a pre-established FPGA high-frequency simulation model; the connecting module is used for connecting the direct current system and the alternating current system; the connecting module is a transformer or transmission line interface model; the rapid data interaction module is connected with the large-step-size simulation system and the small-step-size simulation system, is used for carrying out simulation data interaction on the large-step-size simulation system and the small-step-size simulation system, can effectively improve the speed of electromagnetic transient simulation of the AC/DC large power grid, and is suitable for the rapid simulation requirement and the precision requirement of the large-scale power system.)

1. An electromagnetic transient simulation apparatus for an ac/dc power system, the apparatus comprising: the system comprises a large-step-size simulation system, a small-step-size simulation system, a rapid data interaction module and a connection module;

the large-step simulation system is used for simulating the alternating current simulation system according to a first simulation step length by adopting a preset electromagnetic transient simulation model;

the small-step-size simulation system is used for simulating a direct-current system consisting of high-frequency power electronic switching devices according to a second simulation step size by adopting a pre-established FPGA high-frequency simulation model; wherein the first simulation step size is larger than the second simulation step size;

the connecting module is connected with the large-step-size simulation system and the small-step-size simulation system and is used for connecting the direct current system and the alternating current system; the connecting module is a transformer or transmission line interface model;

the rapid data interaction module is connected with the large-step-size simulation system and the small-step-size simulation system, and is used for performing simulation data interaction on the large-step-size simulation system and the small-step-size simulation system.

2. The device for electromagnetic transient simulation of a ac/dc power system of claim 1, further comprising a first external connection module, a second external connection module, and an external control and protection module;

the external control and protection module is connected with the large-step simulation system and the first external connection module and is used for protecting and controlling elements in the alternating current system; the second external connection module is connected with the small-step simulation system and the second external connection module and is used for protecting and controlling elements in the direct current system;

the first external connection module comprises a first IO interface and a first digital-to-analog conversion module; the first IO interface is connected with the first digital-to-analog conversion module, and the first IO interface is bidirectionally connected with the large-step simulation system;

the second external connection module comprises a second IO interface and a second digital-to-analog conversion module; the second IO interface is connected with the second digital-to-analog conversion module, and the second IO interface is bidirectionally connected with the small-step-size simulation system;

the external control and protection module comprises a first analog-to-digital conversion module, a second analog-to-digital conversion module and an external control and protection device; the external control and protection device is connected with the first analog-to-digital conversion module and the second analog-to-digital conversion module; the first analog-to-digital conversion module is connected with the first digital-to-analog conversion module, and the second analog-to-digital conversion module is connected with the second digital-to-analog conversion module.

3. The electromagnetic transient simulation device of the ac-dc power system of claim 1, wherein said fast data interaction module comprises an FPGA-based fast data interaction interface, a first communication interface, and a second communication interface;

the FPGA-based rapid data interaction interface is connected with the first communication interface and the second communication interface; the large-step simulation system is connected with the first communication interface, and the small-step simulation system is connected with the second communication interface.

4. The electromagnetic transient simulation device of any one of claims 1 to 3, wherein the external control and protection module is connected to the first external connection module and the second external connection module via optical fibers;

the large-step simulation system is connected with the first external connection module and the rapid data interaction module through optical fibers;

the small-step simulation system is connected with the second external connection module and the rapid data interaction module through optical fibers.

5. The electromagnetic transient simulation device of the ac-dc power system of claim 1, wherein said small step size simulation system is further configured to perform simulation modeling on said high-frequency power electronic switching device by using a preset L/C switching model to obtain a power electronic switching model; wherein the power electronic switch model satisfies the following relationship:

dt is the second simulation step length, L_sIs an equivalent inductance when the switch is closed, C_sIs an equivalent capacitance when the switch is turned off, R_sIs a resistance.

6. The electromagnetic transient simulation device of an ac-dc power system of claim 1, wherein said fast data interaction module is further configured to perform simulation data interaction on said large-step simulation system and said small-step simulation system in a preset asynchronous interaction manner; and the first simulation step length is integral multiple of the second simulation step length.

7. The electromagnetic transient simulation device of ac/dc power system of claim 3, wherein said FPGA-based fast data interaction interface is an FPGA development board supporting a pluggable optoelectronic transceiver interface.

Technical Field

The invention relates to the technical field of power system simulation, in particular to an electromagnetic transient simulation device for an alternating current and direct current power system.

Background

With the interconnection of regional power grids, modern power systems are continuously expanded in scale, and high-power electronic equipment such as high-voltage direct current transmission and FACTS (alternating current transmission systems) are widely applied to the power systems, so that the power systems are increasingly complex in component composition, dynamic characteristics of different time scales are interwoven, and new challenges are provided for electromagnetic transient simulation technologies of the power systems.

Although the electromagnetic transient simulation method has very high simulation accuracy, the simulation scale and the simulation speed are greatly limited because the electromagnetic transient simulation method is based on the calculation principle of three-phase transient. In order to increase the calculation speed of the electromagnetic transient calculation method, the existing research is mainly based on two methods. Firstly, a large-scale alternating current-direct current power grid is divided into a plurality of systems with smaller scales by utilizing a parallel computing technology, then simulation computation is respectively carried out, and information interaction is carried out at each step length. The other method is based on a large amount of computing hardware, and the computing speed of electromagnetic transient computing is improved through close cooperation between a computing program and bottom hardware, and the commonly used RTDS adopts the method to improve the computing speed.

The above method is in the category of fully custom integrated circuits, which have the characteristics of a serial processor. On one hand, the number of processors which can be carried by the simulation device is limited after all, and the unlimited increase is impossible; on the other hand, the mutual communication among a large number of parallel processors can become a bottleneck of the simulation speed. The Field Programmable Gate Array (FPGA) has high parallelism and pipeline processing capacity, can realize ultra-high speed numerical operation, can perform data interaction between different FPGA development boards through a high-speed communication means, and can well meet the rapid simulation requirement of a modern large-scale power system.

Disclosure of Invention

The embodiment of the invention provides an electromagnetic transient simulation device for an alternating current and direct current power system, which is used for realizing joint simulation based on an FPGA hardware simulation model and an electromagnetic transient software simulation model, effectively improving the electromagnetic transient simulation speed of an alternating current and direct current large power grid and simultaneously meeting the rapid simulation requirement and the precision requirement of the large power system.

An embodiment of the present invention provides an electromagnetic transient simulation apparatus for an ac/dc power system, the apparatus including: the system comprises a large-step-size simulation system, a small-step-size simulation system, a rapid data interaction module and a connection module;

the large-step simulation system is used for simulating the alternating current simulation system according to a first simulation step length by adopting a preset electromagnetic transient simulation model;

the small-step-size simulation system is used for simulating a direct-current system consisting of high-frequency power electronic switching devices according to a second simulation step size by adopting a pre-established FPGA high-frequency simulation model; wherein the first simulation step size is larger than the second simulation step size;

the connecting module is connected with the large-step-size simulation system and the small-step-size simulation system and is used for connecting the direct current system and the alternating current system; the connecting module is a transformer or transmission line interface model;

the rapid data interaction module is connected with the large-step-size simulation system and the small-step-size simulation system, and is used for performing simulation data interaction on the large-step-size simulation system and the small-step-size simulation system.

As an improvement of the above scheme, the device further comprises a first external connection module, a second external connection module and an external control and protection module;

the external control and protection module is connected with the large-step simulation system and the first external connection module and is used for protecting and controlling elements in the alternating current system; the second external connection module is connected with the small-step simulation system and the second external connection module and is used for protecting and controlling elements in the direct current system;

the first external connection module comprises a first IO interface and a first digital-to-analog conversion module; the first IO interface is connected with the first digital-to-analog conversion module, and the first IO interface is bidirectionally connected with the large-step simulation system;

the second external connection module comprises a second IO interface and a second digital-to-analog conversion module; the second IO interface is connected with the second digital-to-analog conversion module, and the second IO interface is bidirectionally connected with the small-step-size simulation system;

the external control and protection module comprises a first analog-to-digital conversion module, a second analog-to-digital conversion module and an external control and protection device; the external control and protection device is connected with the first analog-to-digital conversion module and the second analog-to-digital conversion module; the first analog-to-digital conversion module is connected with the first digital-to-analog conversion module, and the second analog-to-digital conversion module is connected with the second digital-to-analog conversion module.

As an improvement of the above scheme, the fast data interaction module comprises a fast data interaction interface based on the FPGA, a first communication interface and a second communication interface;

the FPGA-based rapid data interaction interface is connected with the first communication interface and the second communication interface; the large-step simulation system is connected with the first communication interface, and the small-step simulation system is connected with the second communication interface.

As an improvement of the above scheme, the external control and protection module is connected with the first external connection module and the second external connection module through optical fibers;

the large-step simulation system is connected with the first external connection module and the rapid data interaction module through optical fibers;

the small-step simulation system is connected with the second external connection module and the rapid data interaction module through optical fibers.

As an improvement of the above scheme, the small-step simulation system is further configured to perform simulation modeling on the high-frequency power electronic switching device by using a preset L/C switching model to obtain a switching model; wherein the switch model satisfies the following relationship:

dt is the second simulation step length, L_sIs an equivalent inductance when the switch is closed, C_sIs an equivalent capacitance when the switch is turned off, R_sIs a resistance.

As an improvement of the above scheme, the fast data interaction module is further configured to perform simulation data interaction on the large-step simulation system and the small-step simulation system in a preset asynchronous interaction manner; and the first simulation step length is integral multiple of the second simulation step length.

As an improvement of the above scheme, the FPGA-based fast data interaction interface is an FPGA development board supporting a pluggable photoelectric transceiving interface.

Compared with the prior art, the electromagnetic transient simulation device for the alternating current and direct current power system disclosed by the embodiment of the invention has the following beneficial effects:

the electromagnetic transient simulation device of the alternating current and direct current power system comprises a large-step-size simulation system, a small-step-size simulation system, a rapid data interaction module and a connection module; by setting the large-step-size simulation system, a preset electromagnetic transient simulation model is adopted, and the alternating current simulation system is simulated according to the first simulation step size, so that the calculation precision is ensured, and the calculation speed is greatly improved; by setting the small-step-size simulation system, simulating a direct-current system consisting of high-frequency power electronic switching devices according to a second simulation step size by adopting a pre-established FPGA high-frequency simulation model, wherein the first simulation step size is larger than the second simulation step size, and realizing rapid real-time simulation; the connecting module is connected with the large-step-size simulation system and the small-step-size simulation system and is used for connecting the direct current system and the alternating current system, wherein the connecting module is a transformer or transmission line interface model and plays a role in connecting the large-step-size simulation system and the small-step-size simulation system and realizing parallel calculation between the fast system and the slow system by utilizing the natural delay characteristic of the transmission line model; the rapid data interaction module is connected with the large-step-size simulation system and the small-step-size simulation system, so that the large-step-size simulation system and the small-step-size simulation system can perform simulation data interaction, the requirement of rapid data interaction is met, and the requirement of data delay is met. Therefore, by utilizing the parallel computing characteristic of the FPGA and adopting different simulation step lengths for different switching frequency parts of the AC/DC power system to simulate, the joint simulation based on the FPGA hardware simulation model and the electromagnetic transient software simulation model is realized, the electromagnetic transient simulation speed of the AC/DC power grid can be effectively improved, the quick simulation requirement and the precision requirement of a large-scale power system are met, the simulation scale and the quick simulation capability of the simulation system are greatly improved, and the cross-platform joint simulation can be realized.

Drawings

Fig. 1 is a schematic structural diagram of an electromagnetic transient simulation apparatus for an ac/dc power system according to an embodiment of the present invention;

fig. 2 is a schematic diagram of an equivalent circuit of an interface between an ac system and a dc system according to an embodiment of the present invention;

FIG. 3 is an internal schematic diagram of a communication interface provided by an embodiment of the present invention;

fig. 4 is an equivalent circuit diagram of a high-frequency power electronic switching device in small step simulation according to an embodiment of the present invention;

FIG. 5 is a schematic diagram of a hardware implementation of an FPGA-based power electronic switch model according to an embodiment of the present invention;

FIG. 6 is a diagram illustrating a small step simulation system architecture according to an embodiment of the present invention;

fig. 7 is a schematic diagram of a data interaction manner between a large-step simulation system and a small-step simulation system according to an embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. 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 invention.

Referring to fig. 1, a schematic structural diagram of an electromagnetic transient simulation apparatus for an ac/dc power system according to an embodiment of the present invention is shown, including: a large-step simulation system 11, a small-step simulation system 12, a fast data interaction module 13 and a connection module 14;

the large-step simulation system 11 is configured to simulate the alternating current simulation system according to a first simulation step by using a preset electromagnetic transient simulation model;

the small-step-size simulation system 12 is used for simulating a direct-current system composed of high-frequency power electronic switching devices according to a second simulation step size by adopting a pre-established FPGA high-frequency simulation model; wherein the first simulation step size is larger than the second simulation step size;

the connection module 14 is connected to the large-step simulation system 11 and the small-step simulation system 12, and is configured to connect the dc system and the ac system; the connection module 13 is a transformer or transmission line interface model;

the fast data interaction module 13 is connected to the large-step simulation system 11 and the small-step simulation system 12, and is configured to perform simulation data interaction on the large-step simulation system 11 and the small-step simulation system 12.

It should be noted that the small-step simulation system 12 stores an FPGA electromagnetic transient simulation program, and specifically performs small-step simulation on a dc system of a VSC-HVDC or other power electronic device including a high switching frequency by using an FPGA high-frequency hardware simulation model. The large-step-length simulation system 11 stores a conventional electromagnetic transient simulation program, and specifically performs large-step-length simulation on other low-frequency elements such as an alternating-current system and a direct-current line by using an electromagnetic transient software simulation model. Preferably, the small-step simulation system 12 simulates a direct current system composed of high-frequency switching circuits such as an MMC converter valve in a second simulation step of less than 5 microseconds, and the large-step simulation system 11 simulates an alternating current system in a first simulation step of more than 50 microseconds.

In this embodiment, the ac system and the dc system in the two simulation systems are connected by a transmission line interface model or a transformer. Referring to fig. 2, which is a schematic diagram of an equivalent circuit of an interface between an ac system and a dc system according to an embodiment of the present invention, the dc system is equivalent to a current source in large-step simulation of the ac system, and the ac system is equivalent to a voltage source in small-step simulation of the dc system. Preferably, for the transformer or the transmission line interface model, a Bailon transmission line model or a decoupling transformer and the like can be adopted for realization, and the function of connecting two simulation systems with large and small step lengths or realizing parallel calculation between a fast system and a slow system by utilizing the natural delay characteristic of the transmission line model is realized.

In a preferred embodiment, the device further comprises a first external connection module 15, a second external connection module 16 and an external control and protection module 17;

the external control and protection module 17 is connected to the large-step simulation system 11 and the first external connection module 15, and is configured to protect and control elements in the ac system; the second external connection module 16 is connected to the small-step simulation system 12 and the second external connection module, and is configured to protect and control elements in the dc system;

the first external connection module 15 includes a first IO interface 151 and a first digital-to-analog conversion module 152; the first IO interface 151 is connected to the first digital-to-analog conversion module 152, and the first IO interface 151 is bidirectionally connected to the large-step simulation system 11;

the second external connection module 16 includes a second IO interface 161 and a second digital-to-analog conversion module 162; the second IO interface 161 is connected to the second digital-to-analog conversion module 162, and the second IO interface 161 is bidirectionally connected to the small-step simulation system 12;

the external control and protection module 17 includes a first analog-to-digital conversion module 171, a second analog-to-digital conversion module 172 and an external control and protection device 173; the external control and protection device 173 is connected to the first analog-to-digital conversion module 171 and the second analog-to-digital conversion module 172; the first analog-to-digital conversion module 171 is connected to the first digital-to-analog conversion module 152, and the second analog-to-digital conversion module 172 is connected to the second digital-to-analog conversion module 162.

In this embodiment, the external control and protection device 173 is specifically an external control protection system connected to the large-step simulation system 11 and the small-step simulation system 12, and is mainly used for protecting and controlling elements in the ac/dc simulation system and outputting control signals, such as trigger pulses and protection signals. The first IO interface 151, the second IO interface 161, the first digital-to-analog conversion module 152, the second digital-to-analog conversion module 162, the first analog-to-digital conversion module 171, and the second analog-to-digital conversion module 172 are used for realizing the joint simulation effect of the large-step-size simulation system 11 and the small-step-size simulation system 12 and the external control and protection device 173, realizing the mutual conversion between analog quantity and digital quantity through analog-to-digital conversion and digital-to-analog conversion, and transmitting the signal of the external control and protection device 173 to the large-step-size simulation system 11 and the small-step-size simulation system 12 for simulation. The embodiment can realize interactive simulation of an external actual physical device (such as a control protection system) and a simulation system, and provides certain convenience for verifying the function of the actual physical device.

Further, preferably, the external control and protection module 17 is connected to the first external connection module 15 and the second external connection module 16 by optical fibers; the large-step simulation system 11 is connected with the first external connection module 15 through an optical fiber; the small-step simulation system 12 is connected to the second external connection module 16 through an optical fiber. In order to improve the speed of electromagnetic transient simulation, all data interaction adopts optical fibers for transmission interaction.

In a preferred embodiment, the fast data interaction module 13 includes an FPGA-based fast data interaction interface 133, a first communication interface 131, and a second communication interface 132;

the FPGA-based fast data interaction interface 133 is connected to the first communication interface 131 and the second communication interface 132; the large-step simulation system 11 is connected to the first communication interface 131, and the small-step simulation system 12 is connected to the second communication interface 132.

Preferably, the FPGA-based fast data interaction interface 133 is an FPGA development board supporting a pluggable optoelectronic transceiver interface, and can support data interaction with other boards or external devices.

Further, preferably, the fast data interaction module 13 is connected to the large-step simulation system 11 and the small-step simulation system 12 through optical fibers. Specifically, the first communication interface 131 and the second communication interface 132 are connected to the large-step simulation system 11 and the small-step simulation system 12 by using optical fibers with high transmission rate and high transmission speed, and perform data communication by using an Aurora protocol of point-to-point high-speed serial transmission.

Further, the first communication interface 131 and the second communication interface 132 are preferably FPGA-based communication interfaces. Illustratively, referring to fig. 3, it is an internal schematic diagram of a communication interface according to an embodiment of the present invention, which includes an emulated communication data cache module 1, a data splicing module 2, a spliced data cache module 3, and a high-speed transceiver 4. The simulation communication data cache module 1 is realized by a double-rate RAM and is used for solving the matching problem of a sending data time domain and a splicing data clock domain; the data splicing module 2 is used for splitting the communication data into data with 16-bit or 8-bit data width supported by the high-speed transceiver 4; the splicing data cache module 3 is realized by FIFO (first input first output) and is used for solving the matching problem of a splicing data clock domain and a data transceiving clock domain; the high-speed transceiver 4 is used for receiving and transmitting the spliced communication data. Meanwhile, the main circuit of the FPGA and the IP core of the transceiver are driven by different clocks.

In a preferred embodiment, the small-step simulation system 12 is further configured to perform simulation modeling on the high-frequency power electronic switching device by using a preset L/C switching model to obtain a power electronic switching model.

In this embodiment, referring to fig. 4, an equivalent circuit diagram of a high-frequency power electronic switching device in small-step simulation provided by an embodiment of the present invention is provided, and in order to achieve the purpose of increasing the electromagnetic transient simulation speed, a behavior modeling method is adopted for the high-frequency power electronic switching device, that is, an L/C switching model is adopted (that is, as shown in fig. 4(a), a small inductor is used to simulate the switch closing, Ls represents the inductor when the switch is closed, and as shown in fig. 4(b), a small capacitor is used to simulate the switch opening, and Cs represents the capacitor when the switch is opened), so that admittance matrices in different converter operating states are the same, and the switching of the switch states is only related to history quantities, thereby avoiding storage pressure caused by matrix factorization calculation and a large number of inverse matrices, and greatly improving the calculation speed of simulation. In addition, in order to eliminate the influence of numerical value oscillation and energy oscillation as much as possible and ensure the numerical value stability, a series branch of a resistor Rs and a capacitor Cs is further used for simulating the opening of the switch, the oscillation caused by the sudden change of the switch state is damped by the resistor Rs, and an equivalent circuit of the opening and closing of the switch is shown in fig. 4 (b).

In order to meet the requirement that the admittance array of the system is unchanged when the switch is switched on and switched off, the resistance, the inductance and the capacitance in the power electronic switch model meet the following relations:

dt is the second simulation step length, L_sIs an equivalent inductance when the switch is closed, C_sIs an equivalent capacitance when the switch is turned off, R_sIs a resistance.

Further, the method can be used for preparing a novel materialIn a preferred embodiment, referring to fig. 5, a schematic diagram of a hardware implementation of the FPGA-based power electronic switch model according to an embodiment of the present invention is shown, where the parameter a is₁And A₂The value of (A) is determined by the switch state, and the RAM of the memory_v、RAM_iAnd RAM_histFor storing the switching voltage, the switching current and the history quantity. Wherein, the RAM_{A1_open}、RAM_{A1_closed}、RAM_{A2_open}、RAM_{A2_closed}For storing A when each switch is open or closed, respectively₁And the value A of A2_{1_open}、A_{1_closed}、A_{2_open}、A_{2_closed}，RAM_stateFor storing the switching state of each IGBT. Referring to fig. 4, the history solving step is as follows: at the beginning of the calculation at each time step, A_{1_open}、A_{1_closed}、A_{2_open}、A_{2_closed}And state is read out from the memory at the same time, wherein A_{1_open}、A_{1_closed}、A_{2_open}、A_{2_closed}Respectively passing through two data distributors, and judging the current step A by the on-off state₁And A₂And (4) correspondingly taking a value. At the same time, the switch terminal voltage v (t-delta t) and the switch current i (t-delta t) of the previous time step are read out with a delay of one clock, and the output result A of the data distributor₁、A₂Keeping data alignment, simultaneously performing multiplication operation through 2 floating-point number multipliers, and finally obtaining a history quantity I through a floating-point number adder_h(t-. DELTA.t) wherein I_h(t)＝A₁v(t-Δt)+A₂i (t- Δ t), then stored in RAM_histAnd (4) calculating the next time step. In the embodiment, a foundation is laid for the small-step-length rapid simulation of the power electronic equipment through high spatial parallelism and time parallelism.

In another preferred embodiment, referring to fig. 6, which is a schematic diagram of a small-step simulation system architecture provided in an embodiment of the present invention, for example, a calculation architecture of the small-step simulation system 12 is mainly divided into a non-real-time simulation portion located in a PC computer and a real-time simulation portion designed based on an FPGA, where the non-real-time portion needs to firstly use an offline electromagnetic transient program of the PC computer to perform example reading and topology recognition on a simulation example, and obtain calculation parameters of a relevant element. After the initial processing of the off-line program, text files for storing information such as node information, element calculation parameters, global calculation example parameters and the like are generated, further converted into HDL codes, initial data files of a memory, global parameter assignment files and the like, and sent to the integrated development environment of the PC. The engineering design in the integrated development environment is a real-time simulation system of the electric power system based on a hardware description language, an electric appliance system simulation platform of the electric system based on a node method and a control system simulation platform of the control system based on sequential solution carry out data interaction, a bit stream file can be generated after the real-time simulation system design is subjected to pin distribution, synthesis, layout and wiring, the bit stream file is downloaded to an FPGA chip on a hardware development board through a JTAG interface and a USB cable, and real-time simulation is started formally. Further, after the bit stream file is downloaded to the FPGA chip, the start and stop, the result output, the state reset and the like of the real-time simulation can be controlled through various set keys. The result of the simulation output can be transmitted back to the PC through a USB cable, an RS232 interface or other interfaces, and the result can also be converted into analog quantity through a D/A converter and displayed through an oscilloscope.

Preferably, the electromagnetic transient simulation program of the large-step simulation system may be any currently general or autonomously developed electromagnetic transient simulation program. Illustratively, the electromagnetic transient simulation program is an esp (electronic simulation program) program autonomously developed by the southern power grid science and research institute, and the program realizes the solution of the electromagnetic transient simulation program by using a node analysis method.

In a preferred embodiment, the fast data interaction module 13 is further configured to perform simulation data interaction on the large-step simulation system 11 and the small-step simulation system 12 in a preset asynchronous interaction manner; and the first simulation step length is integral multiple of the second simulation step length.

It should be noted that, referring to fig. 7, it is a schematic diagram of a data interaction manner between the large-step simulation system and the small-step simulation system provided in an embodiment of the present invention, where a simulation step of the large-step simulation system 11 is Δ T, a simulation step of the small-step simulation system 12 is Δ T, and Δ T is selected as an integer multiple of Δ T, and in a case of considering communication delay, the data interaction method can effectively reduce an influence of communication delay on simulation accuracy.

The embodiment of the invention provides an electromagnetic transient simulation device of an alternating current and direct current power system, which comprises a large-step-size simulation system, a small-step-size simulation system, a rapid data interaction module and a connection module; by setting the large-step-size simulation system, a preset electromagnetic transient simulation model is adopted, and the alternating current simulation system is simulated according to the first simulation step size, so that the calculation precision is ensured, and the calculation speed is greatly improved; by setting the small-step-size simulation system, simulating a direct-current system consisting of high-frequency power electronic switching devices according to a second simulation step size by adopting a pre-established FPGA high-frequency simulation model, wherein the first simulation step size is larger than the second simulation step size, and realizing rapid real-time simulation; the connecting module is connected with the large-step-size simulation system and the small-step-size simulation system and is used for connecting the direct current system and the alternating current system, wherein the connecting module is a transformer or transmission line interface model and plays a role in connecting the large-step-size simulation system and the small-step-size simulation system and realizing parallel calculation between the fast system and the slow system by utilizing the natural delay characteristic of the transmission line model; the rapid data interaction module is connected with the large-step-size simulation system and the small-step-size simulation system, so that the large-step-size simulation system and the small-step-size simulation system can perform simulation data interaction, the requirement of rapid data interaction is met, and the requirement of data delay is met. Therefore, by utilizing the parallel computing characteristic of the FPGA and adopting different simulation step lengths for different switching frequency parts of the AC/DC power system to simulate, the joint simulation based on the FPGA hardware simulation model and the electromagnetic transient software simulation model is realized, the electromagnetic transient simulation speed of the AC/DC power grid can be effectively improved, the quick simulation requirement and the precision requirement of a large-scale power system are met, the simulation scale and the quick simulation capability of the simulation system are greatly improved, and the cross-platform joint simulation can be realized.

While the foregoing is directed to the preferred embodiment of the present invention, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention.