Simulation Method and System for AC / DC Power System, Computer Equipment and Medium

Abstract

The present application relates to a simulation method, simulation system, device, and medium for an AC-DC power system. The method includes: decoupling the power grid to be simulated to obtain the AC power grid to be simulated and the DC power grid to be simulated; based on a first processor, using a preset electromagnetic transient simulation model to simulate the AC power grid to be simulated and determining the simulation result of the AC system; based on a second processor, using a preset logic gate array simulation model to simulate the DC power grid to be simulated and determining the simulation result of the DC system; based on the first processor, obtaining the simulation result of the DC system of the second processor, and determining the complete simulation result of the AC system of the power grid to be simulated according to the simulation results of the AC system and the DC system; based on the second processor, obtaining the simulation result of the AC system of the first processor, and determining the complete simulation result of the DC system of the power grid to be simulated according to the simulation results of the AC system and the DC system. Thus, while ensuring the simulation accuracy and precision, the simulation speed is improved.

Description

Technical Field

[0001] The present application relates to the technical field of power system simulation, and particularly to a simulation method, a simulation system, a computer device, and a computer-readable storage medium for an AC-DC power system. Background Art

[0002] With the development of power system technology, due to the interconnection of regional power grids, the scale of modern power systems has been continuously expanding. A large number of high-power power electronic equipment such as high-voltage direct current (HVDC) transmission and flexible AC transmission systems (FACTS) have been widely used in power systems, making the component composition of power systems increasingly complex. In order to analyze the dynamic characteristics of power systems, it is necessary to perform electromagnetic transient simulation on power systems, and the speed of electromagnetic transient simulation is crucial for analyzing power systems. Therefore, for a complex power system including an AC power grid and a DC power grid, how to make the speed of electromagnetic transient simulation faster is a problem that needs to be solved currently.

[0003] In traditional technologies, existing commercial real-time simulation platforms such as RTDS (real time digital simulation system), ARENE (management system simulation and simulation software), HYPERSIM (large-scale power system real-time digital simulation software), NETOMAC (power system simulation software), and RT-LAB (system real-time simulation platform software package) are used to perform electromagnetic transient simulation on power systems.

[0004] However, a power system includes a DC power grid and an AC power grid. Since the number of nodes in the DC power grid is large while the number of nodes in the AC power grid is small, in order to balance simulation accuracy and simulation speed, different simulation methods are required for the AC power grid and the DC power grid during simulation. However, traditional simulation platforms can only perform simulation on the entire power system using the same simulation method during power system simulation. Summary of the Invention

[0005] Based on this, in view of the above technical problems, it is necessary to provide a simulation method, a simulation system, a device, and a medium for an AC-DC power system that can adopt different simulation methods for the AC power grid and the DC power grid, so as to balance simulation accuracy and simulation speed.

[0006] A simulation method for an AC-DC power system, the method comprising: decoupling the power grid to be simulated to obtain an AC power grid to be simulated and a DC power grid to be simulated; based on a first processor, using a preset electromagnetic transient simulation model to simulate the AC power grid to be simulated and determine an AC system simulation result; based on a second processor, using a preset logic gate array simulation model to simulate the DC power grid to be simulated and determine a DC system simulation result; obtaining, by the first processor, the DC system simulation result of the second processor, and determining a complete AC system simulation result of the power grid to be simulated according to the AC system simulation result and the DC system simulation result; obtaining, by the second processor, the AC system simulation result of the first processor, and determining a complete DC system simulation result of the power grid to be simulated according to the AC system simulation result and the DC system simulation result.

[0007] In one embodiment, the decoupling the power grid to be simulated to obtain an AC power grid to be simulated and a DC power grid to be simulated includes: constructing a Bergeyron transmission line model according to the power grid to be simulated; obtaining voltages and currents on both sides of the Bergeyron transmission line model according to the Bergeyron transmission line model, where the voltages and currents on both sides of the Bergeyron transmission line model include the voltage and current on the DC system side of the power grid to be simulated and the voltage and current on the AC system side. Decoupling the power grid to be simulated according to the voltage on the AC system side, the current on the AC system side, the voltage on the DC system side, and the current on the DC system side of the power grid to be simulated according to the Bergeyron transmission line model to obtain an AC power grid to be simulated and a DC power grid to be simulated.

[0008] In one embodiment, the decoupling the power grid to be simulated according to the voltage on the AC system side, the current on the AC system side, the voltage on the DC system side, and the current on the DC system side of the power grid to be simulated according to the Bergeyron transmission line model to obtain an AC power grid to be simulated and a DC power grid to be simulated includes:

[0009] Decoupling the power grid to be simulated by the following formula to determine the current value of the AC power grid to be simulated and the current value of the DC power grid to be simulated:

[0010] i km (t) = 1 / (Z + R / 4)v k (t) + I k (t - τ)

[0011] i mk (t) = 1 / (Z + R / 4)v m (t) + I m (t - τ)

[0012] where, ikm is the current value of the AC power grid to be simulated, v k is the voltage on the AC system side of the historical power grid to be simulated, I k is the current on the AC system side of the historical power grid to be simulated, i mk is the current value of the DC power grid to be simulated, v m is the voltage on the DC system side of the historical power grid to be simulated, I m is the current on the DC system side of the historical power grid to be simulated, Z is the line wave impedance of the Berreling transmission line model, R is the lumped resistance value of the line of the Berreling transmission line model, t is time, and τ is the line transmission delay of the Berreling transmission line model.

[0013] In one embodiment, based on the first processor, using a preset electromagnetic transient simulation model, simulate the AC power grid to be simulated to determine the AC system simulation result; based on the second processor, using a preset logic gate array simulation model, simulate the DC power grid to be simulated to determine the DC system simulation result, including: based on the first processor, using the electromagnetic transient simulation model to simulate the AC power grid to be simulated according to a first preset simulation step size; based on the second processor, using the logic gate array simulation model to simulate the DC power grid to be simulated according to a second preset simulation step size, where the first preset simulation step size is greater than the second preset simulation step size, and the first preset simulation step size is an integer multiple of the second preset simulation step size.

[0014] In one embodiment, both the AC system simulation result and the DC system simulation result include simulation time, current and voltage information. Obtaining the DC system simulation result of the second processor based on the first processor, and determining the complete AC system simulation result of the power grid to be simulated according to the AC system simulation result and the DC system simulation result, includes: based on the first processor, obtaining the DC system simulation result and reading the simulation time of the DC system simulation result; if the simulation time of the DC system simulation result is the same as the simulation time of the current AC system simulation result of the first processor, then determining and storing the current complete AC system simulation result of the power grid to be simulated according to the current and voltage information of the DC system simulation result and the current AC system simulation result; if the simulation time of the DC system simulation result is different from the simulation time of the current AC system simulation result of the first processor, then reading the AC system simulation result with the same simulation time as the DC system simulation result, and determining and storing the complete AC system simulation result of the power grid to be simulated at the simulation time according to the current and voltage information of the DC system simulation result and the AC system simulation result with the same simulation time; every first preset time period, sending the stored complete AC system simulation result of the power grid to be simulated to the second processor.

[0015] In one embodiment, obtaining the AC system simulation result of the first processor based on the second processor, and determining the complete DC system simulation result of the power grid to be simulated according to the AC system simulation result and the DC system simulation result, includes: based on the second processor, obtaining the AC system simulation result and reading the simulation time of the AC system simulation result; if the simulation time of the AC system simulation result is the same as the simulation time of the current DC system simulation result of the second processor, then determining and storing the current complete DC system simulation result of the power grid to be simulated according to the current and voltage information of the AC system simulation result and the current DC system simulation result; if the simulation time of the AC system simulation result is different from the simulation time of the current DC system simulation result of the second processor, then reading the DC system simulation result with the same simulation time as the AC system simulation result, and determining and storing the complete DC system simulation result of the power grid to be simulated at the simulation time according to the current and voltage information of the AC system simulation result and the DC system simulation result with the same simulation time; every second preset time period, sending the stored complete DC system simulation result of the power grid to be simulated to the first processor.

[0016] In one embodiment, determining the complete AC system simulation result of the power grid to be simulated according to the AC system simulation result and the DC system simulation result includes: based on the first processor, obtaining the DC system simulation result at fixed time intervals; taking the average of the DC system simulation results within the fixed time interval to obtain an average DC system simulation result, where the average DC system simulation result includes the current on the average DC system side and the voltage on the average DC system side; determining the complete AC system simulation result of the power grid to be simulated according to the AC system simulation result and the average DC system simulation result, and the fixed time interval is greater than the first preset simulation step size.

[0017] In one embodiment, determining the complete AC system simulation result of the power grid to be simulated according to the AC system simulation result and the average DC system simulation result includes:

[0018] Determining the complete AC system simulation result of the power grid to be simulated through the following formula:

[0019] I k1 =(B1v k +B3i km )+(B2v m1 +B4i mk1 )

[0020] where I k1 is the complete AC system simulation result of the AC power grid to be simulated, v k is the historical voltage value of the AC power grid to be simulated, i km is the current value of the AC power grid to be simulated at present, v m1 is the voltage on the average DC system side, i mk1 is the current on the average DC system side, Z is the line wave impedance of the Berreman transmission line model, and R is the line lumped resistance value of the Berreman transmission line model.

[0021] In one embodiment, determining the complete DC system simulation result of the power grid to be simulated according to the AC system simulation result and the DC system simulation result includes: based on the second processor, obtaining the AC system simulation result at fixed time intervals; performing interpolation processing on the AC system simulation result at intervals of the second preset simulation step size to obtain multiple interpolated AC system simulation results, where the interpolated AC system simulation results include the current on the interpolated AC system side and the voltage on the interpolated AC system side; determining the complete DC system simulation result of the power grid to be simulated according to the multiple interpolated AC system simulation results and the DC system simulation result.

[0022] In one embodiment, determining the complete DC system simulation result of the power grid to be simulated according to the multiple interpolated AC system simulation results and the DC system simulation results includes:

[0023] Determine the complete DC system simulation result of the power grid to be simulated through the following formula:

[0024] I m1 = (B1v m + B3i mk ) + (B2v k1 + B4i km1 )

[0025] where I m1 is the complete DC system simulation result of the AC power grid to be simulated, v m is the voltage value of the historical DC power grid to be simulated, i mk is the current value of the current DC power grid to be simulated, v k1 is the voltage on the interpolated AC system side, i km1 is the current on the interpolated AC system side, Z is the line wave impedance of the Bergeyron transmission line model, and R is the line lumped resistance value of the Bergeyron transmission line model

[0026] A simulation system for an AC-DC power system, characterized in that the system includes: a host computer, a first processor, and a second processor, and the host computer, the first processor, and the second processor are all connected to each other. Among them, the host computer is used to decouple the power grid to be simulated to obtain an AC power grid to be simulated and a DC power grid to be simulated; the first processor is used to simulate the AC power grid to be simulated by using a preset electromagnetic transient simulation model to determine an AC system simulation result; the second processor is used to simulate the DC power grid to be simulated by using a preset logic gate array simulation model to determine a DC system simulation result; the first processor is further used to obtain the DC system simulation result of the second processor and determine the complete AC system simulation result of the power grid to be simulated according to the AC system simulation result and the DC system simulation result; the second processor is further used to obtain the AC system simulation result of the first processor and determine the complete DC system simulation result of the power grid to be simulated according to the AC system simulation result and the DC system simulation result.

[0027] In one embodiment, the second processor includes: a network communication module, configured to send the DC system simulation result determined by the second processor to the first processor via Ethernet, and obtain the AC system simulation result determined by the first processor.

[0028] A computer device includes a memory and a processor. The memory stores a computer program. When the processor executes the computer program, the following steps are implemented: decouple the power grid to be simulated to obtain an AC power grid to be simulated and a DC power grid to be simulated; based on a first processor, use a preset electromagnetic transient simulation model to simulate the AC power grid to be simulated and determine an AC system simulation result; based on a second processor, use a preset logic gate array simulation model to simulate the DC power grid to be simulated and determine a DC system simulation result; obtain the DC system simulation result of the second processor based on the first processor, and determine a complete AC system simulation result of the power grid to be simulated according to the AC system simulation result and the DC system simulation result; obtain the AC system simulation result of the first processor based on the second processor, and determine a complete DC system simulation result of the power grid to be simulated according to the AC system simulation result and the DC system simulation result.

[0029] A computer-readable storage medium stores a computer program. When the computer program is executed by a processor, the following steps are implemented: decouple the power grid to be simulated to obtain an AC power grid to be simulated and a DC power grid to be simulated; based on a first processor, use a preset electromagnetic transient simulation model to simulate the AC power grid to be simulated and determine an AC system simulation result; based on a second processor, use a preset logic gate array simulation model to simulate the DC power grid to be simulated and determine a DC system simulation result; obtain the DC system simulation result of the second processor based on the first processor, and determine a complete AC system simulation result of the power grid to be simulated according to the AC system simulation result and the DC system simulation result; obtain the AC system simulation result of the first processor based on the second processor, and determine a complete DC system simulation result of the power grid to be simulated according to the AC system simulation result and the DC system simulation result.

[0030] The simulation method, simulation system, device, and medium of the above AC-DC power system decouple the power grid to be simulated, dividing it into an AC power grid and a DC power grid, enabling separate simulation of the AC power grid and the DC power grid. By using an electromagnetic transient simulation model with the first processor to simulate the AC power grid, the simulation results of the AC system can be obtained. Due to the characteristics of the AC power grid resulting in fewer nodes in the AC power grid, using the electromagnetic transient simulation model to simulate the AC power grid can adapt to the characteristics of fewer nodes in the AC power grid, making the simulation faster, thus enabling the faster acquisition of the simulation results of the AC system and sending them to the second processor, facilitating the improvement of the simulation speed of the power grid to be simulated. By using a logic gate array simulation model with the second processor to simulate the DC power grid, since there are more nodes in the DC power grid, in order to ensure the accuracy of the simulation results, a more detailed simulation of the DC power grid is required. Due to the parallel solution characteristics of the logic gate array simulation model, it is more suitable for simulating the DC power grid, which can ensure the accuracy of the simulation results of the DC power grid, thus enabling the acquisition of more accurate simulation results of the DC system and sending them to the first processor, facilitating the improvement of the simulation accuracy of the power grid to be simulated. By the first processor obtaining the simulation results of the DC system of the second processor and based on the simulation results of the DC system of the second processor and its own simulation results of the AC system, the complete simulation results of the AC system of the power grid to be simulated can be obtained, and the decoupled simulation results of the AC system and the DC system can be merged again to obtain the complete simulation results of the AC system of the power grid to be simulated. By the second processor obtaining the simulation results of the AC system of the first processor and based on the simulation results of the AC system of the first processor and its own simulation results of the DC system, the complete simulation results of the DC system of the power grid to be simulated can be obtained, thus enabling the decoupled simulation results of the AC system and the DC system to be merged again to obtain the complete simulation results of the DC system of the power grid to be simulated. Through the method of this application, the power grid to be simulated is decoupled, enabling the use of the most suitable simulation models for the different characteristics of the AC power grid and the DC power grid respectively for simulation, taking into account both simulation accuracy and simulation speed, and data interaction is carried out during the simulation process, so that the final simulation results are still the simulation results of the entire power grid to be simulated, thus improving the simulation speed while ensuring the simulation accuracy and accuracy. Description of the Drawings

[0031] In order to more clearly illustrate the technical solutions in the embodiments of the present application or in the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0032] Figure 1Flowchart of the simulation method for an AC-DC power system in an embodiment;

[0033] Figure 2 Flowchart of the method for decoupling the power grid to be simulated in an embodiment;

[0034] Figure 3 Schematic circuit diagram of the Bergeyron transmission line model in an embodiment;

[0035] Figure 4 Schematic circuit equivalent diagram of the Bergeyron transmission line model in an embodiment;

[0036] Figure 5 Flowchart of the method for data interaction processing of the first processor in an embodiment;

[0037] Figure 6 Flowchart of the method for data interaction processing of the second processor in an embodiment;

[0038] Figure 7 Flowchart of the method for the first processor to determine the simulation result of the complete AC system in an embodiment;

[0039] Figure 8 Flowchart of the method for the second processor to determine the simulation result of the complete DC system in an embodiment;

[0040] Figure 9 Schematic diagram of the interpolation process in an embodiment;

[0041] Figure 10 Schematic diagram of the FPGA module in an embodiment;

[0042] Figure 11 Schematic structural diagram of the simulation scenario in an embodiment;

[0043] Figure 12 Waveform diagram of the current on the AC system side in an embodiment;

[0044] Figure 13 Waveform diagram of the voltage on the AC system side in an embodiment;

[0045] Figure 14 Waveform diagram of the voltage on the DC system side in an embodiment;

[0046] Figure 15 Schematic diagram of the simulation error in an embodiment;

[0047] Figure 16 Structural diagram of the simulation system for the AC-DC power system in an embodiment;

[0048] Figure 17Internal structure diagram of a computer device in an embodiment. Detailed implementation

[0049] To facilitate understanding of this application, the following will provide a more comprehensive description of this application with reference to relevant accompanying drawings. Embodiments of this application are shown in the accompanying drawings. However, this application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of this application more thorough and comprehensive.

[0050] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which this application belongs. The terms used in the specification of this application herein are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0051] It can be understood that the terms "first", "second", etc. used in this application can be used herein to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish the first element from another element.

[0052] It should be noted that when an element is considered to be "connected" to another element, it can be directly connected to the other element or connected to the other element through an intermediate element. In addition, in the following embodiments, "connection", if there is a transmission of electrical signals or data between the connected objects, should be understood as "electrical connection", "communication connection", etc.

[0053] As used herein, the singular forms "a", "an", and "the" may also include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms "comprising", "including", or "having", etc. specify the presence of the stated features, wholes, steps, operations, components, parts, or combinations thereof, but do not exclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts, or combinations thereof.

[0054] As described in the background art, the power system simulation platforms in the prior art have the problem that they can only simulate the entire power system using the same simulation method, thus being unable to balance simulation accuracy and simulation speed.

[0055] For the above reasons, the present invention provides a simulation method, simulation system, device, and medium for an AC-DC power system that can adopt different simulation methods for AC power grids and DC power grids, thereby balancing simulation accuracy and simulation speed.

[0056] In one embodiment, as Figure 1 shown, a simulation method for an AC-DC power system is provided. The method includes:

[0057] Step S100: Decouple the power grid to be simulated to obtain an AC power grid to be simulated and a DC power grid to be simulated.

[0058] Step S120: Based on the first processor, use a preset electromagnetic transient simulation model to simulate the AC power grid to be simulated and determine the simulation results of the AC system.

[0059] Specifically, based on the first processor, use the electromagnetic transient simulation model to simulate the AC power grid to be simulated according to the first preset simulation step length. The first processor can be a CPU (Central Processing Unit), and the electromagnetic transient simulation model can be any currently common or self-developed electromagnetic transient simulation program. For example, the electromagnetic transient simulation program is the ESP (Electromagnetic Simulation Program) independently developed by the System Research Institute of China Southern Power Grid. This program uses the nodal analysis method to solve the electromagnetic transient simulation program. Currently, an electromagnetic transient simulation model including all components of the power system has been developed, and the data structure uses cards to fill in the parameters of each component, with a fixed data format, simple to use and high simulation accuracy.

[0060] Step S140: Based on the second processor, use a preset logic gate array simulation model to simulate the DC power grid to be simulated and determine the simulation results of the DC system.

[0061] Specifically, based on the second processor, use the logic gate array simulation model to simulate the DC power grid to be simulated according to the second preset simulation step length. The second processor can be an FPGA (Field Programmable Gate Array), which has the characteristic of parallel computing. The first preset simulation step length is greater than the second preset simulation step length, and the first preset simulation step length is an integer multiple of the second preset simulation step length. The simulation step length is the time interval between two simulations.

[0062] Specifically, the first processor uses an electromagnetic transient simulation model to simulate the AC power grid to be simulated according to the first preset simulation step size, and the second processor uses a logic gate array simulation model to simulate the DC power grid to be simulated according to the second preset simulation step size. Thus, the different simulation characteristics of the first processor and the second processor can be utilized. That is, the simulation step size of the first processor is large, so the simulation speed is fast. At the same time, the number of nodes in the AC power grid is small, so even if the simulation step size is relatively large, it will not affect the simulation accuracy of the AC power grid. The simulation step size of the second processor is small, so the simulation accuracy is higher, and the number of nodes in the DC power grid is large, and a smaller simulation step size is required to ensure the simulation accuracy. Therefore, based on the characteristics of the DC power grid and the AC power grid, combined with the characteristics of the first processor and the second processor, the simulation speed is increased while ensuring the simulation accuracy.

[0063] Step S160: Based on the first processor, obtain the DC system simulation result of the second processor, and determine the complete AC system simulation result of the power grid to be simulated according to the AC system simulation result and the DC system simulation result.

[0064] Step S180: Based on the second processor, obtain the AC system simulation result of the first processor, and determine the complete DC system simulation result of the power grid to be simulated according to the AC system simulation result and the DC system simulation result.

[0065] In this embodiment, by decoupling the power grid to be simulated, the power grid to be simulated is divided into an AC power grid and a DC power grid, so that the AC power grid and the DC power grid can be simulated separately. By using the electromagnetic transient simulation model, the first processor simulates the AC power grid, and the AC system simulation results can be obtained. Due to the characteristics of the AC power grid, the number of nodes in the AC power grid is small. Using the electromagnetic transient simulation model to simulate the AC power grid can adapt to the characteristics of the small number of nodes in the AC power grid, making the simulation speed faster, so that the AC system simulation results can be obtained more quickly and sent to the second processor, which is convenient for improving the simulation speed of the power grid to be simulated. By using the logic gate array simulation model, the second processor simulates the DC power grid. Since the number of nodes in the DC power grid is large, in order to ensure the accuracy of the simulation results, a more detailed simulation of the DC power grid is required. Since the logic gate array simulation model has the characteristic of parallel solution, it is more suitable for simulating the DC power grid, which can ensure the accuracy of the DC power grid simulation results, so that more accurate DC system simulation results can be obtained and sent to the first processor, which is convenient for improving the simulation accuracy of the power grid to be simulated. The first processor obtains the DC system simulation results of the second processor, and according to the DC system simulation results of the second processor and its own AC system simulation results, the complete AC system simulation results of the power grid to be simulated can be obtained, and the decoupled AC system simulation results and DC system simulation results can be recombined to obtain the complete AC system simulation results of the power grid to be simulated. The second processor obtains the AC system simulation results of the first processor, and according to the AC system simulation results of the first processor and its own DC system simulation results, the complete DC system simulation results of the power grid to be simulated can be obtained, so that the decoupled AC system simulation results and DC system simulation results can be recombined to obtain the complete DC system simulation results of the power grid to be simulated. By using the method of this application, the power grid to be simulated is decoupled, so that the most suitable simulation model can be used to simulate the AC power grid and the DC power grid respectively according to their different characteristics, taking into account both the simulation accuracy and the simulation speed, and data interaction is carried out during the simulation process, so that the final simulation results are still the simulation results of the entire power grid to be simulated, thus improving the simulation speed while ensuring the simulation accuracy and accuracy.

[0066] In one embodiment, as Figure 2 shown, step S100 includes:

[0067] Step S1002, constructing a Bergeon transmission line model according to the power grid to be simulated.

[0068] Exemplarily, when the physical dimensions of an electrical component are very small compared to the wavelength of the electromagnetic wave it transmits, the propagation time can be neglected, and this component is a lumped element, satisfying the so-called lumped element assumption: at any moment, the magnitude of the current flowing into one terminal of a two-terminal element is equal to the magnitude of the current flowing out of the other terminal. When using overhead lines or cables to transmit energy in power transmission, generally the length of such lines is not "very small" compared to the wavelength, and even has the same order of magnitude as the wavelength. At this time, the transmission line does not satisfy the lumped element assumption. If the concept of lumped parameters is still used to analyze the transmission line, a large error will be introduced. In this case, the concept of distributed parameters needs to be used for analysis. The Bergeron line model is derived from the equations of uniform lossless transmission lines, and the line is appropriately divided into several segments. The loss of the line is equivalent to a lumped resistance and the resistance is connected to both ends of each segment. Since the LC parameters in the equations of uniform transmission lines are the line parameters at the fundamental frequency of 50 Hz, therefore, the Bergeron line model is often used for various studies at the fundamental frequency impedance, such as studying line short circuits and power flow transfer. If the simulation step size is 50 μs, 53.0×10 km / s·50 μs = 15 km, which means that lines longer than 15 km should use the Bergeron equivalent circuit and utilize the natural delay characteristic of the Bergeron model to achieve decoupling.

[0069] Exemplarily, as Figure 3 shown, the power grid to be simulated is divided into a DC power grid to be simulated and an AC power grid to be simulated. The DC power grid to be simulated and the AC power grid to be simulated are connected by a line. The total resistance of this line is R and the total inductance is L. It is equivalently distributed into multiple small segments, and virtual additional capacitors C' are added at both ends of each small segment of the line. Among them, the values of C', R', and L' are all preset unit sizes. i km is the current value of the AC power grid to be simulated, v k is the voltage on the AC system side of the historical power grid to be simulated, i mk is the current value of the DC power grid to be simulated, v m is the voltage on the DC system side of the historical power grid to be simulated. Thus, the parameters of the power grid to be simulated are distributed, and the Bergeron transmission line model is constructed.

[0070] Step S1004, according to the Bergeron transmission line model, obtain the voltages and currents on both sides of the Bergeron transmission line model.

[0071] Specifically, the voltages and currents on both sides of the Bergeron transmission line model include the voltages and currents on the DC system side and the AC system side of the power grid to be simulated.

[0072] Step S1006: According to the Berliou transmission line model, decouple the power grid to be simulated based on the voltage on the AC system side of the power grid to be simulated, the current on the AC system side, the voltage on the DC system side, and the current on the DC system side, to obtain the AC power grid to be simulated and the DC power grid to be simulated.

[0073] Specifically, as Figure 4 shown, use the Norton equivalent circuit to equivalently represent the DC power grid and the AC power grid as a current source in parallel with a resistor respectively, and decouple the power grid to be simulated through the following formula to determine the current value of the AC power grid to be simulated and the current value of the DC power grid to be simulated:

[0074] i km (t) = 1 / (Z + R / 4)v k (t) + I k (t - τ)

[0075] i mk (t) = 1 / (Z + R / 4)v m (t) + I m (t - τ)

[0076] Among them, i km is the current value of the AC power grid to be simulated, v k is the voltage on the AC system side of the historical power grid to be simulated, I k is the current on the AC system side of the historical power grid to be simulated, i mk is the current value of the DC power grid to be simulated, v m is the voltage on the DC system side of the historical power grid to be simulated, I m is the current on the DC system side of the historical power grid to be simulated, Z is the line wave impedance of the Berliou transmission line model, R is the line lumped resistance value of the Berliou transmission line model, t is time, and τ is the line transmission delay of the Berliou transmission line model. It can be seen from the above formula that the current value of the AC power grid to be simulated is only related to the voltage on the AC system side of the historical power grid to be simulated and the current on the AC system side of the historical power grid to be simulated, and has nothing to do with the voltage on the DC system side and the current on the DC system side. Similarly, the current value of the DC power grid to be simulated is only related to the voltage on the DC system side of the historical power grid to be simulated and the current on the DC system side of the historical power grid to be simulated, and has nothing to do with the voltage on the AC system side and the current on the AC system side. Therefore, the decoupling process of the power grid to be simulated is realized.

[0077] Exemplarily, determine the line wave impedance Z of the Berliou transmission line model through the following formula:

[0078]

[0079] Among them, the values of C' and L' are both preset unit sizes, that is, the sum of all L' in the circuit is equal to the total inductance L of the circuit.

[0080] The line transmission delay τ of the Berreman transmission line model is determined by the following formula:

[0081]

[0082] Among them, d is the total length of the line, and the values of C' and L' are both preset unit sizes.

[0083] In this embodiment, first, a Berreman transmission line model is constructed according to the power grid to be simulated. By using the natural delay characteristic of the Berreman transmission line model, enough time can be provided for the power grid to be simulated during the simulation process, so that when the power grid to be simulated is divided into a DC power grid and an AC power grid, the simulations of the DC power grid and the AC power grid can be carried out in parallel, and data interaction is performed every certain time. By obtaining the voltage on the AC system side of the power grid to be simulated, the current on the AC system side, the voltage on the DC system side, and the current on the DC system side, the current on the AC system side and the current on the DC system side at the next moment can be calculated respectively. And due to the constructed Berreman transmission line model, the current value of the AC power grid to be simulated only relates to the voltage on the AC system side of the power grid to be simulated in history and the current on the AC system side of the power grid to be simulated in history, and has nothing to do with the voltage on the DC system side and the current on the DC system side. Similarly, the current value of the DC power grid to be simulated only relates to the voltage on the DC system side of the power grid to be simulated in history and the current on the DC system side of the power grid to be simulated in history, and has nothing to do with the voltage on the AC system side and the current on the AC system side. Therefore, the decoupling process of the power grid to be simulated is realized.

[0084] In one embodiment, the simulation results of the AC system and the simulation results of the DC system both include simulation time, current and voltage information, such as Figure 5 shown, step S160 includes:

[0085] Step S1602, based on the first processor, obtain the simulation results of the DC system and read the simulation time of the simulation results of the DC system.

[0086] Exemplarily, the first processor receives the simulation results of the DC system sent by the Berreman transmission line model through Ethernet.

[0087] Step S1604, if the simulation time of the simulation results of the DC system is the same as the simulation time of the current simulation results of the AC system of the first processor, then determine and store the current complete simulation results of the AC system of the power grid to be simulated according to the current and voltage information of the simulation results of the DC system and the current and voltage information of the current simulation results of the AC system.

[0088] Exemplarily, the DC system simulation results are transmitted in the form of packet messages. After the first processor receives the packet messages, it checks the time stamp in the packet messages. If the time stamp is the same as that of the first processor, it calculates the current complete AC system simulation results of the power grid to be simulated based on the DC system simulation results and its own AC system simulation results and stores them.

[0089] Step S1606, if the simulation time of the DC system simulation results is different from the simulation time of the current AC system simulation results of the first processor, read the AC system simulation results with the same simulation time as the DC system simulation results, and determine and store the complete AC system simulation results of the power grid to be simulated at the simulation time according to the current and voltage information of the DC system simulation results and the current and voltage information of the AC system simulation results with the same simulation time.

[0090] Exemplarily, if the time stamp in the packet message is different from that of the first processor, store the packet message in the buffer, and find the AC system simulation results with the same time stamp as the DC system simulation results in its own AC system simulation results, and then calculate and store the complete AC system simulation results of the power grid to be simulated at the corresponding simulation time according to the DC system simulation results and the AC system simulation results with the same time stamp.

[0091] Step S1608, every first preset time period, send the stored complete AC system simulation results of the power grid to be simulated to the second processor.

[0092] Specifically, the first preset time period is the time required for the first processor to completely calculate a complete AC system simulation result.

[0093] Exemplarily, the complete AC system simulation results of the power grid to be simulated calculated by the first processor are all stored in the buffer area. After adding UDP, IPv6, and Ethernet headers to the complete AC system simulation results every fixed time period, they are sent to the second processor.

[0094] In this embodiment, when the first processor receives the DC system simulation results, it first reads the simulation time of the DC system simulation results, then reads the AC system simulation results with the same simulation time in its own AC system simulation results according to the simulation time, and then calculates and stores the complete AC system simulation results of the power grid to be simulated at the corresponding simulation time according to the DC system simulation results and the AC system simulation results with the same simulation time. And every fixed time period, send the stored complete AC system simulation results to the second processor. The data interaction between the first processor and the second processor is realized.

[0095] In one embodiment, as Figure 6 shown, step S180 includes:

[0096] Step S1802: Based on the second processor, obtain the AC system simulation result and read the simulation time of the AC system simulation result.

[0097] Exemplarily, the second processor receives the AC system simulation result sent by the Bergeon transmission line model through Ethernet.

[0098] Step S1804: If the simulation time of the AC system simulation result is the same as the simulation time of the current DC system simulation result of the second processor, then determine the current complete DC system simulation result of the power grid to be simulated according to the current and voltage information of the AC system simulation result and the current and voltage information of the current DC system simulation result, and store it.

[0099] Exemplarily, the AC system simulation result is transmitted in the form of a packet. After the second processor receives the packet, it checks the time stamp in the packet. If the time stamp is consistent with the time stamp of the second processor, then calculate the current complete DC system simulation result of the power grid to be simulated according to the AC system simulation result and its own DC system simulation result, and store it.

[0100] Step S1806: If the simulation time of the AC system simulation result is different from the simulation time of the current DC system simulation result of the second processor, then read the DC system simulation result with the same simulation time as the AC system simulation result, and determine the complete DC system simulation result of the power grid to be simulated at the simulation time according to the current and voltage information of the AC system simulation result with the same simulation time and the current and voltage information of the DC system simulation result, and store it.

[0101] Exemplarily, if the time stamp in the packet is inconsistent with the time stamp of the second processor, then store the packet in the buffer, and find the DC system simulation result in its own DC system simulation results that is consistent with the time stamp of the AC system simulation result, and then calculate the complete DC system simulation result of the power grid to be simulated at the corresponding simulation time according to the DC system simulation result and the AC system simulation result with the same time stamp, and store it.

[0102] Step S1808: Every second preset duration, send the stored complete DC system simulation result of the power grid to be simulated to the first processor.

[0103] Specifically, the second preset duration is the time required for the second processor to completely calculate a complete DC system simulation result.

[0104] Exemplarily, the complete DC system simulation results of the power grid to be simulated calculated by the second processor are all stored in the buffer. Every fixed duration, after adding UDP, IPv6, and Ethernet headers to the complete DC system simulation result, it is sent to the first processor.

[0105] In this embodiment, when the second processor receives the AC system simulation result, it first reads the simulation time of the AC system simulation result, and then according to this simulation time, reads the DC system simulation result with the same simulation time in its own DC system simulation results. Then, it calculates the complete DC system simulation result of the power grid to be simulated at the corresponding simulation time based on the AC system simulation result and the DC system simulation result with the same simulation time, and stores it. And every fixed time interval, it sends the stored complete DC system simulation result to the first processor. Thus, the data interaction between the second processor and the first processor is realized.

[0106] In one embodiment, as Figure 7 shown, step S160 includes:

[0107] Step S1620, based on the first processor, obtain the DC system simulation result at fixed time intervals.

[0108] Exemplarily, the fixed time interval is 50 microseconds. The first processor receives the DC system simulation result sent by the second processor every 50 microseconds.

[0109] Specifically, at the moment when the simulations of the first processor and the second processor are synchronized, the historical item current values of both the first processor and the second processor are updated. For the first processor, the simulation result at time t is calculated within the interval from t - ΔT to t, and the corresponding historical item current value represents the change of the first processor within the interval from t - ΔT to t. For the second processor, multiple simulation steps have been performed within the ΔT interval, and the corresponding historical item current value represents the change of the second processor within the interval from t - Δt to t.

[0110] Step S1640, take the average value of the DC system simulation results within the fixed time interval to obtain the average DC system simulation result, where the average DC system simulation result includes the current on the average DC system side and the voltage on the average DC system side.

[0111] Exemplarily, the first processor takes the average value of the DC system simulation results received within the fixed time interval to obtain the average DC system simulation result.

[0112] Step S1660, determine the complete AC system simulation result of the power grid to be simulated according to the AC system simulation result and the average DC system simulation result, where the fixed time interval is greater than the first preset simulation step.

[0113] Specifically, through the following formula, determine the complete AC system simulation result of the power grid to be simulated:

[0114] I k1 =(B1v k +B3i km )+(B2v m1 +B4imk1 )

[0115] Among them, I k1 is the complete AC system simulation result of the AC power grid to be simulated, v k is the historical voltage value of the AC power grid to be simulated, i km is the current value of the AC power grid to be simulated at present, v m1 is the voltage on the average DC system side, i mk1 is the current on the average DC system side, Z is the line wave impedance of the Berreman transmission line model, and R is the lumped resistance value of the line of the Berreman transmission line model.

[0116] In this embodiment, the first processor substitutes the AC system simulation result within a fixed time period of itself and the average value of the obtained DC system simulation result into the calculation formula to obtain the complete AC system simulation result of the power grid to be simulated. Thus, the combination of the AC system simulation result of the first processor and the DC system simulation result of the second processor is realized, and the complete AC system simulation result of the power grid to be simulated is obtained. While ensuring the simulation speed, the complete AC system simulation result of the power grid to be simulated is accurately calculated.

[0117] In one embodiment, as Figure 8 shown, step S180 includes:

[0118] Step S1820, based on the second processor, obtain the AC system simulation result at intervals of a fixed time period.

[0119] Step S1840, perform interpolation processing on the AC system simulation result at intervals of a second preset simulation step length to obtain multiple interpolated AC system simulation results. The interpolated AC system simulation results include the current on the interpolated AC system side and the voltage on the interpolated AC system side.

[0120] Exemplarily, let the second preset simulation step length be Δt, and the first preset simulation step length be ΔT = N * Δt. Then within the time of N * Δt, the second processor will perform N times of simulation solutions.

[0121] According to the calculation formula of the power grid, the nodal equation for the kth simulation solution is:

[0122]

[0123] Among them, G f is the susceptance matrix of the power grid, v f is the voltage matrix of the power grid, i f is the current matrix of the power grid, and the rest are unknowns.

[0124] Use the interpolation method to replace these unknowns. The formula for the interpolated value is as follows:

[0125]

[0126] Among them, I f , s is the simulation result of the AC system obtained within the interval duration. For example, as Figure 9 shown, within the ΔT time, the first processor has two simulation results, at the t - ΔT moment and the t moment respectively. And within the ΔT time, the second processor obtained 5 simulation results. Then interpolation processing needs to be performed between the two simulation results of the first processor, with the second preset step size as the interpolation interval, inserting 3 values to make it 5 simulation results, so as to correspond one by one with the simulation results obtained by the second processor and improve the accuracy of the calculation results.

[0127] Step S1860, determine the complete DC system simulation result of the power grid to be simulated according to multiple interpolated AC system simulation results and DC system simulation results.

[0128] Specifically, through the following formula, determine the complete DC system simulation result of the power grid to be simulated:

[0129] I m1 =(B1v m +B3i mk )+(B2v k1 +B4i km1 )

[0130] Among them, I m1 is the complete DC system simulation result of the AC power grid to be simulated, v m is the voltage value of the historical DC power grid to be simulated, i mk is the current value of the current DC power grid to be simulated, v k1 is the voltage on the interpolated AC system side, i km1 is the current on the interpolated AC system side, Z is the line wave impedance of the Bergeyron transmission line model, and R is the line lumped resistance value of the Bergeyron transmission line model.

[0131] Exemplarily, as Figure 10 shown, Figure 10 is the structural diagram of the interpolation processing module in the FPGA. This module contains four random access memories RAM, one read-only memory ROM integer , one first-in first-out queue FIFO x , and adopts the design idea of pipeline to realize the calculation of interpolation point data. Among them, RAM t and RAM h respectively store the two end data x h and x τ to be interpolated, RAMΔx_xN With the RAM x_xN Separate storage of x h And x τ The difference Δx, and the end data x τ , and the stored data is read N times repeatedly, where N is the number of interpolation operations. The storage format of the ROM integer Is {0, 0, …0, 1, 1, …1, …N - 1, N - 1, …, N - 1}, where the number of elements is equal to the number of data to be interpolated. Thus, the above interpolation operation is implemented through the FPGA.

[0132] In this embodiment, the second processor interpolates based on the DC system simulation results within its own fixed time duration and the obtained AC system simulation results, substitutes the DC system simulation results and the interpolated AC system simulation results into the calculation formula, and obtains the complete DC system simulation results of the power grid to be simulated. Thus, the combination of the AC system simulation results of the first processor and the DC system simulation results of the second processor is realized, and the complete DC system simulation results of the power grid to be simulated are obtained. While ensuring the simulation speed, the complete AC system simulation results of the power grid to be simulated are accurately calculated.

[0133] In one embodiment, the simulation method of the AC-DC power system further includes:

[0134] Construct a simulation test case to verify the performance of the simulation method of the AC-DC power system.

[0135] Specifically, build a simulation scenario as shown in Figure 11 . Set the transient scenario as a three-phase short-circuit fault suddenly occurring at 3 s for an MMC (modular multilevel converter), with a duration of 0.2 s. Use the traditional PSCAD (Power Systems Computer Aided Design) electromagnetic transient simulation software to simulate this simulation scenario, and then use the CPU and FPGA to simulate this simulation scenario using the method of this application.

[0136] The simulation waveforms are as shown in Figure 12 , 13 , 14, and the simulation errors are as shown in Figure 15 . The simulation errors are within 3%.

[0137] The simulation speed is as shown in Table 1 below

[0138] Table 1. Comparison of simulation times

[0139]

[0140] In this embodiment, by building a simulation test scenario and simulating the simulation scenario using the traditional method and the method of the present application respectively, it can be seen that the simulation error is very small, but the simulation speed of the method of the present application is greatly improved compared with the traditional simulation speed.

[0141] In one embodiment, as Figure 16 shown, a simulation system for an AC-DC power system is provided, characterized in that the system includes: a host computer 10, a first processor 20, and a second processor 30. The host computer 10, the first processor 20, and the second processor 30 are all connected to each other. Among them,

[0142] The host computer 10 is used to decouple the power grid to be simulated to obtain the AC power grid to be simulated and the DC power grid to be simulated;

[0143] The first processor 20 is used to simulate the AC power grid to be simulated by using a preset electromagnetic transient simulation model to determine the AC system simulation result;

[0144] The second processor 30 is used to simulate the DC power grid to be simulated by using a preset logic gate array simulation model to determine the DC system simulation result;

[0145] The first processor 20 is further used to obtain the DC system simulation result of the second processor 30, and determine the complete AC system simulation result of the power grid to be simulated according to the AC system simulation result and the DC system simulation result;

[0146] The second processor 30 is further used to obtain the AC system simulation result of the first processor 20, and determine the complete DC system simulation result of the power grid to be simulated according to the AC system simulation result and the DC system simulation result.

[0147] In this embodiment, by decoupling the power grid to be simulated, the power grid to be simulated is divided into an AC power grid and a DC power grid, so that the AC power grid and the DC power grid can be simulated separately. By using the electromagnetic transient simulation model, the first processor simulates the AC power grid, and the AC system simulation results can be obtained. Due to the characteristics of the AC power grid, the number of nodes in the AC power grid is small. Using the electromagnetic transient simulation model to simulate the AC power grid can adapt to the characteristics of the small number of nodes in the AC power grid, making the simulation speed faster, so that the AC system simulation results can be obtained more quickly and sent to the second processor, which is convenient for improving the simulation speed of the power grid to be simulated. By using the logic gate array simulation model, the second processor simulates the DC power grid. Since the number of nodes in the DC power grid is large, in order to ensure the accuracy of the simulation results, a more detailed simulation of the DC power grid is required. Since the logic gate array simulation model has the characteristic of parallel solution, it is more suitable for simulating the DC power grid, which can ensure the accuracy of the DC power grid simulation results, so that more accurate DC system simulation results can be obtained and sent to the first processor, which is convenient for improving the simulation accuracy of the power grid to be simulated. The first processor obtains the DC system simulation results of the second processor, and combines them according to the DC system simulation results of the second processor and its own AC system simulation results, so as to obtain the complete AC system simulation results of the power grid to be simulated, so that the decoupled AC system simulation results and DC system simulation results can be recombined to obtain the complete AC system simulation results of the power grid to be simulated. The second processor obtains the AC system simulation results of the first processor, and combines them according to the AC system simulation results of the first processor and its own DC system simulation results, so as to obtain the complete DC system simulation results of the power grid to be simulated, so that the decoupled AC system simulation results and DC system simulation results can be recombined to obtain the complete AC-DC system simulation results of the power grid to be simulated. By the method of this application, the power grid to be simulated is decoupled, so that the most suitable simulation model can be used to simulate the AC power grid and the DC power grid respectively according to their different characteristics, taking into account both the simulation accuracy and the simulation speed, and data interaction is carried out during the simulation process, so that the final simulation results are still the simulation results of the entire power grid to be simulated, thus improving the simulation speed while ensuring the simulation accuracy and accuracy.

[0148] In one embodiment, the second processor 30 includes: a network communication module.

[0149] The network communication module is configured to send the DC system simulation results determined by the second processor 30 to the first processor 20 through Ethernet, and obtain the AC system simulation results determined by the first processor 20.

[0150] Specifically, the network communication module includes: a network data transceiver module, a BerreLink interactive communication interface module, a shared RAM, a network communication processor, and a MAC module. Among them, the network data transceiver module communicates with the MAC module to realize the mutual transmission of network data and the shared RAM; the BerreLink interactive communication interface module transmits the network data transmitted by the Ethernet to the BerreLink interface module in the second processor, and reads the latest interaction amount from the BerreLink interface module in the second processor, so as to realize the data transfer between the second processor and the Ethernet; the network communication processor processes the network data in the shared RAM to implement various network protocols. The MAC module adopts a three-speed Ethernet core designed by Altera Corporation and is used to implement interface connection with the Ethernet chip.

[0151] Specifically, by setting a BerreLink interface module in the second processor, the decoupling between the AC-DC systems is realized, and the communication and synchronization between the first processor and the second processor are realized by using the network communication module (gigabit Ethernet communication medium).

[0152] Exemplarily, the first processor is generally connected to the second processor by means of direct connection or a dedicated gigabit switch to ensure the reliable transmission of high-speed data streams. After the first processor and the second processor form a local area network, the first processor and the second processor are respectively assigned an IPv6 (Internet Protocol Version 6) address and access each other through the IPv6 protocol. The network communication module in the second processor supports the ICMPv6 (Internet Control Message Protocol version 6) protocol, can realize automatic allocation of IPv6 addresses, and can respond to ICMPv6 neighbor query packets. The first processor does not need to configure static routes or static IP addresses, thus realizing plug-and-play.

[0153] In this embodiment, by setting a network communication module in the second processor, two-way high-speed data interaction between the first processor and the second processor is realized, so that the first processor and the second processor can be communicatively connected to transmit data.

[0154] It should be understood that although Figure 1 、 2 、5、6、7、8 in the flowchart of the steps are displayed in sequence according to the indication of the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless there is a clear description in this article, the execution of these steps has no strict order limit, and these steps can be executed in other orders. Moreover, Figure 1 、 2At least some of the steps 5, 6, 7, and 8 may include multiple steps or multiple stages. These steps or stages are not necessarily executed and completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be executed alternately or in turn with at least some of the steps or stages in other steps or other steps.

[0155] In one embodiment, a computer device is provided. The internal structure diagram of the computer device may be as Figure 17 shown. The computer device includes a processor, a memory, and a network interface connected via a system bus. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program, and a database. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The network interface of the computer device is used to communicate with an external terminal via a network connection. When the computer program is executed by the processor, it implements a simulation method for an AC-DC power system.

[0156] Those skilled in the art can understand that Figure 17 the structure shown in

[0157] is only a block diagram of some structures related to the solution of this application, and does not constitute a limitation on the computer device to which the solution of this application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine some components, or have a different component layout.

[0158] In one embodiment, a computer device is provided, including a memory and a processor. A computer program is stored in the memory. When the processor executes the computer program, it implements the steps in the above method embodiments.

[0159] Those of ordinary skill in the art can understand that all or part of the processes in the methods of the above embodiments can be completed by instructing relevant hardware through a computer program. The computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above methods. Among them, any reference to a memory, storage, database, or other medium used in the embodiments provided in the present application can include at least one of non-volatile and volatile memories. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, or optical memory, etc. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM), etc.

[0160] In the description of this specification, the description of reference terms such as "some embodiments", "other embodiments", "ideal embodiments", etc. means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic description of the above terms does not necessarily refer to the same embodiment or example.

[0161] The technical features of the above embodiments can be combined arbitrarily. For the sake of concise description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope described in this specification.

[0162] The above-described embodiments only represent several implementation manners of the present application. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several modifications and improvements can still be made, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. A simulation method for an AC-DC power system, characterized in that, The method includes: Decoupling the power grid to be simulated to obtain an AC power grid to be simulated and a DC power grid to be simulated; Based on a first processor, using a preset electromagnetic transient simulation model to simulate the AC power grid to be simulated and determining an AC system simulation result; Based on a second processor, using a preset logic gate array simulation model to simulate the DC power grid to be simulated and determining a DC system simulation result; Based on the first processor, obtaining the DC system simulation result of the second processor, and based on the first processor, obtaining the DC system simulation result at fixed time intervals; Taking the average of the DC system simulation results within the fixed time period to obtain an average DC system simulation result, where the average DC system simulation result includes the current on the average DC system side and the voltage on the average DC system side, and the fixed time period is greater than a first preset simulation step; Determining the complete AC system simulation result of the power grid to be simulated through the following formula: I k1 = (B1v k + B3i km ) + (B2v m1 + B4i mk1 ) Among them, I k1 is the complete AC system simulation result of the AC power grid to be simulated, v k is the historical voltage value of the AC power grid to be simulated, i km is the current value of the AC power grid to be simulated at present, v m1 is the voltage on the average DC system side, i mk1 is the current on the average DC system side, Z is the line wave impedance of the Berreman transmission line model, and R is the lumped resistance value of the line of the Berreman transmission line model; Based on the second processor, obtaining the AC system simulation result of the first processor, and determining the complete DC system simulation result of the power grid to be simulated according to the AC system simulation result and the DC system simulation result.

2. The method according to claim 1, wherein The decoupling the power grid to be simulated to obtain an AC power grid to be simulated and a DC power grid to be simulated includes: Constructing a Bergeyron transmission line model according to the power grid to be simulated; According to the Bergeyron transmission line model, obtaining the voltage and current on both sides of the Bergeyron transmission line model, where the voltage and current on both sides of the Bergeyron transmission line model include the voltage and current on the DC system side of the power grid to be simulated and the voltage and current on the AC system side; According to the Bergeyron transmission line model, decoupling the power grid to be simulated according to the voltage on the AC system side, the current on the AC system side, the voltage on the DC system side, and the current on the DC system side of the power grid to be simulated to obtain an AC power grid to be simulated and a DC power grid to be simulated.

3. The method according to claim 2, wherein The decoupling the power grid to be simulated according to the voltage on the AC system side, the current on the AC system side, the voltage on the DC system side, and the current on the DC system side of the power grid to be simulated to obtain an AC power grid to be simulated and a DC power grid to be simulated includes: Decoupling the power grid to be simulated through the following formula to determine the current value of the AC power grid to be simulated and the current value of the DC power grid to be simulated: i km (t) = 1 / (Z + R / 4)v k (t) + I k (t - τ) i mk (t) = 1 / (Z + R / 4)v m (t) + I m (t - τ) wherein, i km is the current value of the AC power grid to be simulated, v k is the voltage on the AC system side of the historical power grid to be simulated, I k is the current on the AC system side of the historical power grid to be simulated, i mk is the current value of the DC power grid to be simulated, v m is the voltage on the DC system side of the historical power grid to be simulated, I m is the current on the DC system side of the historical power grid to be simulated, Z is the line wave impedance of the Beroulli transmission line model, R is the lumped resistance value of the line of the Beroulli transmission line model, t is time, and τ is the line transmission delay of the Beroulli transmission line model.

4. The method according to any one of claims 1-3, characterized in that, Based on a first processor, using a preset electromagnetic transient simulation model to simulate the AC power grid to be simulated and determining an AC system simulation result; Based on a second processor, using a preset logic gate array simulation model to simulate the DC power grid to be simulated and determining a DC system simulation result, including: Based on the first processor, using the electromagnetic transient simulation model to simulate the AC power grid to be simulated according to a first preset simulation step; Based on the second processor, the logic gate array simulation model is used to simulate the DC power grid to be simulated according to a second preset simulation step length, where the first preset simulation step length is greater than the second preset simulation step length, and the first preset simulation step length is an integer multiple of the second preset simulation step length.

5. The method according to claim 4, characterized in that, Wherein, The AC system simulation result and the DC system simulation result both include simulation time, current and voltage information. Obtaining the DC system simulation result of the second processor based on the first processor, and determining the complete AC system simulation result of the power grid to be simulated according to the AC system simulation result and the DC system simulation result includes: Based on the first processor, obtain the DC system simulation result and read the simulation time of the DC system simulation result; If the simulation time of the DC system simulation result is the same as the simulation time of the current AC system simulation result of the first processor, then determine and store the current complete AC system simulation result of the power grid to be simulated according to the current and voltage information of the DC system simulation result and the current AC system simulation result; If the simulation time of the DC system simulation result is different from the simulation time of the current AC system simulation result of the first processor, then read the AC system simulation result with the same simulation time as the DC system simulation result, and determine and store the complete AC system simulation result of the power grid to be simulated at the simulation time according to the current and voltage information of the DC system simulation result and the AC system simulation result with the same simulation time; Every first preset time period, send the stored complete AC system simulation result of the power grid to be simulated to the second processor.

6. The method according to claim 5, wherein Obtaining the AC system simulation result of the first processor based on the second processor, and determining the complete DC system simulation result of the power grid to be simulated according to the AC system simulation result and the DC system simulation result, includes: Based on the second processor, obtain the AC system simulation result and read the simulation time of the AC system simulation result; If the simulation time of the AC system simulation result is the same as the simulation time of the current DC system simulation result of the second processor, then determine and store the current complete DC system simulation result of the power grid to be simulated according to the current and voltage information of the AC system simulation result and the current DC system simulation result; If the simulation time of the AC system simulation result is different from the simulation time of the current DC system simulation result of the second processor, then read the DC system simulation result with the same simulation time as the AC system simulation result, and determine and store the complete DC system simulation result of the power grid to be simulated at the simulation time according to the current and voltage information of the AC system simulation result and the DC system simulation result with the same simulation time; Every second preset time period, send the stored complete DC system simulation result of the power grid to be simulated to the first processor.

7. The method according to any one of claims 1 to 3, characterized in that, Determining the complete DC system simulation result of the power grid to be simulated according to the AC system simulation result and the DC system simulation result includes: Based on the second processor, obtaining the AC system simulation result at fixed time intervals; Performing interpolation processing on the AC system simulation result at a second preset simulation step length to obtain multiple interpolated AC system simulation results, where the interpolated AC system simulation results include the current on the interpolated AC system side and the voltage on the interpolated AC system side; Determining the complete DC system simulation result of the power grid to be simulated according to the multiple interpolated AC system simulation results and the DC system simulation result.

8. The method according to claim 7, characterized in that, Determining the complete DC system simulation result of the power grid to be simulated according to the multiple interpolated AC system simulation results and the DC system simulation result includes: Determining the complete DC system simulation result of the power grid to be simulated through the following formula: I m1 = (B1v m + B3i mk ) + (B2v k1 + B4i km1 ) Among them, I m1 is the complete DC system simulation result of the AC power grid to be simulated, v m is the voltage value of the history of the DC power grid to be simulated, i mk is the current value of the DC power grid to be simulated at present, v k1 is the voltage on the interpolated AC system side, i km1 is the current on the interpolated AC system side, Z is the line wave impedance of the Bergeyron transmission line model, and R is the line lumped resistance value of the Bergeyron transmission line model.

9. A simulation system for an AC / DC power system, characterized in that, The system includes: a host computer (10), a first processor (20), and a second processor (30), and the host computer (10), the first processor (20), and the second processor (30) are all interconnected, where The host computer (10) is configured to perform decoupling processing on the power grid to be simulated to obtain an AC power grid to be simulated and a DC power grid to be simulated; The first processor (20) is configured to simulate the AC power grid to be simulated by using a preset electromagnetic transient simulation model to determine the AC system simulation result; The second processor (30) is configured to simulate the DC power grid to be simulated by using a preset logic gate array simulation model to determine the DC system simulation result; The first processor (20) is further configured to obtain the DC system simulation result of the second processor (30), and based on the first processor, obtain the DC system simulation result at fixed time intervals; taking the average of the DC system simulation results within the fixed time interval to obtain an average DC system simulation result, where the average DC system simulation result includes the current on the average DC system side and the voltage on the average DC system side, and the fixed time interval is greater than the first preset simulation step length; determining the complete AC system simulation result of the power grid to be simulated through the following formula: I k1 = (B1v k + B3i km ) + (B2v m1 + B4i mk1 ) Among them, I k1 is the complete AC system simulation result of the AC power grid to be simulated, v k is the historical voltage value of the AC power grid to be simulated, i km is the current current value of the AC power grid to be simulated, v m1 is the voltage on the average DC system side, i mk1 is the current on the average DC system side, Z is the line wave impedance of the Bergeon transmission line model, and R is the line lumped resistance value of the Bergeon transmission line model; The second processor (30) is further configured to obtain the AC system simulation result of the first processor (20), and determine the complete DC system simulation result of the power grid to be simulated according to the AC system simulation result and the DC system simulation result.

10. The system according to claim 9, characterized in that, The second processor (30) includes: a network communication module, configured to send the DC system simulation result determined by the second processor (30) to the first processor (20) through Ethernet, and obtain the AC system simulation result determined by the first processor (20).

11. A computer device, comprising a memory and a processor, the memory storing a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 8.

12. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the steps of the method according to any one of claims 1 to 8.

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