A simulation method and device for short line decoupling in active distribution network

Abstract

The present invention relates to a simulation method and device for decoupling short lines in an active distribution network, comprising: calculating a distributed capacitance value added in the active distribution network according to a delay step length between adjacent computing cores in a core-divided parallel simulation of the active distribution network, wherein the added distributed capacitance value is connected in parallel to two ends of a short line; simulating and calculating a circuit between two ends of the short line with added distributed capacitance value, and exchanging electrical quantity data between two ends of the simulated short line, thereby realizing decoupling of short lines in the active distribution network and performing parallel simulation, thereby overcoming the inapplicability of the distribution network parallel simulation due to the too short length of the distribution network transmission line to a certain extent.

Description

Technical Field

[0001] The present invention relates to the field of active distribution network decoupling parallel simulation, and in particular to a simulation method and device for short line decoupling in an active distribution network. Background Art

[0002] Due to the addition of large-scale distributed power sources in the active distribution network, the network structure has become very complex and huge. The power electronic device model supporting the distributed power source has greatly limited the simulation speed of the large-scale active distribution network. In order to improve the simulation speed, it is necessary to partition the active distribution network and decouple it, put different areas into separate computing cores, and perform simulation calculations at the same time, so as to achieve multi-core parallel simulation. At the level of decoupling methods, network decoupling can be achieved through the Bergeron transformation of the transmission line model. The result of the transformation is to transform the coupling parts that originally have an electrical connection relationship into independent Bergeron equivalent circuits that have no electrical connection and influence each other in the form of controlled sources. The Bergeron equivalent circuit of the lossless line is as follows: Figure 1 shown.

[0003] The core-divided parallel simulation method of the distribution network is to decouple the originally coupled systems. The calculation results of each computing core need to be exchanged and transmitted according to a unified calculation step to ensure the convergence of the simulation results. The distribution network generally adopts power line carrier communication, so the medium for exchanging and transmitting the calculation result information is the transmission line. In order to ensure that each computing core can be given sufficient calculation completion time, the line length cannot be too short. There will be certain line length requirements. In the distribution network, the transmission line is generally short, generally 6-20km. If the calculation step Δt of each computing core is too short, it is possible that due to the short transmission line, the calculation result of the previous computing core will start to exchange and transmit information before the calculation result of the next computing core is obtained, which may lead to serious consequences such as reduced simulation accuracy or even divergent results. Summary of the invention

[0004] In view of the deficiencies of the prior art, the present invention provides a simulation method for short line decoupling in an active distribution network, the method comprising:

[0005] Calculating the added distributed capacitance value in the active distribution network according to the delay step length between adjacent computing cores in the active distribution network core-divided parallel simulation, wherein the added distributed capacitance value is connected in parallel to both ends of the short line;

[0006] The circuit between the two ends of the short line with the added distributed capacitance is simulated and calculated, and the electrical quantity data is exchanged between the two ends of the simulated short line to achieve short line decoupling in the active distribution network and parallel simulation.

[0007] Preferably, the calculation formula of the increased distributed capacitance value is as follows:

[0008]

[0009] Among them, Δt is the delay step, l is the length of the short line in the distribution network, L0 is the branch inductance connected in series with the short line, C0 is the existing distributed capacitance value connected in parallel with the short line, and C is the added distributed capacitance value connected in parallel with the short line.

[0010] Preferably, the electrical quantity data exchange between two ends of the short circuit being simulated includes:

[0011] Based on Thevenin's theorem, the computing cores at both ends are equivalent to port voltage and Thevenin equivalent impedance respectively;

[0012] The voltages at both ends of the short circuit in the active distribution network are calculated using the port voltage and the Thevenin equivalent impedance, and the voltages at both ends of the short circuit in the active distribution network are set to be equal, so as to obtain a calculation formula for the voltages at both ends of the short circuit in the active distribution network;

[0013] Arrange the calculation formula of the voltage at both ends of the short line in the active distribution network to obtain an equivalent model at both ends of the short line;

[0014] The current data at both ends of the short line in the active power distribution network are shared in an equivalent model at both ends of the short line.

[0015] Furthermore, the calculation formula for the voltage at both ends of the short line in the active distribution network is as follows:

[0016] u q (t-Δt)+Z c i q (t-Δt)=u p (t)-Z c i p (t)

[0017] Among them, the left side of the equal sign is the voltage at the upstream end of the short-circuit line in the active distribution network in the propagation direction of the electromagnetic traveling wave, and the right side of the equal sign is the voltage at the downstream end of the short-circuit line in the active distribution network in the propagation direction of the electromagnetic traveling wave;

[0018] u q (t-Δt) is the port voltage of the computing core at the upstream end of the short line in the active distribution network in the direction of electromagnetic wave propagation at t-Δt, i q (t-Δt) is the current flowing through the Thevenin equivalent impedance calculated by the computing core at the upstream end at t-Δt, u p (t) is the port voltage of the computing core at the downstream end of the short line in the active distribution network in the direction of electromagnetic wave propagation at time t, i p(t) is the current flowing through the Thevenin equivalent impedance calculated by the computing core at the downstream end at time t, t is the simulation time, Δt is the delay step, and Z c is the Thevenin equivalent impedance.

[0019] Furthermore, the equivalent model at both ends of the short line includes the following calculation formula:

[0020]

[0021] Among them, u q (t-Δt) is the port voltage of the computing core at the upstream end of the short line in the active distribution network in the direction of electromagnetic wave propagation at t-Δt, i q (t-Δt) is the current flowing through the Thevenin equivalent impedance calculated by the computing core at the upstream end at t-Δt, u p (t) is the port voltage of the computing core at the downstream end of the short line in the active distribution network in the direction of electromagnetic wave propagation at time t, i p (t) is the current flowing through the Thevenin equivalent impedance calculated by the computing core at the downstream end at time t, t is the simulation time, Δt is the delay step, and Z c is the Thevenin equivalent impedance.

[0022] Based on the same inventive concept, the present invention also provides a simulation device for short line decoupling in an active distribution network, comprising:

[0023] A calculation module, used for calculating the value of distributed capacitance added in parallel with the short line in the active distribution network according to the delay step between adjacent calculation cores in the active distribution network core-divided parallel simulation;

[0024] The decoupling module is used to use the computing cores at both ends of the short line with added distributed capacitance to perform simulation calculations, and to exchange electrical quantity data between the computing cores at both ends, so as to realize the decoupling of short lines in the active distribution network and perform parallel simulation.

[0025] Preferably, the calculation formula of the increased distributed capacitance value is as follows:

[0026]

[0027] Among them, Δt is the delay step, l is the length of the short line in the distribution network, L0 is the branch inductance connected in series with the short line, C0 is the existing distributed capacitance value connected in parallel with the short line, and C is the added distributed capacitance value connected in parallel with the short line.

[0028] Preferably, the decoupling module is specifically used for:

[0029] Based on Thevenin's theorem, the computing cores at both ends are equivalent to port voltage and Thevenin equivalent impedance respectively;

[0030] The voltages at both ends of the short circuit in the active distribution network are calculated using the port voltage and the Thevenin equivalent impedance, and the voltages at both ends of the short circuit in the active distribution network are set to be equal, so as to obtain a calculation formula for the voltages at both ends of the short circuit in the active distribution network;

[0031] Arrange the calculation formula of the voltage at both ends of the short line in the active distribution network to obtain an equivalent model at both ends of the short line;

[0032] The current data at both ends of the short line in the active power distribution network are shared in an equivalent model at both ends of the short line.

[0033] Furthermore, the calculation formula for the voltage at both ends of the short line in the active distribution network is as follows:

[0034] u q (t-Δt)+Z c i q (t-Δt)=u p (t)-Z c i p (t)

[0035] Among them, the left side of the equal sign is the voltage at the upstream end of the short-circuit line in the active distribution network in the propagation direction of the electromagnetic traveling wave, and the right side of the equal sign is the voltage at the downstream end of the short-circuit line in the active distribution network in the propagation direction of the electromagnetic traveling wave;

[0036] u q (t-Δt) is the port voltage of the computing core at the upstream end of the short line in the active distribution network in the direction of electromagnetic wave propagation at t-Δt, i q (t-Δt) is the current flowing through the Thevenin equivalent impedance calculated by the computing core at the upstream end at t-Δt, u p (t) is the port voltage of the computing core at the downstream end of the short line in the active distribution network in the direction of electromagnetic wave propagation at time t, i p (t) is the current flowing through the Thevenin equivalent impedance calculated by the computing core at the downstream end at time t, t is the simulation time, Δt is the delay step, and Z c is the Thevenin equivalent impedance.

[0037] Furthermore, the equivalent model at both ends of the short line includes the following calculation formula:

[0038]

[0039] Among them, u q (t-Δt) is the port voltage of the computing core at the upstream end of the short line in the active distribution network in the direction of electromagnetic wave propagation at t-Δt, i q(t-Δt) is the current flowing through the Thevenin equivalent impedance calculated by the computing core at the upstream end at t-Δt, u p (t) is the port voltage of the computing core at the downstream end of the short line in the active distribution network in the direction of electromagnetic wave propagation at time t, i p (t) is the current flowing through the Thevenin equivalent impedance calculated by the computing core at the downstream end at time t, t is the simulation time, Δt is the delay step, and Z c is the Thevenin equivalent impedance.

[0040] Compared with the closest prior art, the present invention has the following beneficial effects:

[0041] The present invention proposes a simulation method and device for decoupling short lines in an active distribution network, comprising: calculating the added distributed capacitance value in the active distribution network according to the delay step between adjacent computing cores in the core-divided parallel simulation of the active distribution network, wherein the added distributed capacitance value is connected in parallel to both ends of the short line; simulating and calculating the circuit between the two ends of the short line with the added distributed capacitance value, and exchanging electrical quantity data between the two ends of the simulated short line, so as to realize decoupling of short lines in the active distribution network and perform parallel simulation; the present invention improves the traditional distributed parameter long line decoupling method, and proposes a characteristic line-based short line decoupling simulation method, that is, through the distributed capacitance method, the traveling wave transmission time is increased, thereby overcoming the inapplicability of long distributed parameter lines in the parallel simulation of the distribution network to a certain extent. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 It is a Bergeron equivalent circuit diagram of a lossless line provided by the present invention;

[0043] Figure 2 It is a flow chart of a simulation method for short line decoupling in an active distribution network provided by the present invention;

[0044] Figure 3 This is a short circuit equivalent calculation model diagram considering distributed capacitance provided by the present invention;

[0045] Figure 4 This is an equivalent model diagram of two ends of a short circuit considering distributed capacitance provided by the present invention;

[0046] Figure 5 It is the IEEE33 node standard example characteristic line short line partition decoupling diagram provided by the present invention;

[0047] Figure 6 It is a local diagram of the voltage at the photovoltaic access point of the IEEE33 system three-phase fault event provided by the present invention;

[0048] Figure 7It is a partial diagram of photovoltaic output current in a three-phase fault event of the IEEE33 system provided by the present invention;

[0049] Figure 8 is a photovoltaic injection current error diagram of a three-phase fault event in an IEEE33 system provided by the present invention;

[0050] Fig. 9 It is a voltage error diagram of photovoltaic access point in a three-phase fault event of IEEE33 system provided by the present invention;

[0051] Fig.10 This is a diagram of a simulation device for short line decoupling in an active distribution network provided by the present invention. DETAILED DESCRIPTION

[0052] The specific implementation modes of the present invention will be further described in detail below in conjunction with the accompanying drawings.

[0053] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0054] Embodiment 1:

[0055] The present invention provides a simulation method for short line decoupling in an active distribution network, such as Figure 2 As shown, including:

[0056] Step 1: Calculate the added distributed capacitance value in the active distribution network according to the delay step between adjacent computing cores in the active distribution network core-divided parallel simulation, and the added distributed capacitance value is connected in parallel to both ends of the short line;

[0057] Step 2: Simulate the circuit between the two ends of the short line with the added distributed capacitance value, and exchange electrical quantity data between the two ends of the simulated short line to achieve short line decoupling in the active distribution network and perform parallel simulation.

[0058] In view of the situation that the line length in the distribution network does not meet the information transmission time difference requirements of the distribution network core parallel simulation, there are only two improvement methods. One is to increase the line length to ensure that the information transmission time difference is sufficient, but this has no practical significance. The line length of the actual distribution network itself cannot be lengthened; the other is to increase the information transmission time, that is, to ensure that the calculation results of the previous calculation core are delivered in place after the calculation of the next calculation core is completed.

[0059] Since information in power line carrier communication is transmitted in the form of electromagnetic waves, the present invention increases the traveling wave transmission time by adding distributed capacitors, thereby overcoming the inapplicability of the distribution network parallel simulation due to the short length of the distribution network transmission line to a certain extent.

[0060] In step 1, the calculation formula of the added distributed capacitance value is as follows:

[0061]

[0062] Among them, Δt is the delay step, l is the length of the short line in the distribution network, L0 is the branch inductance connected in series with the short line, C0 is the existing distributed capacitance value connected in parallel with the short line, and C is the added distributed capacitance value connected in parallel with the short line.

[0063] Step 2 specifically includes:

[0064] In this embodiment, the short line equivalent calculation model of distributed capacitance is considered, such as Figure 3 As shown, x is the line length, dx is the line length microelement, i is the current flowing in the series branch, L0 is the series branch inductance, R0 is the series branch resistance, C0 is the parallel distributed capacitance, and U0 is the voltage across the series branch (the voltage drop in the middle is a function of the line length microelement and can be ignored, so the voltages at both ends can be set to the same value). is the partial derivative of current with respect to line length, is the partial derivative of voltage with respect to line length.

[0065] The wave equation is:

[0066]

[0067]

[0068] Assume that the propagation speed of the traveling wave is v and the characteristic impedance during the traveling wave transmission is Z c According to the principle of traveling wave propagation:

[0069]

[0070]

[0071] According to the fixed-step parallel simulation principle, there will be a step delay Δt between cores in multi-core parallelism. The following is an analysis of the wave equation using two cores as the object. Assuming that the traveling wave propagates forward at a speed v, f1(x-vΔt) is the minimum time for the traveling wave to propagate forward, that is, the solution of one step propagation time. Similarly, f2(x+vΔt) is the minimum time for the traveling wave to propagate backward, that is, the solution of one step propagation time. The voltage and current equations are used to describe the solution as follows:

[0072]

[0073] The reason why the expression of u(x,t) is the subtraction of f1(x-vΔt) and f2(x+vΔt) and then multiplication by Zc is that if we understand the current as a traveling wave, then the relationship between the voltage traveling wave propagated one step forward and the current traveling wave propagated one step forward is:

[0074] u(x-vΔt)=Z c f1(x-vΔt)

[0075] Similarly, the relationship between the voltage traveling wave propagating one step forward and the current traveling wave propagating one step forward is:

[0076] u(x+vΔt)=-Z c f2(x+vΔt)

[0077] Then the voltage value at a certain moment and a certain position can also be considered as the sum of the solutions propagated forward and backward by one step, that is, the sum of the two, that is,

[0078] u(x,t)=u(x-vΔt)+u(x+vΔt)

[0079] Because the line is uniform and lossless, the electromagnetic wave does not distort or attenuate when it propagates forward along the line. When the observer moves along the positive x direction at a speed v with the forward wave (i.e. x-νt = constant), the value i(x, t)Z calculated based on the instantaneous voltage value u(x, t) and current value i(x, t) observed at his position x at time t is c -u(x,t) always remains unchanged, equal to twice the size of the previous current wave, that is, 2f2(x+vΔt). This situation is true from the beginning to the end of the line. From the perspective of the backward propagation of the traveling wave, both sides of the current equation in the above formula are multiplied by Z c And subtract it from the voltage equation as follows:

[0080] i(x,t)Z c -u(x,t)=2f2(x+vΔt)Z c

[0081] If the distance of the distributed parameter line, i.e. the short line in the active distribution network, is set to l, whether it is propagating in the forward direction or the backward direction of the traveling wave, the propagation time can be considered constant, that is, x+vΔt and x-vΔt are constants, then the transmission time from the beginning to the end is:

[0082]

[0083] Each computing core is equivalent to a port voltage u and a Thevenin equivalent impedance Zc using Thevenin, and the port voltage u of the previous computing core at the previous step is i (t-Δt) plus the voltage drop Z of the Thevenin equivalent impedance of this core c i i (t-Δt) is the calculation result of this core and is passed to the next calculation core. This result must be equal to the port voltage u at the next step. j (t) minus the voltage drop Z of the Thevenin equivalent impedance of this core c i j (t), thereby realizing the transmission of calculation results between various computing cores, so that the calculation process conforms to the electrical connection relationship. It is also from this formula that the equivalent model of the two ends of the distributed parameter line is obtained. It can be found that there is no direct connection between the two ends of the power line, but through the current data sharing, the electrical quantities at both ends are exchanged, thereby realizing parallel simulation. If the observer starts from node i at time (t-Δt), and reaches node j at time t, the voltage at both ends of the distributed parameter line is:

[0084] u i (t-Δt)+Z c i i (t-Δt)=u j (t)-Z c i j (t)

[0085] The negative sign on the right side of the equation indicates that the traveling wave propagates forward, and t-Δt indicates that the CPU operation time lags behind by one step, that is, within the operation time of this step, the data of the cutting point is the data of the previous step of the core connected to it.

[0086] After finishing, we can get:

[0087]

[0088] Among them, the above formula is composed of i i (t-Δt) can be deduced in reverse as follows:

[0089]

[0090] in, That is, the following formula

[0091]

[0092] In this embodiment, the equivalent model of the two ends of the short line with distributed capacitance is considered, such as Figure 4 As shown in FIG. 1 , it is an equivalent model of the two ends of a distributed parameter line. There is no direct connection between the two ends. The electrical quantities at the two ends are exchanged by sharing the current data.

[0093] The above method is used to realize the decoupling of short-circuit lines in the active distribution network. The two computing cores simulate the two ends of the short-circuit lines in the active distribution network respectively, and the electrical quantities at both ends are exchanged by sharing the current data, thereby realizing parallel simulation.

[0094] Embodiment 2:

[0095] The present invention provides a preferred embodiment of a simulation method for short line decoupling in an active distribution network, such as Figure 5 In the IEEE33 node system shown in the figure, a single distributed photovoltaic is connected to node 9, and the distribution network is divided between nodes 8 and 9. Since nodes 8 and 9 are connected and the line between them is short, the characteristic line short line decoupling method is adopted.

[0096] The IEEE33 node system is decoupled from nodes 8 and 9 and divided into two parts, which are placed in 1#CPU and 2#CPU for split-core parallel simulation. The transient event is set to a three-phase short circuit fault at node 17, and the distributed photovoltaic output power will inevitably change accordingly. At the same time, a serial simulation control group is set up, that is, the entire IEEE33 node system is placed in the same computing core for serial simulation.

[0097] In this embodiment, the local voltage of the photovoltaic access point in the event of a three-phase fault in the IEEE33 system is as follows: Figure 6 shown.

[0098] In this embodiment, the photovoltaic output current of the IEEE33 system three-phase fault event is as follows: Figure 7 shown.

[0099] In this embodiment, the photovoltaic injection current error of the IEEE33 system three-phase fault event is as follows: Figure 8 shown.

[0100] In this embodiment, the voltage error of the photovoltaic access point in the IEEE33 system three-phase fault event is as follows: Fig. 9 shown.

[0101] Judging from the running results, the transient simulation results using the short line decoupling method are basically consistent with the traditional serial simulation results. However, from the analysis of the effect diagram after error amplification, it can be seen that there will be a sudden increase in error at the switching moment of the transient process. It can be inferred that at the moment of transient switching, the computing resources suddenly increase, resulting in a sudden increase in inter-core communication volume. At the same time, the increased distributed capacitance will also cause certain interference to the information transmission, which will ultimately affect the correctness of the simulation results.

[0102] Embodiment 3:

[0103] Based on the same inventive concept, the present invention also provides a simulation device for short line decoupling in an active distribution network, such as Fig.10 As shown, including:

[0104] A calculation module, used for calculating the value of distributed capacitance added in parallel with the short line in the active distribution network according to the delay step between adjacent calculation cores in the active distribution network core-divided parallel simulation;

[0105] The decoupling module is used to use the computing cores at both ends of the short line with added distributed capacitance to perform simulation calculations, and to exchange electrical quantity data between the computing cores at both ends, so as to realize the decoupling of short lines in the active distribution network and perform parallel simulation.

[0106] The calculation formula of the increased distributed capacitance value is as follows:

[0107]

[0108] Among them, Δt is the delay step, l is the length of the short line in the distribution network, L0 is the branch inductance connected in series with the short line, C0 is the existing distributed capacitance value connected in parallel with the short line, and C is the added distributed capacitance value connected in parallel with the short line.

[0109] The decoupling module is specifically used for:

[0110] Based on Thevenin's theorem, the computing cores at both ends are equivalent to port voltage and Thevenin equivalent impedance respectively;

[0111] The voltages at both ends of the short circuit in the active distribution network are calculated using the port voltage and the Thevenin equivalent impedance, and the voltages at both ends of the short circuit in the active distribution network are set to be equal, so as to obtain a calculation formula for the voltages at both ends of the short circuit in the active distribution network;

[0112] Arrange the calculation formula of the voltage at both ends of the short line in the active distribution network to obtain an equivalent model at both ends of the short line;

[0113] The current data at both ends of the short line in the active power distribution network are shared in an equivalent model at both ends of the short line.

[0114] The calculation formula for the voltage across the short line in the active distribution network is as follows:

[0115] u q (t-Δt)+Z c i q (t-Δt)=u p (t)-Z c i p (t)

[0116] Among them, the left side of the equal sign is the voltage at the upstream end of the short-circuit line in the active distribution network in the propagation direction of the electromagnetic traveling wave, and the right side of the equal sign is the voltage at the downstream end of the short-circuit line in the active distribution network in the propagation direction of the electromagnetic traveling wave;

[0117] u q (t-Δt) is the port voltage of the computing core at the upstream end of the short line in the active distribution network in the direction of electromagnetic wave propagation at t-Δt, i q (t-Δt) is the current flowing through the Thevenin equivalent impedance calculated by the computing core at the upstream end at t-Δt, u p (t) is the port voltage of the computing core at the downstream end of the short line in the active distribution network in the direction of electromagnetic wave propagation at time t, i p (t) is the current flowing through the Thevenin equivalent impedance calculated by the computing core at the downstream end at time t, t is the simulation time, Δt is the delay step, and Z c is the Thevenin equivalent impedance.

[0118] The equivalent model of both ends of the short line includes the following calculation formula:

[0119]

[0120] Among them, u q (t-Δt) is the port voltage of the computing core at the upstream end of the short line in the active distribution network in the direction of electromagnetic wave propagation at t-Δt, i q (t-Δt) is the current flowing through the Thevenin equivalent impedance calculated by the computing core at the upstream end at t-Δt, u p (t) is the port voltage of the computing core at the downstream end of the short line in the active distribution network in the direction of electromagnetic wave propagation at time t, i p (t) is the current flowing through the Thevenin equivalent impedance calculated by the computing core at the downstream end at time t, t is the simulation time, Δt is the delay step, and Z c is the Thevenin equivalent impedance.

[0121] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0122] The present invention is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of the processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0123] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0124] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0125] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A simulation method for short line decoupling in an active distribution network, characterized in that: include: Calculating the added distributed capacitance value in the active distribution network according to the delay step length between adjacent computing cores in the active distribution network core-divided parallel simulation, wherein the added distributed capacitance value is connected in parallel to both ends of the short line; The circuit between the two ends of the short line with the added distributed capacitance is simulated and the electrical quantity data is exchanged between the two ends of the simulated short line, so as to realize the decoupling of the short lines in the active distribution network and perform parallel simulation. The calculation formula of the increased distributed capacitance value is as follows: Wherein, Δt is the delay step, l is the length of the short line in the distribution network, L0 is the branch inductance connected in series with the short line, C0 is the existing distributed capacitance value connected in parallel with the short line, and C is the added distributed capacitance value connected in parallel with the short line; The electrical quantity data exchange between two ends of the short line being simulated includes: Based on Thevenin's theorem, the computing cores at both ends are equivalent to port voltage and Thevenin equivalent impedance respectively; The voltages at both ends of the short circuit in the active distribution network are calculated using the port voltage and the Thevenin equivalent impedance, and the voltages at both ends of the short circuit in the active distribution network are set to be equal, so as to obtain a calculation formula for the voltages at both ends of the short circuit in the active distribution network; Arrange the calculation formula of the voltage at both ends of the short line in the active distribution network to obtain an equivalent model at both ends of the short line; The current data at both ends of the short line in the active power distribution network are shared in an equivalent model at both ends of the short line.

2. The method according to claim 1, characterized in that: The calculation formula for the voltage across the short line in the active distribution network is as follows: u q (t-Δt)+Z c i q (t-Δt)=u p (t)-Z c i p (t) Among them, the left side of the equal sign is the voltage at the upstream end of the short-circuit line in the active distribution network in the propagation direction of the electromagnetic traveling wave, and the right side of the equal sign is the voltage at the downstream end of the short-circuit line in the active distribution network in the propagation direction of the electromagnetic traveling wave; u q (t-Δt) is the port voltage of the computing core at the upstream end of the short line in the active distribution network in the direction of electromagnetic wave propagation at t-Δt, i q (t-Δt) is the current flowing through the Thevenin equivalent impedance calculated by the computing core at the upstream end at t-Δt, u p (t) is the port voltage of the computing core at the downstream end of the short line in the active distribution network in the direction of electromagnetic wave propagation at time t, i p (t) is the current flowing through the Thevenin equivalent impedance calculated by the computing core at the downstream end at time t, t is the simulation time, Δt is the delay step, and Z c is the Thevenin equivalent impedance.

3. The method according to claim 1, characterized in that: The equivalent model of both ends of the short line includes the following calculation formula: Among them, u q (t-Δt) is the port voltage of the computing core at the upstream end of the short line in the active distribution network in the direction of electromagnetic wave propagation at t-Δt, i q (t-Δt) is the current flowing through the Thevenin equivalent impedance calculated by the computing core at the upstream end at t-Δt, u p (t) is the port voltage of the computing core at the downstream end of the short line in the active distribution network in the direction of electromagnetic wave propagation at time t, i p (t) is the current flowing through the Thevenin equivalent impedance calculated by the computing core at the downstream end at time t, t is the simulation time, Δt is the delay step, and Z c is the Thevenin equivalent impedance.

4. A simulation device for short line decoupling in an active distribution network, characterized in that: include: A calculation module, used for calculating the value of distributed capacitance added in parallel with the short line in the active distribution network according to the delay step between adjacent calculation cores in the active distribution network core-divided parallel simulation; A decoupling module is used to use computing cores at both ends of a short line with added distributed capacitance to perform simulation calculations, and to exchange electrical quantity data between the computing cores at both ends, so as to achieve short line decoupling and parallel simulation in an active distribution network; The calculation formula of the increased distributed capacitance value is as follows: Wherein, Δt is the delay step, l is the length of the short line in the distribution network, L0 is the branch inductance connected in series with the short line, C0 is the existing distributed capacitance value connected in parallel with the short line, and C is the added distributed capacitance value connected in parallel with the short line; The decoupling module is specifically used for: Based on Thevenin's theorem, the computing cores at both ends are equivalent to port voltage and Thevenin equivalent impedance respectively; The voltages at both ends of the short circuit in the active distribution network are calculated using the port voltage and the Thevenin equivalent impedance, and the voltages at both ends of the short circuit in the active distribution network are set to be equal, so as to obtain a calculation formula for the voltages at both ends of the short circuit in the active distribution network; Arrange the calculation formula of the voltage at both ends of the short line in the active distribution network to obtain an equivalent model at both ends of the short line; The current data at both ends of the short line in the active power distribution network are shared in an equivalent model at both ends of the short line.

5. The device according to claim 4, characterized in that: The calculation formula for the voltage across the short line in the active distribution network is as follows: u q (t-Δt)+Z c i q (t-Δt)=u p (t)-Z c i p (t) Among them, the left side of the equal sign is the voltage at the upstream end of the short-circuit line in the active distribution network in the propagation direction of the electromagnetic traveling wave, and the right side of the equal sign is the voltage at the downstream end of the short-circuit line in the active distribution network in the propagation direction of the electromagnetic traveling wave; u q (t-Δt) is the port voltage of the computing core at the upstream end of the short line in the active distribution network in the direction of electromagnetic wave propagation at t-Δt, i q (t-Δt) is the current flowing through the Thevenin equivalent impedance calculated by the computing core at the upstream end at t-Δt, u p (t) is the port voltage of the computing core at the downstream end of the short line in the active distribution network in the direction of electromagnetic wave propagation at time t, i p (t) is the current flowing through the Thevenin equivalent impedance calculated by the computing core at the downstream end at time t, t is the simulation time, Δt is the delay step, and Z c is the Thevenin equivalent impedance.

6. The device according to claim 4, characterized in that: The equivalent model of both ends of the short line includes the following calculation formula: Among them, u q (t-Δt) is the port voltage of the computing core at the upstream end of the short line in the active distribution network in the direction of electromagnetic wave propagation at t-Δt, i q (t-Δt) is the current flowing through the Thevenin equivalent impedance calculated by the computing core at the upstream end at t-Δt, u p (t) is the port voltage of the computing core at the downstream end of the short line in the active distribution network in the direction of electromagnetic wave propagation at time t, i p (t) is the current flowing through the Thevenin equivalent impedance calculated by the computing core at the downstream end at time t, t is the simulation time, Δt is the delay step, and Z c is the Thevenin equivalent impedance.

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