A continuous power flow calculation method and system considering generator dynamics

Abstract

The present invention discloses a method and system for continuous power flow calculation that takes into account the dynamics of generators, comprising: obtaining the current power of each node in the power system; performing power flow calculation based on the current power to determine the current operating data of each node; determining an improved Jacobian matrix based on the current operating data, and calculating the current minimum characteristic root of the improved Jacobian matrix; when the current minimum characteristic root is a preset threshold or the product of the current minimum characteristic root and the minimum characteristic root obtained by the last power flow calculation is a negative number, determining that the power system has reached a static voltage stability limit. The method of the present invention can take into account the dynamic characteristics of the generator in the continuous power flow calculation, is suitable for a high-proportion new energy power system, and can provide a more accurate analysis tool for the static voltage stability analysis of the power system, thereby obtaining a more accurate static voltage stability limit power, thereby improving the accuracy of the power grid security and stability analysis and the operational safety.

Description

Technical Field

[0001] The present invention relates to the technical field of power system operation, and more particularly to a method and system for calculating continuous power flow considering generator dynamics. Background Art

[0002] Static voltage stability analysis of power systems investigates whether the system voltage will experience non-periodic instability under small disturbances. Because the model used in static stability analysis is relatively simple, it reflects the impact of network structure, parameters, and operating conditions on the system's stability under small disturbances. It also utilizes mature and simple methods to calculate the system's static stability power limit, thereby determining the system's static safe and stable operating range. This method has been widely used in the actual operation of power systems, including analysis of the system's power supply limit to load centers and the maximum DC power that can be carried by the AC system to which the DC is connected.

[0003] The continuation power flow method is a commonly used approach for static voltage stability analysis of complex systems. This method continuously deteriorates the system's operating conditions according to a given pattern, performing power flow calculations and analysis for each condition until the static stability limit criterion is met. The resulting condition is then considered the system's static stability limit. The continuation power flow method essentially searches for critical conditions where a power flow solution exists, based on power flow calculations. Traditional continuation power flow methods do not consider the dynamic characteristics of individual components in the system.

[0004] As the proportion of renewable energy generation in power systems continues to increase, the applicability of traditional continuation power flow methods continues to decline. Therefore, a continuation power flow calculation method and system that considers generator dynamics is needed. Summary of the Invention

[0005] The present invention proposes a continuous power flow calculation method and system that considers the dynamics of generators to solve the problem that the traditional continuous power flow method cannot be applied to power systems with a high proportion of renewable energy because it does not consider the dynamic characteristics of each component in the system.

[0006] In order to solve the above problem, according to one aspect of the present invention, a method for calculating a continuous power flow taking into account the dynamics of a generator is provided, the method comprising:

[0007] Get the current power of each node in the power system;

[0008] Perform power flow calculation based on current power to determine the current operating data of each node;

[0009] Determine an improved Jacobian matrix according to current operating data, and calculate a current minimum eigenvalue of the improved Jacobian matrix;

[0010] When the current minimum characteristic root is a preset threshold or the product of the current minimum characteristic root and the minimum characteristic root obtained by the last power flow calculation is a negative number, it is determined that the power system has reached the static voltage stability limit.

[0011] Preferably, determining the improved Jacobian matrix according to the current operating data comprises:

[0012]

[0013]

[0014]

[0015] Wherein, J is the improved Jacobian matrix; H, N, M, and L are the active-phase angle block matrix, the active-voltage block matrix, the reactive-phase angle block matrix, and the reactive-voltage block matrix, respectively. The block matrices H, N, M, and L are all m×m matrices, where m is the number of nodes; H ij 、N ij 、M ij and L ij are the off-diagonal elements of the block matrices H, N, M, and L, respectively, i≠j, H ii 、N ii 、M ii , L ii are the diagonal elements of the block matrices H, N, M, and L respectively; i = 1, 2, ..., m, j∈i represents all nodes j connected to node i; U i is the voltage at node i; θ i is the phase angle of node i; P Gi and Q Gi are the active power and reactive power injected by the generator of node i, respectively. For non-generator nodes, P Gi and Q Gi The value of G is zero; ij and B ij are the real and imaginary parts of the elements in the i-th row and j-th column of the node admittance matrix respectively; θ ij is the phase angle difference between node i and node j.

[0016] Preferably, if the node i is a synchronous generator node, the dynamic differential term is calculated in the following manner, including:

[0017]

[0018] If node i is a new energy generator node, the dynamic differential term is calculated using the following method, including:

[0019]

[0020] Among them, Xdi ' is the transient reactance when node i is a synchronous generator node, E i ' is the internal potential when node i is a synchronous generator node, θ δi is the power angle when node i is a synchronous generator node; k P is the proportional coefficient of the AC voltage control link when node i is a new energy generator node.

[0021] Preferably, the method further comprises:

[0022] When the power system has not reached the static voltage stability limit, the power of each node in the power system is adjusted according to the preset strategy and recalculated until the current minimum characteristic root is a preset threshold or the product of the current minimum characteristic root and the minimum characteristic root obtained by the last flow calculation is a negative number, and it is determined that the power system has reached the static voltage stability limit.

[0023] Preferably, the nodes include: load nodes, synchronous generator nodes and / or new energy generator nodes.

[0024] According to one aspect of the present invention, a continuous power flow calculation system considering generator dynamics is provided, the system comprising:

[0025] A power acquisition unit, used to obtain the current power of each node in the power system;

[0026] The power flow calculation unit is used to perform power flow calculation based on the current power and determine the current operating data of each node;

[0027] a characteristic root determination unit, configured to determine an improved Jacobian matrix according to current operating data, and calculate a current minimum characteristic root of the improved Jacobian matrix;

[0028] The static voltage stability limit determination unit is used to determine that the power system has reached the static voltage stability limit when the current minimum characteristic root is a preset threshold or the product of the current minimum characteristic root and the minimum characteristic root obtained by the last power flow calculation is a negative number.

[0029] Preferably, the power flow calculation unit determines the improved Jacobian matrix according to the current operating data, including:

[0030]

[0031]

[0032]

[0033] Wherein, J is the improved Jacobian matrix; H, N, M, and L are the active-phase angle block matrix, the active-voltage block matrix, the reactive-phase angle block matrix, and the reactive-voltage block matrix, respectively. The block matrices H, N, M, and L are all m×m matrices, where m is the number of nodes; H ij 、N ij 、M ij and L ij are the off-diagonal elements of the block matrices H, N, M, and L, respectively, i≠j, H ii 、N ii 、M ii , L ii are the diagonal elements of the block matrices H, N, M, and L respectively; i = 1, 2, ..., m, j∈i represents all nodes j connected to node i; U i is the voltage at node i; θ i is the phase angle of node i; P Gi and Q Gi are the active power and reactive power injected by the generator of node i, respectively. For non-generator nodes, P Gi and Q Gi The value of G is zero; ij and B ij are the real and imaginary parts of the elements in the i-th row and j-th column of the node admittance matrix respectively; θ ij is the phase angle difference between node i and node j.

[0034] Preferably, in the power flow calculation unit, if the node i is a synchronous generator node, the dynamic differential term is calculated in the following manner, including:

[0035]

[0036] If node i is a new energy generator node, the dynamic differential term is calculated using the following method, including:

[0037]

[0038] Among them, X di ' is the transient reactance when node i is a synchronous generator node, E i ' is the internal potential when node i is a synchronous generator node, θ δi is the power angle when node i is a synchronous generator node; k P is the proportional coefficient of the AC voltage control link when node i is a new energy generator node.

[0039] Preferably, the system further comprises:

[0040] An updating unit is used to adjust the power of each node in the power system according to a preset strategy when the power system has not reached the static voltage stability limit, and enter the power acquisition unit for recalculation until the current minimum characteristic root is a preset threshold or the product of the current minimum characteristic root and the minimum characteristic root obtained by the last power flow calculation is a negative number, thereby determining that the power system has reached the static voltage stability limit.

[0041] Preferably, in the power acquisition unit, the nodes include: load nodes, synchronous generator nodes and / or new energy generator nodes.

[0042] The present invention provides a method and system for continuous power flow calculation that takes into account the dynamics of generators, including: obtaining the current power of each node in the power system; performing power flow calculation based on the current power to determine the current operating data of each node; determining an improved Jacobian matrix based on the current operating data, and calculating the current minimum characteristic root of the improved Jacobian matrix; when the current minimum characteristic root is a preset threshold or the product of the current minimum characteristic root and the minimum characteristic root obtained by the last power flow calculation is a negative number, determining that the power system has reached a static voltage stability limit. The method of the present invention can take into account the dynamic characteristics of the generator in the continuous power flow calculation, is suitable for high-proportion new energy power systems, and can provide a more accurate analysis tool for the static voltage stability analysis of the power system, thereby obtaining a more accurate static voltage stability limit power, thereby improving the accuracy of the power grid security and stability analysis and operational safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] A more complete understanding of exemplary embodiments of the present invention may be obtained by referring to the following drawings:

[0044] Figure 1 Flow chart of a continuous power flow calculation method 100 considering generator dynamics according to an embodiment of the present invention;

[0045] Figure 2 FIG. 2 is a schematic structural diagram of a continuous power flow calculation system 200 considering generator dynamics according to an embodiment of the present invention. DETAILED DESCRIPTION

[0046] Exemplary embodiments of the present invention will now be described with reference to the accompanying drawings. However, the present invention may be embodied in many different forms and is not limited to the embodiments described herein. These embodiments are provided to provide a thorough and complete disclosure of the present invention and to fully convey the scope of the present invention to those skilled in the art. The terminology used in the exemplary embodiments shown in the accompanying drawings is not intended to limit the present invention. In the accompanying drawings, identical elements are denoted by the same reference numerals.

[0047] Unless otherwise specified, the terms used herein (including technical terms) have the meanings commonly understood by those skilled in the art. In addition, it is understood that terms defined in commonly used dictionaries should be understood to have the same meanings as those in the context of the relevant fields, and should not be understood as idealized or overly formal meanings.

[0048] Figure 1 FIG. 1 is a flow chart of a continuous power flow calculation method 100 considering generator dynamics according to an embodiment of the present invention. Figure 1 As shown, the continuous power flow calculation method considering generator dynamics provided by an embodiment of the present invention can take into account the dynamic characteristics of generators in the continuous power flow calculation. It is suitable for power systems with a high proportion of new energy. It can provide a more accurate analysis tool for static voltage stability analysis of power systems, thereby obtaining a more accurate static voltage stability limit power, improving the accuracy of power grid security and stability analysis and operational safety. The continuous power flow calculation method 100 considering generator dynamics provided by an embodiment of the present invention begins with step 101, in which the current power of each node in the power system is obtained.

[0049] Preferably, the nodes include: load nodes, synchronous generator nodes and / or new energy generator nodes.

[0050] In step 102, power flow calculation is performed based on the current power to determine the current operating data of each node.

[0051] In step 103, an improved Jacobian matrix is ​​determined according to the current operating data, and the current minimum eigenvalue of the improved Jacobian matrix is ​​calculated.

[0052] Preferably, determining the improved Jacobian matrix according to the current operating data comprises:

[0053]

[0054]

[0055]

[0056] Wherein, J is the improved Jacobian matrix; H, N, M, and L are the active-phase angle block matrix, the active-voltage block matrix, the reactive-phase angle block matrix, and the reactive-voltage block matrix, respectively. The block matrices H, N, M, and L are all m×m matrices, where m is the number of nodes; H ij 、N ij 、M ij and L ij are the off-diagonal elements of the block matrices H, N, M, and L, respectively, i≠j, H ii 、N ii、M ii , L ii are the diagonal elements of the block matrices H, N, M, and L respectively; i = 1, 2, ..., m, j∈i represents all nodes j connected to node i; U i is the voltage at node i; θ i is the phase angle of node i; P Gi and Q Gi are the active power and reactive power injected by the generator of node i, respectively. For non-generator nodes, P Gi and Q Gi The value of G is zero; ij and B ij are the real and imaginary parts of the elements in the i-th row and j-th column of the node admittance matrix respectively; θ ij is the phase angle difference between node i and node j.

[0057] Preferably, if the node i is a synchronous generator node, the dynamic differential term is calculated in the following manner, including:

[0058]

[0059] If node i is a new energy generator node, the dynamic differential term is calculated using the following method, including:

[0060]

[0061] Among them, X di ' is the transient reactance when node i is a synchronous generator node, E i ' is the internal potential when node i is a synchronous generator node, θ δi is the power angle when node i is a synchronous generator node; k P is the proportional coefficient of the AC voltage control link when node i is a new energy generator node.

[0062] In the embodiment of the present invention, the current power of each node in the power system is obtained, and the power flow calculation is performed based on the obtained power to obtain the voltage U of each node. i and phase angle θ i , and the internal potential E of the traditional synchronous generator i ' and power angle θ δi Then, according to the voltage U of each node i and phase angle θ i , and the internal potential E of the traditional synchronous generator i ' and power angle θ δiAn improved Jacobian matrix is ​​determined, and the current minimum eigenvalue of the improved Jacobian matrix is ​​calculated. A node in the present invention generally refers to a busbar node in a power system network, which can be a load node, a synchronous generator node, or a new energy generator node, or any combination of the above nodes.

[0063] The improved Jacobian matrix of the embodiment of the present invention is different from the Jacobian matrix used in the traditional continuous power flow method in that the differential terms of the dynamic characteristics of the generator nodes are added to the elements corresponding to the nodes of the generator.

[0064] The improved Jacobian matrix J provided by the embodiment of the present invention is specifically as follows:

[0065]

[0066] Among them, H, N, M, and L are the active-phase angle block matrix, active-voltage block matrix, reactive-phase angle block matrix, and reactive-voltage block matrix, respectively. The block matrices H, N, M, and L are all m×m matrices, where m is the number of nodes.

[0067] The off-diagonal elements H of the block matrices H, N, M, and L ij 、N ij 、M ij , L ij (i≠j) is calculated using the following formula:

[0068]

[0069] Diagonal element H ii 、N ii 、M ii , L ii The calculation formula is as follows:

[0070]

[0071] Where i = 1, 2, ..., m, j∈i represents all nodes j connected to node i, U i is the voltage at node i, P Gi , Q Gi are the active power and reactive power injected by the generator of node i (for non-generator nodes, their values ​​are zero), G ij 、B ij are the real and imaginary parts of the elements in the i-th row and j-th column of the node admittance matrix, θ ij is the phase angle difference between nodes i and j.

[0072] For the dynamic differential term of the generator node in the above formula, if the node i is a traditional synchronous generator node, the specific calculation formula is:

[0073]

[0074] If the node i is a new energy generator node, the specific calculation formula is:

[0075]

[0076] Among them, X di ' is the transient reactance when node i is a synchronous generator node, E i ' is the internal potential when node i is a synchronous generator node, θ δi is the power angle when node i is a synchronous generator node; k P is the proportional coefficient of the AC voltage control link when node i is a new energy generator node.

[0077] In step 104 , when the current minimum characteristic root is a preset threshold or the product of the current minimum characteristic root and the minimum characteristic root obtained by the last power flow calculation is a negative number, it is determined that the power system has reached the static voltage stability limit.

[0078] Preferably, the method further comprises:

[0079] When the power system has not reached the static voltage stability limit, the power of each node in the power system is adjusted according to the preset strategy and recalculated until the current minimum characteristic root is a preset threshold or the product of the current minimum characteristic root and the minimum characteristic root obtained by the last flow calculation is a negative number, and it is determined that the power system has reached the static voltage stability limit.

[0080] In an embodiment of the present invention, whether the minimum characteristic root of the improved Jacobian matrix J is zero or the product of the current minimum characteristic root and the minimum characteristic root obtained by the last power flow calculation is negative (i.e., the sign of the minimum characteristic root changes for the first time) is used as a criterion to determine whether the static voltage stability limit is reached. If the current minimum characteristic root is a preset threshold or the product of the current minimum characteristic root and the minimum characteristic root obtained by the last power flow calculation is negative, it is determined that the power system has reached the static voltage stability limit. On the contrary, if the power system has not reached the static voltage stability limit, the power of each node in the power system is adjusted according to the preset strategy, and the calculation is returned to step 101 for recalculation until the current minimum characteristic root is a preset threshold or the product of the current minimum characteristic root and the minimum characteristic root obtained by the last power flow calculation is negative, it is determined that the power system has reached the static voltage stability limit. Among them, the preset adjustment strategy is to continuously increase the output and load according to the given power increase ratio of each load node and generator node, and the adjustment strategy can be set according to demand.

[0081] The method provided by the embodiment of the present invention can take into account the dynamic characteristics of the generator in the continuous power flow calculation, solving the problem that the traditional continuous power flow method cannot be applied to a high-proportion new energy power system because it does not consider the dynamic characteristics of each component in the system. The method of the present invention can obtain a more accurate static voltage stability limit power, thereby improving the accuracy of power grid security and stability analysis and operational safety.

[0082] Figure 2 FIG. 2 is a schematic structural diagram of a continuous power flow calculation system 200 considering generator dynamics according to an embodiment of the present invention. Figure 2 As shown, the continuous power flow calculation system 200 considering the generator dynamics provided by the embodiment of the present invention includes: a power acquisition unit 201, a power flow calculation unit 202, a characteristic root determination unit 203 and a static voltage stability limit determination unit 204.

[0083] Preferably, the power acquisition unit 201 is used to acquire the current power of each node in the power system.

[0084] Preferably, in the power acquisition unit 201, the nodes include: load nodes, synchronous generator nodes and / or new energy generator nodes.

[0085] Preferably, the power flow calculation unit 202 is configured to perform power flow calculation according to current power to determine current operating data of each node.

[0086] Preferably, the power flow calculation unit 202 determines the improved Jacobian matrix according to the current operating data, including:

[0087]

[0088]

[0089]

[0090] Wherein, J is the improved Jacobian matrix; H, N, M, and L are the active-phase angle block matrix, the active-voltage block matrix, the reactive-phase angle block matrix, and the reactive-voltage block matrix, respectively. The block matrices H, N, M, and L are all m×m matrices, where m is the number of nodes; H ij 、N ij 、M ij and L ij are the off-diagonal elements of the block matrices H, N, M, and L, respectively, i≠j, H ii 、N ii 、M ii , L iiare the diagonal elements of the block matrices H, N, M, and L respectively; i = 1, 2, ..., m, j∈i represents all nodes j connected to node i; U i is the voltage at node i; θ i is the phase angle of node i; P Gi and Q Gi are the active power and reactive power injected by the generator of node i, respectively. For non-generator nodes, P Gi and Q Gi The value of G is zero; ij and B ij are the real and imaginary parts of the elements in the i-th row and j-th column of the node admittance matrix respectively; θ ij is the phase angle difference between node i and node j.

[0091] Preferably, in the power flow calculation unit 202, if the node i is a synchronous generator node, the dynamic differential term is calculated in the following manner, including:

[0092]

[0093] If node i is a new energy generator node, the dynamic differential term is calculated using the following method, including:

[0094]

[0095] Among them, X di ' is the transient reactance when node i is a synchronous generator node, E i ' is the internal potential when node i is a synchronous generator node, θ δi is the power angle when node i is a synchronous generator node; k P is the proportional coefficient of the AC voltage control link when node i is a new energy generator node.

[0096] Preferably, the eigenvalue determining unit 203 is configured to determine an improved Jacobian matrix according to current operating data, and calculate a current minimum eigenvalue of the improved Jacobian matrix.

[0097] Preferably, the static voltage stability limit determining unit 204 is configured to determine that the power system has reached the static voltage stability limit when the current minimum characteristic root is a preset threshold or the product of the current minimum characteristic root and the minimum characteristic root obtained from the last power flow calculation is a negative number.

[0098] Preferably, the system further comprises:

[0099] An updating unit is used to adjust the power of each node in the power system according to a preset strategy when the power system has not reached the static voltage stability limit, and enter the power acquisition unit for recalculation until the current minimum characteristic root is a preset threshold or the product of the current minimum characteristic root and the minimum characteristic root obtained by the last power flow calculation is a negative number, thereby determining that the power system has reached the static voltage stability limit.

[0100] The continuous power flow calculation system 200 considering generator dynamics according to the embodiment of the present invention corresponds to the continuous power flow calculation method 100 considering generator dynamics according to another embodiment of the present invention, and will not be described in detail here.

[0101] The invention has been described above with reference to a few embodiments. However, it is readily apparent to a person skilled in the art that other embodiments than the ones disclosed above are equally within the scope of the invention, as defined by the appended patent claims.

[0102] Generally, all terms used in the claims are to be interpreted according to their ordinary meaning in the technical field, unless explicitly defined otherwise herein. All references to "a / the [means, component, etc.]" are to be interpreted openly as referring to at least one instance of the means, component, etc., unless explicitly stated otherwise. The steps of any method disclosed herein do not necessarily need to be performed in the exact order disclosed, unless explicitly stated otherwise.

[0103] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the present application can adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code.

[0104] The present application 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 box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes 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 produce 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.

[0105] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work 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 The function specified in one or more boxes.

[0106] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 The steps for the function specified in one or more boxes.

[0107] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the 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 by the scope of protection of the claims of the present invention.

Claims

1. A continuous power flow calculation method considering generator dynamics, characterized in that: The method comprises: Get the current power of each node in the power system; Perform power flow calculation based on current power to determine the current operating data of each node; Determine an improved Jacobian matrix according to current operating data, and calculate a current minimum eigenvalue of the improved Jacobian matrix; When the current minimum characteristic root is a preset threshold or the product of the current minimum characteristic root and the minimum characteristic root obtained by the last power flow calculation is a negative number, determining that the power system has reached the static voltage stability limit; The method further comprises: When the power system has not reached the static voltage stability limit, the power of each node in the power system is adjusted according to the preset strategy and recalculated until the current minimum characteristic root is a preset threshold or the product of the current minimum characteristic root and the minimum characteristic root obtained by the last flow calculation is a negative number, and it is determined that the power system has reached the static voltage stability limit.

2. The method according to claim 1, characterized in that Determining the improved Jacobian matrix according to the current operating data includes: Wherein, J is the improved Jacobian matrix; H, N, M, and L are the active-phase angle block matrix, the active-voltage block matrix, the reactive-phase angle block matrix, and the reactive-voltage block matrix, respectively. The block matrices H, N, M, and L are all m×m matrices, where m is the number of nodes; H ij 、N ij 、M ij and L ij are the off-diagonal elements of the block matrices H, N, M, and L, respectively, i≠j, H ii 、N ii 、M ii 、L ii are the diagonal elements of the block matrices H, N, M, and L respectively; i = 1, 2, ..., m, j∈i represents all nodes j connected to node i; U i is the voltage at node i; θ i is the phase angle of node i; P Gi and Q Gi are the active power and reactive power injected by the generator of node i, respectively. For non-generator nodes, P Gi and Q Gi The value of G is zero; ij and B ij are the real and imaginary parts of the elements in the i-th row and j-th column of the node admittance matrix respectively; θ ij is the phase angle difference between node i and node j.

3. The method according to claim 2, characterized in that If node i is a synchronous generator node, the dynamic differential term is calculated using the following method, including: If node i is a new energy generator node, the dynamic differential term is calculated using the following method, including: Among them, X di ' is the transient reactance when node i is a synchronous generator node, E i ' is the internal potential when node i is a synchronous generator node, θ δi is the power angle when node i is a synchronous generator node; k P is the proportional coefficient of the AC voltage control link when node i is a new energy generator node.

4. The method according to claim 1, wherein The nodes include: load nodes, synchronous generator nodes and / or new energy generator nodes.

5. A continuous power flow calculation system considering generator dynamics, characterized in that: The system comprises: A power acquisition unit, used to obtain the current power of each node in the power system; The power flow calculation unit is used to perform power flow calculation based on the current power and determine the current operating data of each node; a characteristic root determination unit, configured to determine an improved Jacobian matrix according to current operating data, and calculate a current minimum characteristic root of the improved Jacobian matrix; a static voltage stability limit determining unit, configured to determine that the power system has reached a static voltage stability limit when a current minimum characteristic root is a preset threshold or the product of the current minimum characteristic root and the minimum characteristic root obtained by the last power flow calculation is a negative number; Wherein, the system further includes: An updating unit is used to adjust the power of each node in the power system according to a preset strategy when the power system has not reached the static voltage stability limit, and enter the power acquisition unit for recalculation until the current minimum characteristic root is a preset threshold or the product of the current minimum characteristic root and the minimum characteristic root obtained by the last power flow calculation is a negative number, thereby determining that the power system has reached the static voltage stability limit.

6. The system according to claim 5, characterized in that The power flow calculation unit determines an improved Jacobian matrix according to current operating data, including: Wherein, J is the improved Jacobian matrix; H, N, M, and L are the active-phase angle block matrix, the active-voltage block matrix, the reactive-phase angle block matrix, and the reactive-voltage block matrix, respectively. The block matrices H, N, M, and L are all m×m matrices, where m is the number of nodes; H ij 、N ij 、M ij and L ij are the off-diagonal elements of the block matrices H, N, M, and L, respectively, i≠j, H ii 、N ii 、M ii 、L ii are the diagonal elements of the block matrices H, N, M, and L respectively; i = 1, 2, ..., m, j∈i represents all nodes j connected to node i; U i is the voltage at node i; θ i is the phase angle of node i; P Gi and Q Gi are the active power and reactive power injected by the generator of node i, respectively. For non-generator nodes, P Gi and Q Gi The value of G is zero; ij and B ij are the real and imaginary parts of the elements in the i-th row and j-th column of the node admittance matrix respectively; θ ij is the phase angle difference between node i and node j.

7. The system according to claim 5, characterized in that In the power flow calculation unit, if node i is a synchronous generator node, the dynamic differential term is calculated using the following method, including: If node i is a new energy generator node, the dynamic differential term is calculated using the following method, including: Among them, X di ' is the transient reactance when node i is a synchronous generator node, E i ' is the internal potential when node i is a synchronous generator node, θ δi is the power angle when node i is a synchronous generator node; k P is the proportional coefficient of the AC voltage control link when node i is a new energy generator node.

8. The system according to claim 5, wherein: In the power acquisition unit, the nodes include: load nodes, synchronous generator nodes and / or new energy generator nodes.

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