CN113783211B - Power grid three-phase voltage unbalance analysis method based on three-phase tide technology - Google Patents
Power grid three-phase voltage unbalance analysis method based on three-phase tide technology Download PDFInfo
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Classifications
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/26—Arrangements for eliminating or reducing asymmetry in polyphase networks
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/04—Circuit arrangements for ac mains or ac distribution networks for connecting networks of the same frequency but supplied from different sources
- H02J3/06—Controlling transfer of power between connected networks; Controlling sharing of load between connected networks
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J2203/00—Indexing scheme relating to details of circuit arrangements for AC mains or AC distribution networks
- H02J2203/10—Power transmission or distribution systems management focussing at grid-level, e.g. load flow analysis, node profile computation, meshed network optimisation, active network management or spinning reserve management
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E40/00—Technologies for an efficient electrical power generation, transmission or distribution
- Y02E40/50—Arrangements for eliminating or reducing asymmetry in polyphase networks
Abstract
The application relates to a three-phase power flow technology-based power grid three-phase voltage unbalance analysis method, which comprises the following steps: step S1, generating a tide input file according to a network topological graph; s2, acquiring three-phase real-time load power and filling a tide input file; step S3, parameter checking is carried out on the tide input file, and if the parameters are not in a reasonable range, checking parameters are prompted; otherwise, carrying out load flow calculation, outputting three-phase voltage and three-phase current of each node if the load flow is converged, prompting that the load flow is not converged, and rechecking the load flow input file if the load flow is not converged; s4, carrying out power flow calculation according to the checked power flow input file, and analyzing three-phase imbalance causes one by utilizing a power flow result; and S5, outputting a judgment result of the three-phase voltage unbalance according to the analysis result of the step S4. The application can effectively and quickly judge the unbalance cause.
Description
Technical Field
The application relates to the field of power system detection, in particular to a power grid three-phase voltage unbalance analysis method based on a three-phase tide technology.
Background
An ideal power system should operate at a constant frequency (50 Hz in our country) and a standard sinusoidal waveform and supply power to the power consumer according to a specified voltage level. In a three-phase ac power system, the current and voltage magnitudes of the phases should be equal and the phases should differ from each other by 120 °. Since the component parameters in the system are not perfectly linear or symmetrical, the ideal power running state does not exist at any time in the actual power running, thus creating a three-phase imbalance state.
The three-phase unbalance is an important index for measuring the quality of electric energy, and the three-phase unbalance of the electric power system refers to that the amplitude values of three-phase currents (or voltages) are inconsistent, and the amplitude values and the phase differences exceed a specified range, wherein the range can be a standard specified range or a range set by a user. In a power system in a three-phase imbalance condition, there may be a negative sequence component and a zero sequence component in the voltage or current. The negative sequence component and the zero sequence component have a plurality of adverse effects on electrical equipment and interfere with a communication system, so that the treatment of three-phase imbalance becomes a research hot spot. Before the three-phase imbalance is treated, the cause of the three-phase imbalance must be judged to find the key factors affecting the three-phase imbalance.
Disclosure of Invention
In view of the above, the present application aims to provide a three-phase voltage unbalance analysis method for a power grid based on a three-phase tide technology, which can effectively and rapidly determine the cause of unbalance.
In order to achieve the above purpose, the application adopts the following technical scheme:
a power grid three-phase voltage unbalance analysis method based on a three-phase tide technology comprises the following steps:
step S1, generating a tide input file according to a network topological graph;
s2, acquiring three-phase real-time load power and filling a tide input file;
step S3, parameter checking is carried out on the tide input file, and if the parameters are not in a reasonable range, checking parameters are prompted; otherwise, carrying out load flow calculation, outputting three-phase voltage and three-phase current of each node if the load flow is converged, prompting that the load flow is not converged, and rechecking the load flow input file if the load flow is not converged;
s4, carrying out power flow calculation according to the checked power flow input file, and analyzing three-phase imbalance causes one by utilizing a power flow result;
and S5, outputting a judgment result of the three-phase voltage unbalance according to the analysis result of the step S4.
Further, the step S1 specifically includes: according to the network topological graph, the grid structure and grid parameters of the power grid are input, or the three-phase admittance matrix of the transformer and the line and the three-phase voltage unbalance degree threshold C are input, and a tide input file is generated.
Further, the active power and reactive power of the three-phase real-time load are calculated as follows:
wherein: p (P) i Total 、Q i Total The three-phase total active power and the three-phase total reactive power of the node i are; u (U) ik 、I ik The k-th phase voltage amplitude and current amplitude of the node i are represented, and k epsilon (a, b, c); p (P) ik 、Q ik The k-th phase active power and reactive power of the node i are shown.
Further, the three-phase imbalance cause analysis comprises load imbalance, equipment parameter asymmetry and transformer grounding impedance parameter unreasonable analysis.
Further, the step S4 specifically includes:
step S41, calculating the imbalance degree of the three-phase voltages of all the nodes, if the imbalance degree is larger than a threshold C of the imbalance degree of the three-phase voltages, considering that the three-phase voltages of the nodes are not in accordance with the requirement, and if the imbalance degree is smaller than the threshold C, recognizing that the three-phase voltages of the nodes are normal, if all the three-phase voltages of the nodes are normal, considering that the imbalance of the three-phase voltages is not present, outputting a 'normal three-phase voltage', otherwise, continuing step S42.
Step S42, finding out node set { x } of three-phase voltage imbalance from step 41 1 ,x 2 ,…,x n Finding out the nodes directly connected with each node in the node set, and forming a node domain { Θ to be analyzed by the directly connected nodes and the nodes in the node set together 1 ,Θ 2 ,…,Θ n }，Θ n Representing node set { x } 1 ,x 2 ,…,x n Node x in } n The node domain to be analyzed is formed by the node domain and the directly connected nodes;
step S43, taking node set { x } 1 ,x 2 ,…,x n Node x in } 1 Analyzing the node domain theta to be analyzed 1 Load balancing treatment is carried out on all nodes; at this time, if the newly obtained node set { x } 1 ′,x 2 ′,…,x m Node x is absent from' } 1 Then determine node x 1 The three-phase voltage unbalance of (2) is mainly caused by the load unbalance, and the process goes to step S44; if not, the node domain Θ to be analyzed is obtained 1 Turning to step S45;
step S44, traversing the node domain Θ to be analyzed in turn 1 All the nodes of the three-phase load are sequentially provided with the three-phase loadSetting the balance and calculating the power flow to obtain a node domain theta to be analyzed of the balance 1 Node x obtained after loading of ith node in the tree 1 Is of three-phase voltage unbalance epsilon 1i . Epsilon calculation 1min ＝min(ε 1i ) And determining a three-phase load unbalance pair node x of the min node 1 The three-phase voltage imbalance contribution of (2) is greatest;
step S45, taking the node set theta to be analyzed 1 The directly connected equipment is mainly a three-phase transformer and a three-phase circuit, and a to-be-analyzed equipment set ψ is obtained 1 . Collecting psi of the devices to be analyzed 1 Setting the a phase as reference for symmetry, re-executing steps S2, S3 and S41, and if the newly obtained node set { x } 1 ′,x 2 ′,…,x m Node x is absent from' } 1 Then determine node x 1 The three-phase voltage unbalance is mainly caused by the equipment parameter unbalance, and the process goes to step S46; otherwise, the node domain Θ to be analyzed is taken 1 Turning to step S47;
step S46, traversing the device set to be analyzed ψ in sequence 1 Setting the parameters of the devices to be symmetrical one by one, and calculating the power flow to obtain a modified device set ψ to be analyzed 1 Obtaining node x after the ith equipment parameter in the network 1 Is of three-phase voltage unbalance epsilon 1i 'A'; epsilon calculation 1min ′＝min(ε 1i ') and determines the three-phase asymmetric pair node x of the device min 1 The three-phase voltage imbalance contribution of (2) is greatest;
step S47, taking out the device set to be analyzed ψ 1 Middle transformer set T 1 Judging the grounding mode, eliminating the directly grounded transformer to obtain a transformer set T with low current grounding 1 ' assuming that the ground impedance of the transformer conforms to gaussian distribution, the expected original input value is obtained, and the transformer set T is sampled by the monte carlo sampling method 1 Sampling the grounding impedance of all transformers in' and calculating the power flow for multiple times to obtain a node x 1 Is of three-phase voltage unbalance epsilon 1i "calculate ε 1min ″＝min(ε 1i "") to determine ε min "if it is greater than the voltage imbalance threshold C, if not, recording the transformer under the condition of minThe ground impedance configuration is determined as the ground impedance of the transformer to node x 1 The three-phase voltage unbalance of (2) is large, if yes, the result node x is output 1 The cause of the voltage imbalance is not found.
Step S48, continuing the slave node set { x } 1 ,x 2 ,…,x n And (4) taking the next node for analysis, and repeating the steps S41-S47 until all nodes in the node set are traversed.
Further, the load balancing process specifically includes:
further, the three-phase voltage unbalance degree engineering calculation formula is as follows:
wherein: epsilon i Representing the three-phase voltage imbalance of node i.
The utility model provides a three-phase power flow technology-based power grid three-phase voltage unbalance analysis system, includes processor, memory and the computer program that stores on the memory, the step in the power grid three-phase voltage unbalance analysis method is specifically carried out to the processor when executing the computer program.
Compared with the prior art, the application has the following beneficial effects:
the method can quickly and effectively judge the cause of the three-phase voltage unbalance, find out the key factors influencing the three-phase unbalance and provide the three-phase unbalance fault treatment efficiency.
Drawings
FIG. 1 is a flow chart of the method of the present application.
Detailed Description
The application will be further described with reference to the accompanying drawings and examples.
Referring to fig. 1, the application provides a method for analyzing three-phase voltage unbalance of a power grid based on a three-phase tide technology, which comprises the following steps:
step S1, according to a network topological graph, inputting a grid structure of a power grid, inputting grid parameters including positive/zero sequence impedance and transformation ratio of a transformer, positive/zero sequence impedance and positive/zero sequence pair susceptance of a line, or inputting three-phase admittance matrixes of the transformer and the line, and inputting a three-phase voltage unbalance degree threshold C to generate a tide input file;
step S2, filling abc three-phase real-time load power in an input file, obtaining three-phase total active power, three-phase total reactive power, three-phase voltage amplitude and three-phase current amplitude, and generating the active power and reactive power of the abc three-phase real-time load according to the following formula:
wherein: p (P) i Total 、Q i Total The three-phase total active power and the three-phase total reactive power of the node i are; u (U) ik 、I ik Representing the k-th phase voltage amplitude and current amplitude of the node i; p (P) ik 、Q ik The k-th phase active power and reactive power of the node i are represented;
step S3, parameter checking is carried out on the tide input file, and if the parameters are not in a reasonable range, checking parameters are prompted; otherwise, carrying out load flow calculation, outputting three-phase voltage and three-phase current of each node if the load flow is converged, prompting that the load flow is not converged, and rechecking the load flow input file if the load flow is not converged;
s4, carrying out power flow calculation according to the checked power flow input file, and analyzing three-phase imbalance causes one by utilizing a power flow result;
step S41, calculating the imbalance degree of the three-phase voltages of all the nodes, if the imbalance degree is larger than a threshold C of the imbalance degree of the three-phase voltages, considering that the three-phase voltages of the nodes do not meet the requirements, and if the imbalance degree is smaller than the threshold C, recognizing that the three-phase voltages of the nodes are normal, if all the three-phase voltages of the nodes are normal, considering that the imbalance of the three-phase voltages does not exist, outputting a 'normal three-phase voltage', otherwise, continuing step S42;
the three-phase voltage unbalance engineering calculation formula is as follows:
step S42, finding out node set { x } of three-phase voltage imbalance from step 41 1 ,x 2 ,…,x n Finding out the nodes directly connected with each node in the node set, and forming a node domain { Θ to be analyzed by the directly connected nodes and the nodes in the node set together 1 ,Θ 2 ,…,Θ n }，Θ n Representing node set { x } 1 ,x 2 ,…,x n Node x in } n The node domain to be analyzed is formed by the node domain and the directly connected nodes;
step S43, taking node set { x } 1 ,x 2 ,…,x n Node x in } 1 Analyzing the node domain theta to be analyzed 1 The load balancing process of all nodes in the network comprises the following formula:
at this time, if the newly obtained node set { x } 1 ′,x 2 ′,…,x m Node x is absent from' } 1 Then determine node x 1 The three-phase voltage unbalance of (2) is mainly caused by the load unbalance, and the process goes to step S44; if not, the node domain Θ to be analyzed is obtained 1 Turning to step S45;
step S44, traversing the node domain Θ to be analyzed in turn 1 All the nodes of the three-phase network are connected with the three-phase networkThe load is set as balance in turn, and the load flow is calculated to obtain a node domain theta to be analyzed of the balance 1 Node x obtained after loading of ith node in the tree 1 Is of three-phase voltage unbalance epsilon 1i . Epsilon calculation 1min ＝min(ε 1i ) And determining a three-phase load unbalance pair node x of the min node 1 The three-phase voltage imbalance contribution of (2) is greatest;
step S45, taking the node set theta to be analyzed 1 The directly connected equipment is mainly a three-phase transformer and a three-phase circuit, and a to-be-analyzed equipment set ψ is obtained 1 . Collecting psi of the devices to be analyzed 1 Setting the a phase as reference for symmetry, re-executing steps S2, S3 and S41, and if the newly obtained node set { x } 1 ′,x 2 ′,…,x m Node x is absent from' } 1 Then determine node x 1 The three-phase voltage unbalance is mainly caused by the equipment parameter unbalance, and the process goes to step S46; otherwise, the node domain Θ to be analyzed is taken 1 Turning to step S47;
step S46, traversing the device set to be analyzed ψ in sequence 1 Setting the parameters of the devices to be symmetrical one by one, and calculating the power flow to obtain a modified device set ψ to be analyzed 1 Obtaining node x after the ith equipment parameter in the network 1 Is of three-phase voltage unbalance epsilon 1i 'A'; epsilon calculation 1min ′＝min(ε 1i ') and determines the three-phase asymmetric pair node x of the device min 1 The three-phase voltage imbalance contribution of (2) is greatest;
step S47, taking out the device set to be analyzed ψ 1 Middle transformer set T 1 Judging the grounding mode, eliminating the directly grounded transformer to obtain a transformer set T with low current grounding 1 ' assuming that the ground impedance of the transformer conforms to gaussian distribution, the expected original input value is obtained, and the transformer set T is sampled by the monte carlo sampling method 1 Sampling the grounding impedance of all transformers in' and calculating the power flow for multiple times to obtain a node x 1 Is of three-phase voltage unbalance epsilon 1i "calculate ε 1min ″＝min(ε 1i "") to determine ε min If yes, recording the condition of minIn the case of the arrangement of the grounding impedance of the transformer, the grounding impedance of the transformer is determined to be the grounding impedance of the transformer to the node x 1 The three-phase voltage unbalance of (2) is large, if yes, the result node x is output 1 The cause of the voltage imbalance is not found.
Step S48, continuing the slave node set { x } 1 ,x 2 ,…,x n And (4) taking the next node for analysis, and repeating the steps S41-S47 until all nodes in the node set are traversed.
And S5, outputting a judgment result of the three-phase voltage unbalance according to the analysis result of the step S4.
It will be appreciated by those skilled in the art that embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.
The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems) and computer program products according to embodiments of the application. It will be understood that each flow and/or block of the flowchart illustrations and/or block diagrams, and combinations of flows and/or blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
The above description is only a preferred embodiment of the present application, and is not intended to limit the application in any way, and any person skilled in the art may make modifications or alterations to the disclosed technical content to the equivalent embodiments. However, any simple modification, equivalent variation and variation of the above embodiments according to the technical substance of the present application still fall within the protection scope of the technical solution of the present application.
Claims (7)
1. The power grid three-phase voltage unbalance analysis method based on the three-phase tide technology is characterized by comprising the following steps of:
step S1, generating a tide input file according to a network topological graph;
s2, acquiring three-phase real-time load power and filling a tide input file;
step S3, parameter checking is carried out on the tide input file, and if the parameters are not in a reasonable range, checking parameters are prompted; otherwise, carrying out load flow calculation, outputting three-phase voltage and three-phase current of each node if the load flow is converged, prompting that the load flow is not converged, and rechecking the load flow input file if the load flow is not converged;
s4, carrying out power flow calculation according to the checked power flow input file, and analyzing three-phase imbalance causes one by utilizing a power flow result;
step S5, outputting a judgment result of three-phase voltage unbalance according to the analysis result of the step S4;
the step S4 includes:
step S41, calculating the imbalance degree of the three-phase voltages of all the nodes, if the imbalance degree is larger than a threshold C of the imbalance degree of the three-phase voltages, considering that the three-phase voltages of the nodes do not meet the requirements, and if the imbalance degree is smaller than the threshold C, recognizing that the three-phase voltages of the nodes are normal, if all the three-phase voltages of the nodes are normal, considering that the imbalance of the three-phase voltages does not exist, outputting a 'normal three-phase voltage', otherwise, continuing step S42;
step S42, find out the node set { x } of the three-phase voltage imbalance from step S41 1 ,x 2 ,…,x n Finding out the nodes directly connected with each node in the node set, and forming a node domain { Θ to be analyzed by the directly connected nodes and the nodes in the node set together 1 ,Θ 2 ,…,Θ n }，Θ n Representing node set { x } 1 ,x 2 ,…,x n Node x in } n The node domain to be analyzed is formed by the node domain and the directly connected nodes;
step S43, taking node set { x } 1 ,x 2 ,…,x n Node x in } 1 Analyzing the node domain theta to be analyzed 1 Load balancing treatment is carried out on all nodes; at this time, if the newly obtained node set { x } 1 ′,x 2 ′,…,x m Node x is absent from' } 1 Then determine node x 1 The three-phase voltage unbalance of (2) is mainly caused by the load unbalance, and the process goes to step S44; if not, the node domain Θ to be analyzed is obtained 1 Turning to step S45;
step S44, traversing the node domain Θ to be analyzed in turn 1 Setting three-phase loads as balance in sequence, and calculating power flow to obtain a node domain theta to be analyzed of balance 1 Node x obtained after loading of ith node in the tree 1 Is of three-phase voltage unbalance epsilon 1i The method comprises the steps of carrying out a first treatment on the surface of the Epsilon calculation 1min ＝min(ε 1i ) And determining a three-phase load unbalance pair node x of the min node 1 The three-phase voltage imbalance contribution of (2) is greatest;
step S45, taking the node set theta to be analyzed 1 The directly connected equipment comprises a three-phase transformer and a three-phase circuit, and a device set psi to be analyzed is obtained 1 The method comprises the steps of carrying out a first treatment on the surface of the Will beDevice set to be analyzed ψ 1 Setting the a phase as reference for symmetry, re-executing steps S2, S3 and S41, and if the newly obtained node set { x } 1 ′,x 2 ′,…,x m Node x is absent from' } 1 Then determine node x 1 The three-phase voltage unbalance is mainly caused by the equipment parameter unbalance, and the process goes to step S46; otherwise, the node domain Θ to be analyzed is taken 1 Turning to step S47;
step S46, traversing the device set to be analyzed ψ in sequence 1 Setting the parameters of the devices to be symmetrical one by one, and calculating the power flow to obtain a modified device set ψ to be analyzed 1 Obtaining node x after the ith equipment parameter in the network 1 Is of three-phase voltage unbalance epsilon 1i 'A'; epsilon calculation 1min ′＝min(ε 1i ') and determines the three-phase asymmetric pair node x of the device min 1 The three-phase voltage imbalance contribution of (2) is greatest;
step S47, taking out the device set to be analyzed ψ 1 Middle transformer set T 1 Judging the grounding mode, eliminating the directly grounded transformer to obtain a transformer set T with low current grounding 1 ' assuming that the ground impedance of the transformer conforms to gaussian distribution, the expected original input value is obtained, and the transformer set T is sampled by the monte carlo sampling method 1 Sampling the grounding impedance of all transformers in' and calculating the power flow for multiple times to obtain a node x 1 Is of three-phase voltage unbalance epsilon 1i "calculate ε 1min ″＝min(ε 1i "") to determine ε min If the voltage is larger than the voltage unbalance threshold C, if the voltage unbalance threshold C is not larger than the voltage unbalance threshold C, the configuration condition of the grounding impedance of the transformer under the condition of min is recorded, and the grounding impedance of the transformer is judged to be the grounding impedance of the transformer to the node x 1 The influence of the three-phase voltage unbalance of the voltage transformer is large, if yes, the result node x is output 1 The cause of the voltage imbalance is not found;
step S48, continuing the slave node set { x } 1 ,x 2 ,…,x n And (4) taking the next node for analysis, and repeating the steps S41-S47 until all nodes in the node set are traversed.
2. The method for analyzing the three-phase voltage unbalance of the power grid based on the three-phase tide technology according to claim 1, wherein the step S1 is specifically: according to the network topological graph, the grid structure and grid parameters of the power grid are input, or the three-phase admittance matrix of the transformer and the line and the three-phase voltage unbalance degree threshold C are input, and a tide input file is generated.
3. The method for analyzing the three-phase voltage unbalance of the power grid based on the three-phase tide technology according to claim 1, wherein the active power and the reactive power of the three-phase real-time load are calculated as follows:
wherein: p (P) i Total 、Q i Total The three-phase total active power and the three-phase total reactive power of the node i are; u (U) ik 、I ik The k-th phase voltage amplitude and current amplitude of the node i are represented, and k epsilon (a, b, c); p (P) ik 、Q ik The k-th phase active power and reactive power of the node i are shown.
4. The method for analyzing the three-phase voltage unbalance of the power grid based on the three-phase tide technology according to claim 1, wherein the three-phase unbalance cause analysis comprises load unbalance, equipment parameter asymmetry and transformer grounding impedance parameter irrational analysis.
5. The method for analyzing three-phase voltage unbalance of a power grid based on three-phase tide technology according to claim 3, wherein the load balancing process specifically comprises the following steps:
6. a method of analyzing three-phase voltage unbalance of a power grid based on a three-phase power flow technique according to claim 3, wherein the three-phase voltage unbalance engineering calculation formula is as follows:
wherein: epsilon i Representing the three-phase voltage imbalance of node i.
7. A three-phase power flow technology-based power grid three-phase voltage unbalance analysis system, comprising a processor, a memory and a computer program stored on the memory, wherein the processor, when executing the computer program, specifically executes the three-phase power flow technology-based power grid three-phase voltage unbalance analysis method according to any one of claims 1-6.
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| CN108718091A (en) * | 2018-07-09 | 2018-10-30 | 国网福建省电力有限公司 | A kind of linear tidal current computing method of three-phase polar coordinate system applied to active distribution network |
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