WO2012015101A1

WO2012015101A1 - Topology processing method for a power supply system

Info

Publication number: WO2012015101A1
Application number: PCT/KR2010/006568
Authority: WO
Inventors: 윤상윤; 송일근; 권성철; 추철민
Original assignee: 한국전력공사
Priority date: 2010-07-30
Filing date: 2010-09-28
Publication date: 2012-02-02
Also published as: KR101020877B1

Abstract

A topology processing method for a power supply system to which a plurality of transformer substations are linked comprises the steps of: (a) determining the topology processing run mode of the initial drive state and of other run states; (b) running one routine, out of a 1st routine that involves processing a network that is independent with respect to the entire electricity distribution network and a 2nd routine that involves running topology processing with respect to only those transformer substations in which the state of the switchgear has changed and involves partially updating the remaining link structure, after having run topology processing for each transformer substation individually, in accordance with the results of the determination; and (c) generating an independent network by using the connection relationships between electrical busses and branches generated in accordance with the results of the running of step (b), and associated switchgear and the state thereof; and also (d) testing the independent network, the branch and injection validity.

Description

How Topology Is Handled in Feeding Systems

The present invention relates to a method for processing a topology of a power supply system.

Expansion of the monitoring and control range in the distribution line (D / L) unit for smooth operation and control of the smart distribution system in which a large amount of distributed power supply is connected and the continuous operation of the distribution system accommodates the linkage operation of multiple substations. Therefore, topology processing for the distribution system on a branch basis is required.

The topology processing method of the conventional distribution network performs topology processing only on a single trunk line of a radial distribution system, and thus cannot process a system topology in which multiple substations are linked and operated by a constant loop, and through topology analysis of multiple trunks and multiple substations. There is a problem that there is no function of generating an electrical island. In addition, as the introduction of a microgrid type operation due to the inflow of distributed power, etc., a function of determining the validity of each independent system and checking the validity of each facility is required.

3 is a flowchart illustrating a topology processor of the existing power distribution operating system. First of all, the information of the trunk to perform the topology processing designated by the user is input, and the starting equipment information of the trunk is input. Perform a search until all the facilities in the trunk are complete and check the loop status in the middle to generate a loop if the loop is configured. When complete, save the list of discovered facilities and finally display the disconnection diagram and exit.

The topology processor of the existing distribution system operating system only performs topology processing using a physical node for one designated trunk, cannot identify and validate independent systems, and also cannot perform facility validation. In addition, each time the calculation unit and the control unit of the power supply system performs a current calculation, fault calculation, voltage control, etc., the topology processing must be performed.

An object of the present invention is to provide a topology processing method of a power supply system that performs topology processing and independent system processing of a plurality of substations in consideration of a stand-alone operation situation by a constant loop and a distributed power supply of a distribution system.

According to an aspect of the present invention, a method for processing a topology of a power supply system is provided.

The topology processing method of a power supply system in which multiple substations are linked includes (a) determining a mode of performing topology processing in an initial driving state and other performance states, and (b) performing topology processing for each substation according to the determination result. (C) performing one of a first process of processing an independent system for a distribution system and a second process of performing topology processing only on substations whose state of switchgear is changed and partially updating the remaining link structure; and (c) Generating an independent system using the connection relationship between the electric busbar and the branch generated according to the execution of step (b), the link switch, and the state; and (d) checking the validity of the independent system, the branch, and the injection. Steps.

According to an embodiment of the present disclosure, the first process may include receiving a measured value and inspecting an initial topology error, using an electrical bus using a physical bus and switch device connection information and switch state information of a substation in a system. Generating; And creating a link between the generated electrical busbar and the substation, the physical busbar, the branch and the injection.

According to one embodiment of the present invention, the step of generating the electrical bus to generate the electrical bus by using the connection between the physical bus and the switchgear unit and the state of the switchgear in the power distribution system substation unit.

According to an embodiment of the present disclosure, the checking of the initial topology error further includes processing the topology error.

According to an embodiment of the present disclosure, the second process may include checking an error of a state change topology; Generating an electric bus in the substation to which the switchgear with the changed state belongs; Generating a link between the generated electrical busbar and the substation, the physical busbar, the branch and the injection.

According to an embodiment of the present invention, (d) checks the existence of a generator and a load in operation belonging to the independent system to check the validity of the independent system and each facility.

According to an embodiment of the present invention, it has a hierarchical data structure including at least one data table of a branch, a substation, a physical defect, the electrical defect, an associated switch, a switch, a branch, and an injection.

In the topology processing method of a power supply system according to an embodiment of the present invention, the topology processing of all grids in a substation unit may be sequentially processed, thereby enabling topology processing of the entire distribution grid linked by a constant loop.

In addition, the topology processing method of the power supply system can detect the independent system, and can detect the independent operation system by the distributed power source and the micro grid by suggesting a method capable of validating the independent system and the facility. For this purpose, we can suggest a linked switch model.

In addition, the topology processing method of the power supply system can save the computation time by presenting the data structure for the input and output of the topology processor, the subsequent operation and control programs can share the same processing result through the storage of the execution result.

1 is a diagram schematically showing a configuration of a power supply system.

2 is a diagram illustrating a topology processing method of a power supply system according to an exemplary embodiment.

3 is a diagram for explaining topology error checking.

4 shows an example system to which a power supply system is applied.

FIG. 5 is a diagram illustrating a result of topology processing in which all switch devices of FIG. 4 are assumed to be in a closed state.

6 and 7 are diagrams illustrating a topology characteristic matrix when the topology processing is performed with the physical bus bar and the electrical bus with respect to the first substation A of the example system of FIG. 4.

8 is a diagram illustrating storage of the number of bus generations for each substation.

FIG. 9 illustrates a linkage interlock between substations modeled as a zero impedance line with opening and closing information.

10 is a configuration diagram of a database for topology processing according to an embodiment of the present invention.

The present invention may be variously modified and have various embodiments, and specific embodiments will be illustrated in the drawings and described in detail with reference to the accompanying drawings. However, this is not intended to limit the present invention to specific embodiments, it should be understood to include all modifications, equivalents, and substitutes included in the spirit and scope of the present invention.

In describing the present invention, when it is determined that the detailed description of the related known technology may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted. In addition, numerals (eg, first, second, etc.) used in the description process of the present specification are merely identification symbols for distinguishing one component from another component.

In addition, in the present specification, when one component is referred to as "connected" or "connected" with another component, the one component may be directly connected or directly connected to the other component, but in particular It is to be understood that, unless there is an opposite substrate, it may be connected or connected via another component in the middle.

First, the power supply system and the topology processor will be described before describing the topology processing method of the power supply system according to an embodiment of the present invention.

1 is a diagram schematically showing a configuration of a power supply system.

Referring to FIG. 1, an energy management system (EMS) of a power system accurately understands the current state of the system 501 to solve various problems such as voltage and overload occurring in the system 501. It is a system that manages the software and hardware for presenting to the operator.

The power supply system includes a measurement device 503 for measuring data of each part of the system 501, a measurement data server 505 for processing measurement data, a main server 507 for calculating and controlling processed measurement data, topology processing, The topology processor 510 performs periodic and sequential programs such as system state estimation, tidal current calculation, and voltage control, and is calculated in the analysis programs using the topology characteristics of the system 501 generated by the topology processor 510. A client terminal 513 that receives information necessary for system operation and a data management server 515 managing data.

Here, the topology processor 510 is used to search the topology of the system and recognize the path. This checks the electrical connection information and the individual equipment's energized and de-energized operation of the power supply system. For example, the topology processor 510 may identify

buses

1, 2, and 3 that are systems connected through topology search, and may identify that the generator and the load are valid independent systems under pressure.

In addition, the topology processor 510 transmits admittance matrix (Y matrix) information, which is topology characteristic information, to the calculation unit and the control unit of the power supply system. The admittance matrix information consists of each element of the admittance matrix calculated as in Equation (1).

Equation 1

Hereinafter, a topology processing method of a power supply system according to an embodiment of the present invention will be described in detail.

First, referring to FIG. 2, it is first determined whether or not the current performance is the first performance (S10). In this case, it is determined whether the first execution is performed to suit the situation whether the current power supply system has topology information or changes.

As a result of the determination, if the first execution, the initial topology error is checked with the analog measurement value (S20).

Next, an electrical bus is generated using physical buses and switch connection information and switch state information of all substations (S30).

Next, a link between the generated electrical bus and substation, physical bus, branch and injection is generated (S40).

Next, it is determined whether step S40 is completed for all substations (S50).

Next, when the determination progress step S40 is completed, the independent grid which is the scope of analysis is generated by using the connection relationship between the generated electrical buses, the link switch state and the transmission line (S60). Or if step S40 has not been completed, the process returns to step S30.

If the state of the linkage switch is closed, the analytical nodes at both ends of the linkage switch belong to the same independent system. If the linkage switch is open, check whether the linkage is connected to another path. If the search results of all paths do not connect the analytical nodes at both ends, the two nodes are treated as belonging to different independent systems.

Next, the existence of the generator and the load in operation belonging to the independent system is examined to check the validity of the independent system and each facility (S70).

Next, it is determined whether step S70 is performed for all buses (S80). As a result of the determination, when the validation is completed, the topology processing ends. Or, if the validation is not completed, the process returns to step S60.

On the other hand, if it is determined that the current execution state is not the first execution mode, it is determined whether there is a state change of the switch (S90).

If there is a change in the state of the switch, the topology error of the change switch is checked with the surrounding analog measurement value (S100). Or, if there is no state change of the switchgear, it is determined that the validation of all buses is completed and the topology processing is terminated.

Next, update the electrical bus only for the substation to which the changed switch belongs (S110).

Next, the link between the electric bus and the substation, physical bus, transmission line and facilities (injection) generated in the changed substation is updated (S120).

Next, step S60 and step S70 of the first execution mode are performed.

Next, it is determined whether or not step S60 has been performed for all buses (S60). As a result of the determination, when the validation is completed, the topology processing ends. Or, if the validation is not completed, the process returns to step S60.

Hereinafter, the topology processing method illustrated in FIG. 2 will be described in detail with reference to FIGS. 3 to 10.

3 is a diagram for explaining topology error checking.

3 illustrates that the first switch S1 connects the first load LD1 and the second load LD2 to flow tidal currents P / Q due to active power P and reactive power Q. It is shown as an enemy.

In step S20, the first branch (line and transformer) BR1 and the third physical busbar 3 on the side of the physical node and the closest second physical busbar 2 connected to the physical node across all switchgear of the entire substation. Find the second branch BR2 and check whether the algae P / Q flowing above the set value of the branch flows. If the open / close device is searched during the search, the search is stopped.

For example, in the first case, when the measured values of the first branch BR1 and the second branch BR2 both have a value greater than or equal to the set value, the estimated state of the first switchgear S1 is closed. Therefore, when the measured value is open, the measured value is corrected and an alarm is generated. If there is no first branch BR1 and second branch BR2 on the left and right sides, the branch is considered to have a value below the set value.

In the second case, when one of the first branch BR1 and the second branch BR2 is less than or equal to the set value, and when the tidal flow direction is the same as in FIG. 3, the algae measurement value P4 / Q4 of the second load LD2 is greater than or equal to the set value. The estimated state of the first switchgear S1 is closed. Therefore, if the measured value is open, correct the measured value and generate an alarm. If the flow direction is opposite to FIG. 3 and the flow rate measurement value P1 / Q1 of the first load LD1 is greater than or equal to the set value, the estimated state of the first switchgear S1 is closed. Therefore, if the measured value is open, correct the measured value and generate an alarm. If there is no load on the left and right sides, the load is considered to have a value below the set value.

In the third case, except for the first case and the second case, the estimated state of the first switchgear S1 is open. Therefore, if the measured value is closed, correct the measured value and generate an alarm.

In steps S30 and S40, the topology processing of all the grids is sequentially processed in the substation unit, thereby solving the problem that the topology of the entire grid is not processed by performing the topology processing on only one designated trunk line. A case in which the topology is processed based on a physical bus node and a case in which the topology is processed as in the case of the present invention will be described with reference to FIGS. 4 to 7.

4 shows an example system to which a power supply system is applied. Referring to Figure 4, the example system is the first substation (A) and the second substation (B) and the transformer (TR1, TR2) connected to them, the switchgear (S1 ~ S11), load (LD1 ~ LD7), generator ( G1 to G3) and

physical buses

1, 2, ..., 25. In addition, the example system is divided into the main system 40 and the micro grid system 50 when the switch S10 is opened, the micro grid system 50 is capable of independent operation.

6 and 7 are diagrams illustrating a topology characteristic matrix when the main system 40 of FIG. 4 is subjected to a topology processing with a physical busbar and an electrical busbar with respect to the first substation A. Referring to FIG.

Referring to FIGS. 6 and 7, as a result of processing the physical bus shown in FIG. 4 with the electrical bus shown in FIG. 5, the matrix size of 25 × 25 is reduced to 15 × 15, resulting in an admittance matrix size of about 64%. This reduces the amount of calculation of the calculation unit and the control unit.

In step S30, the node processing indicator 1 is allocated to the physical node to which the facility is connected. When grouping physical buses in a substation, their starting point is centered around nodes with node processing indicators of 1, which means that electrical buses must be created in the facility (branch or injection). Node processing indicators include 0, 1, and 2, where 0 is a node that has not been processed and no branch or injection is connected, 1 is a node that has not been processed but a branch or injection is connected, and 2 is a processed node. .

In operation S30, physical buses are grouped to generate a number of electrical buses. This will be described with reference to FIG. 8.

In FIG. 8, each substation is composed of first to Nth substations A, B, C, ..., N. In FIG.

The number of busbars increases from 1 to cumulatively until all substations have been processed. For substation N, add 1 to the number of previously created busbars in the first_bus variable before entering the actual substation process, and store the accumulated busbar counts in the last_bus variable after the substation finishes (after the number of new busbars is created). . Storing first_station_bus (i) = first_bus and storing last_station_bus (i) = last_bus for the substation N is shown in FIG. 8.

The grouping of physical buses inside the individual substations is performed by exploring the connection status of the switchgear centering on the node processing indicator 1, which was processed in step 1 above, and if the contact measurement is closed, group the nodes at both ends and if there is another switchgear. Search. Continue until you find a node that has already been processed or that has a node processing indicator of 1 and assign it to one electrical bus. Repeat until all physical busbars in the substation have been processed.

In step S40, the link between the electrical bus bar and the substation (substation number to which the electric bus belongs, the next bus number belonging to the same substation, the first bus number included in the substation) is stored. The first_station_bus (i) and last_station_bus (i) stored in each substation are extracted, the first_bus and last_bus are extracted, the first bus number for each substation i is assigned, the substation number to which each bus bar belongs, and the next bus bar belonging to the same substation. Assign a number.

In step S40, a free bus is processed. A free bus means an empty bus room and must store the free bus position for the next time the number of buses changes.

Further, in step S40, a link between the electric bus and related facilities is created. Create a link between the electrical busbar and the physical busbar. The link between the physical busbar and each facility (branch / injection, switchgear) is used to create a link between the electrical busbar and each facility.

On the other hand, in step S100, it is checked in which substation a state change has occurred. In step S100, the inspection is performed by comparing the previous measurement state and the current measurement state of all the switchgear with reference to Table 1.

Table 1

Table 1 shows detailed field information and relations for topology processing of the associated switchgear, switchgear, physical bus and substation. In the linked switch and the switch table, there are Old Status and New Status fields to recognize the change of status. Replaced and stored.

In step S100, the error of the topology whose state has changed is checked. As with the initial topology error check (60), all the switchgear belonging to the state-changed substation finds and inspects the physical nodes at both ends and the nearest branches and loads connected to the physical nodes.

In step S110, physical buses for the substations in which the state change has occurred are generated to generate electrical bus numbers. In addition, in step S110, the bus merge is inspected for the substation in which the state change has occurred. Based on the current state, the topology processing finds the equipment connected to all physical buses belonging to the bus based on the generated electric bus. Extract the equipment (branch / injection) number to which the first physical busbar belonging to the electrical busbar is connected, and extract the old topology busbar number (old_bus_number), which is the electrical busbar to which this facility is connected as a result of previous topology processing. For all remaining physical busies belonging to the electric busbar, the connection equipment and the electrical bus (brij_old_bs_num) connected to the equipment as a result of the previous topology processing are extracted.

In operation S110, the number of branches and injection connections for the corresponding bus is counted. Here, if it is found that the previous topology bus number (old_bus_number) and the connected electrical bus (brij_old_bs_num) are different from each other as a result of the previous topology processing, it is determined that coalescing of the electrical busbars has occurred.

In addition, in step S110, the bus split is inspected for the substation where the state change has occurred. Here, the number of branches and injection connections of the corresponding bus bar (state change criterion) obtained in step S110 is compared with the number of connections before the state change, and if the number is different, it is determined that the electrical bus is separated.

In step S110, a free bus is processed. When a bus merge occurs, additional free buses are designated as many as the merged number. To do this, add a free bus immediately after the valid bus and modify the relevant links.

Alternatively, when a bus split occurs, the number of free buses is reduced by the number of the split. To this end, the added valid mothership shall be specified by adding it directly above the maximum parent and modifying the related links.

In step S120, a link is created with facilities related to the electric busbar of the substation in which the state change has occurred. At this time, the link between the electrical busbar and the physical busbar is corrected. In addition, the link between the physical busbar and each facility (branch / injection, switchgear) is used to modify the link between the electrical busbar and each facility.

The topology processing method of the power supply system according to an embodiment of the present invention identifies the independent system 63 and checks the validity of the independent system and equipment.

To do this, the initialization is performed in the first step. The bus type is initialized with the load and the bus state is set to live. Finally, if the independent system to which the mothership belongs is treated as dead, the state changes to dead. It also changes the type of bus by looking at the branch / injection connected to the bus. At this time, the branch state is designated as live. Finally, if the independent system to which the mothership belongs is treated as invalid, the status of the connected branches is also changed to dead. The injection state is set to live. Like branches, they can be changed. Independent systems are designated as invalid. Independent systems can be changed as well as busbars, branches and injections.

In the next step, repeat the entire busbar: Similar to the grouping of physical nodes, the independent system is created by grouping the electrical buses using the connection state of the electric buses and branches (such as lines and transformers) and the open / closed states of the link switches. If the linked switchgear is closed, it is added to the same independent system. If the linked switchgear is open, it is checked whether it belongs to the same independent system through a different path. Repeat this process for all buses.

The following steps are repeated for the entire independent system created in the next step. In the third stage, the first check checks the validity and invalidity by comparing the minimum live parent set point of the independent system with the live parent player of the independent system. Further, in the third step, as a second check, the minimum live generator and load number setting values of the independent system are compared with the live generator and load numbers of the independent system to check the validity / invalidity. If the measured value is less than the designated value, it is treated as invalid. In addition, in the third step, when the absolute amount of the difference between the sum of the measured generation amounts of the independent system and the sum of the load measurement amounts is equal to or greater than the specified value, the third check is invalid.

Here, the determination of validity is designated as a valid independent system only when the first check, the second check and the third check are valid.

The next four steps deal with the invalid independent system. In the case of an independent system checked as invalid, all buses belonging to it and the branches and busts connected to it are treated as dead. This will be described with reference to FIG. 9 further.

In order to process the topology of a plurality of substations, the interlocked switchgear between substations was treated as a model having physical buses 81 at both ends, a line impedance of 0, and opening / closing information 85 as shown in FIG. 9. Using this model, it is possible to process the linkage switchgear between substations in the form of a branch and reflect the state of the opening and closing.

In the topology processing method of the power supply system according to an embodiment of the present invention, the results of the topology processor are stored in the data structure of FIG. 10 by introducing the data structure shown in FIG. Make it available for sharing.

10 is a configuration diagram of a database for topology processing according to an embodiment of the present invention. In FIG. 10, a data table for topology processing is shown, where reference symbol 1 is one receiver and reference symbol N is a plurality of transmitters.

As shown in FIG. 10, the topology processing is performed on a point 91, which is a bundle of substations, and after the transformation of the physical buses 105 into the electric buses 97 in units of the substations 93 belonging to the points. The independent system 95, which is a connection of the electric buses 97, is processed. The substation linkage switch 107 has a link with the physical busbar 105 and belongs to the point 91. The state of the link switch 107 can be recognized because there is measurement information. The physical buses 105 belong to each substation 93, and the physical buses 105 are branches that are general switchgear (breaker, switchgear and other protection devices) 103 and two-node equipment (line, transformer, SVR, etc.) 101) and the link information of the injection 99 which is a one-node facility (load, generator, parallel device (Sh.C, Sh.R, SVC, etc.)). By using this structure, the linkage switch 107 does not belong to the substation 93 so that the topology connection between the substations 93 can be handled, and all system structures have electrical nodes and facilities (switching device, linking switchgear, branch and injection). ), It is possible to process the topology of the entire point 91 including any connection state (radial, loop, etc.) and the substation 93 including any connection state (normally open and always loop) between the trunk lines. .

The above description is merely illustrative of the technical idea of the present invention, and those skilled in the art to which the present invention pertains may make various modifications and changes without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention but to describe the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The protection scope of the present invention should be interpreted by the following claims, and all technical ideas within the equivalent scope should be interpreted as being included in the scope of the present invention.

Claims

In the method of processing the topology of a power supply system linked to multiple substations,

(a) determining a topology processing execution mode of an initial driving state and other execution states;

(b) According to the result of the determination, after performing the topology processing for each substation, the first process of processing the independent system for the entire distribution system and only the substations in which the state of the switchgear is changed, and partially rest the link structure. Performing one of the second processes of updating; And

(c) generating an independent system by using the connection relationship between the electric busbar and the branch, the link switch, and the state generated according to the result of performing the step (b); And

(d) validating said independent system, said branch and injection.
According to claim 1,

The first process,

Receiving a measurement to check for an initial topology error;

Generating an electrical bus using the physical bus and switchgear connection information and the switch state information of the substation in the system; And

And generating a link between the generated electrical busbar and the substation, the physical busbar, the branch, and the injection.
The method of claim 2,

Generating the electrical bus bar

A method for processing a topology of a power supply system, comprising generating an electrical bus by using a connection system between a physical bus and a switchgear and a state of a switchgear in a substation unit.
The method of claim 2,

Examining the initial topology error

Processing the topology error further comprising the step of processing the topology of the power supply system.
According to claim 1,

The second process,

Checking for errors in the state change topology;

Generating an electric bus in the substation to which the switchgear with the changed state belongs;

And generating a link between the generated electrical busbar and the substation, the physical busbar, the branch, and the injection.
According to claim 1,

(D) is

A method for processing a topology of a power supply system, characterized by checking the existence of an operating generator and a load belonging to an independent system to check the validity of the independent system and each facility.
According to claim 1,

And a hierarchical data structure comprising a data table of at least one of a point, a substation, a physical defect, the electrical defect, an associated switchgear, a switchgear, a branch, and an injection.