KR20230094619A - Flexible power transmission system simulation method and simulator based on grid analysys tool - Google Patents

Abstract

The flexible power transmission system simulation method based on the system analysis tool of the present invention includes modeling the actual system of the field to be applied using the PS-CAD method; Modeling the FACTS equipment applied to the field in a PS-CAD manner; combining the modeling of the system with the modeling of the FACTS facility; reflecting the user's simulated manipulation to the combined modeling; applying a modeling product reflecting the simulation operation to a PS-CAD tool; and receiving the output of the PS-CAD tool and expressing and displaying the output together with the system and the FACTS facility.

Description

Flexible power transmission system simulation method and simulator based on grid analysis tool {FLEXIBLE POWER TRANSMISSION SYSTEM SIMULATION METHOD AND SIMULATOR BASED ON GRID ANALYSYS TOOL}

The present invention relates to a simulator for a Flexible AC Transmission System (FACTS) in which an actual system useful for education and training of operators and new employees is reflected.

Flexible AC Transmission System (FACTS) refers to a new concept power transmission system that can contribute to increase transmission capacity and system stabilization by using high-power semiconductor devices, and is applied for efficient operation of large-capacity long-distance transmission lines. .

However, the operation control of the FACTS facility is made up of manual set-point control based on experience and intuition based on the surrounding system conditions of substation and SCADA substation operators, so there is a limit to optimal operation and various operation controls.

Currently, there is no simulator for education and training for flexible transmission system operators, so existing FACTS (10 locations) operators are educated and trained only with manuals (Text), which reduces field utilization. In addition, with FACTS automatic operation, there is no case where the operator directly controls, and the ability to respond to the field is poor due to lack of experience.

Republic of Korea Registration No. 10-0827571

An object of the present invention is to provide a system analysis tool-based flexible power transmission system (FACTS) simulator and a simulation method using the same, which are inexpensive, easy to implement, and have excellent education and/or training suitability for operation control of FACTS facilities.

A system analysis tool-based flexible transmission system simulation method according to an aspect of the present invention includes modeling an actual system of a field to be applied using a PS-CAD method; Modeling the FACTS equipment applied to the field in a PS-CAD manner; combining the modeling of the system with the modeling of the FACTS facility; reflecting the user's simulated manipulation to the combined modeling; applying a modeling product reflecting the simulation operation to a PS-CAD tool; and receiving the output of the PS-CAD tool and expressing and displaying the output together with the system and the FACTS facility.

Here, in the step of modeling the system using the PS-CAD method, a circuit diagram for display representing the system to be managed as an abbreviated circuit diagram may be created for the convenience of understanding by a manager of the system.

Here, in the step of modeling the FACTS facility using the PS-CAD method, modeling information may be received from the manufacturer of the FACTS facility.

Here, the step of combining the modeling may be performed by connecting the simulated circuit block of the FACTS facility to a node connecting each FACTS facility in the circuit diagram that simulates the system.

Here, the step of reflecting the simulated manipulation to the modeling is, on the combined simulated circuit diagram, the change of the parameter applied by the user to the simulated manipulation of the FACTS facility can be reflected in a manner of changing the corresponding value of the corresponding element of the simulated circuit diagram there is.

Here, in the step of displaying the output of the PS-CAD tool, device response, system P, Q, V, and neighboring system response may be displayed in the form of a graph.

A flexible power transmission system simulator based on a system analysis tool according to another aspect of the present invention includes a field system PS-CAD model in which the actual system of the field to be applied is modeled by the PS-CAD method; FACTS facility PS-CAD model in which the FACTS facility applied to the field is modeled by the PS-CAD method; A model combiner for combining the modeling of the field system PS-CAD model and the modeling of the FACTS facility PS-CAD model; an input interface unit that reflects the user's simulated manipulation to the combined modeling; a PS-CAD tool for performing a simulation through linear equations on a modeling product in which the simulation operation is reflected; and an output interface unit that receives the output of the PS-CAD tool, expresses it together with the system and the FACTS facility, and displays it.

Here, the PS-CAD tool includes a PS-CAD API that performs a command processing interface function for use of PS-CAD; and a PS-CAD system analysis module that performs power system analysis according to a system analysis algorithm of PS-CAD.

Here, the input interface unit transmits an input for simulation manipulation to the PS-CAD API through a TCP/IP communication packet, and the output interface unit transmits a result output by the PS-CAD API through a TCP/IP communication packet. value can be obtained.

Here, the model coupling unit may combine modeling in a manner of connecting the simulated circuit block of the FACTS facility to a node connecting each FACTS facility in the circuit diagram that simulates the system.

If the system analysis tool-based flexible power transmission system (FACTS) simulator and / or simulation method according to the spirit of the present invention is implemented, it is inexpensive, easy to implement, and highly suitable for operation control of FACTS facilities. Education and / or training can be performed There are advantages that can be

The flexible power transmission system simulator and/or simulation method based on the system analysis tool of the present invention has the advantage of improving operational capabilities through effective training for FACTS operators and new/transferred employees. For example, voltage stability can be improved by promptly responding to FACTS failures and nearby grid changes.

The flexible power transmission system simulator and/or simulation method based on the system analysis tool of the present invention has the advantage of being immediately applicable to system change, new facility expansion, etc. with the system analysis tool-based simulator.

1 is a flowchart illustrating a method for simulating a flexible power transmission system based on a system analysis tool according to the spirit of the present invention.
2 is a conceptual diagram of a FACTS simulator proposed by the present invention.
3 is a conceptual diagram showing the input/output form of the PS-CAD tool of the FACTS simulator proposed by the present invention.
4 is a conceptual diagram showing an example of an equivalent circuit and branch current calculation therefor;
5a is an interface screen for inputting a control value of a FACTS facility.
5B is a screen displaying the operation of a power electronic device provided in a FACTS facility or system.
5C is a screen displaying a VI curve at a STATCOM operating point.
5d is an output screen for P, Q, V, and f of the system according to the operation of the FACTS facility.
6A is a screen showing FACTS control and operation point setting input as simulation operation inputs for system analysis tool-based FACTS simulation.
Figure 6b is a screen showing the output and voltage Profile of the system analysis tool-based FACTS simulation.
7 is graphs showing the dynamic response of SVC according to bus failure.
8 is a block diagram showing an embodiment of a flexible power transmission system simulator based on a system analysis tool according to the spirit of the present invention.
9 is a circuit diagram showing an example for explaining the principle of parallel operation.
Fig. 10 is a block diagram showing a configuration example of a user convenience interface (HMI);

In describing the present invention, terms such as first and second may be used to describe various components, but the components may not be limited by the terms. Terms are only for the purpose of distinguishing one element from another. For example, a first element may be termed a second element, and similarly, a second element may be termed a first element, without departing from the scope of the present invention.

When a component is referred to as being connected or connected to another component, it may be directly connected or connected to the other component, but it may be understood that another component may exist in the middle. .

Terms used in this specification are only used to describe specific embodiments, and are not intended to limit the present invention. Singular expressions may include plural expressions unless the context clearly dictates otherwise.

In this specification, the terms include or include are intended to designate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, and one or more other features or numbers, It can be understood that the presence or addition of steps, operations, components, parts, or combinations thereof is not precluded.

In addition, shapes and sizes of elements in the drawings may be exaggerated for clearer description.

In the present invention, a simulator using a commercial PS-CAD tool is presented as a system analysis tool that can be freely controlled by a FACTS operator.

1 is a flowchart illustrating a method for simulating a flexible power transmission system based on a system analysis tool according to the spirit of the present invention.

The illustrated flexible transmission system simulation method includes modeling an actual system of a field to be applied using a PS-CAD method (S110); Modeling the FACTS equipment applied to the field in the PS-CAD method (obtained from the manufacturer) (S120); Combining the modeling of the system and the modeling of the FACTS facility (S130); reflecting the user's simulated manipulation to the combined modeling (S140); Applying a modeling product reflecting the simulation operation to a PS-CAD tool (S160); And receiving the output of the PS-CAD tool, expressing and displaying it together with the system and the FACTS facility (S180).

First, PS-CAD and FACTS as systematic analysis tools will be examined in general.

2 is a conceptual diagram of a FACTS simulator proposed by the present invention.

3 is a conceptual diagram showing the input/output form of the PS-CAD tool of the FACTS simulator proposed by the present invention.

In the present invention, a concept commonly referred to as FACTS is applied to stabilization support devices for systems such as STATCOM, SVC, and TCSC.

PS-CAD, a system analysis tool, is specialized in HVDC and FACTS, enabling step-by-step implementation from control to output of power electronic devices.

Through hybrid simulation, it is possible to link large-scale grids, so it is easy to understand the role of FACTS principles and grids theoretically learned through the same simulation as the actual power system.

EMT-based tools such as PS-CAD obtain new solutions from all operations through linear equations, so detailed simulation is possible, but it takes a long time, but it can be overcome by applying a simulation time minimization technique through parallel high-speed operation do.

Meanwhile, all FACTS facility manufacturers in Korea are required to submit a PS-CAD model (User Defined Model, UDM) to KEPCO, and considering this, the manufacturer's model can be applied to the FACTS simulator, so simulation accuracy can be further increased. .

Next, we look at the basic principles of PS-CAD.

4 is a conceptual diagram illustrating an example of an equivalent circuit and branch current calculation thereof.

PS-CAD is based on Dommel's algorithm, uses integration, and obtains a new solution at each time. At this time, elements (L/C) capable of storing/discharging energy are equalized as shown in Table 1 below. For example, historical current of Δt and equivalent impedance for v(t) can be applied.

As shown in FIG. 4, for example, a G (conductance) matrix can be constructed using a linear network calculation method on an equivalent circuit.

For example, a new current value can be calculated using the result of the previous time period (or initial condition), the voltage of the matrix can be calculated using the current value, and the branch current can be calculated based on the calculated V and I.

It can also be used for surge lightning impulse or transient voltage/current analysis.

In using the PS-CAD tool, HMI provided by each FACTS manufacturer can be implemented. Implement the FACTS and connected system with PS-CAD, a system analysis tool, and utilize the same HMI as the actual one. User Interface), which has an advantage as an education and training system.

5A is an interface screen for inputting control values of FACTS facilities, FIG. 5B is a screen displaying the operation of power electronic devices provided in FACTS facilities or systems, and FIG. 5C is a screen displaying a V-I curve at a STATCOM operating point. 5d is an output screen for P, Q, V, and f of the system according to the operation of the FACTS facility.

FIG. 6A shows FACTS control and operation point setting inputs as simulation inputs for system analysis tool-based FACTS simulation, and FIG. 6B shows output and voltage profiles.

The system analysis tool-based flexible power transmission system (FACTS) simulator according to the spirit of the present invention simulates similarly to the user interface screens of the FACTS facilities shown in FIGS. 5A to 5D, that is, the interface screen for FACTS operation education / training make up them

For example, when the user (trainee) sets the FACTS operating conditions on the input interface screen as shown in FIG. 6A, grid connection simulation is performed, and the output and voltage profile according to the FACTS operating conditions are displayed as output on the output screen as shown in FIG. 6B. , users (trainees) can understand the role of FACTS through this.

7 are graphs showing the dynamic response of the SVC according to bus failure.

The system analysis tool-based flexible power transmission system (FACTS) simulator according to the spirit of the present invention is mounted on a PS-CAD model such as the grads of FIG. 7 to check the dynamic response and protection of FACTS facilities for users (trainees) It is possible to display an interface screen to check the protection operation and the influence of the surrounding system according to the protection operation.

Next, an implementation plan of each detailed step of the method for simulating a flexible power transmission system based on a system analysis tool according to the idea of the present invention according to the flowchart of FIG. 1 will be illustrated.

In the step of modeling the actual system using the PS-CAD method (S110), modeling reflecting the load and distribution connection relationship of the actual system may be performed using the characteristics of the PS-CAD as described above. Additionally, in the step S110, a circuit diagram for display representing the system to be managed as an abbreviated circuit diagram may be created for the convenience of understanding by the manager of the actual system.

Even in the step of modeling the FACTS facility by the PS-CAD method (S120), modeling is performed for each passive / active element constituting each FACTS facility using the characteristics of PS-CAD, and the model is combined in a way However, if the manufacturer of each FACTS facility performs modeling in advance for its own mass-produced product, it may be performed in a manner in which modeling information is received from the manufacturer. In Korea, the latter case is more common.

The step of combining the modeling (S130) may be performed by combining two simulated circuit diagrams reflected as modeling in steps S110 and S120 with each other. For example, it may be performed by connecting the simulated circuit block of each FACTS facility obtained in step S120 to a node connecting each FACTS facility in the circuit diagram that simulates the target actual system obtained in step S110.

For example, in the step of reflecting the simulated manipulation into the modeling (S140), the change in parameters (eg, inductance, impedance, capacitance, etc.) applied by the user to the simulated manipulation of the FACTS facility is reflected on the simulated circuit diagram combined in the step S130. It can be reflected by changing the corresponding value of the corresponding element in the simulated circuit diagram.

The step of applying the modeling product to the PS-CAD tool (S160) may be performed by inputting the input items included in the modeling product according to the manual of the commercial PS-CAD tool, and the commercial PS-CAD tool As it is used, detailed description will be omitted.

In the step S120, when the PS-CAD modeling information for the FACTS facility is received from the manufacturer, additionally, in the step S130, the unit and / or scale of each item included in the PS-CAD modeling information for the FACTS facility is set to the commercial PS -Conversion to units and/or scales suitable for CAD tools can be performed.

In the step of displaying the output of the PS-CAD tool (S180), the result indicated by the output of the PS-CAD tool can be displayed on the display circuit diagram of the target system generated in step S110.

In the displayed circuit diagram, not only the target system but also the FACTS facilities are displayed together. In the case of the FACTS facilities, a simulated circuit for modeling may also be displayed in a simplified form.

In the step S180, device response, system P, Q, V, nearby system response, etc. may be displayed together in the form of a graph. For example, when a user points to a specific device or nearby system, the response of the corresponding device or related system may be displayed as a graph.

Accordingly, the user can check the dynamic response and protection of the FACTS facility, that is, the protection operation loaded in the PS-CAD model and the influence of the surrounding system according to the protection operation, in the graph shown in FIG. 7 .

8 is a block diagram illustrating an embodiment of a flexible power transmission system simulator based on a grid analysis tool according to the spirit of the present invention.

The illustrated flexible power transmission system simulator includes a field system PS-CAD model 110 in which an actual system of a field to be applied is modeled by the PS-CAD method; A FACTS facility PS-CAD model 120 in which the FACTS facility applied to the field is modeled by the PS-CAD method; A model combiner for combining the modeling of the field system PS-CAD model and the modeling of the FACTS facility PS-CAD model; (130); an input interface unit 240 that reflects the user's simulated manipulation to the combined modeling; A PS-CAD tool (600) for performing a simulation through linear equations on a modeling product in which the simulation operation is reflected; and an output interface unit 280 that receives the output of the PS-CAD tool 600, expresses it together with the system and the FACTS facility, and displays the output.

The illustrated PS-CAD tool 600 includes a PS-CAD API 620 that performs a command processing interface function for use of PS-CAD; and a PS-CAD system analysis module (PS-CAD/EMTDC, 640) that performs power system analysis according to the system analysis algorithm of PS-CAD.

The input interface unit 240 and the output interface unit 280 may be implemented as a human machine interface (HMI) 200 for a user (trainee).

To support use by users (trainees) at a remote location, the HMI 200 and the PS-CAD API 620 may communicate with TCP/IP, which is a general communication method. For example, communication may be performed by setting the communication period differently from the operation period or by setting it as a multiple of the operation period. In this case, the input interface unit 240 transmits the input for the simulation operation through a TCP/IP communication packet, and the output interface unit 280 transmits the PS-CAD API 620 through a TCP/IP communication packet. ) can obtain the output value.

The PS-CAD tool 600 uses a commercial tool, but may have a parallel computation structure for increasing the execution speed of a commercial tool installed on a server or the like.

For example, as a parallel operation to improve the PS-CAD processing speed, the Traveling Wave theory can be applied.

9 is a circuit diagram illustrating an example for explaining the principle of parallel operation.

In the structure of FIG. 9 , the overhead line can be modeled with a current source and resistance as shown in the lower right. However, in this current source, the power sending side uses the past current value of the receiving side for calculation, and the receiving side uses the past current value of the sending side for calculation. Therefore, it is possible to determine the boundary between the receiving side and the sending side in the entire power system, and divide subsystems along the boundary. Each subsystem computes on a different computing core, so the power system can improve its processing speed through parallel computing.

10 is a block diagram showing a configuration example of the user convenience interface (HMI).

The illustrated user-friendly interface (HMI) performs various types of data processing, and enables free information exchange and communication with each sub-module.

The above description is merely an example of the technical idea of the present invention, and various modifications and variations can be made to those skilled in the art 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 explain, 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 construed according to the claims below, and all technical ideas within the equivalent range should be construed as being included in the scope of the present invention.

110: Field system PS-CAD model
120: FACTS facility PS-CAD model
130: model coupling part
240: input interface unit
280: output interface unit
600: PS-CAD tool
620 : PS-CAD API
640: PS-CAD/EMTDC

Claims (10)

Modeling the actual system of the field to be applied using the PS-CAD method;
Modeling the FACTS equipment applied to the field in a PS-CAD manner;
combining the modeling of the system with the modeling of the FACTS facility;
reflecting the user's simulated manipulation to the combined modeling;
applying a modeling product reflecting the simulation operation to a PS-CAD tool; and
Receiving the output of the PS-CAD tool and expressing and displaying it together with the system and the FACTS facility
Flexible transmission system simulation method based on system analysis tool including
According to claim 1,
In the step of modeling the system by the PS-CAD method,
A flexible power transmission system simulation method for creating a display circuit diagram expressing a management target system as an abbreviated circuit diagram for the convenience of understanding of the manager of the system.
According to claim 1,
In the step of modeling the FACTS facility by the PS-CAD method,
A flexible transmission system simulation method for receiving modeling information from the manufacturer of the FACTS facility.
According to claim 1,
The step of combining the modeling,
A flexible power transmission system simulation method performed by connecting simulated circuit blocks of FACTS facilities to nodes connecting each FACTS facility in a circuit diagram that simulates a system.
According to claim 4,
In the step of reflecting the simulated manipulation to modeling,
On the combined simulated circuit diagram, a flexible power transmission system simulation method in which a change in a parameter applied by a user by simulated operation of a FACTS facility is reflected in a manner of changing a corresponding value of a corresponding element of the simulated circuit diagram.
According to claim 1,
In the step of displaying the output of the PS-CAD tool,
A flexible transmission system simulation method that displays device response, grid P, Q, V, and neighboring grid response in the form of a graph.
A field system PS-CAD model in which the actual system of the field to be applied is modeled by the PS-CAD method;
FACTS facility PS-CAD model in which the FACTS facility applied to the field is modeled by the PS-CAD method;
A model combiner for combining the modeling of the field system PS-CAD model and the modeling of the FACTS facility PS-CAD model;
an input interface unit that reflects the user's simulated manipulation to the combined modeling;
a PS-CAD tool for performing a simulation through linear equations on a modeling product in which the simulation operation is reflected; and
An output interface unit that receives the output of the PS-CAD tool and expresses and displays it together with the system and the FACTS facility
A flexible power transmission system simulator based on a grid analysis tool that includes
According to claim 7,
The PS-CAD tool,
PS-CAD API that performs a command processing interface function for use of PS-CAD; and
PS-CAD system analysis module that performs power system analysis according to the system analysis algorithm of PS-CAD
A flexible power transmission system simulator including a.
According to claim 8,
The input interface unit,
Transmit input for simulation operation to the PS-CAD API through a TCP/IP communication packet;
The output interface unit,
A flexible power transmission system simulator that acquires the result value output by the PS-CAD API through a TCP/IP communication packet.
According to claim 7,
The model coupling part,
A flexible power transmission system simulator that combines modeling by connecting simulated circuit blocks of the FACTS facility to nodes connecting each FACTS facility in a circuit diagram that simulates the system.

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