CN108092249A - Network domain protection method and device - Google Patents

Abstract

The invention provides a network domain protection method and a device, wherein the method comprises the following steps: collecting a detection signal of the power distribution network; wherein the detection signal comprises: current/voltage signals of each node, circuit breaker position signals, isolating switch position signals and element protection action signals; determining the tide data of each node according to the collected current/voltage signals; and executing corresponding actions according to the power flow data, the circuit breaker position signal, the disconnecting switch position signal and the protection action signal of the element. The invention can identify the network structure, judge the fault element, quickly cut off the fault network element, and quickly cut off the adjacent network element after the main protection of the end element refuses, the protection action is quick and accurate, and the range of avoiding accidents is enlarged.

Description

A network domain protection method and device

technical field

The present invention relates to electric power technology, specifically a network domain protection method and device.

Background technique

The power grids (110kV, 220kV) of regional or large and medium-sized enterprises generally set up one or more central substations, and each central substation has 1 to 2 power lines connected to the public power grid. (or enterprise) terminal substation power supply. The self-contained generating sets (or surplus energy generating sets) in the grid are connected to the grid at the central substation. These power distribution networks are relatively independent, and the distribution range is generally small (within 10km).

As shown in Figure 1, it is a typical power distribution network structure diagram. In the power distribution network shown in Figure 1, the components of the system are mainly divided into two categories, namely: network components and terminal components. The network element refers to the distribution element of the central substation or the element that both ends of the ring network may be connected to the power supply (such as: the incoming line of the ring network, the bus tie circuit); the terminal element refers to one end connected to the power supply, the other end to the drop Components connected to voltage transformer equipment.

In the traditional protection configuration, the protection devices of each component are independent of each other, and there is no real-time unified coordination with each other. The protection devices of the network elements and the protection of the terminal elements need to cooperate, the coordination relationship is complicated, and the action time is long; especially when the main protection of the end elements refuses to operate or the circuit breaker fails, because the backup protection takes too long to operate , It is easy to expand the scope of the accident; it directly threatens the stable operation of the network and generating units in this area.

Contents of the invention

In order to quickly and accurately identify faulty network components of the power grid, quickly remove adjacent network components, and quickly and accurately provide protection actions. The embodiment of the present invention provides a network domain protection method, including:

Collect detection signals of the distribution network; wherein, the detection signals include: current/voltage signals of each node, circuit breaker position signals, isolating switch position signals, and component protection action signals;

Determine the power flow data of each node according to the collected current/voltage signal;

The protection action is performed according to the power flow data, the collected position signal of the circuit breaker, the position signal of the isolating switch and the protection action signal of the components.

In the embodiment of the present invention, the execution of the protection action according to the power flow data, the collected circuit breaker position signal, the isolating switch position signal and the protection action signal of the component includes:

Determine the real-time network structure of the distribution network according to the power flow data, the collected circuit breaker position signal, and the disconnector position signal;

According to the determined real-time network structure of the distribution network and the protection action information of the components, the circuit breakers in the power grid are controlled to perform protection actions.

In the embodiment of the present invention, the control of the circuit breaker in the power grid to perform the protection action according to the determined real-time network structure of the distribution network and the protection action information of the components includes:

Determine the neighbors of each element in the grid according to the determined real-time network structure of the distribution network;

According to the protection action information of each element, the circuit breaker that controls the protection action element and its adjacent elements executes the protection action.

In an embodiment of the present invention, the method includes:

The intelligent electronic device IED is used to collect the detection signal of the distribution network and perform protection actions.

At the same time, the present invention also provides a network domain protection device, including: an intelligent electronic device IED and a central main protection device arranged at each node in the power grid; wherein,

The intelligent electronic device IED is used to collect detection signals of the distribution network; wherein, the detection signals include: current/voltage signals of each node, circuit breaker position signals, isolating switch position signals, and component protection action signals;

The central main protection device is used to determine the power flow data of each node according to the collected current/voltage signal, and generate a control instruction according to the power flow data, the collected circuit breaker position signal, the isolating switch position signal and the protection action signal of the component, Control the intelligent electronic device IED to perform protection actions.

In the embodiment of the present invention, the central main protection device includes:

A network structure determining module, configured to determine the real-time network structure of the distribution network according to the power flow data, the collected circuit breaker position signal, and the isolating switch position signal;

The command generation module is used to control the circuit breaker of the protection action element and its adjacent elements to perform protection action according to the protection action information of each element.

In the embodiment of the present invention, the described network structure determination module includes:

an adjacent element determination unit, configured to determine the adjacent elements of each element in the power grid according to the determined real-time network structure of the distribution network;

The instruction generation module generates control instructions according to the determined adjacent elements of each element and the protection action information of the elements.

In the embodiment of the present invention, the intelligent electronic device IED is connected to the central main protection device through an optical fiber.

The present invention sets a set of network domain protection method and device based on the system structure, completes identification of network structure, judgment of faulty components, rapid cutoff of faulty network components, terminal components, and rapid removal of adjacent network components after the main protection refuses to operate, and the protection action is fast , Accurate, and the scope of avoiding accidents is expanded.

In order to make the above and other objects, features and advantages of the present invention more comprehensible, preferred embodiments will be described in detail below together with the accompanying drawings.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments of the present invention. Those skilled in the art can also obtain other drawings based on these drawings without creative work.

Fig. 1 is a typical power distribution network structure diagram in the prior art;

Fig. 2 is a flow chart of a network domain protection method provided by the present invention;

Fig. 3 is a block diagram of a network domain protection device provided by the present invention;

Fig. 4 is a schematic diagram of a network domain protection device provided by an embodiment of the present invention.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

The embodiment of the present invention provides a network domain protection method, as shown in Figure 2, including:

Step S101, collecting detection signals of the distribution network; wherein, the detection signals include: current/voltage signals of each node, circuit breaker position signals, isolating switch position signals, and component protection action signals;

Step S102, determining the power flow data of each node according to the collected current/voltage signal;

In step S103, a protection action is performed according to the power flow data, the collected circuit breaker position signal, the isolating switch position signal and the protection action signal of the component.

In the embodiment of the present invention, performing protection actions in step S103 according to the power flow data, the collected circuit breaker position signals, isolating switch position signals, and component protection action signals includes:

Determine the real-time network structure of the distribution network according to the power flow data, the collected circuit breaker position signal, and the disconnector position signal;

According to the determined real-time network structure of the distribution network and the protection action information of the components, the circuit breakers in the power grid are controlled to perform protection actions.

In the embodiment of the present invention, the control of the circuit breaker in the power grid to perform the protection action according to the determined real-time network structure of the distribution network and the protection action information of the components includes:

According to the determined real-time network structure of the distribution network, determine the adjacent elements of each element in the grid;

According to the protection action information of each element, the circuit breaker that controls the protection action element and its adjacent elements executes the protection action.

The present invention realizes different protection actions for network elements and terminal elements in the power grid. For network elements, faulty elements are quickly removed; for network elements and terminal elements, adjacent element circuit breakers with delay control protection action elements perform failure protection action.

At the same time, the present invention also provides a network domain protection device, as shown in Figure 3, including: an intelligent electronic device IED301 and a central main protection device 302 arranged at each node in the power grid; wherein,

The intelligent electronic device IED301 is used to collect detection signals of the distribution network; wherein, the detection signals include: current/voltage signals of each node, circuit breaker position signals, isolating switch position signals, and component protection action signals;

The central main protection device 302 is used to determine the power flow data of each node according to the collected current/voltage signal, generate control instructions according to the power flow data, the collected circuit breaker position signal, the isolating switch position signal and the protection action signal of the component, and control The intelligent electronic device IED performs protection actions.

In the embodiment of the present invention, the central main protection device includes:

A network structure determining module, configured to determine the real-time network structure of the distribution network according to the power flow data, the collected circuit breaker position signal, and the isolating switch position signal;

The instruction generation module is used to generate control instructions according to the determined real-time network structure of the distribution network and the protection action information of the components.

In the embodiment of the present invention, the described network structure determination module includes:

an adjacent element determination unit, configured to determine the adjacent elements of each element in the power grid according to the determined real-time network structure of the distribution network;

The instruction generation module generates control instructions according to the determined adjacent elements of each element and the protection action information of the elements.

In the embodiment of the present invention, the intelligent electronic device IED301 is connected to the central main protection device 302 through an optical fiber.

Below in conjunction with specific embodiment technical scheme of the present invention is described in further detail as follows:

In the embodiment of the present invention, a set of network domain protection devices based on the system structure is installed in the power distribution network to complete the identification of network structure, judgment of faulty components, rapid cut-off of faulty network components, and rapid removal of adjacent components after the main protection of terminal components refuses to operate. Advanced network components, fast and accurate protection actions, and expanded scope to avoid accidents.

The network domain protection device based on the system structure of the present embodiment is composed of an intelligent measurement/executive element (IED) and a central main protection device (MSP). In this embodiment, the network domain protection device is composed of an optical fiber network based on the IEC61850 protocol by the IED and the MSP , a typical system structure-based network domain protection device system composition, FIG. 4 is a schematic diagram of the protection device disclosed in this embodiment.

In the embodiment of the present invention, the function of each constituent element:

1) Intelligent measurement/executive element IED:

Collect the current/voltage of the circuit, the position signal of the circuit breaker, the position signal of the isolating switch, the action signal of the protection of this circuit and the adjacent terminal components;

Execute the tripping exit command of this loop.

2) Central main protective device MSP:

Receive the collected data of intelligent measurement/executive element (IED);

Determine the network structure of the system operation, and determine the power adjacent components of each component.

Judge the fault state of the system, and determine the fault points and fault types of network elements and terminal elements.

For network components, quickly remove faulty components and make a judgment before backup (failure) protection action.

For terminal components (such as: BT1, BT2, CT1, CT2, DG1, etc.), it is judged that the protection fails according to its protection action signal.

In the case of component protection device and circuit breaker failure, the output command jumps off the adjacent circuit breaker of the faulty component;

3) Fiber optic network:

The intelligent measuring/executing element (IED) in the central substation and the network elements between it and the ring network uses optical fiber to connect with the main processor (MSP) in the central substation to complete the communication between the central master station and the ring network substations , the communication protocol adopts the SV or GOOSE format of IEC 61850. The optical fiber network is distributed within a range of less than 10km, and the existing mature equipment can meet the requirements, with high reliability and low cost.

In the embodiment of the present invention, the central main protection device (MSP) and the optical fiber network adopt a dual redundant configuration.

In this embodiment, the functions performed by the network domain protection device include: judging the network structure of the system operation, determining the fault point and fault type, fast fault removal of network elements, and backup (failure) protection of network elements and terminal elements.

1) Judging the network structure of the system operation:

In this embodiment, according to the position signals of circuit breakers and isolating switches collected by the intelligent measuring/executing element (IED), the central main protection device (MSP) judges Real-time network structure.

According to the real-time network structure, determine the adjacent components on the power supply side of each component (as shown in Figure 4, the adjacent components of component B5 are B2 and B3, and the adjacent components of A7 are A1, A2, A3, A4/A5), in When the backup (failure) protection of this element operates, these circuit breakers are quickly and accurately tripped. Guarantee the rapidity and accuracy of the backup (failure) protection action, and at the same time, the power failure range of the action is the smallest.

2) Determination of fault point and fault type:

Using the current/voltage collected by the intelligent measurement/executive element (IED), the central main protection device (MSP) calculates the direction and size of the power flow at each collection point, and combines the collected terminal data with the difference of the power flow data at the upstream and downstream collection points. The protection action information of the component can be used to judge the location of the fault point and the type of fault.

3) Fault removal of network elements:

The central main protection device (MSP) determines the adjacent network element of the fault point according to the determined fault point location, quickly removes the fault, and starts the backup (failure) protection of this element.

4) Backup (failure) protection of network elements and terminal elements:

According to the judgment result of the fault point and fault type, the action signal of the network element, and the protection action information of the collected end element, judge the protection refusal of the network element and the end element, and delay the action of the fault element according to the real-time system network structure Neighboring elements, faulty elements are excised within the minimum expansion range.

The advantages of the network domain protection device based on the system structure in this embodiment are:

The device adopts dual redundancy mode and integrates mature hardware products to ensure the reliability of the device.

The multi-node information collected by the network domain protection device is integrated, which is easy to judge the fault point and fault type; real-time and accurate prediction of the backup (failure) protection action range, which minimizes the impact of the accident; high sensitivity.

The protection actions of each node of the network element are unified and coordinated, and mutual blocking is realized in the device, which is updated in real time as the operating mode of the system changes, which solves the selectivity of multi-node protection cooperation.

The action time is short, ensuring that the main protection of the entire network operates within 0.1s, and the backup protection (or failure protection) operates within 0.1-0.3s, which saves the coordination time between protections of different components and ensures the quickness of action.

Accurate and fast removal of faults, the loss of faults is controlled to the minimum, which is conducive to the stable operation of the system and generator sets.

Those skilled in the art should understand that the embodiments of the present invention may be provided as methods, systems, or computer program products. Accordingly, the present invention can take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention 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, etc.) having computer-usable program code embodied therein.

The present invention is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It should be understood that each procedure and/or block in the flowchart and/or block diagram, and a combination of procedures and/or blocks in the flowchart and/or block diagram can be realized by computer program instructions. These computer program instructions may be provided to a general purpose computer, special purpose computer, embedded processor, or processor of other programmable data processing equipment to produce a machine such that the instructions executed by the processor of the computer or other programmable data processing equipment produce a An apparatus for realizing the functions specified in one or more procedures of the flowchart and/or one or more blocks of the block diagram.

These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing apparatus to operate in a specific manner, such that the instructions stored in the computer-readable memory produce an article of manufacture comprising instruction means, the instructions The device realizes the function specified in one or more procedures of the flowchart and/or one or more blocks of the block diagram.

These computer program instructions can also be loaded onto a computer or other programmable data processing device, causing a series of operational steps to be performed on the computer or other programmable device to produce a computer-implemented process, thereby The instructions provide steps for implementing the functions specified in the flow chart or blocks of the flowchart and/or the block or blocks of the block diagrams.

In the present invention, specific examples have been applied to explain the principles and implementation methods of the present invention, and the descriptions of the above examples are only used to help understand the method of the present invention and its core idea; meanwhile, for those of ordinary skill in the art, according to this The idea of the invention will have changes in the specific implementation and scope of application. To sum up, the contents of this specification should not be construed as limiting the present invention.

Claims (8)

1. A method for network domain protection, characterized in that said method comprises: Collect detection signals of the distribution network; wherein, the detection signals include: current/voltage signals of each node, circuit breaker position signals, isolating switch position signals, and component protection action signals; Determine the power flow data of each node according to the collected current/voltage signal; The protection action is performed according to the power flow data, the collected position signal of the circuit breaker, the position signal of the isolating switch and the protection action signal of the components. 2. The network domain protection method according to claim 1, wherein said performing protection actions according to power flow data, circuit breaker position signals, isolating switch position signals, and component protection action signals includes: Determine the real-time network structure of the distribution network according to the power flow data, the collected circuit breaker position signal, and the disconnector position signal; According to the determined real-time network structure of the distribution network and the protection action information of the components, the circuit breakers in the power grid are controlled to perform protection actions. 3. The network domain protection method according to claim 2, wherein said controlling the circuit breaker in the power grid to perform the protection action according to the determined real-time network structure of the distribution network and the protection action information of the components includes: Determine the neighbors of each element in the grid according to the determined real-time network structure of the distribution network; According to the protection action information of each element, the circuit breaker that controls the protection action element and its adjacent elements executes the protection action. 4. The network domain protection method according to claim 1 or 3, wherein said method comprises: The intelligent electronic device IED is used to collect the detection signal of the distribution network and perform protection actions. 5. A network domain protection device, characterized in that the device includes: an intelligent electronic device IED and a central main protection device arranged at each node in the power grid; wherein, The intelligent electronic device IED is used to collect detection signals of the distribution network; wherein, the detection signals include: current/voltage signals of each node, circuit breaker position signals, isolating switch position signals, and component protection action signals; The central main protection device is used to determine the power flow data of each node according to the collected current/voltage signal, and generate a control instruction according to the power flow data, the collected circuit breaker position signal, the isolating switch position signal and the protection action signal of the component, Control the intelligent electronic device IED to perform protection actions. 6. The network domain protection device as claimed in claim 5, wherein said central main protection device comprises: A network structure determining module, configured to determine the real-time network structure of the distribution network according to the power flow data, the collected circuit breaker position signal, and the isolating switch position signal; The instruction generation module is used to generate control instructions according to the determined real-time network structure of the distribution network and the protection action information of the components. 7. The network domain protection device according to claim 6, wherein said network structure determining module comprises: an adjacent element determination unit, configured to determine the adjacent elements of each element in the power grid according to the determined real-time network structure of the distribution network; According to the protection action information of each element, the instruction generation module controls the circuit breaker of the protection action element and its adjacent elements to perform protection actions. 8. The network domain protection device according to claim 5, wherein the intelligent electronic device (IED) is connected to the central main protection device through an optical fiber.