Research and analysis of dynamic topological coloring of power system based on FO graphics library

1 Overview

Power grid dynamic topology coloring is an advanced application system of power system, topology analysis is an important part of electric power speciality, it is the foundation of power automation analysis, it directly reflects the power equipment modeling of automation system, provides the real-time running network structure of the system, and can be in dynamic coloring mode, Provide an intuitive way for users to understand the operating mode of the system. 2 Data Structure

Topology analysis is essentially the analysis of the connection between devices, on the basis of the formation of electrical connections between the equipment. The state of the equipment (especially the switchgear) in the power system is constantly changing, which causes the electrical connections between the devices to be constantly changing. How to build a data structure that adapts to the characteristics of power system becomes the key.

In theory, the basic data structure (array, queue, stack, etc.) and dynamic Data structures (linked lists, trees, graphs, etc.) can be used to achieve topological analysis, but because of the changing characteristics of the connection, it is obvious that dynamic data structure is more suitable for topological analysis.

The linked list is the most commonly used dynamic data structure, which can express the left and right devices connected to a device in the system according to the left and right chain fields (double linked lists) of the object. 3 noun definition 3.1 definition: Node (connection point, terminal)

The connection point acts as an endpoint of an underlying graphic or a combined graphic, as part of an entity that is set up as a graphic. Connecting lines can be used to correlate the endpoints of different graphics, and when the graphic that places the docking point moves, the connector moves accordingly. 3.2 Definition: Link (connecting line)

A segment that is used to connect endpoints, and cannot be reflexive. The connector has directionality. The port graphics are connected by connecting lines, one port graphic as the starting point of the connector, and the other Port Graphics connector terminal. 3.3 Definition: from,to (Graphics connection direction)

The from direction represents the path that is connected to the neighbor's destination graphic from the graph itself, and the to direction represents the path that is connected from the neighbor shape to its own graphic.

Figure 3.3-1 from direction

Figure 3.3-2 to direction

Table 3.3-3 This article is to standardize the direction of power equipment 3.4 definition: source (sources)

Source is a branch link formed by the combination of power equipment and isolation gate, source is only a virtual branch link, excluding connectors and connection point terminals. The separation of power equipment within it can determine the corresponding power supply state of the other side.

If source is the input stream of the bus power supply, then the source is the from branch of the bus, and if the bus is the input stream of the source power supply, then the source is the to branch of the bus.

Figure 3.4 Various branch layouts in wiring diagrams

Trunk1 bus from direction Source:

L Source1: Circuit breaker, isolation knife gate.

Trunk2 bus from direction Source:

L SOURCE3: Isolation cutter, circuit breaker, Transformer, trolley, circuit breaker.

Trunk1 bus to direction Source:

L SOURCE2: Isolating knife gate. 3.5 Definition: Trunk (BUS)

Trunk a wire that is used to enter lines of each branch and output voltages to other branches. The switch isolation and break breaker switches are connected between trunk and trunk, including 1 circuit breakers, 2 isolation cutters, and 2 grounding cutters.

Figure 3.5-1 Trunk Bus

1) Trunk and branch mapping relationship:

When the topology algorithm is initialized, trunk will form a map mapping relationship with branch.

Figure 3.5-2 Trunk1 (branch1-1,branch1-2), Trunk2 (branch2-1)

3.6 Definition: Bridge (master switch)

Bridge is used to connect two bus lines of power equipment. We stipulate that bridge will eventually converge two trunk busbar, that is, two trunk bus terminals between the end of the connection between the two, not mutually permitted cross boundary.

Figure 3.6 Bridge 3.7 definition: Switch-1 (master-Joint Isolation Knife Gate)

The Switch-1 is used to connect two bus lines of power equipment. The separation of such gates will change the electrification of the circuit upstream or downstream.

Figure 3.7-1 Switch-1

1) Bridge and Switch mapping relationship:

When the topology algorithm is initialized, bridge will form a map mapping relationship with Switch-1.

Figure 3.7-2 Bridge (SWITCH1,SWITCH2)

2) Bridge and Trunk mapping relationship:

When the topology algorithm is initialized, bridge will form a map mapping relationship with trunk.

Figure 3.7-3 Bridge (trunk1,trunk2) 3.8 definition: Switch-2 (grounding knife)

Switch-2 grounding cutters are often used in connection with circuit breaker power equipment. The separation of these gates will not change the electrification status of the upstream and downstream circuits.

Figure 3.8 Switch-2

3.9 Definition: Car (trolley)

The car trolley is used for isolating the electrical equipment of the terminals. The trolley is pushed, connected with the power end, and the trolley is separated from the power source. The separation of such equipment will change the electrical status of the circuit, it is usually associated with the circuit breaker switch use.

Figure 3.9 Car 3.10 definition: Break (breaker switch)

Break breaker switch is used to isolate electrical equipment at both ends of the wiring. The reverse gate is connected with the power supply end; The separation of such equipment will change the circuit charged state, it is usually matched with the use of small cars.

Figure 3.10 Break 4 fo graphics library link function 4.1 getallfromlinks

int getallfromlinks (cfodrawshapelist &listlinks)

Return a list of links so from this shape return the link lines this----;

This function is a public member of Class Cfodrawportsshape, can visit it freely.

This member function is also a virtual function, can Override it if you need,

Defined In:FODrawPortsShape.cpp

return Value

Returns a int type value.

Also

Cfodrawshapelist &listlinks

Specifies A Value.

remarks

Returns the specified value.

Figure 4.1 getallfromlinks Relationship 4.2 getalllinkfromshapes

int getalllinkfromshapes (cfodrawshapelist &listshapes)

Get all shapes, that links, this shape. Return node the shapes this----;

This function is a public member of Class Cfodrawportsshape, can visit it freely.

This member function is also a virtual function, can Override it if you need,

Defined In:FODrawPortsShape.cpp

return Value

Returns a int type value.

Also

Cfodrawshapelist &listshapes

Specifies A Value.

remarks

Returns the specified value.

Figure 4.2 getalllinkfromshapes relationship 4.3 getalllinks

int getalllinks (cfodrawshapelist &listlinks)

Return a list of links so links with this shape return the link lines---->this----;

This function is a public member of Class Cfodrawportsshape, can visit it freely.

This member function is also a virtual function, can Override it if you need,

Defined In:FODrawPortsShape.cpp

return Value

Returns a int type value.

Also

Cfodrawshapelist &listlinks

Specifies A Value.

remarks

Returns the specified value.

Figure 4.3 getalllinks relationship 4.4 getalllinkshapes

int getalllinkshapes (cfodrawshapelist &listshapes)

Get all shapes, links, and this shape. Return the node shapes ' s count. ---->this----,

This function is a public member of Class Cfodrawportsshape, can visit it freely.

This member function is also a virtual function, can Override it if you need,

Defined In:FODrawPortsShape.cpp

return Value

Returns a int type value.

Also

Cfodrawshapelist &listshapes

Specifies A Value.

remarks

Returns the specified value.

Figure 4.4 getalllinkshapes Relationship 4.5 getalllinktoshapes

int getalllinktoshapes (cfodrawshapelist &listshapes)

Get all shapes, that links, to this shape. return node shapes. ---->this,

This function is a public member of Class Cfodrawportsshape, can visit it freely.

This member function is also a virtual function, can Override it if you need,

Defined In:FODrawPortsShape.cpp

return Value

Returns a int type value.

Also

Cfodrawshapelist &listshapes

Specifies A Value.

remarks

Returns the specified value.

Figure 4.5 Getalllinktoshapes Relationship 4.6 getalltolinks

int getalltolinks (cfodrawshapelist &listlinks)

Return a list of links so to this shape return the link lines---->this,

This function is a public member of Class Cfodrawportsshape, can visit it freely.

This member function is also a virtual function, can Override it if you need,

Defined In:FODrawPortsShape.cpp

return Value

Returns a int type value.

Also

Cfodrawshapelist &listlinks

Specifies A Value.

remarks

Returns the specified value.

Figure 4.6 getalltolinks Relationship 4.7 getshapeslinked

int getshapeslinked (cfodrawshapelist &listshapes)

Returns a list of all node shapes this links together 1---->2----->this----->1--->2 Returns all node shapes th at linked. Listshapes--the list of shapes.

This function is a public member of Class Cfodrawportsshape, can visit it freely.

This member function is also a virtual function, can Override it if you need,

Defined In:FODrawPortsShape.cpp

return Value

Returns a int type value.

Also

Cfodrawshapelist &listshapes

Specifies A Value.

remarks

Returns the specified value.

Figure 4.7 getshapeslinked Relationship 4.8 getshapeslinkedfrom

int Getshapeslinkedfrom (cfodrawshapelist &listshapes)

Retrieve node shapes that are linked from this shape. This----->1--->2 return to the nodes that linked from here listshapes--List of shapes.

This function is a public member of Class Cfodrawportsshape, can visit it freely.

This member function is also a virtual function, can Override it if you need,

Defined In:FODrawPortsShape.cpp

return Value

Returns a int type value.

Also

Cfodrawshapelist &listshapes

Specifies A Value.

remarks

Returns the specified value.

Figure 4.8 Getshapeslinkedfrom Relationship 4.9 getshapeslinkedto

int getshapeslinkedto (cfodrawshapelist &listshapes)

Retrieve node shapes that are linked to this shape. 1---->2----->this Return of the nodes that linked. Listshapes--the list of shapes.

This function is a public member of Class Cfodrawportsshape, can visit it freely.

This member function is also a virtual function, can Override it if you need,

Defined In:FODrawPortsShape.cpp

return Value

Returns a int type value.

Also

Cfodrawshapelist &listshapes

Specifies A Value.

remarks

Returns the specified value.

Figure 4.9 Getshapeslinkedto Relationship 5 topological process Analysis

Figure 5 Simplified Model area

As shown in Figure 3.4, there are many devices and conductors in topological relationships, and the relationships are complex, and the following describes the list of internal devices on the left side of the wiring diagram:

1) Source1 internal connection of power equipment:

Break (enter the line switch), Switch-2 (grounding knife), Switch-1 (Isolation knife Gate);

2) Trunk1 internal connection of power equipment:

Source1 (incoming line), SOURCE2 (female Union), Source3 (outlet);

3) Bridge1 internal connection of power equipment:

Switch-1 (left isolating cutter), Switch-2 (left grounding cutter);

Switch-1 (right isolating knife gate), Switch-2 (right grounding cutter).

4) Source2 internal connection of power equipment:

SWITCH-1 (Isolation cutter), Switch-2 (grounding knife), break (switch), car (trolley), break (switch).

The separation of the switches of each of these power devices will have an effect on the separation of the other side or the upstream and downstream circuits. In order to facilitate the simplification of the topological procedure analysis process, we set up three kinds of model regions as shown in Fig. 4: Source region, bus area, and parent-switch region.

The connection between the graph and the graph may appear end-to-end. To avoid the dead loops that occur during the topology process, especially the recursive process, we define a "visit" Boolean flag bit for each entity object. Before traversing, the "visit" Flag of the graph is first emptied "false", and the flag position "true" when traversing to the graphic. The traversal process determines whether the graphic at this time is accessed, the graphics access flag is "false", and the process continues, otherwise the interrupt returns. 5.1 Establishing a topological relationship

We analyze the power system equipment, we can think that each device has one or more terminals, so they are divided into single-ended components, two-sided components and multi-terminal components:

1 single-end component: shunt capacitor, load, generator

2) Both ends of the components: wire, switch, knife Gate

3 Multi-terminal components: Bus, transformer

Connecting two devices means that a pair of terminals between them are connected together. The terminals connected together form a connection point called node. Any device in the system (other than an orphaned device) is connected to one or more nodes. We can get the topology connection of the whole system according to the relationship between the device and the node. Considering the data structure of the graph, the node is represented as the vertex in the graph, and the device attached to the node is represented as the edge connected to the vertex in the graph.

The analysis of the equipment in power system can also get the following characteristics: only the switch (including the Knife Gate) has the characteristics of opening and closing, and the conductor, transformer, bus and so on are only connected characteristics. In fact, it is precisely because of the switch that the electrical connectivity of the power system changes. Therefore, the equipment in the power system is classified into two categories: switching equipment and branch equipment. Two tables are formed in the Program: node switch table and Node slip table. Based on these two tables, you can search for a device connected to any node.

In the topology analysis, according to the real-time state of the equipment, starting from the generator (or Power point bus section) to search, using the node switch table and Node slip table, through the branch connected equipment and closed switch connected equipment induction together to form an electric Island (Island).

When making electric island coloring, according to the division of Electric Island, the electrical status of the equipment in each electric island is the same, whether it is charged or not, the fault, overhaul and so on. The only different in the coloring process is the ring network state, in the coloring of the ring network equipment for special treatment.

1) The electric direction of the ring net and equipment are judged

According to each device connected to the node from the level of power to judge. From the power Point (Level 0) began to search the device downward, each through a device (such as switching equipment, must be the state), the node level plus one, according to the device at both ends of the node level number can be the device's electrical direction and the ring network or not.

2) inspection and fault judgment

According to the equipment on the hanging inspection cards and failure cards to deal with, if there is an electrical island inspection card or failure card, the electrical island of each equipment status is placed for maintenance status.

3) Grounding of the judgment

According to the status of the grounding knife and whether there is a grounding card to judge. If there is a grounding knife in an electric island or a grounding card, the state of the electric island is grounded.

4) switch equipment of five inspection

When the electrical state of Electric Island is analyzed, five inspection of the switch is carried out simultaneously. Inspection method is to assume that the artificial to operate the switch: that is, the original part of the switch is assumed to be closed, the original for the combination of the switch assumed to be disconnected, judge the feasibility of the operation. The main judgment of the following aspects: Live with the knife, switch for the fault, switch for the area, switch ring, closed before the closure of the switch, the knife brake for the fault, the knife gate is suitable for the area, the knife gate ring, with load closing, with load brake. 5.2 Electric Power Equipment Live condition Analysis

Source of the power of the live State provided by the external, its power supply end voltage to the voltage level range. Source inside any power equipment of the partial/close, will cause the whole source of the cent/fit. Link cable itself belongs to the power equipment, it does not participate in the separation, by the other power supply terminals and the state of the power equipment to determine whether they live.

Fig. 5.1 The possible state 5.2.1 Source1 to meet the live conditions before switching on:

1 Source1 area electrification, Bridge1 area power off (the circuit closed will short-circuit);

2 Source1 area power, Bridge1 area charged, Source2 area charged.

3) Source1 area power, Bridge1 area power, Source2 area charged, Source4 area charged, Bridge2 area charged. (The circuit forms a ring net) 5.2.2 Source2 satisfies the charged condition:

1 Source2 area electrification, Bridge1 area power off (the circuit closed will short-circuit);

2 Source2 area power, Bridge1 area charged, Source1 area charged;

3) Source2 area power, Bridge1 area power, Source1 area charged, Source3 area charged, Bridge2 area charged. (The circuit forms a ring net). 5.2.3 Source3 Meet the Live conditions:

1) Source1 area electrification, Bridge1 area power;

2 Source1 area power, Bridge1 area electrification, Source2 area electrification, Bridge2 area power;

3) Source1 area power, Bridge1 area power, Source2 area charged, Source4 area charged, Bridge2 area charged. 5.2.4 Source4 Meet the Live conditions:

1) Source2 area electrification, Bridge1 area power;

2 Source2 area power, Bridge1 area electrification, Source1 area electrification, Bridge2 area power;

3) Source2 area power, Bridge1 area power, Source1 area charged, Source3 area charged, Bridge2 area charged. 5.2.5 Bridge1 Meet the Live conditions:

1 Trunk1 area electrification, Bridge1 on the left side of the isolation knife, Trunk 2 area power;

2 Trunk2 area Electrification, Bridge1 the right side of the isolation knife brake, Trunk 1 area power. 5.2.6 Bridge2 Meet the Live conditions:

1 Trunk3 area electrification, Bridge2 trolley propulsion, Trunk4 area power;

2 Trunk4 area electrification, Bridge2 car propulsion, TRUNK3 area power. 5.3 Power switch turned on from off

When the power switch (or the knife, the following is no longer explained) ready, first to determine whether their state is off, if itself is already in a state, the operation will no longer continue, early end. To determine whether the electrical equipment is charged conditions, to view the status of all its connectors, that is, from and to two direction of the power line.

When the power switch satisfies the closing condition, the power switch, as the source, finds the next power equipment graph (circuit breaker, Knife Gate, connecting line, etc.) through the link list relationship of the connecting line (from), if the next power device is a connecting line, then directly change the topology color of the connection definition. At this point, if the next power equipment state is combined, then repeat the same process directly downstream, whether the device is one-way or two-way, to the other power equipment.

There is a possibility of recursion in the direction of from and to currents, which uses two ideas in the data structure: first "depth First", then "breadth First".

Generally speaking, the "combination" of power switch follows two recursive algorithms, in which the downstream process is invoked.

Figure 5.3 Off->on Conversion Flowchart (omitted) 5.4 power switch from on to turn off

The state of the power switch is composed of a turning point, and the process is much more complex than the 4.3 process.

When the power switch is ready for time-sharing, first determine whether the state is on, if itself is already divided state, the operation will no longer continue, early end. Similarly, to determine whether the electrical equipment is charged conditions, to view the status of all its connectors, that is, from and to two direction of the power line. The connection line is not charged, indicating that either side of the bus loss of electricity, or both sides of the knife gate closed, you can directly divide the gate. The separation of any switch mainly revolves around the connection area and the source area, and the other output switch or grounding cutter will not affect the circuit separation (except illegal operation). 5.4.1 The current switch is the parent switch on the Birdge:

Omitted. 5.4.2 The current switch is the switch of the bus input terminal:

Omitted. 5.4.3 The current switch is the switch of the bus output end:

Omitted. 5.4.4 Current switch is other output switch or grounding cutter:

Omitted.

Figure 5.4 On->off conversion Flowchart (omitted) 5.5 dynamic topology verification

Omitted. 6 Summary

According to the normal topological relationship, the topology layout is completely finished, which is based on the drawing method of Fig. 3.4, simply setting the properties of the power Equipment object on the branch and bus. The whole algorithm is concise, does not depend on the relational database, also does not depend on the topological computation process.