KR20130076235A - System and method for tracing reactive power flow, and a medium having computer readable program for excuting the method - Google Patents

Abstract

PURPOSE: An ineffective power flow tracking system, a method thereof, and a medium recording a computer-readable program for the method are provided to efficiently track an end consumer or a production source of ineffective power. CONSTITUTION: An ineffective power flow tracking system (100) includes a power system data extracting unit (110), a line ineffective power generation calculation unit (120), and an ineffective power flow tracking unit (130). The power system data extracting unit extracts data of a power system. The line ineffective power generation calculation unit calculates the generation of ineffective power in each line of the power system by using data. The ineffective power flow tracking unit replaces lines without the generation of the ineffective power which are connected with a virtual bus bar supplying the same ineffective power for each line. The ineffective power flow tracking unit calculates an ineffective power supply bus bar and a load bus bar of the power system by using a proportional sharing rule for the power system. [Reference numerals] (100) Ineffective power flow tracking system; (110) Power system data extracting unit; (120) Line ineffective power generation calculation unit; (130) Ineffective power flow tracking unit

Description

SYSTEM AND METHOD FOR TRACING REACTIVE POWER FLOW, AND A MEDIUM HAVING COMPUTER READABLE PROGRAM FOR EXCUTING THE METHOD}

The present invention relates to a power system, and more particularly to a system, and method for stabilization analysis of the power system.

In general, as a method of tracking power flow in a power system, a method of tracking active power flow using assuming a proportional sharing rule is used. The proportional sharing rule assumes that the currents are more affected by the more flowing lines.

1 is an exemplary diagram for explaining a proportional sharing rule. According to FIG. 1, 30 MW of power flows from bus-i to bus-l, and the proportional sharing rule calculates how much of the 30 MW of power flowing from bus-i to bus-l flows from which bus. have. Of the 30 MW of power, 30 (60/100) = 18 MW came from bus-j and 30 (40/100) = 12 MW came from bus-k.

As such, the proportional sharing rule evaluates its influence according to the ratio of the amount of power supplied. If the above process is continuously performed from the load to the generator, the load can be known from which generator the active power is supplied. do.

However, this method is limited to active power and it is not easy to apply it to reactive power. This is because reactive power is produced from the charging capacity of the line or from the ancestor equipment, unlike the active power produced only by the generator. In addition, unlike active power, where line losses are so small that they can be ignored, reactive power is so large that line losses cannot be ignored.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and a system and method for efficiently tracking the source of production of reactive power consumed by reactive power load and the final consumption of reactive power produced by reactive power generation source. The purpose is to provide.

In order to achieve the above object, the reactive power flow tracking system according to the present invention includes a power system data extracting unit, a line reactive power generation amount calculating unit, and a reactive power flow tracking unit.

The power system data extractor extracts data of the power system, and the line reactive power generation amount calculator calculates the amount of reactive power generated in each line of the power system using the extracted data, and the reactive power flow tracker detects each line and each line. Reactive power in each bus of the power system by using proportional sharing rule for the replaced power system with the line with no reactive power generation connected to the virtual bus supplying reactive power equal to the amount of reactive power generated in Calculate supply bus and load bus.

At this time, the reactive power flow tracking unit with respect to the load busbar of the power system,

의 수학식에 의해 무효 전력 공급 모선을 산출하며, Q_Li는 모선(i)에서 소비되는 무효 전력, α_n는 모선(i)에 대한 모선(n)의 기여도, Q_Gn은 모선(n)에서 발생되는 무효 전력량일 수 있다.

The reactive power supply bus is calculated by the following equation, Q _Li is the reactive power consumed in the bus (i), α _n is the contribution of the bus (n) to the bus (i), and Q _Gn is the bus (n). It may be an amount of reactive power generated.

In addition, the reactive power flow tracking unit for the reactive power supply busbar of the power system,

의 수학식에 의해 부하 모선을 산출하며, Q_Gi는 모선(i)에서 생산되는 무효 전력, β_n는 모선(i)에 대한 모선(n)의 기여도, Q_Ln은 모선(n)에서 소비되는 무효 전력량일 수 있다.

The load bus is calculated by the following equation, where Q _Gi is the reactive power produced at bus (i), β _n is the contribution of bus (n) to bus (i), and Q _Ln is consumed at bus (n). It may be an amount of reactive power.

Also disclosed is an invention in which the system is implemented in the form of a method and a medium on which a computer-readable program for executing the method is recorded.

According to the present invention, it is possible to effectively track the production source of the reactive power consumed by the reactive power load of the power system and the final consumption of the reactive power produced by the reactive power generation source.

1 is a view for explaining an example of tracking the effective power flow using a proportional sharing rule.
2 is a schematic block diagram of one embodiment of a reactive power flow tracking system according to the present invention;
3 is a diagram illustrating an example in which a line of a power system is replaced with an abnormal line in which a virtual bus is connected.
4 is a diagram illustrating a state in which a reactive power supply is installed in the virtual busbar of FIG. 3.
5 is a schematic flowchart for performing a reactive power flow tracking method according to the present invention.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

2 is a schematic block diagram of one embodiment of a reactive power flow tracking system according to the present invention.

In FIG. 2, the reactive power flow tracking system 100 includes a power system data extracting unit 110, a line reactive power generation amount calculating unit 120, and a reactive power flow tracking unit 130. Here, each component of the reactive power flow tracking system 100 may be implemented in hardware, but may be implemented in software and used with a hardware device.

The power system data extractor 110 extracts data of the power system. In this case, the data of the power system may be directly extracted from the measurement device installed in the power system, but the data transmitted and stored from the measurement device may be extracted from the data storage device.

The line reactive power generation amount calculating unit 120 calculates generation amount of reactive power in each line of the power system using the extracted data. At this time, when the generation amount of reactive power is negative, it means that reactive power is consumed in the line.

The reactive power flow tracking unit 130 replaces each line with a line without generating reactive power, and the replaced line is connected to a virtual bus that supplies reactive power equal to the amount of reactive power generated in each line.

Subsequently, a reactive power supply bus and load bus in each bus of the power system are calculated using a proportional sharing rule for the power system in which the line is replaced. At this time, since the power flow tracking method using the proportional sharing rule is already known through effective power flow tracking, a detailed description thereof will be omitted.

의 수학식에 의해 무효 전력 공급 모선을 산출한다. 여기서, Q_Li는 모선(i)에서 소비되는 무효 전력, α_n는 모선(i)에 대한 모선(n)의 기여도, Q_Gn은 모선(n)에서 발생되는 무효 전력량일 수 있다.To this end, the reactive power flow tracking unit 130 with respect to the load busbar of the power system,

The reactive power supply busbar is calculated by the following equation. Here, Q _Li may represent reactive power consumed in bus (i), α _n may represent contribution of bus _n to bus (i), and Q _Gn may represent amount of reactive power generated in bus (n).

의 수학식에 의해 부하 모선을 산출한다. 여기서, Q_Gi는 모선(i)에서 생산되는 무효 전력, β_n는 모선(i)에 대한 모선(n)의 기여도, Q_Ln은 모선(n)에서 소비되는 무효 전력량일 수 있다.In addition, the reactive power flow tracking unit 130 with respect to the reactive power supply busbar of the power system,

The load busbar is calculated by the following equation. Here, Q _Gi may be reactive power produced by bus i, β _n may be the contribution of bus _n to bus i, and Q _Ln may be the amount of reactive power consumed by bus n.

Hereinafter, the embodiment will be described with more specific examples.

In the present invention, in order to reflect the reactive power consumption and the production amount of the line, a virtual bus is made for each line as shown in FIG. 3. 3 is a diagram illustrating an example in which a line of a power system is replaced with an abnormal line in which a virtual bus is connected.

In FIG. 3, a blue arrow indicates a reactive power loss of a line, and a red arrow means supplying reactive power to a grid. If virtual busbars were installed, the lines in the system would all be ideal, with no reactive power or supply.

In addition, ancestors that supply reactive power, such as shunts in the system, are treated on a par with generators, and ancestors that consume reactive power are treated with loads.

To this end, first, the power current calculation is performed to obtain reactive power production / consumption of each line and ancestor equipment. These values are used to determine the amount of reactive power generation and load of virtual buses and buses.

This leaves only the lossless lines, the reactive power generator busbars, and the reactive power load busbars in the system. With this, reactive power flow tracking is performed based on proportional sharing rule, similar to active power flow tracking.

와 같이 나타낼 수 있다. Q_ij는 모선 i-j 사이에 흐르는 무효전력량이고, Q_Gi는 모선 i에서 발전하는 무효 전력량을 나타낸다. 이 식을

으로 변형시키고, i=1, 2 ....n까지 확장시키면, 행렬식

와 같이 나타낼 수 있다. 4 is a diagram illustrating a state in which a reactive power supply source is installed in the virtual busbar of FIG. 3. The sum of the total reactive power flowing into the bus i as shown in FIG.

As shown in Fig. Q _ij represents an amount of reactive power flowing between the bus lines ij, and Q _G i represents an amount of reactive power generated from the bus line i. This expression

And expand to i = 1, 2 .... n, determinant

As shown in Fig.

Based on this, two equations can be obtained as follows.

Here, the equation for Q _Li indicates to which generator the reactive power load bus i is supplied with reactive power. α _n represents the contribution of the generator bus to the load bus and has a value between 0 and 1. The equation for Q _Gi shows which load buses the reactive power produced by the reactive power generator buses is consumed.

5 is a schematic flowchart for performing a reactive power flow tracking method according to the present invention.

 First, ① take real system raw data and perform algae calculation, and output reactive power production of generator and shunt, reactive power flow of line, and reactive power consumption / production of line.

Next, install the virtual bus with the data from the power flow calculation. At this time, the virtual bus is represented by the generator bus or load bus, and the shunt (Shunt) is represented by the generator bus.

Finally, after the virtual bus is installed, the reactive power flow is tracked based on the proportional sharing rule with the flow of reactive power on the track and production / consumption on the bus.

In a power system, voltage is closely correlated with reactive power. Therefore, in order to analyze the voltage stability of the system, analysis of reactive power is essential. The reactive power flow tracking technique according to the present invention can be an important tool in identifying characteristics of reactive power by tracking the reach of reactive power in a real system. This also raises the level of system voltage stability analysis.

In addition, according to the present invention, by tracking the flow of reactive power generated in various types of generators, it is possible to analyze the contribution of the system voltage stability aspect according to the type of generator. In addition, the reactive power flow data in the power system calculated by the present invention may be an essential indicator in the pricing of reactive power, which is a hot topic in recent years.

Although the present invention has been described in terms of some preferred embodiments, the scope of the present invention should not be limited thereby but should be modified and improved in accordance with the above-described embodiments.

100: reactive power flow tracking system
110: power system data extractor
120: line wireless power generation measurement unit
130: reactive power flow tracking unit

Claims (7)

A power system data extracting unit extracting data of the power system;
A line reactive power generation amount calculating unit configured to calculate a generation amount of reactive power in each line of the power system using the data; And
Replace each line with a line without a reactive power generation, connected to a virtual bus that supplies reactive power equal to the amount of reactive power generation at each line,
And a reactive power flow tracking unit configured to calculate a reactive power supply bus and a load bus in each bus of the power system using a proportional sharing rule for the power system in which the line is replaced. The method of claim 1,
The reactive power flow tracking unit with respect to the load busbar of the power system,

The reactive power supply bus is calculated by the following equation, Q _Li is the reactive power consumed in the bus (i), α _n is the contribution of the bus (n) to the bus (i), and Q _Gn is the bus (n). Reactive power flow tracking system, characterized in that the amount of reactive power generated. The method of claim 1,
The reactive power flow tracking unit with respect to the reactive power supply bus of the power system,

The load busbar is calculated by the following equation,
Reactive power flow tracking, characterized in that Q _Gi is the reactive power produced in bus (i), β _n is the contribution of bus (n) to bus (i), and Q _Ln is the amount of reactive power consumed in bus (n) system. A power system data extraction step of extracting data of the power system;
A reactive power generation amount calculating step of calculating generation amount of reactive power in each line of the power system using the data; And
Replace each line with a line without a reactive power generation, connected to a virtual bus that supplies reactive power equal to the amount of reactive power generation at each line,
A reactive power flow tracking method for calculating a reactive power supply bus and a load bus in each bus of the power system using a proportional sharing rule for the power system in which the line is replaced. . 5. The method of claim 4,
The reactive power flow tracking step is performed with respect to the load busbar of the power system,

The reactive power supply bus is calculated by the following equation, Q _Li is the reactive power consumed in the bus (i), α _n is the contribution of the bus (n) to the bus (i), and Q _Gn is the bus (n). Reactive power flow tracking method characterized in that the amount of reactive power generated. 5. The method of claim 4,
The reactive power flow tracking step is for the reactive power supply busbar of the power system,

The load bus is calculated by the following equation, where Q _Gi is the reactive power produced at bus (i), β _n is the contribution of bus (n) to bus (i), and Q _Ln is consumed at bus (n). Reactive power flow tracking method, characterized in that the amount of reactive power. A medium having a computer readable program recorded thereon for executing the method of claim 4.

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