KR20160081067A - Low Voltage DC Distribution System and Distribution Method thereof - Google Patents

Abstract

The present invention relates to a low-voltage direct current distribution system and a low-voltage direct current distribution method wherein a voltage is controlled according to variation of a distributed voltage in multiple distributed power sources installed on a power distribution line for distributing a low-voltage direct current (LVDC). The LVDC distribution method according to the present invention comprises the steps of: allowing multiple intelligent agents, which are installed on a power distribution line, to detect a distributed voltage at a position where each of the intelligent agents is placed and transmit the same to a central controller; allowing the central controller to check whether or not the distributed voltage has varied for each position by using the detected value of the distributed voltage transmitted from each of the intelligent agents; if the variation of the distributed voltage occurs for each position, allowing the central controller to transmit a control command to a corresponding intelligent agent to adjust the magnitude of an output voltage, which is converted by a power conversion device at the position; and allowing each of the intelligent agents that have received the control command to adjust the magnitude of the converted output voltage by controlling the operation of the power conversion device connected to the intelligent agent.

Description

TECHNICAL FIELD [0001] The present invention relates to a low voltage DC distribution system and a distribution method,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a low voltage direct current (LVDC) power distribution system, and more particularly, to a low voltage direct current distribution system and a power distribution system for controlling a voltage in accordance with a variation of a distribution voltage in a plurality of distributed power sources installed on a power distribution line for distributing low- ≪ / RTI >

Currently, DC (DC) distribution is actively studied and applied as a power saving technology. Accordingly, standardization work on reference voltage, distribution voltage, plug, outlet, and the like has been recently carried out.

With the development of digital technology, digitization of existing PCs, TVs, DVDs, cameras, as well as home appliances such as refrigerators and washing machines is accelerating. The power loss in the house due to power conversion (AC-DC) is 20 ~ 30%. DC power distribution reduces the losses due to such power conversion, thereby improving energy efficiency and enabling high-quality power supply.

In addition, the technology fields that have become more and more necessary due to the increase of new and renewable energy are gradually increasing to Internet Data Center (IDC: Internet Data Center), Green PC and Green Building. It is a green growth industry that is expected to lead the related technology and market in the early stage.

This type of DC distribution can be classified into Medium Voltage DC (MVDC) and Low Voltage DC Distribution (LVDC). In case of low voltage DC distribution (LVDC)

Low-voltage direct current distribution (LVDC) has lower power conversion loss than DC power distribution system and less installation and operation cost compared to MVDC, and efficient control of distribution voltage using power converter There is an advantage that it is possible.

In addition, when an accident occurs on the DC distribution line or the load side, it is possible to limit the fault current through the power converter and prevent the accident from spreading to the upper system, thereby improving the reliability of the power supply and replacing the transformer with the power converter. It is possible to build a base for smoother control of the power system.

Despite these advantages, however, there are many problems to be solved in constructing a low voltage DC distribution system. For example, as the distribution voltage (for example, 750 V) is lowered, the magnitude of the line current must be increased in order to supply power to the load of the same size. As a result, the transmission loss in the distribution line is proportional to the square of the line current, which causes a problem that the line loss increases. In addition, since the voltage drop in the line is proportional to the magnitude of the line current, there is a problem that the distribution voltage drops.

Although the study on the low voltage DC distribution has been going on, the technology to solve this problem has not been proposed yet.

Published Patent No. 2014-0081410

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems and technical requirements of the related art, and it is an object of the present invention to provide a low voltage direct current distribution system (hereinafter referred to simply as " low voltage direct current distribution system ") in which a plurality of distributed power sources installed in distribution lines for distributing low voltage direct current And a power distribution method therefor.

Further, the present invention provides a low-voltage DC distribution system and a distribution method thereof that allow rational decision-making in consideration of a variety of distributed power sources installed in a low-voltage direct current (LVDC) distribution line, characteristics of an output margin, There is another purpose.

A low voltage direct current (LVDC) power distribution method according to an embodiment of the present invention includes:

Detecting a distribution voltage at a location where a plurality of intelligent agents installed in a distribution line of a low voltage direct current (LVDC) distribution system is located and transmitting the detected distribution voltage to a central controller; Checking whether the distribution voltage fluctuates at each of the points from the distribution voltage detection values transmitted from the intelligent agents at the central controller; Transmitting a control command to the intelligent agent to adjust the magnitude of the output voltage converted by the power converter at the point in the central controller when a variation in the distribution voltage occurs at each point; And controlling the magnitude of the power-converted output voltage by controlling the operation of the power conversion device connected to the intelligent agent receiving the control command; (LVDC) power distribution system.

In the present invention, the central controller transmits a control command to the intelligent agent when the variation of the detected voltage at each point is out of the predetermined reference voltage range.

In the present invention, the conversion width of the power conversion apparatus is determined according to the variation range of the distribution voltage.

In the present invention, it is preferable that, after the step of adjusting the magnitude of the power-converted output voltage, at the central controller, based on the detection value of the distribution voltage of each point to the distribution line transmitted from each intelligent agent, Determining whether the distribution voltage has returned to a predetermined normal range; Transmitting a control command for controlling the amount of power generated by the distributed power source to the intelligent agent when the determination result does not return to the normal range; Adjusting an amount of power generation of the distributed power supply in each intelligent agent that receives the control command; .

In the present invention, the power generation amount of the distributed power source is determined according to the difference between the detection value of the distribution voltage at each point and the normal range.

In the present invention, the step of regulating the amount of power generation of the distributed power source adjusts the amount of power generation in the order of the distributed power sources having a higher voltage sensitivity index (VSF) when it is determined that the distribution voltage does not return to the normal range at the plurality of points.

In the present invention, when the low-voltage direct current (LVDC) power distribution system has a total of N lines, the voltage sensitivity index (VSF) according to the voltage variation of the j-th line when the power generation amount of the distributed power source of the i- ,

와 같이 계산되고,

Lt; / RTI >

The voltage sensitivity index (VSF) according to the voltage variation of the i-th line is given by the following equation,

와 같이 계산된다.

.

(Vi: voltage of i-th line, Gij: inductance between i-th line and j-th line, and Vj: voltage of j-

A low voltage direct current distribution system according to an embodiment of the present invention includes:

In a low voltage direct current (LVDC) power distribution system including multiple distributed power sources and loads,

A plurality of power converters respectively installed on the power distribution lines of the low voltage direct current (LVDC) power distribution system to perform power conversion in front of the distributed power sources; A plurality of intelligent agents connected to the respective power conversion devices on the power distribution lines for detecting power distribution voltages at their own points and controlling operations of the power conversion devices connected to the power conversion devices according to control commands received from a higher level; And determining whether the distribution voltage fluctuates for each of the points from the distribution voltage detection values received from the intelligent agents, and when a variation of the distribution voltage occurs at each of the points, a magnitude of the output voltage converted by the point- A central controller for sending a control command to the intelligent agent to adjust; .

In the present invention, the intelligent agent may control the operation of the power conversion device connected to the intelligent agent to adjust the magnitude of the power-converted output voltage in accordance with the variation of the distribution voltage for each point according to the control command received from the central controller .

In the present invention, the central controller transmits a control command to the intelligent agent when the variation of the voltage detected at each of the points is out of the predetermined reference voltage range.

In the present invention, the central controller, after transmitting the control command to the intelligent agent, determines a distribution voltage at each of the points based on the detection value of the distribution voltage of each point to the distribution line transmitted from each intelligent agent And if it does not return to the normal range, transmits a control command to the intelligent agent to adjust the power generation amount of the distributed power.

In the present invention, the intelligent agent adjusts the power generation amount of the distributed power source according to the control command received from the central controller.

In the present invention, the central controller transmits a control command to the intelligent agent to regulate the power generation amount in the order of the distributed power source having a high voltage sensitivity index (VSF).

According to the present invention, even when the distribution voltage is lowered in constructing the low voltage direct current (LVDC) distribution system, since the voltage of each distributed power source is efficiently compensated or controlled by a plurality of agents installed on the distribution line, .

In addition, according to the present invention, even if a voltage drop occurs in a low-voltage DC wiring line, a desired DC voltage can be efficiently supplied to a customer.

1 is a block diagram of a low voltage direct current (LVDC) power distribution system in accordance with the present invention;
Figure 2 is a schematic diagram illustrating each intelligent agent and central controller in a low voltage direct current (LVDC) distribution system according to an embodiment of the present invention;
3 is a flow diagram illustrating a power distribution method in a low voltage direct current (LVDC) power distribution system according to an embodiment of the present invention,
FIG. 4 is a diagram illustrating a process of controlling a power generation amount of a distributed power source in a low voltage direct current (LVDC) power distribution system according to an embodiment of the present invention;
5 is a diagram illustrating an example of a distribution system for explaining a process of obtaining a voltage sensitivity index (VSF) according to an embodiment of the present invention.
Figure 6 is an equivalent diagram of Figure 5;

Hereinafter, some embodiments of the present invention will be described in detail with reference to exemplary drawings. It should be noted that, in adding reference numerals to the constituent elements of the drawings, the same constituent elements are denoted by the same reference numerals whenever possible, even if they are shown in different drawings. In the following description of the embodiments of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the difference that the embodiments of the present invention are not conclusive.

In describing the components of the embodiment of the present invention, terms such as first, second, A, B, (a), and (b) may be used. These terms are intended to distinguish the constituent elements from other constituent elements, and the terms do not limit the nature, order or order of the constituent elements. When a component is described as being "connected", "coupled", or "connected" to another component, the component may be directly connected or connected to the other component, May be "connected," "coupled, " or" connected. &Quot;

1 is a block diagram of a low voltage direct current (LVDC) distribution system according to the present invention.

Referring to Figure 1, a low voltage direct current (LVDC) power distribution system 100 in accordance with the present invention includes a plurality of power sources 110 connected to a low voltage direct current (LVDC) distribution line 10, a plurality of loads 120, And an apparatus 130. The power generator 110 means a power generator that generates electric power such as a cogeneration power plant, a micro turbine, a solar power generator, a wind power generator, a fuel cell, a diesel generator, and the like. Also, the load 120 is a device that consumes power, and an energy storage system (ESS) 130 is a device that stores energy and supplies energy stored when necessary. In the present embodiment, the energy storage device 130 may be included in the power generator 110 in a broad sense in terms of supplying stored energy.

This low voltage direct current (LVDC) power distribution system 100 is a small scale power supply system composed of a plurality of distributed power sources such as a power source 110 and an energy storage device 130 and a load 120, It is an active distribution system that can be determined. Here, the distributed power source includes a power-consuming power generating unit as well as a power-consuming load. This is because it seems to produce electricity from the notion that by reducing the power consumption in the load, it can supply that amount of power to the other side with the opposite benefit.

As shown in the figure, a low voltage direct current (LVDC) power distribution system 100 is connected to an AC power source side 30 such as a power plant and the AC high voltage is converted into a low voltage direct current (LVDC) (10). Although the power source 110, the load 120, and the energy storage device 130 are shown separately for convenience of explanation of the present invention, it is to be understood that each of the numbers may be changed.

In this embodiment, the power conversion device 140 and the intelligent agent 150 are connected to the front ends of the power generation sources 110 and the energy storage devices 130, respectively. The power conversion device 140 converts the voltage supplied through the distribution line 10 and supplies the voltage generated from each power generation source 110 and the energy storage device 130 to the distribution line 10. The power conversion device 140 may include, for example, a DC / DC converter or an AC / DC converter. In addition, each intelligent agent 150 controls the operation of the power conversion device 140 connected thereto. This controls how much voltage the power conversion device 140 converts to the voltage supplied from each power generation source 110 and the energy storage device 130. That is, the intelligent agent 150 detects the voltage supplied through the distribution line 10 of the low voltage direct current (LVDC) power distribution system 100, and when the detected voltage is within the range of a predetermined reference voltage And controls the converted voltage in the power conversion apparatus 140 when the voltage is off. This is because when the distribution voltage of the low voltage direct current (LVDC) distribution system 100 according to the present invention varies due to a predetermined cause, for example, when the distribution voltage supplied through the distribution line 10 rises or falls, A voltage is supplied from each power generating source 110 and the energy storage device 130 to the power distribution line 10 through the power conversion device 140 to control the power conversion device 140 so as to supply a desired voltage, To be higher or lower than the rated voltage of the power source 110 and the energy storage device 130. [ For example, when the distribution voltage falls, the power conversion apparatus 140 converts the output voltage to a voltage higher than the rated voltage and outputs the converted voltage. In contrast, when the distribution voltage rises, So that the increased distribution voltage can be compensated for. Each load 120 may be connected to a load controller 40 for controlling the load. Each of these intelligent agents 150 is controlled and managed by the central controller 210 as shown in FIG.

2 is a schematic diagram illustrating each intelligent agent and a central controller in a low voltage direct current (LVDC) distribution system according to an embodiment of the present invention.

Referring to FIG. 2, in the low voltage direct current (LVDC) distribution system 100 according to the present invention, a plurality of intelligent agents 150 are controlled by the central controller 210.

As described above, the plurality of intelligent agents 150 are connected to each of the plurality of power generation sources 110 constituting the low voltage direct current (LVDC) power distribution system 100 and each power conversion device 140 connected to the energy storage device 130 It is linked to one-on-one. The intelligent agent 150 stores the state information of the power generation source 110, the energy storage device 130 and the power conversion device 140 connected to the intelligent agent 150. The intelligent agent 150 detects the power distribution voltage at the power distribution line 10, The power conversion apparatus 140 is controlled to adjust the magnitude of the voltage to be converted by the power conversion apparatus 140 when the supplied power distribution voltage is out of the predetermined reference voltage range.

The central controller 210 allows for the management and control thereof through communication with a plurality of intelligent agents 150. Particularly, in this embodiment, the central controller 210 controls the power generation unit 110 and the energy storage unit 130 in the power conversion unit 140 according to the change of the distribution voltage provided from each intelligent agent 150 And controls the operation of each power converter 140 to adjust the converted voltage. At this time, in order to determine which position of the distribution line 10 the distribution voltage fluctuates, when each intelligent agent 150 transmits the voltage detected by the intelligent agent 150 to the central controller 210, It is preferable to transmit the information (ID) together. Thus, when a change in the distribution voltage is detected from the plurality of intelligent agents 150, it is determined which position the voltage change has occurred, how much voltage change has occurred, and the like, and the intelligent agent 150 at that position The control command is transmitted to adjust the power generation amount.

3 is a flow diagram illustrating a power distribution method in a low voltage direct current (LVDC) power distribution system in accordance with an embodiment of the present invention.

3, in the distribution method in the low voltage direct current (LVDC) distribution system 100 according to the present invention, the distribution voltage at the point where the intelligent agent 150 installed in the distribution line 10 is located (S101), and preferably transmits its detection result to the central controller 210 together with its own positional information and unique identification information (S103).

The central controller 210 confirms the distribution voltage at each point from the detection result transmitted from each intelligent agent 150 (S105) and, at a point where the distribution voltage fluctuates, the central controller 210 performs power conversion The conversion width of the voltage converted in the device 140 is determined and a control command is transmitted to the intelligent agent 150 to adjust the conversion width of the conversion voltage (S107).

Then, each intelligent agent 150 receiving the control command controls the operation of the power conversion apparatus 140 connected thereto to perform power conversion for compensating for the voltage variation (S109). At this time, in the present embodiment, when the variation of the voltage detected at each point of the central controller 210 is out of the predetermined reference voltage range, the central controller 210 transmits a control command to the intelligent agent 150.

For example, when the magnitude of the distribution voltage deviates from a predetermined reference voltage, the power conversion apparatus 140 performs power conversion within a range of ± 5%. That is, each of the intelligent agents 150 controls the output voltage of the power conversion apparatus 140 connected thereto, for example, from 95% to 105%, thereby compensating for the distributed power distribution voltage in the power distribution system. Of course, these numerical values are provided for convenience of description of the present invention, and the present invention is not limited thereto. Thereby, the supply voltage of the distribution line 10 changes globally, and the voltage of the bus with the maximum voltage fluctuation also increases / decreases together so that it can be adjusted to the normal range.

If the output terminal voltage of the power inverter 140 is increased by x% for example, the voltage at the maximum fluctuation point may be higher or lower than x% depending on the distribution distance and characteristics of the power line. As a general rule of thumb, the radial distribution system has a slightly higher end voltage than x%. These fluctuations can be accurately obtained through algae calculations.

However, even when the magnitude of the voltage output from the power conversion apparatus 140 varies due to characteristics of the power distribution line or a predetermined cause, the power distribution voltage of the power distribution system may not be compensated. In this case, the distributed power source connected to a specific line can vary the active power output to the power distribution system to control the voltage of the entire power distribution system. This is because when voltage variation occurs at a specific point and the power conversion apparatus 140 at the corresponding point is controlled to change the output voltage to be converted at the output stage and the entire power distribution voltage is not compensated for, The central controller 210 controls the power generation amount of the plurality of power generation sources 110 and the energy storage device 130 arbitrarily determined.

After this, in step S109, the central controller 210 continuously receives the measured voltage at each point of the distribution line 10 transmitted from the intelligent agent 150 and determines whether the distribution voltage at the corresponding point returns to the normal range (S111). If it is not returned to the normal range, control is performed to adjust the power generation amount of the distributed power source, that is, the power source 110 or the energy storage device 130, through each intelligent agent 150 (S113). That is, when the output voltage of the power conversion apparatus 140 at a specific point is varied within a predetermined range and the voltage variation of the power distribution voltage can not be compensated, the power generation amount of the power generation source 110 and the energy storage device 130 Thereby compensating for the voltage fluctuation of the distribution voltage.

At this time, the power generation amount of the distributed power source is determined according to the value corresponding to the difference between the detection value of the distribution voltage at each point and the normal range at the present point in time. This is to determine how much power must be generated to determine if the distribution voltage returns to the normal range. Particularly, in the present invention, when it is determined that the distribution voltage does not return to the normal range at a plurality of points, the power generation amount of the distributed power source is adjusted in order of the position where the VSF is high. The higher the VSF, the greater the magnitude of the voltage that is compensated for even a small amount of power generation in the distributed power supply, so it is desirable to control the power generation amount in order of the distributed power supply with a high VSF.

4 is a diagram illustrating a process of controlling the amount of power generation of a distributed power source in a low voltage direct current (LVDC) power distribution system according to an embodiment of the present invention.

Referring to FIG. 4, in the present invention, if the output varies by ΔPj of the distributed power source connected to the jth line, the influence of ΔVj / ΔPj on the jth line and the influence of ΔVq / ΔPj on the qth line . Therefore, when the values of DELTA Vj / DELTA Pj and DELTA Vq / DELTA Pj are known, it is possible to calculate how much output fluctuation is to be commanded from the distributed power source when voltage control of the j-th line and the q-th line is required. In the present invention, the values of DELTA Vj / DELTA Pj and DELTA Vq / DELTA Pj are defined as Voltage Sensitivity Factor (VSF). VSF can be obtained through algae calculation. In particular, the process of obtaining VSF regardless of the type of distribution system is as follows.

5 is an exemplary diagram of a power distribution system for explaining a process of obtaining a voltage sensitivity index (VSF) according to an embodiment of the present invention, and FIG. 6 is an equivalent diagram of FIG.

Referring to FIG. 5, the present invention employs a method capable of calculating VSF even in a distribution system implemented as a loop even if it is not radial, as shown in the figure. This is a universal method that can be applied consistently and uniformly to any type of distribution system. Assuming the generalized i-th line (or node) in the power distribution system of Fig. 5, it can be expressed by a circuit diagram as shown in Fig.

In the example of FIG. 6, Vi is the voltage of the i-th bus, Ii is the current flowing into the i-th bus, Iij is the current flowing from the i-th bus to the j-th bus, g _i1 is the conductance : Inverse of the resistance), and g _in is the conductance between the ith bus and nth bus.

Here, the equation for the current input to the i-th bus, that is, Ii, can be expressed by the conductance and the voltage of each bus as follows.

이다.Here, Gij = -g _ij (i? J), and Gii =

to be.

In the above equation (1), the conductance component G indicated by an upper case letter is an element of the conductance matrix as follows. For example, assuming that the distribution system of this embodiment is composed of three buses in total, the conductance matrix in the distribution system consisting of three buses in total is as follows.

The relationship between voltage and current can be expressed as follows.

That is, when I express it as a matrix, I = G _bus · V.

의 전류식을 찾을 수 있다.From Equation 1,

Can be found.

The power input to the i-th bus of the distribution system having N buses can be expressed by Equation (2).

At this time, partial derivatives of the following equations (3) and (4) can be obtained from the equation (2), respectively.

Here, the reciprocal of the equations (3) and (4) is the voltage sensitivity index (VSF).

That is, the VSF is obtained by the following equations (5) and (6).

Equation (5) represents the voltage fluctuation sensitivity of the jth bus when the distributed power of the i < th > bus fluctuates, and Equation (6) represents the voltage fluctuation sensitivity of the i < th > Here, Vi is the voltage of the i-th bus, Gij is the inductance between the i-th bus and the j-th bus, and Vj is the voltage of the j-th bus.

When the VSF index is obtained for each of the plurality of distributed power sources, the central controller 210 transmits a control command to the intelligent agent 150 to control the power generation amount of the distributed power source connected to the intelligent agent 150. Each of the intelligent agents 150 receiving the control command controls the amount of power generated by the distributed power sources, i.e., the power source 110 and the energy storage device 130 connected to the intelligent agent 150 according to the control command. At this time, it is possible to regulate the generation amount of the dispersed power source in the order of high VSF.

While the present invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not limited to the disclosed embodiments. That is, within the scope of the present invention, all of the components may be selectively coupled to one or more of them. Furthermore, the terms "comprises", "comprising", or "having" described above mean that a component can be implanted unless otherwise specifically stated, But should be construed as including other elements. All terms, including technical and scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs, unless otherwise defined. Commonly used terms, such as predefined terms, should be interpreted to be consistent with the contextual meanings of the related art, and are not to be construed as ideal or overly formal, unless expressly defined to the contrary.

The foregoing description is merely illustrative of the technical idea of the present invention, and various changes and modifications may be made by those skilled in the art without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are intended to illustrate rather than limit the scope of the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The scope of protection of the present invention should be construed according to the following claims, and all technical ideas within the scope of equivalents should be construed as falling within the scope of the present invention.

10: Distribution line 20: AC / DC converter
110: Power source 120: Load
130: Energy storage device 140: Power conversion device
150: intelligent agent 210: central controller

Claims (13)

Detecting a distribution voltage at a location where a plurality of intelligent agents installed in a distribution line of a low voltage direct current (LVDC) distribution system is located and transmitting the detected distribution voltage to a central controller;
Checking whether the distribution voltage fluctuates at each of the points from the distribution voltage detection values transmitted from the intelligent agents at the central controller;
Transmitting a control command to the intelligent agent to adjust the magnitude of the output voltage converted by the power converter at the point in the central controller when a variation in the distribution voltage occurs at each point; And
Controlling the magnitude of the power-converted output voltage by controlling the operation of the power conversion apparatus connected to the intelligent agent receiving the control command; (LVDC) power distribution system. The method according to claim 1,
Wherein the central controller transmits a control command to the intelligent agent when the variation of the detected voltage at each point is out of the predetermined reference voltage range. The method according to claim 1,
Wherein the conversion width of the power conversion device is determined according to the variation width of the distribution voltage. The method according to claim 1,
After adjusting the magnitude of the power-converted output voltage,
Determining whether a distribution voltage at each of the points has returned to a predetermined normal range based on a detection value of a distribution voltage of each point to the distribution line transmitted from each intelligent agent at the central controller;
Transmitting a control command for controlling the amount of power generated by the distributed power source to the intelligent agent when the determination result does not return to the normal range;
Adjusting an amount of power generation of the distributed power supply in each intelligent agent that receives the control command; Further comprising a power distribution system in a low voltage direct current (LVDC) power distribution system. 5. The method of claim 4,
Wherein the power generation amount of the distributed power source is determined according to the difference between the detection value of the distribution voltage at each point and the normal range. 5. The method of claim 4,
The step of regulating the power generation amount of the distributed power source
Wherein the power generation amount is regulated in the order of a distributed voltage power source having a high voltage sensitivity index (VSF) if it is determined that the distribution voltage does not return to the normal range at the plurality of points. The method according to claim 6,
If the low voltage direct current (LVDC) distribution system has a total of N busses
When the power generation amount of the distributed power of the i-th bus fluctuates, the voltage sensitivity index (VSF) according to the voltage variation of the j-th bus is expressed by the following equation,

And
The voltage sensitivity index (VSF) according to the voltage variation of the i-th bus is expressed by the following equation,

(LVDC) distribution system calculated as: < RTI ID = 0.0 >
(Vi: voltage of the ith bus, Gij: inductance between the ith bus and the jth bus, and Vj: voltage of the jth bus) In a low voltage direct current (LVDC) power distribution system including multiple distributed power sources and loads,
A plurality of power converters respectively installed on the power distribution lines of the low voltage direct current (LVDC) power distribution system to perform power conversion in front of the distributed power sources;
A plurality of intelligent agents connected to the respective power conversion devices on the power distribution lines for detecting power distribution voltages at their own points and controlling operations of the power conversion devices connected to the power conversion devices according to control commands received from a higher level; And
Wherein the control unit determines whether the distribution voltage fluctuates for each of the points from the distribution voltage detection values received from the intelligent agents and if the distribution voltage fluctuates for each of the points, A central controller for sending a control command to each of the intelligent agents to control the intelligent agent; (LVDC) power distribution system. 9. The method of claim 8,
Wherein the intelligent agent controls the operation of the power conversion device connected to the intelligent agent to adjust the magnitude of the power converted output voltage in accordance with the variation of the distribution voltage of each point according to the control command received from the central controller, (LVDC) distribution system. 9. The method of claim 8,
Wherein the central controller transmits a control command to the intelligent agent when the variation of the detected voltage at each point exceeds a predetermined reference voltage range. 9. The method of claim 8,
The central controller returns the distribution voltage at each point to a predetermined normal range based on the detection value of the distribution voltage of each point to the distribution line transmitted from each intelligent agent after transmitting the control command to the intelligent agent. (LVDC) power distribution system for controlling the generation amount of the distributed power supply to each of the intelligent agents when it is not returned to the normal range. 12. The method of claim 11,
Wherein the intelligent agent controls the amount of power generation of the distributed power supply according to a control command received from the central controller. 13. The method of claim 12,
Wherein the central controller sends control commands to the intelligent agent to regulate the power generation in the order of distributed power sources having a high voltage sensitivity index (VSF).

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