JPH07170662A - Method and device for minimizing power distribution system loss - Google Patents

Abstract

PURPOSE:To provide a method and device for switching a system for minimizing the power loss of a power distribution system in real time. CONSTITUTION:A power distribution system loss-minimizing controller provided at a power distribution automation device previously obtains a constantly open switcher which is in a configuration for minimizing power loss at adjacent power distribution lines 1' and 2', namely which becomes a linkage point, based on a current distribution 3 according to a load ratio and then stores it in a tabular form. The controller periodically measures, on-line, feeder current [1 and [2 of the power distribution lines 1' and 2' to obtain a load ratio and then performs switching control when the constantly open switcher differs from the previous time by referring to the correspondence table. The table is created again when the power distribution facility data are maintained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a distribution automation system, and more particularly to a distribution system loss minimum system switching control system which minimizes transmission loss of the distribution system.

[0002]

2. Description of the Related Art Minimization of transmission loss is one of the most important issues in securing a stable supply for an ever-increasing power demand.

As a method of minimizing the power loss of the distribution system, the power flow calculation is performed for the distribution system when all the switches of the distribution system are in the closed state, and the passing current of the switch is minimized based on the current distribution. The system to open the switch is determined, then the power flow is calculated again for each of the calculated systems to determine the switch to be opened, and this is repeated in sequence until all distribution lines are in the dendritic state. A method of repeatedly obtaining a loss minimum line is known.

Further, as described in Japanese Patent Laid-Open No. 4-210735, the power loss is calculated by sequentially moving the interconnection points between the distribution systems of interest, and the system configuration at the interconnection point where the loss is minimized. There is a proposal to adopt.

[0005]

However, in order to find a system configuration with a minimum transmission loss for a distribution system of a huge amount of equipment that spreads in a dendritic or mesh-like manner, the conventional technique requires several minutes to several minutes. A huge amount of calculation is required for every sufficient control. Therefore, the load on the distribution automation system is heavy, and it is difficult to apply it to real-time control based on online load information.

Although the method of the above cited example is one step ahead in the point of being based on the online load information, it requires a huge amount of sum of products calculation to obtain the power loss each time, and the load on the distribution automation system is burdened. large. In particular, almost all of the existing distribution lines do not have the function of detecting the section current of the distribution lines, so the applicable distribution system must be extremely limited.

[0007] Furthermore, in order to execute the online minimum loss control, it is necessary to cooperate with the conventional supervisory control and operation by the distribution automation system, but in the configuration of the conventional minimum loss system, these must be considered. Can not be seen.

A first object of the present invention is to provide a loss minimum control method and apparatus which can easily determine a loss minimum system based on an online load to enable real-time control and can be applied to all power distribution systems. Especially.

A second object of the present invention is to provide a loss minimum control method and apparatus which can limit the online loss minimum system and maintain stable operation of the power distribution system.

A third object of the present invention is to provide a distribution automation system which is equipped with a loss minimum control device capable of cooperating with a normal distribution system monitor and control device and which is easy to maintain.

[0011]

The first object mentioned above is
In loss minimum system switching control of a distribution system, achieved by the first invention, which controls switching of a normally open switch that connects the two distribution lines so that the online loads of the two distribution lines are most equalized. To be done.

That is, a normally open switch which is connected to the feeder via a plurality of switches and which connects two distribution lines for supplying power to the load is selected from the plurality of switches to reduce distribution loss. In loss minimum control of the distribution system that performs switching control so as to be set, a correspondence table between the load ratio of the two distribution lines and the plurality of switches that minimizes distribution loss is preset for each of the two distribution lines that are interconnected. Then, the feeder current of the two distribution lines is measured online to obtain the load ratio, and the normally open switch adapted to the online load ratio is selected according to the correspondence table.

The above-mentioned second object is configured so that a plurality of distribution lines interconnected via a normally open switch is interconnected with another distribution line via another normally open switch. In loss minimum control of a distribution system, when a given distribution line is connected or connected to other distribution lines or branch lines of distribution lines via multiple normally open switches, the distribution line is most As a one-to-one contiguous distribution line group, which is considered to have no interconnection with other normally open switches, limited to connection with normally open switches that are interconnected with other distribution lines or branch lines that have a large load. It is achieved by the second aspect of the present invention, in which the normally open switch of the adjacent distribution line set is switched and controlled in accordance with the measured online load so as to minimize the distribution loss of the adjacent distribution line set.

The other distribution line or branch line having the largest load is selected to have the largest number of switches.

A third object of the present invention is to provide a distribution automation system which monitors and controls distribution systems of a plurality of substations via a remote monitoring and control device, monitors abnormalities of the distribution system, and controls switching of the distribution system when there is an abnormality. And a distribution system monitoring and control device that supplies power to the load through another route, and a switching system that minimizes the load ratio and distribution loss of the two distribution lines for every two distribution lines that are adjacent and interconnected in the distribution system. The correspondence relation table with the switch is set in advance, the feeder current of the distribution line is measured online to obtain the load ratio of the two distribution lines, and the normally open switch adapted to the online load ratio is corresponded to the above. It is equipped with a distribution system loss minimum control device that performs switching control of the two distribution lines by selecting from the relational table, and the abnormal control by the distribution system monitoring control device is controlled by the switching control of the distribution system loss minimum control device. Configured to perform in preference to, it is achieved by the third aspect of the present invention.

The distribution system loss minimum control device is provided with a correspondence relationship table creating means for resetting the correspondence relationship table when the distribution facility data of the distribution system is changed.

[0017]

According to the first aspect of the present invention, only the load ratio of the two distribution lines to be interconnected is obtained from the feeder current measured online, and the interconnection point that minimizes the power loss of the two distribution lines, That is, the normally open switch can be determined.

Corresponding to the loss-minimum normally open switch according to the load ratio, the load distribution when the load ratio of the two distribution lines to be interconnected is changed is obtained from the section load apportioning coefficient based on the contracted electric energy, The interconnection points that minimize the distribution loss in the load distribution are obtained by a power flow calculation method, etc., and tabulated.

According to this, the present invention can be applied to the existing distribution system in which the real-time loss minimum control can be executed very easily and the load distribution cannot be measured.

According to the second aspect of the present invention, the set of two distribution lines for performing the loss minimum control in the power distribution system can be limited, so that the loss minimum control in the entire power distribution system can be executed stably and at high speed, and in terms of operation. The confusion of can be avoided.

According to the third aspect of the invention, the loss minimum control is prioritized for monitoring and controlling the power distribution system at the time of an abnormality, so that the coordinated operation of the power distribution system automation system can be ensured and the power distribution equipment can be flexibly changed. Can handle.

[0022]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIG. 1 is an explanatory view for conceptually explaining the first invention, showing a basic configuration of the adjacent distribution lines and a loss minimum configuration of the adjacent distribution lines according to the load ratio.

The adjacent two distribution lines are, as shown in FIG. 2A, a switch 2-1 and a switch 2 which are normally closed (normally closed) from the breaker (FCB) 1-A of the substation feeder A. -2 to switch 2-3 which is normally open (normally open) and breaker (FCB) 1-B of substation feeder B to switch 2-5 which is always closed (normally closed) , Switch 2-4
And a distribution line up to a switch 2-3 that is normally open (normally open). Here, the normally open switch 2-3
Is also called the interconnection switch because it is the interconnection point of both distribution lines.

A line divided by a switch in a distribution line is called a section. Usually, the load amount of each section is set so as to balance the contracted power amount while taking into consideration the number of customers and large-scale customers. Therefore, the load distribution ratio of the contract load amount of each section to the total contract load amount (contract feeder current) becomes a value determined for each distribution line, and is shown as a section load apportioning factor. Unless the distribution facility is changed, the section load apportionment factor is substantially the same as the actual load distribution rate of each section in the distribution line even if the online feeder currents I ₁ and I ₂ change with time.

In the power distribution system, such adjacent power distribution lines are the minimum unit, and a large number of power distribution lines are configured in a dendritic or mesh pattern via interconnection switches (normally open switches).
It carries the power supplied from Da to the customers. Power supply rule
To change the switch, turn on the normally open switch and open one of the normally closed switches.

Conventionally, the normal power supply route has been fixedly operated. However, the power loss of the distribution line is caused by "(passing current) ² × line resistance", so if the power supply route is properly selected according to the load distribution in the time zone,
Distribution loss in the system can be minimized. In the following, a distribution system that minimizes distribution loss will be referred to as a loss minimum system, and switching control therefor will be referred to as distribution system loss minimum control.

FIG. 1B shows an example of the configuration of the loss minimum system in the time zone in which the load distribution 3 is biased to the distribution line, and the load on both distribution lines is equalized by the loss minimum control of the present invention. Thus, the switch 2-3 is normally closed and the switch 2-2 is controlled to be normally open. Compared to the system of FIG. 9A, the power supply range of the distribution line is reduced and the power supply range of the distribution line is increased. In the same figure (c), the switch 2-4 is controlled to be normally open in the loss minimum system in the time zone when the load distribution 3 is biased to the distribution line.

In the present invention, the fact that the section load apportionment factor substantially matches the online load distribution is used to determine the load ratio for each adjacent distribution line in advance from the load ratio and the section load apportionment factor of two adjacent distribution lines. Find the corresponding interconnection point. After that, the interconnection point is switched and controlled according to the load ratio measured online to minimize the power loss in the two distribution lines,
This is done for two adjacent distribution lines in the entire distribution system.

FIG. 2 is an embodiment relating to all of the first, second and third inventions, and shows the overall configuration of the distribution automation system. The distribution system loss minimum control device of the present embodiment is incorporated in an existing distribution automation device, and performs real-time configuration control of the loss minimum system for each set of two adjacent distribution lines in the distribution system.

In the figure, the distribution automation device 11 installed in each business office monitors and controls each substation within the business office via remote monitoring control devices (distance control) 14 and 15. The maximum number of substations in the pipe is about 30-40. A maximum of three distribution transformers 16 are installed in one substation, and play the role of a power source for supplying power to the distribution line from a transmission line (not shown).

The distribution transformer 16 supplies electric power to a distribution line that is normally connected by a plurality of switches 18 via a substation feeder breaker (FCB) 17 of up to 10 transformers. Each switch 18 has a switch control device 19 for controlling its opening and closing, a switch communication device 20 for periodically sending and receiving an open / close control command signal and a switch status signal to and from the substation remote control 15, and these signals. There is provided a communication line 21 for transmitting the signal and a feeder current detector 22 for detecting the feeder current of each distribution line. The substation remote control 15 periodically samples the detection value of the current detector 22.

Although there has been a small amount of each switch 18 equipped with a current detection function to detect a load current in a section recently, most existing distribution systems do not have such a current detection function.

The distribution automation device 11 monitors the accident of the distribution system in the sales office, and switches the distribution system when necessary to control the distribution system to secure power supply, and the distribution system loss minimum according to the present invention. The control means 12 is provided to execute the supervisory control and the loss minimum control in real time for a large number of power distribution systems within the sales office. for that reason,
It is necessary to execute the loss minimum control at high speed and stably so that the processing of the distribution system monitoring control means 13 is not hindered.

FIG. 3 shows a power distribution system loss minimum controller 1.
It is a functional block diagram which shows the detailed structure of 2. The feeder current fetching unit 31 determines the feeder current measuring device 22 of the corresponding distribution line according to the setting of the adjacent distribution line set table 37.
Is sampled and the measured value of the feeder current is captured.
The feeder current ratio monitoring unit 32 calculates the ratio α (%) of the measured values of the feeder currents of the two adjacent distribution lines by using (Equation 1).

[0036]

[Equation 1] α = I ₂ / (I ₁ + I ₂ ) × 100 where I _{1 is} the feeder current value of the distribution line of the adjacent distribution line set I _{2 is} the feeder current value of the distribution line of the adjacent distribution line set Loss minimum system The determining unit 33 refers to the system switching switch table 39 and determines the system switching switch corresponding to the feeder current ratio α as the normally open switch of the adjacent distribution line system.

FIG. 4 shows a system switching switch table 39.
Regarding the example of the distribution line and the adjacent distribution line set including the distribution line shown in FIG. 2, the range of the feeder current ratio α when the switches 2-1 to 2-5 are normally opened is set.

The system switching procedure creation unit 34 creates a loss minimum control command instructing a switching procedure for constructing a new loss minimum system. The control command is composed of a normal close command for the current normally open switch, confirmation of the switching, and a normally open command for a new interconnection switch output after the confirmation.

The loss minimum control command output section 35 confirms the presence or absence of a distribution system abnormality signal from the outside such as the distribution system monitoring control means 13, and when there is no abnormality in the distribution system,
The switch control device 19 is operated via the branch control 14 for the business office and the control 15 for the substation to open / close the corresponding switch.

FIG. 5 shows a power distribution system loss minimum control device 1
It is a flowchart which shows the process procedure of 2. This control is
It is activated every few minutes to tens of minutes. As shown,
Calculate the feeder current ratio α of adjacent distribution line pairs (s10
2) A normally open switch that covers this ratio α is obtained by searching the system switching switch table 39 (s103). Further, it is determined whether the obtained normally open switch and the previously (currently) normally open switch are different (s104), and if they are the same, the process ends. If they are different, a loss minimum control command is created (s105), and when there is no accident related to the system (s106), the loss minimum control command is output (s10).
7), switching control of the adjacent power distribution group.

The check of the presence or absence of an accident in step s106 gives priority to the control by the distribution system monitoring control means 13,
This is a measure for coordinating system monitoring control and loss minimum control, and is not an essential process for loss minimum control. Needless to say, if priority control is systematized in the distribution automation device 11, it can be omitted.

FIG. 6 is a flow chart for creating the system switching switch table 39 by the loss minimum system switching switch table creation unit 38. This processing is performed by the adjacent distribution line set table 37 by the adjacent distribution line set creation unit 36 described later.
Is executed every time it is updated.

First, for one of the adjacent distribution line sets set in the adjacent distribution line set table 37, the load ratio of both distribution lines is initialized (s201). Here, the load ratio is the ratio of the feeder current and corresponds to the feeder current ratio α according to the actually measured value shown in (Equation 1). The initial value of the load ratio that is set is arbitrary, but is, for example, 5%.

Under this load ratio condition, the loss minimum system of the two distribution lines, that is, the interconnection point (normally open switch) that minimizes the power loss is obtained (s202). The solution of the loss minimum system is performed by the conventional power flow calculation method described above, or the method of calculating the power loss in the reference example (Japanese Patent Laid-Open No. 4-210735).

In this case, the feeder current of the distribution line having the higher load ratio is used as the rated value, and the load distribution of each section is determined by the section load distribution coefficient of each distribution line. In this embodiment, according to the range of the load ratio of the two adjacent distribution lines,
The loss minimum system of the two distribution lines is uniquely determined. Therefore, it suffices to know the load distribution ratio in the two distribution lines,
The absolute value of the load is not directly related to the determination of the system, and the above rated value and the like are given for the convenience of calculation.

Next, it is judged whether or not the normally open switch which is the interconnection point obtained at step s202 and the normally open switch obtained at the previous load ratio are different (s203). And the normally open switch are paired and stored in the system switching switch table 39 (s204). Then, check whether the current load ratio exceeds the maximum value, for example, 95% (s
205), if not exceeded, increase by a predetermined ratio, for example 5% (s206), and repeat the above steps,
A correspondence table of switching switches and load ratio ranges that minimizes the two distribution lines, that is, a system switching switch table 39 is created. Further, the system switching switch table 39 is created for all the adjacent distribution line sets set in the adjacent distribution line set table 37 (s207), and the process ends.

FIG. 7 exemplifies the daily fluctuation pattern of the feeder current ratio in the adjacent distribution line shown in FIG. 2 and the execution situations (a) to (d) of the loss minimum control. The normally open switch is switched from 2-2 to 2-3 at point (a) and from 2-3 to 2-4 at point (b). At point (c), it is 2-4 ⇒ 2-3 again, and at point (d) it is 2-3.
=> Switched to 2-2.

According to the present embodiment, the load distribution of each section obtained by the section load apportioning factor is almost the same as the online load distribution, so that the online load ratio ( The loss minimum system corresponding to the measured feeder current ratio) can be obtained. Therefore, it can be widely applied to the existing distribution system that does not have the section load measuring equipment.

Of course, when the load distribution of each section of the two distribution lines is greatly different from the proportional distribution coefficient at a specific time zone or day of the week, and the load distribution rate can be estimated in advance, the load distribution for each time zone or day of the week Alternatively, the adjacent minimum distribution line group table 37 may be created by obtaining the loss minimum system based on the load distribution ratio, and the adjacent distribution line set table 37 may be selected according to the online time zone or day of the week.

Further, when the section load of the distribution system can be measured, a plurality of patterns of the adjacent distribution line set table 37 in which both the load ratio of both distribution lines and the load distribution rate of each section are changed are created, and online. An approximate pattern may be selected according to the feeder current and the measured value of each section current.

With these, the accuracy of the loss minimum control executed in real time can be further improved.

FIG. 8 and FIG. 9 show typical patterns of the distribution system. In an actual power distribution system, not only two adjacent distribution lines have a one-to-one correspondence (example of Fig. 1), but also the distribution line has a plurality of interconnection points, In many cases, it is connected to the branch line in a complicated manner.

In the example of FIG. 8, the distribution line from the FCB1-A through the switches 2-1 and 2-2 and the branch line from the switch 2-3 to the interconnection switch 2-5 and the switch 2 A branch line from -10 to the interconnection switch 2-11 is included. Further, the distribution line goes from the FCB 1-D to the interconnection switch 2-11 via the switches 2-13 and 2-12, and the switch 2-1.
It includes a branch line that branches from the section after 2 to the interconnection switch 2-16 via the switch 2-17. In the example of FIG. 9, the distribution line is FCB1-E and the distribution line is FCB1-F.
Corresponding to, but a plurality of interconnection switches 2-22, 2-2
Each distribution line is branched by 8.

In this way, in a system in which there are a plurality of distribution lines and branch lines adjacent to each other through a plurality of interconnection points,
It is not always good practice to perform the loss minimum control of the present invention for all combinations.

For example, in the distribution line of FIG. 8, there are distribution lines and distribution lines as adjacent distribution lines. First, when loss minimum control is performed on distribution lines and distribution lines to change the interconnection points, and then loss minimum control is performed on distribution lines and distribution lines to change interconnection points, the distribution lines and distribution lines It becomes necessary to perform the loss minimum control of, and in order to obtain the optimal solution through such repetition, considering the dendritic or mesh-like connection of the distribution line,
Even if it is cut off with an appropriate number of repetitions, a huge amount of calculation is required, and the number of switching controls increases due to the influence of adjacent distribution lines.

In addition, when the loss minimum control is performed for all the combinations, the chaotic interconnection points are frequently changed over all the distribution lines that are adjacent to each other, so that the operation of the distribution automation system is confused and the operators are confused. It will be difficult to recognize the current status of the distribution system. As a result, there is a possibility that inconvenience may occur in dealing with a system abnormality or emergency.

According to the second aspect of the present invention, the combination of adjacent distribution lines for which the loss minimum control is performed is aggregated into branch lines having a large load, and the number is limited to one for each distribution line. The branch line with a lot of load is
Select the switch with the largest number of switches from the FCB to the interconnection point or from the FCB to another FCB.

FIG. 10 shows an embodiment of the second invention and is a flow chart for selecting a set of two adjacent distribution lines from the distribution system. This processing is executed by the adjacent distribution line set creation unit 36 shown in FIG. 3 when the distribution facility data is changed. In addition, the distribution facility data indicating the distribution system facilities and the connection relationship between them is the distribution automation device 11 shown in FIG.
It is stored in a database (not shown) and is maintained as power distribution equipment is changed.

First, for one of the distribution lines in the distribution system connected to the same distribution transformer 16, it is judged whether there are a plurality of normally open switches connected to the distribution line (s30).
1). If there is one normally open switch, the switch is stored as an adjacent candidate switch of the self-distribution line (s302). Figure 8
Distribution line and switch 2-5, distribution line and switch 2-16
Is equivalent to

If there are a plurality of switches in step s301,
It is determined whether there are a plurality of other distribution lines connected by those switches (s303). If there is one other distribution line, the branch line normally open switch with the largest number of switches in the distribution line and other distribution lines is the adjacent candidate switch for the distribution line and other distribution lines. (S304). The distribution line in FIG. 9 corresponds to the distribution line and the switch 2-22.

In step s103, if there are a plurality of distribution lines, the branch line normally open switch with the largest number of switches is automatically connected to each of the plurality of normally open switches from the power supply side of the own distribution line. The data is stored as an adjacent switch of the distribution line (s305). Figure 8
Distribution line and switch 2-5, distribution line and switch 2-16
Is equivalent to

After the above processing is performed for all distribution lines in the distribution system (s306), distribution lines having the same adjacent candidate switch are extracted as adjacent distribution line groups and set in the adjacent distribution line group table 37. Yes (s307). In the example of FIG. 8, a switch 2-5 sets an adjacent distribution line and a set of distribution lines, and a switch 2-16 sets an adjacent distribution line and a set of distribution lines in the table 37. Further, in the example of FIG. 9, the switch 2-22 sets a pair of adjacent distribution lines and distribution lines.

In step s307, if another distribution line having the same adjacent candidate switch as the own distribution line is not extracted, the adjacency relation with another similar distribution line is determined, and those having the adjacency relation are judged. By extracting, it is possible to select adjacent distribution line groups for all distribution lines.

FIG. 11 shows an example of adjacent distribution line pairs selected in this embodiment. This is an example of the distribution line in FIG. 8, and it is considered that there is no adjacency relationship with the distribution line and is limited to the one-to-one adjacency relationship between the distribution line and the distribution line. Similarly, the distribution line of FIG. 8 is limited to the adjacent relationship with the distribution line.

By applying the loss minimum control of the first invention to only one set of adjacent distribution lines limited in this way, the calculation for obtaining the loss minimum system is speeded up,
Real-time processing can be easily realized. Further, as compared with the case where all the adjacency relations are targeted, the number of times of switching control due to load fluctuation can be reduced, so that stable control of the distribution system can be maintained. Furthermore, the switch that is switch-controlled has a predetermined 2
Since it is limited to the distribution line, stable operation of the distribution system is ensured, and operators can easily recognize the distribution system.

[0066]

According to the first aspect of the present invention, since the loss minimum system can be easily determined from the ratio of the online loads of the two adjacent distribution lines, real-time loss minimum control can be executed and the power loss of the distribution system can be greatly reduced. There is an effect that can be reduced. In particular, it can be applied to existing power distribution systems that do not have a section load measurement function.

According to the second aspect of the present invention, the adjacent distribution line group in the distribution system is limited so as not to overlap with others, so that the loss minimum control can be executed at high speed and stably, and the operation of the distribution system is hindered. Nothing.

According to the third aspect of the present invention, the conventional distribution automation system is equipped with the loss minimum control function so as to cooperate with the distribution system monitoring control function, so that the system configuration is easy and the distribution equipment can be changed. We can respond flexibly.

[Brief description of drawings]

FIG. 1 is an explanatory diagram illustrating the concept of loss minimum control of the present invention.

FIG. 2 is a schematic configuration diagram of a distribution automation control system according to an embodiment of the present invention.

FIG. 3 is a functional block diagram showing a configuration of a distribution system loss minimum control device.

FIG. 4 is a configuration diagram of a system switching switch table for setting a correspondence relationship between a normally open switch of a loss minimum system and a feeder current ratio.

FIG. 5 is a flowchart showing a processing procedure of a distribution system loss minimum control device.

FIG. 6 is a flowchart showing a processing procedure for setting a switching switch table.

FIG. 7 is an explanatory diagram illustrating a timing of loss minimum control corresponding to a daily variation pattern of a feeder current ratio.

FIG. 8 is an example of a typical pattern of a power distribution system.

FIG. 9 is another example of a typical pattern of a distribution system.

FIG. 10 is a flowchart showing a procedure for selecting an adjacent distribution line set.

FIG. 11 is an example of a configuration of adjacent distribution line groups selected and limited.

[Explanation of symbols]

1, 17 ... Substation feeder breaker (FCB), 2, 1
8 ... Switching switch, 11 ... Distribution automation device, 12 ... Distribution system loss minimum control means, 13 ... Distribution system monitoring control means, 14 ... Distance monitoring control device for business office, 15 ... Distance monitoring control device for substation, 16 ... Distribution Transformer, 19 ... Switch control device, 22 ... Feeder current measuring device, 31 ... Feeder current intake section, 32 ... Feeder current ratio monitoring section, 33 ...
Loss minimum system determination unit, 34 ... System switching procedure creation unit,
35 ... Loss minimum control command output unit, 36 ... Adjacent distribution line set table creation unit, 37 ... Adjacent distribution line set table, 38
… Loss minimum system switchgear table creation unit, 39…
System switching switch table.

Claims (16)

[Claims] 1. A normally open switch (hereinafter, normally open switch) which is connected to a feeder through a plurality of switches and interconnects two distribution lines which supply power to a load. In the loss minimum control method for a distribution system, which is selected from among the above, and is switch-controlled so as to reduce distribution loss, the two distribution lines are interconnected so that the online loads of the two connected distribution lines are most equalized. A loss-minimum control method for a power distribution system, which comprises selecting a normally open switch to be used. 2. A normally open switch, which is connected to a feeder via a plurality of switches and interconnects two distribution lines for supplying power to a load, is selected from the plurality of switches to reduce distribution loss. In the loss minimum control method of the distribution system for performing switching control so as to perform, a correspondence table between the load ratio of the two distribution lines and the plurality of switches that minimizes distribution loss is previously set for each of the two distributed distribution lines. The distribution is characterized in that the feeder currents of the two distribution lines are set online to obtain the load ratio, and a normally open switch adapted to the online load ratio is selected according to the correspondence table. System loss minimum control method. 3. The correspondence table according to claim 2, wherein the correspondence table is set based on the load distribution when the load ratio of the two distribution lines connected to each other is changed so that distribution loss is minimized. A loss minimum control method for a distribution system, characterized in that a normally open switch to be connected is obtained by a power flow calculation method or the like. 4. The loss minimum of a distribution system according to claim 3, wherein the load distribution is estimated by a load ratio of the two interconnected distribution lines and a load distribution coefficient of each section of the distribution line. Control method. 5. The load distribution according to claim 3, wherein the load distribution adopts different patterns depending on a predetermined day of the week or a time zone, and the correspondence table is set for each of the predetermined day of the week and the time zone. Loss minimum control method for distribution system. 6. A distribution loss by selecting from the plurality of switches a normally open switch that is connected to a feeder through a plurality of switches and interconnects two distribution lines that supply power to a load. In a loss minimum control method for a distribution system that performs switching control so as to minimize, while changing the load ratio of the two distribution lines and the load distribution pattern of each section of the distribution line for each of the two distribution lines that are interconnected,
The correspondence table of the normally open switch with which the distribution loss is minimized is set in advance according to the load ratio and the load distribution pattern, and the feeder current and the section load of the two distribution lines are measured online and obtained. A loss minimum control method for a distribution system, wherein a normally open switch adapted to a load ratio and a load distribution pattern is selected according to the correspondence table. 7. A loss minimum control of a power distribution system configured such that a plurality of distribution lines interconnected via a normally open switch is further interconnected with another distribution line via another normally open switch. In the method, when a given distribution line is interconnected or connected to other distribution lines or branch lines of the distribution line through a plurality of normally open switches, the distribution line is not The connection is limited to the normally open switch that is connected to the distribution line or the branch line, and is set as a one-to-one adjacent distribution line group that is considered not to be connected to other normally open switches. A loss minimum control method for a distribution system, characterized by switching and controlling a normally-open switch of an adjacent distribution line set according to a measured online load so as to minimize distribution loss of the distribution line set. 8. The loss minimum control method for a power distribution system according to claim 7, wherein the other distribution line or branch line having the largest load is selected to have the largest number of switches. 9. The adjacent distribution line set according to claim 7 or 8, wherein a table is set for all distribution lines in a predetermined distribution system, and maintenance is performed when the distribution facility of the predetermined distribution system is changed. A loss minimum control method for a power distribution system, which is characterized by the following. 10. The switching control of the normally open switch of the adjacent distribution line group according to claim 7, 8 or 9, wherein the feeder current measured online of the two distribution lines is equalized to the most equal value. A loss-minimum control method for a power distribution system, wherein the switch is selected from the switches provided in the power distribution line. 11. The correspondence control table according to claim 7, 8 or 9, wherein the switching control of the normally open switch of the adjacent distribution line set is made between the load ratio of the two distribution lines and the switch having the minimum distribution loss. Is set in advance, a feeder current of the two distribution lines is measured online to obtain a load ratio, and a normally open switch adapted to the online load ratio is selected according to the correspondence table. Loss minimum control method for distribution system. 12. A plurality of distributors connected to a feeder of a distribution transformer via a circuit breaker and supplying power to a load via a plurality of normally-closed switches (hereinafter, normally-closed switches). In a loss minimum control device of a power distribution system in which a power line and a power distribution line adjacent to each other are interconnected by a normally-open switch, a feeder current measuring unit for online measuring the feeder current of each power distribution line, and the inside of the power distribution system Adjacent distribution line group table for presetting a pair of adjacent two distribution line groups, and for each two distribution lines of the adjacent distribution line group table, the load ratio and distribution loss of the two distribution lines are minimized. A storage device having a switching switch table that presets a correspondence table with open / normally closed switches, and a load ratio by the feeder current measured online for every two distribution lines of the adjacent distribution line set table To Because,
A loss-minimum control device for a power distribution system, comprising: a normally open switch adapted to the load ratio, which is determined according to the correspondence table, and a normally open switch switching control means for switching the switch. 13. The load distribution when changing the load ratio of two distribution lines for each two distribution lines of the adjacent distribution line group table according to claim 12, wherein the distribution ratio is minimized based on the load distribution. A loss minimum control device for a power distribution system, which is provided with a loss minimum system switching switch table creating means for seeking a normally open switch for connecting electric wires. 14. The method according to claim 12 or 13, wherein a predetermined distribution line in the distribution system is interconnected or connected to a plurality of other distribution lines via the plurality of normally open switches. One pair, which is considered to have no interconnection with other normally open switches, by limiting the predetermined distribution line to interconnection with a normally open switch that is interconnected with another distribution line with the largest number of switches. A loss minimum control device for a power distribution system, which is provided with an adjacent distribution line set table creating means set as one adjacent distribution line set. 15. A distribution automation system for monitoring and controlling a distribution system of a plurality of substations via a remote monitoring and control device, wherein an abnormality of the distribution system is monitored, and when there is a problem, the distribution system is switched and controlled by another route. 2 for each distribution system monitoring and control device that supplies power to the load, and for every 2 distribution lines that are adjacent to and interconnect with each other in the distribution system.
A correspondence table between the load ratio of the distribution line and the switch that minimizes the distribution loss is set in advance, the feeder current of the distribution line is measured online, and the load ratio of the two distribution lines is calculated. A normally open switch adapted to the load ratio of the above is selected from the above correspondence table, and a distribution system loss minimum control device for performing switching control of the two distribution lines is provided. A distribution automation system, wherein the control is configured to be prioritized over the switching control of the distribution system loss minimum control device. 16. The distribution system loss minimum control device according to claim 15, further comprising a correspondence relationship table creating unit for resetting the correspondence relationship table when the distribution facility data of the distribution system is changed. Power distribution automation system.