JPH1066261A - Apparatus and method for automatic loop changeover of distribution line - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an automatic loop changeover apparatus, for a distribution line, in which a loop changeover is not made unavailable by a method wherein a loop distribution line is selected with reference to an input power-failure object section, a power failure section which is adjacent to a corresponding normally-open switch is moved to a phase-advance-side distribution line when a judgment result is bad. SOLUTION: A power-failure section is designated and input via a CRT input device 14, and every section switch is operated in the same manner as in conventional cases after a loop is judged to be good. When the loop is judged to be bad, an operation to reduce the voltage difference between both sides of a normally-open section switch 9 is performed. The voltage difference can be realized by reducing a phase angle difference. In addition, in order to reduce the phase angle difference, it is sufficient to shift the load of a delay-phase-side distribution line to an advance-phase-side distribution line. As a result, the phase difference between both sides of the normally-open section switch 9 is reported to a phase operation means 107 from a loop right-or-wrong judgment means 102.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a distribution line automatic loop switching device and a method thereof in power distribution line operation.

[0002]

2. Description of the Related Art A configuration for supplying power to general consumers will be described with reference to FIG. First, a transformer 2 with a secondary voltage adjusting tap is connected to a distribution substation 1 to a main bus 3, and the main bus 3 is connected to respective distribution lines 51, 42 via distribution line draw-out circuit breakers 41, 42. 52 are provided. A line switch 6 (6-1) is connected to the auxiliary bus 7.

[0003] Each of these distribution lines is connected to a normally closed switch SW1 (S
W1-1), SW2 (SW2-1), SW3 (SW3-1),
There is a SW4 and each distribution line is divided into multiple sections 8-1 (81-1), 8-
It is divided into 2 (81-2), 8-3 (81-3), 8-4 (81-4) and 8-5, and the end is connected to normally open switch 9 (9-1). I have. The other distribution substation 1-1 has the same configuration,
It is interconnected by a normally open switch 9 (9-1).

[0004] Each normally closed switch has a switch slave station 10-1 (11-
1), 10-2 (11-2), 10-3 (11-3), and 10-4, which are connected to a data transmission device 13 via a transmission line 12. 11-0 is a slave station for a distribution substation.

[0005] As described above, the distribution lines are circuit breakers 41 and 42 (hereinafter referred to as FCB) connected to the main bus 3 or line switches 6 (6-1) (hereinafter referred to as LS) connected to the auxiliary bus. Drawn out from the plurality of normally closed segment switches S
W1 (SW1-1) to SW4 (SW3-1) (hereinafter, normally closed V
S).

[0006] The distribution line is connected to other distribution lines via one or more normally open segmented switches (hereinafter referred to as normally open VS). The distribution line is operated in such a manner that it always receives power supply from only one determined FCB without taking a loop configuration. Therefore, in the middle of the distribution line,
When a power failure occurs in a portion (hereinafter, referred to as a section) between two VSs, a power failure also occurs on the load side (the portion located in the opposite direction to the power supply side) in the section.

[0007] For daily maintenance, the cables constituting the distribution lines are operated with a power outage for each section. For this reason, at the time of a power failure, in order to avoid a power failure in the load side section that occurs with this momentarily, a normally open VS connected to an adjacent distribution line is turned on to temporarily perform a loop operation, and then the loop operation is performed. An operation of opening the VS on both sides of the power failure target section is performed.

However, when the loop is closed, a loop current is generated which is proportional to the voltage difference between both sides of the normally open VS before the closing operation, and this value is added to the FCB passing current.
If the CB allowable value is exceeded, the FCB may be cut off due to an overcurrent and the entire distribution line may stop.

For this reason, the voltage difference between both sides of the normally open VS is measured just before the loop is turned on, and the loop current is calculated based on this value using the equation (1). This value and the current passing through the FCB are summed up, and the FCB current is calculated by equation (2).

(Equation 1)

When the value of I exceeds the FCB allowable value, loop switching is not performed, and when a power failure occurs in the section to be switched, the power is temporarily interrupted along with the load-side section, and then the normally open VS is turned on. A method of charging the load-side section where the power failure has occurred along with the above is employed.

The conventional method will be further described. The designation of the distribution line blackout section is designated by the operator using the CRT input device 14. Here, if the stop target section is designated as 8-4, this input is read into the stop target section input means 105 in the computer 100, passed to the loop distribution line selection means 106, and provided with the distribution line and the The normally open VS 9 to be executed is selected.

Next, the selected distribution line and the normally-open VS9 information and the current FCB current and the normally-open VS9 voltage on both sides are stored in the VS slave station 10-5, the transmission line 12, and the data transmission device 13.
And loop availability determination means 10 via data collection means 101
2 to make a loop availability determination.

If it is determined that a loop is possible, the following switch switching procedure is created and passed to the switch operating means 104, where the data transmission device 13, the transmission path 12, and the switch slave stations 10-3 and 10-4 are provided. , 10-5
The opening / closing operation of the SW3, SW4 and normally open switch 9 is performed via.

Procedure 1 Normally open VS9 input (loop input). Procedure 2 SW3 off (loop off). Procedure 3 Switch SW4 off (disconnect power failure section).

If the loop permission determining means 102 determines that the loop is not possible, the following switching procedure is created and passed to the switching operation means 104 in the same manner, and the data is transmitted to the data transmission device 13, the transmission path 12, the switch The closing or opening operation of SW3, SW4 and normally open switch 9 is performed via slave stations 10-3, 10-4 and 10-5.

Procedure 1 SW3 is turned off. Procedure 2 Turn on normally open VS9. Procedure 3 SW4 off.

[0017]

As described above, if it is determined that the loop is not possible, the current system causes a supply trouble in the section 8-5 (section on the load side of the section targeted for the power failure). From the viewpoint of stable power supply, improvement measures were desired. The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a distribution line automatic loop switching device and a method thereof in which loop switching is not disabled.

[0018]

According to a first aspect of the present invention, there is provided an automatic distribution line loop switching device, wherein a plurality of distribution lines belonging to two distribution substations are provided by a plurality of normally closed switches. The distribution line is extended while being divided into sections, and in a distribution line having a configuration in which each distribution line is loop-connected at a terminal via a normally-open switch at a connection point, a loop distribution line is input to a section targeted for a power failure. And a phase operation means for transferring the corresponding blackout section adjacent to the corresponding normally open switch to the phase leading side distribution line when the result of the determination is not possible.

According to a second aspect of the present invention, there is provided a method of automatically switching a distribution line, wherein distribution lines belonging to two distribution substations are extended while dividing the distribution line into a plurality of sections by a plurality of normally closed switches. In a distribution line having a configuration in which each distribution line is loop-connected at a terminal via a normally open switch at a connection point, a part of a load belonging to one distribution substation is connected to a connection point switch. By operating to shift to the other distribution substation side and reducing the phase angle on both sides of the interconnection point, the occurrence of overcurrent of the distribution line breaker that occurs at the time of loop switching is prevented.

According to a third aspect of the present invention, in the automatic distribution line switching method according to the second aspect, in order to reduce the phase angle on both sides of the interconnection point, the load between the banks is reduced via the secondary bus of the bank. The transition was made.

According to a fourth aspect of the present invention, in the automatic distribution line switching method according to the second aspect, in order to reduce the phase angle on both sides of the interconnection point, the secondary voltage of the bank is changed via a tap switching operation of the bank. To change it.

[0022]

FIG. 1 is a block diagram showing an embodiment of a distribution line switching apparatus and method according to the present invention. In FIG. 1, the same parts as those in FIG. The feature of the configuration in FIG. 1 is that the phase operation means 107 is provided, and when it is determined that the loop is not possible, the operation for reducing the voltage difference between both sides of the normally open VS 9 is performed.

Therefore, the operation is the same as the conventional method up to the operation of each VS after the power failure section is designated and input via the CRT input device 14 and the loop is determined to be possible. here,
If it is determined that the loop is not possible, the normally open VS9 is performed by the following method.
Operation to reduce the voltage difference between the two sides. The voltage difference can be realized by reducing the phase angle difference. Also, in order to reduce the phase angle difference, the load on the lagging phase distribution line may be transferred to the leading phase distribution line.

For this reason, the loop availability determination means notifies the phase operation means 107 of the phase difference on both sides of the normally open VS 9. Next, the phase operation means sets the following conditions (a)
Select combinations of distribution lines and switches that match (b) and (c).

(A) A combination of distribution lines that can be put into a loop. (B) The distribution line drawing current after the load transfer should not exceed the permissible value of the distribution line FCB. (C) The load transfer amount must be such that the required phase angle difference can be reduced.

FIG. 2 is a flowchart for the phase operation. First, in step S21, a combination of loop distribution lines for load transfer is selected. If a load switching section meeting the condition is found, a procedure for switching is generated next. Here, for convenience of explanation, normally open VS91, SW2-2
Are described as target sections 82-3 and 82-4.

In step S22, the voltage difference between both ends of the normally open VS91 is fetched, and in step S23, the loop current I _LOOP including the normally open VS91 is calculated. In step S24, the FCB passing current of the loop distribution line ( _IFCB = _IFCB + I). _LOOP ).
In Step S25 I _FCB is judged whether or not it is within the allowable range of FCB of the distribution line, the flow goes to step S26 if not within the allowable range intended for other combinations, repeating the process.

[0028] If I _FCB is within the allowable range in step S25, the load of the N time section adjacent to the normally open VS91 proceeds to step S27, sets that transferred to the phase advance side power line, the step S28 To calculate the voltage difference between both ends of the normally open VS9.

In step S29, the loop current in this case is calculated, and in step S30, the FCB passing current (I _FCB = I _FCB + I _LOOP ) of the loop distribution line is calculated. In Step S31 I _FCB it is judged whether or not it is within the allowable range of the FCB, which is a predetermined N times if not within the acceptable range repeat the steps S27 to S31. When N exceeds the preset maximum number of times Max, the process ends as abnormal. If _IFFCB is within the allowable range in step S31, a loop switching procedure is created in step S32.

As a procedure for switching the loads in the sections 82-3 and 82-4, an opening and closing operation is performed according to the following procedure. Procedure 1 Normally open VS91. Procedure 2 Open SW2-2. First, the above procedure is delivered to the switching operation means 104, and the ON / OFF operation of the normally open VS91 and SW2-2 is performed via the data transmission device 13, the transmission path 12, and the VS slave stations 11-4 and 12-2. .

Next, the voltage difference between both ends of the normally open VS 9 is again VS
The data is transmitted to the loop availability determination means 102 via the slave station 10-5, the transmission path 12, the data transmission device 13, and the data collection means 101, and the loop availability determination is performed. If it is determined that the loop is possible, the following procedure is created and handed over to the switching operation means 104, and after the loop input operation, the power distribution line switching target section 1-2 is uninterrupted, and the power distribution line stop target section 8 -4 is cut off.

Procedure 1 Normally open SV9 input (loop input). Procedure 2 SW3 off (loop off). Procedure 3 Switch SW4 off (disconnect power failure section).

FIG. 3 is a block diagram showing another embodiment of the automatic distribution line loop switching method. In FIG. 3, the same portions as those in FIG. The characteristic feature of the configuration of the present embodiment is that the computer is provided with a distribution line bank transfer means 108, and when it is determined that the loop is not possible, the operation for reducing the voltage difference between both sides of the normally open VS 9 is performed.

Accordingly, the section 8-4 for power failure is designated and input,
The operation up to the operation of each VS after it is determined that loop switching is possible is the same as the conventional method. If it is determined that the loop is not possible, an operation for reducing the voltage difference between both sides of the normally open VS 9 is performed by the following method. As described above, in order to reduce the phase angle difference, the operation of switching the load of the lagging phase side distribution line to the phase side distribution line is performed.

For this reason, the distribution line bank transfer means 108 is notified of the phase difference of the normally open VS 9. Distribution line bank transfer means 10
8 selects one or more distribution lines that meet the following conditions (a) and (b). FIG. 4 shows a flowchart of the distribution line bank transfer means.

(A) The bank current after bank transfer does not exceed the bank allowable value. (B) The amount of transition must be such that the required phase angle difference can be reduced.

First, in step S41, the N distribution line load (the load of the FCB 43) is switched to the bank (FCB 42) to which the phase leading distribution line belongs. In step S42, normally open V
The voltage difference between both ends of S9 is calculated, and then the loop current (I _LOOP ) is calculated in step S43.

In step S44, based on the calculated loop current (I _LOOP ), the FCB passing current ( _IFCB = _IFCB + I _LOOP ) of the loop distribution line is calculated.
At 45, it is determined whether the passing current is within the allowable range of the FCB breaker. If this is not within the allowable range, the above process is repeated a predetermined number of times, and if it is within the allowable range, a loop switching procedure is created in step S46.

Here, if a bank load switching distribution line meeting the conditions is found, the following switching procedure is generated. Here, for convenience of explanation, the description will be made assuming that the load of the distribution line FCB43 is transferred to the distribution line FCB42.

Procedure 1 LS6-1 input. Procedure 2 Enter LS6-2. Procedure 3 FCB43 off.

Next, the above procedure is passed to the switching operation means 104, and the data transmission device 13, the transmission line 12, the substation substation 11-
The ON / OFF operation of the FCB 43 and LS6-1 and LS6-2 is performed via 0 and 11-1.

Next, the voltage difference between both ends of the normally open VS 9 is VS
The data is transmitted to the loop availability determination means 102 via the slave station 10-5, the transmission path 12, the data transmission device 13, and the data collection means 101, and the loop availability determination is performed.

If it is determined that the loop is possible, the following procedure is created and delivered to the switching operation means 104. After the loop input operation, the power distribution line switching target section 8-5 is continuously and uninterruptedly operated. The target section 8-4 is separated.

Procedure 1 Normally open SV9 input (loop input). Procedure 2 SW3 off (loop off). Procedure 3 Switch SW4 off (disconnect power failure section).

FIG. 5 is a block diagram showing another embodiment of the distribution line automatic loop switching method. In FIG. 5, the same parts as those in FIG. The feature of the configuration of the present embodiment is that a bus voltage adjustment control means 109 is provided in a computer to reduce the voltage difference between both sides of the normally open VS 9.

Also in this embodiment, the power failure target section 8-
4 is specified and input, and each VS after it is determined that loop switching is possible
The operation up to is the same as the conventional method. Here, if it is determined that the loop is not possible, an operation for reducing the voltage difference of the normally open VS9 is performed by the following method.

Therefore, the voltage difference of the normally open VS 9 is notified to the bus voltage adjustment control means 109. Bus voltage adjustment control means 10
9 finds the tap change amount of the transformer that meets the following condition (a). FIG. 6 shows a flowchart of the bus voltage adjusting means. (B) The switching point voltage after the tap value is changed should be small, and the FCB current of the loop distribution line due to the loop current should not exceed the allowable value.

First, in step S61, a voltage difference between the normally open VS9 is acquired. In step S62, it is set that the tap of the bank to which the low voltage distribution line belongs is raised by N steps, and in step S63, the voltage difference of the normally open VS9 is calculated. In step S64, the loop current (I _LOOP ) in that case is calculated, and in step S65, the FCB passing current (I _LOOP ) of the loop distribution line is calculated.
_FCB = _IFCB + _ILOOP ).

In step S66, it is determined whether or not the FCB passing current is within the allowable range. If not, the process proceeds to step S67 to set the tap of the bank to which the high-voltage distribution line belongs by N steps. Then, in step S68, the voltage difference of the normally open VS9 is calculated.

In step S69, the loop current (I _LOOP ) in that case is calculated, and in step S70, the FCB passing current (I _FCB = I _FCB + I _LOOP ) of the loop distribution line is obtained. Next, in step S71, it is determined whether or not _IFFCB is within an allowable range. If it is not within the allowable range, the process ends after a predetermined number of times. If it is within the allowable range at step S71, a tap elevation value is set. .

The bus voltage adjustment control means 109 passes a tap control signal to the data transmission device 13 to transmit the tap control signals to the substations 11-0, 11
Raise and lower transformer taps through -1. If it is determined that the loop is possible, the following procedure is created, and the power distribution line switching target section 8-4 is connected to the power distribution line switching target section 8-5 without interruption.
Is performed.

Procedure 1 Normally open SV9 input (loop input). Procedure 2 SW3 off (loop off). Procedure 3 Switch SW4 off (disconnect power failure section).

[0053]

As described above, according to the present invention, 2
When switching loops between distribution lines belonging to one bank, the interconnection point switch was operated to shift the load between banks and reduce the phase difference on both sides of the loop point. The loop switching can be performed while keeping the load side section of the power supply uninterrupted.

[Brief description of the drawings]

FIG. 1 is a diagram showing an embodiment of a distribution line automatic loop switching device and a method thereof according to the present invention.

FIG. 2 is a flowchart of a phase operation process of FIG. 1;

FIG. 3 is a diagram showing another embodiment of the distribution line automatic loop switching method according to the present invention.

FIG. 4 is a flowchart of a distribution line bank transfer process of FIG. 3;

FIG. 5 is a diagram showing still another embodiment of the distribution line automatic loop switching method according to the present invention.

FIG. 6 is a flowchart of a bus voltage adjustment control process of FIG. 5;

FIG. 7 is a diagram illustrating a conventional method.

[Explanation of symbols]

 1,1-1 Distribution substation 2,21 Transformer with secondary voltage adjustment tap 3 Main bus 41,42 Distribution line draw-out circuit breaker 51,52 Distribution line 6,6-1,6-2 Line switch 7 Auxiliary bus 8 section 9 normally open switch 10, 11 switch slave station 12 transmission line 13 data transmission device 14 CRT input device 100 computer 101 data collection means 102 loop availability determination means 103 switching procedure creation means 104 switching operation means 105 Stop target section input Means 106 Loop distribution line selection means 107 Phase operation means 108 Distribution line bank transfer means 109 Bus voltage adjustment control means

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Toshikazu Okada 2-24-24 Harumicho, Fuchu-shi, Tokyo Toshiba System Technology Corporation

Claims (4)

[Claims] 1. A distribution line belonging to two distribution substations is extended while each of the distribution lines is divided into a plurality of sections by a plurality of normally closed switches, and each distribution line is normally opened at an interconnection point at a terminal. In a distribution line having a configuration in which a loop is interconnected via a switch, a loop availability determination unit that selects a loop distribution line for an input power failure target section, and a normally open switch corresponding to a case where the determination result is impossible. An automatic distribution line loop switching device, comprising: a phase operation means for transferring a corresponding power failure section adjacent to a power distribution line to a phase leading side distribution line. 2. A distribution line belonging to two distribution substations is extended while dividing the distribution line into a plurality of sections by a plurality of normally closed switches, and each distribution line is normally opened at a connection point at a terminal. In a distribution line having a configuration that is loop-connected via a switch, a part of a load belonging to one distribution substation is shifted to the other distribution substation by operating a connection point switch, An automatic distribution line loop switching method, characterized in that a phase angle on both sides of the interconnection point is reduced to prevent occurrence of an overcurrent of a distribution line breaker that occurs at the time of loop switching. 3. The automatic distribution line loop according to claim 2, wherein a load between banks is shifted via a secondary bus of the bank in order to reduce a phase angle on both sides of the interconnection point. Switching method. 4. The automatic distribution line system according to claim 2, wherein the secondary voltage of the bank is changed through a tap switching operation of the bank in order to reduce the phase angle on both sides of the interconnection point. Loop switching method.